Web-based Rare Earth Compound Database System Research And Development,

The rare earth (RE) is widely applied in many fields of national economy, such as metallurgy, petroleum chemical engineering, glass & ceramics, atomic energy, function material and textile industry, medicine, agriculture & herd industry and so on because it has a series of special property and function. The resources of RE is extremely abundant in our country and has many traits, including in great reserves, wide distribution, multi- minerals, multi- types and high value etc. The reserves accounts for over 70% all of the world according to already find. All these are advantaged for developing RE industry in our country.The study, analysis and simulation of the rare earth & its compound by using Internet & Web technology have become an important task. Now there are many parameters about the thermodynamics, physical properties and structure etc, but they exist everywhere and are not gathered. The purpose of this dissertation is to study and develop the Web RE DB system based on multi-tiers system architecture and further to study and simulated computation for RE compound. China has the richest RE resources and is on the frontier for the application study & extraction of RE in the world. Now there is no study about this kind of DB on domestic & abroad after referring to a lot of the scientific literatures. Moreover there are less data of RE in the related databases that had been developed. So this dissertation's study has not only important theoretical value, but also practical value.The functions & related computation model are essential for the Web RE DB system. This system is designed as the six sub-databases: thermodynamic DB, physics property DB, structure DB, graphic DB(phase graphic, predominate graphic, reaction balance graphic), technics parameter DB and mineral DB. The functions & contents of thermodynamic DB, physics property DB and structure DB are studied. In the thermodynamic DB, the primary contents and function are selected as followed: Based on the phase of compound, noting and calculating thermodynamic data individually; Heat capacity is expressed temperature function; Molar formation enthalpy, standard entropy of each phase will be unified to 298.15K, and simplified the calculate formula of enthalpy and entropy; Adopted nonstandard calculated data of Gibbs function to simplified the calculation process; Present the correlated calculation formula and process logic. To implement these functions of DB, some assistance programs of the thermodynamic DB software also are studied and developed, such as programs of chemical equation balancing and element analysis of a compound's molecular formula because all these are essential for the complete thermodynamics software. Moreover, this paper discusses the selection of international units, expression of calculation results, format of molecular formulae, and other pertinent topics.Two key technologies (the middleware and Web technology) are studied in the dissertation. Based on it, this dissertation researches the system architecture of Web RE DB. The improved multi-tiers C/S model of Web RE DB is put forward according to its application characteristic by analyzing, comparing and improving the defects in the two-tier & three-tier C/S architecture. This multi-tier C/S model can avoid the problem of load and can separate the application server and the DB server. This multi-tier architecture is vital for the development of Web RE DB system.The data access is very key technology to the Web RE DB system. The dissertation studies and designs the Web RE DB system based on ADO.NET, the connection & access mechanism in DB and the mechanism of connection manager by analyzing and comparing CGI,API,ODBC,JDBC,ADO and ADO.NET etc. The DB connection manager is designed to implement data access.Another technology is studied in the dissertation: SOAP technology, in order to share the data among the different DB and communicate on Internet. The Web RE DB model based on SOAP is put forward after analyzing its specification & rules.The dissertation also studies some other problems that have to be studied in the development of the Web RE DB, including in the tight coupling & loose coupling model, the relation DB structure, the parameters in DB, the permission configuration and the software development etc.In the end, the dissertation introduces detailedly function implement of the system, concrete contents and the part calculation process online. The traits, such as multi-function, friendly interface between user and system, easy operation etc, are displayed by using the real data & calculation result. It has been showed that the system has not only the function of database management, but also the function of calculation using the data in the database and making graph according to computation result. All these are theoretical base for study and analysisi.