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991.
Using the tropical cyclone (TC) data derived from the Joint Typhoon Warning Center (JTWC) and the sea surface temperature data derived from the Joint Environmental Data Analysis Center (JEDAC) at the Scripps Institute of Oceanography from January 1955 to December 2000, we analyzed the relationship between the TC genesis over the Northwest Pacific (NWP) and the sea surface temperature anomalies (SSTA) over the Pacific basin. A long-term trend indicated that the highest frequency of monthly TC genesis appeared earlier and the annual genesis sum increased gradually during the last half century with some oscillations. No significant synchronous correlation was found between the NWP TC events and the SSTA over the Pacific basin, while the annual sum of TC genesis was closely related with the SSTA averaged from the first three months (January, February and March) of the year in the equatorial western and eastern Pacific and over mid-high latitudes of the North Pacific. The results implied that there are an interannual El Nio SSTA mode in the equatorial western and eastern Pacific and an interdecadal SSTA mode in the northern Pacific, which affected the TC genesis. A regression analysis between the first three-month SSTA and the annual TC sum based on two time scales was conducted. The correlation coefficient between simulated and observed TC sums reached a high value of 0.77. 相似文献
992.
相似模拟实验中光纤光栅传感测试的温度补偿 总被引:1,自引:0,他引:1
为了提高光纤光栅的测试水平,研究了相似模拟实验中光纤光栅传感测试的温度补偿方法。采用了不受力温度补偿法。将温度补偿光栅埋设于模型外的相似材料模块中。模型开采过程中模块仅感受温度的变化,不受任何外力;模型内的测试光栅同时感受温度和应变的变化。实验表明,在外界温度变化的情况下,温度的影响作用明显,因此,剔除温度的影响很有必要。使用不受力法可以消除温度的影响,解决了相似模拟实验中光栅测试的交叉敏感问题,提高了测试的精度。 相似文献
993.
Using the tropical cyclone (TC) data derived from the Joint Typhoon Warning Center (JTWC) and the sea surface temperature data derived from the Joint Environmental Data Analysis Center (JEDAC) at the Scripps Institute of Oceanography from January 1955 to December 2000, we analyzed the relationship between the TC genesis over the Northwest Pacific (NWP) and the sea surface temperature anomalies (SSTA) over the Pacific basin. A long-term trend indicated that the highest frequency of monthly TC genesis appeared earlier and the annual genesis sum increased gradually during the last half century with some oscillations. No significant synchronous correlation was found between the NWP TC events and the SSTA over the Pacific basin, while the annual sum of TC genesis was closely related with the SSTA averaged from the first three months (January, February and March) of the year in the equatorial western and eastern Pacific and over mid-high latitudes of the North Pacific. The results implied that there are an interannual El Nio SSTA mode in the equatorial western and eastern Pacific and an interdecadal SSTA mode in the northern Pacific, which affected the TC genesis. A regression analysis between the first three-month SSTA and the annual TC sum based on two time scales was conducted. The correlation coefficient between simulated and observed TC sums reached a high value of 0.77. 相似文献
994.
Xie Aihong Qin Dahe Ren Jiawen Qin Xiang Xiao Cunde Hou Shugui Kang Shichang Yang Xingguo Jiang Youyan 《自然科学进展(英文版)》2007,17(7):828-837
Mount Everest,the highest point on the Earth is often referred to as the earth's third pole as such the place is relatively inaccessible and little is known about its meteorology.In April 2005,an automatic weather station was installed at the mountain's North Col(6523 m a.s.l.).According to the observational 10-minute mean and daily records,the meteorological characteristics were analyzed. All the meteorological elements displayed obvious diurnal variations during May 1 to July 22,2005.The monthly variation of daily meteo- rological elements on Mount Everest coincided with that on Dingri,the closest routine meteorological station,with the high correlation co- efficients of 0.928,0.877,0.682,0.755,0.826 and 0.676(n=83,p<0.001)for mean temperature,minimum temperature,max- imum temperature,relative humidity,pressure and wind speed,respectively.Furthermore,the vertical mean gradient of temperature was above 0.6℃/100 m,especially for the daily maximum temperature.Most weather events on Mount Everest prominently appeared on the same day as those on Dingri,especially those from daily mean pressure,temperature and relative humidity with the cross-correlation coeffi- cients of 0.673,0.485 and 0.487(n=83,p<0.001),respectively.Some other weather events on Mount Everest lagged one-day be- hind those on Dingri.Furthermore,forecasting of the weather events on Mount Everest from pressure on Dingri was more reliable than those from the other meteorological elements.The conclusions are much important for research on meteorology and climate changes in the region. 相似文献
995.
