Research o n the Role o f the Attitud es o f Vietnamese C onsumers Towards their Intentions to Use Mobile Money

Thuy Hang Vu Thi(Thuy Hang Vu Thi ) People & Global Business Association 2024 Global Business and Finance Review Vol.29 No.2

Logistics Service Quality, Customer Satisfaction, and Loyalty During the COVID-19 Pandemic in Vietnam

Xuan Hung NGUYEN(Xuan Hung NGUYEN ),Thuy Dương TRAN(Thuy Dương TRAN ),Phan Hoai Diem VU(Phan Hoai Diem VU ),Yen Chi DINH(Yen Chi DINH ),Thi Mai Huong DUONG(Thi Mai Huong DUONG ),Thi Ngoc Hien THAN(Thi 한국유통과학회 2022 The Journal of Asian Finance, Economics and Busine Vol.9 No.9

The goal of the study is to examine and assess how the factors of logistics service quality provided by logistics service providers influence customer loyalty and satisfaction in Vietnam. This study employs samples of the Kansei technique. The article’s data was gathered through an online survey of 388 distinct Vietnamese customers who used logistics services before and during the Covid-19 outbreak. After the data was obtained, it was evaluated using SmartPLS 3.0’s Cronbach’s Alpha test and structural equation model (SEM). Staff service quality, operational service quality, and technical service quality are the three factors that determine the quality of logistics services in the study. Out of the 10 proposed hypotheses, research findings show that five are acceptable. The Covid-19 Pandemic in Vietnam had a significant impact on all dimensions, but it had no effect on how satisfied customers were with the logistics service providers. Nevertheless, loyalty is considerably influenced by only one factor, which is customer satisfaction, and customer trust moderates the relationship between these two factors. As a consequence of that, several managerial implications have been proposed to help logistics service providers improve their services to attract and keep Vietnamese customers using their service in the long term.

Direct synthesis of hydrogen peroxide over palladium catalysts supported on glucose-derived amorphous carbons

Hang Thi Thuy Vu,Viet Le Nam Vo,정영민 한국화학공학회 2021 Korean Journal of Chemical Engineering Vol.38 No.6

Untreated and sulfonated biomass-derived amorphous carbons were prepared by the pyrolysis of D-glucose at different temperatures, followed by sulfonation. Not only the surface functional group concentration but also the structure of polyaromatic carbon sheets was significantly affected by the carbonization temperature and sulfonation. More importantly, the carbonization temperature played a crucial role in determining the size of Pd nanoparticles (NPs) on glucose-derived carbons (GCx) and thereby affected the catalytic performance of Pd/GCx for the direct synthesis of hydrogen peroxide (DSHP). The volcano-shaped dependency between the Pd NP size and the carbonization temperature of GCx agrees well with the reverse relationship between the Pd NP size and the catalytic activity of Pd/ GCx. The flexible polyaromatic carbon sheet structure of the GCx was beneficial in increasing the sulfonic acid group content on the carbon surface and, therefore, H2O2 selectivity was improved in the presence of the Pd/S-GC2 catalyst (Pd supported on the sulfonated glucose-derived carbon pyrolyzed at 723 K). However, both H2 conversion and H2O2 productivity decreased over the same catalyst, possibly due to the decreased number of active sites on the clustered or single-site Pd. Reducing the catalyst resulted in a decrease in H2O2 selectivity by significantly lowering the Pd2+/Pd0 ratio and increasing the Pd NP size. These results clearly demonstrate that fine control of the physicochemical properties of the active metal and GCx support and their synergistic combination is essential to realize an efficient Pd catalyst supported on GCx for the DSHP reaction.

SCN1A Gene Mutation and Adaptive Functioning in 18 Vietnamese Children with Dravet Syndrome

Thi Thu Hang Do,Diem My Vu,Thi Thuy Kieu Huynh,Thi Khanh Van Le,손은화,Thieu Mai Thao Le,Huu Hao Ha,Chi Bao Bui 대한신경과학회 2017 Journal of Clinical Neurology Vol.13 No.1

Background and Purpose Dravet syndrome is a rare and severe type of epilepsy in infants. The heterogeneity in the overall intellectual disability that these patients suffer from has been attributed to differences in genetic background and epilepsy severity. Methods Eighteen Vietnamese children diagnosed with Dravet syndrome were included in this study. SCN1A variants were screened by direct sequencing and multiplex ligation-dependent probe amplification. Adaptive functioning was assessed in all patients using the Vietnamese version of the Vineland Adaptive Behavior Scales, and the results were analyzed relative to the SCN1A variants and epilepsy severity. Results We identified 13 pathogenic or likely pathogenic variants, including 6 that have not been reported previously. We found no correlations between the presence or type of SCN1A variants and the level of adaptive functioning impairment or severity of epilepsy. Only two of nine patients aged at least 5 years had an adaptive functioning score higher than 50. Both of these patients had a low frequency of convulsive seizures and no history of status epilepticus or prolonged seizures. The remaining seven had very low adaptive functioning scores (39 or less) despite the variability in the severity of their epilepsy confirming the involvement of factors other than the severity of epilepsy in determining the developmental outcome. Conclusions Our study expands the spectrum of known SCN1A variants and confirms the current understanding of the role of the genetic background and epilepsy severity in determining the developmental outcome of Dravet syndrome patients.

