饮用水遗传毒性评价方法建立和应用

建立了一组多效应终点、多层次的饮用水遗传毒性测试体系,并用于盐城某水厂饮用水处理工艺的评价.采用Ames试验菌株TA98和TA100检测水样浓集物致突变效应,分别利用人外周血淋巴细胞微核试验和彗星试验检测染色体结构损伤和DNA链断裂程度.Ames试验结果显示,水样浓集物在0.5~2.0 L/皿的浓度范围内未出现致突变性.微核试验中原水、砂滤水和出厂水均表现出较强的致染色体畸变作用,0.125 L的剂量即可引起淋巴细胞微核细胞率的升高,经过臭氧-生物活性炭处理后各剂量均与对照无差异.彗星试验结果显示,各水样均在不同剂量下对淋巴细胞DNA造成损伤,原水、出厂水、砂滤水、生物活性炭(BAC)水的作用剂量分别为0.25,0.25,0.50和1.00 L,损伤程度从大到小依次为原水、出厂水、砂滤水、BAC水.     

黄浦江原水的生产性试验研究

采用杨树浦水厂新建的组合工艺(预臭氧氧化→高密度澄清池→砂滤→后臭氧氧化→生物活性炭)处理有机物和氨氮含量较高的黄浦江原水,研究水力负荷对该工艺处理黄浦江原水效果的影响,并分析该工艺在最佳水力负荷下长期运行时处理效果的变化情况.结果表明:该工艺能够长期稳定运行,出水水质达到国家饮用水标准,适宜作为微污染水源水的有效处理工艺;在设计水力负荷范围内,适当增加处理水量可更好地发挥该工艺的效用,且对有机污染物的去除率不会有明显降低;杨树浦水厂调试运转中该工艺流程的最佳水力负荷定为1 200m3/h.     

水网二次污染的原因及解决方法

符合饮用水水质标准的出厂水,经管网输送到用户后,经常会受到二次污染.文章从内因和外因两方面分析了造成水网二次污染的原因,并对此提出了改善管网水质的多项措施和方法.     

氯胺消毒在给水中的应用

液氯消毒是目前应用较广泛的饮用水消毒剂,人们发现经过液氯消毒过的水中含有三卤甲烷、卤乙酸及其他大量的饮用水消毒副产物.三卤甲烷是一种环境激素物质可以致癌致突变.经氯化消毒的饮用水中还含有一定量的有机溴代物和碘代物,这些物质给人们健康造成威胁.相对液氯消毒、氯胺消毒是利用氯胺在水中缓慢释放的次氯酸进行消毒的,这样可以大大减少三卤甲烷和其他消毒副产物的生成量,消毒效果好、持续时间长.出厂水和管网水的微生物指标可低于国家饮用水卫生规范的最高限制.采用氯胺消毒能够很好地控制氯化消毒副产物的生成量.     

生活饮用水的细菌检测与分析

目的了解某水厂生活饮用水的细菌学指标情况及其变化规律,利于对水体环境进行治理,以控制水源性疾病的传播。方法选取2018年1月至3月随机抽取的该厂水样共105份水样作为检测样本,共包括45份出厂水水样、12份源水水样以及48份管网水水样。对所选水样样本进行细菌检测与分析,检测方法为传统饮用水微生物检测法。分析所选样品的细菌学情况。结果对所选水样进行细菌性学检测,结果显示该厂的出厂水、管网水、源水水样细菌总数以及总大肠菌群合格率分别为64.4%、57.8%,33.3%、22.2%,33.3%、25%,其中出厂水合格率尚可,但管网水及源水的合格率较低。结论该厂的管网水及源水的水质控制欠佳,需要加强监测,避免影响出厂水的水质状况,进而影响居民身体健康。     

上海河流沉积物的有机提取物对3种细胞的毒性效应

河流沉积物是众多有机污染物的最终储存库.采用索氏抽提法提取出黄浦江及支流苏州河沉积物中的有机污染物,用CCK-8法检测沉积物中的有机提取物对正常人肝细胞L02、人肝癌细胞HepG2以及人乳腺癌细胞MCF-7的细胞增殖毒性,综合评价沉积物中有机污染物的综合毒性效应,进而比较沉积物有机提取物对这3种细胞增殖毒性的差异及两条河流沉积物受有机污染物污染的情况差异.结果表明,黄浦江与苏州河沉积物有机提取物对MCF-7细胞和L02及HepG2细胞表现出不同的毒性效应,黄浦江与苏州河沉积物中的大部分样品对L02和HepG2表现出一定的促增殖效应或没有影响;对MCF-7细胞,除个别样品外,大部分样品表现出细胞增殖毒性效应,并且呈剂量效应及时间效应依赖关系,其毒性大小与采样的位置存在很大关联,这说明黄浦江及苏州河沉积物有机提取物一定程度上受到了有机污染物的污染.另外,两条河流对L02和HepG2的促增殖效应和对MCF-7细胞增殖的毒性效应相当,说明两条河流受有机污染物的污染强度接近及污染物类型相似.     

膜处理工艺对饮用水生物稳定性的影响

围绕饮用水的生物稳定性．讨论了微滤(MF)、超滤(UF)、纳滤(NF)和反渗透(RO)等膜处理工艺对饮用水中有机污染物的去除效果，指出这几种膜处理工艺对饮用水生物稳定性的影响．经微滤和超滤膜处理后的出水不具备生物稳定性，而经反渗透和纳滤膜处理后的出水有较好的生物稳定性。     

水样脱氯检测氨氮相关问题的探讨

2012年《生活饮用水卫生标准》（GB 5749-2006）开始全面实施后,氨氮指标将由参考指标变成强制指标。由于常规工艺对氨氮的去除作用不是很明显,因此在无法改变目前的氯胺消毒方式和管网状况的情况下,在水源水氨氮接近超标或略微超标的情况下,要保证出厂水氨氮达标,同时保证出厂水余氯量,必须做好氨氮的实时检测和精确控制氨、氯的投加量。     

传统自来水处理工艺对农药和兽药的削减效率

地表水中农药兽药复合污染导致的饮用水源水质安全问题,已经成为政府、民众和科学家关注的焦点,而现行自来水处理工艺对多种有机污染物的削减效率,则是新的研究热点.以280种农药和100种兽药为目标物,应用本课题组建立的液液萃取和固相萃取前处理方法及气相色谱/液相色谱-串联质谱检测方法,分析了2015年12月采自某市两个自来水厂的源水、沉后水、滤后水及消毒后出厂水中的目标污染物,分析了检出和削减情况.结果发现:水样中检出总计28种农药和8种兽药;源水和消毒后出厂水中,单一农药的检出质量浓度分别为0.212~87.85 ng/L和ND(未检出)~43.27 ng/L,单一兽药的检出质量浓度分别为4.742~54.16 ng/L和ND~40.66 ng/L.经传统自来水工艺各环节处理后,部分农药兽药的质量浓度并非逐级递减;在过滤和消毒环节存在质量浓度回升的现象,可见传统自来水处理工艺无法彻底消除农药兽药.     

供水管网二次污染的因素及改善措施

管网安全供水需要同时满足用户在水质、水量覆水压三方面的要求．符合水质标准的出厂水，经管网输送给用户后．水质常常会发生二次污染．本文从管网管材、管网水自身物化反应、管网附属设施、盲肠段、二次供水设施、管道施工等方面分析了造成供水管网二次污染的原因，并针对这些因素提出了改善管网水质的多项措施和方法．     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

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