IMPROVEMENT OF A GLOBAL SPECTRAL MODEL BY INTRODUCING THE SECONDLAW OF THERMODYNAMICS

The second law of thermodynamics has never been taken into account in the traditional hydrodynamics and numer-ical weather prediction models,which is a serious oversight in the history of mechanics.Introducing the thermodynamicirreversibility into the hydrodynamic systems,the theory and method proposed in this study would not only lead theoutputs of a numerical weather prediction model to noticeable improvement,but lead the structure of hydrodynamics todeepgoing transformation.     

一种快速制备不同含水饱和度岩石试样的方法

岩石的含水饱和度对其力学参数有着较大的影响,针对目前关于制备不同含水饱和度岩样普遍存在着精度低、时间长、岩样含水分布不均匀等问题,根据化学-热力学原理,提出一种快速有效制备不同含水饱和度岩样的方法。该方法通过调节放置有岩样的恒湿负压环境的湿度,从而精确控制岩样最终稳定时组分水的逸度,以致控制岩样最终的含水饱和度。由于恒湿环境中水蒸气的逸度是恒定的,当环境中水蒸气的逸度与岩样中组分水的逸度不同时,外界恒湿环境中的水蒸气与岩样中组分水形成逸度差,当环境中水蒸气逸度小于岩样中组分水的逸度时,岩样中组分水渗出;反之,则水渗入岩样,最终岩样中组分水的逸度达到与外界恒湿环境相同的状态,制得相应含水饱和度的岩样。岩样是放置在负压环境中制备的,在负压环境中岩样孔隙中的空气减少,水蒸气在岩样中的渗透加快,从而缩短了岩样达到稳定的时间。根据气液平衡原理,岩样稳定时,岩样各个部分组分水的逸度相同,因此,制得的岩样含水分布均匀。     

地球化学的理论体系与方法论

本文根据地球化学作用与时-空结构辩证统一的观点提出地球化学的理论体系与方法论,认为地球化学体系应由地球化学系统的物质、地球化学作用、地球化学过程和地球化学场等四大部分所构成,其中以地球化学系统的物质为基础,而地球化学作用居于核心地位。地球化学作用与时-空结构的统一性应该作为一切地学研究的指导思想。作者指出,必须用系统思想和系统科学研究地球化学系统,应用不可逆过程热力学中的“耗散结构”（dissipativestructures）理论研究地球化学作用与时-空结构的内在联系。     

二元系主要相图类型的热力学推导

本文介绍了混合 Gibbs 自由能-组成曲线的基本原理,并在此基础上,推导了二元低共熔系、分解熔融系、固态无限混溶系、具低共熔点的固态有限混熔系,液态有限混熔系相图以及二元系的旋节线和旋节点。     

短期降水预报的动力学与热力学

提出了当前短时和短期降水预报中需待解决的3个问题。由这些问题引发了如何把动力学与热力学相结合，如何把大量的观测和模式资料应用于短期无间隙预报的思考。最后给出了一个短期大暴雨预报的应用实例。     

Thermodynamics of hydration of Na- and K-clinoptilolite to 300 °C

The hydration state of Na- and K-exchanged clinoptilolite from Castle Creek (Idaho, U.S.A.) has been measured by a pressure titration method to 300 °C and P _H2O<30 bars. The water content of clinoptilolite can be predicted as a function of water activity and temperature with the equation: a _H2O = [exp[[−ΔH _h ^∘/nRT] + [ΔS _h ^∘/nR] − 1/nRT· [W₁ X _h + W₂ X _{h 2}]− ln(X _a/X _h)]]⁻¹ where T is degrees in Kelvin, ΔH _h ^∘ is the standard molal enthalpy of hydration, ΔS _h ^∘ is the entropy of hydration, X _h and X _a are, respectively, the mole fractions of the hydrous and anhydrous components of the solid solution, W ₁ and W ₂ are interaction parameters, n is the maximum number of moles of H₂O per formula unit (based on 12 oxygens), and R is the gas constant. This equation can be used to locate clinoptilolite-H₂O isohydrons in a _H2O-T space below the liquid-vapor equilibrium curve of water. The standard molal Gibbs free energy of hydration is −47.62 ± 5.52 kJ/mol H₂O and −5.40 ± 2.71 kJ/mol H₂O for the Na- and K-clinoptilolite, respectively. These standard-state thermodynamic properties of clinoptilolite hydration are in good agreement with previous data at low H₂O pressures. The experiments indicate that clinoptilolite progressively dehydrates with increasing temperature at pressures along the liquid-vapor equilibrium curve. Kinetic data above 150 °C show that clinoptilolite dehydration and hydration reactions are fast and reversible and that steady-state hydration states are attained in minutes. Received: 19 June 1998 / Revision, accepted 14 December 1998     

Au-Sb association and fractionation in micro-disseminated gold deposits, southwestern Guizhou—geochemistry and thermodynamics

The dual geochemical character of paragenesis and fractionation between gold, arsenic and antimony in micro-disseminated gold deposits in southwestern Guizhou is discussed in terms of spatial distribution of independent deposits, lateral and vertical enrichment, mineralization stage and factor and correlation analyses. Thermodynamic calculations of solubility and speciation of gold and antimony minerals indicate that gold is transported in hydrothermal solution as Au(HS)^- ₂ and antimony is mainly as Sb (OH) ₃ ⁰ although HSb₂S₄ may be of increasing importance in acid environment at low temperatures during the late stage of mineralization. Changes in physicochemical conditions hold the key to the association and fractionation between gold and antimony. Gold and antimony response differently to physicochemical variations because they are distinct from each other in soluble speciation and mineral solubility, leading to precipitation at different times and localities during hydrothermal evolution.     

Self-organized genesis of Lunijianlaite and its apparent single-crystal

From the structure of layer stacking of Lunijianlaite and its host and theory of nonequilibrium thermodynamics, a nonlinear dynamical model named “Shenkuoator” has been presented under the condition of nonequilibrium. The numerical results have been successfully used to explain the self-organized ordering phenomenon at two levels in the apparent single-crystal. Hence, the latter has been confirmed as crystallization product of the supersaturated silicate solution, whose chemical composition is between that of cookeite and pyrophyllite, under the conditions of nonequilibrium and nonlinearity.