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溯源于空间低温绝对辐射计的太阳反射谱段基准载荷研究进展(特邀)

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光学学报 2024年第18期44卷 100-113页

作者：叶新方伟胡秀清张亚超衣小龙李博徐楠全加孙德王玲唐洪钊桂利佳中国科学院长春光学精密机械与物理研究所空间光学研究一部吉林长春130033 中国气象局中国遥感卫星辐射测量和定标重点开放实验室国家卫星气象中心(国家空间天气监测预警中心)北京100081 中国计量科学研究院光学与激光计量科学研究所北京100029 中国科学院理化技术研究所中国科学院空间功热转换技术重点实验室北京100190 长春工业大学化学工程学院吉林长春130012 自然资源部国土卫星遥感应用中心北京100844 上海卫星工程研究所热控工程技术研究室上海201109

为有效检测全球气候变化信号,准确预测气候变化,太阳反射谱段的空间遥感数据必须长期保持在0.3%的不确定度水平。然而,受遥感载荷定标系统设计以及地面辐射校正技术理论极限限制,太阳反射谱段的辐射定标停留在2%的不确定度水平,难以完... 详细信息

为有效检测全球气候变化信号,准确预测气候变化,太阳反射谱段的空间遥感数据必须长期保持在0.3%的不确定度水平。然而,受遥感载荷定标系统设计以及地面辐射校正技术理论极限限制,太阳反射谱段的辐射定标停留在2%的不确定度水平,难以完全满足气候研究需求。为解决这一难题,中国、欧洲国家和美国同期提出发展溯源于低温绝对辐射计的太阳反射谱段基准载荷,分别搭载于各自的空间辐射基准卫星(LIBRA、TRUTHS和CLARREO),以提升太阳反射谱段遥感数据测量精度。本文重点介绍了太阳反射谱段基准载荷的研究进展。首先,介绍了中国、欧洲国家和美国的空间辐射基准载荷的发展思路和现状,对比了TRUTHS、CLARREO和LIBRA计划的太阳反射谱段基准载荷设计方案的优劣;然后,详细介绍了中国科学院长春光学精密机械与物理研究所在太阳反射谱段基准载荷研究方面取得的重要进展;最后,对太阳反射谱段基准载荷的研究进展进行讨论与展望。

关键词：空间低温绝对辐射计太阳反射谱段成像光谱仪辐射定标基准载荷

Excitatory effect of histamine on neuronal activity of rat cerebellar fastigial nucleus in vitro

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Chinese Science Bulletin 2007年第4期52卷 497-503页

作者： tang Biao ZHANG Jun LI hongzhao ZHU JingNing WANG JianJun Department of Biological Science and Technology/State Key Laboratory of Pharmaceutical Biotechnology School of Life Sciences Nanjing University Nanjing 210093 China Jiangsu Key Laboratory for Bioresource Technology School of Life Sciences Nanjing Normal University Nanjing 210097 China

The cerebellar fastigial nucleus (FN) holds an important role in motor control and body balance. Previous studies have revealed that the nucleus is innervated by direct hypothalamocerebellar histaminergic fibers. However, the functional role of histaminergic projection in cerebellar FN has never been established. In this study, we investigated the effect of histamine on neuronal firing of cerebellar FN by using slice preparations. Sixty-five FN cells were recorded from 47 cerebellar slices, and a vast majority of the cells responded to histamine stimulation with an excitatory response (58/65, 89.2%). Perfusing slices with low-Ca2+/high-Mg2+ medium did not block the histamine-induced excitation (n=10), supporting a direct postsynaptic action of histamine on the cells. Furthermore, the excitatory effect of histamine on FN neurons was not blocked by selective histamine H1 receptor antagonist triprolidine (n=15) or chlorpheniramine (n=10), but was effectively suppressed by ranitidine (n=15), a highly selective histamine H2 receptor antagonist. On the other hand, highly selective histamine H2 receptor agonist dimaprit (n=20) instead of histamine H1 receptor agonist 2-pyridylethylamine (n=16) mimicked the ex- citatory effect of histamine on FN neurons. The dimaprit-induced FN neuronal excitation was effectively antagonized by selective histamine H2 receptor antagonist ranitidine (n=13) but not influenced by se- lective histamine H1 receptor antagonist triprolidine (n=15). These results demonstrate that histamine excites cerebellar FN cells via the histamine H2 receptor mechanism and suggest that the hypotha- lamocerebellar histaminergic fibers may modulate cerebellar FN-mediated sensorimotor integration through their excitatory innervations on FN neurons.

