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Exploration of the key functional proteins from an efficient cellulolytic microbial consortium using dilution-to-extinction approach

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Journal of Environmental Sciences 2016年第5期28卷 199-207页

作者： qinghua zhang Hanguang Li Xiangdong Zhu Fenju Lai Zhijun Zhai Yuanxiu Wang College of Bioscience and engineering Jiangxi engineering Laboratory for the development and Utilization of Agricultural Microbial ResourcesJiangxi Agricultural University Nanehan9 330045 China

In the present study, the cellulose binding proteins（CBPs） secreted by a putative cellulolytic microbial consortium were isolated and purified by affinity digestion. The purified CBPs were subsequently separated by sodium dodecyl sulfate–polyacrylamide gel electrophoresis（SDS-PAGE）. Using mass spectrometric analyses, eight CBPs were identified and annotated to be similar to known proteins secreted by Clostridium clariflavum DSM 19732 and Paenibacillus sp. W-61. In addition, in combination with dilution-to-extinction approach and zymogram analysis technique, CBPs 6（97 k Da） and 12（52 k Da） were confirmed to be the key functional proteins that influence cellulolytic activities. Moreover, structural domain analyses and enzymatic activity detection indicated that CBPs 6 and 12 contained glycoside hydrolase families（GH） 9 and 48 catalytic modules, which both revealed endoglucandase and xylanase activities. It was suggested that the coexistence of GH9 and GH48 catalytic domains present in these two proteins could synergistically promote the efficient degradation of cellulose.

关键词： Microbial consortium Cellulolytic Cellulose binding protein Dilution-to-extinction approach

Polychlorinated dibenzo-p-dioxins and dibenzofurans in different tissues of the cormorants (Phalacrocorax carbo) from Dongting Lake,China

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Journal of Environmental Sciences 2011年第10期23卷 1709-1713页

作者： Lirong Gaol Minghui Zheng Bing zhang Wenbin Liu Ke Xiao Guijin Su qinghua zhang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Tissue distribution provides important information regarding the pharmacokinetic behavior of pollutants and is invaluable when analyzing the risk posed to avian species by the exposure to such kind of pollutants. In this study, concentrations of polychlorinated dibenzo-p-dioxins （PCDDs） and polychlorinated dibenzofurans （PCDFs） were determined in muscle, liver, spleen, kidney, stomach, gall bladder, skin, heart, pancreas, intestine and lung tissue extracts of cormorants collected from Dongting Lake, China. Tissue distribution results showed preferential accumulation of PCDD/Fs in both liver and skin. The total concentration of PCDD/Fs ranged from 421 to 5696 pg/g lipid weight. Octachlorinated dibenzo-p-dioxin （OCDD） was the predominant congener in all tissues and contributed between 31% and 82% to all 17 PCDD/Fs in different tissues. The liver/muscle ratios progressively increased with the degree of chlorination of PCDDs, except for OCDD. The relative toxic potential of PCDDs and PCDFs in tissues were calculated using the World Health Organization （WHO） Toxic Equivalency Factors （TEFs） for birds. The concentrations of WHO-toxic equivalent in different tissues ranged between 14.8 and 2021 pg/g lipid weight. These results indicated PCDD/Fs may have been bio-accumulated in cormorant via food-web. Furthermore, when compared with studies reported in the literatures, the PCDD/Fs levels in the cormorant collected from Dongting Lake were still relatively high.

关键词： polychlorinated dibenzo-p-dioxins dibenzofurans cormorant Dongting Lake distribution tissue

CFD simulation of flow and mixing characteristics in a stirred tank agitated by improved disc turbines

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Chinese Journal of Chemical Engineering 2022年第10期50卷 95-107页

作者： Zhuotai Jia Lele Xu Xiaoxia Duan Zai-Sha Mao qinghua zhang Chao Yang CAS Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China School of Chemical Engineering Nanjing Tech UniversityNanjing 211816China

To reduce the power consumption and improve the mixing performance in stirred tanks,two improved disc turbines namely swept-back parabolic disc turbine(SPDT)and staggered fan-shaped parabolic disc turbine(SFPDT)are *** validation of computational fluid dynamics(CFD)model with experimental results,CFD simulations are carried out to study the flow pattern,mean velocity,power consumption,pumping capacity and mixing efficiency of the improved and traditional impellers in a dished-bottom tank under turbulent flow conditions,The results indicate that compared with the commonly used parabolic disc turbine(PDT),the power number of proposed SPDT and SFPDT impellers is reduced by 43%and 12%,and the pumping efficiency is increased by 68%and 13%,***,under the same power consumption(0-700 W·m^(-3)),the mixing performance of both SPDT and SFPDT is also superior to that of Rushton turbine and PDT.

