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Journal of Wuhan University of Technology(Materials Science) 2023年第1期38卷 192-198页

作者：李艳赵宇宏 YANG Xiaomin tian jinzhong College of Materials Science and Engineering North University of ChinaTaiyuan 030051China

The effects of pressure on structural,elastic and electronic properties of Mg_(x)La(x=1,2,3)compounds are investigated by using CASTEP program based on the density functional *** calculated equilibrium lattice parameters at zero pressure agree well with available experimental and theoretical *** calculated DOS show that the structure of these compounds remains mechanically stable and structural phase transformation is not induced with increasing pressure from 0 to 30 GPa,and their structural stability increases with *** ductility of MgLa can be improved by increasing pressure,which is the same as Mg_(2)La in 0-20 GPa,while brittle behavior turns into ductile behavior in 0-5 GPa for Mg_(3)*** resistance to volume deformation of Mg_(x)La(x=1,2,3)compounds can be improved as the pressure *** shear deformation resistance and elastic stiffness of Mg_(3)La can be enhanced by rising pressure,but MgLa and Mg_(2)La increase first and then decrease when pressure is up to 25 *** addition,the three compounds exhibit the elastic anisotropy with pressure.

关键词： Mg-La alloys elastic properties electronic structure first-principles

Formate as a supplementary substrate facilitates sugar metabolism and solvent production by Clostridium beijerinckii NCIMB 8052

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Synthetic and Systems Biotechnology 2023年第2期8卷 196-205页

作者： Ran Zhao Wenyue Dong Chen Yang Weihong Jiang jinzhong tian Yang Gu CAS-Key Laboratory of Synthetic Biology CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China University of Chinese Academy of Sciences Beijing100049China

Microbial utilization and conversion of organic one-carbon compounds,such as formate and methanol that can be easily produced from CO_(2),has emerged as an attractive approach for *** this study,we discovered Clostridium beijerinckii NCIMB 8052,a typical solventogenic Clostridium strain,to be a native formate-utilizing bacterium.^(13)C isotope analysis showed that formate could be metabolized via both assimilation and dissimi-lation pathways in *** NCIMB ***,the use of formate as the supplementary substrate by this strain could significantly enhance its glucose consumption and ABE(acetone-butanol-ethanol)production,largely due to the up-regulation of genes responsible for glycolysis and glucose transport under formate *** on these findings,we further improved formate tolerance of *** NCIMB 8052 by adaptive lab-oratory evolution,generating an evolved strain *** Cbei-FA01 strain could produce 23.0 g/L of ABE solvents using glucose and formate as dual substrates,~50%higher than that of the wild-type strain under the same ***,such a promotion effect of formate on ABE production by Cbei-FA01 was also observed in fermenting a glucose-xylose *** work reveals a previously unreported role of formate in biological ABE production,providing a new approach to utilize this one-carbon source.

关键词： Formate utilization Clostridium beijerinckii Metabolic pathways Adaptive laboratory evolution ABE solvents

Correlation between the mechanical properties and the<110>texture in a hot-rolled nearβtitanium alloy

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Journal of Materials Science & Technology 2022年第2期97卷 165-168页

作者： Ruifeng Dong Xiaoyang Zhang Chenhui Li Yuhong Zhao jinzhong tian Li Wu Hua Hou School of Materials Science and Engineering North University of ChinaTaiyuanShanxi 030051PR China State Key Laboratory of Solidification ProcessingNorthwestern Polytechnical UniversityXi’anShaanxi 710072PR China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’anShaanxi 710072PR China

*** Nearβtitanium alloys have been considered as a potential material to fabricate high-strength fasteners in aerospace field owing to their high specific strength,good crack and fatigue resistance[1,2].It is well known that the processing technology determines the microstructure,and the microstructure eventually correlates with the performance of alloys.

关键词： microstructure strength alloy

Selenomethionine alleviates chronic heat stress-induced breast muscle injury and poor meat quality in broilers via relieving mitochondrial dysfunction and endoplasmic reticulum stress

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Animal Nutrition 2024年第1期16卷 363-375页

作者： jinzhong Jing Jiayi Wang Xiaoyu Xiang Shenggang Yin Jiayong Tang Longqiong Wang Gang Jia Guangmang Liu Xiaoling Chen Gang tian Jingyi Cai Bo Kang Lianqiang Che Hua Zhao Key Laboratory for Animal Disease-Resistance Nutrition of Ministry of Education of China Ministry of Agriculture and Rural Affairsof Sichuan ProvinceAnimal Nutrition InstituteSichuan Agricultural University College of Animal Science and Technology Sichuan Agricultural University

