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Effect of void nucleation on microstructure and stress state in aluminum alloy tailor-welded blank

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Progress in Natural Science:Materials International 2021年第1期31卷 77-85页

作者： L.Xing M.zhan P.F.Gao M.li Y.D.Dong T.Y.Wang State Key Laboratory of Solidification Processing School of Materials Science and Engineering Northwestern Polytechnical University Shaanxi Key Laboratory of High-Performance Precision Forming Technology and Equipment Key Laboratory of High Performance Manufacturing for Aero Engine (Northwestern Polytechnical University) Ministry of Industry and Information Technology

The microscopic damage initiation characteristic in welded joint greatly determines the subsequent damage evolution and fracture behavior of aluminum alloy tailor-welded blank(TWB) during plastic forming. In this study, the interactive dependence of void nucleation on microstructure and stress state in the welded joint of a2219 aluminum alloy TWB was quantitatively explored by in-situ SEM testing. Moreover, a micromechanical model based on actual microstructure was adopted to reveal the underlying mechanisms from the perspective of microscopic heterogeneous deformation. The results showed that three void nucleation mechanisms, including particle-cracking, interface-debonding and matrix-cracking, coexisted in the deformation at different microstructure regions and stress states. The nucleation strain of each mechanism mainly depended on the particle volume fraction, grain size and stress triaxiality. Besides, the proportions of particle-cracking and interfacedebonding greatly varied with the grain size and particle volume fraction, and the variation law changed with the stress state. The proportion of matrix-cracking had a weak dependence on the microstructure, while increased with the stress triaxiality decreasing. It made the damage initiation in aluminum alloy welded joint transit from particle-cracking dominance to matrix-cracking dominance with the stress triaxiality *** micromechanical modeling results suggested that the changes of evolutions and distributions of Mises stress in particle, hydrostatic stress at interface and plastic strain in matrix with microstructure and stress state were responsible for the above effects.

关键词： Aluminum alloy Welded joint Void nucleation Microstructure Stress state Micromechanical model

稀释接种法和二次发酵法制备的绿色木霉生物有机肥肥料效应比较研究

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PEG-SO_3H as catalyst for the Beckmann rearrangement and dehydration of oximes

中国土壤与肥料 2024年第5期 162-168页

作者：邓杰王宇蕴唐伟魏雨泉李季徐智云南农业大学资源与环境学院云南昆明 650201 中国农业大学有机循环研究院(苏州) 江苏苏州 215100 云南农业大学资源与环境学院云南昆明 650201 中国农业大学有机循环研究院(苏州) 江苏苏州 215100 中国农业大学资源与环境学院北京 100193

生物有机肥中的功能性微生物是生物有机肥肥效的核心,生物有机肥的制造工艺决定了功能性微生物的数量和应用效果,绿色木霉兼具的促生和生防功能现已被广泛应用于生物有机肥的制备中.分别采用稀释接种法和二次发酵法在不同腐熟度(种子发... 详细信息

生物有机肥中的功能性微生物是生物有机肥肥效的核心,生物有机肥的制造工艺决定了功能性微生物的数量和应用效果,绿色木霉兼具的促生和生防功能现已被广泛应用于生物有机肥的制备中.分别采用稀释接种法和二次发酵法在不同腐熟度(种子发芽指数GI值为 50%、80%、100%)的堆肥物料接种绿色木霉制备生物有机肥,采用盆栽试验,研究两种工艺类型的生物有机肥在辣椒根系定殖能力及其对辣椒疫病的防控作用.结果发现,施用生物有机肥 24 d后,经过二次发酵法生产的生物有机肥(分别在堆肥物料GI值为 50%、80%和 100%时接种绿色木霉进行二次发酵生产的生物有机肥)的绿色木霉在辣椒植株根系定殖量分别为 1.5×105、2.3×105 和1.02×105 CFU/g,按照稀释接种法生产的生物有机肥(分别在堆肥物料GI值为 50%、80%和 100%时,按照稀释倍数接种绿色木霉生产的生物有机肥)的绿色木霉定殖量分别为 0.29×105、0.72×105 和 0.24×105 CFU/g;在GI值为 80%的堆肥物料条件接种绿色木霉,经过二次发酵生产的生物有机肥,绿色木霉在辣椒根际定殖能力最强;经过二次发酵的生物有机肥处理的辣椒疫病防治效果显著高于按照稀释倍数接种绿色木霉制成的生物有机肥处理,且以GI值为 80%的堆肥物料条件生产的生物有机肥的辣椒疫病防治效果最好.研究结果发现,以GI值为 80%的堆肥物料接种绿色木霉后,采用二次发酵方式生产的生物有机肥,7 d后的绿色木霉菌增殖量为 3.91 倍,表现出功能性微生物最好的增殖和定殖效果.综上所述,在制备绿色木霉生物有机肥时的最佳方法是在腐熟度为 80%的堆肥物料中接种绿色木霉进行二次发酵,可以提高绿色木霉的定殖效果,也可以提升绿色木霉生物有机肥的抗病效果.

