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Hellula undalis is a harmful insect pest of green mustard in the Mekong Delta of Vietnam. In order to establish a tool for a sustainable pest control program, the sex pheromone of H. undalis inhabiting the Mekong Delta was examined. GC-EAD and GC–MS analyses of pheromone gland extracts from the virgin females elucidated three new components, (Z)-11-tetradecenyl acetate (Z11-14:OAc), (Z)-11-hexadecenal (Z11-16:Ald), and (11E,13E)-11,13-hexadecadien-1-ol, in addition to the known pheromone component (11E,13E)-11,13-hexadecadienal (E11,E13-16:Ald). Double bond positions of the two monoenyl components were determined by GC–MS analysis of the pheromone extract treated with dimethyl disulfide. On the other hand, GC–MS analysis of the female body extract detected the unsaturated hydrocarbon (3Z,6Z,9Z)-3,6,9-tricosatriene (Z3,Z6,Z9-23:H). Field examinations of their synthetic compounds indicated the significant role of E11,E13-16:Ald as a major component and a clear synergistic effect of the two monoenyl compounds as a minor component. Although the 3:3:7 mixture of Z11-14:OAc, E11-16:Ald, and E11,E13-16:Ald captured the largest number of males among the tested mixtures, the activity was still quite a bit lower than that of virgin females. However, the 3:3:7:1 mixture, which was prepared by adding a small amount of Z3,Z6,Z9-23:H to the 3:3:7 ternary lure, succeeded in attracting males more powerfully than the females did. This strong synergistic effect was not observed when the triene was added to unmixed E11,E13-16:Ald, indicating important roles of not only the triene but also the two monoenyl compounds as natural pheromone components.

Ageratum conyzoides is an herbaceous plant widely used in traditional medicine against various diseases, and possesses anti-inflammatory, anti-ulcer, analgesic, and diuretic properties. However, its effects on endoplasmic reticulum (ER) stress, as observed in diseases such as diabetes, have not yet been characterized. In this study, using mouse pancreatic Beta-cells, we demonstrated that the ethanol extract of A. conyzoides effectively suppressed cell death induced by ER stress. Four polymethoxyflavones (PMFs) including (1) 5,6,7,3′,4′,5′- hexamethoxyflavone; (2) 5,6,7,8,3′,4′-hexamethoxyflavone (nobiletin); (3) 3′,4′-methylenedioxy-5′,5,6,7- tetramethoxyflavone; and (4) 5,6,7,8,5′-pentamethoxy-3′,4′-methylenedioxyflavone were isolated from the ethyl acetate fraction using reverse-phase chromatography. Their structures were elucidated using spectroscopic and mass-spectrometric analyses including 1D-, 2D-NMR, and HRESI-MS. All compounds were further evaluated for their ability to inhibit ER stress. Our results suggested that only compound 1 did not show an ability to rescue ER stress-induced cell death. Additionally, compound 2 as a nobiletin and its commercial product alleviated the tunicamycin-dependent chop mRNA expression induction. Notably, extremely low concentrations of both compounds exerted cytoprotective activity against tunicamycin-induced ER stress in pancreatic Beta-cells

This paper presents modelling and experimental validation for improving the performances of a marine diesel generator engine. Based on the diesel engine theory, the laws of conservation of energy, and the principle of movement of flow through turbocharger nozzle, a mathematical model of a real turbocharged engine was built, concentrating on the mathematic model of flow through nozzles. This model is simulated by Matlab/Simulink program, the results of simulation showed the relationships between the engine and the turbocharger, the turbine and the compressor, and between the nozzles and the turbocharger. The experiments were carried out to validate this model, the errors between the simulation and measure were acceptable. The measure and simulation results also determined that at the low load conditions (≤50% load) engine performances can be improved by adjusting nozzle opening degree (from fully opening to 90% and 80% opening).

Blast disease and sheath blight disease caused by infection with Pyricularia oryzae and Rhizoctonia solani, respectively, are serious fungal diseases in paddy fields. Although synthetic fungicides have been used to control these diseases, the development of ecologically friendly alternatives is required because fungicides can cause health problems and environmental pollution. Natural herbs possessing antifungal activities are among the candidates as alternatives. Ageratum conyzoides is known to contain antifungal compounds, such as precocene II and polymethoxyflavones. Here, we report the antifungal activities of five compounds isolated after ethanol extraction from Ageratum conyzoides against Pyricularia oryzae and Rhizoctonia solani in vitro. Further, we demonstrated the protective effect of the extract on rice from Pyricularia oryzae infection by field trial testing in a shaded net-house.