关键词：大鼠小脑顶核神经活动组胺受体兴奋作用

Type 1 T-cell responses in chlamydial lung infections are associated with local MIP-1a response

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Cellular & Molecular Immunology 2010年第5期7卷 355-360页

作者： Naihong Zhang Zhaoe Wang Xiaofei tang Haiping Wang hongzhao Li Huanjun Huang Hong Bai Xi Yang Department of Immunology Tianjin Medical UniversityTianjin Key Laboratory of Cellular and Molecular ImmunologyKey Laboratory of Educational Ministry of ChinaTianjinChina Laboratory for Infection and Immunity Departments of Medical Microbiology and ImmunologyFaculty of MedicineUniversity of ManitobaWinnipegManitobaCanada

Chemokines and their receptors are important mediators of leukocyte trafficking and recruitment and sometimes work as modulators of T-cell responses during infections and *** the biological activity of chemokines has been found to influence the course of ***,little is known about the role of chemokine responses during chlamydial lung *** therefore analyzed the dynamics of multiple chemokines,which are frequently associated with type 1(Th1)T cell immune responses,and their receptors for their expression in the lungs during Chlamydia muridarum(Cm)*** also examined the relationship between chemokine responses and the development of Th1 responses as well as the clearance of *** results showed that in parallel with the high levels of gamma interferon(IFN-c)and IL-12 production in the lungs and draining lymph nodes,and the expansion of IFN-c-producing CD4 and CD81 T cells,the production of the cell-related chemokines RANTES,IFN-c-inducible protein-10(IP-10)and macrophage inflammatory protein-1a(MIP-1a)and their receptor CCR1 was elevated in the lung tissues after ***,in a later phase of infection,the expression of RANTES and IP-10 remained elevated but the expression of MIP-1a and CCR1 decreased to a low level,which suggests a closer association with the pattern of Th1 cytokine responses in the process of *** results suggest a close association between the MIP-1a response and the Th1-type T-cell responses in chlamydial lung infections .

关键词： Chlamydial pneumonia MIP-1a RANTES Th1 response

Genesis of the Nuri Cu-W-Mo Deposit,Tibet,China:Constraints from in situ Trace Elements and Sr Isotopic Analysis of Scheelite

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 117-131页

作者： WANG Yiyun WU Zhishan CHEN Wenqing DU Qing’an tang Liwei SHI hongzhao MA Guotao ZHANG Zhi LIANG Wei WU Bo MIAO Hengyi Chengdu Center China Geological Survey(Geoscience Innovation Center of Southwest China)Chengdu 610081China The Second Geological Institute of China’s Metallurgical Geology Bureau Fuzhou 351111China

The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,***,the genetic type of this deposit has been controversial since its *** on a study of the geological characteristics of the deposit,this study presents mineralization stages,focusing on the oxide stage and the quartz-sulfide stage where scheelite is mainly formed,referred to as Sch-A and Sch-B,*** LA-ICP-MS trace element and Sr isotope analyses,the origin,evolutionary process of the oreforming fluid and genesis of the ore deposit are *** Electron Microscope-Cathodoluminescence(SEMCL)observations reveal that Sch-A consists of three generations,with dark gray homogenous Sch-A1 being replaced by relatively lighter and homogeneous Sch-A2 and Sch-A3,with Sch-A2 displaying a gray CL image color with vague and uneven growth bands and Sch-A3 has a light gray CL image color with hardly any growth *** contrast,Sch-B exhibits a‘core-rim’structure,with the core part(Sch-B1)being dark gray and displaying a uniform growth band,while the rim part(Sch-B2)is light gray and *** normalized distribution pattern of rare earth elements in scheelite and Sr isotope data suggest that the early ore-forming fluid in the Nuri deposit originated from granodiorite porphyry and,later on,some country rock material was mixed in,due to strong water-rock *** the O-H isotope data further indicates that the ore-forming fluid in the Nuri deposit originated from magmatic-hydrothermal sources,with contributions from metamorphic water caused by water-rock interaction during the mineralization process,as well as later meteoric *** intense water-rock interaction likely played a crucial role in the precipitation of scheelite,leading to varying Eu anomalies in different generations of scheelite from the oxide stage to the quartz-sulfide stage,while also causing a

关键词： trace elements in situ Sr isotopes tungsten mineralization Gangdese metallogenic belt Tibet

Deep eutectic solvent-based gel electrolytes for flexible electrochromic devices with excellent high/low temperature durability

