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991.
On 23 July 2009, a catastrophic debris flows were triggered by heavy rainfall in Xiangshui gully, Kangding county, southwestern China. This debris flow originating shortly after a rainstorm with an intensity of 28 mm per hour transported a total volume of more than 480×103 m3 debris, depositing the poorly sorted sediment including boulders up to 2-3 m in diameter both onto an existing debris fans and into the river. Our primary objective for this study was to analyze the characteristics of the triggering ra...  相似文献   
992.
东明县农村宅基地管理中,非法占地、非法转让土地、超面积占地、一户多宅、擅自改变宅基地用途和批新不交旧等各种违法行为普遍存在,造成了农村宅基地管理混乱的局面。针对存在的问题,提出了加强法制宣传力度,制定政策抓管理落实,节约挖潜整治土地资源,推进城乡一体化发展等对策建议。  相似文献   
993.
In this paper, we conduct a new statistical study on the temporal distribution of the Global Positioning System Total Electron Content (GPS TEC) anomalies prior to the earthquakes with magnitude M≥7.0 in the global area during 2003–2012 by the method of statistical analysis. The temporal distribution of the ionospheric TEC anomalies prior to the earthquakes with magnitude M≥7.0 is for the first time studied. It has been observed that the ionospheric negative anomalies mainly occur in one week prior to the earthquakes, and only when the magnitude is greater than or equal to 7.6, the ionospheric anomalies will have the greatest probability of occurrence in the afternoon to sunset (i.e. between 12:00 and 18:00 local time). They last for approximate 2 hr, but the chance of detecting the significant enhancement in the ionospheric TEC seems not to be a function of time and there is no clear tendency for positive anomalies. In addition, the relationship of the occurrence rate of pre-earthquake ionospheric anomalies and the magnitude of the earthquake is discussed, and it is found that the observed ionospheric TEC anomalies within several days before the earthquakes are highly likely to be related with the earthquakes because the occurrence rate of pre-earthquake ionospheric anomalies seems to increase slightly with the earthquake magnitude increasing.  相似文献   
994.
China will establish a 2-meter space-based astronomical telescope. Its main science goals are performing a sky survey for research about dark matter and dark energy, and high resolution observations. Some experts suggest that this space telescope should be installed inside the Chinese space station. In accord with this suggestion we put forward our first configuration, i.e., to adopt a coud′e system for this telescope.This coud′e system comes from the Chinese 2.16 m telescope's coud′e system, which includes a relay mirror so that excellent image quality can be obtained. In our second configuration, we suggest that the whole space telescope fly freely as an independent satellite outside the space station. When it needs servicing, for example, changing instruments, refilling refrigerant or propellant, etc., this space telescope can fly near or even dock with the core space station. Although some space stations have had accompanying satellites, the one we propose is a space telescope that will be much larger than other accompanying satellites in terms of weight and volume. On the basis of the second configuration, we also put forward the following idea: the space station can be composed of several large independent modules if necessary.  相似文献   
995.
The Moon-based Ultraviolet Telescope(MUVT) is one of the payloads on the Chang'e-3(CE-3) lunar lander. Because of the advantages of having no atmospheric disturbances and the slow rotation of the Moon, we can make long-term continuous observations of a series of important celestial objects in the near ultraviolet band(245~340 nm), and perform a sky survey of selected areas, which cannot be completed on Earth. We can find characteristic changes in celestial brightness with time by analyzing image data from the MUVT, and deduce the radiation mechanism and physical properties of these celestial objects after comparing with a physical model. In order to explain the scientific purposes of MUVT, this article analyzes the preprocessing of MUVT image data and makes a preliminary evaluation of data quality. The results demonstrate that the methods used for data collection and preprocessing are effective, and the Level 2A and 2B image data satisfy the requirements of follow-up scientific researches.  相似文献   
996.
针对人工影响天气飞机播云作业效果评估需求,提出一种基于拉格朗日粒子扩散模式FLEXPART-WRF的催化剂催化范围模拟评估方法.以典型催化剂碘化银为例,开发催化剂物理化学特性参数清单模块,结合飞机播云特点和模式源项特点,将飞机不规则线性播撒方式离散化为连续移动点源播撒方式,实现模式对飞机播云的模拟能力.通过对一次飞机播云作业的模拟试验,证实了模拟评估方法的可行性和有效性.  相似文献   
997.
The analysis of the protein and carbohydrate in P-POM (Plankton and Particulate Organic Matter) samples collected from the fishing ground in Minnan-Taiwan Bank in five voyages (April, June, July, August and November, 1988) shows that the protein and carbohydrate contents and amounts in samples from four stations (501, 401, 301, 201) along the coast and another four stations (404, 304, 403, 204) south and southeast of the shoal were higher than those in April and November, indicating that this phenomenon is related to the upwelling in the two regions in summer .  相似文献   
998.
This study on the nutritive indexes (total nitrogen, amino acids, crude fats, inorganic elements, unsaturated fatty acids) of meat, male and female reproductive gland ofPortunus trituberculatus showed that their nutritive value is in the order meat>female reproductive gland>male reproductive gland and that they do not raise the total cholesterol (TC) and triglyceride (TG) contents of the serum of the animals which eat them but increase the contents of high density lipoprotein cholesterol (HDL-C) in the animal's blood. These findings implied that people who have high blood lipid and aortic atheroma can safely use them as food. This study showed thatP. trituberculatus has high nutritive value.  相似文献   
999.
We present new observations of the interactions of two close, but distinct, Hα filaments and their successive eruptions on 5 November 1998. The magnetic fields of the filaments are both of the sinistral type. The interactions between the two filaments were initiated mainly by an active filament of one of them. Before the filament eruptions, two dark plasma ejections and chromospheric brightenings were observed. They indicate that possible magnetic reconnection had occurred between the two filaments. During the first filament eruption, salient dark mass motions transferring from the left erupting filament into the right one were observed. The right filament erupted 40 minutes later. This second filament eruption may have been the result of a loss of stability owing to the sudden mass injection from the left filament. Based on the Hα observations, we have created a sketch for understanding the interactions between two filaments and accompanying activities. The traditional theory of filament merger requires that the filaments share the same filament channel and that the reconnection occurs between the two heads, as simulated by DeVore, Antiochos, and Aulanier (Astrophys. J. 629, 1122, 2005; 646, 1349, 2006). Our interpretation is that the external bodily magnetic reconnection between flux ropes of the same chirality is another possible way for two filament bodies to coalesce. Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users.  相似文献   
1000.
本文论述了金红石的地质产状、化学成分、粒度的概率分布、红外光谱、X射线衍射等特征及金红石成因,对本矿床成因研究及开发利用有一定意义。  相似文献   
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