JOURNAL OF APPLIED MICROBIOLOGY
·
2019
·Vol. 126
·期 1
·127-137
·
IF 2.683
Zhang H.‐L.,Zhang C.,Pei C.‐H.,Han M.‐N.,Li W.
AimsWe aimed to explore Yarrowia lipolytica carbonyl reductases as effective biocatalysts and to develop efficient asymmetric reduction systems for chiral alcohol synthesis.Methods and ResultsYarrowia lipolytica carbonyl reductase genes were obtained via homologous sequence amplification strategy. Two carbonyl reductases, YaCRI and YaCRII, were identified and characterized, and used to catalyse the conversion of 2‐hydroxyacetophenone (2‐HAP) to optically pure (S)‐1‐phenyl‐1,2‐ethanediol. Enzymatic assays revealed that YaCRI and YaCRII exhibited specific activities of 6·96 U mg−1 (99·8% e.e.) and 7·85 U mg−1 (99·9% e.e.), respectively, and showed moderate heat resistance at 40–50°C and acid tolerance at pH 5·0–6·0. An efficient whole‐cell two‐phase system was established using reductase‐expressing recombinant Escherichia coli. The conversion of 2‐HAP (20·0 g l−1) conversion with the solvent of dibutyl phthalate was approximately 70‐fold higher than in water. Furthermore, the two recombinant E. coli displayed biocatalyst activity and enantioselectivity towards several different carbonyl compounds, and E. coli BL21 (DE3)/pET‐28a‐yacrII showed a broad substrate spectrum.ConclusionsA new whole‐cell recombinant E. coli‐based bioreduction system for enantiopure alcohol synthesis with high enantioselectivity at high substrate concentrations was developed.Significance and Impact of the StudyWe proposed a promising approach for the efficient preparation of enantiopure chiral alcohols.
研究领域:
生物化学
·
生物技术
·
酶学
✓ 已验证
DOI
PubMed
高影响因子
Nano Energy
·
2020
·
IF 16.602
Qingyan Zhou,Zhen Zhang,Jiajun Cai,Bing Liu,Yunlong Zhang,Xiaofei Gong,Xulei Sui,Aiping Yu,Lei Zhao,Zhenbo Wang,Zhongwei Chen
Rational design and construction of highly efficient and durable non-noble-metal bifunctional catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is crucial to promote the widespread implementation of rechargeable Zn-air batteries. Herein, a bifunctional catalyst comprising Co nanoparticles uniformly embedded in hollow nitrogen doped carbon tubes (Co@hNCTs) is fabricated by a facile tube-directed templating strategy. In this strategy, surfactant-treated polypyrrole (PPy) nanotubes serve as the structure-guiding templates for efficient capture of Co 2+ , realizing the in-situ growth of zeolitic imidazolate frameworks-67 (ZIF-67) nanocrystals on PPy nanotubes . Sodium laurylsulfonate acts as anionic surfactant to endow PPy nanotubes with functional electronegative surface and strong anchoring effect toward ZIF-67, playing the pivotal role in binding of ZIF-67 nanocrystals with PPy nanotubes potently. Consequently, the developed catalyst presents a superior ORR activity with the half-wave potential of 0.87 V excellent durability with only a 7 mV loss of half-wave potential after 5000 cycles. The catalyst also exhibits superior catalytic performance for OER. When serving as an air electrode in Zn-air batteries, a large power density of 149 mW cm −2 and long-term cyclability for over 500 h are realized in ambient air, implying the great potential in practical application.
研究领域:
材料科学
·
电化学
·
能源存储
·
催化化学
·
纳米材料
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Pan Liu,Jiguang Liu,Jiahui Liu,Xia Dong,Rui Wang
Using nitrogen, the morphological evolution of iron oxide/alkoxide particles was investigated by altering the reaction temperature in a one-pot solvothermal synthesis , resulting in a series of particles with different shapes, such as smooth sheet-like, rough sheet-like and cubic particles. The particle shape began to transform at 180 °C due to the altered crystallization and compositions, accompanied by the evolution of the magnetic properties without post-calcination. Based on the above research, large flower-like particles could be prepared by a two-step heating process. In virtue of the structural and morphological advantages, the flower-like particles were applied in fabricating a superwetting surface.
