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1.
郭亚娜 《农技服务》2011,28(3):371-372
热带气旋会带来严重的财产和人员伤亡,是自然灾害之一。因为海洋上可能同时出现多个热带气旋,为了减少混乱,当热带气旋达到热带风暴的强度时,气象机构便会对其作出命名。热带气旋会根据各个区域不同的命名表命名,这些命名表是由世界气象组织的委员或各区负责预测热带气旋的机构制订。当前被命名的对生命或财产造成重大伤亡和损失的热带气旋,国际气象组织会讨论决定是否将其从循环名单中删除,再由原来这个名称的国家重新提交新的名称,而提供名字的地区亦可自行要求更换名字。新的名字必须获国际气象组织台风委员会全体通过。全面介绍2000~2009年10年间产生在南海及西北太平洋的热带气旋命名规则以及被除名的热带气旋。  相似文献   

2.
利用中国气象局整编的《热带气旋年鉴》资料以及NCEP/NCAR再分析资料,对比分析了2005年"达维"台风登陆海南岛过程与登陆越南大陆过程大尺度物理量场的垂直结构变化特征。结果表明,"达维"经过岛屿过程的结构演变与登陆大陆不同之处在于结构复原现象。登陆海南岛过程及岛上移动初期,水平风场的对称结构以及次级环流被破坏,在岛上移动后期及离岛入海过程,结构复原。"达维"台风经过海南岛过程水汽不被切断,反而由于陆地摩擦加大、辐合增强而导致水汽通量辐合增加,暖心及位涡中心下移,中低层对流在登陆岛屿过程短暂减弱后,在岛上移动阶段逐步加强。  相似文献   

3.
A substantial amount of frictional dissipation in the atmosphere occurs in the microphysical shear zones surrounding falling precipitation. The dissipation rate is computed here from recently available satellite retrieval from the Tropical Rainfall Measurement Missions and is found to average 1.8 watts per square meter between 30°S and 30°N. The geographical distribution of the precipitation-induced dissipation is closely tied to that of precipitation but also reveals a stronger dissipation rate for continental convection than for maritime convection. Because the precipitation-induced dissipation is of the same magnitude as the turbulent dissipation of the kinetic energy in the atmosphere, changes in the hydrological cycle could potentially have a direct impact on the amount of kinetic energy generated and dissipated by the atmospheric circulation.  相似文献   

4.
Phonon density of states of iron up to 153 gigapascals   总被引:4,自引:0,他引:4  
We report phonon densities of states (DOS) of iron measured by nuclear resonant inelastic x-ray scattering to 153 gigapascals and calculated from ab initio theory. Qualitatively, they are in agreement, but the theory predicts density at higher energies. From the DOS, we derive elastic and thermodynamic parameters of iron, including shear modulus, compressional and shear velocities, heat capacity, entropy, kinetic energy, zero-point energy, and Debye temperature. In comparison to the compressional and shear velocities from the preliminary reference Earth model (PREM) seismic model, our results suggest that Earth's inner core has a mean atomic number equal to or higher than pure iron, which is consistent with an iron-nickel alloy.  相似文献   

5.
在不同惯性系中对功和能量进行计算时,由于动能的计算在坐标变换中出现了交叉项,使它们的物理意义产生了混乱。本文通过对碰撞问题的分析,指出动能和势能一样,属于相互作用的整个物体系统,在一个真实的物理过程中,必须选择质心坐标系,才能正确地计算出各物体的动能和动能变化。  相似文献   

6.
贡嘎山暗针叶林林冠对降雨能量再分配的影响研究   总被引:8,自引:1,他引:7  
雨滴速度、雨滴动能等参量都与土壤侵蚀关系密切。充分考虑林冠结构特征与降雨特性,观测了贡嘎山不同演替阶段暗针叶林群落的林内降雨,采用经验公式和雨谱法计算出降雨雨滴的动能和势能。结果表明:雨滴终点速度与雨滴直径和雨滴动能的大小均成正比;在小雨强时,林冠可以增加降雨落地时的动能,有时甚至可以达到林外的2倍以上;林冠对降雨势能的消减量与降雨量和林冠截留量有显著相关关系,不同月份的降雨特征不同、林冠截留特征不同,致使林冠对降雨势能的削减能力也不同。  相似文献   

