Factors Affecting Enterprise's Satisfaction toward Social Security's Online Public Service: The Case of Thanh Hoa Province, Vietnam

NGO, Chi Thanh,NGUYEN, Thi Ngoc Mai,NGUYEN, Duy Dat,LE, Hoang Ba Huyen,LE, Van Cuong,LE, Thi Binh Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.9

The study aims to investigate factors affecting enterprise's satisfaction and loyalty toward the Social Security's online public services, looking at the case of Thanh Hoa province, Vietnam. This study employs samples with 216 enterprises that use online public system of Thanh Hoa province's Social Security. The research model is closely linked to the SERVQUAL model developed by Parasuraman, Zeithaml and Berry (1988). We propose 23 scales that constitute the quality of service, three scales that constitute Customer Satisfaction and three components that constitute Customer Loyalty. This study use the tool of Exploratory Factor Analysis (EFA), Cronbach's Alpha test, Confirm Factor Analysis (CFA) and Structural Equation Modeling (SEM) in order to address the question of satisfaction and loyalty. The result shows that the factor with the most impact is Reliability, next is Capacity of staffs, Tangibles, Attitude of staffs, and the least impacting factor is Empathy; moreover, the results also show that Satisfaction has a strong impact on Customer Loyalty. The findings of this study suggest that Thanh Hoa province's Social Security should: (i) strengthen the reliability of online service system; (ii) build capacity for staffs; (iii) develop the responsiveness of electronic transactions systems; and (iv) improve the empathy of staffs.

Factors that Affect Customers Satisfaction: An Empirical Study of Export-Import Service Consultant Companies in Vietnam

LE, Thai Thanh Dat,HO, Thi Thanh Ngan,LE, Nguyen Truc Quyen,HUYNH, Thi Khanh Tuyen,NGUYEN, Minh Tri,LUU, Thi Mai Anh,HOANG, Thi Phuong Thao,NGUYEN, Trong Luan Korea Distribution Science Association 2022 The Journal of Asian Finance, Economics and Busine Vol.9 No.6

The purpose of the study is to analyze the significant impacts of expectations, performance, complaints, and fairness that affect consumer satisfaction. The methodology involves reviewing and referencing relevant literature carefully, then proposing a model for customer satisfaction. This study is empirically based on a survey with 50 respondents who work in the field of import and export in the region stretching from the north to the south of Vietnam. The sampling method used in this study is the in-depth interview method. The results show that: (1) expectation has a specific impact on customer satisfaction, (2) performance has a positive impact on customer satisfaction, and (3) complaint which is an intermediary factor between expectation, performance, and fairness has an impact on satisfaction, (4) fairness has a positive effect on satisfaction, in addition, fairness is an extremely important feature when customers choose an import-export service. Research implies that increasing expectations, performance, and fairness results in an improved customer experience and satisfaction when they use the service. It is suggested that the complaint factor continue to be studied and looked into because it still has some effect on satisfaction and is an intermediate variable that changes how the other factors relate to each other.

Composites derived from synthetic clay and carbon sphere: Preparation, characterization, and application for dye decontamination

Nguyen Duy Dat,Ton That Loc,Mai Thuan Trieu,Dong Thanh Nguyen,Khuong Quoc Nguyen,My Linh Nguyen,Anh Duy Duong Le,Hai Nguyen Tran 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.4

Two new composites from synthetic clay-like materials and carbon spheres were developed. Layered doubledhydroxides (LDH) were synthesized from the coprecipitation of Mg2+ and Al3+ ions. Spherical hydrochar (SH) wasprepared from pure glucose through hydrothermal carbonization at 190 oC. The composite LDH–SH was synthesizedthrough a simple hydrothermal method of the mixture of LDH and SH. Another composite, LDO-SB, was directly preparedthrough the carbonization of LDH-SH at 500 oC. Under such high temperature, LDH was converted to layereddoubled oxides (LDO), and SH was transferred to spherical biochar (SB). Those materials were characterized by chemicalstability, surface morphology and element composition, crystal structure, surface functional group, and texturalcharacteristic. They were applied for removing cationic dye (methylene blue; MB) and anionic dye (Congo red; CR)under different pH solutions. Three adsorption components—kinetics, isotherm, and thermodynamics—were conductedunder batch experimenters. Results demonstrated that the LDH or LDO particles were assembled on the surfaceof SH or SB, respectively. The surface area, total pore volume, and average pore width of LDH–SH and LDO-SBwere 58.5 and 198m2/g, 0.319 and 0.440 cm3/g, and 21.8 and 8.89 nm, respectively. The maximum adsorption capacityof the materials, calculated from the Langmuir model, at 30 oC for CR and MB dyes was 1589 and 78.6mg/g (LDOSB)and 499 and 226mg/g (LDH-SH), respectively. The composites exhibited a higher affinity to anionic than cationicdyes, which resulted from the great contribution of the clay-like materials. Therefore, they can serve as a promisingcomposite for the decolorization of wastewater.