Direct synthesis of H2O2 over Pd/C catalysts prepared by the incipient wetness impregnation method: Effect of heat treatment on catalytic activity

Vu Thi Thuy Hang,정영민 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.1

Although various Pd/C catalysts have been applied in the direct synthesis of H2O2, unsatisfactory H2O2 yields have been achieved. We systematically investigated the effect of heat treatment on the physicochemical properties of Pd/C catalyst, and thereby on the catalytic performance in the direct synthesis of H2O2. Pd/C catalysts prepared by the incipient wetness method were subjected to different heat treatments and applied in H2O2 synthesis. The calcination temperature was found to have a key role in determining the Pd nanoparticle (NP) size; calcination at 523 K yielded highly oxidized and small Pd NPs corresponding to the sub-nano domain (1.4-2.5 nm). This Pd/C catalyst is superior not only in promoting H2O2 formation, but also in suppressing the subsequent unfavorable H2O2 decomposition and hydrogenation, which explains its excellent H2O2 productivity (as high as 4,443mmol H2O2/g Pd·h) and selectivity (94.5%). On the other hand, the reaction performance of the Pd/C catalysts calcined at a higher temperature (673 K) or reduced under hydrogen was sharply reduced owing to the formation of larger Pd NPs or the enhancement of the metallic nature of Pd, respectively. The amount of residual Cl ion on Pd/C catalyst after heat treatment also had an impact on the catalytic activity as it affected the pH of reaction solution. These results clearly demonstrate that an efficient Pd/C catalyst can be realized by fine tuning the conditions of heat treatment during catalyst preparation.

Critical Factors Affecting the Innovation Activities of Businesses: Evidence from Binh Dinh Province, Vietnam

NGUYEN, Thi Le Hang,PHAM, Ngoc Toan,DAO, Vu Phuong Linh,NGO, Thi Thanh Thuy,LE, Thi Thanh Binh Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.7

The study investigates the factors influencing the innovation activities in the enterprises in the Binh Dinh Province, Vietnam. By employing the dataset from a survey in 200 typical enterprises in Binh Dinh and using the Exploratory Factor Analysis and regression analysis, we found that there are eight factor groups affecting the innovation activities of enterprises. They include management of innovation promotion; market research capacity; leadership inspiring innovation; culture of innovation; human resources for implementing innovation; network connection; disseminating/sharing knowledge; and impact of producing/serving technology. All these factors strongly affect the innovation activities, which plays an important role in promoting the sustainable development of the Vietnamese enterprises, with the statistical significance level at 1%. Moreover, findings also show that, among these factors, the market research capacity is the strongest determinant of the innovation activity in the enterprise. An increase of 1 point of capacity of market research will increase the innovation activities in the enterprise by 0.114 point. It is followed by the management of promoting innovation, leadership inspiring innovation, and disseminating and sharing knowledge, with 0.104, 0.103 and 0.102 score, respectively. On the other hand, network connection is the weakest factor, with the score of 0.07 point.

High-performance nonenzymatic electrochemical glucose biosensor based on AgNP-decorated MoS2 microflowers

Dinh Van Tuan,Dang Thi Thuy Ngan,Dao Vu Phuong Thao,Nguyen Thi Nguyet,Nguyen Thi Thuy,Nguyen Phuong Thuy,Vu Van Thu,Vuong-Pham Hung,Phuong Dinh Tam 한국물리학회 2022 Current Applied Physics Vol.43 No.-

A facile hydrothermal route was used to synthesize silver nanoparticle (AgNP)-decorated microflower molybdenum disulfide (MoS2-MF) for bio-electrochemical platform fabrication to detect nonenzymatic glucose concentration. The morphologies of the materials were studied by scanning electron microscopy, and their structural characteristics were analyzed by X-ray diffractometry and energy-dispersive X-ray spectroscopy. The electrochemical characteristics of the AgNPs/MoS2-MF/PtE biosensor were studied by cyclic voltammetry. The obtained data indicated that the developed nonenzymatic glucose sensor has a large linear response between 1.0 and 15.0 mM, a limit of detection of as low as 1.0 mM, and a sensitivity of 46.5 μA nM-1 cm-2. The biosensor also displayed outstanding selectivity, stability, reproducibility, and repeatability. Additionally, the AgNPs/MoS2-MF/ PtE biosensor was utilized to detect glucose concentration in real sample and showed practical application potential for glucose detection.

