星载微波SSM/I对中国西北沙漠地区遥感数据的辐射特征分析   总被引：3，自引：3，他引：3  

金亚秋 《遥感学报》1997,1(3):192-197

该文研究了星载波ＳＳＭ／Ｉ对中国西北沙漠地区辐射亮度温度遥感数据的辐射特征，给出了西北沙漠某些地区ＳＳＭ／Ｉ各通道ＴＢ１９９５年全年的变化，１９９３年和１９９６年３７ＧＨｚ垂直和水平极化两通道ＴＢ的极化指数５月份全月平均值的空间分布及其差异值的比较。  相似文献   

大洋性次表层和中层水团隶属函数的拟合与应用     

李凤岐  李曜  谢骏 《中国海洋大学学报(自然科学版)》2003,33(6):833-840

本文针对大洋性水团的 T- S曲线族特征 ,提出了拟合其隶属函数的 2种方法——直线定位法和坐标旋转法。把这 2种方法应用于拟合巴士海峡两侧的次表层高盐水团和中层低盐水团的隶属函数并进行了讨论。文中给出了拟合的原理、公式和实例 ,表明它们在分析水团的分布特征、混合变性过程 ,特别是追踪其来源等方面是很有价值的  相似文献   

2002～2003渤海海冰数值预报   总被引：3，自引：5，他引：3  

刘钦政  刘煜  白珊  张启文  李宝辉  李春花 《海洋预报》2003,20(3):60-67

海冰数值预报是海冰业务预报的主要方法之一。国家海洋环境预报中心建立了业务化的渤海海冰数值预报系统，并进行了多年的业务化运行。随着我国卫星遥感事业和数值天气预报技术的发展，海冰预报系统也在不断发展中。本文介绍了2002～2003冬季应用HY—1卫星海冰遥感和T213数值天气预报模式产品对该海冰数值预报系统的改进，对2002～2003冬季海冰数值预报的结果进行了分析和比较。  相似文献   

草鱼外周血淋巴细胞体外转化诸因素的研究   总被引：8，自引：0，他引：8  

李亚南  陈全震  邵健忠  王冀平  毛树坚 《海洋与湖沼》1996,27(4):380-385

于１９９３年３月－１９９３年１１月，采自＾３Ｈ－ＴｄＲ同位素掺入法，分别测定草鱼外周血中淋巴细胞在经两种特异有丝分裂植物凝集素（ＰＨＡ）与金黄色葡萄球菌蛋白Ａ（ＳＰＡ）刺激后发生的Ｔ淋巴细胞与Ｂ淋巴细胞应答转化的平均刺激指数（ＳＩ）的值，经不同浓度的ＰＨＡ与ＳＰＡ刺激的Ｔ，Ｂ淋巴细胞转化实验表明，两种有丝分裂原促Ｔ，Ｂ淋巴细胞应答转化的最适剂量，ＰＨＡ为５００μｇ／ｍｌ，ＳＰＡ为０．０５％，用不同  相似文献   

A near infrared speckle imaging study of T Tauri Stars     

A. M. Ghez  D. W. Mccarthy Jr.  A. J. Weinberger  G. Neugebauer  K. Matthews 《Experimental Astronomy》1994,3(1-4):297-300

The results of a speckle imaging survey of T Tauri stars suggest that most, if not all, young low mass stars have companions. Repeated observations of these young binary stars have revealed orbital motion in the closest pairs (0.3), proving that these systems are indeed gravitationally bound and providing the basis for mass estimates in the upcoming years. These mass estimates are necessary to distinguish between the various binary star formation mechanisms that have been proposed to date.  相似文献   

Carbon and oxygen isotopes of Maastrichtian–Danian shallow marine carbonates: Yacoraite Formation, northwestern Argentina     

Rosa Marquillas  Ignacio Sabino  Alcides Nobrega Sial  Cecilia del Papa  Valderez Ferreira  Stephen Matthews 《Journal of South American Earth Sciences》2007,23(4):304-320

