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101.
本文介绍了计算机处理和光学处理相结合的信息提取方法并得到显著效益。根据澳门海域和磨刀门海域工程建设中的实际需要,成功地运用遥感影像信息为澳门海域工程物理模型试验提供了模型水流流态与原型水流流态相似性的验证,为磨刀门海域围垦工程提供了水下潜坝的动态影像信息,并取得了较好的社会效益和经济效益。  相似文献   
102.
103.
碳棒涂膜式PVC膜铯离子选择电极的研制和应用   总被引:3,自引:0,他引:3  
但德忠  谭明勇 《矿物岩石》1990,10(4):105-108
本文作者研制成功以四苯硼铯为活性物质的碳棒涂膜式PVC膜铯离子选择性电极。电极最佳膜组成:四苯硼铯5mg,邻苯二甲酸二丁酯0.4ml,硝基苯0.2ml,PVC粉0.2g。电极性能优良,制作简单,操作方便。结合大粒度磷钼酸铵和结晶形锑酸分离K~+,Na~+,巳将此电极用于卤水样中铯的测定,结果令人满意。  相似文献   
104.
The vibrational properties of metastable Ca-GeO3 perovskite are investigated as a function of temperature using Raman scattering. Mode-assignments are derived from polarized spectra of optically oriented single crystals. Neither symmetry-breaking structural transformations nor soft-mode behavior is revealed in the Raman spectra between room temperature and 650° C. Only a small decrease in the local static octahedral tilt angles can be inferred from the Raman data over this temperature range. A Landau extrapolation of the lowest frequency Ag modes suggests that these modes become critical near 2000° C, a temperature that is above the extrapolated zero pressure melting point.  相似文献   
105.
Abstract. WMPLUME is an analytic dispersion model based on the Wilson and Miller equation presented here in a program for the HP-41CV handheld, programmable calculator, the HP-41CX, or the HP-41C with four memory modules. The user specifies the spacing and extent of the field of observation points. The calculator can handle up to 36 fully penetrating, continuous injection well sources or a lesser number of discontinuous wells. The time of observation can be changed easily and sources can be added or deleted readily. The code is prepared for use with or without a printer attached to the calculator.  相似文献   
106.
The style of deformation in thin-skinned fold-and-thrust belts is critically dependent upon the resistance to sliding along the detachment between the mass of deforming sediments and the underlying rocks. Evaporites can provide an extremely weak horizon within which a basal detachment can form and along which only a relatively small shear traction can be supported. Fold-and-thrust belts that form atop a salt layer, such as the Appalachian Plateau, the Franklin Mountains in northwestern Canada, and the Jura of the Alps, among others, share several readily observable characteristics. As predicted by a simple mechanical model for fold-and-thrust belts, a detachment in salt permits a thrust belt to have an extremely narrow cross-sectional taper. In addition, predicted orientations of the principal stress axes over a salt décollement are consistent with the commonly observed lack of a consistently dominant vergence direction of structures within the thrust belt. Other common attributes of salt-basal thin-skinned deformation include the presence of several widely but regularly spaced folds and abrupt changes in deformational style at the edge of the salt basin.  相似文献   
107.
Dan H. Allen 《Ground water》1986,24(6):791-797
Abstract. Hantush (1967) provided time-dependent equations for describing ground-water mounds resulting from axisymmetric recharge. Because these equations contain the well function, they cannot be solved explicitly for the several variables employed in terms of the known mound height. Newton's method provides a means to achieve solutions for specific yield, hydraulic conductivity, time, or radius. An additional routine is provided which searches for the second solution in the case in which the inverse solution for hydraulic conductivity is doublevalued. The iterations can be performed on an HP-41C handheld calculator with three memory modules. The code is provided and will run with or without the printer attached.  相似文献   
108.
隋波  隋戈  隋丹 《地理科学》2007,27(Z1):69-77
探讨了副热带高压、西风带环流、极涡指数的年际和年代际变化规律,揭示了来自副热带、中纬度和极地的大气环流系统的强迫对中国夏季降水的影响.结果表明初夏,当纬向环流指数偏弱时,中国东北和华北大部分地区降水量偏多,这表明东亚中高纬地区盛行阻塞和冷涡偶极子系统,呈有利于东北的冷涡雨季形势;盛夏,西太平洋副热带高压脊线位置和亚洲区极涡强度指数与中国同期降水量场相关波列,均为自北向南呈"-、 、-、 "经向波列分布;春季亚洲区极涡强度、亚洲纬向环流指数、西太平洋副热带高压北界位置以及前一年冬季北半球极涡强度指数与盛夏中国降水量相关显著.中国盛夏降水带,从东北地区开始,由北向南分4个雨带.  相似文献   
109.
The 0S2~0S54 spheroidal modes of Earth’s free oscillations, triggered by the great Sumatra-Andaman earthquake of 26 December 2004 are retrieved from VHZ data recorded by seven upgraded stations of China Digital Seismograph Network (CDSN). We compare these spheroidal modes with theoretical free oscillation spectra calculated from the Preliminary Reference Earth Model (PREM) and find a coincidence between their periods. Spectral splitting phenomenon is observed obviously in 0S2, 0S3, 0S4, 2S1 and 1S2 free oscillation modes. What is most noticeable is that the oscillation mode 2S1 is reported for the second time (the first time by Rosat et al) without any data stacking. We simulated the split singlet of 0S2 mode on seven CDSN stations based on general focal mechanism and seismic moment of the earthquake. The result shows that seismic moment of the earthquake can reach 1023 N.m. We also find that the recording of Earth’s free oscillations carries abundant information of source mechanism and earthquake location, which is applicable to the detailed study of source rupture parameters.  相似文献   
110.
使用共轭码技术,构造了中尺度模式的伴随模式,研究了模式侧边界条件。基于伴随模式技术的原理,设计了伴随同化和Derber同化方法两套方案;下降算法采用共轭梯度法,使用准真实资料,进行子同化数值试验和预报试验。结果表明,两套同化方案都取得了一定的同化效果,Derber同化方法比伴随同化更令人满意。证明了变分同化是提高预报准确率的一种非常有效的手段。  相似文献   
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