Science and Technology Development Journal - Natural Sciences

Journal Information
ISSN / EISSN : 2588-106X / 2588-106X
Current Publisher: Viet Nam National University Ho Chi Minh City (10.32508)
Former Publisher: Biomedical Research and Therapy (10.15419)
Total articles ≅ 346
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Quang Đại Tran, Hoang Van Nguyen, Mẫn Văn Trần, Phụng Mỹ Loan Lê
Science and Technology Development Journal - Natural Sciences, Volume 4; doi:10.32508/stdjns.v4i4.911

Abstract:
High voltage cathode LiCoPO4 has been taken great interest for high power Li-ion batteries (LIBs). Though Co enhance the cyclability, capacity of materials, Co concentration should be reduced in electrode materials due to its high cost and toxic. In this work, the solvo-thermal reaction following by pyrolysis in inert Ar was investigated to synthesize the electrode materials LiFexCo1-xPO4 (0.1
Trang Thị Thu Nguyễn, Ý Thị Đặng, Linh Hồ Thùy Nguyễn, Hạnh Thị Kiều Tạ, Thắng Bách Phan, Tân Lê Hoàng Đoàn
Science and Technology Development Journal - Natural Sciences, Volume 4; doi:10.32508/stdjns.v4i4.927

Abstract:
Highly porous and biocompatible nano metal-organic framework materials (NMOF) are increasingly being applied in biomedical fields, especially as pharmaceutical adsorbent materials. Curcumin, found in turmeric, is a widely common herb in Eastern which has recently used in many applications in supporting cancer treatment. In the synthesis of MOF materials, the use of surfactants allows to control the morphology, the process of crystal formation and development and particle size of the material. In this research, MIL-100 (Fe) nanomaterials were successfully synthesized at room temperature in the presence of polyvinylpyrrolidone surfactant (PVP) to control the nanoparticle size about 50 nm in size. The synthesized MOF structure and properties were analyzed by using characterization techniques, including powder X-ray diffraction (PXRD), fourier-transform infrared (FT-IR), thermal gravimetric analyses (TGA) and nitrogen isothermal adsorption-desorption at 77 K. The characterization results showed that MIL-100 (Fe) nanomaterials have high crystallinity, large surface area, and highly thermal stability. However, its particle size is very small, only about 50 nm. Curcumin adsorption studies exhibited that this material had the ability to adsorb curcumin with an adsorption capacity up to 64.36 mg g-1. Kinetic and mechanism studies revealed that curcumin adsorption followed the pseudo-second model. In addition, thermodynamic studies proved that this was a spontaneous and exothermic adsorption process.
Nhan Chi Nguyen, Khang Phuoc Hoang Nguyen, Quan Hoang Nguyen, Hieu Van Nguyen, Huy Thanh Ho
Science and Technology Development Journal - Natural Sciences, Volume 4, pp 800-810; doi:10.32508/stdjns.v4i4.951

Abstract:
This paper presents the design of environmental monitoring and control system in aquaponics based on Internet of Things (IoT) technology. This system allows users to monitor and control the operation of devices through the application on smartphones, including: 3 water pumps, 3 air pumps, pH sensor, dissolved oxygen (DO) sensor, temperature sensor and humidity sensor, exhaust fan and misting. These devices are monitored and controlled in two modes: automatic and manual control. For 3 pumps and 3 air pumps, in automatic mode, allows the user to set the pump time between water pumps and between air pumps. In manual control mode, allows the user to control water pumps and air pumps by the push of a button on a smartphone application. Monitor pH, DO and allows the user to set the pH threshold and DO threshold to give an alert when the pH and DO exceed the threshold. Monitor the parameters of temperature, humidity in the membrane house and allow setting the temperature threshold and humidity threshold to control the exhaust fan and misting respectively when the temperature and humidity exceed the threshold. This system tested at aquaponics farm - Dong Thap Aqua. The results show that this system is working reliably and promising which brings significantly benefits to aquaponics. Besides, it also contributes to improve production efficiency and sustainable development of green agriculture.
Thao Thi Phuong Dang, Linh My Dao, Anh Man Huynh, Dan Thi Hanh Vo
Science and Technology Development Journal - Natural Sciences, Volume 4, pp 811-817; doi:10.32508/stdjns.v4i4.929

