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981.
新一轮区调填图所获资料表明,加里东期花岗岩成因类型复杂多样,有岛弧花岗岩、同碰撞花岗岩及少量陆内造山花岗岩等,说明东昆仑东段在加里东时期经历了复杂的洋—陆俯冲、陆陆碰撞的动力学过程。  相似文献   
982.
针对无人值守大规模自动气象站的数据采集特点和要求,基于无线通信网络,设计了一种浪涌气象数据采集系统,并对其关键技术进行了深入讨论.首先,分析了系统数据传输的协议结构及存在的问题,设计了基于UDP协议的可靠应用协议,并就其工作过程及可靠性传输进行了详细的讨论,解决了无线数据传输的不稳定性问题;然后,利用多线程技术和大规模通信事件响应处理技术,提出了实现数据接收线程池的方法,通过引入"数据分区管理"的概念,论述了数据并发处理缓冲区的设计,解决了大并发系统容易丢失数据、堵塞和低效率等问题;最后,通过对系统测试及其在业务中应用的分析,表明该系统实时、高效、可靠,能满足目前业务的需求,并对未来业务的发展具有同样的适应性.  相似文献   
983.
Global warming is one of the greatest environmental, economic, and social threats in the world. There are many assessments to estimate climate variability over many regions. A change in the Earth’s surface temperature leads to increase in extreme temperature events, which are harmful to the ecosystem, and moreover, they create danger on human health. In this study, we have selected the western part of Turkey as the study area, since climate change projections for Turkey point out that the highest temperature change can be expected on this region during summer, and the Turkish population is very dense here to be affected by extreme events. We have used apparent temperatures to define the heat waves which we have determined their frequencies for the summer months (June–August) of 1965–2006. Since the regional comparisons of station results are intended, we selected the 90th percentile value for each station as a threshold value to be used in the delineation of heat waves. Then, the number of heat waves is determined by imposing the constraint that apparent temperatures stay above the threshold value at least for three consecutive days. Then, the changes in the number of hot days and heat waves and also their durations are analyzed by using the linear least square method. We have found that the number of hot days, heat waves, and heat wave durations is increased between 1965 and 2006 on the western part of Turkey. Additionally, their rate of change is larger within the last decade and extremes are frequently observed after 1998. Regional distributions show that the tendency of the number of heat wave events increases towards the southern latitudes of the domain. Moreover, we investigated the relationship between the number of hot days and the sea surface temperatures of the Mediterranean Sea and Black Sea. Correlation analyses are carried out by the number of hot days and averaged sea surface temperatures on the regions of the western, central, and eastern Mediterranean Sea and the Black Sea. It is found that the number of hot days of west Turkey is better correlated with the sea surface temperatures averaged over eastern Mediterranean and Black Seas. The number of heat waves is found significantly correlated with the fire occurrences for most of the stations.  相似文献   
984.
We present the first follow‐up study of the transiting system WASP‐41 after its discovery in 2011. The main goal of this paper is to refine the physical parameters of the system and search for possible signs of transit timing variations. The observations used for analysis were taken from the public archive of the Exoplanet Transit Database (ETD). Assuming three different limb darkening laws, we found the best‐fitting model and redetermined parameters of the system. Although system parameters obtained in this study were found to be in good agreement with the discovery study, the planetary radius determined here is notably smaller, namely 1.12+0.06 –0.07 RJup. The Safronov number Θ = 0.071 ± 0.002 and equilibrium temperature Teq = 1271 ± 50 K were also determined. Both values indicate that the planet WASP‐41b belongs to Class I of transiting planets. No significant transit timing variations were detected. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
985.
黄继国  杨柳  潘海楠  金坦 《世界地质》2011,30(1):128-131
利用蒸发法对中老龄垃圾渗滤液进行处理,通过定时分批对蒸发后的渗滤液进行取样测定,研究在不同蒸发温度、不同风速条件下渗滤液在蒸发过程中pH 值、有机物及氨氮含量的变化规律。结果表明: 蒸发浓缩液中pH 值变化幅度不大; 渗滤液中有机污染物在不同的蒸发条件下总量在减少,但减少量不大; 在蒸发温度为25℃,风速为1. 5 m/s 的条件下氨氮的去除效率为37%。  相似文献   
986.
