Effect of the Morphological Characteristic and Composition of Electrospun Polyvinylidene Fluoride/Graphene Oxide Membrane on Its Pb2+ Adsorption Capacity

Thuy Thi Thu Nguyen,Huu The Nguyen,Hai Thi Trinh,Trang Thi Thu Bui,Anh-Tuan Le,Tran Quang Huy 한국고분자학회 2022 Macromolecular Research Vol.30 No.2

In this study, the Pb2+ adsorption capacity of electrospun polyvinylidene fluoride/graphene oxide (PVDF/GO) membranes with different morphological characteristics and compositions were comprehensively compared. Firstly, the chemical characteristics, morphological characteristics and hydrophobicity relating to the adsorption capacity of electrospun PVDF/GO membranes were investigated through Fourier transform infrared spectroscopy, Raman spectroscopy, energy-dispersive X-ray spectroscopy, scanning electron microscopy and water contact angle measurement. Adsorption analysis showed that the adsorption performance of electrospun PVDF/ GO increased as GO contents increased. Variations in the average diameter of electrospun PVDF/GO fibres in the range of several micrometres did not cause a distinguishable change in their adsorption capacity. Electrospun PVDF/GO membranes without a porous structure inhibited a low adsorption capacity although they contained a high composition of GO. The modification of electrospun PVDF/GO membranes by adding PEG increased the distribution of GO on the surface of fibres, resulting in a more hydrophilic fibre surface and a notable increase in Pb2+ adsorption. The adsorption behaviour of Pb2+ onto electrospun PVDF/GO/PEG membranes was found to be dependent on contact time and pH. Reusability analysis indicated that the electrospun PVDF/GO/PEG membrane maintained a Pb2+ removal rate of over 80% after six adsorption-desorption cycles. Therefore, electrospun PVDF/GO/PEG membranes might be a promising adsorption material used in filtration systems for heavy metal removal.

베트남 학습자를 위한 직업 목적 한국어 교육과정의 교수요목 설계 방안 - 관광업 중심으로 - ·

La Thi Thanh Mai,Tran Hai Duong,Ngo Tran Viet Trinh 국제한국언어문화학회 2018 국제한국언어문화학회 학술대회 Vol.2018 No.05

Key Determinants for Users Intention to Use Smarthome Devices in Vietnam

Nguyen, Thi-Hong-Linh,Duong, Minh-Hung,Nguyen, Hai-Dang,Vo, Dang-HongNgan,Vu, Duy-Phuong-Trinh,Le, Hoanh-Su Korea Multimedia Society 2018 The journal of multimedia information system Vol.5 No.4

Smarthome is one of the remarkable fields of the industrial revolution 4.0, which are popular in many countries such USA, EURO, Japan and Korea. However, how Vietnamese people are considering and having intension to use smarthome devices is still a question for marketers and researchers. This study develops a comprehensive research model that can explain potential customers' behavioral intentions to adopt and use Smarthome services in Viet Nam and figure which key factors affect the intention. This study proposes and validates a new theoretical model that extends the Unified Theory of Acceptance and Use of Technology 2 (UTAUT2). The model consists of eight factors that affect one element (Behavioral Intention), specifically: Habits, Perceived usefulness, Perceived ease of use, Trust, Innovativeness Personal, Perceived value, Hedonic motivations and Social influences. Data were collected from 304 Vietnamese citizens by sending the email to survey questionnaire, direct contact with the experienced smarthome users. Through regression analysis, data from samples were analysed with SPSS 20 software and verification of hypotheses, the results show the key determinants affecting the intention to use smarthome appliances in Vietnam: Perceived Value, Social Influence, Perceived Usefulness, Perceived Ease of Use and Trust. From this result, several recommendations have been suggested to to smarthome devices vendors and marketer to improve products as well as marketing approaches to meet customer needs.

