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分布式多光谱高温计光学系统设计

光谱学与光谱分析 2024年第1期44卷 230-233页

作者：张南楠陈茜雅常馨方邢键郭佳博崔双龙刘奕彤刘志军东北林业大学信息与计算机工程学院黑龙江哈尔滨150040 哈尔滨工业大学(威海)新能源学院山东威海264209 贵州电子信息职业技术学院贵州凯里556000

多光谱辐射测温技术具有不干扰被测场、测量无上限以及响应速度快等优点,是高温测量领域的最有力工具之一。目前,多光谱高温计以点温测量为主,光路通过物镜、光阑、棱镜等光路通道将待测点辐射分光后进入探测器阵列,实现单点的多光谱信... 详细信息

多光谱辐射测温技术具有不干扰被测场、测量无上限以及响应速度快等优点,是高温测量领域的最有力工具之一。目前,多光谱高温计以点温测量为主,光路通过物镜、光阑、棱镜等光路通道将待测点辐射分光后进入探测器阵列,实现单点的多光谱信息采集。随着工业智能化程度的不断提高,更加需要实时获得大量的温度分布信息,如特种金属材料的冶炼过程、高温合金激光自动焊接过程、半导体晶体生长过程、火箭发动机尾喷焰温度诊断等领域都需要实时获得某条线乃至整个二维表面的温度,从而提高产品性能和质量,因此通过多光谱辐射测温技术测量待测表面某条线的温度分布十分重要。但是,简单将光阑变为狭缝,实现待测线表面的辐射经透镜、棱镜等传统光路分光后,由于光学系统球差的作用,会使得分光后的狭缝光谱由于离轴传输而呈现严重的弯曲现象,不利于矩形光电探测器阵列的完全接收。为此,提出基于正交柱状透镜组的多光谱线温光路系统,利用正交柱状透镜在不同位置成像可以实现由圆到椭圆再到直线的特殊作用,较好地解决了传统多光谱辐射高温计光路所存在的球差问题。利用ZEMAX光学设计软件,基于S4111-16Q的光电探测器阵列实际大小进行反向光学系统设计,确定了狭缝、物镜、棱镜、正交柱状透镜等光学器件关键的参数,基于这些参数所实际加工的光学器件,搭建了多光谱线温高温计光学系统,并进行了无正交柱状透镜和有正交柱状透镜成像情况下的对比实验,结果表明,在没有柱状透镜的情况下,狭缝成像明显弯曲,在加入正交柱状透镜的情况下,狭缝成像弯曲现象消失,经狭缝分光后的线光谱明显呈直线状态,这为整条线的光谱辐射信息完整进入各探测器阵列提供了技术支撑,从而为后续线温测量提供了有力的光谱辐射数据信息。

关键词：多光谱辐射测温光学系统线温测量

高速冲击载荷下WE43镁合金的动态力学响应行为

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塑性工程学报 2024年第8期31卷 147-154页

作者：郭鹏程蒋子涵秦思晓肖罡刘志军柳青中南林业科技大学机电工程学院湖南长沙410004 中国机械总院集团北京机电研究所有限公司北京100083 江西铜业技术研究院有限公司江西南昌330096 江西工业工程职业技术学院机械工程学院江西萍乡337099 豪斯特热冲压技术有限公司广东东莞523507

采用分离式霍普金森压杆和多种显微表征方法研究了两种固溶温度下挤压WE43镁合金的室温动态力学响应行为,应变速率为2580~4120 s^(-1)。结果表明,在高速冲击载荷下,形变孪晶具有较强的正应变速率敏感性,以致流变应力随应变速率的增加而... 详细信息

采用分离式霍普金森压杆和多种显微表征方法研究了两种固溶温度下挤压WE43镁合金的室温动态力学响应行为,应变速率为2580~4120 s^(-1)。结果表明,在高速冲击载荷下,形变孪晶具有较强的正应变速率敏感性,以致流变应力随应变速率的增加而增加。形变孪晶在变形中前期随应变的增加迅速增殖,使得其应变硬化率在应变为0.03~0.10时呈“驼峰”状。基面滑移和孪生相协调是高速冲击载荷下挤压态WE43镁合金的主导塑性变形机制。采用多项式修正了原始J-C本构模型,构建了能够准确描述挤压态WE43镁合金动态力学响应行为的本构模型。本构拟合结果与实验结果的偏差在±10%以内,其相关系数R和平均绝对相对误差e AARE分别为0.962和3.21%。

