ABSTRACT. The HCM City locates at the soft soil and the low elevation of the land, rivers and canals form a complex network that is affected by tide. This paper discusses the relation between land subsidence and sea level-rise that impacts of the flood on low-lying land due to the combined effect of tide and land subsidence. Groundwater exploitation is a major cause of land subsidence has resulted in tides moving into low-lying areas that were previously above high-tide levels. Evaluating the subsidence rates (annual average, 1997 – 2018) by analysis of Permanent Scatterer InSAR (PSInSAR) Technique showed that over 140km2 of the area has suffered the land subsidence (0, 67% area of HCM city) with the maximum rate of subsidence is 10 - 15 mm/year. In addition, HCM city dominantly consists of plains of which the percentages are 60 % is that ground elevation level is below +1.5m while current max tide level: +1.68 m. The effect of land subsidence and sea level rise caused residents in many wards suffered water-logging of between 0.4 - 0.5m. Each year, climate change could cause sea levels to rise by 3mm and land subsidence makes this situation even worse. These results provide an important step towards flood prevention plan that aims to achieve the sustainable urban development.

ABSTRACT. Antibodies are indisputably the most successful reagents in molecular-targeting therapy. However, use of antibodies has been limited due to the biophysical properties and the cost to manufacture. To enable new applications where antibodies show some limitations, we have developed an alternative-binding molecule with non-immunoglobulin domain. The molecule is a helix-loop-helix (HLH) peptide, which is stable against enzyme degradations in vivo and is too small to show immunogenicity. Here, we introduce our HLH molecular-targeting peptides, termed “microAntibodes”, that show antibody-like functions, high affinity and high specificity for the targeted proteins.

Since the HLH peptide folds by virtue of hydrophobic and electrostatic interactions between the amino acid residues positioned inside the molecule, the outside solvent-exposed residues are possible to be mutated with a variety of amino acids to give a combinatorial library of the HLH peptides. Based on our technology of phage-displayed libraries for catalytic antibodies, we constructed a phage-displayed library of the HLH peptides. The library was screened against G-CSF receptor to give a binding peptide, which was cyclized by a thioether linkage between the N- and C-termini. The cyclic peptide showed a strong binding affinity (Kd of 4 nM) to the receptor and a long half-life (>2 weeks) in mouse sera, proving an enzyme-resistant property. Immunization of the HLH peptide to mice showed no induction of the antibody production (non-immunogenic). We have applied our HLH peptide libraries for VEGF, IgG/Fc, interleukins (IL-5, IL-6), and kinases (Aurora A) to obtain their molecular-targeting peptides “microAntibodies”. In addition, we used the HLH peptide as a scaffold for generating cell permeable molecular-targeting peptides through bi-functional grafting: epitope grafting to provide binding activity and arginine grafting to endow cell-permeability. In this symposium, recent advances of our studies on molecular-targeting HLH peptides will be introduced and discussed in detail

ABSTRACT. The amount of shrimp and crab waste from shellfish processing has undergone a dramatic increase recently. In addition to edible parts, the amount of chitin-containing waste can be as high as 60-80% of the biomass. Squid processing also generates a large amount of byproducts. These represent 35% of the total mass caught and include the head, viscera, skin and bones. To offset environmental pollution and disposal problems, marine byproducts are used to produce silage, meal and sauce. They are also used in the production of value added products, such as proteins, hydrolysates, bioactive peptides, collagen, gelatin and chitin. Research on the production of fish protein hydrolysates currently focuses on maximizing the industrial potential of the waste material. Chitin has received the most attention and by extension, shrimp, crab and squid processing. Numerous studies have demonstrated that byproducts from fish, shellfish and squid processing are suitable for human consumption, animal food and other applications with high market value. Indeed, these marine byproducts are a source of interest for their collagen, peptide, polyunsaturated fatty acid and chitin content. This paper provides an overview of the extraordinary potential of fish processing byproducts and their applications.

ABSTRACT. In this study, we aimed to prepare and modify various types of titanate nanotubes (TNTs) and apply them for removal of indoor formaldehyde by photocatalysis. The TNTs materials were synthesized by hydrothermal method and then modified by treatment at different acidic - basic conditions (pH 1 – 9) and annealing at different temperatures (100 – 900 oC). The effect of environmental factors such as inlet concentration, exposed surface area, residential time, light intensity, and catalyst amount was also investigated. Results showed that the materials treated at pH 1.6 and calcined at 400 oC had the highest formaldehyde removal efficiency, which could be due to the suitable condition of anatase crystallinity and surface area. For reaction condition, the highest removal efficiency of 99% was found at condition of 2 UV light bulbs, 29 second for retention time, 0.11 g of TNTs, 15 ppm of HCHO, and 3 glass substrates. These parameters could be very useful for further design of a photocatalytic device which can be applied for removal of air pollutants in indoor air.

ABSTRACT. Imidacloprid is the main content in many popular pesticide in Vietnam. These products were imported and manufactured to supply for agriculture needs. Wastewater generated from these factories contains high amount of Imidacloprid, which is difficult to remove traditional methods. In this study, Electro Fenton process is used to decompose Imidacloprid in wastewater. Fe3O4/Mn3O4 is used as a catalyst for its good characteristics: strong catalytic potential, easily separated and reused by magnet. A synthetic wastewater source with 237 mg/l Imidacloprid was synthesized. pH, catalyst dosage, current density were investigated to find suitable treatment conditions. The results showed that, at pH of 7.3, current density of 20.8 mA/cm2, and catalyst dosage of 0.45 g/l, the removal of TOC were 98.3%, corresponded to a TOC content of 0.48 mg/l. In addition, Imidacloprid was not detected in the effluent. Besides, the mechanism of Imidacloprid decomposition by Electro Fenton process with Fe3O4/Mn3O4 catalyst is also recommended.

ABSTRACT. Groundwater is one of the main water supply sources for domestic purposes in rural areas of Vietnam. However, Arsenic contamination of groundwater in many has posed threats to human health, in particularly in rural areas. According to statistical data of Ministry of Health, there are approximately 21% of Vietnam’s population is consuming Arsenic contaminated water sources which exceeds permitted level. Particularly, the situation is exacerbated in the Red River Delta and the Mekong Delta. The purpose of this paper is to present the efficiency of Arsenic removal by using magnetic nano material – cobalt ferrous oxide (CoFe2O4) with performance of optimization of pH, dose usage and time. Scanning electronic microscopy (SEM) and Fourrier Transformation Infrared (FTIR) were deployed to identify nanoparticle and peaks. The results of SEM showed that the nanoparticle is 70 – 95 nm, and the measurement of FTIR showed typical peaks of magnetic nano at 568 cm-1 and 412 cm-1 as well as typical peaks found at 1134 cm-1 and 983 cm-1 found are corresponding to bonds of C-O, C-O-H groups, which are able to adsorb heavy metals in water environment. The results also showed that at the pH 6.5 with 50 mg of CoFe2O4 in 40 minutes, arsenic (removal) treatment efficiency is 90.55%. Further, this nanoparticle is highly applicable due to it can be recovered and reused.

ABSTRACT. In this study, commercial reactive dyes were effectively removed from water samples through adsorption on eggshell powder-chitosan gel (EPCG) material at 30 oC. The EPCG material was synthesized from waste eggshell with industrial chitosan in order to form a novel core-shell material in which chitosan was coated as a thin layer on the surface of eggshell. SEM and FTIR results showed that the porous structure of dried EPCG is very potential for adsorption application. In dyes adsorption tests, Langmuir and Freundlich equations well described the adsorption isotherms with maximum capacity of 2.3 mg/g at pH 4 and equilibrium time of 60 min (r2 > 0.98). Additionally, the adsorption process followed pseudo-second-order kinetic. Adsorption behavior as well as the breakthrough curves of reactive dyes in fixed-bed adsorber was also evaluated, where the adsorption was better described by the Clark model (r2 > 0.92) than by the Bohart – Adam model (r2 > 0.82). These results suggest that EPCG, as an environmental-friendly material produced from waste eggshell, is very promising for wastewater treatment applications.