关键词： Flow regime Mixing time Stirred vessel Computational fluiddynamics Improved discturbine

Nickel-iron in the second coordination shell boost single-atomicsite iridium catalysts for high-performance urea electrooxidation

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Nano Research 2024年第5期17卷 3919-3926页

作者： Xiaoyu Chen Jiawei Wan Jing Chai Liang zhang Fang zhang qinghua zhang Lin Gu Lirong Zheng Ranbo Yu Department of Physical Chemistry School of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijing 100083China State Key Laboratory of Biochemical Engineering Key Laboratory of Biopharmaceutical Preparation and DeliveryChinese Academy of SciencesInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Center for Combustion Energy School of Vehicle and MobilityState Key Laboratory of Intelligent Green Vehicle and MobilityTsinghua UniversityBeijing 100084China Analysis and Testing Center Beijing Institute of TechnologyBeijing 100081China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Beijing National Center for Electron Microscopy and Laboratory of Advanced Materials Department of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

Single-atom catalysts(SACs)with high catalytic activity as well as great stability are demonstrating great promotion in electrocatalytic energy conversion,which is also a big challenge to ***,we proposed a facile synthetic strategy to construct nickel-iron bimetallic hydroxide nanoribbon stabilized single-atom iridium catalysts(Ir-NiFe-OH),where the nickel-iron hydroxide nanoribbon not only can serve as good electronic conductor,but also can well stabilize and fully expose single-atom *** as catalyst for urea oxidation reaction(UOR),it exhibited excellent UOR performance that it only needed a low operated potential of 1.38 V to achieve the current density of 100 mA·cm^(-2).In-situ Fourier transform infrared spectroscopy,X-ray absorption spectrum,and density functional theory calculations proved that Ir species are active centers and the existence of both Ni and Fe in the local structure of Ir atom can optimize the d-band center of Ir species,promoting the adsorption of intermediates and desorption of products for *** hydrogen evolution reaction(HER)/UOR electrocatalytic cell demanded voltages of 1.46 and 1.50 V to achieve 50 and 100 mA·cm^(-2),respectively,which demonstrated a higher activity and better stability than those of conventional *** work opens a new avenue to develop catalysts for UORs with boosted activity and stability.

关键词： single-atom iridium coordinate structure nanoribbon urea electrooxidation

Relationship between expression of hepatocyte grow factor and apoptosis of trophoblasts in hypertensive disorder complicating pregnancy

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Frontiers of Medicine 2007年第4期1卷 386-389页

作者： OUYANG Shan QIAO Fuyuan zhang qinghua Department of Gynecology and Obstetrics Central Hospital of WuhanWuhan 430014China Department of Gynecology and Obstetrics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

The aim of this study was to investigate the expression of hepatocyte growth factor(HGF)and Fas in placentas of uncomplicated pregnant women and those with hypertensive disorder complicating pregnancy(HDCP),and elucidate the possible relationship between HGF and apopto-sis of *** transcription-polymerase chain reaction(RT-PCR)was undertaken to examine the concentra-tion of HGF mRNA and Fas mRNA obtained from 34 cases of HDCP and 30 cases of uncomplicated *** expression of HGF mRNA in mild preeclampsia,severe preeclampsia and eclampsia cases was significantly lower than that in the uncomplicated cases(0.43P0.12,0.38P0.09,0.19P0.17 versus 0.67P0.19,P<0.05),while the expres-sion of Fas mRNAin mild preeclampsia,severe preeclampsia and eclampisa cases was significantly higher than that in the uncomplicated cases(1.58P0.26,2.96P0.14,5.98P1.17 versus 1.01P0.36,P<0.05).For HGF mRNA and Fas mRNA,there was no difference between gestational hyper-tension cases and control *** HGF mRNA or increased Fas mRNA was found along with the progress of *** correlation was found between the expressions of HGF and *** results indicate that HGF inhibits the apoptosis mediated by Fas,and the reduced expression of HGF in HDCP may be responsible for the apoptosis of trophoblasts.

关键词： hepatocyte growth factor pregnancy complica-tions cardiovascular hypertension trophoblasts apoptosis

Tough polyimide composites synergistically reinforced by carbon nanofiber-grafted carbon fiber and rGO for improved heat dissipation and electromagnetic interference shielding

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Journal of Materials Science & Technology 2023年第18期149卷 225-236页

作者： Zhiqiang Wu Jie Dong Xiuting Li Xin Zhao Wenjun Tan Chengchang Ji qinghua zhang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province College of Chemical and Materials EngineeringXuchang UniversityXuchang 461000China