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InfoMat 2023年第2期5卷 11-21页

作者： Peiyan Sun Jian Chen Yaowu Li Xueqing tang hongzhao Sun Ge Song Xinyang Mu Taoyang Zhang Xiuling Zha Feifan Li Yanfeng Gao Shan Cong Zhigang Zhao School of Materials Science and Engineering Shanghai UniversityShanghaiPeople's Republic of China Key Lab of Nanodevices and Applications Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhouChina

With the increasing interest in the application of electrochromism to flexible and wearable electronics in recent years,flexible electrochromic devices(ECDs)that can function at extreme temperatures are ***,the functionalities of flexible ECDs are severely hampered by the inadequate choice of electrolytes,which might ultimately result in performance fading during low-and high-temperature ***,we develop a deep eutectic solvent(DES)-based gel electrolyte that can maintain its optical,electrical,and mechanical properties over a wide range of temperatures(-40 to 150℃),exhibiting an extremely high visible-range transmittance over 90%,ion conductivity of 0.63 mS cm^(-1),and fracture strain exceeding 2000%.Owing to the excellent processability of the DES-based electrolytes,provided by dynamic interactions such as the lithium and hydrogen bonding between the DES and polymer matrix,a directly written patterning in ECDs is realized for the first *** fabricated ECDs exhibit an excellent electrochromic behavior superior to the behavior of the ECDs fabricated with traditional gel *** introduction of such DES-based electrolytes is expected to pave the way for a widespread application of electrochromic products.

关键词： deep eutectic solvent direct writing electrolyte flexible electrochromic devices temperature durability

基于遗传-模式搜索算法的微尺度管控区域大气污染物PM2.5溯源

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浙江大学学报（工学版） 2024年第6期58卷 1296-1304页

作者：董红召金灿唐伟佘翊妮林盈盈浙江工业大学智能交通系统研究所浙江杭州310014 杭州市生态环境科学研究院浙江杭州310014

针对微尺度管控区域可能发生的大气污染提出有效的靶向诊断方法-结合高斯烟羽模型和遗传-模式搜索算法的大气污染物分布式溯源方法.将污染源反算模型得到的污染物理论质量浓度与传感器网络观测值的数据对应关系作为目标函数,使用模式搜... 详细信息

针对微尺度管控区域可能发生的大气污染提出有效的靶向诊断方法-结合高斯烟羽模型和遗传-模式搜索算法的大气污染物分布式溯源方法.将污染源反算模型得到的污染物理论质量浓度与传感器网络观测值的数据对应关系作为目标函数,使用模式搜索算法嵌入遗传算法加快反算模型的搜索过程,反算得到污染源强度和位置.依托杭州市亚运板球场馆大气感知器网络进行实验验证,监测2021年10月PM2.5质量浓度、气象数据,对所提出的混合式大气污染溯源方法进行实验验证.实验结果表明:改进遗传-模式搜索算法对于多维变量的搜索效果较好,能快速精准地反算污染源的位置和强度,可以为微尺度管控区域突发性气体污染防治提供应急决策参考.

关键词：源强反算遗传-模式搜索算法高斯烟羽模型微尺度管控颗粒物污染溯源

基于改进的超球支持向量机的有杆抽油泵故障诊断研究

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机械科学与技术 2011年第1期30卷 133-137,141页

作者：王凯刘宏昭熊俊唐小彪西安理工大学机械及精密仪器学院西安710048 成都理工大学信息工程学院成都610059 四川省煤田地质局137队达州635000

针对神经网络对有杆抽油泵系统进行故障诊断存在的缺陷以及支持向量机在大规模训练样本或训练样本严重不平衡时的多分类问题求解中能效不足,提出了基于改进分类策略的超球支持向量机多分类算法。赋予3种工作集选择方式的贯序最小优化算... 详细信息

针对神经网络对有杆抽油泵系统进行故障诊断存在的缺陷以及支持向量机在大规模训练样本或训练样本严重不平衡时的多分类问题求解中能效不足,提出了基于改进分类策略的超球支持向量机多分类算法。赋予3种工作集选择方式的贯序最小优化算法用于支持网格搜索模型以便进行参数寻优,避免了参数选择的盲目性和随意性。根据训练样本规模适时引入核缓存技术和上三角矩阵策略,使得寻优耗时减少。开发了基于Java语言、功能完备的超球支持向量机工具箱HSSVM-1.17。利用HSSVM-1.17对抽油泵工况进行了多分类仿真试验,并与BP神经网络、支持向量机方法加以比较。试验结果表明:改进后的超球支持向量机算法理论严谨、参数寻优迅速、分类精度高、自适应好,适用于采油工程领域中大规模复杂的故障诊断问题。