The Factors Affecting Intention to Use Smarthome Devices in Vietnam

Nguyen Thi-Hong-Linh,Duong Minh-Hung,Nguyen Hai-Dang,Vo Dang-HongNgan,Vu Duy-Phuong-Trinh,Le Hoanh-Su 한국경영정보학회 2018 한국경영정보학회 학술대회논문집 Vol.2018 No.5

Evaluation of potential probiotic and technological properties of lactic acid bacteria isolated from traditional fermented lap xuong sausage in northwestern Vietnam

Hoang Thi Lan Anh,Le Thi Thanh Hue,Bui Nguyen Hai Linh,Trinh Thanh Trung 한국미생물학회 2023 미생물학회지 Vol.59 No.2

Consumer demand for high-quality and safe fermented meat products is increasing recently, with great attention on functional starter cultures using lactic acid bacteria (LAB). This study aimed to select autochthonous LAB strains that have beneficial effects for human health and technological properties for the production of lap xuong, a traditional fermented sausage of ethnic minorities in northwestern Vietnam. From nine lap xuong samples, 63 LAB strains were isolated and identified into 14 species belonging to 8 genera. Latilactobacillus sakei was the most common species, followed by Lactiplantibacillus plantarum, Lactococcus lactis, and Pediococcus pentosaceus. Five strains of Enterococcus faecium LM0204, Lactococcus lactis LM0302, Latilactobacillus sakei LM0405, Lactiplantibacillus plantarum LM0705, and Lactiplantibacillus plantarum LM0901 exhibited probiotic properties, including tolerance to gastrointestinal tract conditions, adhesion ability to HT-29 cell line, antagonistic activity against harmful bacteria, and antioxidant activities. The strains were further evaluated for technological and safe properties, such as gas production, growth at different temperatures and simulated fermentation and ripening stages, lactic acid production, biogenic amine production, and antibiotic susceptibility. Enterococcus faecium LM0204 and Lactococcus lactis LM0302 were excluded because of tyramine production or unable growth in simulated fermentation conditions. All together probiotic properties and better technical functionality, Latilactobacillus sakei LM0405 and Lactiplantibacillus plantarum LM0705 were proposed as starter cultures for sausage production in northwestern Vietnam. Further studies are needed to standardize the sensory quality and safety aspects of lap xuong in this area using the proposed starter cultures strains for making fermented sausage.

Adlay Seed Extract (Coix lachryma-jobi L.) Decreased Adipocyte Differentiation and Increased Glucose Uptake in 3T3-L1 Cells

Do Thi Ha,Trinh Nam Trung,Nguyen Hai Nam,Chu Van Men,Nguyen Bich Thu,Tran Thi Phuong,KiHwan Bae 한국식품영양과학회 2010 Journal of medicinal food Vol.13 No.6

The aim of the present study was to investigate effects of the ethyl acetate fraction of an ethanol extract of Coix lachryma-jobi (ECLJ) on glucose uptake and adipocyte differentiation in 3T3-L1 cells. ECLJ phosphorylated AMP-activated protein kinase (AMPK) and its downstream substrate acetyl-coenzymeA carboxylase in 3T3-L1 cells in a time- and dosedependent manner. Moreover, we discovered that compound C inhibits ECLJ-stimulated ACC phosphorylation. In addition,ECLJ exhibited a dose-dependent stimulation of glucose uptake in 3T3-L1 cells, and this increase was obviously attenuated by compound C. ECLJ also caused a decrease in the expression levels of adipogenesis factors such as fatty acid synthase, sterolregulatory-element-binding protein-1c, peroxisome proliferator-activated receptor g, and CAATT=enhancer binding protein a in a dose-dependent manner. Differentiation was examined by Oil red O staining activity after ECLJ treatment for 6 days. ECLJ decreased mean droplet size. These results suggest a possible role for AMPK in the process of adipose differentiation and that ECLJ targeted for adipocyte functions could be effective in improving the symptoms of metabolic syndrome.

A Model-free Output Feedback Adaptive Optimal Fuzzy Controller for LC-filtered Three-phase Voltage Source Inverters

Nam Hai Trinh,Loc Ong Xuan,Nga Thi-Thuy Vu,Anh Tuan Nguyen 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.6

This paper proposes a model-free output feedback control-based adaptive fuzzy controller using a current-sensorless configuration for LC-filtered three-phase voltage source inverters (VSIs). The proposed adaptive fuzzy scheme is constructed of three parts: an adapter, an adaptive optimal fuzzy controller, and an adaptive optimal fuzzy identifier. The adapter is designed based on an adaptive neuro-fuzzy inference system (ANFIS) network which uses the error between the system output and identifier output as an input to generate the online updated parameters. Next, both the adaptive fuzzy controller and the fuzzy identifier are designed based on the Takagi-Sugeno (T-S) fuzzy model. In particular, the proposed algorithm is robust against external disturbance and parameter uncertainties due to not requiring the system parameters. Moreover, the proposed scheme uses a current-sensorless configuration, which reduces the system complexity and cost. Both the stability of the proposed method and the convergence of adapted parameters are completely assured by using the Lyapunov stability theory. Finally, the effectiveness of the proposed adaptive fuzzy controller is verified through simulation in comparison with a conventional T-S fuzzy controller. The results show that the proposed model-free output feedback control-based adaptive fuzzy controller yields better control performance, such as faster transient response, smaller steady-state error, and lower total harmonic distortion (THD) under the change of load (step changes of linear load, unbalanced load, and nonlinear load), parameter variations, and input disturbances.

