RSC Advances
·
2016
·Vol. 6
·期 19
·15354-15361
·
IF 3.289
Xinhuan Lu,Yang chen,Zhenshuang Zhao,Hao Deng,Dan Zhou,Changcheng Wei,Renfeng Nie,Qinghua Xia
The carbon supported 10% Ni catalysts doped with 3‰ Rh have been prepared by an impregnation method. These catalysts have been used to catalyze the one-step hydrogenation of nitrobenzene to cyclohexylamine. The results show that the 3‰ Rh–10% Ni/CSC (biocarbon) catalyst exhibits an excellent performance to achieve 100 mol% conversion of nitrobenzene and 91.6% selectivity of cyclohexylamine under reaction conditions of 3.5 MPa and 140 °C. The recycling tests reveal recyclable stability of 3‰ Rh–10% Ni/CSC. This catalyst is active for the hydrogenation of a series of electron-deficient nitrobenzenes. Some factors such as the type of carriers, the content of Ni and Rh, the type of metals and additives play important roles in controlling the selective hydrogenation.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2025
·
IF 3.6
Haiyang Wang,Fujun Li,Wenbo Yang,Yuchao Wang,Alexander A. Miskevich,Valery A. Loiko,Lijing Zhang,Shengyang Tao
The mechanistic understanding of how alkylamines impact Ni-metallophotoredox C–N coupling to form diarylamines remains unclear. In this study, 12-alkylamines were evaluated as additives to determine their effects on the synthesis of diarylamines in a flow photochemical system. Notably, n-hexylamine demonstrated the most significant promotional effect. Spectroscopic studies and experimental data reveal n-hexylamine substitutes DABCO as a Ni catalyst ligand, enhancing yields particularly in sterically hindered arylamines.
研究领域:
有机化学
·
合成化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2018
·Vol. 36
·期 12
·1191-1196
·
IF 2.378
Xuefeng Li,Zhe Wang,Shanjun Mao,Yiqing Chen,Minghui Tang,Haoran Li,Yong Wang
Cyclohexylamine is a versatile intermediate in various chemical industries, which can be expediently synthesized via hydrogenation of aniline or nitrobenzene. However, such processes always suffer from side reactions. Many reports have found that specific additives can suppress the formation of side products, but the mechanism is still not clear. In this work, results suggest that it is the hydroxide ion of alkali metal hydroxides, rather than the cations, which plays a key role in suppressing the side reactions on supported Ru-based catalysts. With the assistance of LiOH, the selectivity toward cyclohexylamine increased from 85.4% to 100%. Side products, such as dicyclohexylamine, cyclohexanol and N -isopropyl cyclohexylamine, could no longer be detected. Theoretical calculations further disclosed that addition of alkali metal hydroxides inhibited the dissociation of enamine and decreased the adsorption energy of cyclohexylamine, which might be the reasons for a better selectivity. However, the addition of alkali metal hydroxides reduced the activity of nitrobenzene hydrogenation by unfolding the condensation reaction route. To recover or even further enhance the catalytic performance, a second metal component was introduced and the resultant RuNi/AC exhibited a significant improvement in activity compared with Ru/AC.
研究领域:
化学工程
·
催化科学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2017
·
IF 7.504
Zelun Zhi,Yajuan Su,Yuewei Xi,Liang Tian,Miao Xu,Qianqian Wang,Sara Padidan,Peng Li,Wei Huang
In recent years, microbial colonization on the surface of biomedical implants/devices has become a severe threat to human health. Herein, surface-immobilized guanidine derivative block copolymers create an antimicrobial and antifouling dual-functional coating. We report the preparation of an antimicrobial and antifouling block copolymer by the conjugation of polyhexanide (PHMB) with either allyl glycidyl ether or allyloxy polyethylene glycol (APEG; MW 1200 and 2400). The allyl glycidyl ether modified PHMB (A-PHMB) and allyloxy polyethylene glycol1200/2400 modified PHMB (APEG1200/2400-PHMB) copolymers were grafted onto a silicone rubber surface as a bottlebrush-like coating, respectively, using a plasma-UV-assisted surface-initiated polymerization. Both A-PHMB and APEG1200/2400-PHMB coatings exhibited excellent broad-spectrum antimicrobial properties against Gram-negative/positive bacteria and fungi. The APEG2400-PHMB coating displayed an improved antibiofilm as well as antifouling properties and a long reusable cycle, compared with two other coatings, due to its abundant PEG blocks among those copolymers. Also, the APEG2400-PHMB-coated silicone coupons were biocompatible toward mammalian cells, as revealed by in vitro hemocompatibile and cytotoxic assays. An in vivo study showed a significant decline of Escherichia coli colonies with a 5-log reduction, indicating the APEG2400-PHMB coating surface worked effectively in the rodent subcutaneous infection model. This PHMB-based block copolymer coating is believed to be an effective strategy to prevent biomaterial-associated infections.
