明代嘉万间盐课银收支与盐法体制变迁

财政是国家的命脉,盐利是财政收入的重要来源。以运司的盐课银收支为对象,分析明代盐法在嘉万间从开中法向纲盐法变革中缓慢而深刻的变迁过程。嘉靖、万历间,户部的盐课收入既有正盐银,也有余盐银,这说明"正盐纳粮输边,余盐纳银解部"的说法值得商榷。嘉万间,盐课银是户部银库最大宗收入,但并非明初以来制度规定的收入形态。其出现和拓展,表明盐法体制有着重大调整。这表现在:盐商中的边商向运司领取价银;州县代盐场缴纳灶课银;本来没有制度性盐利收入的皇帝,加入盐课银的分割行列。从国家白银财政收入的角度看,内商因为向户部银库缴纳了大量余盐银,比边商对财政作用更大。这意味着,在开中法没落的情况下,户部将日益重视其和内商的关系,从而为万历末户部强制内商占窝的纲盐法改革埋下伏笔。

明代中后期的双轨盐法体制

本文以太仓库为切入点,从开中制与太仓库的收入、余盐与太仓库的收入两方面对明代盐法体制的演变进行梳理,并得出如下结论:嘉靖时期,在既要维持开中祖制、又要解决开中制无法有效满足边镇现实财政需求的情况下,正盐开中输边、余盐纳银解送户部太仓库的双轨盐法体制就此形成;其后直至崇祯,虽时有反复,但它一直是明代中后期盐法的主流体制。

Two-dimensional Modeling of a Salt-gradient Solar Pond with Wall Shading Effect and Thermo-physical Properties Dependent on Temperature and Concentration

In this paper,the behavior of a salt-gradient solar pond with the square cross-section has been studied experimentally and numerically.A small-scale solar pond were designed and built to provide quantitative data.A two-dimensional,transient heat and mass transfer model has been solved numerically by using finite-control-volume method.In this study,all the thermo-physical properties are variable as the function of temperature and salt concentration.Numerical results as obtained for the experimental pond have been satisfactorily compared and validated against measured data.Furthermore,the wall shading effect has been elaborated to improve the agreement between two sets of results.The temperature of the storage zone is predicted well by the model.It also can be observed that the initial concentration profile is preserved with time.The stability of the pond in time has been investigated in order to distinguish the critical zones.Finally,the application of an energy analysis gives an efficiency of about 12%for the pond.