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Characterization and developmental expression of AmphiMef2 gene in amphioxus

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Science China(Life Sciences) 2007年第5期50卷 637-641页

作者： zhang Ying WANG LiFeng SHAO Ming zhang hongwei Institute of Developmental Biology Life Science College Key Lab of Experimental Teratology of Ministry of Education Shandong University Jinan 250100 China Institute of Developmental Biology Life Science College Key Lab of Experimental Teratology of Ministry of Education Shandong University Jinan 250100 China Institute of Developmental Biology Life Science College Key Lab of Experimental Teratology of Ministry of Education Shandong University Jinan 250100 China Institute of Developmental Biology Life Science College Key Lab of Experimental Teratology of Ministry of Education Shandong University Jinan 250100 China

Myocyte enhancer factor 2 proteins are members of MADS family of transcription factors, which can control the expression of muscle-specific genes in vertebrates. However, not all Mef2 genes are es-sential for muscle development in invertebrates. Here we have isolated a full-length cDNA from am-phioxus, designated AmphiMef2. The predicted amino acid sequence has highly conserved MADS and MEF2 domains, showing higher identity with the corresponding regions of its homologues in verte-brates than those in invertebrates. Results from whole-mount in situ hybridization show that the ex-pression of AmphiMef2 initially appears in the presomitic mesoderm at early neurula stage, then the transcripts are detected in both the somites and the unsegmented presomitic mesoderm. At 36 h larval stage, the expression is only detected in the posterior somites. By 48 h larval stage, the expression is shifted to the preoral pit (a homologous organ to the vertebrate adenohypophysis) and persists until at least 72 h larval stage. The results suggest that AmphiMef2 may be not only involved in the myogenesis but also the development or function of the preoral pit in amphioxus.

关键词： AmphiMef2, amphioxus, developmental expression, myogenesis, preoral pit

Simplified mathematical model of proton exchange membrane fuel cell based on horizon fuel cell stack

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Journal of Modern Power Systems and Clean Energy 2016年第4期4卷 668-679页

作者： Ibrahim M.M.SALEH Rashid ALI hongwei zhang Materials and Engineering Research Institute Sheffield Hallam UniversitySheffieldUK

This paper presents a simplified zero-dimensional mathematical model for a self-humidifying proton exchange membrane(PEM)fuel cell stack of 1 k *** model incorporates major electric and thermodynamic variables and parameters involved in the operation of the PEM fuel cell under different operational *** of each of these parameters and variables upon the operation and the performance of the PEM fuel cell are *** mathematical equations are modeled by using Matlab-Simulink tools in order to simulate the operation of the developed model with a commercial available 1kW horizon PEM fuel cell stack(H-1000),which is used for the purposes of model validation and tuning of the developed *** model can be extrapolated to higher wattage fuel cells of similar *** equation is presented to determine the impact of using air to supply the PEM fuel cell instead of pure oxygen upon the concentration losses and the output voltage when useful current is drawn from it.

关键词： Proton exchange membrane(PEM)fuel cell Activation losses Ohmic losses Concentration losses Cathode-anode model Membrane hydration model

Age-hardening characteristic of an Al-Zn-Mg-Cu alloy produced by spray deposition

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Rare Metals 2007年第2期26卷 163-168页

作者： WANG Feng XIONG Baiqing zhang Yongan ZHU Baohong LIU hongwei zhang Zhihui WANG Zixing State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous Metals Beijing 100088 China

Al-10.8Zn-2.8Mg-1.9Cu alloy was synthesized by spray atomization and deposition technique. GP zones and age-hardening process in the alloy were investigated using high-resolution electron microscopy （HREM）, selected area diffraction （SAD）, and differential scanning calorimetry （DSC） analysis. The results indicated that spray deposition process accelerated the aging kinetics of the alloy at an aging temperature of 120℃, thereby reducing the peak aging time to 16 h. GPⅠ and GPⅡ are the two types of zones that are major precipitates for the alloy under peak-aged condition. The precipitation sequence for the alloy is also discussed.

关键词： aluminium alloy precipitation GP zone spray deposition

Selection of the best initial orbital elements of satellite based on fuzzy integration evaluation method

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Journal of Systems Engineering and Electronics 2006年第3期17卷 566-570页

作者： Yang Yong'an zhang hongwei Feng Zuren Luo Yongjin Xi'an Jiaotong Univ. Xi'an 710049 P. R. China Xi'an Satellite Control Center Xi'an 710043 P. R. China

The fuzzy integration evaluation method （FIEM） is studied in order to select the best orbital elements from the multi-group initial orbits determined by a satellite TT＆C （Tracking, Telemetry and Control） center with all kinds of data sources. By employing FIEM together with the experience of TT＆C experts, the index system to evaluate the selection of the best initial orbits is established after the data sources and orbit determination theories are studied. Besides, the concrete steps in employing the method are presented. Moreover, by taking the objects to be evaluated as evaluation experts, the problem of how to generate evaluation matrices is solved. Through practical application, the method to select the best initial orbital elements has been proved to be flexible and effective The originality of the method is to find a new evaluation criterion （comparing the actually tracked orbits） replacing the traditional one （comparing the nominal orbits） for selecting the best orbital elements.

