成都市凤凰山公园土壤重金属污染环境监测研究

随着现代工业的发展,环境污染日益加剧,土壤重金属污染日趋严重.以具体项目土壤重金属污染环境监测为例,通过监测因子数据分析,对该区域土壤重金属污染情况做出评价,以体现环境监测对土壤重金属污染进行评价、分析、指导方面的积极作用.     

矿区土壤重金属污染修复技术研究进展

本文分析了土壤重金属污染较严重的几种典型矿区的污染来源及污染现状,发现金属矿区的重金属污染较煤矿区污染更为严重,往往为多金属复合污染,修复较为困难,土壤重金属污染的治理已刻不容缓。并重点评述了应用于矿区重金属污染土壤主要修复技术的国内外研究现状,了解到土壤淋洗技术、土壤固定化技术、植物修复技术和多种修复技术相结合的复合修复技术为现今国内外研究的重点。在此基础上指出了我国在今后的矿区土壤重金属修复方向的研究重点为高效环保的土壤添加剂的研究,超累积植物或大生物量重金属富集植物的筛选和培育以及土壤修复技术的高效联合使用。     

蔬菜-土壤系统重金属污染现状及防治措施

该文阐述了蔬菜-土壤系统重金属的污染现状,总结了当前蔬菜-土壤系统重金属污染防治的主要措施,最后提出了蔬菜-土壤系统重金属污染方面今后的若干研究方向,旨在为蔬菜-土壤系统重金属污染方面的进一步深入研究提供借鉴。     

基于主成分综合模型的矿区农田重金属污染评价

文章尝试利用变量聚类分析方法对矿区附近农田土壤重金属污染的主要污染物进行辨识,并采用 综合主成分分析法对矿区附近农田土壤重金属污染情况进行评价和分级。分析结果表明：利用变量聚类分 析法可以有效地辨识矿区附近农田土壤重金属污染中的主要成分;运用综合主成分分析法,确定样本的综合 主成分,并对其排序和聚类,可以有效揭示矿区附近农田土壤重金属污染物的数据结构、相互关系和不同样 品点的污染程度。采用主成分分析方法对矿区附近农田土壤重金属污染情况的评价结果,反映了矿区主要 重金属污染物的影响,同时又定量化了土壤复合重金属污染研究。辨识和评价结果可为矿区附近农田土壤 重金属污染治理对策的提出和重点治理区域的确定提供参考和指导。     

论述国内土壤重金属污染治理的主要措施

近年来,重金属污染物通过多种渠道渗入到土壤中,造成土壤重金属污染,影响农作物生长,危害人类健康,甚至造成水环境污染正因如此,全世界各个国家已经将土壤重金属污染作为一项重要治理工程。该文主要对我国土壤重金属污染治理的主要措施进行论述。     

天津郊区菜田土壤重金属污染环境质量评价

天津市土壤重金属污染已经形成环境问题，本文利用基于改进AHP法确定权重的加权平均评价方法对天津郊区菜田土壤受重金属污染现状进行了评价，结果发现宁河、静海、宝坻、蓟县和武青菜田土壤的重金属污染均为2级，属于尚清洁水平，东丽、西青和津南菜田土壤的重金属污染均为3级，属于轻度污染水平，北辰菜田土壤的重金属污染为4级，属于中度污染水平．由此说明天津市东丽、西青、津南和北辰等区的土壤重金属污染已经开始影响人类健康，因此应及时给予修复，以保证土壤的可持续利用．     

铅锌矿区土壤重金属含量的调查与评价

研究贵州SS、SQ典型铅锌矿区土壤的环境质量,在SS、SQ铅锌矿区采集土壤样品共15个,利用F-640、AA800等仪器测其土壤中7种重金属元素的含量,采用单因子污染指数法和N.L.Nemerow综合污染指数法对研究区域重金属污染进行分析,结果表明,矿区土壤中重金属污染程度有较大差异,Cu、As、Cr等3种重金属元素无或轻污染;Cd、Zn、Hg、Pb等4种重金属元素对该区土壤环境已造成污染;SS、SQ土壤中重金属综合污染相当严重。     

白银市郊区重金属复合污染对土壤酶活性的影响

对白银市城郊地区土壤重金属质量分数和酶活性的测定及分析结果表明:白银市东大沟周边土壤都受到了不同程度的Ni,Pb,Cu,Zn,Cd污染,上中游污染较为严重,土壤酶活性随着重金属污染程度的加剧呈降低趋势.相关分析表明,单一的脲酶、蔗糖酶以及过氧化氢酶活性对重金属污染较为敏感,可以作为指示灰钙土分布区土壤重金属污染程度的酶活性指标.根据主成分分析法和系统聚类分析,建立了总体酶活性指标作为表示污染土壤酶活性信息系统的综合指标,表明了总体酶活性可以表征该区土壤的重金属污染状况.     

土壤重金属的污染与治理进展研究

土壤重金属是土壤环境污染最主要的一个方面.介绍了重金属污染的特点和危害机理,并针对污染途径提出了"减源""截流"和"修复"治理措施,控制流入环境中的重金属的绝对值;重点介绍了土壤重金属污染修复的各种方法.     

土壤重金属污染治理与修复方法研究进展

土壤重金属污染的治理和修复的基本原理是将重金属清除或改变其在土壤中的存在形态,降低迁移性和生物可利用性。根据土壤的性质和重金属在土壤中的赋存形态不同,目前重金属污染土壤治理和修复方法可分为工程物理化学法、土壤农化调控法和生物学修复法。通过对重金属污染治理与修复方法的综述,得出了各种方法的优缺点和适用范围,并对重金属治理的方法进行了展望。     

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-