研究领域:
材料化学
·
纳米科技
·
表面科学
·
功能材料
·
物理化学
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2024
·
IF 4.8
Guojun Lv,Xuyang Zou,Yan Chen,Qing Zhang,Xubin Zhang,Fumin Wang
The successful one-pot synthesis of MCM-41/MFI composite is mainly concentrated on the trivalent heteroatom of Al 3+ and Fe 3+ , however there are almost no reports about the one-pot synthesis of Ti-MCM-41/MFI composite. In this work, we reported the one-pot synthesis of Ti-MCM-41/MFI composite with a temperature-gradient hydrothermal strategy using hexadecyl trimethylammonium bromide CTAB and silicalite-1 seed as structure directing agents as well as ammonia solution as alkali source, and its application as heterogeneous catalyst in the cyclohexene epoxidation reactions. The impact of Si/Ti molar ratio and ammonia dosage as well as CTAB amount on the formation and property of Ti-MCM-41/MFI composite were systematically investigated. In addition, a possible partial transformation mechanism of Ti-MCM-41/MFI composite sample was proposed. The synthesized Ti-HMZ-50-N3.77-Se0.05 sample with ordered mesoporous structure and high content of framework titanium active centers revealed the eminent cyclohexene epoxidation performance, achieving a 32.51 % of cyclohexene conversion and a 61.27 % selectivity of cyclohexene oxide within 5 h of reaction.
研究领域:
催化化学
·
材料化学
·
纳米材料
·
多相催化
·
绿色化学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2015
·
IF 6.217
Zhantao Liu,Xusong Qin,Hui Xu,Guohua Chen
In this study, a one-pot sintering process incorporating sol–gel preparation route and in-situ carbon coating was proposed for the synthesis of carbon-coated nanosized LiTi 2 (PO 4 ) 3 . Experimental results show that the prepared LiTi 2 (PO 4 ) 3 particles are of high crystallinity and well-coated by turbostratic carbon. Attributed to nanosized particles and enhanced conductivity provided by turbostratic carbon coating, the carbon-coated LiTi 2 (PO 4 ) 3 showed high rate performance and good cycling life in aqueous electrolyte. Particularly, the carbon-coated LiTi 2 (PO 4 ) 3 exhibited initial specific capacities of 103 and 89 mAh g −1 , and retained 80.6% and 97% of the initial capacities after 120 cycles at 1C and 10C in aqueous electrolyte, respectively. The high rate performance and good cycling life of carbon-coated LiTi 2 (PO 4 ) 3 in aqueous electrolyte reveal its potential as negative electrode in aqueous lithium-ion batteries for electric vehicles and industrial-scale energy storage systems .
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米技术
·
无机化学
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2016
·
IF 4.758
Yong Zhang,Tianyi Han,Ziying Wang,Chen Zhao,Jianning Li,Teng Fei,Sen Liu,Geyu Lu,Tong Zhang
Herein, a novel electrochemical hydrazine sensor has been successfully fabricated using N-doped carbon film-immobilized Au nanoparticles coated ZnO jungle on indium tin oxide (AuNPs@NC-ZnO/ITO) as working electrode. The AuNPs@NC-ZnO/ITO has been prepared by an in situ synthesis method through the following steps. Firstly, the ZnO jungle modified ITO was prepared by electrochemical deposition method. Then, zeolitic imidazolate framework-8 (ZIF-8) film was formed on the surface of ZnO jungle by wet-chemical method using ZnO jungle and 2-methylimidazole as Zn precursor and organic ligand, respectively. The loading AuNPs was performed by adsorption of Au 3+ into micropores of ZIF-8, followed by heat treatment under N 2 atmosphere, where the ZIF-8 converted into N-doped carbon and Au 3+ converted into AuNPs embedded in N-doped carbon film. Most importantly, such AuNPs@NC-ZnO/ITO exhibited good electrocatalytic activity for the oxidation of hydrazine. The hydrazine sensor based on AuNPs@NC-ZnO/ITO showed linear detection range from 0.05 to 10 μM and detection limit of 4.1 nM at a signal-to-noise ratio of 3.
