Optical Properties of Silicon Nanoparticles Prepared by Laser Ablation Method in Various Media

Bright photoluminescent silicon nanoparticles were successfully fabricated from porous silicon target in air and n-hexane using 532 nm line of YAG:Nd pulsed laser. The whole procedure was carried out at room temperature, in atmosphere. The morphology and composition of as-synthesized nanoparticles were characterized by SEM and EDS measurements. Their optical properties were investigated. The PL peak position of the as-synthesized Si nanoparticle ablated in air is slightly blue-shifted in comparison with those ablated in n-hexane, while it was almost no change of peak position of Si nanoparticles fabricated from p-Si in hexane and original p-Si wafer target. In contrast to PL intensity quenching of original p-Si sample and particles produced in air, those produced in n-hexane solvent exhibited an enhancement. The presence of dangling bonds or energy transfer from excited Si particles to oxygen molecules on the surface can be the cause of the quenching effect

Seed Health and Quality of Rice Seeds Produced by Farmer and Growing in Cho Moi District, An Giang Province, Vietnam

This study was conducted at Laboratory in An Giang University; the varieties examined were collected from farmer households in 2018 – they were varieties that the farmer stored for the next crop (Winter-Spring) from Autumn-Winter crop in Cho Moi district, An Giang Province, Vietnam. The research evaluated the quality of seed rice, which is provided and planted by the farmer. As a result, this study showed that almost all of the varieties of seed rice from farmer households indicated the ratio of filled-grain, the germination, and the determination of seedling healthy, which are lower than certified variation. Besides, the samples of seed rice from farmer household have more infected fungal; especially the samples with higher in a filled-grain ratio is less infected by fungi, there were 12 types of seed borne-fungi in rice varieties from the farmer (in Cho Moi district), included: Alternaria padwickii, Rhizoctonia solani, Aspergillus oryzae, Bipolaris oryzae, Cercospora janseana, Curvularia lunata, Fusarium moniliforme, Pyricularia oryzae, Sarocladium oryzae, Tilletia barclayana, Fusarium graminearum, and Ustilaginoidea viren

Effectiveness of perindopril/amlodipine fixed-dose combination in the treatment of hypertension: a systematic review

Background: Uncontrolled blood pressure is a major risk factor for cardiovascular diseases. Fixed-dose combination (FDC) therapy offers a promising approach to addressing this challenge by providing a convenient single-tablet solution that enhances the effectiveness of blood pressure control. In our systematic review, we assess the effectiveness of perindopril/amlodipine FDC in managing blood pressure.Methods: We conducted a comprehensive search across four primary electronic databases, namely, PubMed, Virtual Health Library (VHL), Global Health Library (GHL), and Google Scholar, as of 8 February 2022. Additionally, we performed a manual search to find relevant articles. The quality of the selected articles was evaluated using the Study Quality Assessment Tools (SQAT) checklist from the National Institute of Health and the ROB2 tool from Cochrane.Results: Our systematic review included 17 eligible articles. The findings show that the use of perindopril/amlodipine FDC significantly lowers blood pressure and enhances the quality of blood pressure control. Compared to the comparison group, the perindopril/amlodipine combination tablet resulted in a higher rate of blood pressure response and normalization. Importantly, perindopril/amlodipine FDC contributes to improved patient adherence with minimal side effects. However, studies conducted to date have not provided assessments of the cost-effectiveness of perindopril/amlodipine FDC.Conclusion: In summary, our analysis confirms the effectiveness of perindopril/amlodipine FDC in lowering blood pressure, with combination therapy outperforming monotherapy and placebo. Although mild adverse reactions were observed in a small subset of participants, cost-effectiveness assessments for this treatment remain lacking in the literature

Physiological properties of new species of Acidithiobacillus isolated from abandoned Tin mine in Ha Thuong, Thai Nguyen province: Research article

Acidophilic bacteria are able to tolerate acidic environment and also contribute to the lowering of environmental pH value, implying potential applications in metal-leaching technology extracting metals from tailings and electronic wastes. In this study, we conducted a sampling campaign in abandoned Tin mine in Ha Thuong, Thai Nguyen province, to isolate acidophilic bacteria and to study physiological characteristics of the isolated bacteria. As a result, two acidophilic bacteria were successfully isolated and identification by 16S rDNA gene sequences showed that the two bacteria are similar to Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans (98% and 94 % of similarity, respectively). Both strains are tolerant of pH in the range of 3 and have the ability to grow optimally at temperatures of 30°C.Vi khuẩn ưa axit có ý nghĩa ứng dụng trong công nghệ tách rút kim loại từ quặng đuôi và ngay cả từ rác thải linh kiện điện tử. Trong nghiên cứu này, chúng tôi đã tiến hành thu mẫu ở mỏ thiếc bỏ hoang ở Hà Thượng, Thái Nguyên nhằm phân lập được nhóm vi khuẩn ưa axit và qua đó nghiên cứu một số đặc điểm sinh lý của vi khuẩn này. Kết quả chúng tôi đã phân lập được hai chủng vi khuẩn ưa axit. Định dạng bằng nhận diện trình tự gen 16S rADN cho thấy hai vi khuẩn này có độ tương đồng là 98% với vi khuẩn Acidithiobacillus ferrooxidans và 94% Acidithiobacillus thiooxidans. Cả hai chủng vi khuẩn đều có tính chịu pH trong khoảng 3 và có khả năng sinh trưởng tối ưu ở nhiệt độ 30oC