Synthesis and Characterization of Hydrotalcite/Graphene Oxide Containing Benzoate for Corrosion Protection of Carbon Steel

( Thuy Duong Nguyen ),( Boi An Tran ),( Ke Oanh Vu ),( Anh Son Nguyen ),( Anh Truc Trinh ),( Gia Vu Pham ),( Thi Xuan Hang To ),( Thanh Thao Phan ) 한국부식방식학회(구 한국부식학회) 2020 Corrosion Science and Technology Vol.19 No.2

This work examined the corrosion protection performance of benzoate loaded hydrotalcite/graphene oxide (HT/GO-BZ) for carbon steel. HT/GO-BZ was fabricated by the co-precipitation method and characterized by infrared spectroscopy, X-ray diffraction, and scanning electronic microscopy. The corrosion inhibition action of HT/GO-BZ on carbon steel in 0.1 M NaCl solution was evaluated by electrochemical measurements. The benzoate content in HT/GO-BZ was determined by UV-Vis spectroscopy. Subsequently, the effect of HT/GO-BZ on the corrosion resistance of the water-based epoxy coating was investigated by the salt spray test. The obtained results demonstrated the intercalation of benzoate and GO in the hydrotalcite structure. The benzoate content in HT/GO-BZ was about 16%. The polarization curves of the carbon steel electrode revealed anodic corrosion inhibition activity of HT/GO-BZ and the inhibition efficiency was about 95.2% at a concentration of 3g/L. The GO present in HT/GO-BZ enhanced the inhibition effect of HT-BZ. The presence of HT/GO-BZ improved the corrosion resistance of the waterborne epoxy coating.

The Influence of Hydrotalcite Intercalated with Benzoate on UV Stability of Acrylic Coating

Thuy Duong Nguyen,Anh Son Nguyen,Thu Thuy Thai,Gia Vu Pham,Thi Xuan Hang To,Marie-Georges Olivier 한국부식방식학회 2020 Corrosion Science and Technology Vol.19 No.1

It is important to realize that benzoate was intercalated into hydrotalcite (HTC-Bz) by the co-precipitationmethod. In this case, acrylic coating with 0.5 wt% HTC-Bz was deposited on carbon steel using the spincoating method. Next, the HTC-Bz structure was characterized by Field emission scanning electron microscopy(FESEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). In fact, an ultravioletvision spectroscopy (UV-Vis) was used to determine the benzoate content in HTC-Bz, and the UV absorptionability of HTC-Bz. Using electrochemical techniques, water contact angle measurement, and thermal-gravimetricanalysis, we compared the protective properties before and after QUV test, hydrophobicity and the thermalstability of acrylic coating containing HTC-Bz. The obtained results showed that HTC-Bz with a plate-likestructure was successfully synthesized; benzoate was intercalated into the interlayer of hydrotalcite witha concentration of 28 wt%. Additionally, it was noted that HTC-Bz has an UV absorption peak at 225nm. In conclusion, the addition of HTC-Bz enhanced the UV stability, hydrophobicity and the thermal stabilityof acrylic coating.

Effect of Zn/Al Cation Ratio on Corrosion Inhibition Capabilities of Hydrotalcites Containing Benzoate Against Carbon Steel

Thuy Duong Nguyen,To Thi Xuan Hang,Thu Thuy Pham,Anh Son Nguyen,Thu Thuy Thai,Gia Vu Pham,Ngoc Bach Ta 한국부식방식학회 2022 Corrosion Science and Technology Vol.21 No.6

Corrosion inhibitors based on Zn-Al hydrotalcites containing benzoate (ZnAlHB) with different molar ratios of Zn/Al were prepared with a co-precipitation process. Compositions and structures of the resulting hydrotalcites were studied with suitable spectroscopic methods such as inductively coupled plasma mass spectrometry (ICP-MS), ultraviolet-visible spectrophotometry (UV-Vis), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and surface zeta potential measurements, respectively. Results of physico-chemical studies showed that crystallite sizes, compositions of products, and surface electrical properties were significantly changed when the molar ratio of Zn/Al was increased. The release of benzoate from hydrotalcites also differed slightly among samples. Anticorrosion abilities of hydrotalcites intercalated with benzoate at a concentration of 3 g/L on carbon steel were analyzed using electrochemical impedance spectroscopy (EIS), polarization curve, energy-dispersive X-ray spectroscopy (EDX), and SEM. Corrosion inhibition abilities of benzoate modified hydrotalcites in 0.1 M NaCl showed an upward trend with increasing Zn/Al ratio. The reason for the dependence of corrosion resistance on the Zn/Al ratio was discussed, including changes in the microstructure of hydrotalcites such as crystal size, density, uniformity, and formation of ZnO.