ABSTRACT. Wastewater of natural rubber industry contains high pollution content. Drainage of rubber industry consists of latex, organic matter and nitrogen containing compounds. Concentrations of contaminants are 1.500 ÷ 7.000 mg/L (COD), 3.500 ÷ 14.000 mg/L (BOD), 200 ÷700 mg/L (SS), 200 ÷1.800 mg/L (TN), 500 ÷ 2.000 (Sulphate). The wastewater is studied for reuse in agricultural irrigation due to high nitrogen concentration. Pollution reduction of irrigation water when irrigating plants is carried out in a laboratory scale. Experimental models are constructed of soil from rubber field. The research results show that after irrigation, the concentration of pollutants is lower than the permitted level of National Technical Regulation of Vietnam. Membrane filtration technology is also applied to rubber waste after secondary treatment. Material of membrane is needed to be considered on cost-effective, membrane fouling and membrane cleaning. Both microfiltration and ultrafiltration can be used for wastewater treatment but depending on particle size of solutions. Microfiltration membrane has pore size ranging from 0.1 to 10 m and UF ranging from 0.1 to 0.01 m. Experimental results with PAN, PVDF membrane showed that the ability to remove pollutants remaining in secondary treatment wastewater is over 98%. The results of this study are the basis for managers to choose the appropriate solution for the rubber latex processing industry.

ABSTRACT. Anaerobic process is one of the alternative methods commonly applied for the treatment of leachate stream generated from solid waste landfill. However, this method becomes less effective to degrade contaminants containing lower biodegradability organics with higher salinity and nutrient constituents, particularly in the later stage of landfill operation. Thus, further treatment is required to efficiently meet the effluent standard. Among the physicochemical methods, electrochemical oxidation using boron-doped diamond can be applied as a post-treatment due to its effectiveness. This anode may promote the generation of active species, such as radical anions (OH•, Cl•, Cl2•-, and SO4•-) as well as other oxidative agents, creating more indirect oxidation processes of non-biodegradable organic contaminants. Therefore, the aim of this study was to evaluate the efficiency of electrochemical oxidation using boron-doped diamond for the treatment of anaerobically treated leachate effluent. The impact of sulfate ion addition on the overall performance of the electrochemical oxidation was also investigated. This study was conducted using a laboratory scale of the three-compartment electrochemical reactor, consisting of anode, cathode, and central compartments. A 2-L of pre-treated leachate was recirculated in a batch electrochemical system by applying constant current density of 25; 37.5; and 50 mA cm-2. The optimum condition for organic (measured as chemical oxygen demand, COD) and total nitrogen removals, i.e., 92% and 59%, respectively, was achieved at a current density of 25 mA cm-2, with the molar ratio of [SO42-]:[Cl-] = 0.25:1. This equals to the removal of 2.28 g of COD and 1.77 g of total nitrogen, thus the total energy required was 5.7 Wh g-1 COD and 7.5 Wh g-1 N, respectively. Furthermore, the result confirms that the addition of sulfate ion seems to benefit the removal of COD through indirect oxidation and lead to the formation of nitrate without overall removal of total nitrogen.

ABSTRACT. Mature solid waste landfill produce stabilized leachate with extremely low biodegradability. It renders the leachate untreatable biologically. Therefore, a pretreatment aimed to increase leachate biodegradability deems necessary prior to biological treatment. The objective of this study is to investigate the effectiveness of electrochemical oxidation process in enhancing leachate's index of biodegradability, expressed as BOD5/COD ratio. Different types of anodes were employed, namely DSA (dimensionally stable anodes) and BDD (boron-doped diamond), to represent active and non-active anode, respectively. A 2, 1.5, and 1 L leachate samples were treated in a batch recirculation reactor using a 200 mL single compartment electrochemical cell where the initial pH was set to 3, and flow rate to 5 mL s-1. The reactor was operated under constant current, with a current density of 10, 30, and 50 mA cm-2. Both DSA and BDD anode were capable of reaching targeted BOD5/COD ratio above 0.5, as an indication of biological treatability of pretreated leachate. Under the current density of 30 mA cm-2, the highest BOD5/COD ratio of 0.576 and 0.599 was obtained using BDD and DSA, respectively, at which operation condition the COD removal was 72% and 67%, respectively, after 4-h electrochemical oxidation.

ABSTRACT. Using joss paper is a traditional and long-term historical custom in Vietnam. In those countries having this custom such as China, Taiwan, there were many studies conducted on measuring air polluted particles, particulate matters releasing during burring process of joss paper in worship activities. The joss papers sample has shown the existing of heavy metallic elements to be in the order of Al>Fe>Mn>Cu>Pb>Zn>Cd. Those metal contents will be release to the environment by ash. The metal contents in ash samples showed that Cu content is higher according to the standard of QCVN 03:2008/BTNMT for land with 70ppm. Gold ingot paper ash –T1: 236.21 ppm; gold paper ash –T2: 78 ppm; printing paper ash –T3: 415.87ppm. In particular, ash from burning gold ingot paper (T1) had the highest heavy metal contents: Cd (4.93 ppm) comparing to the threshold of the standard is 5ppm; Pb 128.60 ppm higher than the standard (120 ppm). This result will help to assess the risk of T1 to the soil. These experiments showed that heavy metal in the mixture between ash and soil affected on germination rate.

ABSTRACT. Ho Chi Minh City’s rapid population growth rate in Vietnam, that is make a great challenge in power demand. The main sources of electricity supply are from hydropower plant and thermal power plant, but it has overcome the ability supply. That’s why renewable energy is considering as the potential source for electricity supply in future. As one of the metro-city in Vietnam, with 8,224,000 people in Ho Chi Minh City and terrain conditions, the solar energy has been evaluated as a potential renewable energy for electricity supply [1]. The implement of large scale solar energy in enterprise/company is widely with high capacity because it can reduce the electricity price and product price. Besides, the small scale of solar energy has been starting using for households in Ho Chi Minh. And Phu Nhuan district is one of 24 districts belong to Ho Chi Minh City with crowded residential, that also has 1-2 houses applying solar energy. So, this research was investigated the potential using solar energy for household and viewpoint of resident about applying solar energy for their home. According this study, now there is 1 house using and rating positively about solar energy combine national power grid. Around 50% people (1,012/1,500 votes) think that using solar energy is potential applying in their home because it gains the economic efficiency for reducing electricity fee. According the survey in 15 wards of Phu Nhuan district were showed it’s over 60% people agree to apply the solar energy. In addition, the national government released the policy to support the financial for apply solar energy in household, that is strongly encourage the resident changing their thinking and start considering to apply solar energy at their house.

ABSTRACT. Crude oil exploration is high risk activity that require skilful manpower and advance technology. Current exploration in Indonesia not only focus on onshore facility but also offshore facility since oil reservoir is much larger in the ocean subsurface. Global warming potential (GWP) is determined by how much carbon dioxide (CO2) is generated. Usually, carbon dioxide is monitored manually using sensor in the stack or flare. However this method has no advantage to cover carbon dioxide generation from entire activity in the platform and limited to the substance in the certain place. In this research, we studied global warming potential generated by offshore platform facility using life cycle analysis model. We gather representative variables that used for generating life cycle analysis model and analysed using ReCiPe method on midpoint level. Result show that GWP has also generated from different activity other than flare and stack. In addition, this result also show that GWP based on life cycle analysis may be a good addition for monitoring report since it provide specific environmental impact data based on activity while manual monitoring cover real time emission measurement.

ABSTRACT. Digital data (images and DNA sequences) of aquatic macroinvertebrates inhabiting Japan are preliminarily released on the internet web site (http://www.b.s.osakafu-u.ac.jp/~mkato/J-amir_home.htm) along with the sampling information. Physical collections (specimens) are stored at the laboratory of Riverine Metagenomics Research Group (RMRG lab.) of Osaka Prefecture University, from which genomic DNA was isolated and the specific DNA sequences (partial coding regions of 18S rRNA, histone H3, and mitochondrial cytochrome c oxidase subunit I genes) were determined. Ones who are interested in the contents of J-amir, can access the physical specimens for inspection, can get full resolution digital images upon request to the RMRG laboratory, and can retrieve DNA information from International DNA Databases (GenBank/DDBJ/ENA). DNA information associated with properly identified specimens in the databases is mandatory for the metabarcoding studies and environmental DNA (eDNA) analyses. Also, high resolution digital images of well characterized specimens are useful for taxonomy education. As of the end of February 2019, our collections include 76 species of Ephemeroptera out of 152 species, 52 species of Trichoptera out of 483 species, 23 species of Odonata out of 211 species, 15 species of Plecoptera out of 202 species that are identified to inhabit Japan, respectively, and a few taxa in the other groups. We are currently working to expand the collections of specimens including planktons and fishes to establish the Japanese aquatic living organism references on the internet web (J-alor).