We know the development trend of industries in general and the shipbuilding industry, in particular, is the increase in energy efficiency to contribute to global emissions reduction, especially CO2 emissions. It is not difficult to realize that gas turbines utilize exhaust gas energy to increase the intake air pressure. Exhaust gas turbines are convenient enough to complete the shipbuilding industry in line with the norms of the world maritime organization, including EEDI (energy efficiency design index) and SEEMP (ship energy efficiency management plan). Thus, satisfying IMO's EEDI and SEEMP criteria under MARPOL Annex VI, the completion of the design and exploitation of turbocharged exhaust turbines should be a top priority. Exhaust gas turbines increase the intake air pressure to improve the performance of diesel engines, so it is almost present on most diesel engines. Mastering the structure and working principles to improve the efficiency of turbines continuously is an urgent requirement. Besides, it is necessary to follow the manufacturer's instructions and research to effectively exploit turbines that will contribute to increasing economic efficiency and contributing to reducing environmental pollution emissions. The article focuses on analyzing measures to overcome the causes of working instability of the main diesel engine's exhaust gas turbine, which will contribute a small part in completing exhaust gas turbines. Based on mastering the knowledge of exhaust gas turbine, we can choose the turbine layout to utilize exhaust gas heat suitable for diesel engines. Moreover, mastering the factors that affect the working of turbines and compressors, thereby improving the quality of turbine extraction and maintenance to ensure they always work in the best conditions.

Deposit, which is found in the combustion chamber of the internal combustion engines after operating hundred hours, causes many various issues such as reduce in the engine power and performance, reduce in ability of heat transfer, reduce in conduction rate but increase in toxic emissions content. Deposits accumulating in the end gas areas, on exhaust valves, and in cylinders with high oil consumption can be distinguished by comparison of H/C atom ratios, carbon content and inorganic compound content. Differences in deposit composition can be observed between engine families and between driving cycles with the same engine family. Besides, deposit also causes the jam between the motive mechanical parts in engine combustion chamber, even cause the abnormal combustion. The study of deposit formation and structure is necessary in order to find out the method aiming for overcoming the negative influence on the engines. The paper presents a review of deposit, the deposit formation and structure are mentioned by many researches and aggregated in this work. Findings of paper not only enrich the knowledge about the engine deposit but also are potential to carry out an experimental set up in order to estimate, calculate the ability of forming the deposit on a same condition as in the engine combustion chamber.

On ships, boilers are used for many purposes: Supplying steam to the main steam turbine to drive the propeller to create thrust, drive generators, drive pumps and winches. Also, it has a role to drive trouble equipment, provide steam for heating lubricants, fuel, steam supply for air conditioning systems for crew members ... With so many important uses, ensuring good operation of the boiler is a matter of primary concern for operators. In the operation of the boiler, controlling the water levels ensures not only good steam generation but also operator safety as well as the boiler itself. Automatic control of the water supply process is an important part of the boiler control system. This system has the function of maintaining a stable water level in the boiler. Currently, fuzzy control theory, whose mathematical tool is the fuzzy set theory of L.A Zadeh is being developed strongly. Different from the old control technique that relies purely on the absolute accuracy of the information that many applications cannot, the fuzzy control can handle unclear information. Information that their accuracy is only recognized by their relations with each other and can only be described in the control language. Fuzzy control allows copying personal information processing and control methods to solve complex control problems. The paper focuses on research to use fuzzy control theory combined with traditional PID controller to achieve optimal quality control for the process of adjusting the boiler water level. Construct a fuzzy controller to adjust parameters of the PID water level controller to optimize the process of adjusting the boiler water level. Simulation of water level control of fuzzy PID control on Matlab-Simulink software.

Citripestis sagittiferella is one of the most harmful pest insects of pomelo in the Mekong Delta of Vietnam. In order to utilize sex pheromone as tool for population monitoring by which supplies information for timing control, the sex pheromone of C. sagittiferella was preliminarily identified then tested under field condition. Fruits infected C. sagittiferella larvae were collected from pomelo orchards in Vinh Long and Hau Giang provinces and brought to Can Tho University laboratory for rearing to extract the pheromone. The analysis was conducted by GC-EAD, GC-MS and the double bond position was affirmed by analysis of its DMDS adduct. GC-EAD analysis resulted in three EAG-responses, namely component I (Comp. I), Comp. II and Comp. III. Mass spectra with diagnostic ions at m/z 61, 194 and 192 ([M-60]+ ions) indicated that they were unsaturated 14 carbons (C14) straight chain acetates. Reference to the synthetic standards by both GC-EAD and GC-MS analysis confirmed that the three pheromone components were (E)-11-tetradecenyl acetate (E11-14:OAc), (Z)-11-tetradecenyl acetate (Z11-14:OAc) and (9Z,11E)-9,11-tetradecadienyl acetate (Z9, E11-14:OAc), respectively. Unfortunately, lures prepared from mixtures of synthetic E11-14:OAc, Z11-14:OAc and E9, Z11-14:OAc at several mixing ratios showed no attraction to C. sagittiferella males in field tests.