研究领域:
分析化学
·
电化学传感
·
纳米材料
·
生物医学工程
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环境监测
·
转化医学
✓ 已验证
DOI
高影响因子
Nano Select
·
2021
·Vol. 2
·期 11
·2135-2147
·
IF 0
Puhong Wen,Xiaowen Jiang,Qian He,Dengwei Hu,Lijun Ren,Weixing Zhao
The tetragonal phase Nb 2 O 5 (T-Nb 2 O 5 ) nanobelts with preferentially exposed the (010) facet have been successfully prepared for the first time by insitu topological reaction using the KNb 3 O 8 nanobelts as the precursor. Meanwhile, the transformation mechanism of the crystal structure and morphology from the layered KNb 3 O 8 nanobelt to the T-Nb 2 O 5 nanobelt was revealed in detail by using XRD, FE-SEM, TEM, HRTEM, SAED, UV-vis DRS, EDX, XPS, and Raman spectra. In addition, Ag deposited T-Nb 2 O 5 (Ag/T-Nb 2 O 5 ) nanobelts were prepared by photo-reduction reaction. The photoelectrochemical properties of the T-Nb 2 O 5 nanobelts and Ag/T-Nb 2 O 5 nanobelts as a photocatalyst were evaluated by splitting water under simulated sunlight. The results show that the photocurrent density generated by the prepared Ag/T-Nb 2 O 5 sample is 48.1 µA∙cm −2 , which is 2.3 times that of the T-Nb 2 O 5 sample, and the prepared tetragonal phase T-Nb 2 O 5 nanobelts produce a photocurrent value 1.5 times that of the contrast orthogonal phase O-Nb 2 O 5 nanosheets. It indicates that the (010) facet of the tetragonal phase Nb 2 O 5 is one of the highest photocatalytic active surfaces, and the visible light utilization efficiency of the T-Nb 2 O 5 nanobelt with Ag deposited on the surface has been significantly improved, which implies that it has potential applications in the field of photocatalysis.
研究领域:
材料科学
·
纳米科技
·
光催化
·
能源化学
·
半导体材料
·
表面科学
✓ 已验证
DOI
RSC Advances
·
2016
·Vol. 6
·期 62
·57009-57012
·
IF 3.289
Di Wu,Jing Ye,Lie Chen,Yongzheng Wang,Kai Fang,Mingjiang Xie,Luming Peng,Xuefeng Guo,Weiping Ding
Crystalline mesoporous γ-Fe2O3 with a high surface area was prepared by a novel solvent-free route. This material exhibits a high reversible capacity with superior cycle performance and an exceptional high-rate capability as an anode material for Li-ion batteries.
研究领域:
材料科学
·
电化学
·
纳米材料
·
能源存储
·
固体化学
·
电池技术
✓ 已验证
DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2022
·Vol. 33
·期 11
·103807
·
IF 4.969
Jingxi Zhang,Yifan Niu,Yu Zhou,Shaohua Ju,Yongwan Gu
In this study, green tea was used as a reducing agent to prepare GT-nZVI/Cu nano-zero-valent iron-copper bimetallic materials for nitrate degradation. Through single factor experiments, the process conditions for nitrate removal by GT-nZVI/Cu were optimized. By measuring the contents of nitrate, nitrite, and ammonia nitrogen in the reaction products, the reduction pathway of nitrate-nitrogen in GT-nZVI/Cu was studied. In addition, the removal mechanism of nitrate by GT-nZVI/Cu was also analyzed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and kinetic experiments. The results showed that the size of GT-nZVI/Cu particles is between 50 and 70 nm, and they are irregular spherical shapes. The polyphenol antioxidants in green tea make GT-nZVI/Cu have stronger antioxidant properties, and the denitration products are mostly nitrogen. The addition of copper ions accelerates the reaction time and reaction rate. The maximum removal rate of nitrate by GT-nZVI/Cu within 75 min can be up to 99 %. After three repeated experiments, the removal rate of GT-nZVI/Cu can still reach 70 %. The removal mechanism of GT-nZVI/Cu has enhanced nitrate removal through complexation, redox, and adsorption co-precipitation. This study provides a new route for the green preparation and efficient application of nZVI.