The rapid miniaturization and a consequent increase in electromagnetic wave(EM)and heat emission in integrated electronic devices are now urgently desiring for multifunctional polymer composites that simultaneously possess high mechanical properties,excellent electromagnetic interference(EMI)shield-ing ability and heat dissipation ***,a series of novel polyimide-based composite films were constructed by rationally assembling the carbon nanofiber-grafted carbon fiber(NCF)and reduced graphene oxide(rGO)into a highly electrically and thermally conductive pathway within polyimide ma-trix via a sequential bidirectional freezing casting and hot-pressing *** combination of high tensile strength and toughness was obtained by incorporating rGO into the NCF-reinforced PI composite,giving rise to a hierarchical reinforcing structure of NCF and crack deflection induced by rGO *** high electrical conductivity(7.0×10^(3) S m^(-1))endows the PI/NCF30/rGO3.5 composite film with a good EMI shielding effectiveness of 45 ***,the well-aligned thermally conductive NCF and rGO and strong interfacial bonding between the polymer matrix and reinforcing fibers give rise to improved thermal conductivity(λ),particularly along the in-plane ***,the PI/NCF30/rGO3.5 exhibits an in-plane thermal conductivity of 5.18 W m^(-1) K^(-1),∼4.7 times increment compared to the pure PI(0.91 W m^(-1) K^(-1)).Besides,the resultant PI/NCF30/rGO3.5 composite film presents a superior Joule heat-ing performance with some features of fast thermal response,ease of regulation and sufficient ***,the developed multifunctional polyimide-based composite films demonstrate high potential as advanced EMI shielding materials with excellent heat dissipation.

关键词： Polyimide nanocomposites Mechanical performance Emi shielding Heat dissipation

Intra-Oceanic Subduction Termination and Reinitiation of the Eastern Neo-Tethys in Myanmar

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Journal of Earth Science 2024年第3期35卷 1053-1058页

作者： Yi Chen qinghua zhang Lin Chen Kaihui Shi Kyaing Sein State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Myanmar Geosciences Society Hlaing University CampusYangon 11062Myanmar

Subduction initiation and termination represent the birth and death of a subduction zone and are inevitable elements of terrestrial plate *** evidence demonstrates that subduction zone processes did not operate continuously and might involve multiple initiation and termination stages(Stern,2004),characterized by sustained subduction-zone death and *** geological and numerical studies focus on subduction initiation processes/mechanisms(see reviews in Yang,2022);however,subduction termination is often studied numerically at continental margins(Gerya,2022).How subduction termination proceeds in intra-oceanic settings remains enigmatic due to lacking geological records.

关键词： Eastern terrestrial continental

Interfacial engineering regulated by CeOx to boost efficiently alkaline overall water splitting and acidic hydrogen evolution reaction

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Journal of Materials Science & Technology 2022年第25期120卷 129-138页

作者： Jian Chen Zhen Hu Yang Ou qinghua zhang Xiaopeng Qi Lin Gu Tongxiang Liang College of Rare Earth Jiangxi University of Science and TechnologyGanzhou 341000China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China Institute of Physics Chinese Academy of ScienceBeijing 100190China

Development of a low-cost and durable bifunctional electrocatalyst with high catalytic activity by hybridizing rare earth metal and non-noble metal is of utmost ***,a bifunctional electrocatalyst consisting of MoO_(2)and CeO_(x)heterostructure is synthesized via interfacial ***,due to its unique hetero-interface with abundant oxygen vacancies,the MoO_(2)-CeO_(x)_(x)/NF is able to exhibit outstanding hydrogen evolution reaction(HER) performance with an overpotential of 26 mV at 10 mA cm^(-2),and a preferable oxygen evolution reaction(OER) overpotential of 272 mV at 100 mA cmin 1 M *** recorded HER and OER overpotentials of MoO_(2)-CeO_(x)/NF are clearly smaller than those of Pt/C(HER overpotential of 27 mV) and RuO(OER overpotential of 393 mV) at the same current *** importantly,MoO_(2)-CeO_(x)/NF can also exhibit good HER activity with an overpotential of 50 mV at 10 mA cmin acidic ***,it is expected that this work can offer a new approach in the realization of high-catalytic alkaline overall water splitting and acidic HER performance through the rational design of rare-earth metal and non-noble metal heterostructure.

关键词： Heterostructure Oxygen vacancies Cerium oxide Overall water splitting

Novel physical profperties in 5d electronic materials

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Fundamental Research 2023年第3期3卷 311-312页

作者： qinghua zhang Lin Gu Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Beijing National Center for Electron Microscopy and Laboratory of Advanced Materials Department of Materials Science and EngineeringTsinghua UniversityBejing 100084China

Along with the gradually expanding scope of material research,more and more 5d electronic-related materials are entering our ***,the variation of the radial distribution function and strong spin-orbit coupling(SOC)effect of 5d lectrons enables the discovery of novel physical *** with 3d and 4d electrons,5d electrons have their orbits further expanded in real space,thus forming competition between the strong spin-orbit coupling and electronic correlation,which results in a great number of novel quantum properties.

关键词： properties. electronic coupling