In the present study,the chronic heat stress （CHS） broiler model was developed to investigate the potential protection mechanism of organic selenium （selenomethionine,SeMet） on CHS-induced skeletal muscle growth retardation and poor meat *** hundred Arbor Acres male broilers （680±70 g,21 d old） were grouped into 5 treatments with 8 replicates of 10 broilers per *** in the control group were raised in a thermoneutral environment （22±2°C） and fed with a basal *** other four treatments were exposed to hyperthermic conditions （33±2°C,24 h in each day） and fed on the basal diet supplied with SeMet at 0.0,0.2,0.4,and 0.6 mg Se/kg,respectively,for 21 *** showed that CHS reduced （P<0.05） the growth performance,decreased （P<0.05） the breast muscle weight and impaired the meat quality of breast muscle in *** induced protein metabolic disorder in breast muscle,which increased （P<0.05） the expression of caspase 3,caspase 8,caspase 9 and ubiquitin proteasome system related genes,while decreased the protein expression of *** also decreased the antioxidant capacity and induced mitochondrial stress and endoplasmic reticulum （ER） stress in breast muscle,which increased （P<0.05） the ROS levels,decreased the concentration of ATP,increased the protein expression of HSP60 and CLPX,and increased （P<0.05） the expression of ER stress *** SeMet supplementation linearly increased （P<0.05） breast muscle Se concentration and exhibited protective effects via up-regulating the expression of the selenotranscriptome and several key selenoproteins,which increased （P<0.05） body weight,improved meat quality,enhanced antioxidant capacity and mitigated mitochondrial stress and ER ***'s more,SeMet suppressed protein degradation and improved protein biosynthesis though inhibiting the caspase and ubiquitin proteasome system and promoting the mTOR-4EBP1 *** conclusion,dietary SeMet supplementation increases the expression of

关键词： Broiler Chronic heat stress Skeletal muscle Meat quality Mitochondrial dysfunction Endoplasmic reticulum stress

Multiplex genome editing using a dCas9-cytidine deaminase fusion in Streptomyces

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Science China(Life Sciences) 2020年第7期63卷 1053-1062页

作者： Yawei Zhao jinzhong tian Guosong Zheng Jun Chen Chuanwen Sun Zhongyi Yang Andrei A.Zimin Weihong Jiang Zixin Deng Zhijun Wang Yinhua Lu College of Life Sciences.Shanghai Normal University Shanghai 200234China State Key Laboratory of Microbial Metabolism School of Life Sciences and Biotechnology Shanghai Jiao Tong UniversityShanghai 200030China Key Laboratory of Synthetic Biology CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China School of Life Science Taizhou UniversityTaizhou 318000China Institute of Biochemistry and Physiology of Microorganisms Russian Academy of SciencesPushchino 142290Russia Shanghai Engineering Research Center of Plant Germplasm Resources College of Life SciencesShanghai Normal UniversityShanghai 200234China

CRISPR/Cas-mediated genome editing has greatly facilitated the study of gene function in Streptomyces. However, it could not be efficiently employed in streptomycetes with low homologous recombination(HR) ability. Here, a deaminase-assisted base editor d Cas9-CDA-ULstr was developed in Streptomyces, which comprises the nuclease-deficient Cas9(dCas9), the cytidine deaminase from Petromyzon marinus(PmCDA1), the uracil DNA glycosylase inhibitor(UGI) and the protein degradation tag(LVA tag). Using d Cas9-CDA-ULstr , we achieved single-, double-and triple-point mutations(cytosine-to-thymine substitutions)at target sites in Streptomyces coelicolor with efficiency up to 100%, 60% and 20%, respectively. This base editor was also demonstrated to be highly efficient for base editing in the industrial strain, Streptomyces rapamycinicus, which produces the immunosuppressive agent rapamycin. Compared with base editors derived from the cytidine deaminase rAPOBEC1, the PmCDA1-assisted base editor dCas9-CDA-ULstr could edit cytosines preceded by guanosines with high efficiency, which is a great advantage for editing Streptomyces genomes(with high GC content). Collectively, the base editor dCas9-CDA-ULstr could be employed for efficient multiplex genome editing in Streptomyces. Since the d Cas9-CDA-ULstr -based genome editing is independent of HR-mediated DNA repair, we believe this technology will greatly facilitate functional genome research and metabolic engineering in Streptomyces strains with weak HR ability.

