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61.
62.
在HAc-NaAc形成的中性缓冲溶液体系中,利用碘的催化动力学原理,使N-N-四甲基-4-4-二氨基二苯甲烷与氯胺T的氧化反应,生成蓝色络合物来测定地探样中微量碘的含量。通过实验,最佳试剂加入量为8%的HAc溶液5mL,8%的Na2CO3溶液3mL,0.1%的N-N-四甲基-4-4-二氨基二苯甲烷溶液5mL所组成的溶液体系中,在加入0.1%的氯胺T1mL显色后,其测定结果准确度、精密度高,检出限低,测定化探样中微量碘时该方法可以推广应用。 相似文献
63.
“7.15”宜昌大暴雨的地形影响特征 总被引:2,自引:0,他引:2
湖北地形复杂,受地形影响产生的局地强降水造成的灾害很多。2010年7月15日宜昌地区的强降水是在满足大尺度降水条件下受地形作用加强的局地暴雨。本文利用实况高空、地面、加密自动站、雷达以及LAPS再分析资料对背景场、低层流场、雷达回波等几个方面进行了分析。得出:冷空气南下和副热带高压的加强促进低层风场的调整,在大尺度降水条件下,地形对低层风场的辐合作用触发了局地强降水的发生。此次过程中地形对降水的触发主要有两方面的作用:一方面为地形迎风坡抬升触发作用,另一方面为地形对近地层流场的影响造成的辐合触发。 相似文献
64.
本文利用广东省气象台站的风速自记资料,计算风能资源,并分析风能资源的分布特点及规律,得到的结果是沿海岛屿风能丰富,内地风能贫乏,冬半年风能条件比夏半年好。按全省风能蕴藏量可划为三大区:沿海岛屿为风能丰富区,沿岸为风能可利用区,大陆内地和海南岛五指山区为风能贫乏区。 相似文献
65.
Relationships between Interannual and Intraseasonal Variations of the Asian-Western Pacific Summer Monsoon Hindcasted by BCC_CSM1.1(m) 总被引:4,自引:0,他引:4
LIU Xiangwen ;WU Tongwen ;YANG Song ;LI Qiaoping ;CHENG Yanjie ;LIANG Xiaoyun ;FANG Yongjie ;JIE Weihua ;NIE Suping 《大气科学进展》2014,31(5):1051-1064
Using hindcasts of the Beijing Climate Center Climate System Model, the relationships between interannual variability (IAV) and intraseasonal variability (ISV) of the Asian-western Pacific summer monsoon are diagnosed. Predictions show reasonable skill with respect to some basic characteristics of the ISV and IAV of the western North Pacific summer monsoon (WNPSM) and the Indian summer monsoon (ISM). However, the links between the seasonally averaged ISV (SAISV) and seasonal mean of ISM are overestimated by the model. This deficiency may be partially attributable to the overestimated frequency of long breaks and underestimated frequency of long active spells of ISV in normal ISM years, although the model is capable of capturing the impact of ISV on the seasonal mean by its shift in the probability of phases. Furthermore, the interannual relationships of seasonal mean, SAISV, and seasonally averaged long-wave variability (SALWV; i.e., the part with periods longer than the intraseasonal scale) of the WNPSM and ISM with SST and low-level circulation are examined. The observed seasonal mean, SAISV, and SALWV show similar correlation patterns with SST and atmospheric circulation, but with different details. However, the model presents these correlation distributions with unrealistically small differences among different scales, and it somewhat overestimates the teleconnection between monsoon and tropical central-eastern Pacific SST for the ISM, but underestimates it for the WNPSM, the latter of which is partially related to the too-rapid decrease in the impact of E1 Nifio-Southern Oscillation with forecast time in the model. 相似文献
66.
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68.
中国葡萄气候区划探讨 总被引:6,自引:0,他引:6
根据葡萄的生物学特性及其对气候条件的要求,在全国范围内选取83个站点,按照9个农业气候指标,利用模糊聚类的数学方法,将全国划分为6个不同的葡萄气候区,并就各区的气候特点和品种选择作出分区评述。 相似文献
69.
The climatological summer monsoon onset displays a distinct step wise northeastward movement over the South China Sea and
the western North Pacific (WNP) (110°–160°E, 10°–20°N). Monsoon rain commences over the South China Sea-Philippines region
in mid-May, extends abruptly to the southwestern Philippine Sea in early to mid-June, and finally penetrates to the northeastern
part of the domain around mid-July. In association, three abrupt changes are identified in the atmospheric circulation. Specifically,
the WNP subtropical high displays a sudden eastward retreat or quick northward displacement and the monsoon trough pushes
abruptly eastward or northeastward at the onset of the three stages. The step wise movement of the onset results from the
slow northeastward seasonal evolution of large-scale circulation and the phase-locked intraseasonal oscillation (ISO). The
seasonal evolution establishes a large-scale background for the development of convection and the ISO triggers deep convection.
The ISO over the WNP has a dominant period of about 20–30 days. This determines up the time interval between the consecutive
stages of the monsoon onset. From the atmospheric perspective, the seasonal sea surface temperature (SST) change in the WNP
plays a critical role in the northeastward advance of the onset. The seasonal northeastward march of the warmest SST tongue
(SST exceeding 29.5 °C) favors the northeastward movement of the monsoon trough and the high convective instability region.
The seasonal SST change, in turn, is affected by the monsoon through cloud-radiation and wind-evaporation feedbacks.
Received: 19 October 1999 / Accepted: 5 June 2000 相似文献
70.