7.
运用聚类分析法进行中国农村家庭能源消费的区域划分   总被引:5,自引:0,他引:5  
选择人均有效热、人均电力、有效热中商品能比例、人均标煤、人均商品能、人均收入和年均气温作为中国农村家庭能源消费区域划分的特征指标,运用聚类分析法,根据各省、市农村家庭能源消费特征指标值相似程度,将其划分为5类不同区域,并分析各区域的主要特点,为省级农村能源规划和区域差异研究提供了依据。  相似文献   

8.
Thermoregulation in endothermic insects   总被引:2,自引:0,他引:2  
On the basis of body weight, most flying insects have higher rates of metabolism, and hence heat production, than other animals. However, rapid rates of cooling because of small body size in most cases precludes appreciable endothermy. The body temperature of small flies in flight is probably close to ambient temperature, and that of flying butterflies and locusts is 5 degrees to 10 degrees C above ambient temperature. Many moths and bumblebees are insulated with scales and hair, and their metabolism during flight can cause the temperature of the flight muscles to increase 20 degrees to 30 degrees C above ambient temperature. Curiously, those insects which (because of size, insulation) retain the most heat in the thorax during flight, also require the highest muscle temperature in order to maintain sufficient power output to continue flight. The minimum muscle temperature for flight varies widely between different species, while the maximum temperature varies over the relatively narrow range of 40 degrees to 45 degrees C. As a consequence, those insects that necessarily generate high muscle temperatures during flight must maintain their thoracic temperature within a relatively narrow range during flight. Active heat loss from the thorax to the abdomen prevents overheating of the flight motor and allows some large moths to be active over a wide range of ambient temperatures. Bumblebees similarly transfer heat from the flight musculature into the abdomen while incubating their brood by abdominal contact. Many of the larger insects would remain grounded if they did not actively increase the temperature of their flight muscles prior to flight. Male tettigoniid grasshoppers elevate their thoracic temperature prior to singing. In addition, some of the social Hymenoptera activate the "flight" muscles specifically to produce heat not only prior to flight but also during nest temperature regulation. During this "shivering" the "flight" muscles are often activated in patterns different from those during flight. The muscles contract primarily against each other rather than on the wings. However, the rate of heat production during shivering and flight is primarily a function of the action potential frequency rather than of the patterns of activation. Thermoregulation is a key factor in the energetics of foraging of some of the flower-visiting insects. The higher their muscle temperature the more flowers they can visit per unit time. When food supplies are ample, bees may invest relatively large amounts of energy for thermoregulation. While shivering to maintain high body temperatures during the short intervals they are perched on flowers (as well as while in the nest), bumblebees often expend energy at rates similar to the rates of energy expenditure in flight. Unlike vertebrates, which usually regulate their body temperature at specific set points, the body temperature of insects is labile. It often appears to be maintained near the lower temperature at which the muscles are able to perform the function at hand. The insects' thermal adaptations may not differ as much from those of vertebrates as previously supposed when size, anatomy, and energy requirements are taken into account.  相似文献   

9.
Bell LE 《Science (New York, N.Y.)》2008,321(5895):1457-1461
Thermoelectric materials are solid-state energy converters whose combination of thermal, electrical, and semiconducting properties allows them to be used to convert waste heat into electricity or electrical power directly into cooling and heating. These materials can be competitive with fluid-based systems, such as two-phase air-conditioning compressors or heat pumps, or used in smaller-scale applications such as in automobile seats, night-vision systems, and electrical-enclosure cooling. More widespread use of thermoelectrics requires not only improving the intrinsic energy-conversion efficiency of the materials but also implementing recent advancements in system architecture. These principles are illustrated with several proven and potential applications of thermoelectrics.  相似文献   

