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991.
本文介绍了一种画LC电路相轨线的方法,运用该方法画了几个LC电路的相轨线,从而表明该方法对LC电路的分析有实用价值。 相似文献
992.
万骏 《华东地质学院学报》1998,21(3):249-253
本文以512矿床为例阐述层间氧化带砂岩铀矿床,矿化富集部位与铀镭平衡变化特征的关系,铀镭平衡变化特征与地面异常的关系,重点论述了层间氧化带砂岩型铀矿床的氡异常特征,评价了地面氡法寻找层间氧化带砂岩型铀矿床的作用和意义 。 相似文献
993.
印支期构造运动在赣西北地区的早期表现特征 总被引:1,自引:0,他引:1
本文论述了印支期早期构造幕在赣西北地区的表现特征,它不但造成早三叠世地层内部沉积相突变,而且缺失中、上三叠世地层。该早期构造幕的发现,在地学上具有重要意义。 相似文献
994.
ISORROPIA: A New Thermodynamic Equilibrium Model for Multiphase Multicomponent Inorganic Aerosols 总被引:16,自引:0,他引:16
A computationally efficient and rigorous thermodynamic model that predicts the physical state and composition of inorganic atmospheric aerosol is presented. One of the main features of the model is the implementation of mutual deliquescence of multicomponent salt particles, which lowers the deliquescence point of the aerosol phase.The model is used to examine the behavior of four types of tropospheric aerosol (marine, urban, remote continental and non-urban continental), and the results are compared with the predictions of two other models currently in use. The results of all three models were generally in good agreement. Differences were found primarily in the mutual deliquescence humidity regions, where the new model predicted the existence of water, and the other two did not. Differences in the behavior (speciation and water absorbing properties) between the aerosol types are pointed out. The new model also needed considerably less CPU time, and always shows stability and robust convergence. 相似文献
995.
Numerical computations concerning geochemical processes in porous media require a knowledge of the values of the macroscopic
parameters. In the context of the interpretation of leaching tests one such parameter is the apparent macroscopic diffusivity.
In this paper, a mathematical model for dissolution in the presence of diffusion is considered. It is shown that the constant
diffusion coefficient can be identifiable when the time integral of the flux is known. Moreover, a practical algorithm for
computing the diffusion coefficient is proposed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
996.
Removal of LNAPL (oil) from an aquifer is described using a multiphase flow model. At the well boundary seepage face conditions are imposed. These conditions are implemented in a numerical model and withdrawal in a twodimensional domain is simulated for two different geometries of the oil lens and for varied values of the physical parameters. Assuming vertical equilibrium, the oil flow equation is reduced by vertical integration. The well boundary condition is approximated by imposing zero oil lens thickness. Similarity solutions of the reduced equations for the two geometries show good agreement with the numerical results in most cases. 相似文献
997.
怒江大坝建设中的各方博弈分析 总被引:1,自引:2,他引:1
尹炎 《云南地理环境研究》2005,17(2):19-23,46
在怒江上修建大坝是否可行,引起了社会各界的广泛争议。赞成者和反对者各执一词,使得怒江大坝工程的上马被迫搁浅。应用博弈论的方法可以分析在怒江大坝建设的论证过程中,中央政府、环保人士和当地人民的利益关系,并且可以证明在没有环境保护法律的保障下,环保评价的弊端。通过对各方博弈的分析,说明了政府在进行怒江大坝建设的决策过程中,必须高瞻远瞩,以全社会的可持续发展为根本出发点,同时要兼顾当地人民的利益,并要以此为基础制定出一套科学的工程建设环境评价法律。 相似文献
998.
Natural fluid phases at high temperatures and low pressures 总被引:1,自引:0,他引:1
Gas phases at low pressures and high (magmatic) temperatures have certain peculiar properties. The fluid is mainly water vapour, which is usually observed during discharging of crystal magmatic melts. At >700°C and <100 bar these peculiar properties include: formation of near ‘dry' salt melts as second fluid phase, very strong fractionation of hydrolysis products between vapour and melts, subvalence state of metals during transport processes, and high sensitivity of the gas to conditions of sublimate precipitation. Phase diagram analysis as well as results of field and laboratory experiments are presented in this article. The processes could be a model for industrial technologies to clean wastes from toxic, rare and heavy metals. Transport forms of some elements in volcanic gases are very similar to the species which were formed first in the protosolar nebula. 相似文献
999.
1000.
The study on the competitive adsorption shows that the magnitude order of metal ions adsorbed onto oxide and silicate minerals
in near-neutral solution with low ionic strength is in mole/nm2 as follows: CaCO3 > quarte > hydromuscovite > kaolinite > Ca-montmorillonite > goethite > gibbsite. These minerals can be divided into three
groups according to their surface equilibrium constantsK
M of the adsorption reactions, which are the function of the dielectric constants ε of the absorbent minerals. The relationships
between constantsK
M and mineral dielectric constants ε are described as follows: lgK
M
1
= 7.813-26.15/ε lgK
M
2
= 9.030-26.15/ε lgK
M
3
=11.63-26.15/ε for the adsorption reaction: >SO- + Mn+≥SOMn-1)+ (n = 1, 2, 3)
The first group of minerals include quartz, goethite, 1:1 phyllosilicates and other oxide minerals; the second: gibbsite,
brucite and 2:1 phyllosilicates; the third: carbonate, sulphate and phosphorate minerals. The appearance reaction constants
have a variation of magnitude ±0.5 for different metal ions with the same mineral.
This project was financially supported by the National Natural Science Foundation of China (No. 49572091). 相似文献