关键词：不同腐熟度堆肥物料接种工艺绿色木霉定殖能力防治效果

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Chinese Chemical Letters 2009年第6期20卷 651-655页

作者： Xi Cun Wang Lei li Zheng Jun quan Hai Peng Gong He lin Ye Xiao Feng Cao Gansu Key Laboratory of Polymer Materials College of Chemistry and Chemical Engineering Northwest Normal University Lanzhou 730070 PR China

Under mild conditions, conversion of a variety of ketoximes and aldoximes to their corresponding amides and nitriles proceeded in the presence of PEG-SO3H with high yields.

关键词： Beckmann rearrangement PEG-SO3H Dehydration of oximes

Design and development of an ACCT for the Shanghai advanced proton therapy facility

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Nuclear Science and Techniques 2022年第10期33卷 41-52页

作者： Hong zhang Jun-Zhou li Rui Hou Sun An Shi-quan Xu You-Chun liu Peng-Jiao zhang Jie Song Yue-lin zhang College of Engineering and Applied Sciences Nanjing UniversityNanjing 210093China

The Shanghai advanced proton therapy facility is a proton cancer treatment device designed and built by the Shanghai Institute of applied physics at the Chinese academy of *** accelerator part comprises a proton linear accelerator(linac)injector and a circular *** alternating current current transformer(ACCT)is used for non-intercepting beam current measurement at the drift tube linac *** to the beam characteristics,the ACCT is required to complete real-time beam current and pulse width measurements at currents of3-30 mA,frequencies of 1-10 Hz,and pulse widths of40-400μ*** this paper,we report the design and development of an *** designed ACCT was simulated using CST Microwave Studio,and calibrated using an oscilloscope and signal *** in the output signal of the ACCT were investigated as a function of ceramic gap size,number of coil turns,and *** to the simulation and experimental results,the optimal number of coil turns was found to be *** addition,a low-pass filter was adopted to filter the noise introduced during long-distance signal transmission using a coaxial cable with the length of 20 *** calibration results show that the corresponding rise time of the ACCT is 800 ns with the sensitivity of 8.2 V/A and a droop of less than 1%,meeting the design requirements.

关键词： Beam current monitors ACCT Particle beam diagnostics

冠心病患者PCI术后认知功能改变的相关研究

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中国循证心血管医学杂志 2024年第5期16卷 625-630页

作者：潘昱庞丽张晓玲李全叶益聪玉献鹏赵昔良王晓怡曾勇首都医科大学附属北京安贞医院冠心病中心三病房北京100029 山东大学附属威海市立医院急诊科威海264200 北京智精灵科技有限公司北京100000

目的观察经皮冠状动脉介入治疗(PCI)和冠状动脉造影(CAG)对冠状动脉粥样硬化性心脏病(冠心病)患者围术期认知功能的影响,并探讨相应临床化验指标与认知功能障碍的相关性。方法连续收集于北京安贞医院心内科住院治疗的冠心病患者203例为... 详细信息

