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利用激光衍射法测量超细丝的直径

大学物理 2024年第7期43卷 46-49页

作者：刘俊周荣浩赵嵩卿中国石油大学(北京)克拉玛依校区文理学院新疆克拉玛依834000 中国石油大学(北京)理学院北京102249

本文介绍了一种根据激光细丝衍射原理测量直径小于12μm超细丝直径的方法.本方法通过对细丝衍射的中央明条纹的衍射强度进行最小二乘法拟合,可获得高精度的细丝直径.本文利用三种不同波长的激光对碳纤维单丝和新疆长绒棉纤维进行实验,... 详细信息

本文介绍了一种根据激光细丝衍射原理测量直径小于12μm超细丝直径的方法.本方法通过对细丝衍射的中央明条纹的衍射强度进行最小二乘法拟合,可获得高精度的细丝直径.本文利用三种不同波长的激光对碳纤维单丝和新疆长绒棉纤维进行实验,利用精度较低的教学光强探测器和智能手机的光传感器收集光强数据,可获得精确的实验结果.

关键词：激光衍射超细丝碳纤维长绒棉智能手机

陆生野生动物布鲁氏菌病的流行与防控研究进展

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动物医学进展 2024年第9期45卷 100-104页

作者：谭学超王勃森郭抗抗姜汹马明筠赵青松湖北三峡职业技术学院湖北宜昌443000 陕西省眉县畜牧兽医技术推广站陕西眉县722300 西北农林科技大学动物医学院陕西杨凌712100

布鲁氏菌病是一种自然疫源性很强的人兽共患传染病,在自然界中存在大量的易感动物和储存宿主。据不完全统计,世界上有60多种野生动物对布鲁氏菌产生血清学反应,30余种野生动物体内寄生了各种布鲁氏菌,这些野生动物可能通过各种传播途径... 详细信息

布鲁氏菌病是一种自然疫源性很强的人兽共患传染病,在自然界中存在大量的易感动物和储存宿主。据不完全统计,世界上有60多种野生动物对布鲁氏菌产生血清学反应,30余种野生动物体内寄生了各种布鲁氏菌,这些野生动物可能通过各种传播途径对人类和家畜造成外溢感染,给防控本病带来极大困难。论文拟对陆生野生动物布鲁氏菌病的流行概况进行综述,分析野生动物传播布鲁氏菌病的潜在风险,提出防控建议,期望能为优化该病综合防控体系和提升整体防疫水平提供参考。

关键词：布鲁氏菌病陆生野生动物布鲁氏菌潜在风险防控

Study on a probabilistic algorithm for the forming and 3D characterization of special-shaped surfaces under profile grinding

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Advances in Manufacturing 2024年第2期12卷 288-299页

作者： zhao-qing Zhang Kai-Ning Shi Yao-Yao Shi Yi-Hui song Zhe He Ya-song Pu School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an710072People’s Republic of China Key Laboratory of High Performance Manufacturing for Aero Engine(Northwestern Polytechnical University) Ministry of Industry and Information TechnologyXi’an710072People’s Republic of China Engineering Research Center of Advanced Manufacturing Technology for Aero Engine(Northwestern Polytechnical University) Ministry of EducationXi’an710072People’s Republic of China

Profile grinding is the most crucial method for the ultra-precision machining of special-shaped ***,profile grinding produces a unique machining profile,and many random factors in the machining process lead to complex surface *** this study,the structural and probabilistic characteristics of the profile grinding of a special-shaped surface were analyzed,and a probabilistic algorithm for the forming and 3D characterization of special-shaped surfaces under profile grinding was *** forming process of a GH738 blade tenon tooth surface was considered as an example to demonstrate the *** comparison results showed that the simulation results had similar surface characteristics to the measurement results,and the relative error range of the 3D roughness parameter was 0.21%–19.76%,indicating an accurate prediction and characterization of the complex special-shaped surface under the action of multiple factors.