10.
Singer SF 《Science (New York, N.Y.)》1970,170(3963):1196-1198
Venus now has a retrograde and negligible spin, but it very likely started with a typical planetary spin: prograde and with a 10- to 20-hour period. The usually assumed mechanism of solar tidal friction is quite insufficient to remove this angular momentum. Instead, we postulate capture of a moonlike object from an initially retrograde orbit: it would despin Venus and suddenly transform the planet's rotational kinetic energy into internal heat, which would lead to volcanism and the liberation of large amounts of volatiles. The moon would disappear by crashing into the surface of Venus.  相似文献   

11.
介绍《热带作物学报》的基本情况,概述精品期刊的基本特征和遴选指标,提出《热带作物学报》精品之路的工作构想。  相似文献   

12.
Alfvén waves, transverse incompressible magnetic oscillations, have been proposed as a possible mechanism to heat the Sun's corona to millions of degrees by transporting convective energy from the photosphere into the diffuse corona. We report the detection of Alfvén waves in intensity, line-of-sight velocity, and linear polarization images of the solar corona taken using the FeXIII 1074.7-nanometer coronal emission line with the Coronal Multi-Channel Polarimeter (CoMP) instrument at the National Solar Observatory, New Mexico. Ubiquitous upward propagating waves were seen, with phase speeds of 1 to 4 megameters per second and trajectories consistent with the direction of the magnetic field inferred from the linear polarization measurements. An estimate of the energy carried by the waves that we spatially resolved indicates that they are too weak to heat the solar corona; however, unresolved Alfvén waves may carry sufficient energy.  相似文献   

13.
本文围绕2023年7月登陆我国华南沿海的2304号“泰利”热带气旋,利用CMA-STI热带气旋最佳路径数据集、NCEP/NCAR再分析I资料、NOAA每日(非插值)OLR资料,对登陆台风“泰利”在广西地区的暴雨增幅进行了特征分析。结果表明,登陆后的“泰利”被副热带高压、大陆高压、切断低压及副高延伸的高压脊包围,这样的环流形势有利于环流维持;“泰利”活动期间越赤道气流明显增强,索马里急流和80-90°E的越赤道气流在南海北部海域交汇后,将大量的水汽、动量和潜热能量注入登陆“泰利”环流,使其登陆后仍能维持一段时间;2023年7月第4侯,西南季风处于活跃期,触发低纬西南季风涌北传并侵入“泰利”环流,进而在广西地区产生暴雨增幅。此外,低层热力条件特征也是导致“泰利”暴雨增幅的重要原因。  相似文献   

14.
为深入认识热带气旋对嵊泗马鞍列岛贻贝养殖设施的影响,并为嵊泗贻贝养殖区位合理分布等提供基础资料,利用2000—2018年间的西北太平洋热带气旋资料、贻贝养殖面积和产量数据、环境要素的海洋实测数据和遥感数据、贻贝养殖区遥感影像数据,分析了热带气旋对嵊泗贻贝养殖海洋环境场、养殖区位及面积的变化影响,结合研究海域历史热带气旋移动路径和风场统计特征、马鞍列岛贻贝养殖区位多年变化结果、马鞍列岛底质类型和岛屿地理分布特点,提出了马鞍列岛贻贝养殖区位选择的建议。结果表明:2000—2018年间共有38个热带气旋进入影响海域范围,年均热带气旋数约有2个,热带气旋活动主要集中在7—9月,8月累积数量最多。热带气旋移动路径可分2个类型,类型Ⅰ热带气旋9个,以强台风级强度为主;类型Ⅱ热带气旋29个,分为两组,分别以热带风暴和台风级强度为主。海域全年的南东南—东东南向大风稀少,8月期间受热带气旋活动常出现9~11级西西北—北东北向大风。在“梅花”造成的东北向大风和急流海况下,2011年嵊泗贻贝养殖区出现大面积变形损毁。自2011年后,嵊泗贻贝养殖区面积经历了3次恢复与扩增,主养殖区趋于饱和,可在花鸟岛、东库山岛、求子山岛、柱住山岛和三横山岛弧岛链西面海域处尝试开辟新的贻贝养殖区。  相似文献   