We demonstrated that a spray treatment of rice flowers with the spores of nonpathogenic fusaria mimicked the disease cycle of the seed-borne bakanae pathogen Fusarium fujikuroi and effectively suppressed the disease. Spray treatment of nonpathogenic fusaria reduced the degree of pathogen invasion of rice flowers and vertical transmission of the pathogen to the next plant generation via seeds, thereby controlling the bakanae disease. The most promising isolate, F. commune W5, colonized seeds and seedlings via treated flowers and successfully inhibited pathogen invasion, suggesting that competition with the pathogen was the mode of action. Seed-borne diseases are often controlled by seed treatment with chemical fungicides. Establishing an alternative method is a pressing issue from the perspectives of limiting fungicide resistance and increasing food security. This work provides a potential solution to these issues using a novel application technique to treat rice flowers with biocontrol agents., Bakanae disease, caused by Fusarium fujikuroi, is an economically important seed-borne disease of rice. F. fujikuroi is horizontally transmitted to rice flowers and vertically transmitted to the next generation via seeds. The fungus induces typical symptoms such as abnormal tissue elongation and etiolation. Sanitation of seed farms and seed disinfection are the only effective means to control bakanae disease at present; however, the efficacy of these methods is often insufficient. Therefore, alternative and innovative control methods are necessary. We developed a novel method for applying nonpathogenic fusaria as biocontrol agents by spraying spore suspensions onto rice flowers to reduce the incidence of seed-borne bakanae. We visualized the interaction between Fusarium commune W5, a nonpathogenic fusarium, and Fusarium fujikuroi using transformants expressing two different fluorescent proteins on/in rice plants. W5 inhibited hyphal extension of F. fujikuroi on/in rice flowers and seedlings, possibly by competing with the pathogen, and survived on/in rice seeds for at least 6 months. IMPORTANCE We demonstrated that a spray treatment of rice flowers with the spores of nonpathogenic fusaria mimicked the disease cycle of the seed-borne bakanae pathogen Fusarium fujikuroi and effectively suppressed the disease. Spray treatment of nonpathogenic fusaria reduced the degree of pathogen invasion of rice flowers and vertical transmission of the pathogen to the next plant generation via seeds, thereby controlling the bakanae disease. The most promising isolate, F. commune W5, colonized seeds and seedlings via treated flowers and successfully inhibited pathogen invasion, suggesting that competition with the pathogen was the mode of action. Seed-borne diseases are often controlled by seed treatment with chemical fungicides. Establishing an alternative method is a pressing issue from the perspectives of limiting fungicide resistance and increasing food security. This work provides a potential solution to these issues using a novel application technique to treat rice flowers with biocontrol agents.

Ships are a significant source of pollution to the environment, especially in port and coastal cities because they use poor quality mineral fuels, have very high emissions such as a nitrous oxide (NOx), sulfur dioxide (SO2). As an indisputable fact, the combustion of the mixture of fuel and air in the combustion chamber is always accompanied by the oxidation of nitrogen; nitrogen oxide products will always accompany the combustion product. The International Maritime Organization (IMO) is increasingly tightening emission regulations with shipping fleets, especially NOx emissions. For marine diesel engines, the NOx emission limit is set by Article 13 of Annex VI of MARPOL 73/78 and takes effect as of January 1, 2000. There are many solutions to reduce NOx emissions at the generating source, such as reducing early injection timing, exhaust air recirculation, water injection into the cylinder, … NOx adjustment solutions for diesel engines have been applied since MARPOL Article 13 came into effect. These solutions can be achieved by increasing the compression ratio, slowing the injection delay, and modifying the distribution phase of the exhaust. Emission circulation is a technique used to reduce emissions of nitrous oxide (NOx) on various types of marine engines. This EGR emissions system is used in conjunction with other emission control devices, such as exhaust catalytic converters to help minimize environmental emissions from marine engines. The paper presents the results of evaluating the effect of exhaust gas recirculation on the economic, energy, and environmental criteria of marine diesel engine 6CHHSP 18/22-600 through a work cycle simulation model built into dedicated AVL-Boost software.

