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Chitosan samples was prepared from squid pens (-chitosan) with degree of deacetylation (DD) ~ 70%. The oxidation degradation of -chitosan (βCTS) by hydrogen peroxide in heterogeneous and homogeneous medium have been studied. The oxidation degradation rate constants (kox) have been determined: 0.18  10-4 h-1 in heterogeneous medium and 0.48 ...

9 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 598 | Lượt tải: 0

Abstract: In this work we take into consideration the calculation of the photodetachment cross section of negatively charged hydrogen ions through the use of an effective-charge model and the two-electron Green’s function for summation over final states of the system. The analytical form of this function is obtained by the convolution of the one...

6 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 735 | Lượt tải: 0

Abstract: In this article, we report the biological synthesis of silver nanoparticles from silver nitrate solution using aqueous extract of lemongrass leaf as reducing agent. The influence of some factors such as the volume ratio of lemongrass leaf extract/AgNO3 solution, pH, and temperature to he ynthesis of silver nanoparticles was investigate...

5 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 577 | Lượt tải: 0

ABSTRACT: Activated carbon (AC) was prepared from coffee husk and modified by nitric acid for effective lead ions removal from aqueous solution. The as-prepared samples have uniform particles size, developed surface area and contain acidic surface functional groups. Nitric acid modification showed a pronounced effect on improving Pb(II) adsorpti...

10 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 976 | Lượt tải: 0

Nd-doped BiFeO3 materials were synthesized via a sol–gel method. The crystal structure, magnetic properties, and complex impedance spectroscopy of multiferroic Bi1-xNdxFeO3 (BNFO) materials were investigated by Xray diffraction (XRD), Raman scattering, vibrating sample magnetometer (VSM), and complex impedance spectroscopy. Our results show that ...

84 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 600 | Lượt tải: 0

Abstract The polyvinyl alcohol (PVA)-capped ZnS:Mn nanoparticles with Mn content of 8 mol% and different PVA mass (denoted as ZnS:Mn/PVA) are synthesized by co-precipitation method, in which PVA solution is mixed from the beginning with the initial solutions used to synthesize ZnS:Mn nanoparticles. The microstructures, morphology and average cry...

17 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 510 | Lượt tải: 0

Tóm tắt: Từ dịch chiết nước củ nghệ và dung dịch AgNO3 đã tổng hợp được hạt nano bạc có khả năng xúc tác cho phản ứng khử p-NP/NaBH4. Chứng minh được nano bạc điều chế với điều kiện: tỉ lệ rắn / lỏng: 3g / 200mL; thời gian chiết: 2h30ph; nồng độ AgNO3: 1mM; tỉ lệ dịch chiết / AgNO3: 6mL / 20mL cho hiệu suất khử p-NP bằng NaBH4 cao nhất, đạt 95% ...

5 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 902 | Lượt tải: 0

ABSTRACT: The research results of poly(1-naphthylamine)/Fe3O4 (PNA/Fe3O4) nanocomposites synthesized by a chemical method for As(III) wastewater treatment are presented in this paper. XRD patterns and TEM images showed that the Fe3O4 grain size varied from 13 to 20 nm. The results of Raman spectral analysis showed that PNA participated in part o...

10 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 662 | Lượt tải: 0

The research results of Fe3O4 and Mn, Cu doped Fe3O4 nanomaterials synthesized by a chemical method for As(III) wastewater treatment are presented in this paper. The X-ray diffraction patterns and transmission electron microscopy images showed that samples had the cubic spinel structure with the grain sizes were varied from 9.4 nm to 18.1 nm. The...

7 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 640 | Lượt tải: 0

This paper reports the application of the Ru2þ, Cuþ, and Fe2þ complexes in form of RuL2(SCN)2, CuL2(SCN)2 for dye-sensitized solar cell (DSSC) development. The calculation results, given by quantum chemistry, demonstrated that the complex containing copper is more suitable than the one containing iron. The modification of Cu(I) complex by using v...

5 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 620 | Lượt tải: 0