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991.
Accurate rainfall distribution is difficult to acquire based on limited meteorological stations, especially in remote areas like high mountains and deserts. The Hexi Corridor and its adjacent regions (including the Qilian Mountains and the Alxa Plateau) are typical districts where there are only 30 available rain gauges. Tropical Rainfall Measuring Mission (TRMM) data provide a possible solution. After precision analysis of monthly 0.25 degree resolution TRMM 3B43 data from 1998 to 2012, we find that the correlations between TRMM 3B43 estimates and rain gauge precipitation are significant overall and in each station around the Hexi Corridor; however, the biases of annual precipitation differ in different stations and are seriously overestimated in most of the sites. Thus, Inverse Distance Weighting (IDW) interpolation method was used to rectify TRMM data based on the difference between TRMM 3B43 estimates and rain gauge observations. The results show that rectified TRMM data present more details than rain gauges in remote areas where there are few stations, alt- hough they show high coherence of distribution. Precipitation decreases from southeast to northwest on an annual and seasonal scale. There are three rainfall centers (〉500 mm) including Menyuan, Qilian and Toson Lake, and two low rain- fall centers (〈50 mm) including Dunhuang and Ejin Banner. Meanwhile, precipitation in most of the study area presents an increasing trend; especially in northern Qilian Mountains (〉5 mm/a), Badain Jaran Desert (〉2 mm/a), Toson Lake (〉20 mm/a) and Qingtu Lake (〉20 ram/a) which shows a significant increasing trend, while precipitation in Hala Lake (〈-2 mm/a) and Tengger Desert (〈-3 mm/a) demonstrates a decreasing trend.  相似文献   
992.
海洋褐藻胶生产废水的絮凝-氧化处理研究   总被引:2,自引:0,他引:2  
使用新型高效的絮凝剂Xp,对海洋褐藻胶生产废水进行絮凝,催化氧化处理试验,确定了絮凝剂Xp的最佳使用条件,催化氧化时间和氧化剂用量,结果表明,经本工艺处理后,废水中主要污染物CODcr的去除率达到83.9%,处理后的废水基本达到国家《污水综合排放标准》(GB8978-1996)限定的二级标准。  相似文献   
993.
地震活动性的细胞自动机模型   总被引:8,自引:0,他引:8       下载免费PDF全文
本文在二维平面设计了一个模拟地震活动性的细胞自动机模型,分析了模拟地震离列的活动性,并探讨了强震前场兆和源兆的物理机制,结果表明,模型的地震序列很好地反映了实际地震的丛集特性、幂律关系和空间转移概率的稳定性等特点。  相似文献   
994.
由震源机制和地震波各向异性探讨青藏高原岩石圈变形   总被引:9,自引:1,他引:9  
吕庆田  许志琴 《地质论评》1997,43(4):337-346
本文据青藏高原天然地震震源参数和地震波各向异性资料,讨论了高原岩圈不同圈层的变形特性。  相似文献   
995.
晚石炭世—早二叠世在中亚南天山造山带形成了大量的花岗质侵入岩.中国境内这些岩体以晚石炭世Ⅰ型花岗岩、早二叠世Ⅰ型和S型花岗岩以及最晚期的A型花岗岩为代表.不同类型的岩石在源区特征和岩浆形成的温压条件上存在一定的差异,而这些差异性反映了该时期内构造环境的演化过程.本文选取铁列克岩体、盲起苏岩体、英买来岩体、川乌鲁杂岩体、...  相似文献   
996.
1INTRODUCTION Ecological shelter construction (ESC) in the upper reaches of the Changjiang (Yangtze) River has been an important component of Development Program of West- ern China. In recent years, most of the literatures dis- cussing the meanings and goals of ESC have been fo- cused on the macro-level, and the scholars have concep- tualized it as a comprehensive strategy to promote the sustainable development of regional economy, society and environment, in which forestry's construc…  相似文献   
997.
胶南造山带的重磁场特征为一条醒目的重力低、磁力高值带,走向北东-南西,陆上部分长约450km,宽40~70km。其重磁场值一般为0×10-5m/S2~20×10-5m/S2、0~300nT,反映胶南造山带的轮廓及带内低密度的早元古代晋宁期花岗岩基和中强磁性的中生代燕山晚期岩浆岩的分布。根据重力场降低、磁异常升高程度和规模大小(宽窄),该重磁场带又可分为日照-青岛、乳山-威海、即墨-海阳三段,前者重力低、磁力高的程度较强,范围较大。造山带内重磁异常值具负相关关系,域值呈正相关性,即重力值越低的地区磁异常值越高,二者的范围大体相当。这一特征反映了造山带内部早元古代晋宁期花岗片麻岩的发育程度和中生代岩浆岩侵入的规模。胶南造山带的重力低、磁力高值带与连云港-苏山岛重力高、磁力低值带恰成对照。后者重磁场值一般为10×10-5m/S2~30×10-5m/S2、一50~-100nT,反映连云港-苏山岛块体的结晶基底由高密度、低磁性的原东海群、荆山群包体和无古宙侵入岩组成。该造山带南东侧西低东高的重力梯度带(Vzz=1.2×10-5m·S-2/km~1.75×10-5m·S-2/km)反映了赣榆一荣成断裂(倾向NW)的存在;北西侧正磁异常带表明该断裂为控岩断裂,其南段的正负重力梯度带(Vzz=1.0×10-5m·S-  相似文献   
998.
The changes in heme (associated with hemoglobin), hemoglobin and hematin in the coelomic fluid of marine worm, Urechis unicinctus, exposed to different concentrations of sulfide, were investigated using biochemical techniques. When exposed to different sulfide concentrations for up to 96 h, the relative amounts of the three components changed in a regular pattern suggesting that the coelomocytes play an important role in the worm's tolerance to sulfide. The possible roles of heme compounds in sulfide tolerance of this species are discussed on the basis of our experimental data.  相似文献   
999.
Observations of AGNs and microquasars by ASCA, RXTE, Chandra and XMM-Newton indicate the existence of broad X-ray emission lines of ionized heavy elements in their spectra. Such spectral lines were discovered also in X-ray spectra of neutron stars and X-ray afterglows of GRBs. Recently, Zakharov et al. [MNRAS 342 (2003) 1325] described a procedure to estimate an upper limit of the magnetic fields in regions from which X-ray photons are emitted. The authors simulated typical profiles of the iron Kα line in the presence of magnetic field and compared them with observational data in the framework of the widely accepted accretion disk model. Here we further consider typical Zeeman splitting in the framework of a model of non-flat accretion flows, which is a generalization of previous consideration into non-equatorial plane motion of particles emitting X-ray photons. Using perspective facilities of space borne instruments (e.g., Constellation-X mission) a better resolution of the blue peak structure of iron Kα line will allow to evaluate the magnetic fields with higher accuracy.  相似文献   
1000.
1INTRODUCTION The level and periodic changes of land price are interest- ing subjects for the governors, investors, researchers and grass-roots. Currently, the higher land price in China has become the focus among the people, from central go- vernment tocommon citizens,especially in theChang- jiang (Yangtze) River Delta area around Shanghai City. So that studyingthisproblem have both an academic and practicalmeaning. One characteristic ofland is fixed location (the others are high cost…  相似文献   
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