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1.
2002年山东省大气污染造成的经济损失估算   总被引:6,自引:0,他引:6       下载免费PDF全文
在对2002年山东省大气污染资料调查和统计的基础上,应用环境经济学的原理与方法(人力资本法、市场价值法、机会成本法、资产价值法等),对大气污染造成的经济损失进行了估算,结果表明2002年山东省大气污染经济损失约为126.379亿,约为当年山东省GDP的1.2%。  相似文献   

2.
综合电法在采空区探测中的应用   总被引:6,自引:0,他引:6  
简要介绍了所测矿区的地质概况和地电特征,分析了中间梯度法和瞬变电磁法的工作原理及各自的优势,通过实例说明了综合电法(直流电测深、中间梯度和瞬变电磁法相结合)在探测采空区中的应用效果良好。  相似文献   

3.
以钛酸丁酯为前驱体,无水乙醇为溶剂,采用溶胶-凝胶法和浸渍法制备了不同Ce、Nd掺杂量的TiO2/C复合材料光催化剂。通过X射线衍射(XRD)、扫描电子显微镜(SEM)、傅里叶变换红外光谱(FT-IR)、固体粉末紫外漫反射等对样品进行了表征,并在紫外光照射下,以亚甲基蓝(MB)为降解物,研究了不同Ce、Nd含量样品的光催化性能。  相似文献   

4.
含氰废水处理方法评价   总被引:8,自引:0,他引:8  
氰化物是指化合物分子中含有氰基(-CN)的物质,属于剧毒物。含氰废水处理方法很多,处理方法的选择应根据具体情况而定,本文主要介绍了过氧化氢法、二氧化硫一空气法、生物处理法、氯氧化法。处理含氰废水的处理过程。  相似文献   

5.
三维摩擦接触问题算法精度和收敛性研究   总被引:16,自引:0,他引:16  
回顾了摩擦接触问题的现有解法,包括Lagrange乘子法、惩罚函数法、增广Lagrangian乘子法,线性互补模型及互补类非线性方程组方法等,尤其是近期关于非线性方程组方法的系列研究结果:(1)三维弹性摩擦接触问题互补类非线性方程组的光滑化解法;(2)将其推广为非光滑解法;(3)三维弹塑性摩擦接触问题增量方程和算法,非线性方程组方法解法基于严格的数学理论基础,严格地满足接触条件,并用随机数产生的接触柔度矩阵证实了算法的收敛性,由于每个接触点对的未知数只有3个,不合任何人工变量,同时,算法有局部二次收敛率且计算效率很高。为了考察以增广拉格朗日法为代表的工程中流行算法的精度和收敛性,设计了一个典型的弹性摩擦接触问题算例,证实了通用程序ANSYS的增广拉格朗日法是近似的并且不能保证收敛。  相似文献   

6.
在工科高等数学教材中,关于二阶常系数非齐次线性微分方程只给出了自由项为两种特殊形式(即f(x)=e^λxPm(x)或f(x)=e^ax[Pl(x)cosβx Pn(x)sinβx])时的解法,本文就自由项为一般的一个连续函数f(x),采用常数变异法,并利用分部积分,推出了一般二阶常系数非齐次线性微分方程的通解公式。常数变异法较之待定系数法,在特解的假设过程中避免了对f(x)形式的讨论,因而更具一般性。  相似文献   

7.
采用行波法和近年来发展的齐次平衡法求解一类运用广泛的Sine-Gordon方程,获得形如tanh(x-vt)的扭结孤子解。针对齐次平衡法出现解遗漏的情况,提出了直接求解法。  相似文献   

8.
本文通过聚合酶链式反应(PCR法)、斑点杂交法(Dot blot)以及酶联免疫法(ELISA法)对55例疑有乙型肝炎的病人进行了检测。结果显示:在乙型肝炎病原基因(HBVDNA)检测上,PCR法的敏感性显著高于Dof blot法(X~2=4.251 P<0.05)。乙型肝炎病原基因诊断可以直接检测血液中乙型肝炎病毒(HBV)的存在情况,并能检出低水平的病毒复制。从而弥补了ELISA不能完全反映HBV的存在状态以及敏感性的不足。据此,可以认为,乙型肝炎的病原检测应用时采用PCR法与ELISA为宜。  相似文献   

9.
以DO作为SBR法控制参数的研究   总被引:1,自引:0,他引:1  
序批式活性污泥法(Sequencing Batch Reactor简称SBR法)处理污水是一个好氧过程,溶解氧(DO)是重要的指示性参数。它不仅影响处理效果,还关系到运行费用。本文用在线检测的DO作为SBR的控制参数,通过控制风机的频率的方法,调节曝气量,控制溶解氧,在保证出水水质的同时减少了运行费用。  相似文献   

10.
间接酶联检测法浅谈   总被引:3,自引:0,他引:3  
比较了间接酶联检测法和双抗体夹心法检测烟草花叶病毒(TMV)的结果,检测提纯的病毒和叶片榨汁中的病毒,间接酶联检测法的灵敏度都比夹心法高.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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