Daily variation of carbon flux in soils of Populus euphratica forests in the middle and lower reaches of the Tarim River 总被引:1,自引:0,他引:1
In order to lucubrate the daily variation of respiration in soils of Populus euphratica forests and analyze its relationship with environmental factors in the middle and lower reaches of the Tarim River, the LI-8100 instrument of soil CO2 flux system was used to measure the parameters of soil carbon flux and air temperature 10 cm above ground surface along the profiles of Usyman, Archy River, Yengisu and Karday, and the relationships between the soil carbon flux and the soil moisture content were analyzed. The nonlinear regression analysis was carried out with the software SPSS13.0. We observed that: (1) soil respiration began to be restrained when the air temperature was up to 30℃10 cm above the ground surface; (2) the rates of soil respiration under the forests of Populus euphratica were significantly different at various moisture contents, the soil carbon flux was high along the Usyman profile, which has a high soil moisture content, and it was low along the profiles of Archy River, Yengisu and Karday, which has a low soil moisture content; (3) the exponential model can be used to explain the relationship between soil respiration and air temperature 10 cm above the ground surface. The average Q10 values along the profiles of Usyman, Archy River, Yengisu and Karday are 0. 61, 0.16, 0. 22 and 0. 35 respectively, much lower than the average of the world; (4) there is a positive correlation between the soil carbon flux and the soil moisture content. 相似文献
996.
应用耐冷菌株改善寒冷地区冬季人工湿地系统生物脱氮效果 总被引:6,自引:0,他引:6
通过探索性实验,确定了三种耐冷菌培养基,分别用于培养耐冷细菌、耐冷放线菌和耐冷霉菌.培养出的耐冷菌株在6℃条件下被分离纯化,然后通过一系列实验分别鉴定它们的生理特性并检验它们的脱氮能力,并测定pH值、温度对脱氮效果的影响规律.实验结果显示pH值为7~8时,各菌株生长得最好;生物荧光层析光谱实验发现三种菌株都在15℃左右活性最大,0℃以下仍有一定的活性,高于35℃时,基本失去正常的代谢能力.当实验菌液投加量为5.0%,实验温度为6℃,三种耐冷菌对氨氮的去除率分别为57.7%、59.0%及58.7%,相同条件下,投加混合菌种可使氨氮的去除率提高到67.2%. 相似文献
997.
退火温度对25Mn-3Si-3Al-TWIP钢组织和力学性能的影响 总被引:2,自引:0,他引:2
研究了不同退火温度对25Mn-3Si-3Al-TWIP钢组织和力学性能的影响.结果表明经1000℃退火后,此钢种可达到640MPa左右的抗拉强度和255MPa左右的屈服强度以及82%以上的延伸率,具有较好的综合力学性能.其室温组织为单相奥氏体基体的退火孪晶,通过TEM观察内部为大量的层错和孪晶共存结构.在随后的拉伸变形过程中产生大量形变孪晶,发生了TWIP效应——孪晶诱发塑性效应,使钢板具有优良的力学性能. 相似文献
998.
对目前带钢横向温度分布的研究方法和结论进行了分析;对1800热连轧机精轧出口带钢的横向温度进行测量,针对典型的分布规律,提出了描述参数,并用该参数就其分布规律以及分布与带钢宽度、纵向温度的关系进行了讨论,为建立热连轧带钢横向温度控制模型提供了依据. 相似文献
999.
通过在马弗炉内以及循环流化床内对单元垃圾(土豆块)进行干燥试验,分别获得了其在炉内的干燥特性曲线.试验结果显示,在马弗炉内低温区干燥温度对垃圾干燥过程的影响较大;在同一干燥温度下,随着垃圾厚度的增加,干燥时间近似呈指数形式增加;在干燥的大部分阶段,土豆块内温度随含湿量减少呈逐渐上升趋势.在循环流化床内,土豆块的整个干燥过程中只有降速段,而不存在恒速段和初始段,垃圾厚度对干燥过程有显著影响. 相似文献
1000.
通过对2006年7月汉中市出现的持续高温天气进行分析,揭示持续高温天气发生发展的天气学原因,为今后的预报提供指导依据。同历史资料做对比,深入分析高温阶段天气形势特征。发现2006年汉中持续高温刷新了多项历史纪录:日最低气温28.1℃、日平均气温>30℃连续9天、日最低气温>25℃连续9天、日平均气温32.7℃。高温持续时间的长短,取决于副高的控制时间的长短,而副高控制时间的长短又与副高的位置、波长的长短有关。高空南亚高压的位置及持续时间也是高温天气得以持续的重要条件。台风及其减弱为弱低压后,其携带的大量暖湿水汽以及弱低压外围的偏北下沉气流对高温天气起到辅助加强作用。 相似文献