Determinants Influencing Consumers Purchasing Intention for Sustainable Fashion: Evidence from Ho Chi Minh City

Thuy Thi Hai HO,Trinh Ngoc Phuong VU,Hieu Minh VU 한국유통과학회 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.11

This paper investigates factors impacting on sustainable fashion buying intention of consumers by reviewing studies about the topic and conducting a survey with consumers in Ho Chi Minh City. In detail, firstly, an interview with 15 respondents was conducted to check the understanding of concepts and questions and, secondly, the study used the convenient sampling method, with 172 samples collected and analyzed, of which young respondents accounted for the majority of the sample. The respondents tend to go shopping many times in a year, with the number of people buying fashion products from every week to every two months accounting for 65.2% totally. The findings suggest that the firms should prioritize strategies that can improve customer attitude toward sustainable fashion, making them feel good, pleasant, satisfied and favorable when engaging in sustainable fashion consumption. This study concludes that consumers need more information to enable them to make better ethical decisions. This study proposes that the major channels that consumers use to seek sustainable product information include public education, peer influence, and corporate marketing information about the products. This study concludes that public education and corporate marketing information on green consumption education is effective for improving consumer sustainable buying intention.

Effect of post-synthesis annealing on properties of SnS nanospheres and its solar cell performance

트롱윈탐윈,Ha Hai Thi Hoang,Thanh Kieu Trinh,Viet Thanh Hau Pham,Ryan Patrick Smith,박진호 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.4

SnS nanospheres (NSPs) were synthesized, and the effects of thermal annealing on the structural, morphological, chemical compositional and optical properties were examined. As-synthesized SnS NPSs with a mean size of 3- 4 nm underwent a solid state morphological transformation by high temperature annealing in a nitrogen environment. Upon annealing, the size of SnS NSP increased to 5-6 nm with enhanced crystallinity. Also, the photoluminescence (PL) of the nitrogen-annealed samples slightly decreased in intensity with accompanying red-shift in spectrum. The power conversion efficiency of the solar cells using a polymer and the SnS NSPs was ~0.71%. These results confirm that the SnS NSPs demonstrate a potential as an inorganic material to be used in organic-inorganic hybrid bulk heterojunction (BHJ) photovoltaic devices.

Self-antibacterial chitosan/Aloe barbadensis Miller hydrogels releasing nitrite for biomedical applications

Thai Thanh Hoang Thi,Binh D.T. Trinh,Phuong Le Thi,Dieu Linh Tran,박기동,Dai Hai Nguyen 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.103 No.-

Because of the toxic glutaraldehyde, the chitosan-glutaraldehyde hydrogels are seriously limited inbiomedical applications. In this study, exploiting bioactive compounds of Aloe barbadensis Miller, the chitosan/Aloe barbadensis Miller-glutaraldehyde (CS/AV-GDA) hydrogels were fabricated with 4-fold lowerglutaraldehyde concentration without compromising hydrogel characteristics. The gelation time wascontrolled from a few seconds to several hours. The elastic modulus was varied from 483 to 99940 Pa. The CS/AV-GDA hydrogels could release the natural nitrite amount from 24.0 to 89.6 lM within the firsthour for antibacterial activity, then continuously deliver a few lM every next hour for cell activities. Theantibacterial test against Escherichia coli and Staphylococcus aureus revealed that the CS/AV-GDA hydrogelscould kill the planktonic bacteria 5-fold more highly than control and prevent bacteria attachmenton hydrogel surface effectively. Although the CS/AV-GDA hydrogels consumed only 0.25% glutaraldehydeconcentration, their antibacterial capacities were comparable to chitosan-only hydrogels with 2% glutaraldehyde. For cytotoxicity tests, the CS/AV-GDA hydrogels using 0.25% glutaraldehyde concentrationinduce the human dermal fibroblasts proliferation significantly. All CS/AV-GDA hydrogels with glutaraldehydecrosslinker less than 1% showed non-cytotoxicity. As a result, the new CS/AV-GDA hydrogelsmight become an attractive candidate for medicine regeneration and tissue engineering.