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191.
Land surface temperature is a key parameter in monitoring the status of crop water stress by remote sensing, and studying the water and energy balance in cropland ecosystem. The component temperatures of crop and soil are especially significant in remote …  相似文献   
192.
To develop geosciences quantification and multi-dimensional researches will be an inevitable trend in the 21st century. The interaction between the land surface and the atmosphere not only serves as an important component in geosciences quantification, bu…  相似文献   
193.
Matrix expression of thermal radiative characteristics for an open complex   总被引:6,自引:0,他引:6  
The directionality of thermal radiance of a homogeneous isothermal non-black plane surface is totally decided by its directional emissivity, which depends on the complex dielectric constant and roughness of surface. It can be expressed by This paper proves that it is necessary to express emissivity by a matrix when a target becomes an inhomogeneous non-isothermal open complex with complicated inner geometric structure. The matrix describes the inner radiative interaction among components accurately and also expresses its thermal radiative directionality and structural characteristics completely. Advantages of matrix expression are as follows: first, the physical mechanics of effective emissivity of an open complex is described in a simple and perfect way; second, it becomes easy to understand the principle and method to retrieve components temperature from multi-angle thermal remotely sensed data; and third, the differences of directionalities between an open complex and a homogeneous isothermal non-black plane body are expressed by just using an effective emissivity matrix instead of an emissivity vector. Formula in classic physics is only the special case of matrix expression; therefore, the matrix is a universal unconditional expression to describe the directionality of thermal radiance.  相似文献   
194.
Granites sampled from Garzê-Litang thrust, Longmen Shan thrust, Garzê and Litang strike-slip faults in the eastern Tibetan Plateau have been analyzed with apatite fission track thermochronological method in this study. The measured fission track apparent ages, combined with the simulated annealing mod- eling of the thermal history, have been used to reconstruct the thermal evolutionary histories of the samples and interpret the active history of the thrusts and faults in these areas. Thermal history mod- eling shows that earlier tectonic cooling occurred in the Garzê-Litang thrust in Miocene (~20―16 Ma) whereas the later cooling occurred mainly in the Longmen Shan thrust since ~5 Ma. Our study sug- gests that the margin of eastern Tibetan Plateau was extended by stages: through strike-slip faults deformations and related thrusts, the upper crust formed the Garzê-Litang margin in the Miocene epoch and then moved to the Longmen Shan margin since ~5 Ma. During this process, the deformations of different phases in the eastern Tibetan Plateau were absorbed by the thrusts within them and conse- quently the tectonic events of long-distance slip and extrusion up to hundreds of kilometers have not been found.  相似文献   
195.
地震活动热红外异常的影响因素分析   总被引:5,自引:0,他引:5  
屈春燕  单新建  马瑾 《地震研究》2007,30(2):113-119
对地表热红外辐射的基础理论和各类地物的热红外辐射特性进行了简略介绍;对地形地貌、地物类型和气象等非震因素对地表热红外辐射的影响及地表热红外亮温的时空变化特征进行了详细的分析;对各类非震因素的去除方法进行了探讨。初步认为,充分研究活动构造区带在各类非震因素影响下的热红外影像特征,掌握无震条件下的红外亮温时空演化过程,建立红外亮温变化的基准模型及各类非震因素的扣除模型,将有可能较好地排除非震因素的影响,检测出与地震活动有关的热异常。  相似文献   
196.
Our analysis of the continuous outgoing long wave earth radiation (OLR) indicates anomalous variations prior to a number of medium to large earthquakes. The most recent analysis of OLR is from the M9.0 Sumatra Andaman Islands mega trust event. We compared the reference fields for December 2001 to 2004 and found OLR anomalous values, > 80 W/m2, (2σ) within the epicentral area on Dec 21, 2004, 5 days before the event. We used the NOAA/IR daily (one degree) and monthly (two and half degree) gridded data to differentiate between the global and seasonal variability and the transient local anomalies. The cause of such anomalies is not fully understood; one possible explanation is the existence of thermal outgoing radiation as a result of near ground air ionization and latent heat change due to change of air humidity and temperature. This phenomenon is hypothesized to be part of a relationship between tectonic stresses, electrochemical and thermodynamic processes in the atmosphere and increasing mid IR flux, all part of a family of electromagnetic (EM) phenomena related to earthquake activity. The time scale of the observed variations is a few weeks before the onset of the seismic event. In comparison with several years of data, the observed time-series preceding the earthquake had unusually high OLR. The OLR anomaly corresponds to a large area of ground coverage and coincides with the main epicentral zone. The significance of these observations is explored using data from most recent East Asian earthquake swarm of December 2004 and three other earthquakes.  相似文献   
197.
应用1994—2003年NCEP逐日再分析资料,对石河子地区10a夏季出现的10次持续性高温天气过程进行了综合分析,总结了石河子地区高温天气的主要环流及相关物理量的特征,提出了石河子地区夏季高温天气的预报模型。  相似文献   
198.
CTP(计算机直接制版)技术,特别是热敏直接制版技术已经在世界范围内得到了广泛应用,它是印刷工业发展的大趋势。在某种程度上说,CTP技术推动了数码打样技术的发展,数码打样设备成了CTP系统必需配备的关键设备。针对CTP技术和数码打技术以及二者的关系进行了介绍与讨论,进一步对数码打样技术的应用进行了理论上和实践上的探讨。另外,在CTP环境下,比较细致地分析和讨论了如何输出数码打样来模拟胶印效果,通过多次数码打样实验、数据分析与校正,最终数码打样与胶印结果非常接近。  相似文献   
199.
焦作市的农业气候资源丰富,雨热同季,并有不完全同步的特性,10℃以上活动积温为4653~4960℃.d,降水量为548.8~590.5 mm,主要分布在4-10月,日照时数2107.5~2444.9 h。近40 a热量资源呈增多趋势,20世纪90年代的热量资源明显多于前30 a,水分变化不明显,日照时数呈递减趋势。  相似文献   
200.
热解硫酸钡制备硫同位素分析试样二氧化硫   总被引:1,自引:1,他引:0  
改进了硫同位素分析中由BaSO4制备SO2的方法:BaSO4和V2O5及SiO2混合后覆盖铜丝,在真空状态980℃加热20min,用液氮捕集SO2。与火焰直接加热分解法相比,用高温炉方便,改善了制样环境,避免污染。经国际标样和国家标准物质分析验证,结果与标准值相符,标准偏差(1σ)在±009‰~±020‰,符合分析要求。  相似文献   
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