ABSTRACT. Cohesive mud flocs in coastal waterways can go through repeated cycles of deposition and erosion before being sequestered in a final deposit. Unlike sand and gravel, mud flocs have the potential to change size and density during their time on the bed. Such changes could influence the rate of resuspension or the size characteristics of resuspended flocs relative to those that do not spend time on the bed. Here we use laboratory experiments to quantify the influence of sediment and water-column properties on resuspension characteristics of mud flocs. Specifically, we examine how concentration at the time of deposition, the length of time for which the deposited material is on the bed, and the turbulence levels in the water column while the flocs are on the bed all impact the nature of the flocs on the bed and their resuspension characteristics. The resuspension characteristics we quantify are: (1) the difference between the floc size population before and after resuspension, (2) the rate of resuspension, and (3) the difference between the concentration at the time of deposition and at full resuspension. The experiments show that flocs grow in size while on the bed, but that resuspended flocs quickly revert to size populations that are in equilibrium with the local water column conditions. The results also show that under low turbulence levels, flocs moving around on the bed increase in size, and such flocs can be more difficult to resuspend. Furthermore, the time that the flocs are on the bed has little impact on the resuspension rates unless sediment concentration in the water column at the time of deposition is above a critical value for the onset of a space and load-bearing network. For concentrations above this critical value, freshly deposited mud begins to consolidate and become more resistant to erosion with time.

ABSTRACT. This study aims to understand how the residents prioritize the benefits of urban sustainable drainage techniques and identify the predictors for their prioritization. We conducted a face-to-face survey with a sample of 228 residents in Nhieu Loc - Thi Nghe sub-basin, one of the main drainage catchments in Ho Chi Minh City. After importing data to SPSS software, we used the Wilcoxon signed-rank test to examine the statistically significant difference in pairwise groups of benefits. As the results, while the respondents set the least priority to amenity creation, they expressed the same preference for flooding control and environmental enhancement. The independent variables in logistic regression models are divided into two groups: personal information and location characteristics (neighborhood environment). The findings from this study will be the significant input of multi-criteria decision-making in retrofitting sustainable urban drainage system in Nhieu Loc - Thi Nghe sub-basin.

ABSTRACT. Water resources management plays an important role in the socio-economic development of arid or semi-arid provinces like Ninh Thuan. Recently, the amount of surface water in dry seasons in this province is being depleted increasingly due to the negative impacts of climate change and human activities. This not only affects the productivity of agricultural and industrial sectors, but also causes the water shortage for domestic use in the province. Therefore, the use of hydrological models in stream flow simulation and prediction in arid or semi-arid regions is considered one of the most effective measures to support and improve the integrated water resources management. In this study, a conceptual rainfall-runoff model (namely GR4J) was used to simulate and forecast the stream flow in the Cai-Phan Rang river basin, Ninh Thuan province. This model has been successfully applied in several semi-arid regions in the world, where have few hydrological stations or poor recorded data. The performance of GR4J model was assessed at two middle gauges in the Cai –Phan Rang river basin using the Nash–Sutcliffe model efficiency coefficient (NSE). The optimal model parameters obtained were then used to simulate and predict the flow at the outlet of the basin. The model results demonstrate that the GR4J model has a good performance in simulating the flow in the Cai - Phan Rang river basin with the NSE of over 0.8 for the middle gauges. The predicted flows also indicate realistic and plausible values and are expected to support the decision makers in water resources management in Ninh Thuan province.

ABSTRACT. Forecasting hydrological factors, particularly reservoir water level, plays an important role in reservoir operation and management. To meet this requirement, many studies have been carried out using the traditional methods (such as conventional auto-regression, autoregressive moving average, and multi-linear regression) and recently artificial intelligence methods (such as Artificial Neural Network (ANN)). Compared to the traditional methods, ANN has the advantage of solving the complex non-linear problems with the number of input parameters and/or limited data. In this study, an ANN model was developed in Microsoft Excel to forecast the 10-day ahead water level at Dau Tieng reservoir in Vietnam. This ANN model used the Back-Propagation algorithm, which can transmit the output error signals backward from the output node to the input nodes in order to adjust model parameters. An optimization algorithm was also applied to minimize the total error between the model and measured values. The computational experiments with different model parameters were set up to determine the most favorable model structure. The input data used include the water level, inflow, outflow, and rainfall in the reservoir basin in the period of 2001 – 2006. The results proved that the developed model can be used to forecast for Dau Tieng reservoir, as the coefficient of determination, R2 is in the range of 0.97 to 0.99. The forecasting results are also expected to support the operational activities of the reservoir.

ABSTRACT. Anaerobic osmotic membrane bioreactor has been recently attracted more attention due to its high water quality and biogas product. However, the most challenge in traditional AnOsMBR system is membrane fouling in long term operation. For the first time, an innovative concept of combining sponge-based moving bed (SMB) and a submerged anaerobic osmotic membrane bioreactor (OsMBR), known as the SMB-AnOsMBR hybrid system, were investigated using 0.2 M MgCl2 coupled with 0.2 M Na3PO4 salt as the draw solution to treat the wastewater. In this study, continuous moving sponge around the bioreactor based on magnetic stirred could help reduce fouling on the FO membrane surface leading to maintained water flux. Morever, AnOMBR integrated with periodic microfiltration (MF) extraction can simultaneously reduce the salt concentration and at the same time in the AnOMBR and recover the phosphorus in the precipitated struvite. The SMB-AnOsMBR/MD results showed that an average water flux of 3 L/(m2 h) were achieved in a 50-day operation and the removal efficiency of organic and nutrient compounds was higher 99%. At optimum condition of pH 9.5, the recovered precipitate contained 20% (wt/wt) of phosphorus. The overall performance results demonstrated that SMB-AnOsMBR/MD hybrid system could simultaneously recover phosphorus and water for reuse.

ABSTRACT. Phosphate and ammonium currently recovery from wastewater to produce magnesium ammonium phosphate (MAP). Several previous studies have founded precursor ions has an impact on MAP formation, such as the presence of calcium, sulfate, fluoride, and other ions. In the petrochemical company that also produces fertilizer, the wastewater contains a high concentration of ammonium, phosphate, and silica. This study aims to determine the effect presence of silica on MAP precipitation. This research was conducted in a batch system using a jar test at an optimum speed of 158 rpm for 60 minutes. MgCl2 used as a precipitation agent. This study was carried out by using synthetic wastewater. The molar ratio for synthetic wastewater of [Mg2+]:[NH4+]:[PO43-] and [Si2+] was predicted using the PHREEQC model. The pH variations of the sample were 8; 8.5 and 9. The silica concentration was varied in the range of 20 mg/L to 1000 mg/L. The parameters measured were pH, silica, phosphate, ammonium, and magnesium concentration, and MAP morphology. Silica has an impact on MAP precipitation with increasing the concentration of silica in wastewater. Recovery of phosphate and ammonium reduced respectively until 20% and 10% with the concentration of silica was 1000 mg/L under pH 9+0.2. pH has a great impact on pH 9 because the solubility of silica was increased in this pH condition. The morphology of MAP by SEM also showed that silica has an impact on the purity of the MAP.

ABSTRACT. Anaerobic digestion (AD) is a suitable technology for the conversion of lignocellulosic biomass into methane that can be used for heating and electricity generation. However, lignin is a major barrier to the bioconversion of lignocellulosic materials, which also resists the hydrolysis of lignocellulose, thus limiting its AD process. In recent years, nanobubble technology has been paid much attention in environmental field. Nanobubbles have some unique properties such as stable existence in water for a long time and generation of highly reactive free radicals that can be applied for fermentation to achieve enhanced organic degradation. Therefore, this study aimed to investigate the effect of nanobubble water (NBW) on lignin removal and its methane production during AD. The addition of nanobubble water showed a positive effect on methane production of lignin. The increase in methane production followed a descending order as N2-NBW (22% increase) > CO2-NBW (17% increase) > the control. Besides that, high methane yield was obtained in the co-digestion of lignin with acetic acid (837 mL CH4/gTOCremoval in the control reactor and 1061 mL CH4/gTOCremoval in NBW addition reactor), while methane production from mono-digestion of lignin was only 23 ml CH4/gTOCremoval in the control reactor and 40 ml CH4/gTOCremoval in NBW addition reactor, respectively. This result indicated that methane production from co-digestion of acetic acid with lignin were much higher than the mono-digestion of lignin. The ultimate methane potential with NBW addition was examined in the reactors with four different acetic acid to lignin ratios. Methane production was determined as 1054, 1028, 1061, 824 mL/gTOCremoval for ratios of 97.5:2.5, 95:5, 90:10, 80:20 correspondingly, while the highest lignin reduction was achieved in the ratio of 95:5 with 43% lignin reduction. This result indicated that the ratio of 95:5 (acetic acid:lignin) was the most favorable for lignin reduction and methane enhancement.