研究领域:
生物医学工程
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材料科学
·
微生物学
✓ 已验证
DOI
PubMed
高影响因子
Scientific Reports
·
2017
·Vol. 7
·期 1
·1-11
·
IF 4.259
Lu Xinhuan,He Jie,Jing Run,Tao Peipei,Nie Renfeng,Zhou Dan,Xia Qinghua
Biocarbon supported Ni catalysts have been prepared by facile impregnation of Ni species by microwave-heating and used for selective hydrogenation of nitrobenzene to cyclohexylamine. These catalysts were characterized by X-ray diffraction, Raman spectra, N2 sorption measurement, X-ray photoelectron spectroscopy, temperature programmed reduction of H2 and H2 temperature-programmed desorption. The morphology and particle size of catalysts were imaged by scanning electron microscope and transmission electron microscope. For the hydrogenation of nitrobenzene to cyclohexylamine, 10%Ni/CSC-II(b) exhibits the best catalytic activity to achieve 100 mol% conversion of nitrobenzene and 96.7% selectivity of cyclohexylamine under reaction conditions of 2.0 MPa H2 and 200 °C, ascribed to high dispersion of Ni species and formation of nanosized Ni particles on the support aided by microwave-heating. Thus-prepared Ni/CSC catalyst is greatly activated, in which the addition of precious metal like Rh is totally avoided.
研究领域:
催化化学
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材料科学
✓ 已验证
DOI
PubMed
高影响因子
WATER SCIENCE AND TECHNOLOGY
·
2021
·Vol. 83
·期 9
·2160-2168
·
IF 1.915
Feng Kaiqing,Zhang Jiandong,Gao Lili,Tian Qi
Alicyclic amines are widely used in several types of industries, and considerable attention has been devoted to possible environmental pollution by alicyclic amines in hypersaline industrial wastewater. In this study, a new hypersaline tolerant bacterial TYUT067 capable of growing in liquid basal salt medium with cyclohexylamine (CHAM) as the sole carbon source and energy source, was isolated from soil, and discovered with highly efficient CHAM degrading ability. The strain TYUT067 was identified as Paenarthrobacter sp. based on 16S rDNA gene sequence, and its degradation characteristic was examined. The results revealed that the isolated TYUT067 could grow well under pH range of 6.5–10.0, temperature from 20 °C to 30 °C. For degradation of 60 mM of cyclohexylamine, 100% degradation could be finished within 120 h. The TYUT067 could degrade 10 mM CHAM under hypersaline conditions (3–5% NaCl, w/v), revealed the hypersaline tolerance of TYUT067. Different type of amines was also tested with TYUT067, the degradations of >90% were achieved toward several alicyclic amines. The current results suggested that TYUT067 was a potential species could be efficiently used for the degradation of alicyclic amines and might be applicable to a hypersaline wastewater treatment system for the removal of alicyclic amines. A new cyclohexylamine degradation bacterial strain TYUT067 was isolated from soil environment. The isolated TYUT067 is an alkali-tolerant strain and mesophilic microorganisms. The isolated TYUT067 can degrade CHAM under hypersaline environment. The isolated TYUT067 can degrade various alicyclic amines.
