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基于图像结构信息的可见光和SAR图像快速配准

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系统工程与电子技术 2024年

作者：贾蕾蕾刘利民董健 1.陆军工程大学石家庄校区电子与光学工程系 2.北京理工大学集成电路与电子学院陆军工程大学石家庄校区电子与光学工程系北京理工大学集成电路与电子学院

针对可见光和合成孔径雷达（synthetic aperture radar，SAR）图像配准过程中的几何差异、辐射差异和斑点噪声问题，提出一种基于图像结构信息的可见光和SAR图像快速配准算法。首先，建立高斯尺度空间，利用偏移均值滤波和双线性插值建... 详细信息

针对可见光和合成孔径雷达（synthetic aperture radar，SAR）图像配准过程中的几何差异、辐射差异和斑点噪声问题，提出一种基于图像结构信息的可见光和SAR图像快速配准算法。首先，建立高斯尺度空间，利用偏移均值滤波和双线性插值建立图像自相似性方向图；然后，在最大和最小自相似性图上进行FAST特征点检测，获取角点和边缘特征；再者，基于最小自相似性索引图和等面积策略构建描述子，并提出描述子多方向转换方法和批量生成方法；最后，利用最近邻与次近邻之比和快速抽样一致性识别正确匹配。实验结果表明，该算法在可见光和SAR图像配准方面具有明显优势。

关键词：可见光和SAR图像配准结构信息多方向转换批量生成

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超重力-微界面法制备类球形纳米碳酸钙

化工进展 2024年

作者：孙金磊廖丹葵陈小鹏童张法 1.广西大学化学化工学院 2.广西碳酸钙产业化工程院有限公司

以聚乙烯亚胺（PEI）为晶型控制剂、甲醇为分散剂、氢氧化钙溶液和CO2.原料，采用超重力-微界面法进行类球形纳米碳酸钙制备研究。利用高速摄像机对反应器中气泡粒径进行分析；考察反应温度、CO2.量、氢氧化钙溶液浓度、甲醇体积分数... 详细信息

以聚乙烯亚胺（PEI）为晶型控制剂、甲醇为分散剂、氢氧化钙溶液和CO2.原料，采用超重力-微界面法进行类球形纳米碳酸钙制备研究。利用高速摄像机对反应器中气泡粒径进行分析；考察反应温度、CO2.量、氢氧化钙溶液浓度、甲醇体积分数、PEI添加量对碳酸钙产物形貌的影响；应用正交实验方法优化氢氧化钙碳化反应条件；利用SEM、XRD和FT-IR分析方法对反应产物的形貌进行了表征。结果表明，超重力-微界面碳化反应器可以将CO2.泡由毫米级高效转化为微米级，增大了气液相界面积，提高了气液传质；氢氧化钙与CO2.化反应最佳反应条件是氢氧化钙浓度为8%、 PEI添加量为氢氧化钙质量的4%、甲醇体积分数为2.%、CO2.量为2.5L/min、反应温度为12.，所制备的类球形纳米碳酸钙粒径为40nm～60nm。

关键词：类球形纳米碳酸钙超重力微界面气泡传质

Numerical simulation of Meiyu front and the diagnosis of moist vorticity vector

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Progress in Natural Science:Materials International 2007年第11期17卷 1341-1347页

作者： Ping Fan1,2.and Luo Zhexian2.1. Institute of Atmospheric physics, Chinese Academy of Sciences, Beijing 10002., china 2. Nanjing University of Information Sciences & Technology, Nanjing 2.0044, china) Institute of Atmospheric physics Chinese Academy of Sciences Beijing 100029 China Nanjing University of Information Sciences & Technology Nanjing 210044 China

Moist vorticity vector is introduced to study the development and evolution of mesoscale convective vortex (MCV) in the Meiyu front precipitation with the Advanced Regional Predication System (ARPS). In this study, the heavy rainfall is simulated to investigate the genesis, development and dissipation of middle scale convective vortex, which occurred from 0000 UTC 3 July to 12.0 UTC 5 July over the Jianghuai River valley. Moist vorticity vector (MVV) has zonal, radial and vertical components in its 3D spatial distribution. The simulation shows that the vertical component of moist vorticity vector well demonstrates the spatial distribution characteristics of middle scale convective vortex, especially in the process of Meiyu front precipitation. Diagnosis upon zonal, radial averaged and mass-integrated quantities of MVV shows that its vertical component and the surface precipitating ratio are in phase with a correlation coefficient of 0.68, indicating that the vertical component of MVV is closely associated with the Meiyu front precipitation. In addition, the tendency of the vertical component of MVV is mainly determined by the interaction between the vorticity and the zonal and radial gradient of condensational or depositional heating.