关键词： Special-shaped surface Profile grinding Surface morphology 3D characterization

RESEARCH ANNOUNCEMENTS ON“STABILITY OF RAREFACTION WAVES OF THE COMPRESSIBLE NAVIER-STOKES-POISSON SYSTEM WITH LARGE INITIAL PERTURBATION”

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数学杂志 2022年第2期42卷 95-102页

作者： ZHANG Lan zhao Hui-jiang zhao qing-song Center for Mathematical Sciences and Department of Mathematics Wuhan University of TechnologyWuhan 430070China School of Mathematics and Statistics Wuhan UniversityHubei Key Laboratory of Computational ScienceWuhan 430072China

1 Introduction and Main Results In this paper,we study the dynamics of compressible viscous charged particles consisting of two-species particles(e.g.,ions and electrons)under the influence of the self-consistent electrostatic potential force in semiconductor device or plasma physics(cf.[1,6])which is modeled by the compressible Navier-Stokes-Poisson system(called NSP system in the sequel for simplicity).

关键词： compressible system simplicity

Low Surface Brightness Galaxies Selected by Different Model Fitting

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Research in Astronomy and Astrophysics 2024年第1期24卷 223-236页

作者： Bing-qing Zhang Hong Wu Wei Du Pin-song zhao Min He Feng-Jie Lei Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

We present a study of low surface brightness galaxies(LSBGs) selected by fitting the images for all the galaxies inα.40 SDSS DR7 sample with two kinds of single-component models and two kinds of two-component models(disk+bulge):single exponential,single sersic,exponential+deVaucular(exp+deV),and exponential+sérsic(exp+ser).Under the criteria of the B band disk central surface brightness μ_(0,disk)(B)≥22.5 mag arcsec^(-2) and the axis ratio b/a> 0.3,we selected four none-edge-on LSBG samples from each of the models which contain 1105,1038,207,and 75 galaxies,*** are 756 galaxies in common between LSBGs selected by exponential and sersic models,corresponding to 68.42% of LSBGs selected by the exponential model and 72.83% of LSBGs selected by the sersic model,the rest of the discrepancy is due to the difference in obtaining μ_(0) between the exponential and sersic *** on the fitting,in the range of 0.5≤n≤1.5,the relation of μ_(0) from two models can be written as μ_(0,sérsic)-μ_(0,exp)=-1.34(n-1).The LSBGs selected by disk+bulge models(LSBG_(2)comps) are more massive than LSBGs selected by single-component models(LSBG_1comp),and also show a larger disk *** the bulges in the majority of our LSBG_(2)comps are not prominent,more than 60% of our LSBG_(2)comps will not be selected if we adopt a single-component model *** also identified 31 giant low surface brightness galaxies(gLSBGs) from LSBG_(2)*** are located at the same region in the color-magnitude diagram as other *** we compared different criteria of gLSBGs selection,we find that for gas-rich LSBGs,M_(*)> 10^(10)M_⊙ is the best to distinguish between gLSBGs and normal LSBGs with bulge.

关键词： catalogs galaxies:spiral galaxies:bulges methods:data analysis methods:statistical

Relaxation of Chain Extension of Amorphous PET Fiber Above the Glass Transition Temperature

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Chinese Chemical Letters 2000年第10期11卷 925-928页

作者： Xin LINGHU, Jun zhao, Rui song, qing Rong FAN (Polymer Physics Laboratory, Center of Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100080) Polymer Physics Laboratory Center of Molecular Science Institute of Chemistry Beijing 100080 China

The recovery of amorphous PET fiber in global chain orientation but nearly random segmental orientation (GOLR) state was studied by the hot shrinkage measurement above the glass transition temperature. The relaxation curves in the form of di-exponential decay were acquired and the change of two special times with the variation of treating temperature and residual recovery ratio ' was discussed.

关键词： GOLR state PET recovery of chain extension hot shrinkage measurement.

Properties of collective flow and pion production in intermediate-energy heavy-ion collisions with a relativistic quantum molecular dynamics model

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Nuclear Science and Techniques 2024年第1期35卷 155-169页

作者： Si-Na Wei zhao-qing Feng School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

The relativistic mean-field approach was implemented in the Lanzhou quantum molecular dynamics transport model(***). Using the ***, the properties of collective flow and pion production were investigated systematically for nuclear reactions with various isospin asymmetries. The directed and elliptic flows of the *** are able to describe the experimental data of STAR Collaboration. The directed flow difference between free neutrons and protons was associated with the stiffness of the symmetry energy, that is, a softer symmetry energy led to a larger flow difference. For various collision energies, the ratio between the π^(-) and π^(+) yields increased with a decrease in the slope parameter of the symmetry energy. When the collision energy was 270 MeV/nucleon, the single ratio of the pion transverse momentum spectra also increased with decreasing slope parameter of the symmetry energy in both nearly symmetric and neutron-rich ***, it is difficult to constrain the stiffness of the symmetry energy with the double ratio because of the lack of threshold energy correction on the pion production.

