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51.
发达国家禁用（限用）含磷洗衣粉的措施 总被引：14，自引：3，他引：11
在查阅国内外有关文献资料的基础上,对世界上主要发达国家－－美国,加拿大,日本,德国,英国和法国等,实施禁用（或限用）含磷洗衣粉措施的历史背景状况,实施后所取得的效果及当前存在的意见分岐作出简要的综述,结果表明,“禁磷”措施在洗衣粉中磷占入湖总磷量比例较大（２０％以上）,且目前难以兴建三级污水处理厂的湖区,对削减磷的负荷,减缓湖泊富营养化的进程,起到一定的积极作用,但解决富营养化问题的根本途径。 相似文献
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53.
A considerable portion of the territory of Afghanistan, having structures of the Mediterranean folded belt, has been subjected to a general tectonomagmatic activization over the Miocene through to the present, resulting in different (predominantly oscillating) tectonic movements, intrusive magmatism, terrestrial volcanism, mineral occurrences, and springs of carbonated and nitrous thermal water.Three types of young magmatism and volcanism products have been recognized in Afghanistan:
- 1. (1) Miocene alkaline granite intrusions, described as the Share—Arman Complex, resulted from the early orogenic stage of the Late Alpine geosynclinal troughs development and were restricted to transversal uplifts, in both the geosynclinal structures and on their extension, in the surrounding median masses. These transversal uplifts also play the role of mineralization-controlling structures.
- 2. (2) Late orogenic—Early Quaternary volcanics (the Dash-i-Nawar Complex) cropping out by the periphery of median masses and at the marginal uplifts of the Late Alpine folded area and also restricted to the transversal uplifts with the confined fault zones to them.
- 3. (3) Alkaline carbonatitic (the Khanneshin Complex) and trachybasaltic (the SarLogh Complex) Early—Middle Quaternary volcanics in the inner parts of the Central Afghanistan Median Mass and in the southeastern segment of the Turan Plateau.
54.
A plate-tectonics model of the Alpine evolution of the Caucasus is suggested. According to the model, in the Jurassic-Neocomian the Caucasian territory comprised the shelf of the East European platform, the marginal sea of the Great Caucasus, the Pontian-Transcaucasian island arc, the Anatolian-Minor Caucasian oceanic basin (Tethys) and the Iranian-Turkish microcontinent. Along the northern margin of the oceanic basin a convergent plate juncture extended. Part of the Caucasus, situated north of this plate boundary, represented the West Pacific-type active margin of the East European platform. In the Middle Cretaceous the Iranian-Turkish microcontinent collided with the Pontian-Transcaucasian island arc and as a result the Transcaucasian-Minor Asian continental block originated. In the central part of the latter an extensive Paleogene andesitic belt formed, with the Black Sea-Adjara-Trialetian and Talysh-South Caspian basaltic rift troughs on its rear (northern) side (incipient Black Sea and South Caspian basins). Major plate boundary shifted south, into the Zagros-Taurus basin, though the Anatolian-Minor Caucasian suture zone remained mobile in the Upper Cretaceous and Paleogene. From the Oligocene, under conditions of ongoing convergence of the Eurasian and Afro-Arabian continental blocks, the present-day intracontinental mountainous foldbelt has developed. 相似文献
55.
56.
GPS���ܵ��㶨λ��Ӱ������ʱ������ؼ���ʩ���� 总被引：1，自引：0，他引：1
??GPS??????λ?????????У?????????????????估???????λ??????????????????????????????????????????λ????????????λ?????????????????????????????????????????????????????????伸?ι?????????????????????????????Щ??????????????????????????????????????????????????????? 相似文献
57.
58.
季风低压对台风生成影响的观测分析 总被引：1，自引：1，他引：0
选取2007年和2009年发生的4个季风低压个例, 利用FNL资料和CMORPH卫星反演的降水资料, 采用多尺度环流分析法, 对西北太平洋季风环流的多尺度特征进行了分析, 研究季风低压对台风生成的可能影响。分析发现:季风低压生成于季风槽中, 其天气尺度波列的气旋性环流中。虽然以季风槽为特点的低频环流为台风生成提供大尺度气候条件, 但是季风低压通过进一步提供较大的正相对涡度, 可以有效减小Rossby变形半径, 促进热带低压中中尺度对流系统的相互作用和合并, 有利于台风的生成。 相似文献
59.
为了对地基全天空红外测云仪获得的云图进行分类,该文从压缩感知理论出发,提出了一种利用云图灰度稀疏性进行云状识别的新方法。首先运用典型云图样本构造冗余字典,然后通过梯度投影 (GPSR) 算法和正交匹配 (OMP) 算法求取测试样本在冗余字典中的l1范式最优解,最后利用残差法和稀疏比例法对云状进行判别并输出。采用压缩感知理论进行云状识别,降低了对特征提取技术的要求,为云状的自动识别提供了新思路,对典型波状云、层状云、积状云、卷云和晴空的总体识别率分别达到75%,91%,70%,85%和93%,平均识别率为82.8%。 相似文献
60.
The results of geotechnical explorations, engineering geological investigation (including laboratory and in situ tests) and
field observations have been used, along with borehole logging charts, to obtain the rock mass geotechnical data. Based on
the data, the rock mass along the Sabzkuh water conveyance tunnel route was classified by rock mass rating (RMR), Q-system
(Q), rock mass index (RMi) and geological strength index (GSI) (3 methods). A new series of correlations were established between
the systems based on the data collected from the study area. These relationships were then compared with those reported in
the literature, and two new relations were recommended. The classifications were utilized to calculate mechanical properties
(rock mass strength and deformation modulus) of the rock mass along the tunnel according to available empirical relations,
and to distinguish the upper-bound and lower-bound relations. 相似文献