Reliability Estimations of Control Systems Effected by Several Interference Sources

In order to establish the sufficient and necessary condition that arbitrarily reliable systems can not be constructed with function elements under interference sources, it is very important to expand set of interference sources with the above property. In this paper, the models of two types of interference sources are raised respectively: interference source possessing real input vectors and constant reliable interference source. We study the reliability of the systems effected by the interference sources, and the lower bound of the reliability is presented. The results show that it is impossible that arbitrarily reliable systems can not be constructed with the elements effected by above interference sources.     

670矿床多期成矿作用特征及控矿因素研究

670矿床是典型的火山岩型富铀矿床,具有多期成矿特征。主要成矿期可分为两期。早成矿期矿化主要和红化有关,成矿溶液主要由大气降水组成,其中铀主要以UO_2(CO_3)_2~(2-)形式存在(99.6%),矿化温度133℃(平均值),成矿时代131Ma;晚成矿期成矿溶液主要为岩浆水,铀以UO_2(CO_3)~(2-)(89.4%)和UO_2(SO_4)_2~(2-)(9.2%)形式存在,矿化温度239℃(平均值),成矿时代为106.3±2.1Ma.670富铀矿床的形成是两期成矿作用叠加、多种因素复合作用的结果。     

The range of life in amber: significance and implications in DNA studies

A survey of the major fossiliferous amber deposits is provided, including ages and various categories of life forms reported from each. The frequence of occurrence of the major groups of plants and animals in these amber deposits is also given. Thus far, DNA from four insect and one plant species has been extracted from amber fossils. In the case of the stingless bee in Dominican amber, evidence of reproducibility is provided, since two independent laboratories isolated DNA from six or more different specimens of the same insect.Amber sources for DNA studies are listed together with their advantages and disadvantages. The important points are the availability of desired pieces, the proper identification of the fossil, verification of the amber deposit, the cost involved, and the feasibility of causing damage to the specimen. The availability of several types of amber (Mexican, Dominican, Baltic, Chinese, Canadian, Siberian and Lebanese) at four major sources (academic collections, commercial dealers, private collections and amber mines) is discussed. The scientific implications of obtaining DNA from amber inclusions are presented.     

污染源对大气环境质量影响模拟(Ⅰ)

本文介绍SXVEQAS(山西大学环境质量评价系统)中污染源对大气环境质量影响模拟的数学方法。全文分为两大部分,第一部分为单污染源影响模拟方法,主要介绍长期平均浓度等浓度曲线与污染区划分的计算方法,并以岳南矿为实例说明。下文将介绍第二部分,介绍多污染源影响模拟的一些数学方法。它主要研究使用网格法进行对大气污染形势模拟、大气污染预报、等浓度曲线和污染区域划分计算的数学方法,这是区域性环境质量评价与环境规划中急待解决的关键问题。     

试论中国古代固有民法的开放性体系

近年来法律史研究中对正律以外的大量史料的考证足以说明:既然中国古代曾有辉煌的国际和国内贸易是不争的事实,且调整这些社会关系的大量的行为规则和裁判规则的存在亦不容置疑,那么,只要转换思路,从实质意义上的民法渊源的角度来看问题,就不但可以发现中国古代固有民法的实在体系,而且能够概括出其特有的调整模式。这无疑对目前我国民法典的编纂同样具有重要的现实意义。     

景德镇市生态旅游开发的初步构想

景德镇市生态旅游资源丰富,其优势区域在浮梁县,瑶里尤为突出,拥有瓷之源,茶之乡,林之海的美誉。另外,浮梁县水上生态旅游资源也值得大力开发。     

硫化纳米零价铁去除水溶液中铀的机理

研究了铀溶液初始pH、HCO－₃质量浓度和硫化纳米零价铁(sulfidized nano-scale zerovalent iron,SnZVI)投加量对SnZVI去除铀的动力学过程的影响,并通过SEM、XRD和XPS阐明SnZVI去除铀的机理。球形SnZVI颗粒直径为100~200 nm,比表面积为43.5 m²/g。SnZVI颗粒中含有Fe和FeS,且Fe(0)和Fe(Ⅱ)含量超过80%。SnZVI去除铀的动力学过程符合准一级动力学模型。增加SnZVI投加量,反应后溶液中铀质量浓度低于0.05 mg/L,但是pH升高及HCO－₃质量浓度增加导致SnZVI去除铀的速率降低。SnZVI去除铀的负荷达到2 452.92 mg/g,且反应后颗粒中约85%的铀为U(IV)和U(V)。研究结果表明,SnZVI可通过表面官能团的吸附作用及Fe(0)的还原作用快速分离水溶液中的铀。     

某铀矿细菌菌群柱浸过程中的硫强化作用及其机理分析

评估了由Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans和Leptospirillum ferriphilum组成的混合菌群在柱式反应器中浸出某复杂铀矿的硫强化作用及其可行性。在77 d细菌柱浸过程中,硫强化(8 g/kg)后,铀的浸出率达到了约83.61%,与对照组相比,增加了10%。利用扫描电镜和X射线荧光光谱仪对矿渣进行了表征,结果表明硫强化后的矿渣表面有细菌侵蚀的痕迹且孔隙度增大。细菌群落分析表明,硫强化后浸出液中的优势种群从Leptospirillum ferriphilum转变为Acidithiobacillus ferrooxidans,且Leptospirillum ferriphilum在下层矿石表面占比从强化前的4.3%增加到了40.74%,和Acidithiobacillus thiooxidans保持了较好的平衡。此外,动力学分析表明,铀矿细菌柱浸动力学模型更遵循了通过中间产物层控制的内部扩散模式,且硫强化能够增强铀的浸出动力学。最后,建立了一个与细菌群落和化学反应相关联的硫强化生物浸铀的机制模型。     

DENISON经济增长因素分析的模型化与经济增长方式

丹尼森的经济增长因素分析是对经济增长理论的重要贡献, 但他没有提供模型化方法。本文提出了对丹尼森的经济增长因素分析进行定量化模型化的方法, 并利用这种模型化方法讨论了经济增长来源与经济增长方式的问题。