在新近纪初期(约23 Ma)的时候,在当时中国大陆周边板块构造环境没有发生重大变化的情况下,华北克拉通东部构造活动性质仍发生了明显的变化.比如,华北克拉通东部的岩石圈增厚了,唐山-邢台断裂开始活动的同时太行山山前断裂却变得不活跃了,华北局部构造变形性质发生了变化等.虽然在古近纪和8 Ma以后,有证据显示印度-欧亚大陆的...  相似文献   
987.
浅层地温能是一种清洁,环保可再生的自然资源,通过热泵系统消耗少量电能即可用于建筑物供暖制冷,在节能减排中发挥着越来越重要的作用。针对目前地埋管换热系统单位延米抉热功率在设计中应用混乱的问题,本文从公式推导及现场试验数据分析出发,研究了国家标准《地源热泵系统工程技术规范》(GB50366--2005)和国土资源部行业标准《浅层地热能勘查评价规范》(DZ0225--2009)中关于现场热响应试验的方法及理论计算的关系,导出单孔的换热系数是单位热阻的倒数,它可以代表埋管的换热能力。提出其与直接测出单位廷米换热功率的区别,从而指导工程方案制定。  相似文献   
988.
提出一种基于异步比较法产生空满标志位,并利用锁存器实现标志位与时钟同步的FIFO,同时还给出了相应的Verilog HDL代码。该方法能提高时钟频率,节约版图面积。  相似文献   
989.
Heating and acceleration of electrons in solar impulsive hard X-ray (HXR) flares are studied according to the two-stage acceleration model developed by Zhang for solar 3He-rich events. It is shown that electrostatic H-cyclotron waves can be excited at a parallel phase velocity less than about the electron thermal velocity and thus can significantly heat the electrons (up to 40 MK) through Landau resonance. The preheated electrons with velocities above a threshold are further accelerated to high energies in the flare-acceleration process. The flare-produced electron spectrum is obtained and shown to be thermal at low energies and power law at high energies. In the non-thermal energy range, the spectrum can be double power law if the spectral power index is energy dependent or related. The electron energy spectrum obtained by this study agrees quantitatively with the result derived from the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) HXR observations in the flare of 2002 July 23. The total flux and energy flux of electrons accelerated in the solar flare also agree with the measurements.  相似文献   
990.
Traditionally, the mid-Holocene in most parts of China was thought to be warmer with higher precipitation, resulting from a strong Asian summer monsoon. However, some recent researches have proposed a mid-Holocene drought interval of millennial-scale in East Asian monsoon margin areas. Thus whether mid-Holocene was dry or humid remains an open issue. Here, Zhuyeze palaeolake, the terminal lake of the Shiyang River Drainage lying in Asian monsoon marginal areas, was selected for reconstructing the details of climate variations during the Holocene, especially mid-Holocene, on the basis of a sedimentological analysis. Qingtu Lake (QTL) section of 6.92m depth was taken from Zhuyeze palaeolake. Multi-proxy analysis of QTL section, including grain size, carbonate, TOC, C/N and δ13C of organic matter, was used to document regional climatic changes during 9-3 cal ka B.P. The record shows a major environmental change at 9.0-7.8 cal ka B.P., attributed to a climate trend towards warmth and humidity. This event was followed by a typical regional drought event which occurred during 7.8-7.5 cal ka B.P. And a warm and humid climate prevailed from 7.5 to 5.0 cal ka B.P., attributed to the warm/humid Holocene Optimum in this region. After that, the climate gradually became drier. Moreover, comparison of the climate record from this paper with the summer insolation at 30°N indicates that the climate pattern reflecting the Asian monsoon changes was caused by insolation change.  相似文献   
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