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21.
赣南钨矿资源状况及新一轮找矿战略的基本思路   总被引:3,自引:1,他引:2  
张声波 《矿产与地质》2003,17(Z1):292-293
简要总结了赣南钨资源的探明储量、矿业开采情况及资源现状,从中说明新一轮找矿的必要性,提出了"立足三保、资料开发、更新观念、探边摸底找盲、尾砂开发利用"的找矿思路.  相似文献   
22.
张声波 《矿产与地质》2001,15(Z1):445-449
兴国环形断裂对岩浆岩及金银矿的产出具有控制作用,其空间展布格局控制岩浆岩及金银矿带的展布方向,其派生的次级主干断裂控制金银矿田的产出,褶皱构造及其派生的走向断裂、层间构造破碎带联合控制金银矿床定位.果子坳、金田坑-黄金坑为找矿靶区.  相似文献   
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浙江瓯江口南岸潮滩相带的时空变化   总被引:6,自引:0,他引:6  
谢钦春 Berg.  GW 《地理学报》1994,49(6):509-516
瓯江口南岸潮滩可分为三个沉积地貌相带:高潮滩物质由砂、泥混合沉积组成,沿岸沙堤增长;中潮滩物质以砂质为主,坑、洼地貌遍布,滩脊发育,是潮滩中最活跃,对水动力条件反映最敏感的相带;低潮滩物质由泥质组成,滩面平缓,是稳定的淤积带。潮滩相带的沉积物、地貌特征具有明显的时空变化,瓯江入海的水沙对瓯江口南岸潮滩演变产生明显的影响。  相似文献   
25.
江西省国有大中型钨矿山经过“关闭破产,转制重组”后重现了生机,但资源现状仍不容乐观。文章根据钨矿山的现状,从特定的成矿条例到钨矿山边深部和外围以及钨矿床共伴生矿产等方面分析江西省钨矿山资源潜力,提出矿山今后加强接替资源勘查等四条发展对策和措施。  相似文献   
26.
针对目前海洋观测网络通信距离、功耗、复杂度、抗干扰能力、成本之间的矛盾,提出了一种基于LoRa(long range)的海洋多功能信标组网观测系统。通过运用新型的LoRa调制技术,采用星型链路网络对多功能信标进行组网设计,并结合北斗通信,构建了一套覆盖范围广、功耗低,组网简单,抗干扰性强的海洋监测网络系统,能够有效实现近海和远海的全范围覆盖,同时降低了组网的成本。通过对多功能信标的低功耗设计,可有效降低信标功耗,延长了工作周期。通过室内和室外的模拟实验,验证了组网通信的有效性,以及远距离传输数据特性,为信标的升级设计和海洋组网观测打下了基础。  相似文献   
27.
Cox MH  Su GW  Constantz J 《Ground water》2007,45(2):187-195
Commonly measured water quality parameters were compared to heat as tracers of stream water exchange with ground water. Temperature, specific conductance, and chloride were sampled at various frequencies in the stream and adjacent wells over a 2-year period. Strong seasonal variations in stream water were observed for temperature and specific conductance. In observation wells where the temperature response correlated to stream water, chloride and specific conductance values were similar to stream water values as well, indicating significant stream water exchange with ground water. At sites where ground water temperature fluctuations were negligible, chloride and/or specific conductance values did not correlate to stream water values, indicating that ground water was not significantly influenced by exchange with stream water. Best-fit simulation modeling was performed at two sites to derive temperature-based estimates of hydraulic conductivities of the alluvial sediments between the stream and wells. These estimates were used in solute transport simulations for a comparison of measured and simulated values for chloride and specific conductance. Simulation results showed that hydraulic conductivities vary seasonally and annually. This variability was a result of seasonal changes in temperature-dependent hydraulic conductivity and scouring or clogging of the streambed. Specific conductance fits were good, while chloride data were difficult to fit due to the infrequent (quarterly) stream water chloride measurements during the study period. Combined analyses of temperature, chloride, and specific conductance led to improved quantification of the spatial and temporal variability of stream water exchange with shallow ground water in an alluvial system.  相似文献   
28.
首先介绍了非结构构件的分类;评述了单点支撑非结构构件抗震计算方法,指出等效侧力法缺乏系统的理论和实验研究支持,而楼面反应谱法不便于工程人员应用;讨论了单点支撑非结构构件隔震问题的特殊性和研究现状;最后指出对于一般单点支撑非结构构件,除了探索简单准确的抗震计算方法还应注重制定有效的构造措施;对于重要设备,应该在充分考虑设备隔震减震特殊性的基础上开发专门的隔震减震器,并应重视半主动,主动控制技术应用的研究。  相似文献   
29.
We discuss the voltammetric methods that are used to assess metal-organic complexation in seawater. These consist of titration methods using anodic stripping voltammetry (ASV) and cathodic stripping voltammetry competitive ligand experiments (CSV-CLE). These approaches and a kinetic approach using CSV-CLE give similar information on the amount of excess ligand to metal in a sample and the conditional metal ligand stability constant for the excess ligand bound to the metal. CSV-CLE data using different ligands to measure Fe(III) organic complexes are similar. All these methods give conditional stability constants for which the side reaction coefficient for the metal can be corrected but not that for the ligand. Another approach, pseudovoltammetry, provides information on the actual metal-ligand complex(es) in a sample by doing ASV experiments where the deposition potential is varied more negatively in order to destroy the metal-ligand complex. This latter approach gives concentration information on each actual ligand bound to the metal as well as the thermodynamic stability constant of each complex in solution when compared to known metal-ligand complexes. In this case the side reaction coefficients for the metal and ligand are corrected. Thus, this method may not give identical information to the titration methods because the excess ligand in the sample may not be identical to some of the actual ligands binding the metal in the sample.  相似文献   
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