Effects of Mg Al Alloy Powder on the Combustion and Infrared Emission Characteristics of the Mg Al PTFE Viton Composition

Metal-Fluorocarbon compositions are the pyrotechnic formulations which have been widely used in infrared decoy flares to protect aerial targets from infrared guide missile seekers. In this work, the effect of Mg-Al alloy powder (i.e. the particle size and the content) on the combustion and the infrared emission characteristics (i.e. the infrared emission distribution and the infrared radiance) of the pyrotechnic composition based on Mg-Al alloy, polytetrafluoroethylene (PTFE) and Viton rubber are described. The results show that the high burning rate (with the values of 4.0 mm.s-1 to 10.0 mm.s-1, depend on the compression density) of this composition is achieved with a high content of Mg-Al alloy or when using fine Mg-Al alloy particles as well as coarse PTFE particles. On the other hand, the infrared emission radiance (in the wavelength range of 2.5 μm to 5.0 μm) of Mg-Al/PTFE/Viton composition reaches maximum values (i.e. 17.7 W.cm-2.Sr-1 and 21.0 W.cm-2.Sr-1 with the size of Mg-Al particles are 20 μm and 120 μm, respectively) at 60 wt% Mg-Al alloy. Finally, the Mg-Al/PTFE/Viton composition has a similar combustion and emission characteristics as the Mg/PTFE/Viton composition

How scientific research changes the Vietnamese higher education landscape: Evidence from social sciences and humanities between 2008 and 2019

Background: In the context of globalization, Vietnamese universities, whose primary function is teaching, there is a need to improve research performance. Methods: Based on SSHPA data, an exclusive database of Vietnamese social sciences and humanities researchers’ productivity, between 2008 and 2019 period, this study analyzes the research output of Vietnamese universities in the field of social sciences and humanities. Results: Vietnamese universities have been steadily producing a high volume of publications in the 2008-2019 period, with a peak of 598 articles in 2019. Moreover, many private universities and institutions are also joining the publication race, pushing competitiveness in the country. Conclusions: Solutions to improve both quantity and quality of Vietnamese universities’ research practice in the context of the industrial revolution 4.0 could be applying international criteria in Vietnamese higher education, developing scientific and critical thinking for general and STEM education, and promoting science communication

Application of chitosan solutions for rice production in Vietnam

Preparing chitosan solutions from shrimp shells for rice production was investigated. The chitosan produced from shrimp shells using dilute acetic acid proved effective in controlling plants infection by microbial agents leading to higher yields. The field data of our studies showed that the yields of rice significantly increased (~31%) after applying chitosan solution. In general, applying chitosan increased rice production and reduced cost of production significantly.Keywords: Chitosan solution, rice production, common brown backed rice plant hoppersAfrican Journal of Biotechnology Vol. 12(4), pp. 382-38

Erratum: Mott Transition in the Mass Imbalanced Ionic Hubbard Model at Half Filling

Erratum: Mott Transition in the Mass Imbalanced Ionic Hubbard Model at Half Filling[Nguyen Thi Hai Yen, Le Duc Anh, Hoang Anh Tuan, Nguyen Toan Thang and Tran Thi Thu Trang, Communications in Physics, Vol. 29, No. 3SI (2019), pp. 305-312]This paper was published on 22 October 2019 with an omission in the text of the author’s list. The author list should read asNGUYEN THI HAI YEN$^1$, LE DUC ANH$^2$, HOANG ANH TUAN$^{1,3,\dagger}$, NGUYEN TOAN THANG$^1$, TRAN THI THU TRANG$^4$ AND NGUYEN THI HUONG$^5$$^1$Institute of Physics, Vietnam Academy of Science and Technology (VAST), Hanoi, Vietnam $^2$Hanoi National University of Education, Hanoi, Vietnam $^3$Graduate University of Science and Technology, VAST, Hanoi, Vietnam $^4$Ha Long University, Quang Ninh, Vietnam $^5$Thuy Loi University, Hanoi, Vietnam$^{\dagger}$E-mail: [email protected] author’s list has been corrected as of 29 November 2019. The author’s list has been corrected in the electronic version of the journal

3D-BIM and 4D-BIM Models in Construction Safety Management

The application of modern technologies into on-site construction safety management has been proved that be successful. BIM technology which has been studied and developed for adopting widely in the construction industry is promised to bring significant improvements in construction safety management. The article reviewed the application of BIM in the management of construction safety, detailed for each safety work activity. Suggestions for selecting BIM tools in the management of construction safety are also listed. Lastly, the article poses some obstacles while applying BIM to construction safety management in Vietnam

Invited; Microfabrication of BiTeSb thermoelectric devices for applications to IoT sensors

In this study, thermoelectric power generation devices and an energy harvesting system to generate electricity from a low-quality heat source or environmental temperature fluctuation near room temperature are developed. Thermoelectric power generators (TEG) composed of Bi2Te3-Sb2Te3 with metal nanoparticles are microfabricated using electrodeposition of the thermoelectric materials and microfabrication technology (Figs 1 and 2). Using the fabricated TEG, the temperature-fluctuation thermoelectric power generation (TF-TEG) unit is developed. As shown in Fig. 3, a heat storage material (phase change material: PCM) was contacted to one side of the thermoelectric element, and the other side was made to exchange heat with the outside air. Please click Download on the upper right corner to see the full abstract

Factors contributing to animal health risks: Implication for smallholder pig production in Vietnam

In Vietnam, there are about four million households producing pigs of which more than half are producing at small scale, i.e., about one to two pigs per production cycle. One of the most critical constraints to pig production, especially for small scale, is the presence of animal disease. Many types of diseases have been reported by smallholder pig producers in Hung Yen such as diarrhea, pneumonia, fever, blue ear, head edema and pasteurellosis. The percentage of sick pigs is highest among piglets (27 percent), as compared with growing pigs and fatteners (five percent each). Diseases could lead to death of pigs, resulting in economic losses to the pig producers. Estimates of the cost of mortality in pig production in Hung Yen were about 3.3 million VND per household, accounting for about 13.6 percent of total income from pig production. Results of this study suggest that there are some practices that contribute to mitigating disease risk and those practices can be easily applied at small scale of pig production. These practices are related to applying a suitable production scale, isolating different age classes of pigs, designing pig houses and using specialized livestock farming tools and sanitation. The value of losses avoided from the above practices is estimated at 320.3 USD per household per year