Chemical methods

Study on the actual situation of domestic water of 24 military units in the Northern region in 2022. Subjects and methods: A descriptive cross-sectional study with analysis and evaluation of seven basic physical, chemical and microbiological indicators on 113 samples of domestic water collected at 24 military units stationed in the Northern Region from July to October, 2022.

4p vipanly 28-10-2024 2 0   Download

The objective of this study is to analyze the chemical speciation of Pb in sediment samples from the Than Sa gold mining area to obtain comprehensive information regarding the level of Pb contamination in sediment samples from this area.

9p viengfa 28-10-2024 2 0   Download

Silver nanoparticles (Ag NPs) were synthesized and characterized by transmission electron microscopy (TEM), X-ray powder diffraction (XRD), and absorption spectroscopy. Using Debye-Scherrer’s formula and the result of the XRD spectrum, the size of the Ag NPs was estimated at approximately 8 nm.

7p viengfa 28-10-2024 0 0   Download

In this study, we investigated some conditions affecting the extraction of total carotenoids from R. mucilaginosa using environmentally friendly chemicals: cell disruption conditions with organic acids combined with ultrasound-assistant method, using ethanol and petroleum ether solvents to replace acetone in the process of extracting total carotenoids to obtain a benign product, easy to apply in food.

8p viling 11-10-2024 1 0   Download

In the present work, CeO2 with different loading was embedded on reduced graphene oxide (rGO) by a simple one-pot hydrothermal method. The synthesized samples were characterized using XRD, EDX mapping, FESEM, and UV-Vis DRS techniques.

11p vifilm 11-10-2024 2 0   Download

In this report, the solid phase extraction technique combined with the gas chromatographymass spectrometry method (GC-MS) was optimized to determine the contamination of nine phthalic acid esters (PAEs) in the surface sediment samples collected from Rao Cai River in Ha Tinh, Vietnam.

7p vifilm 11-10-2024 0 0   Download

Zeolite, as chemical essence, is an aluminosilicate mineral synthesized by richsilica source, such as rice husk ash (RHA). This study focuses on the synthesis of zeolite NaP1 under a facial hydrothermal method using the silica source utilized from RHA without any-pretreatment steps.

6p vikwong 29-09-2024 2 1   Download

Manufactured dyes are notably troublesome chemical toxins. The industrial wastes of these dyes are exceedingly noxious to aerobic and aquatic life and can cause compounds that show carcinogenic, mutagenic, and neurotoxic effects. In this study, cadmium imidazolate frameworks were synthesized by a solvothermal method from cadmium acetate and 2-methylimidazole in an ethanol/methanol mixture.

7p vikwong 29-09-2024 3 1   Download

TiO2 thin films were synthesized by using Chemical Vapor Deposition (CVD) method on different substrates, such as glass, aluminium foil , and ceramic. The samples had been characterized by microscopy analysis, SEM, and EDS. The results show that TiO2 thin films were successfully fabricated and TiO2 nanocrystals with size of 50-100 nm loaded uniformly on surface of different substrates.

6p vikwong 29-09-2024 3 1   Download

Titanium oxides nanotubes (TNTs) were prepared by hydrothermal method and used as nano-support for nickel nanoparticles. Indeed, nickel nanoparticles supported TNTs (Ni-TNTs) were in situ synthesized from nickel salt and TNTs by chemical reduction method using sodium borohydride (NaBH4) as reducing agent.

5p vikwong 29-09-2024 4 1   Download

Alginate-stabilized Cu2O@Cu nanoparticles were fabricated by chemical reduction method using nature polymer alginate as a stabilizing agent. Transmission electron microscopy (TEM), X-ray powder diffraction (XRD), infrared (FT-IR) spectrum, and UV-Vis analysis were used to investigate the morphology, size, structure, and stability of the nanoparticles synthesized.

6p vikwong 29-09-2024 5 1   Download

Cordierite is the substrate that posseses a low thermal expansion coefficient, good thermal shock resistance, excellent mechanical properties, and chemical resistance. Thus, cordierite is widely used as substrate for catalysts in hightemperature applications like gaseous treatment.

7p vikwong 29-09-2024 2 1   Download

The green production of hydrogen peroxide has attracted considerable attention owing to the urge for an alternative production method to the current production. Electrocatalytic reduction via the 2e- pathway has emerged as the brightest approach.

6p vikwong 29-09-2024 3 2   Download

The article presents some results of investigating the effective adsorption ratio of base oil SN 100 on silica gel, determination of physico-chemical, electrical properties, and voltage stability of the oil fraction which is separated from base oil SN 100 by adsorption method on silica gel with the appropriate ratio of silica gel/base oil SN 100 = 140/100.

5p vikwong 29-09-2024 2 1   Download

Buxus latistyla Gagnep. (Buxaceae) has been used as a remedy for treating malaria, haemoptysis, amoebic dysentery etc. However, its chemical constituents are still unknown. Thus, the aim of this study was to identify phytochemicals isolated from this plant.

7p vifaye 20-09-2024 3 1   Download

This work demonstrates an AlGaN/GaN high electron mobility transistor (HEMT) with Cr/Graphene ohmic contacts constructed without heat treatment. The Cr/Graphene ohmic contact was fabricated using a spray-coated graphene nanoflakes solution and electron-beamevaporated Cr. This method does not require a high-temperature annealing step in conventional Ti/Al/Ni/Au ohmic contact. It is suggested that the Cr/graphene combination acts similarly to a doped n-type semiconductor in contact with AlGaN/GaN heterostructures, enabling carrier transport to the AlGaN layer.

8p xuanphongdacy06 18-09-2024 3 1   Download

In this study, Zinc oxide (ZnO) nanoparticles with a size of about 50 - 70 nm were green-synthesized using tea leaves and ZnO/Polypyrrole (ZnO/Ppy) nanocomposites were obtained by ultrasonic-assisted chemical polymerization method using pyrrole monomer and the nanoparticles. The characterization of the materials is conducted using several analytical techniques, including Field Emission Scanning Electron Microscopy (FESEM) and X-Ray Diffraction (XRD) and Ultraviolet visible spectrum (UV-Vis).

11p xuanphongdacy06 18-09-2024 2 1   Download

CuO nanoparticles were synthesized by alcohol-assisted hydrothermal method at various pH values, using sodium hydroxide as a precursor for pH control. The chemical composition, morphological and structural properties of the obtained CuO nanoparticles were investigated by the Raman and energy-dispersive X-ray spectroscopies, the field-emission scanning electron microscopy, and the X-ray diffraction.

12p dianmotminh02 03-05-2024 3 1   Download

This article, we present a thorough and straightforward hydrothermal method towards the production of reduced graphene oxide templated MIL-53(Fe) hybrids RGO@MIL-53(Fe). The structural characteristics of created hybrids were identified by using BET, FESEM, powder X-ray diffraction, and FTIR techniques. Methylene blue (MB) dye (a model water pollutant) was used to evaluate H2O2-assisted photo-catalytic efficiency of RGO@MIL-53(Fe).

9p dianmotminh02 03-05-2024 4 2   Download

A major challenge for outdoor uses of methylammonium lead halide (MAPbX3) solar cells is the poor durability of the perovskite film under humidity. This instability is due to limitations of the dipping or spin coating process in producing MAPbX3 films through a direct reaction between PbI2 and methylammonium iodide (MAI) in an organic solvent. In this study, we devised an eco-friendly and cost-effective method to fabricate MAPbX3 films using an aqueous solution of Pb(NO3)2 and MAI vapour. I

7p dianmotminh02 03-05-2024 8 2   Download