研究领域:
环境微生物学
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环境工程
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生物降解
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工业废水处理
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污染生态学
✓ 已验证
DOI
高影响因子
Nature Protocols
·
2024
·
IF 13.1
Wu Yueming,Chen Kang,Wang Jiangzhou,Dai Wenhui,Yu Haowen,Xie Xinyi,Chen Minzhang,Liu Runhui
Synthetic polypeptides, also known as poly(α-amino acids), have the same polyamide backbone structures as natural proteins and peptides. As an important class of biomaterials, polypeptides have been widely used because of their biocompatibility, bioactivity and biodegradability. Ring-opening polymerization of N -carboxyanhydride (NCA) is a classical and widely used method for the synthesis of polypeptides. The dominantly used primary amine–initiated NCA polymerization can yield well-defined polymers and complex macromolecular architectures, but the reaction is slow and sensitive to moisture, making it necessary to use anhydrous solvents and a glovebox. One solution is to use lithium hexamethyldisilazide (LiHMDS) as the initiator, as described in this protocol. LiHMDS-initiated NCA polymerization is less sensitive to moisture and can be carried out in an open vessel outside the glovebox. It is also very fast; the reaction can be complete within 5 min to produce 30-mer polypeptides. In this protocol, poly(γ-benzyl- l -glutamate) is prepared as an example, but the protocol can easily be adapted to the synthesis of other polypeptides by generating NCAs from different amino acids, making it particularly suitable for the efficient parallel synthesis of polypeptide libraries. We provide detailed procedures for NCA synthesis and purification, the method of polymer end-group modification and measurement of polymerization kinetics and reactivity ratio. The procedure for synthesis of monomers and polymerization to form polypeptides requires <1 d. The superfast and open-vessel NCA polymerization method described here will probably enable a wide range of applications in the synthesis and functional study of polypeptide biomaterials.
研究领域:
生物化学
·
高分子化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Jiale Wu,Jiajun Zhang,Liguo Wang,Ziqiang Han,Xiang Hui,Yan Cao,Jianhui Shi,Shuang Xu,Peng He,Huiquan Li
Green production of alicyclic amines is highly desirable but of great challenges. Herein, an efficient one-pot synthesis of alicyclic amines from nitroaromatics was realized with a Pt-Ru bimetallic catalyst. 0.5 %Pt-2.5 %Ru supported on an air-exfoliated C 3 N 4 nanosheet achieved 100.0 % conversion of nitrobenzene (NB) with 98.9 % selectivity of cyclohexylamine (CHA) under mild conditions of 80 °C and 1 MPa, attaining a yield rate for alicyclic amine of 357.9 mmol/g metal ·h. Our study has shown hydrogenation of nitro group and aromatic ring took place in sequence over Pt and Ru in a tandem manner due to the highly selective adsorption. During the hydrogenation, the homolytic dissociation of H 2 occurred on the bimetal sites and the inter-site hydrogen spillover between the bimetal played a crucial role. C 3 N 4 nanosheet as the support not only gave rise to the uniform dispersion of metal nanoparticles, but was crucial in curbing the unnecessary adsorption of intermediate aromatic amines. Our study has also demonstrated the good stability and wide applicability of the Pt-Ru/C 3 N 4 -air catalyst for the hydrogenation of various nitroaromatic derivatives.