关键词： moist vorticity vector mesoscale convective vortex Meiyu front precipitation

基于代谢组学探究牛至精油对绵羊直肠粪便代谢物的影响

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草业科学 2024年

作者：宋淑珍刘立山周瑞 1.甘肃省农业科学院畜草与绿色农业研究所 2.西北民族大学生命与工程学院甘肃省农业科学院畜草与绿色农业研究所西北民族大学生命与工程学院

本试验旨在研究饲喂牛至精油对绵羊粪便代谢物的影响。选择体重接近[（2..00±1.2.）kg]的萨福克与小尾寒羊杂交公羔12.，随机分为2.，每组6只羊。分别为对照组、牛至精油组。对照组饲喂基础饲粮，牛至精油组饲喂基础饲粮+7 g·d-1·... 详细信息

本试验旨在研究饲喂牛至精油对绵羊粪便代谢物的影响。选择体重接近[（2..00±1.2.）kg]的萨福克与小尾寒羊杂交公羔12.，随机分为2.，每组6只羊。分别为对照组、牛至精油组。对照组饲喂基础饲粮，牛至精油组饲喂基础饲粮+7 g·d-1·只-1牛至精油。预试期10 d，正式期72.d。试验期结束后，采集直肠粪便进行液相色谱-串联质谱法（liquid chromatography-tandem mass spectrometry，LC-MS/MS）非靶向代谢组学技术筛选差异代谢物。结果表明：1)两组试验羊的粪便中正、负离子模式共筛选出甲基-2.3-O-二烯丙基-4，6-O-亚苄基-alpha-D-吡喃甘露糖苷、二十二碳-4，7，10，13，16-五烯酸酯、甲基胍、腺嘌呤、18：1碳链溶血磷脂酰乙醇胺、N-乙酰-D-神经氨酸、环己烷羧酸、4-甲氧基苯乙酸、DL-多巴、胸腺嘧啶、去甲氧基姜黄素、5’-甲基硫代腺苷、间羟基苯甲酸等15种差异代谢物（∣LogFC∣>1，P1），且与对照组相比，牛至精油组的差异代谢物全部上调。2.差异代谢物KEGG通路富集到萜类和类固醇的合成，微生物代谢，苯丙氨酸、酪氨酸和色氨酸的合成，半胱氨酸和蛋氨酸代谢、芳香族化合物的降解等6条通路（Impact>0.1），分别归属于脂质代谢，消化道微生物代谢和氨基酸代谢。这表明，牛至精油可能参与育肥羊脂质代谢、有机物代谢和氨基酸代谢，通过调节代谢途径发挥其在羊养殖中的健康维护作用。

关键词：牛至精油羊微生物代谢氨基酸代谢

Adjoint method for the optimum planning of industrial pollutant sources

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Science china Earth Sciences 2005年第8期48卷 1270-1279页

作者： LIU Feng1,2. HU Fei2.& ZHU Jiang2.1. College of Environmental Sciences, Peking University, Beijing 100871, china 2. LAPC, Institute of Atmospheric physics, Chinese Academy of Sciences, Beijing 10002., china 1. College of Environmental Sciences Peking University 100871 Beijing China 2. LAPC Institute of Atmospheric Physics Chinese Academy of Sciences 100029 Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.

