CHINESE JOURNAL OF CATALYSIS
·
2013
·
IF 1.304
Ming Jin,Dan Zhao,Guozhen He,Yao Tong,Shiqing Han
An efficient method has been developed for the N -arylation of a variety of water-soluble amino alcohols (1.2 mmol) with aryl iodides (1.0 mmol) in water under CuI-catalyzed conditions. The reaction was conducted via substrate-promoted action and did not require an additional ligand or phase-transfer catalyst, and afforded the desired N -aryl amines in acceptable to excellent yields (64%–93%) under mild reaction conditions with a small excess of the amino alcohol.
研究领域:
有机化学
·
合成化学
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2020
·
IF 3.573
Jun Jiang,Teng Li,Kexin Huang,Guangyu Sun,Jing Zheng,Jinlong Chen,Weiran Yang
As a bio-based platform chemical, it is desirable to convert levulinic acid (LA) to varieties of value-added biochemicals. n-Butane, mainly from nonrenewable fossil resources, is a basic chemical to produce some important chemicals, such as butadiene and ethylene. In this paper, 95.5% yield of n-butane was obtained from LA in one-step over base-treated Pt/C at around 300 °C in 4 h. The reaction pathway was confirmed to be the hydrodeoxygenation of LA to valeric acid (VA) and then the VA decarboxylation to n-butane by kinetic studies. Base-treated Pt/C had better reactivity due to its improved decarboxylation activity. Detailed characterization of the catalyst revealed that the Pt particle size is the key reason for the activity improvement, and further studies showed that Pt nanoparticles with a size of 2–4 nm showed the highest decarboxylation activity. This is the first report on the direct conversion of LA to n-butane.
研究领域:
化学工程
·
可再生资源
·
催化科学
✓ 已验证
DOI
高影响因子
Frontiers of Optoelectronics
·
2017
·Vol. 10
·期 2
·132-137
·
IF 0
Jiang Chen,Zhan Honglei,Zhao Kun,Fu Cheng
The terahertz (THz) time-domain spectroscopy technique was used to characterize the cooling process of solid n -alkanes. The THz waveforms of n -octadecane, n -nonadecane, n -eicosane, n -heneicosane, n -docosane, and n -pentacosane were obtained with the cooling time using the aforementioned noncontact optical method. The peak values of the THz signal were found to be related to the cooling temperature of n -alkanes. The THz wave was sensitive to the size and structure of particles in the liquid; therefore, the crystallization process of n -alkanes was monitored. An empirical equation based on signal attenuation was proposed to quantitatively distinguish the content change of structural order in the samples. Results present a new noncontact optical approach for characterizing wax crystallization via THz time-domain spectroscopy.
研究领域:
化学
·
物理学
✓ 已验证
DOI
ACS Sustainable Chemistry & Engineering
·
2021
·
IF 8.198
Shuang Xu,Xiaopo Niu,Gang Yuan,Zheyuan Wang,Shuaikang Zhu,Xiaoxue Li,Yunxi Han,Rong Zhao,Qingfa Wang
Electrocatalytic synthesis of valuable biofuels and chemicals from biomass-derived acids is a promising approach, but selectively producing deoxygenated hydrocarbons is still a great challenge. In this work, we investigated selective electrochemical decarboxylation of n-octanoic acid to produce hydrocarbons (n-tetradecane, n-heptane, and n-heptene) in a single electrolytic cell at room temperature. Pt nanoparticles with different morphologies (nanospheres, nanoflowers, and nanothorns) and further Pt nanothorns with different plane distributions on carbon fiber paper (CFP) were fabricated by a controllable electrodeposition method. The results proved that the Pt(311) plane has the best selectivity and intrinsic activity for decarboxylation products, especially for Kolbe hydrocarbons. The Pt(110) plane shows a similar intrinsic activity as the Pt(311) planes. High selectivity (75%), yield (35%), and Faraday efficiency (34%) for hydrocarbons were achieved over the Pt nanothorn (Pt-NT), which were approximately 1.6, 2.3, and 3.3 times that of Pt nanoflowers, Pt nanospheres, and Pt/C, respectively. The high electrocatalytic activity of Pt nanothorns was attributed to its high electrochemically active surface area (ECSA) and enhanced intrinsic activity derived from the high level of Pt(311) and Pt(110) planes.