研究领域:
催化化学
·
绿色化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2019
·
IF 2.29
Jian Wang,Yongqin Du,Cunbin Du,Anli Xu,Ganbing Yao,Hongkun Zhao,Xuedong Zhu,Xuhong Guo
For switchable hydrophilicity solvent (SHS) systems ( N,N -Dimethylcyclohexylamine (DMCA), water, and carbon dioxide): the density, viscosity, refractive index and conductivity at (283.15–308.15) K and 0.1 Mpa, were measured. The apparent molar volumes were determined as a function of composition at each temperature from experimental data. Based on Masson’s equation limiting apparent molar volumes and Masson’s coefficient S V describing the character of interactions were calculated. The relative viscosity values were adjusted to obtain the viscosity B coefficients and dB/dT values. It has been observed that there exist strong solute-solvent and solute-solute interactions in these systems, and DMCAH-bicarbonate salt acts as structure-maker in aqueous solvent.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2019
·
IF 2.29
Dan Zhao,Yun Zhuang,Chunshan Fan,Fang Yang,Yuhuan Chen,Xihui Zhang
Surface tension ( γ ) for five binary mixtures containing N, N-dimethylcyclohexylamine (DMCA) and alcohol, ethanol, n-propanol, iso -propanol, n-butanol or iso -butanol were measured over the whole range of composition at 0.1 MPa and different temperatures ranging from (288.15 to 308.15) K. From the experimental data, the surface tension deviations ( δγ ) for the binary mixtures were calculated. The δγ values are positive for all the studied systems and increase with the decreasing of alky chain length of alcohol. For the mixture containing the branched alkyl alcohol, the increase is significant compared with the equivalent molecules with straight chains. According to temperature dependence of surface tension, the thermodynamic parameters, surface enthalpy ( H γ ) and surface entropy ( S γ ) were also estimated and further discussed.
研究领域:
物理化学
·
热力学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER COMPOSITES
·
2016
·Vol. 39
·期 2
·448-456
·
IF 2.004
Bing Xue,Huimin Wang,Maosheng Xia,Xingyuan Wang,Kuo Yang,Qianwen Chi,Fangfei Li,Yinshan Jiang
Nacrite nanorolls were prepared by the delamination and rolling of the platy nacrite particles and the nacrite nanorolls were melt-compounded with LLDPE to prepare a novel Nacrite/LLDPE composite. In this method, hexylamine was intercalated into the interlayer space of methoxy-modified nacrite precursor and the deintercalation of nacrite-hexylamine intercalation complex in toluene resulted in the delamination and rolling of nacrite layers. The nacrite nanorolls were composed with linear low-density polyethylene (LLDPE) to prepare a novel Nacrite/LLDPE composite. X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and N 2 adsorption–desorption test were used to evaluate the prepared nacrite nanorolls. The results showed that the interlayer octahedral surface of nacrite was grafted with methanol and the methoxy-modified nacrite was intercalated with hexylamine. The deintercalation of nacrite-hexylamine intercalation complex in toluene disturbed the orderly arrangement of nacrite layers, leading to a delamination of the layered particles and subsequent formation of aluminosilicate nanorolls. The specific surface area (SSA) and V por value of nacrite nanorolls reached 34.69 m 2 /g and 0.22 cm 3 /g (4.52 m 2 /g and 0.13 cm 3 /g for raw nacrite). Furthermore, the mechanical properties test confirmed that the introduction of nacrite nanorolls into LLDPE matrix could improve the tensile and tear strength. 6.4% and 6.8% higher tensile strength than the pure LLDPE were observed for Nacrite/LLDPE composite with 2 wt% and 4 wt% nacrite nanorolls filler. POLYM. COMPOS., 39:448–456, 2018. © 2016 Society of Plastics Engineers
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2020
·
IF 2.369
Dan Zhao,Yun Zhuang,Chunshan Fan,Xihui Zhang,Fang Yang,Yuhuan Chen
The densities of six binary systems containing N,N-dimethylcyclohexylamine (DMCA) and ethanol, n-propanol, iso-propanol, n-butanol, iso-butanol, or tert-butanol were reported in this work at temperatures ranging from (288.15 to 318.15) K and atmospheric pressure. According to the experimental density values, molar volume (Vm), thermal expansion coefficient (αp), and excess molar volume (VmE) were calculated. The results showed that VmE values were all negative over the entire composition. The minimum values of the six systems at 298.15 K were located at (−1.097, −1.094, −0.900, −1.033, −1.154, and −1.073) cm3·mol–1 at about xDMCA = 0.4, respectively. All these are dependent on intermolecular interactions and the steric structural effect. Furthermore, VmE variations with composition (xDMCA) as well as temperature were well fitted with the Redlich–Kister-type polynomial equation.
研究领域:
物理化学
·
热力学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）