Physiological properties of new species of Acidithiobacillus isolated from abandoned Tin mine in Ha Thuong, Thai Nguyen province: Research article

Acidophilic bacteria are able to tolerate acidic environment and also contribute to the lowering of environmental pH value, implying potential applications in metal-leaching technology extracting metals from tailings and electronic wastes. In this study, we conducted a sampling campaign in abandoned Tin mine in Ha Thuong, Thai Nguyen province, to isolate acidophilic bacteria and to study physiological characteristics of the isolated bacteria. As a result, two acidophilic bacteria were successfully isolated and identification by 16S rDNA gene sequences showed that the two bacteria are similar to Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans (98% and 94 % of similarity, respectively). Both strains are tolerant of pH in the range of 3 and have the ability to grow optimally at temperatures of 30°C.Vi khuẩn ưa axit có ý nghĩa ứng dụng trong công nghệ tách rút kim loại từ quặng đuôi và ngay cả từ rác thải linh kiện điện tử. Trong nghiên cứu này, chúng tôi đã tiến hành thu mẫu ở mỏ thiếc bỏ hoang ở Hà Thượng, Thái Nguyên nhằm phân lập được nhóm vi khuẩn ưa axit và qua đó nghiên cứu một số đặc điểm sinh lý của vi khuẩn này. Kết quả chúng tôi đã phân lập được hai chủng vi khuẩn ưa axit. Định dạng bằng nhận diện trình tự gen 16S rADN cho thấy hai vi khuẩn này có độ tương đồng là 98% với vi khuẩn Acidithiobacillus ferrooxidans và 94% Acidithiobacillus thiooxidans. Cả hai chủng vi khuẩn đều có tính chịu pH trong khoảng 3 và có khả năng sinh trưởng tối ưu ở nhiệt độ 30oC

TỔNG HỢP VẬT LIỆU KHUNG HỮU CƠ KIM LOẠI ZIF-67 VÀ BIẾN TÍNH ĐIỆN CỰC THAN THỦY TINH ĐỂ XÁC ĐỊNH DOPAMINE VÀ PARACETAMOL

In this study, we present the results of the synthesis of the metal-organic framework material ZIF-67 and its application to modify an electrode for the simultaneous voltammetric determination of dopamine and paracetamol. The obtained materials were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), and nitrogen adsorption/desorption isotherm. The ZIF-67 modified electrode was used to develop an electroanalytical method that can be used to simultaneously quantify dopamine and paracetamol. The results show that under microwave irradiation, the size and morphology of ZIF-67 crystals tend to be more uniform and regular with a high surface area (1935.07 m2/g). The limit of detection of the method for DPA and PRA is 0.39 mM and 0.51 mM, respectively.Bài báo trình bày những kết quả nghiên cứu tổng hợp vật liệu khung hữu cơ – kim loại ZIF-67 và ứng dụng biến tính điện cực để xác định đồng thời dopamine (DPA) và paracetamol (PRA). Vật liệu tổng hợp được xác định các đặc trưng bằng phương pháp hiển vi điện tử quét (SEM), nhiễu xạ tia X (XRD) và đẳng nhiệt nhiệt hấp phụ và giải hấp phụ nitơ. Điện cực biến tính bằng vật liệu ZIF-67 được sử dụng để phát triển phương pháp volt-ampere hòa tan để xác định đồng thời paracetamol và dopamine. Các kết quả cho thấy kích thước và hình thái của tinh thể ZIF-67 thu được từ phương pháp vi sóng có khuynh hướng đồng nhất và đều với diện tích bề mặt riêng lớn (1935,07 m2/g). Giới hạn phát hiện của phương pháp thấp đối với DPA (0,39 mM) và PRA (0,51 mM)

Removal of Tetracycline from Aqueous Solution Using Nanocomposite Based on Polyanion-Modified Laterite Material

This work investigated the removal of antibiotic tetracycline (TC) from wastewater using nanocomposite material based on laterite modified with polyanion, polystyrene sulfonate (PSS). The effective factors influenced on the TC removal using nanocomposite PSS-modified laterite (NCPML) were optimized and found to be pH 4, solid-liquid ratio 5 mg/mL, and contact time 180 min. The highest removal of TC reached about 88% under the optimum adsorption conditions. The adsorption isotherm and kinetics of TC adsorption onto NCPML were in good agreement with the Langmuir and pseudo-second-order models, respectively. The characteristics of the NCPML material before and after TC adsorption were examined by zeta (ζ) potential measurements, Brunauer–Emmett–Teller (BET) method, and Fourier transform infrared spectroscopy (FT-IR). The TC adsorption onto NCPML was induced by electrostatic interaction, hydrogen bonding, and diffusion interaction. The TC removal from wastewater was approximately 94% while efficiency still reached 66% after five regenerations. Our research reveals that NCPML is a high-performance adsorbent for TC removal from wastewater

Smartphone-Based Sensing for Intelligent Inland Waterway Transportation

In this paper, we present an Android application, namely BoatSafe, which offers easy and effective navigation of waterways. The data were collected directly from both GPS and the accelerometer sensor, and then these data were processed to determine the user's "Sailing on Water" status through the motions and the position. The software offers some essential features such as: provide the positions, velocities, and heading angle of vehicles at present; save the route for a specific period time; identify the outage of GPS signal; collision warning feature, identify a collision, and call a pre-selected phone number in the event of a collision.</span