FIBERS AND POLYMERS
·
2016
·Vol. 17
·期 2
·194-198
·
IF 1.022
Xing Guiying
Aminated polyacrylonitrile (PAN-NH) nanofiber mats prepared by electrospinning and then aminated by multiamines with different chemical structures have been used for the immobilization of palladium. The PAN-NH fiber morphologies were characterized by scanning electron microscopy (SEM) and the dispersion of palladium particles on the PAN-NH fiber were examined by transmission electron microscopy (TEM). The catalytic activity and recyclability of the prepared heterogeneous palladium catalysts have been evaluated by the Heck reaction of iodobenzene with n -butyl acrylate. It was found that the catalytic activities of PAN-NH-Pd catalysts could be correlated with the chelating energies of the PAN-NH fiber mats with Pd active species.
研究领域:
化学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2022
·
IF 6.633
Xiu-Mei Song,Zong-Cai Feng,Yancheng Wu,Jiang-Li Song,Lu-Feng Wei,Shu-Yi Zeng
Two novel triphenylamine-based conjugated compounds were designed and synthesized. The compounds exhibited remarkable solvatochromism by changing emission colour from blue to yellow in polar organic solvents and were used as the fluorescent sensors for the detection of water in six common organic solvents, including acetonitrile, acetone, ethanol, tetrahydrofuran (THF), dimethylformamide (DMF) and dimethylsulfoxide (DMSO). Both sensors showed high sensitivity to detect water in the above-mentioned organic solvents in a wide range. The water sensing behavior of the sensors in acetonitrile was more effective, with a detection limit as low as 0.0079 v% and 0.0071 v%, respectively and a wide detection range (0–5.33 v%). Real application of the sensors was successfully carried out for detecting the unknown water content in commercial products, such as corn-starch, salt and sugar.
研究领域:
化学
·
分析化学
·
材料科学
✓ 已验证
DOI
高影响因子
Green Chemical Engineering
·
2020
·
IF 0
Xing Jiang,Jian Ren,Yong Kong,Zhiyang Zhao,Xiaodong Shen,Maohong Fan
The purpose of this study was to prepare a proof-of-concept CO 2 adsorbing material based on a new amine grafted silica aerogel microsphere (AGSAM) that could be used on both fixed and fluidized beds. A low-cost water glass and environment-friendly water were used as precursor and solvent of the silica aerogel, respectively. The silica aerogel microsphere (SAM) was prepared by dropping the siliceous solution into hot oil bath. The effect of the pH value of the siliceous solution, stirring speed and stirring paddle position on the sphericity and size of the SAM was investigated. The SAM with good sphericity was obtained when the pH value was 5.69–5.79. The mean diameter of the SAM decreased from 5 to 1 mm when the stirring speed increased from 1000 to 2000 rpm. The SAM with excellent sphericity was prepared when the paddle was placed on the top of the oil bath. When the paddle was placed at the middle and bottom of the oil bath, some liquid drops aggregated together and formed large aggregations. AGSAM was obtained by grafting the amine groups onto the framework of the silica gel microsphere. The CO 2 adsorption capacity of the AGSAM was 1.04 mmol g -1 with 1% CO 2 at 300 mL min -1 . The AGSAM with 4, 3.2, 2 and 1 mm in diameters had the fluidizing velocities of 0.531, 0.425, 0.265 and 0.159 m s -1 , respectively. The AGSAM with different sizes met different fluidizing conditions.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
FUEL
·
2023
·
IF 7.4
Yiyue Ding,Peng Liu,Xiaoyun Huang,Caili Hu,Zubiao Wen,Zhang-Hui Lu
Liquid sunshine formic acid (FA), which is obtainable through CO 2 hydrogenation with green H 2 or biomass processing, is regarded as a prospective liquid organic hydrogen carrier (LOHC) owing to its high volumetric capacity (53 g H 2 L −1 ), stability, and renewability. The search for effective catalysts to produce H 2 from additive-free FA under ambient conditions is necessary but remains a challenge. Herein, highly dispersed and ultrafine PdAu nanoclusters (NCs) (1.2 nm) anchored by the aminated metal–organic framework (NH 2 -MIL-101) were successfully fabricated using a facile wet-chemical method and employed as a superior catalyst for formic acid dehydrogenation (FAD). The resulting PdAu/NH 2 -MIL-101 catalyst demonstrates 100 % H 2 selectivity and superior performance with a turnover frequency value reaching 2921.0 h −1 at 323 K without any additive. Under similar conditions, this value is higher than the majority of published MOF-based FAD heterogeneous catalysts. The superior performance of PdAu/NH 2 -MIL-101 originates from a synergistic combination of the promoting effect of amino groups, the effective electronic coupling of Pd and Au, and the strong metal-support interaction between PdAu NCs and NH 2 -MIL-101, which promote the formation of reactive PdAu NCs and thus greatly improve catalytic performance. This work may provide important inspiration for developing highly efficient catalysts and strongly promote FA as a promising LOHC for chemical H 2 storage.
研究领域:
催化化学
·
能源化学
·
材料科学
✓ 已验证
DOI
高影响因子
TRANSACTIONS OF TIANJIN UNIVERSITY
·
2018
·Vol. 25
·期 3
·237-244
·
IF 0
Xu Yan,Wang Fan,Hou Qingfeng,Zhao Yujun,Ding Guosheng,Xu Xingguang
In this study, we developed a strategy for using the Scoggins procedure in the synthesis of acetamidines as novel CO 2 -triggered switchable surfactants via acetimidates by effectively tuning the chemical equilibrium. The as-synthesized N ’-alkyl- N , N -diethylacetamidines exhibit excellent CO 2 /N 2 switchability and their bicarbonate salts have the ability to emulsify oil–water mixtures.
研究领域:
化学
·
材料科学
✓ 已验证
DOI
JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART A-TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING
·
2019
·
IF 1.536
Xiaofeng Wang,Beihai Zhou,Xia Shao
Dimethylamine-based pharmaceutical personal care products (DMA-based PPCPs) are a group of N-nitrosodimethylamine (NDMA) precursors. The acid dissociation constant (pKa) values of four DMA-based PPCPs were determined by potentiometric titration over the pH range of 3–11. The pKa values of ranitidine, nizatidine, doxylamine and carbinoxamine corresponding to the DMA moiety were 8.4, 6.8, 9.4 and 9.1, respectively. Competition reaction kinetics and pseudo-first-order reaction kinetics were used to determine the reaction rate constant (k) of the DMA-based PPCPs with O3, NaClO, ClO2 and KMnO4. Comparing the degradation rate constants of the four DMA-based PPCPs, the results of ClO2 oxidation were close, and for the other three oxidants, the order was kranitidine ≈ knizatidine > kdoxylamine ≈ kcarbinoxamine. Comparing the reaction rate of the four oxidants, for ranitidine and nizatidine, the order was kNaClO > kO3 > kKMnO4 > kClO2, and for doxylamine and carbinoxamine, the order was kO3 > kNaClO > kClO2 > kKMnO4.
研究领域:
环境科学
·
化学动力学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）