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121.
近日,由河南煤化集团、中石油煤层气公司、河南省煤田地质局共同实施,旨在共同开展煤层气地面抽采试验研究、综合开发煤层气资源,力争在河南省煤层气抽采开发方面取得重大突破的河南省首个地面瓦斯抽采试验井项目顺利完工。 相似文献
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近日,河南省地勘二院在禹州市探明一大型水泥灰岩矿床,水泥灰岩资源量达3.89亿吨,禹州市境内的寒武系张夏组的鲕粒灰 相似文献
124.
采用粘性屈服模型来模拟摩耗能器的力-速度关系,建立了摩擦与粘性流体耗能器串联耗能体系的动力分析方法,为考虑框架杆件和支撑材料的几何非线性,采用增量型Rosenbrock二级三阶半隐式Runge-Kutta法求解动力方程,比较了仅有摩擦耗能器体系与串联组合耗能体系的减振效果,分析了粘性流体耗能器参数对组合耗能体系减振效果的影响。 相似文献
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126.
钯和镍的碲锑化物及其他铂族金属新矿物、新变种 总被引:3,自引:0,他引:3
中国科学院贵阳地球化学研究所铂矿研究组电子探针分析组X射线粉晶分析组选矿组 《地球化学》1974,(3):169-181
通过东北地区W岩体硫化铜镍矿床和西南地区Y岩体硫化镍矿床的地质研究工作,发现了若干铂族金属新矿物、新变种。目前,我们主要研究了钯和镍的碲锑化物,其他初步认为属铂族金属新矿物或新变种者,一并在此综合报导。 相似文献
127.
Variation of phytoplankton biomass and primary production in Daya Bay during spring and summer 总被引:11,自引:0,他引:11
Song X Huang L Zhang J Huang X Zhang J Yin J Tan Y Liu S 《Marine pollution bulletin》2004,49(11-12):1036-1044
Environmental factors, phytoplankton biomass (Chl a) and primary production of two water areas in Daya Bay (Dapeng'ao Bay and Aotou Bay) were investigated during the transition period from spring to summer. Chl a ranged from 3.20 to 13.62 and 13.43 to 26.49 mg m(-3) in Dapeng'ao Bay and Aotou Bay respectively, if data obtained during red tides are excluded. Primary production varied between 239.7 and 1001.4 mg Cm(-2) d(-1) in Dapeng'ao Bay. The regional distribution of Chl a and primary production were mostly consistent from spring to summer in both bays. Seasonal transition characters have been found in Daya Bay from spring to summer, including high values of DO, nitrate and silicate. Size structures of phytoplankton and its primary production do not change very much from spring to summer, with micro-phytoplankton dominating and contributing about 50% of the whole. In Daya Bay, phytoplankton is limited by nitrogen in spring, and by phosphate in summer. Artificial impacts are evident from high temperature effluent from nuclear power stations, aquaculture and sewage. During the investigation, a red tide occurred in Aotou Bay, with a maximum Chl a of 103.23 mgm(-3) at surface and primary production of 2721.9 mg Cm(-2) d(-1) in the red tide center. Raised water temperature and nutrient supply from land-sources help to stimulate annual red tides. 相似文献
128.
In the analysis of streamflow depletion, the Hunt (1999) solution has an important advantage because it considers a partially penetrating stream. By extending the Hunt drawdown solution, this paper presents semianalytical solutions for gaining streams that evaluate the induced stream infiltration and base flow reduction separately. Simulation results show that for a given deltah (the initial hydraulic head difference between stream and aquifer beneath the channel), the base flow reduction is in direct proportion to the product of streambed leakage (lambda) and the distance between pumping well and stream (L), and the induced stream infiltration is in inverse proportion to lambdaL. Deltah has a significant effect on the ratio of stream infiltration to base flow reduction. The results from the semianalytical solutions agree well with those from MODFLOW simulations. The semianalytical solutions are useful in the verification of numerical simulations and in the analysis of stream-aquifer interactions where water quantity or quality is concerned. 相似文献
129.