柴达木盆地盐湖形成演化与水体来源关系的地球化学初步模拟:Pitzer模型的应用

利用Pitzer模型，对柴达木盆地盐湖、地表河水以及地表河水同深部来源的CaCl2水体以不同的比例混合后进一步演化的结晶路线进行了研究。结果表明，柴达木盆地硫酸镁亚型盐湖的结晶路线可分为四类，氯化物型盐湖的结晶路线可分为两类，他们的形成不可能是地表河水蒸发演化到一定阶段的产物。地表河水同深部来源CaCl2水体以不同比例混合掺杂后水体水化学类型及析盐途径各不相同，它们同盒地内不同盐湖的水化学类型及其析盐途径具有很好的对应关系，说明柴达木盆地盐湖的形成同盒地内存在的两种水体－地表河水和深部来源CaCl2水体有着密切的关系。     

西藏扎布耶盐湖卤水演化的Pitzer模型模拟

扎布耶盐湖是西藏高原代表性的富锂硼碳酸盐型盐湖。本文利用Pitzer模型模拟计算了西藏扎布耶盐湖冬季与夏季卤水、补给河流-泉水的低温(2℃)、常温(25℃)和高温(50℃)蒸发结晶过程,结果表明,扎布耶盐湖卤水可以由现代成分的河流-泉水蒸发浓缩形成,扎布耶盐湖的沉积组合与河泉水蒸发浓缩的矿物结晶规律吻合;而冬、夏卤水蒸发模拟结果与卤水蒸发实验结果基本吻合,但对矿物结晶顺序、矿物组合规律以及温度-季节性成分变化的影响等方面,提供了更多更详细的数据与认识。说明Pitzer模型对研究西藏富锂硼碳酸盐型盐湖的地球化学成因和盐田工艺都具有重要参考价值。     

任意盐度地下水中离子活度系数运算模型

本文把Ｐｉｔｚｅｒ模型引入到水文地球化学的研究领域，以求解决在利用水文地球化学理论研究任意盐度，尤其是中、高盐度地下水平化学组分的分布，变化特征以及矿物溶解和沉淀状态方面所涉及到离子活度系数的确定问题。文中利用模型对我国东部某盆地地下水水中的离子活度系数进行了实际运算。结果表明。Ｐｉｔｚｅｒ模型能有效地评价任意盐度，尤其是中、高盐度地下水中的离子活度系数．     

Experiment and Pitzer Model Prediction for the Solid + Liquid Equilibria of the Ternary System LiCl–CaCl2–H2O

正1 Introduction Lithium resources are widely distributed in the oilfield brine from the Nanyishan district in the Qaidam Basin(Fan et al.,2007).The investigation of the thermodynamics and phase diagram of the brine system is valuable in providing the theoretic foundation and scientific guidance in the comprehensive exploitation of the mixture salts effectively.Comprehensive     

NaCl—H_2O溶液包裹体的密度式和等容式及其应用

由于含盐类包裹体不能应用现有的状态方程求解,作者根据实验数值,采用最小二乘法等,得到含盐度(wt%)≤25的NaCl-H_2O溶液包裹体的密度式和等容式。只要测定出包裹体的均一温度和含盐度,代入密度式,即可计算包裹体中的流体密度。再由此密度、含盐度的等容式,进一步可求得包裹体的形成温度和压力。最后,作者列举了三个实例。     

CaCl2溶液对不同黏土基防渗墙渗透性的影响

在垃圾填埋场和场地污染防治工程中,黏土基防渗墙作为原位屏障,已广泛应用于隔离污染物与控制污染地下水的迁移。由黏土与地层混合形成的防渗墙与CaCl2溶液相互作用后,其渗透性会发生怎样的变化。针对这一问题,使用福建标准砂模拟砂性地层,以4种黏土作为混合材料,通过混合、浇筑和固结以后,对其渗透系数和水分特征曲线进行了实测。结果表明,在10%黏土添加量下,当4种砂-黏土混合土经0.2 mol/L CaCl2溶液渗透稳定后,其渗透系数相比渗透液为自来水时都有不同程度的增大,但渗透系数增大的倍数没有超过10。此外,CaCl2溶液在4种砂-黏土混合土中渗透稳定后试样的孔隙率没有发生较大变化,只是小幅地减小了。试验结果分析认为,钙离子与黏土矿物颗粒表面的单价阳离子发生了置换反应,使扩散双电层厚度减小,结合水含量降低,因而有效孔隙率增加,可能是宏观上造成渗透系数变大的主要原因。     

各向异性密度流模型及其验证

针对密度流流动各向异性的特性,采用非线性k-ε模式求取雷诺应力,结合RNG模型及浮力修正建立了三维密度流模型.应用该三维模型计算了水库温差异重流,分析了温差异重流演进过程,并就流速分布与水温下泄过程与实测资料进行了比较.结果表明,所建模型由于引入非线性RNG模式,能有效反映密度流的各向异性特性,较好地模拟了流场和温度场强烈耦合的水库温差异重流,能准确预测温度分层过程与异重流潜行时间,具有较高精度.     