关键词： system engineering fuzzy integration evaluation method satellite initial orbit TT&C system.

Migration and transformation of Sb are affected by Mn(Ⅲ/Ⅳ)associated with lepidocrocite originating from Fe(Ⅱ)oxidation

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Journal of Environmental Sciences 2022年第5期34卷 308-318页

作者： Yalu Shao Qian Sun Liangkai Wang Weiyong Zhan hongwei zhang Hua Zhong State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China School of Agriculture and Food The University of MelbourneVictoria 3010Australia College of Agricultural Sciences and Engineering Hohai UniversityNanjing 210098China

Antimony(Sb)is a recognized priority pollutant with toxicity that is influenced by its mi-gration and transformation *** of Fe(Ⅱ)to Fe(Ⅲ)oxides,which is a com-mon phenomenon in the environment,is often accompanied by the formation of Mn(Ⅲ/Ⅳ)and might affect the fate of *** this study,incorporated Mn(Ⅲ)and sorbed/precipitated Mn(Ⅲ/Ⅳ)associated with lepidocrocite were prepared by adding Mn(Ⅱ)during and after Fe(Ⅱ)oxidation,respectively,and the effects of these Mn species on Sb fate were *** results indicated that the association of these Mn species with lepidocrocite obviously enhanced Sb(Ⅲ)oxidation to Sb(V),while concomitantly inhibiting Sb sorption due to the lower sorption capacity of lepidocrocite for Sb(V)than Sb(Ⅲ).Additionally,Mn oxide equivalents increased in the presence of Sb,indicating that Sb oxidation by Mn(Ⅲ/Ⅳ)associated with lepidocrocite was a continuous recycling process in which Mn(Ⅱ)released from Mn(Ⅲ/Ⅳ)reduction by Sb(Ⅲ)could be oxidized to Mn(Ⅲ/Ⅳ)*** recycling pro-cess was favorable for effective Sb(Ⅲ)***,Sb(Ⅴ)generated from Sb(Ⅲ)ox-idation by Mn(Ⅲ/Ⅳ)enhanced Mn(Ⅱ)sorption at the beginning of the process,and thus favored Mn(Ⅲ/Ⅳ)formation,which could further promote Sb(Ⅲ)oxidation to Sb(V).Over-all,this study elucidated the effects of Mn(Ⅲ/Ⅳ)associated with lepidocrocite arisen from Fe(Ⅱ)oxidation on Sb migration and transformation and revealed the underlying reaction mechanisms,contributing to a better understanding of the geochemical dynamics of Sb.

关键词： Antimony Manganese Lepidocrocite Sorption Oxidation

Effects of a novel bimetallic catalytic biofilter-based pretreatment technique on the form of ultrafiltration membrane fouling

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Chinese Journal of Chemical Engineering 2020年第10期28卷 2513-2522页

作者： Songze Hao Xuehui Zhao hongwei zhang Yun Wu Cheng Fang Xujia Wang State Key Laboratory of Separation Membrane and Membrane Process Tiangong UniversityTianjin 300387China School of Materials Science and Engineering Tiangong UniversityTianjin 300387China School of Environmental Science and Engineering Tiangong UniversityTianjin 300387China

Pretreatments of influents using bimetallic catalytic biofilter(BC-biofilter)can help reduce transmembrane *** ultrafiltration membranes coupled with a conventional biofilter pretreatment,the cake layer resistance accounts for 25.0%of the total ***,for those coupled with BC-biofilter pretreatment,the cake layer resistance accounts only for 12.5%of the total *** laser scanning microscopy is employed to determine the porosity of cake *** is found that ultrafiltration membranes with BC-biofilter pretreatment show a cake layer porosity of up to 0.56 or greater,whereas those with a conventional biofilter pretreatment exhibit a cake layer porosity of only *** is because micro-flocculation occurs in the effluents of *** flocs generated through flocculation deposit on membrane surfaces to create highly porous cake ***,catalytic reduction can increase the zeta potentials of the biofilter *** makes the deposition of colloidal particles and flocs on membrane surfaces difficult under electrostatic ***,micro-flocculation after BC-biofilter pretreatment can remove colloidal particles with particle sizes of200–350 nm in *** can effectively prevent the blockage of ultrafiltration membrane ***,compared to conventional biofilter,BC-biofilter pretreatment can more effectively reduce the number of colloidal particles and the van der Waals forces of ultrafiltration *** can also change the action directions of electric double layers and thereby mitigate ultrafiltration membrane fouling.