目的观察经皮冠状动脉介入治疗(PCI)和冠状动脉造影(CAG)对冠状动脉粥样硬化性心脏病(冠心病)患者围术期认知功能的影响,并探讨相应临床化验指标与认知功能障碍的相关性。方法连续收集于北京安贞医院心内科住院治疗的冠心病患者203例为研究对象,其中接受冠状动脉(冠脉)造影55例(CAG组),接受冠脉支架植入治疗148例(PCI组)。于术前及术后6 h,通过“基本认知能力测验”(BCAT)软件系统分别对两组患者术前及术后的加工速度、工作记忆及情景记忆进行检测,同时提取患者术前的相关实验室检查及手术相应临床指标。采用Wilcoxon符号秩检验比较患者的术前及术后认知功能评分的差异,采用皮尔逊相关系数评估各项实验室检查指标及临床指标与术后加工速度、工作记忆及情景记忆得分的相关性,采用多元线性回归评估各检查指标对于术后加工速度、工作记忆及情景记忆得分的影响。结果CAG组患者术前、术后各项认知功能评分均无显著性差异,而PCI组患者在加工速度、情景记忆两个维度上,术后的认知功能评分高于术前评分(P0.05)。相关分析表明PCI组患者的年龄与术后工作记忆得分有显著负相关关系(r=-0.258,P<0.01),手术用时与术后情景记忆得分有显著负相关关系(r=-0.206,P<0.05),血清超敏C反应蛋白(hs-CRP)与术后加工速度得分有显著负相关关系(r=-0.273,P<0.01),血清同型半胱氨酸(Hcy)与术前和术后加工速度得分有显著负相关关系(r=-0.288,P<0.01),血清游离三碘甲状腺原氨酸(FT3)与术后情景记忆得分有显著正相关关系(r=0.296,P<0.01)。多元线性回归结果显示,年龄是PCI组患者术后工作记忆得分的独立危险因素(β=-0.238,P<0.05),hs-CRP和Hcy是PCI组患者术后加工速度得分的独立危险因素(β=-0.218~-0.207,P<0.05),FT3是PCI组患者术后情景记忆得分的独立保护因素(β=0.224,P<0.05)。结论冠心病患者接受PCI治疗可加重患者围术期认知功能障碍,应在术前注意筛查患者的认知功能状况并及时进行干预。年龄、手术时间、血清hs-CRP和Hcy水平的增高以及FT3水平的降低是PCI手术患者术后认知功能减低的重要影响因素,血清hs-CRP、Hcy及FT3水平对冠脉介入治疗术后认知功能障碍可能具有早期预测作用。

关键词：冠状动脉介入治疗认知功能障碍超敏C反应蛋白同型半胱氨酸

Efficient inversions and duplications of mammalian regulatory DNA elements and gene clusters by CRISPR/Cas9

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分子细胞生物学报:英文版 2015年第4期7卷 284-298页

作者： Jinhuan li Jia Shou YaGuo Yuanxiao Tang YonghuWu Zhilian Jia Yanan Zhai Zhifeng Chen quan Xu Qiang Wu Key Laboratory of Systems Biomedicine(Ministry of Education) Center for Comparative BiomedicineInstitute of Systems BiomedicineShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Oncogenes and Related Genes Shanghai Cancer InstituteRenji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200240China Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders Ministry of EducationBio-X CenterSchool of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of Systems Biomedicine Shanghai Jiao Tong University School of MedicineShanghai 200240China

The human genome contains millions of DNA regulatory elements and a large number of gene clusters,most of which have not been tested *** clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated nuclease 9(Cas9)programed with a synthetic single-guide RNA(sgRNA)emerges as a method for genome editing in virtually any *** we report that targeted DNA fragment inversions and duplications could easily be achieved in human and mouse genomes by CRISPR with two ***,we found that,in cultured human cells and mice,efficient precise inversions of DNA fragments ranging in size froma few tens of bp to hundreds of kb could be *** addition,DNA fragment duplications and deletions could also be generated by CRISPR through trans-allelic recombination between the Cas9-induced double-strand breaks(DSBs)on two homologous chromosomes(chromatids).Moreover,junctions of combinatorial inversions and duplications of the protocadherin(Pcdh)gene clusters induced by Cas9 with four sgRNAs could be *** mice,we obtained founders with alleles of precise inversions,duplications,and deletions of DNA fragments of variable sizes by ***,we found that very efficient inversions were mediated by microhomology-mediated end joining(MMEJ)through short inverted *** showed for the first time that DNA fragment inversions could be transmitted through germlines in ***,we applied this CRISPR method to a regulatory element of the Pcdha cluster and found a new role in the regulation of members of the Pcdhg *** simple and efficient method should be useful in manipulating mammalian genomes to study millions of regulatory DNA elements as well as vast numbers of gene clusters.

