浅谈海水淡化的发展

本文介绍了海水淡化主要工艺的发展。在我国当前的水环境下,水资源紧缺问题日益突出,海水淡化技术的发展愈显紧迫。海水淡化方法有很多种,本文主要介绍多级闪蒸法、反渗透法等,并介绍国内外研究与应用的一些新进展。     

海水淡化工艺的发展

本文介绍了海水淡化工艺的发展。在我国当前的水环境下,水资源紧缺问题日益突出,海水淡化技术的发展愈显紧迫。海水淡化方法有很多种,本文主要介绍多级闪蒸法、反渗透法等,并介绍国内外研究与应用的一些新进展。     

多维度海水淡化技术比较及产业前瞻

对比了国内外海水淡化技术应用的方法、规模、差距,并介绍了海水淡化技术的最新进展.比较了多级闪蒸、多效蒸馏、反渗透三种主流淡化技术的性能差异与适用条件,为海水淡化技术的选型提供了参考.并从实际需求与国家政策层面剖析了我国海水淡化产业的发展前景及巨大潜力.     

多级闪蒸海水淡化系统的改进研究

针对供热机组进行电水联产的参数特点,综合多级闪蒸海水淡化技术(MSF)和低温多效蒸馏海水淡化技术(LT-MED)的优点,提出了一种多级闪蒸海水淡化的改进系统(MSF-E),其改进方法是利用供热汽轮机0.12~0.25 MPa的供热蒸汽作为热源,将各级闪蒸室中闪蒸出的二次蒸汽的一部分引到下一级闪蒸室中用来加热循环盐水,同时以供热机组凝汽器的循环海水代替原海水作为多级闪蒸系统的补充水,并建立了MSF-E系统性能计算数学模型,分析了参数变化对MSF-E系统性能的影响规律.研究与计算结果表明,与现有MSF装置进行对比,在引出份额达到理论最大值0.743时,造水比可提高42.6%,各级闪蒸室中盐水的质量分数平均下降22.1%,可以更好地发挥供热机组进行电水联产的优越性,为MSF-E系统的实际应用奠定了理论基础.     

中国沿海岛屿的淡水资源及几种可行的海水淡化方案

文中介绍了中国沿海岛屿的淡水资源状况;针对海岛的地理、能源条件,分析和评价了多级蒸发(MED)、多级闪蒸(MSF)、压汽蒸镏(VC)、电渗析(ED)、反渗透(RO)以及其它混合形式的海水淡化方案的特点与应用的可行性.从而为开展海岛海水淡化科研、产品开发和投资决策提供参考.     

沿海电厂海水淡化技术应用现状

海水淡化实际上就是降低海水的盐度,饮用水的盐度为500mg/L,海水淡化就是把海水的盐度降低到500mg/L。目前,我国现有的沿海电厂海水淡化技术有以下几种:一是蒸馏法,二是膜法。其中,蒸馏法包括:一是多级闪蒸法,二是多效蒸馏法,三是蒸汽蒸馏法。膜法包括:一是电渗析法,二是反渗透法。技术人员需要结合实际情况选择沿海电厂海水淡化技术,以实现海水淡化目标。     

水电联产低温多效蒸发海水淡化系统优化研究

在对带有冷凝水闪蒸和海水预热的低温多效蒸发海水淡化系统进行物料和热量衡算的基础上,建立了相应海水淡化系统并叉流流程下水电联产系统优化的数学模型.该模型以单位产量淡水成本最小为优化目标,利用Matlab工具箱编制了求解程序,对水电联产系统数学优化模型进行了求解,分析了效数、加热蒸汽流量和系统规模对单位产量淡水成本的影响,并将水电联产优化设计、水电联产等温差设计和无水电联产等温差设计3种方案下的单位产量淡水成本进行了比较.计算结果表明:参数相同情况下,水电联产优化设计和无水电联产等温差设计相比,最大可节约淡水成本87.54%.水电联产低温多效蒸发是降低海水淡化成本的有效途径.     

宁德核电站海水淡化处理技术研究

本文以该海水淡化工程为案例,介绍了我公司膜法海水淡化工艺中的多级系统,如海水取水系统、预处理系统、予脱盐系统(SWRO)、二级除盐系统(RO2nd)等,并对宁德核电工程的制水成本经济进行了分析。     

核能海水淡化

我国被联合国认定为13个最贫水的国家之一,核能海水淡化是应对将来可能出现的全国大范围水危机的重要途径。在竞争性方面,核能海水淡化在环保,缓解交通运输等方面,有很强的竞争能力;在经济性方面,其成本仍比国内水价高出2.8到9.97倍。在环保、缓解交通运输负担等方面,其竞争能力强。     

浅谈反渗透膜法工艺在核电站海水淡化中的应用

本文对海水淡化技术的工艺进行了分析与讨论,以辽宁红沿河核电站的海水淡化工艺为例,探讨了反渗透膜法水处理技术在海水淡化中的应用,为后续海水淡化技术在核电项目领域的应用提出了建议。     

Markedness and its Interpretation in Language Use

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.     

Features of Women's language

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-