关键词： WE43镁合金高速冲击力学行为本构建模

镇肝熄风汤对自发性高血压大鼠胆汁酸谱及甾醇12α羟化酶的影响

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中国临床药理学杂志 2024年第15期40卷 2212-2216页

作者：凌必时金华祁尚文刘双芳刘志军甘肃中医药大学中医临床学院甘肃兰州730000 甘肃中医药大学附属医院神经内科甘肃兰州730000

目的观察镇肝熄风汤对自发性高血压大鼠(SHR)胆汁酸谱及甾醇12α羟化酶(CYP8B1)的影响。方法将50只SHR随机分为模型组、对照组(灌胃1.0 mg·kg^(-1)·d^(-1)贝那普利)和低、中、高剂量实验组(灌胃镇肝熄风汤8.63、17.25、34.50 g·kg^(... 详细信息

目的观察镇肝熄风汤对自发性高血压大鼠(SHR)胆汁酸谱及甾醇12α羟化酶(CYP8B1)的影响。方法将50只SHR随机分为模型组、对照组(灌胃1.0 mg·kg^(-1)·d^(-1)贝那普利)和低、中、高剂量实验组(灌胃镇肝熄风汤8.63、17.25、34.50 g·kg^(-1)·d^(-1));另取10只同源雄性京都Wistar大鼠作为正常组。模型组和正常组均灌胃给予等量蒸馏水。6组大鼠每天给药1次,连续给药8周。用动物无创血压计以尾套法测量各组大鼠血压,用UPLC-MS/MS法检测各组大鼠胆汁酸谱,用实时荧光定量聚合酶链反应法检测大鼠肝组织中CYP8B1 mRNA的表达情况。结果中、高剂量实验组和对照组、模型组、正常组的第8周收缩压分别为(169.63±12.10)、(170.32±9.64)、(175.95±15.47)、(189.47±7.42)和(146.40±9.45)mmHg,第8周舒张压分别为(135.10±11.99)、(129.73±15.10)、(135.18±17.62)、(149.20±8.83)和(110.53±10.92)mmHg,CYP8B1 mRNA相对表达水平分别为3.36±0.94、5.45±1.46、4.29±0.95、0.89±0.14和1.00±0.00。中、高剂量实验组的上述指标与模型组比较,在统计学上差异均有统计学意义(P<0.01,P<0.05)。低、中、高剂量实验组与模型组比较,胆汁酸谱改变明显,共发现9种差异胆汁酸,分别为猪去氧胆酸、甘氨猪去氧胆酸、甘氨鹅去氧胆酸、甘氨熊去氧胆酸、α-鼠胆酸、熊去氧胆酸、胆酸、β-鼠胆酸、甘氨胆酸。结论镇肝熄风汤可能通过上调肝CYP8B1表达,纠正胆汁酸谱紊乱,从而达到降低血压的目的。

关键词：镇肝熄风汤高血压胆汁酸谱胆汁甾醇12α羟化酶

Mesoscopic measurement of damage and shear bands of granite residual soil using Micro-CT and digital volume correlation

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Journal of Mountain Science 2023年第11期20卷 3423-3436页

作者： LI Cheng-sheng ZHANG Bing-xin liu zhi-jun KONG Ling-wei SHU Rong-jun Department of Civil and Environmental Engineering Shantou UniversityShantou 515000China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChineseAcademy of SciencesWuhan 430000China College of Civil and Architecture Engineering Chuzhou UniversityChuzhou 239000China