关键词： DNA regulatory element inversion duplication deletion CRISPR/Cas9 enhancer genome manipulation gene cluster

linear Analysis of a Helix Traveling Wave Tube Filled with Plasma

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Linear Analysis of a Helix Traveling Wave Tube Filled with P...

Effect of the C.–1388 A>G polymorphism in chicken heat shock transcription factor 3 gene on heat tolerance

2002 3rd International Conference on Microwave and Millimeter Wave Technology

作者： Xie Hong-quan li Cheng-yue Yan Yang liu Sheng-gang Institute of High Energy Electronics University of Electronic Science and Technology of China

ISBN: (纸本)078037486X

＜正＞A helix type slow wave structure filled partially with plasma is immersed in a strong longitudinal magnetic *** means of sheath model and linear field theory,the dispersion relation of the slow wave structure is derived. Hybrid modes which are formed at frequencies where the phase velocities of electromagnetic wave and electrostatic wave coincide are *** trend of change for dispersion characteristic,interaction impedance and linear gain is analyzed in different plasma densities by numerical *** useful results are obtained on the basis of the discussion.

关键词： Helix traveling wave tube Plasma Hybrid modes

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Journal of Integrative Agriculture 2015年第9期14卷 1808-1815页

作者： zhanG Wen-wu KONG li-na zhanG De-xiang JI Cong-liang zhanG Xi-quan LUO Qing-bin College of Animal Science South China Agricultural University Key Laboary of Chicken Genetics Breeding and ReproductionMinistry of Agriculture/South China Agricultural University Guangdong Enterprise Laboary of Healthy Animal Husbandry and Environment Control South China Agricultural University Guangdong Wens Food Group limited Company

Heat stress is one of the main factors that inlfuence poultry production. Heat shock proteins (HSPs) are known to affect heat tolerance. The formation of HSPs is regulated by heat shock transcription factor 3 (HSF3) in chicken. A DNA pool was established for identifying single nucleotide polymorphisms (SNPs) of the chicken HSF3, and 13 SNPs were detected. The bioinformatic analysis showed that 8 SNPs had the capacity to alter the transcription activity of HSF3. The dual luciferase report gene assay showed that there was a signiifcant difference (PG (S1) and C.–1 388 A>G (S4) sites at the 5′-untranslated region (UTR) of chicken HSF3. The elec-trophoretic mobility shift assay showed that the S4 site was a transcription binding factor. The analysis of the association of the S1 and S4 sites with heat tolerance index revealed that the S4 site was signiifcantly correlated with the CD3+T cel , corticosterone, and T3 levels in lingshan chickens and with the heterophil/lymphocyte value in White Recessive Rock. These results showed that the S4 site at the 5′ UTR of chicken HSF3 might have an impact on heat tolerance in summer and could be used as a potential marker for the selection of chicken with heat tolerance in the future.

关键词： chicken heat shock factor 3 dual luciferase report gene heat tolerance

Global Positioning Scheme via quantum Teleportation

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Chinese Physics Letters 2023年第11期40卷 18-24页

作者：李有泉吕丽花朱启航 Chern Institute of Mathematics Nankai UniversityTianjin 300071China School of Physics Zhejiang UniversityHangzhou 310058China Collaborative Innovation Center of Advanced Microstructure Nanjing UniversityNanjing 210093China

quantum teleportation scheme is undoubtedly an inspiring theoretical discovery as an amazing application of quantum physics,which was experimentally realized several years *** the purpose of quantum communication via this scheme,an entangled ancillary pair shared by Alice and Bob is the essential ingredient,and a quantum memory in Bob’s system is necessary for him to keep the quantum state until the classical message from Alice ***,the quantum memory remains a challenge in both technology and *** we show that quantum teleportation provides fresh perspectives in terms of an alternative scheme for global positioning *** to fixed locations of Bob and Charlie,Alice can determine her relative position by comparing quantum states before and after teleporting around via Bob and Charlie *** may open up a new scene in the stage of the application of quantum physics without quantum memories.

关键词： quantum scheme rational