Search
Author
- Anh-Tuan Le (14)
- Quan-Hoang Vuong (14)
- Ngo, Xuan Dinh (11)
- Tuan Q. Do (10)
- next >
Subject
- Electrospinning (7)
- Nanoparticles (6)
- Machine learning (5)
- Compound droplet (4)
- next >
Date issued
Has File(s)
Search Results
In this study, we present the fabrication of nitrile butadiene rubber/waste leather fiber (NBR/WLF) composites with different weight percentages of WLF and NBR (0/100, 20/80, 30/70, 40/60, 50/50, 60/40 wt/wt). WLF was prepared by cutting the scrap leathers from the waste product of the Vietnamese leather industry. Subsequently, in order to make the short fibers, it was mixed by a hammer mill. The characteristics of WLF/NBR composites such as mechanical properties (tensile strength, tear strength, hardness), dynamic mechanical properties, toluene absorption, and morphology were carefully evaluated. As a result, the tensile strength and tear strength become larger with increasing WLF content from 0 to 50 wt% and they decrease when further increasing WLF content. The highest tensile st... |
Economic research is vital for creating more suitable policies to facilitate economic growth. Employing a combination of descriptive and Bayesian analyses, this paper investigates the research landscape of the economics discipline in Vietnam, in particular, the leading affiliations in the field and how these institutions compare to each other in terms of productivity, the number of lead authors, new authors and publications' journal impact factor. We also examine the differences in the authors' productivity based on their age and gender. The dataset extracted from the SSHPA database includes 1,444 articles. The findings show that among top producers of economic research in Vietnam, seven are universities, leaving only one representative of research institutes. These top producers ac... |
It is shown for the first time that the deep eutectic solvent, DES, formed by acetylcholine chloride and urea can be successfully used for Ag recovery from the cathode powder of spent silver oxide batteries. This DES performs two important functions namely, as selective leaching liquor to extract Ag(I) ions from the remaining Ag2O, leaving intact the metallic Ag in the solid phase, and as electrolytic bath for silver electrodeposition onto a glassy carbon electrode or graphite. Using potentiodynamic and potentiostatic electrochemical measurements, it was possible to quantify both: the Ag(I) leaching rate and the concentration of Ag(I) ions leached after 24 h. From this value, it was possible to estimate that about 7% of the original mass of the cathode powder corresponds to Ag2O and... |
Although Vietnam has been successful in the fight against the first wave of COVID-19, domestic outbreaks have continued to occur. Given university students constitute a significant proportion of the population in Vietnam, to improve the prevention and control of COVID-19 in Vietnam and comparable countries, we examined their knowledge, attitude, and practice (KAP) towards face mask use which is an important preventive measure and the association between the levels of COVID-19 knowledge and KAP towards face mask use. A cross-sectional survey was conducted on all students studying at Phenikaa University, Hanoi, using a self-developed questionnaire consisted of 42 questions regarding KAP towards face mask use as well as reuse of cloth mask, and COVID-19 knowledge. Among 728 participant... |
In this study, the synthesis of micro-wheels composed of self-assembled tungsten oxide nanorods supported platinum (WO3/Pt) by atmospheric plasma reduction and its application in a counter electrode (CE) for highly efficient dye-sensitized solar cells were discussed. To characterize the developed materials, we conducted SEM, TEM, EDS-TEM, XRD. Due to a large surface-active area of developed material and its support for Pt nanoparticles in diameters of 2–3 nm, the WO3/Pt electrode indicated as a greater electrochemical catalyst for the redox reaction than Pt and WO3 CEs. Thus, the power conversion efficiency for a device with WO3/Pt electrode is improved to 8.10%, compared to 4.36% for a device with WO3 electrode and 7.61% for a cell with a Pt electrode. This study also supplies a pr... |
It is a challenge to harvest both electricity and freshwater from the oceans. This communication demonstrates that the natural-inspired hierarchical evaporator based on multi-walled carbon nanotubes can generate electricity via water evaporation for freshwater production. Furthermore, for the first time, the effect of the nature of exposed electrodes in an electrolyte solution and the distance between two electrodes on the generation of electricity is carefully investigated. We found that the natural-inspired hierarchical evaporator could generate electricity for all time of the day. The proposed natural-inspired hierarchical evaporator is scalable, feasible, and low-cost, providing great potential for direct industrial applications of solar energy on clean water and electricity gen... |
In this paper, a nondestructive inspection system is proposed to detect and quantitatively evaluate the size of the near- and far-side damages on the tube, membrane, and weld of the water-cooled wall in the fluidized bed boiler. The shape and size of the surface damages can be evaluated from the magnetic flux density distribution measured by the magnetic sensor array on one side from the center of the magnetizer. The magnetic sensors were arrayed on a curved shape probe according to the tube’s cross-sectional shape, membrane, and weld. On the other hand, the couplant was doped to the water-cooled wall, and a thin film was formed thereon by polyethylene terephthalate. Then, the measured signal of the flexible ultrasonic probe was used to detect and evaluate the depth of the damages. ... |
Recently, auxetic cellular solids in the forms of honeycombs and carbon nanotube reinforced composite (CNTRC) have great potential in a diverse range of applications. This paper studies the nonlinear free and forced vibration of sandwich cylindrical panel on visco-Pasternak foundations in thermal environment subjected to blast load The sandwich cylindrical panel consists of auxetic honeycombs core layer and two CNTRC face sheets. The Poisson’ ratio of the auxetic core is negative and the material properties of CNTRC face sheets are assumed to continuously vary in the thickness direction according to four different types of linear functions. The blast load is determined from the distance of the center of blast to center of the structure and the mass of explosive materials. The fundam... |
Ginseng has been well-known as a medicinal plant for thousands of years. Bacterial endophytes ubiquitously colonize the inside tissues of ginseng without any disease symptoms. The identification of bacterial endophytes is conducted through either the internal transcribed spacer region combined with ribosomal sequences or metagenomics. Bacterial endophyte communities differ in their diversity and composition profile, depending on the geographical location, cultivation condition, and tissue, age, and species of ginseng. Bacterial endophytes have a significant effect on the growth of ginseng through indole-3-acetic acid (IAA) and siderophore production, phosphate solubilization, and nitrogen fixation. Moreover, bacterial endophytes can protect ginseng by acting as biocontrol agents. In... |
The selective detection and classification of NH3 and H2S gases with H2S gas interference based on conventional SnO2 thin film sensors is still the main problem. In this work, three layers of SnO2/Pt/WO3 nanofilms with different WO3 thicknesses (50, 80, 140, and 260 nm) were fabricated using the sputtering technique. The WO3 top layer were used as a gas filter to further improve the selectivity of sensors. The effect of WO3 thickness on the (NH3, H2, and H2S) gas-sensing properties of the sensors was investigated. At the optimal WO3 thickness of 140 nm, the gas responses of SnO2/Pt/WO3 sensors toward NH3 and H2 gases were slightly lower than those of Pt/SnO2 sensor film, and the gas response of SnO2/Pt/WO3 sensor films to H2S gas was almost negligible. The calcification of NH3 and H... |