Abstract:
Metabolic syndrome is a collection of disorders related to metabolisms such as obesity, lipid disorders, hyper/hypoglycemia, ... Metabolic syndrome can lead to cardiovascular diseases, strokes, and diabetes - the leading death causes in the world. In many cases, metabolic disorders are original by the redundant/ reduction of insulin- the most important hormone in metabolism regulation. Both of them are involved in beta-cells dysfunction. Many mechanisms related to this phenomenon has been approved, notably mitochondrial dysfunction and the Ubiquitin proteasome system impairment. UCH-L1 is a protein belonging to the Ubiquitin proteasome system and highly expressed in beta cells. Previous studies reported that decrease UCH-L1 function can alter metabolism and lead to b cell apoptosis under various nutritional conditions, however, the mechanism has not been clarified. In this study, we proposed a Drosophila melanogaster model that expresses many symptoms of metabolic syndrome, by knocking down dUCH (Drosophila homolog of UCH-L1) specifically in Insulin-producing cells. Our fruit fly model had abnormal metabolism, physiology, loss of insulinproducing cells, and mitochondria over-workload, similar to metabolic syndrome in humans. These results suggested that this model is suitable for further studies on the role of UCH-L1 in b cells, as well as a potential model in metabolism diseases' drug screening.
Hoa Van Nguyen, Phi Minh Nguyen, Thien Ngoc Nguyen, Dao Minh Chau, Hanh Thi Thu Tran
Science and Technology Development Journal - Natural Sciences, Volume 4; doi:10.32508/stdjns.v4i4.652

Abstract:
The phonon calculations of hydrogen when adsorbed on the missing row Pt(110)-(1x2) surfaceusing the Ultrahigh Vacuum (UHV) model were studied. The calculations were based on a combinationof Density Functional Theory (DFT) and the approximation of hydrogen vibrations on thesurface. The harmonic vibration of H on the Pt surface was used for the calculation in this study. Atthe hydrogen coverage of 1ML for the model surface (when H completely covering the Pt surface),the interaction formed at the edge of the first layer (short bridge - R) was the most stable. The lessstable positions were recorded as the bridge position between two atoms on a horizontal row inthe second layer (trough - T), the top position of the second surface layer - fcc (F), the bridge positionof the second surface layer - hcp (F'), and the least stable position was the top position of thefirst layer (T'). When accounting the quantum calculation for the model, the adsorption energy ofhydrogen at the short bridge position increased by 90 meV, and the stable adsorption order of hydrogenchanged with the most stable positions ware R, T, T', F', F respectively. This demonstratesdthe significant influence of quantum effects on the adsorption model.
Nhi Nguyen Y Ha, My Ngoc Diem Tran
Science and Technology Development Journal - Natural Sciences, Volume 4, pp 776-788; doi:10.32508/stdjns.v4i4.863

Abstract:
The purpose of research is studying the variation of zooplankton community in Ba Lai river in Ben Tre province. Research was conducted in 2 seasons: rainy season (December, 2017) and dry season (March, 2018). There were 7 sampling points in Ba Lai river, Ben Tre province. Our study recorded 95 taxa zooplankton belong to 56 genera, 39 families, 12 orders, 8 classes and 5 phylums. Generally, Rotifers had highest munbers of species among 2 seasons. Rotifers were dominant in density and species composition at all sampling points in the rainy season. Copepods were dominant in density and species composition in the dry season. There were some marine species present at sampling points during the dry season. In addition, the Bray - Curtis analysis showed that the similarity of the zooplankton communities between rainy season and dry season at sampling points wasnot high. This suggests that there was a shift in the structure of the zooplankton community between rainy season and dry season. These are proof to prove the salinity rising in Ba Lai river in dry season. Although there is an irrigation dam to prevent the infiltration of salt water, but the infiltration of salt water is happening. A solution to preserve fresh water to provide local people in dry season is necessary.
Đào Thi Băng Tâm, Nguyễn Trung Độ, Lưu Kiến Quốc, Hà Thúc Chí Nhân
Science and Technology Development Journal - Natural Sciences, Volume 4, pp 789-799; doi:10.32508/stdjns.v4i4.915

Abstract:
Heavy metals are known to be toxic, even at low content (ppm), for living organisms[1,2]. The presence of heavy metals and other pollutants in water continues to be a major concern and the removal of such contaminants is considered as an important solution for environmental remediation[3,4]. In this paper, we study the ability adsorption of Pb2+ and Cd2+ heavy ionic metal on silica nanomaterials which was extracted and purified from Vietnamese rice husk. The structure of the materials was investigated by X-ray diffraction (XRD) and FT-IR spectroscopy. By Adsorption Atomic Spectroscopy (AAS) analysis, the results have demonstrated the time taken for attaining equilibrium adsorption is about 1.5 hours for both cases, and the adsorption capacity of Pb2+ and Cd2+ on silica are 21 and 24 mg/L, respectively.
Thai Thanh Tran, Nguyen Le Que Lam, Nguyen Thi My Yen, Pham Thanh Luu, Tran Thi Hoang Yen, Nguyen Thi Huynh, Lam Van Tan, Ngo Xuan Quang
Science and Technology Development Journal - Natural Sciences, Volume 4; doi:10.32508/stdjns.v4i4.866

