超滤膜去除地下水中硝基苯的试验研究

为解决持久性有机污染物对地下水造成的污染，以硝基苯为研究对象，考察了超滤膜对硝基苯的去除效果及影响因素。试验结果表明，当进水硝基苯浓度为85肛μg/L，超滤膜可以连续工作68h，出水小于17μg/L。地下水中铁、锰离子对去除效果没有显著影响。进水硝基苯浓度对去除效果有显著影响。当进水硝基苯浓度由85μg/L上升至340μg/L时，超滤膜连续工作时间急剧下降，仅为14h；对由硝基苯引起的膜污染，2％CH3，CH3CH2OH清洗效果最佳。作为一项应急处理技术，该工艺可以保障小城镇地区饮水安全。     

高浓度全氟辛酸污染地下水原位修复材料研究

采用有机玻璃柱模拟可渗透反应墙(Permeable Reactive Barrier,PRB),制备球状吸附材料作为PRB填充材料,模拟地下水环境连续进水,探究对高浓度全氟辛酸的去除效果.结果表明:由活性炭、生物炭、沸石和零价铁等制备的复合材料对高浓度全氟辛酸去除效果较好,其中活性炭∶凹凸棒土∶零价铁粉为2∶4∶0.4的材料和其他配比的材料相比,吸附效果更好,比表面积测试结果显示其具有更大的比表面积.当全氟辛酸浓度为50 mg·L^-1时,其去除效果达到95%以上;运行75 d后进水全氟辛酸浓度增加至100 mg·L^-1,连续运行至190 d,去除率为83.4%～96.6%;且pH越低,材料吸附效果越好;吸附4 h左右可达到吸附平衡.该复合材料的试验效果表明该技术可应用于处理高浓度全氟辛酸污染的地下水,实现地下水污染的原位修复.     

氨基化MCM-41介孔分子筛改性超滤膜去除水中Cr（VI）的研究

采用氨基化MCM-41介孔分子筛（NH2-MCM-41）接枝改性聚偏氟乙烯（PVDF）超滤膜,并用于水中重金属Cr（VI）的去除。NH2-MCM-41成功接枝于超滤膜表面,并在表面形成均匀的亲水层,显著提高了膜的抗污染性能,过水通量衰减率从51.4%降低到了24.8%。在pH值3.5,初始浓度20 mg/L时,改性超滤膜对Cr（VI）的吸附可以在5 min达到快速平衡,吸附容量达到2.8 mg/g。超滤实验表明,NH2-MCM-41改性超滤膜对低浓度Cr（VI）进水可以实现进一步净化,在超滤运行时长达到11 h,出水Cr（VI）浓度始终维持在0.5 mg/L以下。因此,本研究通过在膜表面接枝氨基化的MCM-41分子筛,可以有效提升膜的抗污染能力和对重金属的去除能力。     

滞留时间和进水有机物对生物滞留系统除氮的影响

传统雨水生物滞留系统对氮的去除很不稳定。为了提高硝氮和总氮的去除效果,尝试在生物滞留系统底部增加内部淹没区,提供所需的缺氧环境,并延长系统内雨水的停留时间,改善系统的除氮能力。对有淹没区运行条件下进水有机物浓度和滞留时间除氮的影响进行了试验。结果表明系统在有淹没区和无淹没区运行条件下,对NH_4~+-N的平均去除率均在90%以上。无淹没区时系统对NO_3~--N的去除率为21%。有淹没区时(滞留时间2 h)系统对NO_3~--N和TN的去除作用显著提高到74%和78%。淹没运行时进水中COD浓度可以显著影响NO_3~--N的去除效果。当COD浓度为0~100 mg/L,NO_3~--N(7~9 mg/L),去除率随COD浓度的增加而显著升高。滞留时间对NO_3~--N去除效果的影响较为明显,滞留时间从1 h增加到8 h,系统的NO_3~--N平均去除率从21%增加到93%。     

臭氧活性炭去除水中硫醇类致嗅物质的研究

硫醇类物质是南方某江排洪时饮用水中嗅味的主要致嗅物质。以乙硫醇为典型致嗅物质,研究了臭氧活性炭对乙硫醇的去除特性。结果表明,臭氧活性炭对乙硫醇有很好的去除效果,其中臭氧氧化是去除乙硫醇的关键工艺,活性炭发挥的作用有限;去除乙硫醇嗅味的适宜臭氧接触时间是15min,当水质变化不大时,完全氧化水中乙硫醇所需要的有效臭氧投加量(m g/L)为乙硫醇初始浓度(μg/L)的0.04倍。当进水乙硫醇浓度大于100μg/L时,需要增加适宜的预氧化处理,与臭氧活性炭联用才能有效去除水中硫醇类致嗅物质产生的嗅味。     

