TỔNG HỢP VÀ ĐẶC TRƯNG VẬT LIỆU KHUNG HỮU CƠ KIM LOẠI BIẾN TÍNH Fe-MIL-101

This paper presents the synthesis, structure, and morphology of the modified metal-organic framework Fe-MIL-101. The material was characterised using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), FT-IR spectra, energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectrum (XPS), and Brunauer-Emmett-Teller (BET) method for the specific surface area. The results showed that the obtained hybrid material Fe-MIL-101 with 10% replacement of iron has a homogeneous size with a typical octahedral structure, high crystallinity, and significant BET surface area of 2440 m2.g–1. The material is stable in nonpolar solvents and pH = 6.Nghiên cứu này trình bày quá trình tổng hợp và các đặc trưng của vật liệu khung hữu cơ kim loại biến tính Fe-MIL-101. Tính chất của vật liệu được xác định bằng phương pháp nhiễu xạ tia X (XRD), hiển vi điện tử quét (SEM), hiển vi điện tử truyền qua (TEM), phổ hồng ngoại (FT-IR), đẳng nhiệt hấp phụ và giải hấp nitơ (BET), tán xạ năng lượng tia X (EDX) và quang điện tử tia X (XPS). Kết quả cho thấy vật liệu Fe-MIL-101 với lượng sắt thay thế 10% có cấp hạt đồng đều, hình thái bát diện, độ kết tinh cao, diện tích bề mặt đạt 2440 m2/g. Vật liệu bền trong dung môi không phân cực ở pH = 6

NGHIÊN CỨU BAN ĐẦU VỀ HÌNH THÁI HANG CÁ KÈO VẢY TO PARAPOCRYPTES SERPERASTER

Cá kèo vảy to Parapocryptes serperaster là một trong những loài cá kinh tế ở vùng đồng bằng sông Cửu Long (ĐBSCL), chúng thường sống trong hang ở vùng đất bùn ở ao nuôi tôm quảng canh. Chúng có thể hô hấp bằng ôxy trên bề mặt của hang. Kết quả ban đầu về hình thái hang của loài này được nghiên cứu từ tháng 6 đến tháng 9 năm 2012 ở Gia Hòa 2, Mỹ Xuyên, Sóc Trăng, Việt Nam. Hang của chúng được đúc bằng cách đổ trực tiếp nhựa tổng hợp đã được pha với chất làm cứng vào miệng hang tại nơi thu mẫu. Hang của chúng có nhiều cửa vào (miệng), nhiều nhánh và nhiều chẩm (phần phình to ra lớn nhất của hang). Miệng hang của chúng không có ụ đất bao xung quanh, hang hơi nghiêng khi thông xuống chẩm và có nhiều nhánh cụt. Hang có đủ độ lớn để giúp chúng dễ dàng di chuyển ra khỏi miệng hang

EFFECT OF DIETARY SUPPLEMENTATION OF ETHANOL EXTRACT OF CHIVES AND GINGER ON THE PRODUCTIVITY AND HEALTH PERFORMANCE OF BROILERS

This study was to evaluate the effects of supplementation of ethanol extracts of chive (CE) and ginger (GE), and their combination (CG) in diets of broiler chickens on their growth, health performance and economic efficiency. Totally 180 male Egyptian broilers from one-day age were randomly assigned to 6 dietary treatments consisting of 3 replicates of 10 chicks each, of which in the diet of the control group (CT) neither ginger nor chive preparation were introduced, meanwhile the diets of birds in the 5 trial groups (CE1, CE2, GE1, GE2 and CG) were supplemented with 0.5% CE, 1% CE, 0.5% GE, 1% GE and 0.5% CE plus 0.5% GE preparations, respectively. In general, supplementation of CE and GE did not significantly affect feed consumption, mortality, performance efficiency index (PEI), and respiratory syndrome in chickens. However, the herb extract preparations could reduce the incidence of diarrhea in broiler chickens during five to-ten-week age periods. Microscopic examination of small intestinal mucosa showed that the heights of villi and the depths of crypts of chicks in the CE2 treatment as well as the diameters of villi of chicks in the CG treatment were significantly (p < 0.05) higher than in the others. In general, supplementation of 1% CE and the combination of 0.5% CE and 0.5% GE preparations improved the growth performance of broilers, and the combination can be an alternative to antibiotics as growth promoters in feeding chicken

Activity Concentrations of Sr-90 and Cs-137 in Seawater and Sediment in the Gulf of Tonkin, Vietnam

In this study, we measured the activity concentrations of Cs-137 and Sr-90 in surface seawater and surface sediments at the Tra Co, Bach Long Vi, and Ky Anh locations in the Gulf of Tonkin, Vietnam, from December 2018 to October 2019. The average activity at the selected locations was 1.22, 1.43, and 1.33 Bq/m3 for Cs-137 and 0.88, 1.17, and 1.09 Bq/m3 for Sr-90 in surface seawater samples and 0.74, 1.01, and 0.81 Bq/kg dry for Cs-137 and 0.49, 0.49, and 0.43 Bq/kg dry for Sr-90 in sediment samples. The ratio of the average activity concentration (Cs-137/Sr-90) in the surface seawater was 1.42, 1.22, and 1.22 at the Tra Co, Bach Long Vi, and Ky Anh locations, respectively. These are somewhat low compared to the global ratios (1.6 and 1.8). Meanwhile, Cs-137/Sr-90 ratios in the sediment samples at the selected locations were 1.51, 2.06, and 1.88, respectively, which is equal to or greater than the corresponding value for global sedimentation according to the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Correlations between Sr-90, Cs-137, and organic carbon content were detected in this study. The results showed that Cs-137 has a high correlation with the organic carbon content in sediment, while Sr-90 has a low correlation

Preparation of chitosan nanoparticles by spray drying and their antibacterial activity

[[abstract]]Chitosan nanoparticles were prepared from chitosan with different molecular weight by spray drying method. The morphology of chitosan nanoparticles were characterized by SEM and size distribution and zeta potential values were determined. Effect of chitosan solution concentrations, molecular weight of chitosan (MMW, HMW and VHMW) and size of spray dryer nozzles on average size, size distribution and zeta potential values of chitosan nanoparticles were investigated. Moreover, the effect chitosan nanoparticles and chitosan nanoparticles/amoxicillin complex on Staphylococcus aureus was also tested. The results showed that the average size of chitosan nanoparticles were in the range of 95.5 to 395 nm and zeta potential values of 39.3 to 45.7 mV depended on concentration and molecular weight of chitosan. The lower concentration and molecular weight of chitosan were used, the smaller size of chitosan nanoparticles and the higher zeta potential values were obtained. The testing for antibacterial activity against S. aureus indicated that chitosan nanoparticles strongly inhibited the growth of bacteria with the minimum inhibitory concentration (MIC) of 20µg/mL, which were lower than that of chitosan solution and amoxicillin. The antibacterial capacity of chitosan nanoparticles also depended on size, zeta potential values and molecular weight of chitosan. Complex of chitosan nanoparticles/amoxicillin could improve antibacterial activity of amoxicillin.[[notice]]補正完畢[[incitationindex]]SCI[[booktype]]紙本[[booktype]]電子