研究领域:
能源化学
·
催化科学
·
材料科学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 50
·29668-29674
·
IF 3.119
Shuangxia Wu,Fengjie Geng,Suqin He,Wentao Liu,Hao Liu,Miaoming Huang,Chengshen Zhu
To increase the bioavailability and water solubility of hydrophobic medicine, an amphiphilic block copolymer, polycaprolactone-block-polyhydroxyethyl acrylamide (PCL-b-PHEAA), was synthesized. The copolymer can self-assemble into micelles by dialysis. The micelles were characterized by the Tyndall effect, static drop method, fluorescence spectrometry, dynamic light scattering, scanning electron microscopy and transmission electron microscopy. Ibuprofen was encapsulated inside the micelles by dialysis as a model medicine. The results show that the amphiphilic copolymer forms a uniform micelle system, with spherical micelles dispersed well in solution which have a low critical micelle concentration. In addition, the system shows good amphipathic behavior. Average particle size of a micelle is 104 nm, which increases a lot after drug loading and standing for half a month. In the first few hours, the cumulative release of the drug increases gradually; the rate of increase in the first ten hours is faster, then reaching a plateau which tends to be flat finally. It is similar under two different pH conditions. This biocompatible, biodegradable amphiphilic block copolymer has potential applications in the biomedical field.
研究领域:
生物材料
·
药剂学
·
高分子化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2017
·
IF 4.849
Xiaoxia Wang,Na Li,Zhongfeng Li,Honghua Rao
A dehydrogenative C(sp2)–N bond-forming strategy via copper-catalyzed intramolecular C–H/N–H coupling has been developed, which systematically unraveled the feasibility and practicality for benzoimdazo[1,2-a]indole formations through oxidative anilidic N–H activation. The merit of this strategy is illustrated by the broad tolerance of functionalities, as well as the utilization of extremely cheap copper catalysis to realize potentially useful indole-fused tetracycles in a step- and atom-economical manner.
研究领域:
有机化学
·
药物化学
✓ 已验证
DOI
PubMed
高影响因子
Processes
·
2022
·Vol. 10
·期 7
·1359
·
IF 3.352
Xiaoyu Huo,Chao Jia,Shanshan Shi,Tao Teng,Shaojie Zhou,Mingda Hua,Xiangdong Zhu,Shicheng Zhang,Qunjie Xu
Potassium thiocyanate (KSCN), a highly efficient “three birds with one stone” activator, might work with inorganic activators to produce excellent N/S co-doped porous carbon (NSC) materials for environmental remediation. However, the effects of inorganic activators on cooperative activation are unclear. As a result, the influence of inorganic activators on the synthesis of NSC materials was investigated further. This study shows that the surface areas of the NSC materials acquired through cooperative activation by potassium salts (KOH or K2CO3) were considerably higher than those acquired through KSCN activation alone (1403 m2/g). Furthermore, KSCN could cooperate with K2CO3to prepare samples with excellent specific surface area (2900 m2/g) or N/S content. The as-prepared NSC materials demonstrated higher adsorption capability for chloramphenicol (833 mg/g) and Pb2+(303 mg/g) (pore fitting, complexation). The research provides critical insights into the one-step synthesis of NSC materials with a vast application potential.Keywords:N/S co-doping;porous carbon;chloramphenicol adsorption;Pb2+removal
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2014
·
IF 2.733
Zhenjian Jia,Hongyan Huang,Weixing Zhou,Fei Qi,Meirong Zeng
The pyrolysis mechanism of fuel under supercritical conditions is an important concern for developing regenerative cooling technology of advanced aircraft using hydrocarbon fuel as the primary coolant. n-Decane as a component of some jet fuels was studied at the temperature range from 773 to 943 K in a flow reactor under the pressure of 3, 4, and 5 MPa. Gas chromatograph/mass spectrometry was used to analyze the pyrolysis products, which were mainly alkanes from C1–C9 and alkenes from C2–C9. A kinetic model containing 164 species and 842 reactions has been developed and validated by the experimental results including the distributions of products and the chemical heat sink of fuel. The decomposition pathways of n-decane were illustrated through the reaction flux analysis. It is concluded that the C4–C9 alkanes are mainly generated by the recombinations of alkyls, while the small alkanes (C1–C3) are formed by H-abstraction reactions by C1–C3 alkyl radicals. The applicability at supercritical pressure and high fuel concentration condition of previous models was discussed, and the performance of the present model in reproducing the experimental data is reasonably good.