The promoter of tomato HISTIDINE DECARBOXYLASE A is fruit-specific, and its expression is stably maintained in fruits during ripening

김아영,김현민,마상훈,박서영,MAI THANH DAT,장규필,정영희 한국식물생명공학회 2019 Plant biotechnology reports Vol.13 No.1

Identifying novel promoters with specific temporal and spatial expression patterns is crucial for crop biotechnology. In this study, we isolated a fruit-specific promoter in tomato, HISTIDINE DECARBOXYLASE A (SlHDC-A) promoter. Through RNA-seq and RT-PCR analysis, we found that SlHDC-A was predominantly expressed in fruits and that its expression was stable in fruits during ripening. These results suggest that the promoter of SlHDC-A might have the ability to determine fruit-specific gene expression. To test this possibility, we generated transgenic tomato transformed with SlHDC-A::GUS and 35S::GUS. Unlike 35S::GUS transgenic tomato with constitutive expression in various tissues, SlHDC-A::GUS transgenic plants showed fruit-specific expression of GUS. The intensity of GUS activity in fruits of SlHDC-A::GUS transgenic plants was approximately tenfold higher than that in fruits of 35S::GUS transgenic plants. The core region responsible for its fruit-specific expression was identified by promoter deletion analyses. Removal of the − 880 to − 577 region abolished the fruit-specific expression of SlHDC-A promoter. This suggests that the − 880 to − 577 region is the core region responsible for the fruit-specific expression of SlHDC-A. This finding was further supported by analysis of chimeric fusion promoter. Unlike 35S minimal promoter which had no activity to express GUS, the chimeric fusion promoter of the core region and 35S minimal promoter showed fruit-specific expression similar to intact SlHDC-A promoter. Collectively, these findings indicate that the promoter of SlHDC-A is fruit-specific and the − 880 to − 577 region is the core region of SlHDC-A promoter.

Facile synthesis of MoS2 nanosheets-carbon nanofibers composite as catalysts for hydrogen evolution reaction

Nguyen Thi Minh Nguyet,Le Van Thang,Nguyen Huu HuyPhuc,Vinh-Dat Vuong,Tran Van Khai,Mai Thanh Phong 한양대학교 세라믹연구소 2019 Journal of Ceramic Processing Research Vol.20 No.2

MoS2 nanosheets (NS) were directly grown on carbon nanofiber (CF) and employed as electrocatalyst for hydrogen evolutionreaction (HER). The structural, surface morphology and chemical composition of the nanocomposites were characterized byfield emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), energydispersiveX-ray spectroscopy (EDS), X-ray diffraction (XRD), and Raman spectroscopy. XRD and TEM-EDS measurementsshowed that the molybdenum oxide precursor was successfully transferred into MoS2 nanosheets. It was confirmed from FESEMand TEM images that NS was uniformly distribution on surface of the CF. The HR-TEM images disclosed that the NSwas formed perpendicular to surface of CF fibers via the MoS2 layers growth parallel to CF surface which act as interface. The HER current density was about 12 mA cm−2 at catalyst loading of only 60 μg cm−2 at -0.384 V (vs. RHE).

Heterologous expression in E. coli and functional characterization of the tomato CPR enzymes

Choi Won,Park Seo Young,Kim Hyun Min,Mai Thanh Dat,Do Ju Hui,Jang Hye Min,Hwang Hyeon Bae,Song Eun Gyeong,Shim Jae Sung,Joung Young Hee 한국응용생명화학회 2023 Applied Biological Chemistry (Appl Biol Chem) Vol.66 No.-

NADPH-cytochrome P450 reductase (CPR) is a key enzyme transferring electrons to cytochrome P450. In tomatoes (Solanum lycopersicum), two CPR genes, SlCPR1 and SlCPR2, were identified. In all the tested tomato tissues, SlCPR2 showed higher expression levels than SlCPR1. SlCPR2 expression increased significantly with jasmonic acid treatment. No significant changes were observed with salicylic acid or drought stress treatment. The cDNA of SlCPRs were expressed in Escherichia coli without any amino acid modification. And the heterologously expressed SlCPR enzymes were reacted with several protein and chemical substrates. SlCPR2 was more active than SlCPR1. Both SlCPR1 and SlCPR2 exhibited strong activity across a pH range of 6.0 to 9.0, with peak activity at pH 8.0. The study opens possibilities for CPR control, biocatalyst development, and exploring oxidase enzyme functions.

Effect of hydrothermal time on the structure and property of graphene oxide membrane

Tran Van Khai,Pham Thuy Trang,Le Ngoc Long,Le Van Thang,Tran Duc Chau,Vuong Vinh Dat,Mai Thanh Phong 한양대학교 세라믹연구소 2021 Journal of Ceramic Processing Research Vol.22 No.4

Two dimensional graphene oxide (GO) has potential application in membrane separation owing to its unique structure andphysicochemical properties. In this study, the reduced graphene oxide (rGO) was synthesized from GO via hydrothermaltreatment at 160 oC for 1, 2, 3 and 4 h, and the rGO membranes were prepared on cellulose nitrate supporting membranesby vacuum filtration. The structural change and chemical composition of GO were investigated using X-ray diffraction (XRD),Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM),atomic force microscopy (AFM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS) andcontact angle measurements. The result shows that uniformly intact rGO membranes with good hydrophobicity could beachieved by adjusting the reduction degree of GO through changing the hydrothermal reaction time. The huge improvementof the hydrophobic property of rGO could be attributed to the removal of the most the hydrophilic oxygen-containingfunctional groups on the surface of GO. Additionally, the structure, chemical composition, and d-spacing of the GO can alsobe controlled by adjusting the reduction time. This method holds great potential because it can be prepared in large quantitiesat low cost, and suitable for applications in membrane technologies.