关键词： base editors dCas9-CDA-ULstr multiplex editing Streptomyces

Mg和Sc掺杂AlLi相的弹性性质和德拜温度的第一性原理研究

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特种铸造及有色合金 2022年第8期42卷 940-943页

作者：田晋忠马圣洁陈瀚鲁若鹏赵宇宏侯华中北大学材料科学与工程学院

基于第一性原理研究了Mg和Sc对AlLi相的弹性模量、各向异性和德拜温度的影响。结果表明,AlLi、Al_(63)Li_(64)X和Al_(64)Li_(63)X(X=Mg和Sc)相在0 K均能形成稳定结构且满足力学稳定性判据。Mg和Sc能提高AlLi相的剪切模量和杨氏模量,但... 详细信息

基于第一性原理研究了Mg和Sc对AlLi相的弹性模量、各向异性和德拜温度的影响。结果表明,AlLi、Al_(63)Li_(64)X和Al_(64)Li_(63)X(X=Mg和Sc)相在0 K均能形成稳定结构且满足力学稳定性判据。Mg和Sc能提高AlLi相的剪切模量和杨氏模量,但对改善AlLi相的体积模量起消极作用。AlLi、Al_(63)Li_(64)X和Al_(64)Li_(63)X相的力学性能呈各向异性,其中Al_(64)Li_(63) Mg的各向异性程度最高。AlLi相的脆性随着Mg或Sc的掺杂而增大。AlLi、Al_(63)Li_(64)X和Al_(64)Li_(63)X相的硬度和德拜温度具有相同的变化趋势。

关键词：第一性原理 AlLi相弹性性质德拜温度

压力对Al_(7)Cu_(2)Fe相的力学及热力学性质的影响

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深圳大学学报（理工版） 2021年第4期38卷 427-432页

作者：唐大富田晋忠张永梅山西省锅炉压力容器监督检验研究院山西太原030012 中北大学材料科学与工程学院山西太原030051 中北大学理学院山西太原030051

基于密度泛函理论的VASP(Vienna ab-initio simulation package)软件包进行第一性原理计算,研究压力状态下Al_(7)Cu_(2)Fe相的能带和各向异性变化情况.结果表明,在0~50 GPa的压力范围内Al_(7)Cu_(2)Fe相具有金属性,且压力有助于提高能... 详细信息

基于密度泛函理论的VASP(Vienna ab-initio simulation package)软件包进行第一性原理计算,研究压力状态下Al_(7)Cu_(2)Fe相的能带和各向异性变化情况.结果表明,在0~50 GPa的压力范围内Al_(7)Cu_(2)Fe相具有金属性,且压力有助于提高能带中原子轨道的扩展性.Al_(7)Cu_(2)Fe相的(100)和(010)晶面的弹性各向异性随着压力升高而增强,而(110)晶面的弹性各向异性随着压力的升高呈波动上升趋势.基于准谐德拜模型,研究Al_(7)Cu_(2)Fe相的体积模量、德拜温度、热容和热膨胀系数随温度和压力的变化情况.结果表明,外加压力和温度对Al_(7)Cu_(2)Fe相热力学性质的影响是相反的.外加压力能有效提升Al_(7)Cu_(2)Fe相的体积模量和德拜温度,而温度升高会导致体积模量和德拜温度降低.Al_(7)Cu_(2)Fe相的热容和热膨胀系数在温度和压力下的变化规律基本一致.

关键词：金属材料第一性原理 Al_(7)Cu_(2)Fe 压力各向异性能带热力学性质 VASP

基于集合匹配尺度的邻域集合概率法及其在梅雨锋暴雨预报中的适用性

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热带气象学报 2024年第2期40卷 313-325页

作者：徐渊闵锦忠庄潇然陈云辉张璐田高山江西省气象台江西南昌330096 南京信息工程大学气象灾害教育部重点实验室/气象灾害预报预警与评估协同创新中心江苏南京210044 江苏省气象台江苏南京210008 民航西南空管局气象中心四川成都610202

概率预报是由集合预报衍生、包含不确定性信息的客观产品,对业务决策服务有重要的参考价值。传统的邻域集合概率法中,邻域半径固定不变,不符合实际天气过程中牵涉甚广的尺度谱。为此引入基于集合匹配尺度的邻域集合概率法(Neighborhood ... 详细信息

