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181.
The radial basis function (RBF) interpolation approach proposed by Freedman is used to solve inverse problems encountered in well-logging and other petrophysical issues. The approach is to predict petrophysical properties in the laboratory on the basis of physical rock datasets, which include the formation factor, viscosity, permeability, and molecular composition. However, this approach does not consider the effect of spatial distribution of the calibration data on the interpolation result. This study proposes a new RBF interpolation approach based on the Freedman's RBF interpolation approach, by which the unit basis functions are uniformly populated in the space domain. The inverse results of the two approaches are comparatively analyzed by using our datasets. We determine that although the interpolation effects of the two approaches are equivalent, the new approach is more flexible and beneficial for reducing the number of basis functions when the database is large, resulting in simplification of the interpolation function expression. However, the predicted results of the central data are not sufficiently satisfied when the data clusters are far apart. 相似文献
182.
不同温度、压力条件下人造金刚石的晶体形态特征及优晶生长区的初步探讨 总被引:2,自引:0,他引:2
Crystal. habit and morphological peculiarities of synthetic diamond have been studied at various temperatures and. pressures.A diagram has been proposed based on experimental data for different erystal morphology with respect to different P.T conditions, Preliminary discussion has been given to the field of fine diamond crystal growth and a principle is presented for the optimum P-T conditions for fine diamond synthesis. 相似文献
183.
本文以表格的形式列举了经国际矿物学协会(IMA)新矿物与矿物命名委员会(CNMMN)批准、并于2004年度正式发表的新矿物共45种.其中硅酸盐19种,磷酸盐4种,砷酸盐4种,硼酸盐3种,钒酸盐2种,锗酸盐1种,碲酸盐1种,硒酸盐1种,硫化物2种,硫盐2种,锑碲化物1种,硅化物1种,氧化物和氢氧化物3种,复杂卤化物1种.文中表格依次列出了矿物名称及化学式、晶系及晶胞参数、主要粉晶数据、物理性质、光学性质、产状及共生(伴生)组合等. 相似文献
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185.
堇青石矿物学研究进展:——Ⅱ人工合成堇青石的物理性质 总被引:3,自引:1,他引:3
工业用的堇青石多为人工合成,一些堇青石是在最终材料制作之前预先合成的,一些是在材料的制作和使用过程中生成的。堇青石具有许多优良的性能,包括低的热膨胀性,优良的抗热震性,较高的机械强度,低的介电常数和高的电阻率。随着材料生成条件不同,堇青石的物理性质也有较大变化 相似文献
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188.
In the Middle East, dust storms are a persistent problem and can be easily inhaled into the mouth, nasal pharynx, and lungs due to their small size and abundance. The acute and chronic effects from exposure to this dust have not been well studied nor has the dust been characterized as to its chemical composition, mineral content, or microbial flora. Experiments were designed to study the Middle East dust as to its physical, chemical, and biological characteristics. Kuwaiti and Iraqi dust samples from different locations were collected and processed. Initial chemical and physical characterization of each sample including particle size distribution and inorganic analysis was conducted using ICP-MS for 57 different elements. 相似文献
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