氨基化MCM-41介孔分子筛改性超滤膜去除水中Cr(Ⅵ)的研究

采用氨基化MCM-41介孔分子筛(NH2-MCM-41)接枝改性聚偏氟乙烯(PVDF)超滤膜,并用于去除水中重金属Cr(VI)研究.NH2-MCM-41成功接枝于超滤膜表面,并在表面形成均匀的亲水层,显著提高了膜的抗污染性能,过水通量衰减率从51.4%降低到24.8%.在p H 3.5,初始质量浓度20 mg/L时,改性超滤膜对Cr(VI)的吸附在5min达到快速平衡,吸附容量达到2.8 mg/g.超滤实验表明,NH2-MCM-41改性超滤膜对低质量浓度Cr(VI)进水可实现进一步净化,超滤运行时长11 h,出水Cr(VI)质量浓度始终维持低于0.5 mg/L,可有效提升膜的抗污染能力和对重金属的去除能力.     

臭氧活性炭去除水中硫醇类致嗅物质的研究

硫醇类物质是南方某江排洪时饮用水中嗅味的主要致嗅物质。以乙硫醇为典型致嗅物质,研究了臭氧活性炭对乙硫醇的去除特性。结果表明,臭氧活性炭对乙硫醇有很好的去除效果,其中臭氧氧化是去除乙硫醇的关键工艺,活性炭发挥的作用有限;去除乙硫醇嗅味的适宜臭氧接触时间是15 min,当水质变化不大时,完全氧化水中乙硫醇所需要的有效臭氧投加量(mg/L)为乙硫醇初始浓度(μg/L)的0.04倍。当进水乙硫醇浓度大于100μg/L时,需要增加适宜的预氧化处理,与臭氧活性炭联用才能有效去除水中硫醇类致嗅物质产生的嗅味。     

钠型活化沸石去除水中氨氮的实验研究

研究了钠型活化沸石去除水中氨氮的性能和影响因素。实验结果表明,钠型活化沸石对氨氮的静态饱和吸附量为58.12 mg/g;当进水氨氮浓度为138.80 mg/L时,在规格为Φ40×1 500离子交换柱中装填500 g粒径为0.5~1.0 mm钠型沸石,控制原水pH在5.5~7.0、滤速在14.0~15.0 m/h范围内,连续过滤43.5 h,对氨氮的去除率稳定在88.6%~92.8%范围内。     

高吸油树脂的合成及对硝基苯的吸附

采用悬浮聚合法合成了丙烯酸系高吸油性树脂。考察了树脂对硝基苯以及对模拟消防废水中硝基苯的吸附性能。研究了吸附树脂量、硝基苯初始浓度、吸附温度、离子浓度、pH等因素对均相含硝基苯的消防水吸附的影响。结果表明:吸附5 h后,对纯硝基苯的最大吸油率为30.5 g/g,吸附10 min后,对硝基苯吸油率达饱和吸油率的50%。当树脂用量为25 g/L时,硝基苯去除率达70%。树脂还具有良好的耐热及耐酸碱性,且离子浓度对吸附率无显著影响,因而能用于多种环境体系。     

β-环糊精聚合物在硝基苯微污染水中的应用

 硝基苯类污水具有难降解、毒性大、易扩散等特点,目前国内外开始对高浓度硝基苯污水的治理进行深入研究,但对微污染水却少有关注.常规给水处理技术无法处理硝基苯微污染水,长期饮用会对人体健康和生态环境产生严重影响.本文选用水不溶性β-环糊精聚合物为吸附剂,研究水不溶性β-环糊精聚合物的制备,考察其对含硝基苯微污染水的吸附作用,讨论固液比、pH等参数对吸附性能的影响,以及β-环糊精聚合物的再生性能.结果表明,每100mL溶液中加入100mg β-环糊精聚合物为最适固液比;聚合物对200μg/L、500μg/L、1mg/L、2mg/L的硝基苯溶液的吸附效率可达到80%以上;最佳吸附时间为2h;环境pH对吸附效率无太大影响;研究选择了乙醇为最佳再生剂,经连续再生4次后,聚合物吸附效率都维持在80%以上.     

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