ABSTRACT. The expression of genes is encoded at multiple levels of complexity. Transcription, for example, initiates the reading and encoding of genetic information from DNA molecules. This process very often is regulated by a variety of transcription factors, which are a type of proteins that can enhance or suppress the translation of other genes into protein. Microscopically, transcription is carried out via protein-DNA interaction at the molecular level. However, the underlying molecular mechanism is still not clear. Using a nucleoid-associated protein Fis in E-coli as an example, we specifically look into the process of Fis dissociating from DNA. While being primarily non-specific in binding DNA, the dissociation kinetics of Fis is largely influenced by its surroundings. More concretely, the dissociation rate increases as the concentration of Fis in solution-phase increases, as evidenced by recent single-molecule experiments. This unusual behavior, called facilitated dissociation, challenges the standard thermodynamic model of gene regulation. Theoretical modeling and simulation techniques are very useful for probing possible intermediates that are difficult to explore via experimental methods alone. In this talk, I will show that the hybrid computational protocol that we develop, namely AWSEM-3SPN protein-DNA force field, allows us to explore the binding energy landscape of Fis protein with DNA so as to reveal essential dynamics of protein-DNA interaction. The simulations uncover several different pathways for the dissociation of the protein from DNA. These dissociation pathways involve different protein stoichiometries which correspond to different functional outcomes for the systems biology of gene regulation by Fis.

ABSTRACT. Green microorganisms including cyanobacteria and green algae are good models for many environmental and biochemical fields of research. It is because cells require a shorter life-cycle time when compared to that from plant cells. During their cultivation, they need simple medium compositions, no arable land, and sunlight as an energy source with a capacity in trapping the atmospheric carbondioxide to partially change to their biomass. Algal biomass could be predominantly utilized in many applications for example using as a starting material in bioenergy production. In the talk, hydrogen production from Tetraspora sp. CU2551 and Chlorella sp. KLSc59 would be discussed with the pathway of hydrogenase enzyme and photosynthetic-related pathway. The production optimization as well as prolongation in hydrogen production system using cell immobilization technique would also be discussed. Besides, a posibility of hydrogen production to a large scale production together with futuristic production aspects will also be discussed.

ABSTRACT. Spirodela polyrrhiza, commonly known as duckweed, is a species of small aquatic flowering plants that are commonly found in local ponds. The species was considered a potential candidate as an alternative source for ethanol production. This study aimed to investigate conditions for liquefaction using alpha-amylase as well as growth rates, reducing sugar contents and ethanol productivity of three different S. polyrrhiza strains BKK1, BKK2 and BKK3. During the growth period of 24 days, the growth rate of strains BKK1 and BKK3 were significantly higher than that of strain BKK2 as indicated by fresh and dry weight. Examination of conditions used for liquefaction showed that the best conditions yielding the highest reducing sugar content were 3 hours of digestion with α-amylase at 50oC and pH6. After liquefaction with α-amylase and saccharification with pullulanase and amyloglucosidase, the reducing sugar contents of strains BKK1, BKK2 and BKK3 were 27.68+0.59, 29.63+0.50 and 13.49+0.42 mg mL-1, respectively. However, the average ethanol content obtained from strain BKK3 (6.25+0.08 g L-1) was significantly higher than that from strain BKK1 and BKK2 after fermentation with Saccharomyces cerevisiae strain TISTR 5606. These results suggest that genotypic differences between S. polyrrhiza strains affect growth rate, reducing sugar content and ethanol production.

ABSTRACT. A truncated form of EBNA2 ORF was fused with GAL4 binding domain on a pGBDU-C(1) vector as the bait. A human lymphocyte cDNA library (“prey”) constructed on the pACT vector (Clontech) was screened. The positive clones were identified by the expression of ADE2 reporter, indicated by the growth of colony on the YNB[-Ade, –Ura, -Leu] medium plate. Efficiency of 1.65×106 and a total of 483 positive colonies were obtained. 421 from the total 483 positive colonies were recovered on losing the bait plasmid in the YNB[+5FOA, -Leu] medium. The insert of each recovered prey plasmid was sequenced and the gene containing the insert was identified by BLAST search. Thus far inserts from 97 clones were sequenced, of which 39 were found to be in-frame with GAL4 activation domain on the pACT vector. Some clones contain different fragments of the same cDNA. This may be helpful for mapping the interacting region in the prey protein, since the commonly shared region of these inserts might be the specific area responsible for the interaction with the bait. On the other hand, the presence of duplicated clones is a sign of saturation of the screening process.

ABSTRACT. Managing water demand is a question that always concerns apartment management boards, espcially reading water consumption index of water meter which faces many problems in terms of labor investment costs and time spent on manual reading is too long and not really effective. Currently the remote reading solution based on the principle of broadcasting and receiving radio waves is a trend in Ho Chi Minh City. This study aims to determine the performance of remote reading systems when applied on high-rise buildings. The objective of the study is to find out the scope of the activity or the best range of reading radio waves in high-rise buildings. Methods of empirical survey and statistical data were collected in May, 2019. The results showed that the radius of the broadcasting range is about 16 ms to 25 ms.

ABSTRACT. In this study, we developed a liquid crystal (LC) sensor system for detecting nitrite in aqueous solutions by using diazotization reaction as the detection mechanism. To construct this system, alkylanilines were doped into a nematic LC 4-cyano-4’-pentylbiphenyl (5CB) followed by casting a thin film of the LC mixture on a glass substrate. After that, the glass substrate casted with the LC film was immersed into aqueous solutions to form an LC/aqueous interface. In the absent of nitrite, the orientation of LC was planar and the LC image was bright under polarized light. In the presence of nitrite, it would react with alkylanilines to give diazonium ions with positive charge, which would align at the LC/aqueous interface and resulted in homeotropic orientation of the LC molecules in the LC film. As a result, a bright-to-dark transition of the LC image can be observed. The limit of detection (LOD) of this system for nitrite is 25 µM with high selectivity, and it can work in environmental water samples such as tap water, pound water and seawater. The structural effect of alkylanilines on the performance of the nitrite detection by using the LC-based sensor system was investigated. Moreover, we demonstrated that the optical signals of LC can be measured by using the build-in camera of a smartphone, which means this system is suitable for portable and on-site applications.

ABSTRACT. Squid pens powder (SPP) has been used for the production of various bioactive materials, including chitin/chitosan, exopolysaccharides, chitin/chito oligomers, enzymes, prodigiosin, anti-cancer agents, antioxidants, anti-diabetic and anti-NO compounds. In this study, SPP was effectively utilized for the production of new bioactive materials, anti-nematodes agents. SPP was used as sole carbon/nitrogen (C/N) source for the screening of active bacterial strains. Among 200 tested bacterial strains, 5 strains demonstrated potent inhibitory nematodes activity (95-100%). These active strains were further investigated their effect on nematode egg hatch and 3 of them showed effective inhibition against egg hatch (80-85%). Chitinase and protease were closely associated with the inhibition of egg hatching, while natural compounds with thermal stability play a key role in killing J2 nematodes. The optimization of fermentation condition for enhancement of activity and the identification of major constituents exist in fermented products on LC-MS analysis were also conducted in this study.

ABSTRACT. Our developed methodologies in the transition-metal-catalyzed coupling reactions1-4 involving the addition of CN multiple bonds (nitrile and imine) are briefly divided into four reaction types and shown below. As indicated in the following scheme, the different behaviors of addition could be carried out via the different transition-metal complexes. In addition, applications to the synthesis of natural alkaloids, bioactive compounds and medicine candidates could be carried out as well.

ABSTRACT. The nanocomposite was prepared by drying spray the composite of chitosan and starch with various mass ratios. Chitosan starch nanocomposite was characterized by IR, FE-SEM, zeta potential, and size distribution. Zinc and boron were loaded on the nanocomposite to make micronutrient nano-fertilizer. The size average of the nanoparticles ranged from 200 to 500 nm, the zeta potential of the nanoparticles was from 15-30 mV, depending on the ratio between chitosan and starch. The adsorption capacity of zinc and boron on the nanocomposite was of 75 to 84%, respectively. The nano-fertilizers were applied for coffee in the field. Impact of the micronutrient nano-fertilizer on the nutrient uptake of the coffee leaves was detected. The results showed that the nano-fertilizer enhanced the uptake both macronutrients and micronutrients in the coffee leaves. Especially, zinc and boron content in the leaves in the treated plots increased clearly compared to the control and to be adequate for coffee requirements. The coffee bean productivity was increased up to 12% compared to the control. It is concluded that using of the Zn/B nano-fertilizer is very potential to sustainable and green production of coffee.