关键词： Heavy-ion collision Collective flow Pion production Symmetry energy Relativistic mean field

Chalcone derivatives as novel,potent and selective inhibitors against human Notum:Structure–activity relationships and biological evaluations

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Chinese Chemical Letters 2024年第3期35卷 321-325页

作者： Jin-Hui Shi Bei zhao Li-Lin song Yu-qing song Meng-Ru Sun Tian Tian Hong-Yu Chen Yun-qing song Jian-Ming Sun Guang-Bo Ge Shanghai Frontiers Science Center of TCM Chemical Biology Institute of Interdisciplinary Integrative Medicine Research Shanghai University of Traditional Chinese MedicineShanghai 201203China Dalian Engineering Research Center for Carbohydrate Agricultural Preparations Liaoning Provincial Key Laboratory of CarbohydratesDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine Shanghai 200137China

Human Notum(hNotum)inhibitors could be used for treating Wnt signalling-associated diseases including colorectal ***,two series of chalcone derivatives were designed and synthesized aiming to find selective and potent hNotum ***–activity relationship(SAR)studies showed that 2-methoxyl and 5-bromine substitutions on A-ring significantly enhanced anti-hNotum effect,while 4’-ethoxyl and 3’-alkyl substitutions on B-ring were beneficial for hNotum *** all tested chalcones,B11 displayed the most potent anti-Notum effect(IC_(50)=3.6 nmol/L),good selectivity,excellent chemical stability and suitable metabolic *** investigations showed that B11 acted as a competitive inhibitor of hNotum,while this agent(5μmol/L)significantly weaken the migration abilities of colorectal cancer ***,this study deciphers the SARs of chalcones as hNotum inhibitors and reports a novel and potent hNotum inhibitor with the anti-migration effect on colorectal cancer cells,which offers a promising lead compound to develop novel anti-cancer agents.

关键词： Human notum(hNotum) Chalcone Computer-assisted drug discovery Structure–activity relationship(SAR) Anti-colorectal cancer agent

BBX9 forms feedback loops with PIFs and BBX21 to promote photomorphogenic development

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Journal of Integrative Plant Biology 2024年第9期66卷 1934-1952页

作者： zhaoqing song Wanying Ye qing Jiang Huan Lin qing Hu Yuntao Xiao Yeting Bian Fengyue zhao Jie Dong Dongqing Xu State Key Laboratory of Crop Genetics&Germplasm Enhancement and Utilization National Center for Soybean ImprovementCollege of AgricultureNanjing Agricultural UniversityNanjing 210095China Institute of Crop Science College of Agriculture and BiotechnologyZhejiang UniversityHangzhou 310058China

Light is one of the most essential environmental factors that tightly and precisely control various physiological and developmental processes in plants.B-box CONTAINING PROTEINs(BBXs)play central roles in the regulation of light-dependent *** this study,we report that BBX9 is a positive regulator of light ***9 interacts with the red light photoreceptor PHYTOCHROME B(phyB)and transcription factors PHYTOCHROME-INTERACTING FACTORs(PIFs).phyB promotes the stabilization of BBX9 in light,while BBX9 inhibits the transcriptional activation activity of *** turn,PIFs directly bind to the promoter of BBX9 to repress its *** the other hand,BBX9 associates with the positive regulator of light signaling,BBX21,and enhances its biochemical ***21 associates with the promoter regions of BBX9 and transcriptionally up-regulates its ***,this study unveiled that BBX9 forms a negative feedback loop with PIFs and a positive one with BBX21 to ensure that plants adapt to fluctuating light conditions.

关键词： Arabidopsis BBX21 BBX9 light signaling photo-morphogenesis phyB PIF