The mesomechanics of geotechnical materials are closely related to the macromechanical properties,especially the mesoscale evolution of shear bands,which is helpful for understanding the failure mechanism of geotechnical ***,there is lack of effective quantitative analysis method for the complex evolution mechanism of threedimensional shear *** this work,we used X-ray computed tomography(CT)to reconstruct volume images and used the digital volume correlation(DVC)method to calculate the three-dimensional strain fields of granite residual soil samples at different loading *** trend of the failure surface of the shear bands was obtained by the planar fitting method,and the connectivity index was constructed according to the projection characteristics of the shear bands on the failure trend *** results support the following findings:the connectivity index of the shear band increases rapidly and then slowly with increasing axial strain,which is characterized by a near'S'*** the stress reaches the peak value,the connectivity index of the shear bands almost exceeds *** contribution of the new shear band volume to the connectivity of the shear bands becomes increasingly small with increasing axial *** by quartz grains and stress at the initial stage,the dip angle gradually and finally approaches the included angle of the maximum shear stress from the discrete state with increasing axial *** tendency and dip angle of the resulting shear bands are dynamic,and the tendency slightly deflects with increasing loading.

关键词： Damage Shear band Digital volume correlation Micro-CT Granite residual soil

Experimental observations of ferroelectricity in double pyrochlore Dy2Ru2O7

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Frontiers of physics 2014年第1期9卷 82-89页

作者： Zai-Chun Xu Mei-Feng liu Lin Lin Huimei liu zhi-Bo Yan jun-Ming liu Laboratory of Solid State Microstructures Nanjing University Nanjing 210093 China

Double pyrochlore Dy2Ru207 is synthesized and its magnetism and ferroelectricity below the Ru4＋ spin ordering temperature （NI00 K） are investigated. The ferroelectric transition appears at -18 K, much higher than the Dy3＋ spin ordering point at -1.8 K and lower than the Ru4＋ spin ordering point at -100 K. The measured electric polarization at ,-2 K is as big as 145℃/m2 in the polycrystalline samples. It is argued that the ferroelectricity is possibly ascribed to the electric dipole ordering arising from the collective monopole excitations in the Dy3＋ tetrahedrons in prior to the Dy3＋ spin ordering into spin-ice like state below -1.8 K.

关键词： pyrochlore oxides multiferroics magnetically induced ferroelectricity

Equivalence between the internal observability and equation

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 89-97页

作者： liu Wen-jun TU zhi-yu School of Mathematics and Statistics Nanjing University of Information Science and TechnologyNanjing 210044China

This paper is concerned with a third order in time linear Moore-Gibson-Thompson equation which describes the acoustic velocity potential in ultrasound wave *** by the work of Kaltenbacher,Lasiecka and Marchand(Control Cybernet.2011,40:971-988),we establish an observability inequality of the conservative problem,and then discuss the equivalence between the exponential stabilization of a dissipative system and the internal observational inequality of the corresponding conservative system.

关键词： Moore-Gibson-Thompson equation internal observability exponential stability

Quasi-2D weak lensing cosmological constraints using the PDF-SYM method

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 44-58页

作者： Zhenjie liu jun Zhang Hekun Li zhi Shen Cong liu Department of Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory for Particle Physics and Cosmology Shanghai 200240China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China

Cosmic shear statistics,such as the two-point correlation function(2PCF),can be evaluated with the PDF-SYM method instead of the traditional weighted-sum *** makes use of the full PDF information of the shear estimators,and does not require weightings on the shear estimators,which can in principle introduce additional systematic *** work presents our constraints on S8and?mfrom the shear-shear correlations using the PDF-SYM *** data we use is from the z-band images of the Dark Energy Camera Legacy Survey(DECa LS),which covers about 10000 deg2with more than 100 million *** shear catalog is produced by the Fourier Quad method,and well tested on the real data itself with the field-distortion *** main approach is called quasi-2D as we do use the photo-z information of each individual galaxy,but without dividing the galaxies into redshift *** mainly use galaxy pairs within the redshift interval between 0.2 and 1.3,and the angular range from 4.7 to 180 *** analysis yields S8=0.762±0.026 and?m=0.234±0.075,with the baryon effects and the intrinsic alignments *** results are robust against redshift *** check the consistency of our results by deriving the cosmological constraints from auto-correlations ofγ1andγ2separately,and find that they are consistent with each other,but the constraints from theγ1component are much weaker than that fromγ*** implies a much worse data quality ofγ1,which is likely due to additional shear uncertainties caused by CCD electronics(according to the survey strategy of DECa LS).We also perform a pure 2D analysis,which gives S8=0.81_(-0.04)^(+0.03)and?m=0.25_(-0.05)^(+0.06).Our findings demonstrate the potential of the PDF-SYM method for precision cosmology.

