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Study on a green synthesis of

Aixin WANG, Yuanbin SHE, Jing FAN

《化学科学与工程前沿(英文)》 2009年 第3卷 第2期   页码 219-221 doi: 10.1007/s11705-009-0058-z

摘要: A novel method for the synthesis of -oxo-bis[tetraarylporphyrinatoiron] ([TRPPFe] O) based on the reaction between tetraarylporphyrinironchloride (TRPPFeCl) and H O in toluene was investigated in this paper. Three kinds of [TRPPFe] O were synthesized by this novel synthetic method, and their structures were characterized by elemental analysis, IR spectra and UV-Vis spectroscopy.

关键词: μ-oxo-bis[tetraarylphenylporphinatoiron]     green synthesis     water    

Boehmite-supported CuO as a catalyst for catalytic transfer hydrogenation of 5-hydroxymethylfurfural to 2,5-bis

《化学科学与工程前沿(英文)》 2023年 第17卷 第4期   页码 415-424 doi: 10.1007/s11705-022-2225-4

摘要: 2,5-bis(hydroxymethyl)furan (BHMF) is an important monomer of polyester. Its oxygen-containing rigid ring structure and symmetrical diol functional group establish it as an alternative to petroleum-based monomer with unique advantages for the prodution of the degradable bio-based polyester materials. Herein, we prepared a boehmite-supported copper-oxide catalyst for the selective hydrogenation of 5-hydroxymethylfurfural into BHMF via catalytic transfer hydrogenation (CTH). Further, ethanol successfully replaced conventional high-pressure hydrogen as the hydrogen donor, with up to 96.9% BHMF selectivity achieved under suitable conditions. Through characterization and factor investigations, it was noted that CuO is crucial for high BHMF selectivity. Furthermore, kinetic studies revealed a higher by-product activation energy compared to that of BHMF, which explained the influence of reaction temperature on product distribution. To establish the catalyst structure-activity correlation, a possible mechanism was proposed. The copper-oxide catalyst deactivated following CTH because ethanol reduced the CuO, which consequently decreased the active sites. Finally, calcination of the catalyst in air recovered its activity. These results will have a positive impact on hydrogenation processes in the biomass industry.

关键词: biomass     5-hydroxymethylfurfural     2     5-bis(hydroxymethyl)furan     transfer hydrogenation     catalysis    

Synthesis of mono and bis-4-methylpiperidiniummethyl-urea as corrosion inhibitors for steel in acidic

Abbas TEIMOURI, Nasrin SOLTANI, Alireza Najafi CHERMAHINI

《化学科学与工程前沿(英文)》 2011年 第5卷 第1期   页码 43-50 doi: 10.1007/s11705-010-0532-7

摘要: Mono and bis-4-methylpiperidiniummethyl urea were synthesized, characterized and used as new corrosion inhibitors of mild steel in the acidic media. Inhibitory effect of two compounds on mild steel surface in the 1 mol·L sulphuric acid has been studied by a series of techniques, such as potentiodynamic polarization, weight loss and quantum chemical calculation methods. Potentiodynamic polarization measurements showed that two inhibitors are mixed type. All measurements showed that inhibition efficiencies enhanced with increase of inhibitor concentration. This reveals that inhibitive actions of inhibitors were mainly due to adsorption on mild steel surface. Density functional (DFT) calculations have been carried out for the title compounds by performing HF and DFT levels of theory using the standard 6-31G* basis set.

关键词: corrosion inhibitors     mild steel     acidic medium     theoretical studies     DFT    

Synthesis and characterization of biodegradable thermoplastic elastomers derived from N′,N-bis (2-carboxyethyl

Jiaojiao Shang, Guo Yao, Ronghui Guo, Wei Zheng, Long Gu, Jianwu Lan

《化学科学与工程前沿(英文)》 2018年 第12卷 第3期   页码 457-466 doi: 10.1007/s11705-018-1716-9

摘要:

Biodegradable poly(ether-imide-ester) elastomers were synthesized from succinic acid, 1,4-butanediol, polyethylene glycol 1000 and N′,N-bis(2-carboxyethyl)-pyromellitimide which was derived from pyromellitic dianhydride and glycine. The chemical structures, crystallinities, thermal stabilities, mechanical properties, hydrophilicities and biodegradabilities of these elastomers were investigated. The hard segments of the linear aliphatic poly(ether-ester) exhibited monoclinic chain packing. Increasing the amount of aromatic bisimide moieties in the poly(ether-ester) reduced the crystallinity of the material and improved the thermal stability and tensile strength of the elastomers. In addition, introducing a suitable amount of aromatic bisimide moieties into the poly(ether-ester) backbones endowed the elastomers with improved biodegradability but too many aromatic bisimide groups reduced the biodegradability of the elastomers.

关键词: thermoplastic elastomers     biodegradability     thermo-stability     mechanical property     aromatic bisimide moiety    

Polymerization of methyl methacrylate catalyzed by mono-/bis-salicylaldiminato nickel(II) complexes and

Jihong LU, Danfeng ZHANG, Qian CHEN, Buwei YU

《化学科学与工程前沿(英文)》 2011年 第5卷 第1期   页码 19-25 doi: 10.1007/s11705-010-0546-1

摘要: Two types of salicylaldiminato-based nickel complexes, mono-ligated Ni(II) complexes ([O-C H - - C(H)=N-Ar]Ni(PPh )(Ph) ( ), [O-(3,5-Br )C H - -C(H)=N-Ar]Ni(PPh )(Ph) ( ), [O-(3- -Bu)C H - -C(H)=N-Ar]Ni(PPh )(Ph) ( )) and bis-ligated Ni(II) complexes ([O-(3,5-Br )C H - -C(H)=N-Ar] Ni ( ), [O-(3,5-Br )C H - -C(H)=N-2-C H (PhO)] Ni ( ), Ar=2,6-C H ( -Pr) ) were synthesized and characterized by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), mass spectrography (MS) and elemental analysis (EA). In the presence of methylaluminoxane (MAO) as cocatalyst, all the nickel complexes exhibited high activities for the polymerization of methyl methacrylate (MMA) and syndiotactic-rich poly(methyl methacrylate) (PMMA) was obtained. The complexes with less bulky substituents on salicylaldiminato framework possessed higher activities, while with the same salicylaldiminato, the mono-ligated nickel complexes showed higher catalytic activity than bis-ligated ones.