原位低温拉曼光谱技术在人工合成CaCl2-H2O和MgCl2-H2O体系流体包裹体分析中的应用Ⅱ:低温下流体包裹体相变行为的研究

本文利用低温原位拉曼技术,对CaCl2-H2O体系和MgCl2-H20体系人工合成流体包裹体进行了研究.结果表明:对于盐浓度不同的溶液而言,可采用不同的冷冻方式有效采集低温拉曼光谱;通过系统采集不同温度下的拉曼光谱,可以直接准确地测定包裹体中流体的成分和低温相变过程.人工合成包裹体原位低温拉曼光谱的研究,为将该技术应用于天然包裹体分研究奠定了理论基础,可以预见,该技术必将在流体包裹体研究领域发挥其它方法不可替代的重要作用.     

原位低温拉曼光谱技术在人工合成CaCl2-H2O和MgCl2-H2O体系流体包裹体分析中的应用II：低温下流体包裹体相变行为的研究

本文利用低温原位拉曼技术,对CaCl2-H2O体系和MgCl2-H2O体系人工合成流体包裹体进行了研究。结果表明：对于盐浓度不同的溶液而言,可采用不同的冷冻方式有效采集低温拉曼光谱;通过系统采集不同温度下的拉曼光谱,可以直接准确地测定包裹体中流体的成分和低温相变过程。人工合成包裹体原位低温拉曼光谱的研究,为将该技术应用于天然包裹体分研究奠定了理论基础,可以预见,该技术必将在流体包裹体研究领域发挥其它方法不可替代的重要作用。     

Predictive phase equilibria for the aqueous ternary system(Li_2SO_4 + K_2SO_4 + H_2O) from 273.15 to 373.15 K

正1 Introduction Many variable temperature chemical models were developed to predict mineral solubility in the natural waters(Na+,K+,Ca2+,Mg2+//Cl-,SO42-–H2O)in the temperature range below 298.15 K(to near 213.15 K)and(Na+,K+,     

利用H2O-NaCl-CaCl2体系水盐化合物和冰的融化温度计算NaCl/（NaCl＋CaCl2）比值和盐度的方程

The composition of fluid inclusions in the H2O-NaCl-CaCl2 system has been generally graphically estimated using the melting temperatures of hydrohalite （ Tm-HH ） and ice （ Tm-ice）. Here we present two equations that can be used to calculate the relative proportion of NaCl （ i. e. , NaCL/[ NaCl ＋ CaC12 ] , or XNacl ） and the total salinity （ i. e. , NaCl ＋ CaCl2, wt% ） for fluid inclusions with ice as the last melting phase. XNacl can be calculated from Tm-HH using the following equation： y = （a＋bx）^-1/c where y is XNacl, x is Tm_HH , a =0. 33124402, b =-0. 031518028, and c =0. 22932736. In the cases where only Tm-ice is measured and Tm-HH is not known, Tm-ice can be used as the maximum possible Tm-HH to calculate the maximum value of XNacl using the above equation. In these cases, the following equation can be used to calculate the maximum total salinity： y=（a＋bx＋cx2） l where y is salinity, x is Tm-HH , a =0, 057184817, b =0. 00078565757, and c = 5. 7262766E-6. Because the isothems in the field of ice are sub-parallel to the NaCl-CaCl2 binary side in the H2O-NaCl-CaCl2 ternary system, the errors in salinity calculation introduced by the above approximation are small （ less than 2 wt% ）. A Windows program for calculation of XNacl and salinity is available at ： http ：//uregina. ca/-chiguox.     

中高盐度NaCl—H2O包裹体的密度式和等容式及其应用

由于现有的盐水溶液热力学状态方程比较复杂,对于盐水包裹体使用很不方便.笔者在已推导的低盐水包裹体热力学公式基础上,根据实验数值,采用数学拟合法,得到中高盐度(≥23.3%)NaCl-H2O溶液包裹体较精确的流体密度计算式:ρ(g/cm3)=A+B·th+C·th2(A=A0+A1·w+A2·w2;B=B0+B1·w+B2·w2:C=C0+C1·w+C2·w2)和包裹体等容式:p(×105Pa)=a+b·t+c·t2.当测定出包裹体的均一温度(th,℃)和含盐度(w,%),代入密度式即可计算包裹体的流体密度.再找出此密度、盐度的等容式中参数(a、b、c),将这一等容式和其他公式联立,可求得包裹体的形成温度和压力.本文还列举了利用密度式和等容式计算的3个实例.     