研究领域:
化学工程
·
航空工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2015
·
IF 5.056
Liang Cheng,Li-Ping Zhu,Pei-Bin Zhang,Jian Sun,Bao-Ku Zhu,You-Yi Xu
Here we demonstrate the tunable molecular selectivities and corresponding mechanisms of poly(N-vinyl imidazole) (PVI) gel-filled membranes prepared by UV initiated graft polymerization of N-vinyl imidazole from ultraporous polysulfone (PSf) substrate. The separation performance was investigated in detail by extensive filtration tests with various organic molecules in water of varying pH and also in salt or ethanol aqueous solution. The variation of membrane water permeability and solute rejection with the feed pH was attributed to the sensitive pore size and charge characteristics of the membranes upon reversible protonation of the confined PVI gel. The separation results discerned three main mechanisms, i.e. size exclusion (sieving), electrostatic repulsion (Donnan exclusion) and adsorption. The rejection of the neutral molecules and the large dye molecules was mostly ascribed to size exclusion, while that of the small charged solutes was dominated by the electrostatic interactions including repulsion for cationic ones and attraction for anionic ones (causing specific adsorption). Typically, at pH 3 the protonated membranes rejected ~90% of the small cationic Vitamin B 1 (VB 1 ) and 100% of the anionic Sunset Yellow (SY) before adsorption saturation, in contrast to less than ~20% rejection of the neutral Vitamin B 2 (VB 2 ) having similar molecule size. In the high concentration salt or ethanol solution the membranes still maintained molecular sieving capability. Most notably, the separations of solute mixtures were indeed achieved, depending on the membrane parameters, the solute characteristics as well as the filtration conditions. The PVI gel-filled membranes developed in this work are promising in some specified or environment-sensitive molecular level separations.
研究领域:
材料科学
·
环境工程
·
化学工程
✓ 已验证
DOI
高影响因子
RSC Advances
·
2021
·Vol. 11
·期 5
·3003-3011
·
IF 3.361
Jian Wang,Cheng Zhang,Xiao-Qing Ye,Wenting Du,Shenxin Zeng,Jian-Hong Xu,Hong Yin
An efficient and practical benzylic aerobic oxidation catalyzed by cheap and simple N-hydroxyimide organocatalyst has been achieved with high yields and broad substrate scope. The organocatalyst used can be recycled and reused by simple workup and only minute amount (1 mol% in most cases) of simple iron salt is used as promoter. Phenyl substrates with mild and strong electron-withdrawing group could also be oxygenated in high yields as well as other benzylic methylenes. Influence of substituents, gram-scale application, catalysts decay and general mechanism of this methodology has also been discussed.
研究领域:
有机化学
·
催化化学
✓ 已验证
DOI
PubMed
高影响因子
TETRAHEDRON
·
2014
·
IF 2.817
Dazhuang Miao,Xuesong Shi,Guozhen He,Yao Tong,Zengqiang Jiang,Shiqing Han
N -(2-Chloro-phenyl)-2-halo-benzamides (halo=I/Br/Cl) as substrates were used for the one-pot synthesis of 2-arylbenzoxazole derivatives via copper-catalyzed intermolecular C–N/intramolecular C–O couplings with primary amines . This aryl amination offers clean reaction conditions and easy work-up in good yields by using CuI as catalyst, readily available 8-hydroxyquinoline as ligand, K 3 PO 4 as base, DMF as solvent.
研究领域:
有机化学
·
合成化学
✓ 已验证
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2013
·
IF 2.505
Zhiqiang Jie,Xiufang Yan,Lianhong Zhao,S.D. Worley,Jie Liang
A novel macroporous cross-linked antimicrobial resin containing quaternarized N-halamine groups, poly(1-chloro-5,5-dimethylhydantoinyl-3-ethyl-p-ethenylphenylmethyl dimethylammonium chloride) (Cl-PSQH), has been synthesized by a facile three-step reaction. The as-prepared resins were characterized by FT-IR, X-ray photoelectron spectroscopy, and zeta-potential measurement. Antimicrobial tests showed that Cl-PSQH was capable of about a 7-log inactivation of Staphylococcus aureus and Escherichia coli O157:H7 within 1 min of contact. Also, its regenerability and preliminary storage stability were investigated.
研究领域:
微生物学
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）