Evaluation of organochlorinated pesticide residue in the water of Ba Tri agricultural canal Ben Tre province

The residues of Organochlorine pesticides from the water of the agricultural canal and river in Ba Tri district, BenTre province were determined by gas chromatography with electron- capture detector. The solid phase extraction (SPE- C18) cartridge was applied to extract organochlorine pesticides residues in water samples. The samples were collected during the dry, wet season and the crop growing 2006-2007. The results showed that most of water samples were contaminated with pesticide at concentration from 0.01 to 2.00 ppb. The residue of pesticides in water mainly depended on the crops season and have highest value in the beginning of growing period. The concentration of pesticides residues decreased from rice- field to canal and river. There were many forbidden pesticide such as HCH, Endosulfan, Heptachlor, Dieldrin etc. have been found with high frequency in water. It causes a big risk for human heath and aquatic biota

Reservoir simulation studies of formation damage for improved recovery on oil-gas reservoirs.

This thesis is dedicated to the development of new technologies for sweep improvement due to plugging of highly permeable channels and layers by injected or lifted or mobilized fines particles. The following methods of improved waterflood have been proposed in the thesis: • Injection of raw or poorly treated water with consequent homogenization of the injectivity profile due to distributed along the well skin factor. • Injection of low salinity or fresh water resulting in lifting of reservoir fines, their migration and further capture by the rock with permeability reduction and redirection of the injected water into unswept area. • Injection of sweet water into watered-up abandoned wells during pressure blowdown in oil and gas reservoirs with strong water support. In the above three cases, the proposal of the new technologies was backed by detailed reservoir simulations. In all cases, the application of the proposed improved oil recovery technology, as forecasted by reservoir simulation, leads to 3-15% of incremental recovery and 2-3 times decrease of the amount of produced and injected water. The technology of raw water injection was developed using Eclipse waterflood BlackOil simulator with modelling of injectivity decline along the well due to plugging of porous media by injected particles. A new numerical procedure describing skin growth with time in each section of long horizontal wells have been developed and implemented into BlackOil Eclipse model. Different configurations of horizontal injectors and producers have been modelled resulting in production forecast with raw waterflooding. The technology of low salinity water injection have been developed using Eclipse reservoir modelling with polymer injection option, which can describe mobilization of fines particles, their migration, capture and subsequent permeability decline. The main physics mechanism of incremental oil recovery found is the diversion of the injected water into unswept zones due to plugging the swept zone by capture particles. The incremental recovery, as obtained by reservoir simulation, is 12%. It may also result in 2 to 3 times decrease in water injection and production. The proposal of a new technology of small bank of fresh water injection into watered-up and abandoned production wells result in lifting of reservoir fines, their migration and plugging the path for invaded aquifer water. It results in decrease of water production and prolongation of oil or gas production from wells.Thesis (M.Eng.Sc.) -- University of Adelaide, Australian School of Petroleum, 201

The study of convex-dual-layer remote phosphor geometry in upgrading WLEDs color rendering index

The white-light light-emitting diode (LED) is a semiconductor light source that usually has one chip and one phosphor layer. Because of that simple structure, the color rendering index (CRI) is really poor. Therefore, structure with double layer of phosphor and multiple chips has been studied with the phosphorus proportions and densities in the silicone are constantly changed to find the best option to improve optical properties. In research, we use red phosphor Ca5B2SiO10:Eu3+ layer to place above the yellow phosphor one, and both of them have a convex design. Then, the experiments and measurements are carried out to figure out the effects of this red phosphor as well as the convex-double-layer remote phosphor design on the LED’s performances. The measured results reveal that the light output is enhanced significantly when using convex-dual-layer structure instead of the single-layer design. Additionally, the Ca5B2SiO10:Eu3+ concentration benefits CRI and CQS at around 6600 K and 7700 K correlated color temperature (CCT). Yet, the lumen output shows a slight decline as this red phosphor concentration surpass 26% wt. Through the experiments, it is found that a double layer of chip and double phosphorus is the best structure which could support the quality of CRI and luminous flux

Factors Affecting Business Angels Investment in Vietnam

The paper aims at investigating and comparing the factors determining investment decisions by business angels (BAs) from the viewpoints of BAs and startups in Vietnam based on a framework synthesized from a literature review and primary data from in-depth interviews conducted with 8 startups and 15 angel investors. The results show that the startups’ founder, working team, financial issues, product and market, and strategy related to exit and the roles of BAs are startup-related factors determining BAs’ investment in Vietnam. For BA-related factors, the BAs’ experience, investment objectives and preferences, and culture are key determinants. The novelty of the paper is to find out the gaps between the perspectives of BAs and startups, and the difference between Vietnamese and foreign BAs’ viewpoints. The finding is that BAs, more strictly than startups, assess their business plan, financial state, product, market, and targeted consumers. Startups neglect the exit strategy and role of BAs in invested startups. In addition, foreign and domestic BAs have different opinions on startups’ market scale, and expectation of profits and BAs’ roles in startups. The paper ends by providing some implications for Vietnamese startups to attract more angel investment, focusing on improving the quality of human resources, developing a profitable, honest, and realistic business plan, and setting up a long-run vision towards the global market. Doi: 10.28991/ESJ-2023-07-02-07 Full Text: PD

IMPACT OF THE EVFTA AGREEMENT: A STUDY ON VIETNAM'S EXPORTED GOODS

Abstract The research aims to assess the quantitative impact of the Vietnam-European Union Free Trade Agreement (EVFTA) on Vietnam's export growth to the EU market. The study employs quantitative analysis using the SMART model with data on export turnover and scenarios of tariff reduction to 0% when EVFTA takes effect. Based on the export turnover data and necessary parameters, the analysis results show an increase in Vietnam's exports to the EU market when EVFTA becomes effective. As a result, the research proposes some implications to promote Vietnam's export activities to the EU in the future

The Impact of Education on Child Abuse Prevention

This research investigates the impact of education on child abuse prevention in Vietnam by using Vietnamese government's reports (2012 – 2019) on child abuse. In order to analyze the impact of education on child abuse prevention, this study focuses on reviewing the previous policies in preventing child abuse, surveying three main determinants of parents, teachers and children and testing the data collected from the survey. The result shows that education plays an important role in improving the ability to take actions against child abuse. Some recommendations to parents, teachers, children and the government are also proposed for encouraging improvements in child abuse prevention education. Keywords: Child Abuse Prevention, Education, Vietnam DOI: 10.7176/EJBM/12-20-09 Publication date:July 31st 202

CHOOSE REMEMBERSHIP REMEDIES TO IMPROVE THE HAPPINESS OF FEMALE OFFICERS AND OFFICERS UNIVERSITY OF FITNESS AND SPORTS DA NANG, VIETNAM

Happiness has long been a veritable area of scientific research in most industrialized countries. Using the method of synthesis of documents and interview method, the study investigates the current state of happiness of 30 female officers and employees of Danang University of Physical Education and Sports using the author's happiness scale. Michael Argyle and Peter Hills (2002) have shown: 30.0% less are happy; 43.33% are happy on average; 26.67% are moderately happy; the most important factor in happiness is health. Subject-selected measures that can increase happiness are finding moments with loved ones in the family; practising more positive thinking; accepting the reality of the situation; join arts and sports clubs