关键词：超球支持向量机分类策略参数寻优核缓存技术

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高导热金刚石/铜复合材料的导热研究进展

稀有金属材料与工程 2020年第12期49卷 4146-4158页

作者：陈明和李宏钊王长瑞王宁李治佑唐丽娜南京航空航天大学直升机传动技术国家重点实验室江苏南京210016 上海航天设备制造总厂有限公司上海200245

金刚石/铜复合材料具有密度低、热导率高及热膨胀系数可调等优点,且与新一代芯片具有良好的热匹配性能,在高热流密度电子封装领域具有非常广泛的应用前景。然而由于金刚石与铜界面润湿性差,界面热阻高,导致材料热导率比铜还低,限制了其... 详细信息

金刚石/铜复合材料具有密度低、热导率高及热膨胀系数可调等优点,且与新一代芯片具有良好的热匹配性能,在高热流密度电子封装领域具有非常广泛的应用前景。然而由于金刚石与铜界面润湿性差,界面热阻高,导致材料热导率比铜还低,限制了其应用。为了改善其界面润湿性,通过在金刚石表面金属化或对铜基体预合金化等手段来修饰复合材料界面,以提高金刚石/铜复合材料的热导率。本文综述了表面改性、导热模型相关的界面理论以及有限元模拟的研究进展,讨论了制备工艺、导热模型和未来发展的关键方向,总结了金刚石添加量、颗粒尺寸等制备参数对其微观组织结构和导热性能的影响规律。

关键词：金刚石/铜复合材料界面润湿性界面理论有限元仿真

基于分数阶微分和最优光谱指数的大豆叶面积指数估算

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农业机械学报 2023年第9期54卷 329-342页

作者：向友珍王辛安嘉琪唐子竣李汪洋史鸿棹西北农林科技大学旱区农业水土工程教育部重点实验室陕西杨凌712100 西北农林科技大学水利与建筑工程学院陕西杨凌712100

高光谱遥感技术可对作物生长状况进行无损、高效地监测,是推动现代精准农业发展的必要手段。以不同施氮水平与覆膜处理下的开花期大豆叶面积指数(Leaf area index, LAI)为研究对象,对原始开花期大豆高光谱反射率数据进行0~2阶微分变换处... 详细信息

高光谱遥感技术可对作物生长状况进行无损、高效地监测,是推动现代精准农业发展的必要手段。以不同施氮水平与覆膜处理下的开花期大豆叶面积指数(Leaf area index, LAI)为研究对象,对原始开花期大豆高光谱反射率数据进行0~2阶微分变换处理(步长0.5),并筛选出各阶光谱指数中与开花期大豆LAI相关性最高的指数作为最优光谱指数进行输入,采用支持向量机(Support vector machine, SVM)、随机森林(Random forest, RF)、遗传算法优化的BP神经网络(BP neural network optimized by genetic algorithm, GA-BP)3种机器学习方法构建大豆LAI预测模型。结果表明:0~2阶光谱指数与大豆LAI相关系数平均值分别为0.616、0.657、0.666、0.669、0.658,相比于原始与整数阶高光谱反射率,分数阶微分变换处理后的高光谱反射率构建的光谱指数与开花期大豆LAI具有更强的相关性;相关系数平均值最高的1.5阶微分处理最优光谱指数波长组合分别为:TVI(687 nm, 754 nm)、DI(687 nm, 754 nm)、SAVI(728 nm, 738 nm)、RI(687 nm, 744 nm)、NDVI(620 nm, 653 nm),其余各阶最优光谱指数组合对应波段也集中分布于红边波段(680~760 nm);随着微分阶数提高,光谱指数与大豆LAI的相关性和构建的预测模型的精度均呈先升后降的趋势;当输入变量相同时,RF为3种机器学习模型中的最佳建模方法。经过综合比较,以1.5阶微分处理得到的最优光谱指数组合作为输入数据,基于RF构建的大豆LAI预测模型取得了最高的精度,验证集的决定系数R~2为0.880,均方根误差(RMSE)为0.320 0 cm~2/cm~2,标准均方根误差(NRMSE)为10.354%,平均相对误差(MRE)为9.572%。研究结果可为提高大豆LAI高光谱反演精度与指导精准农业生产提供理论参考。

关键词：大豆叶面积指数高光谱分数阶微分最优光谱指数