The Maastrichtian–Danian limestones of the Yacoraite Formation (northwestern Argentina) show carbon and oxygen isotopic values consistent with shallow marine conditions. The members of the formation respond to different sedimentary environments and are characterised by distinctive stable isotopes and geochemistry. The basal Amblayo Member is composed of high-energy dolomitic limestones and limestones with positive isotopic values (+2‰ δ¹³C, +2‰ δ¹⁸O). The top of the member reveals an isotopic shift of δ¹³C (−5‰) and δ¹⁸O (−10‰), probably related to a descent in the sea level. The sandy Güemes Member has isotopically negative (−2‰ δ¹³C, −1‰ δ¹⁸O) limestones, principally controlled by water mixing, decreased organic productivity, and compositional changes in the carbonates. The isotopically lighter limestones are calcitic, with a greater terrigenous contribution and different geochemical composition (high Si–Mn–Fe–Na, low Ca–Mg–Sr). These isotopic and lithological changes relate to the Cretaceous–Palaeogene transition. The Alemanía Member, composed of dolomitic limestones and pelites, represents a return to marine conditions and shows a gradual increase in isotopic values, reaching values similar to those of the Amblayo Member. The Juramento Member, composed of stromatolite limestones, shows isotopic variations that can be correlated with the two well-defined, shallowing-upward sequences of the member.  相似文献   

Trend analysis in Turkish precipitation data   总被引：9，自引：0，他引：9  

Turgay Partal  Ercan Kahya 《水文研究》2006,20(9):2011-2026

This study aims to determine trends in the long‐term annual mean and monthly total precipitation series using non‐parametric methods (i.e. the Mann–Kendall and Sen's T tests). The change per unit time in a time series having a linear trend was estimated by applying a simple non‐parametric procedure, namely Sen's estimator of slope. Serial correlation structure in the data was accounted for determining the significance level of the results of the Mann–Kendall test. The data network used in this study, which is assumed to reflect regional hydroclimatic conditions, consists of 96 precipitation stations across Turkey. Monthly totals and annual means of the monthly totals are formed for each individual station, spanning from 1929 to 1993. In this case, a total of 13 precipitation variables at each station are subjected to trend detection analysis. In addition, regional average precipitation series are established for the same analysis purpose. The application of a trend detection framework resulted in the identification of some significant trends, especially in January, February, and September precipitations and in the annual means. A noticeable decrease in the annual mean precipitation was observed mostly in western and southern Turkey, as well as along the coasts of the Black Sea. Regional average series also displayed trends similar to those for individual stations. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

华北地区降雹时空分布特征   总被引：15，自引：2，他引：15  

杨贵名  马学款  宗志平 《气象》2003,29(8):31-34

应用1991—2000年华北地区基本站资料，统计分析了华北地区降雹的时空分布特征。结果表明：(1)与阴山山脉以及太行山脉有关的主要降雹高频区，组成了“T”型分布特征；(2)从旬或候雹日演变看，冰雹年变化具有三峰型；(3)降雹日变化有季节性特点。  相似文献   

T213模式对强冷空气短期预报能力的分析检验   总被引：7，自引：1，他引：7  

张守峰  郭文华  张金艳  杨克明 《气象》2003,29(8):43-47

利用T213模式的500hPa高度、地面气压、850hPa温度预报格点资料和客观分析实况格点资料，对2001—2002年冬半年我国出现的8次强冷空气天气过程的主要影响天气系统进行了预报能力的客观分析检验。所得结果有利于数值预报产品的释用及实时预报业务。  相似文献   

2001年夏季风活动与我国南方暴雨某些特征的分析   总被引：5，自引：0，他引：5       下载免费PDF全文

马岚吴晓京  江吉喜张其松 李小龙 《应用气象学报》2003,14(4):445-451

应用GMS T_BB资料对2001年亚洲夏季风活动作了诊断分析，得到中南半岛和我国南海共经历了3次季风爆发过程，且强度都强于历史同期水平；揭示了印度—孟加拉湾、中南半岛以及我国南海3个季风区季风爆发与间歇的特征。分析了季风对华南及长江中下游地区三次（6月上旬至中旬初、6月下旬至7月上旬、8月末）暴雨过程的影响，指出季风爆发及其与北方南下冷空气的结合，是造成东南部地区出现大范围长时间强降水的必要条件，从而为该地区强降水过程预报提供某些重要线索。  相似文献