关键词: late transition metal catalyst     methyl methacrylate     polymerization     salicylaldiminato nickel complexes     methylaluminoxane     syndiotactic structure    

Product identification and toxicity change during oxidation of methotrexate by ferrate and permanganate in water

《环境科学与工程前沿(英文)》 2022年 第16卷 第7期 doi: 10.1007/s11783-021-1501-8

摘要:

• Oxidation of methotrexate by high-valent metal-oxo species was first explored.

关键词: Anticancer drugs     High-valent metal-oxo species     Oxidation kinetics     Reaction mechanisms     Multi-endpoint toxicity    

Synthesis and characterization of 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles with two-photon fluorescence

ZHU Xiaoqin, QIAN Ying, LU Zhifeng

《化学科学与工程前沿(英文)》 2007年 第1卷 第4期   页码 381-384 doi: 10.1007/s11705-007-0069-6

摘要: Four novel 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles that exhibit strong two-photon absorption and enhanced two-photon excited fluorescence were designed and synthesized based on push-core-pull-core-push molecules built from embedding electron-transporting 1,3,4-oxadiazole in aromatic conjugated system through Wittig-Horner reaction. Their chemical structures were determined to show trans-vinylene character according to infrared (IR) and H nuclear magnetic resonance (NMR) spectra. A very effective energy transfer from the excited units to the ?-conjugated bridging unit can enhance the two-photon absorption and two-photon fluorescence.

关键词: 2-arylvinyl     trans-vinylene character     effective     fluorescence     push-core-pull-core-push    

Phytotoxicity in seven higher plant species exposed to di-

Tingting MA,Ying TENG,Peter CHRISTIE,Yongming LUO

《环境科学与工程前沿(英文)》 2015年 第9卷 第2期   页码 259-268 doi: 10.1007/s11783-014-0652-2

摘要: We investigated phytotoxicity in seven plant species exposed to a range of concentrations (0– 500 mg·kg soil) of di- -butyl phthalate (DnBP) or bis (2-ethylhexyl) phthalate (DEHP), two representative phthalate esters (PAEs) nominated by USEPA as priority pollutants and known environmental estrogens. We studied seed germination, root elongation, seedling growth, biomass (fresh weight, FW) and malondialdehyde (MDA) content of shoots and roots of wheat ( L.), alfalfa ( L.), perennial ryegrass ( ), radish ( L.), cucumber ( L.), oat ( ) and onion ( L.), together with monitoring of plant pigment content (chlorophyll a, b and carotinoids) in alfalfa, radish and onion shoots. Root elongation, seedling growth and biomass of the test species were generally inhibited by DnBP but not by DEHP, indicating a lower level of phytotoxicity of DEHP than of DnBP. MDA contents of four species were promoted by PAE exposure, but not in alfalfa, ryegrass or onion shoots, indicating lower sensitivity of these three species to PAE pollutants. Plant pigment contents were clearly affected under the stress of both pollutants, implying the potential damage to the photosynthetic system of test plants, mainly by decreasing the content of chlorophyll a and b. Results of DnBP and DEHP phytotoxicity to the primary growth of test plants has provided information for the assessment of their environmental risk in the soil and also forms a basis for the further analysis of their toxic effects over the whole growth period of different plant species.

关键词: phytotoxicity     di-n-butyl phthalate     bis(2-ethylhexyl) phthalate     malondialdehyde     plant pigments (chlorophyll a     b and carotinoids)    

标题 作者 时间 类型 操作

Study on a green synthesis of

Aixin WANG, Yuanbin SHE, Jing FAN

期刊论文

Boehmite-supported CuO as a catalyst for catalytic transfer hydrogenation of 5-hydroxymethylfurfural to 2,5-bis

期刊论文

Synthesis of mono and bis-4-methylpiperidiniummethyl-urea as corrosion inhibitors for steel in acidic

Abbas TEIMOURI, Nasrin SOLTANI, Alireza Najafi CHERMAHINI

期刊论文

Synthesis and characterization of biodegradable thermoplastic elastomers derived from N′,N-bis (2-carboxyethyl

Jiaojiao Shang, Guo Yao, Ronghui Guo, Wei Zheng, Long Gu, Jianwu Lan

期刊论文

Polymerization of methyl methacrylate catalyzed by mono-/bis-salicylaldiminato nickel(II) complexes and

Jihong LU, Danfeng ZHANG, Qian CHEN, Buwei YU

期刊论文

Product identification and toxicity change during oxidation of methotrexate by ferrate and permanganate in water

期刊论文

Synthesis and characterization of 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles with two-photon fluorescence

ZHU Xiaoqin, QIAN Ying, LU Zhifeng

期刊论文

Phytotoxicity in seven higher plant species exposed to di-

Tingting MA,Ying TENG,Peter CHRISTIE,Yongming LUO

期刊论文