ABSTRACT. A facile synthesis of isocyano arylboronate esters is presented. Although tri-coordinate boron functional groups are commonly recognized as vulnerable to nucleophilic attack, the newly reported tri-coordinate isocyano arylboronate esters were found to be stable, albeit owing to the presence of an isocyano group. Theoretical calculations, using the DFT/B3LYP/6-31G(d,p) method, revealed that the electron delocalization between the aryl group and the boron atom might contribute to this stability. UV-vis spectroscopic investigations on 2-(4-isocanophenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane were in agreement with the theoretical studies, showing a red-shifted absorption compared with that of phenylisonitrile. The reported strategy allows boronate ester substrates to survive throughout multiple steps operations. These building blocks were exploited in two isocyanide-based multicomponent reactions and tetrazole formation reactions.

ABSTRACT. Boron neutron capture therapy (BNCT) is a potential approach to treat cancer and Sodium borocaptate (BSH) has been used for BNCT application as a boron delivery agent. Even though, BSH were used in clinical trials, this agent till exhibits some disadvantage in the case of selective targeting of cancer cells and cellular uptake ability. Folic acid and biotin were considered as an excellent targeting ligand which can help to overcome the disadvantage of BSH in BNCT application. In this study, we prepared the natural sodium borocaptate (BSH) from natural abounded starting materials and we also successfully conjugated this potential BNCT agent with folic acid/biotin using 1-(2-Aminoethyl)maleimide as the short crosslinker. Folic acid/biotin-conjugated BSH exhibited the potential boron delivery agent which decreased the cytotoxicity of BSH treatment effects on the Human Bone Osteosarcoma Epithelial Cells, the U2OS cell line. Interestingly, folate-conjugated products which showed two maleimide groups and it also exhibited the high fluorescence emission. Of these, this complex might provide a new strategy to enhance and also detect the boron accumulation. These observations offered two of new BSH delivery platforms which were described as a small molecule weight and highly targeting of cancer cells and could potentially be used in further investigation.

ABSTRACT. Climate Change (CC) is a global concern as the weather changes, that is going on under the negative trend. Temperature, rainfall, sea levels, and extreme weather events are increasing bulk entail consequences to the environment and humans. Especially, the impact of climate change to human health are being main targeted researching in nowadays. Following to the Asian Development Bank (ADB) report in 2010 [1], Ho Chi Minh City is one of the top 10 cities in the world, that is the most vulnerable by the climate change. And Nha Be district is belong to suburban of city. Through mechanical survey data of Ho Chi Minh City Statistical Office in 2017, the average population in Nha Be is 177,990 people [2]. With geolocation riverine terrain of canals plus population is increasing mainly immigrants led to pressure on infrastructure, the disease situation stems from water sources is also likely to occur, especially affecting the quality of the environment and people’s health district. So, this research has been survey and evaluated the connection between bad weather in raining season and human’s health about Hemorrhagic Fever’s disease (DHF) in Nha Be district in 2018. By this investigated had been shown the diseases related to the respiratory tract such as bronchitis is at risk of frequent (64%), DHF is only 28%, respectively. And the report of Nha Be District Health Center had also show there are 1,987 cases of bronchitis is higher than other diseases (in 2017) by climate change [2]. But dengue is easy to outbreaks of disease and difficult to control, that’s why Preventive Medicine Center of Ho Chi Minh City is more concern and control about DHF, especially in Nha Be district.

ABSTRACT. Street trees play a very important role in reducing pollution and protecting the environment. The management of urban trees is a practical need, so it is necessary to manage urban trees resources including street trees effectively in the context of building a clean, green city and sustainable development. However, the monitoring and management of green trees still face many difficulties. The geographic information system (GIS) with the advantage of multi-layer spatial analysis will provide technical assistance in the management and protection of street trees, creating more favorable conditions than traditional methods as statistical reports, forms.... The number of trees of September 2018 of District 11 is 1842, less 31 trees compared to 2011, in which the floating rooted trees account for the largest number 38 trees, 20 trees is decay rooted ... and many the road has almost no trees. For that reason, this paper build a database to serve greenery management for the study area and propose solutions to manage trees effectively.

ABSTRACT. According to the United States Environmental Protection Agency (US EPA), slaughter wastewater (SWWs) are classified as one of the most detrimental industrial wastewaters to the environment. The organic and nutrient concentration in this wastewater is very high and the residues are moderately solubilized leading to polluting effect for environment and health of people. The objective of this study was to investigate the effective removal of ammonium in slaughter wastewater by Upflow anaerobic sludge blanket (UASB) technology combined with expanded granular sludge bed (EGSB) using anammox and PVA Gel. The system was operated in 2 phase. Average ammonium loading rates (NLRs) was increased from 0.25 kg N-NH4+m−3d−1 to 0.75 kg N-NH4+m−3d−1 with hydraulic retention times (HRTs) was 12, 6 and 4 h. In phase 1, The combination of UASB technology and EGSB using anammox for removal of ammonium was investigated, ammonium removal efficiencies were about 37 % (NLRs = 0.25 kg N-NH4+m−3d−1), 64% (NLRs = 0.5 kg N-NH4+m−3d−1) and 55% (NLRs = 0.75 kg N-NH4+m−3d−1), Nitrite removal efficiencies were about 52 % (NLRs = 0.25 kg N-NH4+m−3d−1), 76% (NLRs = 0.5 kg N-NH4+m−3d−1) and 64% (NLRs = 0.75 kg N-NH4+m−3d−1). In phase 2, PVA Gel was supplied in EGSB as biomass carrier for growing anammox sludge. The result showed that ammonium removal efficiencies were about 56 % (NLRs = 0.25 kg N-NH4+m−3d−1), 68 % (NLRs = 0.5 kg N-NH4+m−3d−1) and 60% (NLRs = 0.75 kg N-NH4+m−3d−1), Nitrite removal efficiencies were about 55% (NLRs = 0.25 kg N-NH4+m−3d−1), 77% (NLRs = 0.5 kg N-NH4+m−3d−1) and 73% (NLRs = 0.75 kg N-NH4+m−3d−1). After the research process, anammox bacteria has grown on the surface of PVA Gel.

ABSTRACT. Chitinous fishery byproducts are attracted sources to produce various potential bio-activity compounds. In this study, different kinds of marine chitinous materials (squid pens, demineralized shrimp shells, shrimp heads, and demineralized crab shells) were used to provide the C/N source for chitosanase production by Paenibacillus sp., a chitinolytic bacterial strain isolated from Taiwanese soil. The chitosanase was purified by a series of steps, including ammonium sulfate concentration, High S chromatography and HPLC using KW802.5 column. The molecular weight of the chitosanase was estimated by SDS-PAGE method. Other characters of the enzyme were also investigated, resulting in interesting properties such as thermal stability and high optimal temperature point. Chitosanase from Paenibacillus sp. was applied to prepare different chito-oligosaccharides fractions, which showed the anti-α-glucosidase and anti-oxidant activities. In short, the chito-oligosaccharides fractions obtained by hydrolyzing chitosan Paenibacillus sp. chitosanase may have potential use in medicine, agriculture, and nutraceuticals.

ABSTRACT. Forward osmosis (FO) technology is an alternative process for dewatered solid–liquid stream which has the potential to be innovative and sustainable. However, the applications have still been hindered by high reverse salt flux and membrane fouling. In this study, a hybrid forward osmosis–nanofiltration (FO/NF) process was designed for dewatering high nutrient containing sludge and recovering draw solution with minimum energy using EDTA-2Na coupled with Triton X114 as novel draw solution. Results showed that 0.06 M EDTA-2Na combined with 0.8 mM Triton X114 achieved the lower reverse salt flux than that of 0.06 M EDTA-2Na as draw solution in FO process. The after 20 h of FO operation, final sludge concentration reached 35,000 mg/L. Moreover, nutrient compounds in sludge were successfully removed by the FO membrane with a removal efficiency of approximately 95% of NH4+ –N and 99% of PO43- –P, which was attributed to the multi-barrier layers of sludge forming on membrane surface and the steric effect of the FO membrane. Furthermore, NF-TS80 membrane was used to recovery draw solution could reach more efficiency with approximately 95%.

ABSTRACT. Xylan-containing agricultural byproducts possess significant application in many fields. In this study, six sources of carbon, including rice bran, wheat bran, spent coffee ground, coffee husk, xylan from birchwood and carboxymethyl cellulose, were investigated for xylanase production by Streptomyces thermocarboxydus TKU045, a xylanolytic actinomyces isolated from Taiwanese soils. S. thermocarboxydus TKU045 expressed the highest xylanase productivity (0.803 U/mL) when cultured on a medium containing 1% of wheat bran as substrate and 1% of nitrogen source (KNO3) on 3 days at 37 °C. The molecular weight of S. thermocarboxydus TKU045 was determined at approximately 15 kDa by Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis. The characterized xylanase expressed some interesting properties, such as a various pH stability (pH 4-9) and a higher temperature optimum (60 oC). TKU045 xylanase was purified 81.7-fold with an activity yield of 1.0 % and a specific activity of 5.056 U/mg. Thus, S. thermocarboxydus TKU045 may have potential in xylanase production and the solve environment problems.

