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991.
<正> 一、深化我院科技体制改革的必要性和紧迫性 中国地质科学院是我国地质行业专业齐全、技术力量雄厚、规模最大的综合性地质科学研究机构,创立于1956年,现隶属国土资源部。几十年来,中国地质科学院的研究机构几经调整分合,所属研究单位最多时曾达到23个,人员近7000人。建院44年来,地科院 相似文献
992.
山东省林业科学研究所 《湿地科学与管理》2000,(1):45-46
<正> 山东省林业科学研究所是以应用基础研究、应用研究和开发性研究为主的林业综合性科研机构。建所四十多年,在广大科研人员共同努力下,取得了100余项省部级以上的科研成果,为振兴山东林业,促进经济发展发挥了巨大作用。特别是改革开放以来,随着社会主义市场经济的建立和发展,科技体制改革的不断深入,全所同志解放思想,更新观念,认清形势,明确了科技发展思路。经过几年努力和探索,走出了一条适合我所实际的科技产业化道路,创造了较大的社会、经济效益。自1997年以来,全所科技企业和实体产 相似文献
993.
Effects of salinity, light and temperature on growth rates of two species of Gracilaria (Rhodophyta)
Effects of temperature, salinity and light intensity on growth rates of Gracilaria lichenoides and G tenuistipitata var. liui Zhang et Xia were tested. Eight to ten levels of each factor were first tested separately. The best growth rate was obtained under the conditions of 32~C, 30 and 240 μmol/(m2·s) for G. lichenoides, and 24℃, 20 and 200 μmol/(m2.s) for G. tenuistipitata, respectively. Then a uniform design was used to evaluate the optimal combinations of the three factors. The best conditions for the highest daily specific growth rates (% increase in wet weight) are determined to be 31.30℃, 32.10, and 287.23 μmol/(m2·s) for G. lichenoides (16.26%/d), and 25.38℃, 21.10, and 229.07 μmol/(m2·s) for G. tenuistipitata (14.83%/d), respectively. 相似文献
994.
A Study of Near- and Super-Critical Fluids Using Diamond Anvil Cell and in-Situ FT-IR Spectroscopy 总被引:2,自引:0,他引:2
The phase relation and solution structure of water and NaCl aqueous solution have been observed and examined by using the hydrothermal diamond anvil cell (HDAC) at elevated temperatures and pressures and the in situ FT-IR spectroscopy. The temperature of observations ranges from 25 to 850° C and the pressure up to 10 or 30 kb. At first, we observed the phase transition process from halite+liquid+vapour (H+L+V) to L+H, then to L (or supercritical fluid, SCF), and another path: H+L+V? L+V? L (or SCF) in heating process. By means of the visual microscope, the authors found that in the L+V immiscibility field L+V exhibits an ordered structure, i.e. a large visual cluster of solvent around ions. The liquid phase is manifested by vapour bubbles. When phase transitions are observed, the authors examined their infrared spectra by using the FT-IR microscopy simultaneously. In the case of the phase transition from liquid (L) to liquid + vapor (L+V) immisciblity field of NaCl solutions, a sudden change (strong frequency shift) of infrared spectra of the aqueous solution is observed near the critical temperature of water as the temperature is raised from 25 to 650° C. The frequency of the maximum intensity of OH symmetric and asymmetric vibration varies with respect to temperature. The sharp peak of the OH stretching vibration of the maximum intensity appears in an interval from 300 to 400° C. It is indicated that the hydrogen bonding network is weakened and broken at last near the critical point of water, which causes the aqueous solution to become more associated. Besides, a pressure indicator (a mineral or compound) was introduced to the HDAC. 相似文献
995.
XU Wenxin CHEN Minyang PANG Chunyong LI Heng Research Institute of Geology for Mineral Resources CNNC Guilin 《《地质学报》英文版》2000,74(2):316-320
Based on Pb-Pb isochron data of more than 40 Precambrian polymetallic deposits, the authors consider that there are four mineralization periods for the Precambrian copper deposits in China, and the major copper deposits were formed at about 1800 Ma; there are three mineralization periods for gold deposits formed from Archaean to Proterozoic. By studying hundreds of lead isotope data from some Mesozoic continental subvolcanic Cu and Ag polymetallic deposits and fine-disseminated gold deposits, the authors found that the calculation based on the lead single-stage evolution model or two-stage evolution model cannot give the true ore-forming ages but can provide more information about mineralization and material sources of the deposits. 相似文献
996.
YAN Chunjie SUN Yunzhi TANG Huiming Test Centre China University of Geosciences Wuhan Hubei Institute of Yangtze River Exploring Technique Ministry of Water Resources Wuhan Hubei 《《地质学报》英文版》2000,74(2):349-352
The mineral assemblage and content and surface microtextures of slipping zone soil of several landslides in the Three Gorges Reservoir District have been analyzed using the scanning electron microscope (SEM) and X-ray diffractometer (XRD). All the mineral assemblages are similar in these landslides. The main minerals are montmorillonite, illite, kaolinite, chlorite, quartz and feldspar. There are two kinds of surface microtexture in the slipping zone soil, i.e., linear scratches and arcuate scratches. Based on analyses of the changes of the microtextures, one can obtain information about the number, directions and stages of landslide movements. The authors have also studied the mechanism of landslide formation, evaluated the stability of landslides and revival possibility of ancient landslides and forecasted the activity of similar landslides in different districts. The surface microtexture features of stable landslides and mobile landslides are summarized and it is concluded that the existence of filam 相似文献
997.
UrbanizationisaworldwidetrendofdevelopmentandoneofthemaincontentsofeconomicandsocialdevelopmentstowardChina’smodernization.I... 相似文献
998.
Wang Gnanghai Chen Bozhen Senior Research Engineer China Ship Scientific Research Center 《中国海洋工程》1992,(1)
In China, a nationwide research program on fatigue behaviour of tubular joints made of China-made platform steel was carried out from 1983 to 1990, which was set by the Tubular Joint Research Committee for Offshore Structures (TJCOS) of China. This paper gives an outline of the basic properties of the China-made platform steel and fatigue test of tubular joints, including test specimens, test particulars and test results. A p-S-N curve based on the test results was established which reveals that the fatigue strength of tubular joints is fairly good. The thickness effect and effect of corrosion on fatigue strength in sea water are briefly discussed. 相似文献
999.
Global Positioning System(GPS) and Interferometric Synthetic Aperture Radar(InSAR),used for monitoring crust deformation,are found to be very promising in earthquake prediction subject to stress-forecasting.However,it is recognized that unless we can give reasonable explanations of these curious precursory phenomena that continue to be seren-dipitously observed from time to time,such high technology of GPS or InSAR is difficult to be efficiently used.Therefore,a proper model revealing the relation between e... 相似文献
1000.
Mingbo Yang Yuehu Kang Qing Zhang Institute of Geographic Sciences Natural Resource Research Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of Sciences Beijing China Earthquake Administration of Beijing Municipality Beijing China Beijing Beifang Middle School Beijing China 《地震学报(英文版)》2009,(3):301-306
This paper quantitatively analyzed groundwater table fluctuations caused by groundwater overdraft, and probed into the possibility of drawing earthquake precursory information from groundwater table variations on the background of groundwater overdraft. Main effect factors of groundwater regime in Beijing region include groundwater extraction and rainfall. The decline of groundwater table was directly related to regional groundwater overdraft. Using the method of correlation analysis, the paper analyzed the... 相似文献