Semi-two-dimensional numerical model for river morphological change prediction: theory and concepts

This paper presents a new numerical model for river morphological predictions. This tool predicts vertical and lateral cross-section variations for alluvial rivers, which is an important task in predicting the associated hazard zone after a flood event. The Model for the HYdraulics of SEdiments in Rivers, version 1.0 (MHYSER 1.0) is a semi-two-dimensional model using the stream tubes concept to achieve lateral variations of velocity, flow stresses, and sediment transport rates. Each stream tube has the same conveyance as the other ones. In MHYSER 1.0, the uncoupled approach is used to solve the set of conservation equations. After the backwater calculation, the river is divided into a finite number of stream tubes of equal conveyances. The sediment routing and bed adjustments calculations are accomplished separately along each stream tube taking into account lateral mass exchanges. The determination of depth and width adjustments is based on the minimum stream power theory. Moreover, MHYSER 1.0 offers two options to treat riverbank stability. The first one is based on the angle of repose. The bank slope should not be allowed to increase beyond a certain critical value supplied to MHYSER 1.0. The second one is based on the modified Bishop’s method to determine a safety factor evaluating the potential risk of a landslide along the river bank.     

一维-二维耦合的河湖系统整体水动力模型

为对自然界中的复杂水流系统进行整体水动力数值模拟,建立了适用于河湖系统的一维-二维耦合模型.将河网计算中用于处理河段间耦合的汊点水位预测校正法应用到一维-二维耦合边界的处理中,即耦合边界水位预测校正法.该方法具有一维、二维模型计算完全独立,可有效利用现有模型的优点.与传统一维-二维耦合处理方法相比,耦合连接条件的满足程度较高且可通过对计算容差的调整进行有效控制.利用理想及实际例子进行了计算验证,结果表明该方法具有较好的实用性.     

Analytical model for the prediction of building deflections induced by ground movements

The objective of this study is to develop an analytical model that can predict the building‐relevant deflections induced by tunnelling or mining subsidence. The model takes into account soil–structure interactions due to differences in stiffness between the ground and the building. The ground is modelled by the Winkler model with an initial ground curvature equivalent to the free‐field ground movements. The building is modelled by a horizontal beam with uniform loading. The static and cinematic equilibrium of both the ground and the building are then calculated to assess the final building and ground shape, and the building deflection is derived. The resulting analytical model is used to investigate the influence of the ground and the building's mechanical properties, the building load and the initial value of the free‐field ground curvature (hogging or sagging). The model appears to be more comprehensive than those reported elsewhere that address the problem with numerical models. In particular, the analytical model makes it possible to distinguish two different final situations—with continuous or discontinuous contact between the ground and the building. The model is compared with numerical results and used to analyse a case study. Copyright © 2010 John Wiley & Sons, Ltd.     

天然沸石对提高TiO2光催化活性的作用

以天然沸石为载体,研究了其负载TiO2后对甲基橙溶液的光催化降解效果,探讨了TiO2与沸石的结合类型。通过对负载前后反应动力学模式变化的研究,阐释TiO₂/沸石体系的光催化反应进程。从复合前后样品的AFM、IR、发射光谱变化上看,部分TiO₂与沸石载体形成了新的Ti－O－Si或Ti－O－Al的化学键。光催化实验结果和动力学分析显示,在反应的初始阶段,当TiO₂中引入多孔的沸石载体后,催化剂对甲基橙的降解过程由原来纯粹的吸附控制模式向反应控制模式转变,但还没有达到纯粹的反应控制的程度。沸石载体是通过提高吸附过程的速率,来提升初始阶段的光催化反应速率（R₀）的。     

Density Calculation for NaCl-H2O Solutions in the Liquid-Solid Two-Phase Field in NaCl-H2O Three-Phase Inclusions

Three-phase NaCl-H₂O fluid inclusions featuring halite dissolution temperature（Tm）higher than vapor bubble disappearance temperature（T_h） are commonly observed in porphyry copper/molybdenum deposits,skarn-type deposits and other magmatic- hydrothermal ore deposits.Based on |ΔV₁|（the absolute value of volume variation of NaCl-H₂O solution in a heating or cooling process of inclusions）= |ΔV_s|（the absolute value of volume variation of the halite crystal in a heating or cooling process of inclusions） and on the principle of conservation of the mass of NaCl and H₂O,we systematically calculated the densities of NaCl-H₂O solutions in the solid-liquid two-phase field for temperatures（T_h） from 0.1℃ to 800℃ and salinities from 26.3 wt%to 99.2wt%.Consequently for the first time we obtained the upper limit of the density of NaCI-H₂O solutions in the solid-liquid twophase field for T_bm inclusions with variant salinities.The results indicate that for inclusions of the T_hm type with the same T_h,the higher the T_m or salinity is,the higher the density of the NaClsaturated solution will be.If a group of fluid inclusions were homogeneously trapped,they must have the same T_h value and the same T_m or salinity value.This may be used to distinguish homogeneous,inhomogeneous,and multiple entrapments of fluid inclusions.     

二维水动力模型的并行计算研究

建立了二维水动力并行模型;针对MPI不能实现进程迁移现状,自主开发了并行通讯平台,平台机群负载平衡采用基于蚁群算法的人工智能算法,并根据模型需要制定了相关通讯协议;对长江内江段进行数值模拟,结果表明当网格数一定时,存在一最优客户端数,当客户端数小于最优客户端数时,并行算法所需时间小于串行算法时间,并随着客户端数增加,所需时间也逐渐减少;反之,所需时间则逐渐增大。