15.
利用1949~2011年CMA-STI热带气旋(TC)最佳路径数据集,分析了西北太平洋各个等级热带气旋累积气旋能量(ACE)的时空分布特征。结果表明,各等级热带气旋ACE的年际时间序列中,热带风暴(TS)一直呈现缓慢发展趋势,其他等级则经历数个峰值,但其趋势不同;各等级热带气旋的平均ACE的年际时间序列中,热带风暴和台风(TY)呈现先减小、再增加、又减小的趋势,强热带风暴(STS)则呈缓慢增长的趋势,强台风(STY)则呈现10年左右的周期变化,而超强台风(SuperTY)则主要呈下降趋势。各月ACE分布中,TS、STS、TY、STY 4个等级的热带气旋均在9月达最大值,SuperTY在9月达最大值。TS、STS、TY的ACE空间分布的高频中心位于南海,STY和SuperTY的高频中心位于125°~135°E、15°~25°N的区域。  相似文献   

16.
根据对北京地区木本植物属的统计分析,结果可划分为14种土理分布类型,以温带分布为主,占区系成分属数的71.7%,其中以北温带分布类型占主导地位;与热带植物区系有一定联系,占区系成分的24.5%;与各大洲植物区系存在着广泛的联系。  相似文献   

17.
Interfacial charge-transfer rate constants have been measured for n-type Si electrodes in contact with a series of viologen-based redox couples in methanol through analyses of the behavior of these junctions with respect to their current density versus potential and differential capacitance versus potential properties. The data allow evaluation of the maximum rate constant (and therefore the electronic coupling) for majority carriers in the solid as well as of the dependence of the rate constant on the driving force for transfer of delocalized electrons from the n-Si semiconducting electrode into the localized molecular redox species in the solution phase. The data are in good agreement with existing models of this interfacial electron transfer process and provide insight into the fundamental kinetic events underlying the use of semiconducting photoelectrodes in applications such as solar energy conversion.  相似文献   

18.
The abnormally large values of the energy and the entropy of activation encountered in protein denaturations and enzyme destructions are illusory, since the customary method of calculating these quantities by the comparison of rates at constant p(H) alone is fallacious. This procedure includes, in addition to the true energy of activation, the heat of dissociation of all acidic equilibria involved in preparing the initial molecules for the kinetic step of activation. Steinhardt has shown by a simple and concrete mechanism that the kinetics of pepsin destruction obey the simple laws of chemical kinetics when correction is made for the preliminary acidic dissociation equilibria which are not part of the activation process.  相似文献   

19.
本文利用NCEP 再分析资料、台站观测资料、多普勒雷达资料等对2018 年3 月14~15 日出现 在吉林省的暴雪天气过程进行分析。结果表明:在暴雪天气出现之前,平直的纬向环流有能量集聚, 再加上后期环流的调整和有效位能转换为动能,且释放了大量能量,充足的动力和能量条件,有利于 暴雪天气的出现;这次的暴雪天气大的气候背景是冬季气温较高,且暴雪天气出现前一天的地面温度 较高,说明暴雪天气出现前的有能量储备较为充足;在降雪天气出现之前的触发机制是偏东急流,在 提供水汽的同时,还提供了触发条件;再加上偏北气流低  相似文献   

20.
中国马钱科植物的地理分布   总被引:2,自引:0,他引:2  
通过对中国马钱科植物地理分布的研究,把中国马钱科8属划分为5个分布区类型:1.泛热带分布:马钱属、度量草属、醉鱼草属;2.热带亚洲和热带美洲间断分布:钩吻属:3.旧世界热带(热带亚洲、非洲和大洋洲间断)分布:髯管花属;4.热带亚洲至热带大洋洲分布:灰莉属、尖帽草属;5.东亚(东喜马拉雅-日本)分布:蓬莱葛属。云南是我国马钱科植物的分布中心,拥有的属、种数分别是全国属、种数的87.5%和77.8%。  相似文献   

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