ABSTRACT. At present, Thailand has about 27,185 petrol stations. The effluent from the station has a high COD value. Wastewater is released into the water sources without treatment. It greatly affects the environment. The objective of this research was to study the treatment of synthetic wastewater from lubricant with the COD concentration of approximately 10,000 mg/L. and pH value of about 5-6. Determining the optimum conditions for the treatment by persulfate/ferrous ion and the treatment by sulfate/ferrous ion together with the sonication process were performed. The study factors were as follows: the amount of ferrous ion 0.00 -0.05 mole, the molar ratio of ferrous ions per persulfate 1: 0 - 1: 5, pH 2-6, reaction time 0-60 minutes and sonication time 0-40 minutes. Distilled water was tested to be a blank. Every experiment was repeated three times to find the mean and standard deviation. The results indicated that the amount of ferrous ion 0.04 mol, the molar ratio of ferrous ions: persulfate 1: 1, pH 3 and reaction time of 40 minutes could reduce COD more than 94%. Furthermore, the results showed that COD value was reduced by more than 94 percent when using sonication time for 30 minutes. However, synthetic wastewater from this research still could not be released into water sources because it exceeded the effluent standard (200 mg/L) prescribed by the Department of Industrial Works. Co-treatment of the wastewater with other methods is necessary to meet the effluent standards.

ABSTRACT. Vegetation cover (VC) plays an important role in regulating the water, decreasing the drought and soil erosion... VC variation can break the ecological balance, affect the animals and human activities. Google Earth Engine (GEE) has been proved as a powerful tool by providing accessing right, analyzing images and data on integrated system. Furthermore, it possesses the ability to perform spatial aggregations over global-scale data at a high computational speed, supports both spatial and temporal analysis. This paper presents application of remote sensing method, based on GEE platform to monitoring and evaluate VC change on Ly Son island, in Quang Ngai province from 1990 to 2018. The results show that VC has close relationship with environmental factors, and severely influenced by human activities on a large scale. Environmental factors like temperature and rainfall have close relationship with VC. This is shown in increasing NDVI during rainy season and it repeats year by year in research term. Human activities affect VC by large-scale and continuous construction work. The research results contribute the local government the understanding about VC change, in order to recommend solutions for better managing the island environment

ABSTRACT. Surface water contains clay, bacteria, dissolved metals, organic matter, color, other suspended solids. The purpose of coagulation and flocculation is to remove these suspended particles which ensure proper operation in treatment plant. Improper use of coagulant dosage affects water quality after treatment, cause operation problems and production costs. A study is being conducted at a surface water treatment plant at Dong Nai River with the capacity of 300,000 m3/day. The treatment process uses iron alum for coagulation and flocculation. Due to the high corrosion property of iron alum and the residue effects of the quality of treated water, it requires strict control in the treatment process as well as the chemical dosage. The main aim of this study is to determine appropriate amount of alum used for the coagulation-flocculation process. Research method is data collection including: turbidity, pH, flow rate of raw water, dosage of iron alum, lime, polymer used in current treatment process. Then, find the model using iron alum by linear regression analysis and BMA methods on R tool platform. Next, verify the appropriate linear regression model of iron alum by Jar test experiment. Results revealed that the BMA model is not suitable for the application because one Jar test results has a mean turbidity value greater than 4 NTU, which does not meet the water quality requirements after sedimentation tank according to the water treatment regulation. The linear regression analysis showed that raw water turbidity and season are two independent factors related to the alum dosage, of which these two factors explain about 78% of the differences that affect the coagulation-flocculation process. This study was successful in determining the appropriate iron alum dosage for the water treatment plant, which can be applied similarly to build appropriate chemical model for water surface water plants and raw water resources.

ABSTRACT. Organic dye sensitizers have been molecularly engineered and employed in dye-sensitized solar cells (DSSCs) where the power conversion efficiencies (PCEs) is looking forward to be better and better. In order to absorb sunlight more effectively, the structure of organic dyes usually apply a p-conjugated system with a strong electron donor moiety and a strong electron withdrawing moiety that lead to an intramolecular charge transfer (ICT) absorption band of the dyes. In this work, we synthesized a series of metal-free organic dyes by using different amine-based electron donors (D), and indolium as the electron acceptor (A). Because the strong electron withdrawing ability of indolium moiety, these D-pi-A dyes possess strong molecular dipole such that an intramolecular charge transfer band with high molar extinction coefficient was measured. The electrochemical properties of the indolium-based were measured and the molecular geometry of the dyes were investigated by using theoretical calculations. In addition, the device performance of the DSSCs applying the indolium-based dyes as sensitizers was characterized.

ABSTRACT. In past studies, conventional LC-based sensors apply metal grids on glass substrate to fill with LCs as the sensing platform to detect the analytes in aqueous or gas phases that in contact with LCs. This platform is easy to prepare, and it has been applied to detect various analytes such as proteins, proteases, small molecules and metal ions…etc. However, the LC-based sensing platforms applied metal grids have some drawbacks including the metal grids are easy to deform when handling, the positon on metal grids on the substrate may move in a flow aqueous system and metal grids may influence the arrangement of LCs. Therefore, the practical applications of LC-based sensors in current environmental and biological detection are still limited. In this study, we prepared the fine grids patterned on glass substrate by using photolithography of negative photoresist. These fine grids were filled with LCs to construct the LC-based sensors. Owing to the good mechanical strength, photostability and chemical stability of photoresist, the advantages of this approach to construct the LC-based sensors includes the grids are not easy to deform, the grids are firmly adhered to the glass substrate and the grids would not influence the arrangement of LCs. On the other hand, the signal ratio of photoresist grids is about one hundred times higher than metal grids. Based on this phenomenon, it can have a better signal discrimination rate when analyze data, and can also reduce the chance of misjudging the signal.

ABSTRACT. In this study, we focused on how to development an oil-based stable silver nanoparticle suspension of conductive ink, to enhance the attachment of ink onto the substrate, and to seek the best condition for printing quality. Furthermore, the stability mechanism and related applications were discussed in detail, such as the use of prepared dispersion solution to produce a conductive film, and further to obtain a conductive pattern. First, silver nitrate was used as the metal precursor and ascorbic acid was added as the reducing agent with the addition of the surfactant and the protective agent. Through a series of formulations to obtain the best performance, we developed the oil-based conductive silver ink, whose dispersion could maintain stable more than one year with no obvious precipitates. The ink was coated onto a glass slide via drop-casting method, and a conductive film was obtained by sintering at 250 oC having a sheet resistance of lower than 0.6 ohm/sq. Moreover, we also prepared the conductive pattern with a resistance of 3 ohm via desktop dispensing robot.

ABSTRACT. Biodegradable polymers have attracted a great deal of attention in decades owing to the environmental concern and sustainability issue. Among them, poly(lactic acid) (PLA) is the most used biodegradable polymer which is derived from renewable resources and considered as non-toxic for humans and the environment. However, it is well known that PLA is a brittle plastic with low resistance to fracture. We therefore tried to increase flexibility and toughness of PLA by melt-blending with other materials, including octadecenylsuccinic anhydride as a low-molecular-weight plasticizer, poly(hydroxybutyrate) as another biodegradable polymer, and a modified montmorillonite as an inorganic filler. Structures, thermal properties and mechanical properties of all these blends were investigated. Their mechanical properties revealed that the toughness could be improved to some extent by blending with these materials; and among them, the PLA/clay nanocomposite at 1 phr clay exhibited significant stress-whiting and necking behavior with a large extension, elongation at break being increased to 208%, up to 37-fold increment compared to the neat PLA.

ABSTRACT. An ability of using Cationic Starch as a material to replace a part of PAC chemical in the case of tackling the polluted wastewater from the fishery processing company with a high COD value by Coagulation-Flocculation Process is concerned in this study. the Jar-test was conducted for the optimal PAC concentration of 600mg/l used to solve, which was replaced a part of 25%, 50%, 75%, and 100% in the experiment, respectively. As the results denoted, it seemed not to be effective in reducing COD when using totally the cationic starch solution to treat the sample. Additionally, the ratio of 150 mg/l PAC solution mixed with 450 mg/l Cationic starch solution (1:3 ratio) was only 31.90 %, compared to the higher efficiency of the control sample with 48.14%. Meanwhile, the mixture of 1:1 ratio could treat better, 2.07 % higher than the control sample. Furthermore, the 3:1 ratio illustrated the value which reached a peak of 55.98%, making it become the optimal ratio of mixing two types of material.