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植物叶面吸收有机污染物机理研究进展

农业环境科学学报 2024年

作者：刘宪斌衣新悦刘青 1.天津科技大学海洋与环境学院 2.天津市海洋环境保护与修复技术工程中心天津科技大学海洋与环境学院天津市海洋环境保护与修复技术工程中心

植物是有机污染物的重要储存体。有机污染物可以跨叶面进入植物体，通过食物链的富集作用，造成潜在的环境和健康风险。气孔和角质层是叶面吸收有机污染物的两个主要途径，角质层作为典型的大气-植物体微界面，是植物和大气中有机污染... 详细信息

植物是有机污染物的重要储存体。有机污染物可以跨叶面进入植物体，通过食物链的富集作用，造成潜在的环境和健康风险。气孔和角质层是叶面吸收有机污染物的两个主要途径，角质层作为典型的大气-植物体微界面，是植物和大气中有机污染物的双向运输障碍。相对于气孔的直接吸收，有机污染物在角质层上的跨膜行为更加复杂。本文总结了有机污染物的叶面吸收途径，综述了有机污染物的叶面吸收机理及影响因素，重点阐述了有机污染物跨角质层的运输过程，并展望了未来的研究趋势和发展方向，为更好了解有机污染物的叶面吸收机理及其在环境中的归趋行为提供理论基础。

关键词：叶面吸收角质层气孔有机污染物

Studies on the microstructure,optical and electrical properties of organic microcavity devices based on a porous silicon reflector

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Science china(Technological Sciences) 2005年第2期48卷 191-201页

作者： XIONG Zuhong1, FAN Yongliang2. ZHAN Yiqiang2. ZHANG Songtao2. DING Xunmin2.& HOU Xiaoyuan2.1. School of physics, Southwest china-Normal University, Chongqing 400715, china 2. Surface physics Laboratory (National Key Laboratory), Fudan University, Shanghai 2.0433, china 1. School of physics Southwest China-Normal University 400715 Chongqing China 2. Surface physics Laboratory (National Key Laboratory) Fudan University 200433 Shanghai China

A novel type of microcavity organic light-emitting diode based on a porous silicon distributed Bragg reflector (PS-DBR) has first been achieved and its microstructure, optical, and electrical properties have also been investigated in detail. The microcavity is made up of the central active organic multilayer sandwiched between a top silver film and a bottom PS-DBR, formed by electrochemical etching of p++-Si substrate. The field- emission scanning electron microscopy cross-section images show the nanometer-scale layered structure and flat interfaces inside the microcavity. The reflectivity (relative to an Al mirror) of the PS-DBR is up to 99%, and the stopband is about 160 nm wide. Resonant cavity mode appears as a tip in the reflectivity spectrum of the Si-based organic multilayer films, which is a symbol that the Si-based organic multilayer structure is indeed a microcavity. The peak widths of the electroluminescence (EL) spectra from the cavities emitting green and red light are greatly reduced from 85 nm and 70 nm to 8 nm and 12.nm, respectively, as compared with those measured from non-cavity structures. Note that the EL emission from the cavity devices is single-mode, and the off-resonant optical modes are highly suppressed. Moreover, increases of a factor of about 6 and 4 of the resonant peak intensity from the cavities emitting green and red light are also observed, respectively. In addition, the current-brightness-voltage characteristics and effect parameters on the lifetime of the cavity devices are also discussed. The present technique for obtaining enhanced EL emission from Si-based organic microcavity may also be another novel effective method for realizing Si-based optoelectronics device integration.

关键词： electrochemical etching, Si-based microcavity, electroluminescence, organic light-emitting diodes.

Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1,2.and Li Jianping2.1. College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, china 2. LASG, Institute of Atmospheric physics, Chinese Academy of Sciences, Beijing 10002., china) College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1948—2.05. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1976. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

山西省科学技术厅山西省财政厅关于印发《省科技创新券实施管理办法》的通知(晋科发〔2.2.〕16号)

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山西省人民政府公报 2024年第5期 55-58页

作者： 1.山西省科学技术厅 2.山西省财政厅山西省科学技术厅山西省财政厅

各市科技局、财政局,各有关单位:为进一步促进科研设施与仪器等科技资源开放共享,降低中小微企业创新投入成本,盘活全省科技创新资源,激发全社会创新创业潜能,促进产学研合作,提高创新水平,支持经济社会高质量发展,省科技厅、省财政厅... 详细信息

各市科技局、财政局,各有关单位:为进一步促进科研设施与仪器等科技资源开放共享,降低中小微企业创新投入成本,盘活全省科技创新资源,激发全社会创新创业潜能,促进产学研合作,提高创新水平,支持经济社会高质量发展,省科技厅、省财政厅共同研究制定了《省科技创新券实施管理办法》。现印发给你们,请认真贯彻执行。

关键词：山西省财政厅科学技术厅科技创新券产学研合作科研设施科技创新资源开放共享实施管理办法