研究领域:
环境化学
·
纳米材料科学
·
水处理技术
·
环境功能材料
·
污染控制化学
·
应用催化
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2014
·Vol. 132
·期 7
·
IF 1.64
Pan Dongdong,Tian Hengshui
Soluble and thermally stable polycarbonate polyurethane elastomers were synthesized through a solvent-free and nonisocyanate melt transesterification process. The conditions of this process were studied, and the optimum conditions were as follows: the catalyst dibutyltin oxide dosage was 0.125 wt %, the raw material molar ( n ) ratio of dimethyl 1,6-hexamethylene dicarbamate (HDC) to poly(carbonate macrodiol) (PCDL) was n (HDC)/ n (PCDL) = 1:0.99, the reactants were prepolymerized under 100°C for 1 h and then under 185°C and a high vacuum for 4 h. Three different PCDLs were selected to participate in the reaction under the conditions mentioned previously, and their structures were characterized by Fourier transform infrared spectroscopy and X-ray diffraction. The products obtained from this process were still stable under 280°C. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 41377.
研究领域:
高分子化学
·
生物材料
·
聚合物科学
·
材料化学
·
医用高分子
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
·
2024
·
IF 3.8
Zhi Yang,Shufang Ma,Yu Shi,Xiaodong Hao,Lin Shang,Bin Han,Bocang Qiu,Bingshe Xu
Nanowires (NWs)-based heterojunction photodetectors (PDs) have been widely applied in the fields of remote sensing, night vision, environmental monitoring, and optical communications with high light absorption coefficient and photoelectric conversion efficiency. Here, S-GaAs NWs/Si heterojunction was developed to form a broadband self-powered PDs by growing GaAs NWs on Si substrate through the sulfur-catalyzed assisted chemical vapor deposition (CVD) technology. Compared with the pure GaAs NWs, the sulfur-assisted catalysts could not only inhibit Ostwald ripening of Au seeds to improve the crystalline quality of NWs but also form a thin Ga–S bond passivation layer to reduce surface defects and enhance the optoelectronic performance of the PDs. The fabricated GaAs NWs/Si heterojunction PDs exhibit excellent performances with the large responsivity of 10.3 mA W −1 and high detectivity of 9.59 × 10 12 cm Hz 1/2 W −1 . Additionally, the designed PDs have the broadband wavelength photoresponse from visible to near infrared and fast response speed (rise/fall time of 3.8/21.8 ms). Importantly, the develop strategy of hybrid heterojunction PDs can be extended to other semiconductor materials for facilitating the practical application of high-performance optoelectronic devices .
研究领域:
半导体材料
·
纳米电子学
·
光电子学
·
凝聚态物理
·
功能材料
·
器件物理
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Yuhua Dong,Jianbin Zheng
The work presented that by regulating the proportion between cobalt and 2-methylimidazole in distilled water, a series of Co-based imidazolate framework compounds with diverse shapes were synthesized at ambient temperature. The morphology and structural characteristics of the compounds were surveyed by scanning electron microscope, energy disperse spectra, powder X-ray diffraction and N 2 absorption-desorption. It was found by cyclic voltammetry that the zeolitic imidazolate framework compound synthesized at a ratio of 1:20 had the best electrocatalytic activity to H 2 O 2 reduction, therefore, the compound was chosen to fabricate a H 2 O 2 electrochemical sensor. Electrochemical studies indicated that the sensor had a determination limit of 0.7 μM and short response time within 3 s. The catalytic current was linear with H 2 O 2 concentration from 2.5 to 212.5, 212.5 to 1662.5 and 1662.5 to 6662.5 μM and the sensitivity were 12.2, 5.3 and 2.4 μA mM −1 cm −2 , respectively. Furthermore, the proposed sensor showed a good anti-interference capacity, repeatability and stability.
研究领域:
分析化学
·
材料科学
·
电化学
·
生物传感器
·
纳米材料
·
环境监测
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）