关键词： Catalytic reduction Micro-flocculation Cake layer Membrane pore Membrane fouling

Biosynthetic CdS-Thiobacillus thioparus hybrid for solar-driven carbon dioxide fixation

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Nano Research 2023年第4期16卷 4531-4538页

作者： Guangyu Liu Feng Gao hongwei zhang Lei Wang Chao Gao Yujie Xiong Hefei National Laboratory for Physical Sciences at the Microscale and School of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China Institute of Energy Hefei Comprehensive National Science Center350 Shushanhu Rd.Hefei 230031China State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Synergistically combining biological whole-cell bacteria with man-made semiconductor materials innovates the way for sustainable solar-driven CO_(2)fixation,showing great promise to break through the bottleneck in traditional chemical photocatalyst ***,most of the biohybrids require uneconomical organic nutrients and anaerobic conditions for the successful cultivation of the bacteria to sustain the CO_(2)fixation,which severely limits their economic viability and applicability for practical ***,we present an inorganic-biological hybrid system composed of obligate autotrophic bacteria Thiobacillus thioparus(***)and CdS nanoparticles(NPs)biologically precipitated on the bacterial surface,which can achieve efficient CO_(2)fixation based entirely on cost-effective inorganic salts and without the restriction of anaerobic *** optimized interface between CdS NPs and *** formed by biological precipitation plays an essential role for *** efficiently receiving photogenerated electrons from CdS NPs and thus changing the autotrophic way from chemoautotroph to *** a result,the *** biohybrid realizes the solar-driven CO_(2)fixation to produce multi-carbon glutamate synthase and biomass under visible-light irradiation with CO_(2)as the only carbon *** work provides significant inspiration for the further exploration of the solar-driven self-replicating biocatalytic system to achieve CO_(2)fixation and conversion.

关键词： biohybrids solar-driven CO_(2)fixation carbon cycle autotrophic bacteria Thiobacillus thioparus cadmium sulfide

Corrosion mechanisms of Zr-based bulk metallic glass in NaF and NaCl solutions

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Journal of Materials Science & Technology 2020年第11期42卷 33-43页

作者： zhangweijia Qiu Zhengkun Li Huameng Fu hongwei zhang Zhengwang Zhu Aimin Wang Hong Li Long zhang Haifeng zhang School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shenyang National Laboratory for Material Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Shenyang Amorphous Metal Manufacturing Co. LtdShenyang 110000China Dongguan Eontec Co. LtdDongguan 523662China

So far,some investigations related to the corrosion mechanism of Zr-based metallic glasses in solutions containing Cl-have been ***,few attentions have been paid to the situation in F--containing *** paper describes the corrosion behaviours of Zr52Al10Ni6Cu32 bulk metallic glass(BMG)in Na F and Na Cl aqueous *** corrosion mechanism of Zr-based BMG in F–containing solution was proposed for the first *** was found that in Na Cl solutions,Zr-based BMG samples underwent typical pitting *** dissolution of Zr,Al and enrichment of Cu were observed in corrosion ***,corrosion occurred in the form of general breakdown of passive film in Na F *** difference is interpreted in terms of the binding ability of anions to surrounding molecules,i.e.,Cl-with loose surrounding water passes through the passive film to cause pitting;F-with a tight surrounding molecules layer absorbs on passive film then coordinates with cations from matrix.

关键词： Metallic glass Zirconium Corrosion behavior Pitting corrosion Passivation

Simultaneous enhancement of strength and ductility of body-centered cubic TiZrNb multi-principal element alloys via boron-doping

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Journal of Materials Science & Technology 2021年第19期78卷 74-80页

作者： Jingyu Pang hongwei zhang Long zhang Zhengwang Zhu Huameng Fu Hong Li Aimin Wang Zhengkun Li Haifeng zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Material Science and Engineering University of Science and Technology of ChinaShenyang 110016 China Ji Hua Laboratory in Foshan China

Body-centered cubic(BCC)multi-principal element alloys(MPEAs)have intrinsic high strength but poor ductility,which greatly limits their potential *** we present the boron-doping strategy to enhance the strength and ductility of TiZrNb MPEAs *** yield strength and ductility of the TiZrNb MPEA with boron addition of 500 ppm are increased by 19.0%and 48.7%compared to the boron-free TiZrNb MPEA,***-doping induced high efficiency in grain refinement from~96.0μm to~16.2μm is the main factor for *** dominated deformation mechanism involving cross slip and dislocation pining in the TiZrNb containing 500 ppm boron serves to enhance the strain-hardening capacity,resultant the enhancement of ductility from 7.8%to 11.6%.While the planar slip of dislocations is the dominated deformation mechanism for the boron-free TiZrNb.

关键词： Boron-doping TiZrNb Grain refinement Strain-hardening capacity Deformation mechanism