Effect Of Promotion On Customers’ Trust Organic Food In The Mekong Delta

The customer’s trust is seen as a key for the survival to any enterprises wanting to maintain sustainably in the competitive market at present time. Enterprises need to experience ceaseless efforts to gain their customer’s trust. In addition, the quality of the product, there are many other factors contributing to build and strengthen the trust of consumers. This study is to determine factors of marketing activities which have impacts on the trust of organic food in The Mekong Delta. The study was conducted with two promotion tools (advertisement and PR), surveyed 300 subjects in the Mekong Delta region, Vietnam. Descriptive statistics, EFA analysis and MLR regression analysis were used to find the advertisement and PR’s impact on the customer’s trust. The analysis results showed, form of public relations, the usefulness of public relations activities, the quality of information from public relations activities have great impacts on customers’ trust. This means that when the customer feels good about the above-mentioned factors, the higher the trust they have on the product. Based on the results, the author proposed solutions to gain greater trusts from customers. For instance, it is necessary to have a careful study on target customers’ psychology, preferences and habits when they approach advertising media and their perceptions of the frequency of advertising. The enterprises need to provide advertising information in a full and honest manner. They should develop PR programs that focus on usefulness for the target audience and the community

Corrosion protection of carbon steel by an epoxy resin containing organically modified clay

This study focusses on the use of montmorillonite clay (MMT) treated with an organic compound (aminotrimethylphosphonic acid (ATMP)) and dispersed in an epoxy resin to improve corrosion protection of carbon steel. X-ray diffraction was performed to verify that the individual silicate layers were separated and dispersed in the epoxy resin. Corrosion resistance of the coated steel was evaluated by electrochemical impedance spectroscopy (EIS) and local electrochemical impedance spectroscopy (LEIS). Three systems were tested: the epoxy clear-coat, the epoxy resin containing 2 wt.% clay and the epoxy resin containing 2 wt.% clay modified byATMP (ATMP-modified clay). From conventional EIS, it was shown that the incorporation of clay or ATMP-modified clay in the epoxy matrix significantly improved the barrier properties of the coating. The corrosion resistance of the carbon steel coated by the epoxy resin containing ATMP-modified clay was higher than that obtained for the system containing non-treated clay. Local electrochemical measurements performed on scratched samples revealed the inhibitive role of ATMP at the carbon steel/coating interface

Experimental study on transverse behavior of concrete box girder bridges with strutted wing slabs

In 2023, the first box girder bridge with strutted wing slabs in Vietnam was put into use in the Ring Road II Viaduct Project in Hanoi. As this is an innovative type of traditional box girder bridges and completely new in Vietnam, prior to the commencement of the project, an experimental program was conducted to check the construction technology and obtain valuable experimental data for design and further numerical analyses. A full-scale girder segment with a width of 18.7 m, a length of 6 m and height of 2.5 m, incorporating steel pipe struts, was fabricated. Three distinct load cases were conducted to investigate the transverse behavior of strutted wing slabs, steel pipe struts and connections under the most unfavorable load conditions at Service Limit State. This paper presents a detailed experimental program with test results.  It is shown that with applied loads varying from 1.2 to 1.5 times the service load, both the deck slab and steel pipe struts still exhibited linear manner, maintaining sufficient load-bearing capacity. However, with increased applied load in Load Case 2, cracks occurred along the construction joint region, indicating that attention to construction joint quality in real projects is needed to pay great attention to ensure the integrity of structures. Based on the conducted experiment, some recommendations are proposed for future implementation of such bridge typologies

Layered double hydroxides as containers of inhibitors in organic coatings for corrosion protection of carbon steel

The present work focuses on the use of layered double hydroxides (LDH) as containers for corrosion inhibitors in an epoxy coating. 2-Benzothiazolylthio-succinic acid (BTSA), used as corrosion inhibitor, was intercalated by co-precipitation in magnesium-aluminum layered double hydroxides. The obtained LDH-BTSA was characterized by infrared spectroscopy, X-ray diffraction and scanning electron microscopy. BTSA release from LDH-BTSA in NaCl solutions was investigated by UV-vis spectroscopy. The inhibitive action of LDH-BTSA on carbon steel corrosion was characterized by electrochemical methods and the protective properties of an epoxy coating containing LDH-BTSA were evaluated by electrochemical impedance spectroscopy. It was shown that the BTSA was intercalated in the layered double hydroxide and its loading was about 33%. The BTSA release was dependent on the NaCl concentration in the electrolyte. The polarization curves obtained on the carbon steel sample showed that the LDH-BTSA is an anodic inhibitor. Its efficiency was about 90% at a concentration of 3 g/l. The impedance results showed that the incorporation of LDH-BTSA (3%) in the epoxy matrix improved the corrosion protection of the carbon steel