ABSTRACT. Two carbazole-based molecule, i.e., PhCzp-Me and PhCzm-Me, were synthesized through metal-catalyzed coupling reactions. The maximum absorption band of PhCzp-Me and PhCzm-Me located at 348 nm and 298 nm, while the maximum emission band located at 371 nm and 369 nm, respectively. The density functional theory calculations showed that the dihedral angle of PhCzp-Me and PhCzm-Me are 52.9o and 92.9o. In the applications of OLEDs, we applied PhCzp-Me to co-deposit with CN-T2T to form excilplex as the emitting materials of OLEDs. The device with the structure ITO/HATCN (10 nm)/TAPC (35 nm)/PhCzp-Me (20 nm)/PhCzp-Me:CN-T2T 1:1 (30 nm)/CN-T2T (40 nm)/LiF (1 nm)/Al (100 nm) exhibited a maximum external quantum efficiency (EQE) of 5.7% with the maximum emission wavelength at 510 nm and CIE coordinate of (0.268, 0.512). Our results showed that PhCzp-Me and PhCzm-Me could form excilplex with CN-T2T and applied as the host or emitting materials for OLEDs with good device performance.

ABSTRACT. This research was carried out to apply non-invasive methods Ground-Penetrating Radar (GPR) technology in surveying underground constructions in Ho Chi Minh City. By using a GSSI (Geophysical Survey Systems) 350 MHz radio frequency GPR antenna. GPR uses safe low power radar pulses, transmitted into to the ground, then recovers the reflected energy resulting from dielectric contrasts in the subsurface layers. The survey was conducted by scanning perpendicular to the suspected pipeline, determining the location of the pipeline based on images displayed on a tablet. The location of the pipelines are displayed by hyperbola targets, caused by the change in dielectric (velocity) created as the antenna approaches and passes over the targets. This research has successfully determined the locations of 2 pipelines along all of the surveying area, with depths of 0.7 and 1.2m. From there, we can see the suitability, accuracy and value of the technology of using GPR technology in HCMC.

ABSTRACT. In this study, a series of 2,2′ and 3,3′ substituted thienoisoindigo (TII)-based small molecules (H3−H7) were synthesized by using 1,3-di(9H-carbazol-9- yl) benzene, N-phenylcarbazole, triphenylamine, and benzene as electron donor (D) at the periphery, while TII as electron acceptor (A) at the core. The highest occupied molecular orbital energy levels of H3−H7 range from −5.31 to −5.43 eV, while their lowest unoccupied molecular orbital energy levels range from −3.43 to −3.59 eV. Under AM 1.5 condition, the perovskite solar cell (PSC) with inverted p−i−n device structure using H7 as the dopant-free hole transporting material achieved a power conversion efficiency (PCE) of 12.1%, which is comparable to that using PEDOT:PSS as the hole transporting material (12.0%). Under an argon atmosphere, the PCE of H7-based PSC did not decay within 168 h, and it can retain 86.3% of its original PCE after 1000 h. The morphology study revealed that the film of H3−H7 was smooth and hydrophobic, while the perovskite film spin-coated on H3−H7 film was uniform with the grain size in micrometer scale. Although the time-resolved photoluminescence spectra of the perovskite films suggested that the hole extraction capability of H7 is weaker than that of PEDOT:PSS, the improved film morphology of the film in H7-based PSC accounts for its comparable PCE to PEDOT:PSS-based PSC.

ABSTRACT. Fishery processing byproducts have attracted numerous researches due to their great application in many fields. In this study, five kinds of marine chitinous byproducts including squid pens powder (SPP), shrimp shell powder (SSP), demineralized shrimp shell powder (deSSP), shrimp head powder (SHP), demineralized shrimp shell powder (deSSP) have been used to provide the carbon/nitrogen (C/N) source for producing a protease from Paenibacillus sp. TKU047. Paenibacillus sp. TKU047 possessed the highest protease productivity (2.98 U/mL) when cultured on the medium containing 0.5% of SHP for 2 days. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis revealed the molecular weight of TKU047 protease was approximately 32 kDa. TKU047 protease displayed the optimum activity at 70°C-80°C and pH 9 with a pH range of stability from 6 to 11. It was also found that TKU047 protease showed stability in the presence of detergents and surfactants. Base on their excellent properties, Paenibacillus sp. TKU047 protease may be a feasible candidate for inclusion in laundry detergent.

ABSTRACT. There has been a great increase in industrial applications of pectinase owing to their significant biotechnological uses. In this study, over 150 bacterial strains were isolated from Taiwanese soils using medium containing pectin as the sole source of carbon/nitrogen. Based on pectinase activity, TKU049 was selected for further study. Optimized culture conditions revealed TKU049 could produce the highest pectinase activity (1.18U/mL) when cultured in a medium containing 1.5% (w/v) pectin at 40℃ for 3 days. The purified pectinase exhibited optimum temperature of 60℃, optimum pH of 9, thermal stability of 20-50℃, and pH stability of 6-10. Also, the enzyme activity was found stimulated with Mn2+ metal ions. Moreover, it was stable on EDTA, Trixton-100, Tween 40, and Tween 20. After purification by Macro-Prep High Q chromatography, the fractions (fraction number 79-88) with pectinase activity were collected. The specific activity of pectinase was increased from 0.037 U/mg to 0.07 U/mg but the activity yield decreased dramatically from 21.7 % to 14.1 %. Further, HPLC analysis using KW802.5 column showed that the specific activity of pectinase was 0.04 U/mg and the activity yield was 1.1%.

ABSTRACT. In this study, production of Protease from SHP( shrimp head powde) by Some Paenibacillus and Bacillus Strains, SHP was used as the sole sources of C/N with concentration of 1%. After 3 days fermentation, the supernatants were tested for their protease activities using the assays mentioned in the materials and methods section. based on protease activity, Paenibacillus mucilaginosus TKU032 was selected for further study. TKU032 to Comparison Protease Production from Different Chitinous Materials Source in 0.5% SHP has the best Protease activity at 48 hours.The TKU032 protease exhibited optimum temperature of 50℃, optimum pH of 8, thermal stability of 10-50℃, and pH stability of 5-10. Also, the enzyme activity was found stimulated with Na2+ Ca2+ Fe2+ metal ions. In Substrate the azo casein better than the others.

ABSTRACT. The study of treating assumed wastewater with Ni2+ by using Biogum – a bio- material extracted from tamarind seeds. The term "Gums" is used to describe a group of natural polysaccharides containing glucose, xylose and galactose which are widely found in industrial applications due to their gel or viscosity capabilities. The analysis of infrared spectrum diagram shows that Biogum extracted from tamarind seeds has functional groups - OH, carboxylate −COO−, C - H in CH3, C - N in Amine aliphatic or in Alcohol. The best treatment efficiency of Ni2+ removal is at 50ml biogum at optimal pH of 5 and time of treatment reaching equilibrium at 60 minutes. The results are similar to previous studies and are applicable to the treatment of wastewater containing heavy metals.

ABSTRACT. Textile and dye industry play an important role to Vietnam’s economy. This industrial process consumes a huge volume of water, and also discharges a large amount of pollutants. Particularly, color pollution – a non-decomposable contaminant naturally, which is a vital of concern in treatment engineering. Several physio-chemical techniques were applied for removing color from wastewater with different advantages and disadvantages. However, adsorption technique by using bio-materials, which are environmentally friends, operation with ease, and reuse post-adsorptive materials, is a preferable approach to others. This present study used activated biochar by H3PO4 and denatured by HNO3, which made from seeds of Cassiatora Linn (Cassia fistula L.), for removing color of Methylene Blue (MB) in textile and dye wastewater. Scanning electronic microscopy (SEM) and Fourrier Transformation Infrared (FTIR) techniques were deployed to investigate the surface and structure of biochar. The results show that biochar activated by H3PO4 and denatured by HNO3 has an adsorption capacity at 20.974 mg/g and 25.013 mg/g, respectively. Performance results of SEM show denatured biochar has rough surface and hollowness, and FTIR results found function groups of O-H, C=C, C=O, and C≡C. These spell that activated biochar has a better color adsorption in comparison with other materials. Further, using adsorbent biochar (denatured by HNO3) for removing methylene blue at 50 mg/L, the removal efficiency is 99.229% after 60 minutes. This findings showed that biochar made from Cassia fistula L. has potential color adsorption, and is an initial investigation of future wastewater treatment applications for other industrial wastewater types

ABSTRACT. Polymers are almost the most important mass-produced materials in chemical industry. Alternative raw materials are required to ensure sustainable production of polymers and functional materials. After the discovery of inverse vulcanization, sulfur was used as the main component of the polymers and the elemental sulfur is produced in large quantities as a by-product of the petrochemical industry. However, sulfur cannot used to produce functional materials because decomposes back to its monomer since polymeric sulfur is unstable. To overcome this issue, inverse vulcanization technique has been used to produce stable polymeric materials containing high sulfur content. These polymers are used in some environmental processes by the advantages of sulfur’s high mercury and dye capturing property. The applications of these materials will be discussed by doing some literature research touching upon environmental benefits. The articles that are published between 2016 and 2019 in Royal Society of Chemistry about this subject are investigated.