Bacterial leaf blight and blast diseases caused by the bacterium Xanthomonas oryzae pv. oryzae and the fungus Pyricularia oryzae, respectively, are among the most important infectious diseases affecting rice. We evaluated the antimicrobial effects of compounds derived from Praxelis clematidea on Xanthomonas oryzae and Pyricularia oryzae. The dried aerial parts of Praxelis clematidea were subjected to ethanol extraction, separated by solvent partitioning using hexane, chloroform, ethyl acetate, and water. In vitro assays demonstrated that the main antibacterial and antifungal activities were distributed in the ethyl acetate and chloroform fractions, respectively. These fractions were further separated using silica gel chromatography and reversed-phase chromatography. Finally, we isolated five compounds, 1–5, that inhibited the growth of Xanthomonas oryzae in vitro and four compounds, 6–9, that exhibited in vitro antifungal activity against Pyricularia oryzae. We evaluated their antimicrobial activities and identified their chemical structures by NMR and mass spectrometry analyses. This is the first study to isolate compound 2 (4,4′,4″-nitrilotriphenol) as an alternative microbial from natural resources and evaluate its physiological activity. Moreover, this is the first report to demonstrate antibacterial activity in comparison with flavonoids. Praxelis clematidea extracts plausibly exert both antibacterial and antifungal effects, which should be further validated in field trials.

Fossil fuel crisis and depletion, environmental pollution and ever-increase in vehicle and transportation means have renewed the scientist’s interest in the world in order to look for potential alternative fuels, which are attractive such as biodiesel, bioethanol, DME and vegetable oils. Inedible vegetable oils such as coconut oil, Jatropha oil, linseed oil or animal fat are full of potential for using directly or manufacturing biodiesel. This work is carried out in order to study the four stroke diesel engine D240 performance characteristics fueled with preheated pure coconut oil (PCO), Jatropha oil methyl ester (JOME) and compare with diesel oil (DO). The test diesel engine performance such as power (Ne), torque (Me), specific fuel consumption (ge) and thermal efficiency (ηe) is determined, calculated and evaluated while using JOME, preheated PCO and compared to DO. The results show that, power (Ne), torque (Me) and thermal efficiency (ηe) while engine is fueled with JOME and PCO are lower, otherwise specific fuel consumption (ge) is higher than those of diesel fuel, the test engine performance are gained the best for JOME and PCO100. Keywords: biofuel, biodiesel, preheated vegetable oils, engine performance, efficiency, specific fuel consumption. Article History : Received Dec 9, 2016; Received in revised form January 28, 2017; Accepted February 4, 2017; Available online How to Cite This Article : Hoang, T.A and Le,V. V. (2017). The Performance of A Diesel Engine Fueled With Diesel Oil, Biodiesel and Preheated Coconut Oil. International Journal of Renewable Energy Development, 6(1), 1-7. http://dx.doi.org/10.14710/ijred.6.1.1-7

Leucinodes orbonalis is one of the most damaging insect pests affecting eggplant in the Mekong Delta of Vietnam. While (E)-11-hexadecenyl acetate (E11-16:OAc) and its alcohol, (E)-11-hexadecenol (E11-16:OH), have been identified as major and minor sex pheromone components, respectively, few males were attracted to a blend of these compounds in Vietnamese fields. In order to utilize synthetic pheromone of L. orbonalis as a tool for sustainable pest management programs, we reexamined the pheromone of this species in order to search for other minor components. Gas chromatography-electroantennogram detection and gas chromatography/mass spectrometry analyses of abdominal tip extract revealed the presence of two electroantennogram-active compounds, E11-16:OAc and (3Z,6Z,9Z)-3,6,9-tricosatriene (Z3,Z6,Z9-23:H) in a ratio of 100:2. An extract of the abdomen and thorax showed an additional electroantennogram-active component, (3Z,6Z,9Z)-3,6,9-docosatriene (Z3,Z6,Z9-22:H), with the three compounds (E11-16:OAc, Z3,Z6,Z9-23:H and Z3,Z6,Z9-22:H) being present in a ratio of 100:45:1, indicating that the trienes were mainly present on the cuticular surface. In the field, traps baited with E11-16:OAc and the C23 triene, in a mix of 10:1, caught more male moths than traps baited with the acetate alone. A field evaluation of other polyunsaturated hydrocarbons showed that the C22 triene found in body extract also increased catches when added to the acetate, but no other hydrocarbons did. In contrast, to other studies with this moth, the addition of E11-16:OH to E11-16:OAc plus the C22 or C23 triene, resulted in decreased trap catches.