Abstract:
Nematode communities were used as a tool to assess the environmental quality status of sediment of the water bodies in Ben Tre city. Eight locations in the main canals and river in the city were surveyed during the rainy season (September). The study recorded 51 genera belonging to 33 families, 10 orders (Araeolaimida, Chromadorida, Desmodorida, Dorylaimida, Enoplida, Monhysterida, Mononchida, Plectida, Rhabditida, and Triplonchida), 2 classes (Chromadorea and Enoplia). The density of nematode communities at most survey locations is quite high, ranging from 29.88 +/- 38.01 to 1172.08 +/- 659.74 individuals/10 cm2. However, the biodiversity is quite low, species richness index (S) ranged from 5.33 1.15 to 18.33 4.72, and Shannon diversity index (H') from 1.28 +/- 0.12 to 3.19 +/- 0.50 and Pielou's evenness index (J') from 0.47 +/- 0.04 to 0.93 +/- 0.04. The Maturity Index (MI) of nematode communities was applied to assess the environmental quality status of sediment. The results showed that the environmental quality status of sediment recorded disturbances, classified as bad to moderate. The colonizer-persister (c-p) combined with the MI is a potential tool in biological monitoring of environmental quality status. However, to increase the reliability of evaluation conclusions, the combination of MI and biological indicators as well as physical-chemical parameters is necessary.
Dien Thi Kieu Pham, Kiet Thuong Do, Sanh Du Nguyen
Science and Technology Development Journal - Natural Sciences, Volume 4; doi:10.32508/stdjns.v4i4.891

Abstract:
The cherry tomato fruit size depends on the growth of the pericarp which is parenchymal cells. The blue light stimulates the expansion of cotyledon cells, hypocotyl cells and leaf cells. In this study, the cherry tomato fruit was used as a material to investigate the effects of the blue light on the pericarp cells growth in fruit growth stage and lycopene accumulation in fruit growth and ripening stage. After 7 days of the blue light (440, 450 or 460 nm) treatment, pericarp cells growth and physiological, biochemical changes of the pericarp cells of 7-day-old fruit pericarp piece in vitro were analyzed. The lycopene content and some organic compound contents of 42-day-old postharvest fruits treated by the blue light similarly in 7 days and 7, 21-day-old fruit wrapped with blue filter (440-510 nm filtered) in 7 days were measured. The results showed that the 450 nm wavelength blue light the increased pericarp thickness of 7-day-old fruits through the increasement of the pericarp cell diameter. The 460 nm wavelength blue light the increased lycopene content of 42-day-old postharvest fruits. The blue filter treatment increased the sugar total content of 7- day-old fruits and increased the lycopene content of 21-day-old fruits.
Nguyen Ngoc Anh, Nguyen Xuan Hai, Hồ Hữu Thắng, Phan Bao Quoc Hieu, Truong Van Minh
Science and Technology Development Journal - Natural Sciences, Volume 4; doi:10.32508/stdjns.v4i4.860

Abstract:
The present paper proposes an algorithm to improve the energy resolution of two-step cascade spectrum. The energy resolution plays an important role in the domain of gamma spectrum analysis. The better the energy resolution is, the better the ability of peak resolving is. The algorithm is constructed based on an analyze of energy resolution of the summation amplitude of coincident pulses spectrometer using the analogue technique. The algorithm proposed has been tested on some two-step cascade spectra of 164Dy nucleus obtained from the (n, ) reaction experiment using the gamma – gamma coincidence spectrometer at Dalat Nuclear Research Institute. Two-step cascade spectra corresponding to the cascade decays from the compound state to final states whose energies are 0, 74, and 242 keV have been evaluated. The results obtained show that the energy resolution of the two-step cascade spectrum has been reduced by 1.05 to 2.04 times within the energy range of 586 to 6830 keV. Our algorithm can therefore be applied to improve the ability of peak deconvolution, the accuracy, and the realibility in analyzing two-step cascade spectra.
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