ABSTRACT. 　Organic hydrides are known to be hydrogen carriers to achieve large-scale storage/transportation of hydrogen. Especially, toluene (TL)/methylcyclohexane (MCH) are a promising couple because both are liquids at ambient temperature and pressure to use existing infrastructure, and MCH has high hydrogen storage density. In general, MCH is regenerated by hydrogenation of TL with molecular hydrogen on appropriate catalysts. Molecular hydrogen needs to be produced by chemical or electrochemical methods. However, electrochemical hydrogenation of TL can regenerate MCH with atomic hydrogen, which is electrochemically formed, in one pot. The latter process is more energy-saving than the former process. Carbon-supported Pt nanoparticles (Pt/C) are active catalysts for electrochemical hydrogenation reaction of TL to MCH. To improve catalytic activity of Pt/C, we attempted the surface modification of Pt nanoparticles with rhodium because TL is adsorbed on it more strongly. In this study, we prepared Rh-modified Pt/C (Rh/Pt/C) catalysts and evaluated the effect of Rh modification on catalytic activity of Pt/C for direct electrochemical hydrogenation of TL. 　Some kinds of Rh/Pt/C catalysts were prepared by bubbling hydrogen in different concentrations of Rh precursor solutions containing Pt/C. X-ray diffraction patterns and X-ray photoelectron spectra showed Rh did not alloy with Pt. Transmission electron micrographs and energy dispersive X-ray line analysis exhibited Rh was deposited only on the Pt nanoparticles surface. In linear sweep voltammogram, the Rh/Pt/C catalysts had higher hydrogenation current density at 0 V vs. RHE than Pt/C. Furthermore, in the GC/MASS analysis, MCH was sole hydrogenation product. In galvanostatic electrolysis, the faradaic efficiency for MCH production and conversion of TL to MCH for the Rh/Pt/C catalysts were higher than Pt/C. These results clearly indicate that the Rh/Pt/C catalysts were superior to Pt/C.

ABSTRACT. Insulin stimulates glucose uptake in skeletal muscle and adipose tissue, thereby regulating the blood glucose level. Insulin-dependent glucose uptake in these tissues occurs via the translocation of the glucose transporter GLUT4 from intracellular storage vesicles to the plasma membrane. A signaling pathway consisting of phosphoinositide 3-kinase (PI3K) and the protein kinase Akt2 has been shown to play an important role in this insulin signaling. We have recently demonstrated that the Rho family small GTPase Rac1 is another key regulator that acts downstream of Akt2 in skeletal muscle insulin signaling. Although the uptake of glucose is also stimulated by insulin in adipose tissue, the role for Rac1 in adipocyte insulin signaling remains controversial. In this study, we aimed to clarify the role for Rac1 in insulin-stimulated glucose uptake in adipocytes. First, we examined activation states of Rac1 in mouse white adipocytes by an immunofluorescent microscopy-based assay, demonstrating that Rac1 was indeed activated following intraperitoneal injection of insulin. Furthermore, ectopic expression of constitutively activated PI3K and Akt2 induced Rac1 activation. Second, we tested whether GLUT4 translocation and glucose uptake in mouse white adipocytes are impaired by rac1 gene knockout. Intraperitoneal insulin injection stimulated GLUT4 translocation as determined by a reporter assay in control, but not rac1-knockout, mouse white adipocytes. On the other hand, ectopic expression of constitutively activated PI3K and Akt2 as well as intraperitoneal insulin injection enhanced 2-deoxy-D-glucose uptake in control white adipocytes. In contrast, all of these enhanced 2-deoxy-D-glucose uptakes were diminished in rac1-knockout white adipocytes. Collectively, these results provide evidence that Rac1 plays an important role in insulin-stimulated glucose uptake not only in skeletal muscle, but also in white adipocytes.

ABSTRACT. Direct glycerol fuel cell (DGFC) using glycerol, a by-product of biodiesel fuel production, is a promising device that can generate electricity with low environmental load and high energy efficiency. However, sluggish glycerol oxidation reaction (GOR) kinetics, low selectivity to carbonic and catalyst poisoning inhibit the practical use of DGFC. We found that Rh was a promising catalyst having smaller GOR overpotential than Pt, a common catalyst for alcohol oxidation reactions. Nevertheless, GOR current on Rh was much smaller than that on Pt, which is an issue to overcome. In this study, the electrochemical modification of Rh with some transition metals (Ag, Pt) (M/Rh) was employed to examine their effects on GOR activity. The presence of foreign metals was confirmed by X-ray photoelectron spectroscopy. GOR activity on bare polycrystalline Rh and M/Rh electrodes was evaluated from cyclic voltammograms in alkaline solutions containing glycerol at various temperatures. We found that GOR activity of Pt and Pd was significantly enhanced by Ag-modification, but the Ag-modification on Rh hardly amplified the GOR current and lowered the overpotential. Otherwise, Pt-modified Rh (Pt/Rh) demonstrated its effectiveness for intensifying GOR activity. The onset potential of GOR current for the Pt/Rh electrodes with different Pt deposition amounts shifted in the negative direction and the GOR current density also became 5 times higher than the bare Rh electrode. The activation energy for GOR, calculated at -0.4V (vs. Hg/HgO), was diminished with prolonging of Pt deposition period, which attributed to the increase of Pt surface area.

ABSTRACT. Foldamer, a molecule that adopts a specific folding conformation in response to external stimuli, has attracted much attention in terms of medical and optical functional field. To develop a novel foldamer, in this work, we synthesized a copolymer poly-1 composed of benzene and dithienyl ketone with triethylene glycol chains . The results of 1H NMR analysis indicate that poly-1 is a foldamer which forms random coil and helix conformations in less polar and polar solvents, respectively. The CD spectrum of a DMF/H2O solution containing poly-1 and (–)-α-pinene or L-serine exhibits distinct negative-to-positive Cotton effects in the visible wavelength region, which indicate an induction of M-handedness of the helix of poly-1. As a result of further study on the induction of helical chirality of poly-1, it is suggested that hydrophobic (–)-α-pinene interact with poly-1 both inside and outside the helix while hydrophilic L-serine interact with poly-1 only outside the helix. Interestingly, the dominant interaction of (–)-α-pinene with poly-1, in other words, the resultant helical chirality of poly-1 can be switched by changing solvent polarity, stoichiometry of (–)-α-pinene, and temperature.

ABSTRACT. Water and water environments play a special role in human life, on the other hand, society is growing, industrial waste is increasing along with the habit of discharging untreated waste, making lips school and water contaminated. Therefore, saving and protecting water resources is becoming a big problem for the community. The paper presents methods of treatment, sedimentation, filtration and reuse of wastewater, after washing and washing stations, by methods: reverse circulation and reverse osmosis, will help save water resources, types removal: oil, grease, mud, soil and organic pollutants, before being discharged into the environment

ABSTRACT. Increasing in urbanization and agricultural activities has resulted in the deterioration of Saigon river water, one of the crucial water supply sources for Ho Chi Minh City. The presence of elevated concentrations of natural organic matter, together with other contaminants, has induced a requirement for pre-treating the raw water before entering conventional treatment processes. At Tan Hiep water treatment plan, the raw water is pre-treated through chlorination. This process is not only costly but also creates favorable conditions for the formation of harmful disinfectant by-products (DBPs). Therefore, the removal of natural organic matter (NOM), a DBP, from Saigon river water is needed. However, the current understanding of this specific NOM is minimal since most of the studies in the literature have been working with Suwannee River Humic Acid (SRHA) and commercially available ones. Therefore, this study aims to characterize the properties of the Saigon River humic acid (SGRA). From this information, the technology tailored for efficient removal of this specific SGRHA could be developed. In addition, a better understanding of SGRHA is beneficial for modeling the fate and transport of contaminant in the Saigon River.