概率预报是由集合预报衍生、包含不确定性信息的客观产品,对业务决策服务有重要的参考价值。传统的邻域集合概率法中,邻域半径固定不变,不符合实际天气过程中牵涉甚广的尺度谱。为此引入基于集合匹配尺度的邻域集合概率法(Neighborhood Ensemble Probability based on Ensemble Agreement Scale,EAS_NEP),并在中国南方典型的梅雨锋暴雨中开展准确性和预报技巧的定量检验评估,以期验证该方法在此类过程中的适用性,并促进其在实际业务中的推广使用。联合扰动初始场、侧边界和物理过程所得到的集合预报能较好地表征实际的预报不确定性,进一步在此基础上比较了格点概率法、不同半径的邻域集合概率法以及EAS_NEP的优劣。试验结果表明,EAS_NEP能根据集合成员间的一致性程度,自适应地调整邻域半径,其在集中型降水中所确定的邻域半径通常大于分散型降水。动态调整的邻域半径既避免了半径过大时的过度平滑与关键信息丢失,又消除了半径较小所带来的奇异点,其空间分布呈阶梯型,空间连续性更优。此外,BS(布莱尔评分)、FSS(分数技巧评分)和ROC曲线(相对作用特征曲线)等定量评估结果也体现出EAS_NEP相比传统方法正的预报技巧,尤其是在分散型降水和高阈值检验时优势更明显。以上结果表明,EAS_NEP在梅雨锋暴雨的预报中具有较好的应用前景,运用在业务中能有效提升概率预报质量。

关键词：概率预报集合预报集合匹配尺度邻域集合概率梅雨锋暴雨

Al-Cu-Fe-Cr准晶增强铝基复合材料的研究

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材料导报 2018年第15期32卷 2635-2639页

作者：袁野王一帆侯华赵宇宏田晋忠中北大学材料科学与工程学院太原030051

采用常规铸造法制备了四元系Al-Cu-Fe-Cr准晶,利用XRD、SEM和TEM等分析手段,分析了准晶和其类似相的微观组织以及在热处理后的相转变。以ZL101合金为基体,Al-Cu-Fe-Cr准晶颗粒为增强体,通过机械搅拌的方法制备了Al-Cu-FeCr准晶/ZL101复... 详细信息

采用常规铸造法制备了四元系Al-Cu-Fe-Cr准晶,利用XRD、SEM和TEM等分析手段,分析了准晶和其类似相的微观组织以及在热处理后的相转变。以ZL101合金为基体,Al-Cu-Fe-Cr准晶颗粒为增强体,通过机械搅拌的方法制备了Al-Cu-FeCr准晶/ZL101复合材料,分析复合材料的微观组织和成分,并研究其力学性能。结果表明:铸态准晶合金组织中含有Al65Cu20-Fe10Cr5相(I+d)、准晶I相、λ-Al3Fe相以及少量的η-AlCu和θ-Al2Cu相,经880℃×30min热处理水淬后,λ相消失,得到了高纯度的Al65Cu20Fe10Cr5相和准晶I相;复合材料中由于准晶和基体之间的相互扩散,使得准晶相失稳发生分解;随着准晶含量的增加,复合材料的抗拉强度增加,延伸率减小,但由于Cr元素的加入使针状的β-Fe相转变成汉字状或骨骼状的α-Fe相,对复合材料的延伸率有提升作用。

关键词： Al-Cu-Fe-Cr准晶热处理机械搅拌法铝基复合材料

间接挤压铸造水雷壳体用ZAlSi7Mg铝合金隔板件

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特种铸造及有色合金 2022年第4期42卷 446-450页

作者：孙晓平赵宇宏陈利文李志强景舰辉李沐奚田晋忠侯华中北大学材料科学与工程学院太原030051

采用SHP34-500A多功能液态成型机试生产了水雷壳体用ZAlSi7Mg铝合金隔板件,研究了不同比压、浇注温度和保压时间下铸件组织和力学性能的变化。结果表明,随着比压和保压时间的增加以及浇注温度下降,铸件的晶粒尺寸呈现减小的趋势。最佳... 详细信息

采用SHP34-500A多功能液态成型机试生产了水雷壳体用ZAlSi7Mg铝合金隔板件,研究了不同比压、浇注温度和保压时间下铸件组织和力学性能的变化。结果表明,随着比压和保压时间的增加以及浇注温度下降,铸件的晶粒尺寸呈现减小的趋势。最佳工艺参数是比压为130 MPa、浇注温度为720℃、保压时间为20 s。从挤压的铸件本体取样,其抗拉强度达209.9 MPa,屈服强度达121.8 MPa,伸长率达10.3%;经过热处理后铸件抗拉强度达259 MPa,屈服强度达179.6 MPa,伸长率达11.8%。

关键词：挤压铸造工艺参数 ZAlSi7Mg合金力学性能