Screening for actinomyces isolated from soil with the ability to inhibit Xanthomonas oryzae pv. oryzae causing rice bacterial blight disease in Vietnam

Bacterial blight disease caused by Xanthomonas oryzae pv. oryzae (Xoo) is one of the major diseases in rice culture of Northen Vietnam, as well as other rice-growing regions of the world. In this study, we isolated and screened for actinomycete strains from Vietnam with the ability to inhibit Xoo isolates from northern Vietnam. From 90 actinomycete strains taken from soil in northern Vietnam in 2010, we screened for their antagonistic activity against 10 races of Xoo causing rice bacterial blight disease. Three actinomycete strains were found to inhibit all 10 Xoo races. Among the three strains, a strain namely VN10-A-44 was shown not to have the ability to produce toxic compounds and was selected for further study. The strain was identified as Streptomyces virginiae by 16S ribosomal RNA gene sequencing. We replaced soybean meal with tofu waste in antibiotic producing medium to improve antagonistic activity of VN10-A-44 against the Xoo pathogen and to make use of tofu waste for large-scale fermentation of VN10-A-44. We found that replacing soybean meal with 20 and 30 g of tofu waste/litter in the antibiotic producing medium gave the largest inhibition zone against the Xoo pathogen.Key words: Xanthomonas oryzae pv. oryzae, rice bacterial blight disease, Streptomyces virginiae, Vietnam

Incorporation of an indole-3 butyric acid modified clay in epoxy resin for corrosion protection of carbon steel

In the present work, indole-3 butyric acid (IBA) was inserted between montmorillonite clay platelets by cation exchange. The clay treated with the organic compound (IBA-modified clay) was then dispersed in an epoxy resin at a low concentration (2 wt.%). IBA was chosen to act both as an inhibitor and an adherence promoter. The effect of the IBA-modified clay on the microstructure and on the protective properties of the epoxy coating deposited on carbon steel was evaluated by a thermostimulated-current (TSC) method and by electrochemical impedance spectroscopy (EIS). The TSC measurements showed the specific action of IBA-modified clay which decreased the molecular mobility of the polymer chain by comparison with the pure epoxy. Impedance measurements corroborated the role of the modified clay on the barrier properties of the coating which remained high as a function of exposure time in a 0.5 M NaCl solution. The corrosion resistance of the carbon steel coated with the epoxy resin containing IBA-modified clay was significantly higher than that obtained with the clear coat. Polarization curves plotted in the presence of an artificial defect demonstrated the inhibitive role of IBA at the carbon steel/coating interface. The good adherence of the coating was seen during salt spray test

LIGNANS FROM LEAVES OF AMESIODENDRON CHINENSE AND THEIR CYTOTOXIC ACTIVITY

ABSTRACTFrom leaves of Amesiodendron chinense (Mer.) Hu four lignans (+)-aptosimon (1), (+)-isolariciresinol (2), (-)-cleomiscosin A (3), and (-)-cleomiscosin C (3) were isolated. Their structures were determined by spectroscopic analysis including MS, 1D and 2D NMR as well as by comparison with reported data in literature. All compounds were evaluated for cytotoxic activities against five human cancer cell lines, KB, SK-LU-1, MCF-7, HepG-2, and SW-480. They showed weak cytotoxic activity on five tested human cancer cell lines with IC50 values ranging from 32.61 to 95.18 µg/ml

Fabrication of silver-nanoparticles-embedded polymer masterbatchs with excellent antibacterial performance

In the present work, a versatile and effective synthesis method of the silver-nanoparticles-embedded polyethylene (PE)-based polymer masterbatchs was demonstrated. Antibacterial investigations revealed that the nano-silver masterbatchs consisting of oleate capped silver nanoparticles dispersed in PE polymer matrix exhibited excellent antibacterial performance against Gram-negative Escherichia Coli (E.coli) and Staphylococcus aureus (S. aureus) bacteria.  A complete inhibition in bacteria growth was found at a silver nanoparticles concentration as low as 600 ppm. The origin of bactericidal effect and interaction mechanism of the stabilized silver nanoparticles with the Gram-negative E. coli and Gram-positive S. aureus bacteria can be understood in the light of electron microscopic observation. These advances make the synthesized nano-silver masterbatchs ideal for mass production of effectively antibacterial green products in medical, biological and industrial sectors. The type of polymer resin and silver concentration can be adjusted depending on the application area