关键词： weak lensing shear-shear correlations cosmological parameters observations analysis

基于工程教育专业认证的毕业设计校企协同教学模式探索——以中国矿业大学道路与桥梁工程方向为例

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教育教学论坛 2024年第6期 128-131页

作者：王亮亮张营营柳志军中国矿业大学力学与土木工程学院江苏徐州221116

在产出导向教育教学体系中,毕业设计是学生在校培养环节中的汇总点,对专业培养目标的达成具有重要影响。在分析工程教育专业认证标准对毕业设计的要求的基础上,结合学校道路与桥梁工程专业现行毕业设计中存在的问题,按照毕业设计校企协... 详细信息

在产出导向教育教学体系中,毕业设计是学生在校培养环节中的汇总点,对专业培养目标的达成具有重要影响。在分析工程教育专业认证标准对毕业设计的要求的基础上,结合学校道路与桥梁工程专业现行毕业设计中存在的问题,按照毕业设计校企协同教学基地建设、设计成果共享、校企“双导师”职责划分与指导方式、成绩评定方案及选题遴选机制的思路,对毕业设计教学模式进行了探索,对促进校企毕业设计合作长期健康稳定发展、持续改进和培养目标达成具有借鉴意义。

关键词：工程教育专业认证培养目标土木工程持续改进

Automatic extraction and structuration of soil–environment relationship information from soil survey reports

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Journal of Integrative Agriculture 2019年第2期18卷 328-339页

作者： WANG De-sheng liu jun-zhi ZHU A-xing WANG Shu ZENG Can-ying MA Tianwu Key Laboratory of Virtual Geographic Environment Nanjing Normal UniversityNanjing 210023P.R.China State Key Laboratory Cultivation Base of Geographical Environment Evolution(Jiangsu Province) Nanjing 210023P.R.China Jiangsu Center for Collaborative Innovation in Geographic Information Resource Development and Application Nanjing 210023P.R.China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China Department of Geography University of Wisconsin-MadisonMadisonWI 53706USA

In addition to soil samples, conventional soil maps, and experienced soil surveyors, text about soils(e.g., soil survey reports) is an important potential data source for extracting soil–environment relationships. Considering that the words describing soil–environment relationships are often mixed with unrelated words, the first step is to extract the needed words and organize them in a structured way. This paper applies natural language processing(NLP) techniques to automatically extract and structure information from soil survey reports regarding soil–environment relationships. The method includes two steps:(1) construction of a knowledge frame and(2) information extraction using either a rule-based method or a statistic-based method for different types of information. For uniformly written text information, the rule-based approach was used to extract information. These types of variables include slope, elevation, accumulated temperature, annual mean temperature, annual precipitation, and frost-free period. For information contained in text written in diverse styles, the statistic-based method was adopted. These types of variables include landform and parent material. The soil species of China soil survey reports were selected as the experimental dataset. Precision(P), recall(R), and F1-measure(F1) were used to evaluate the performances of the method. For the rule-based method, the P values were 1, the R values were above 92%, and the F1 values were above 96% for all the involved variables. For the method based on the conditional random fields(CRFs), the P, R and F1 values for the parent material were, respectively, 84.15, 83.13, and 83.64%; the values for landform were 88.33, 76.81, and 82.17%, respectively. To explore the impact of text types on the performance of the CRFs-based method, CRFs models were trained and validated separately by the descriptive texts of soil types and typical profiles. For parent material, the maximum F1 value for the descriptive text

关键词： soil–environment relationship text natural language processing extraction structuration