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1.
竹炭对铜(Ⅱ)离子的吸附性能研究   总被引:2,自引:0,他引:2  
研究了竹炭粒径和用量、吸附时间、温度以及铜(Ⅱ)离子初始浓度等因素对铜(Ⅱ)离子吸附效果的影响.结果表明:竹炭对铜(Ⅱ)离子吸附率随其粒径的减小而增大,而随其用量的增加而增大;铜(Ⅱ)离子初始浓度增大,竹炭对其离子吸附率减小;竹炭对铜(Ⅱ)离子的吸附可在2h达到平衡,最佳吸附温度为30℃.竹炭对铜(Ⅱ)离子具有较好的吸附效果,是较为理想的吸附铜离子的材科.  相似文献   

2.
采用无机盐调控重金属离子的分离方法,研究了含氮螯合树脂M4195在pH=1~5条件下,NaNO3浓度在(0~10 mmol/L)范围下对单双组份Cu(Ⅱ)和Ni(Ⅱ)离子的吸附性能,考察了M4195树脂对Cu(Ⅱ)、Ni(Ⅱ)离子的选择性分离规律。pH=1时,无机盐的引入对双组份中Cu(Ⅱ)和Ni(Ⅱ)离子的吸附量影响不大,不会显著提升Cu(Ⅱ)/Ni(Ⅱ)离子的分离性能。p H=5时,含氮螯合树脂对Cu(Ⅱ)离子的吸附性能随着NaNO3浓度的增加而提升,Cu(Ⅱ)离子吸附量约增大了12%;而Ni(Ⅱ)离子的吸附量随着NaNO3的加入而显著下降,Ni(Ⅱ)离子吸附量约降低了40%,且在NaNO3浓度为0~10 mmol/L时Cu(Ⅱ)/Ni(Ⅱ)离子的分离性能为最佳。这项研究为含盐水体中Cu(Ⅱ)、Ni(Ⅱ)离子的分离去除和纯化提供了新的思路。  相似文献   

3.
中空SiO2微球对重金属Cd(II)的吸附研究   总被引:2,自引:0,他引:2  
采用壳上具有纳米孔的中空SiO2微球从溶液中吸附重金属Cd(II)离子,研究了被吸附溶液的pH值、Cd(II)离子初始浓度、吸附时间等对吸附Cd(II)离子的影响。结果表明,壳上具有纳米孔的中空SiO2微球可用于从溶液中吸附Cd(II)离子。在pH>3的弱酸性溶液中比在pH≤3的酸性条件下中空SiO2微球吸附Cd(II)离子的量要大得多。Cd(II)离子初始浓度小于0.4 mol.L-1时,Cd吸附量随Cd(II)离子初始浓度的影响较小,进一步增大Cd(II)离子初始浓度,吸附量大幅攀升。  相似文献   

4.
利用在线大气与气溶胶检测系统(MARGA)仪器在线观测资料,分析了南京北郊春季大气水溶性离子浓度时间变化特征、水溶性离子之间相关性及其影响因子,为外绝缘设备污秽放电现象和放电机理研究、防污闪措施的制定提供有效参考。结果表明:(1)水溶性离子浓度顺序为NO_3~-SO_4~(2-)NH_4~+K~+Cl~-Mg~(2+)Na~+Ca~(2+),NO_3~-、SO_4~(2-)、NH_4~+是水溶性离子的主要成分;白天水溶性离子浓度大于夜间离子浓度,且白天离子浓度变幅大于夜间离子浓度变幅。(2)主要水溶性离子之间具有较好的同源性,水溶性离子中阴离子主要与NH_4~+结合;水溶性离子主要为细粒子,且NO_3~-、SO_4~(2-)、NH_4~+、Cl~-对空气污染影响较大。(3)风速和风频越大,风对水溶性离子的稀释作用越强,离子浓度下降越快;降水对水溶性离子具有清除作用,沉降率随降水量、持续时间的增大而增大;二次离子的主要生成方式是液相氧化反应;湿润空气有利于Cl~-、Na~+、K~+、Mg~(2+)溶解,增大离子浓度,但使Ca~(2+)浓度减小;温度升高有利于离子扩散。  相似文献   

5.
为了研究聚苯胺(PANI)掺杂离子之间的交换,通过电化学方法分别在金电极上合成了樟脑磺酸(CSA)和盐酸(HCl)掺杂的PANI膜。采用循环伏安法(CV)、电化学阻抗法(EIS)、扫描电子显微镜(SEM)、拉曼光谱法(Raman)研究了两种离子掺杂的PANI在CSA和HCl溶液中的掺杂离子互换。结果表明:离子半径较小的掺杂离子Cl-可以较容易地将PANI中的半径大的掺杂离子CSA-交换出,而反之较难;聚苯胺膜的形貌在掺杂离子交换前后未发生太大变化,具有一定的形貌"记忆"效应。  相似文献   

6.
1 材料结构概况材料结构是指组成材料的原子(或离子、分子)相互结合的方式或构成的形式——相、组织、缺陷………。以及结构要素按一定次序的组合、排列及其相互间的各种联系。材料结构包括以下内容:(1)原子(或离子、分子)的构造:粒子—→原子—→分子。(2)原子(或离子、分子)的结合:金属键;离子健;分子键;氢键………(或二种或几种键同时存在)(3)原子(或离子、分子)的排列:非晶体;准晶体:晶体;晶体十非晶体。  相似文献   

7.
目的研究石英砂负载巯基材料(SFQ)去除Hg(Ⅱ)离子过程中各因素的影响,优化Hg(Ⅱ)离子去除条件.方法采用响应曲面(RSM)试验中的中心组合设计(CCD)方法,以吸附时间、Hg(Ⅱ)离子质量浓度和pH作为试验因子,建立3因素3水平响应曲面回归模型,以Hg(Ⅱ)离子的去除率作为响应值进行全面分析,并验证模型的准确度.结果响应曲面CCD建立的吸附模型对SFQ吸附Hg(Ⅱ)离子拟合度较高,R~2=0.982 2,模型优化所得的最佳条件为:Hg(Ⅱ)离子质量浓度为0.96 mg/L,pH值为3.78,处理时间为102.94 min.在此条件下,Hg(Ⅱ)去除率为92.05%.试验结果与模型预测值符合,理论值与实测相对误差不超过2%.结论 SFQ吸附Hg(Ⅱ)离子去除率的影响因素大小顺序依次为:pH、Hg(Ⅱ)离子质量浓度、吸附时间.SFQ对污水中Hg(Ⅱ)离子去除率较高,可以将SFQ材料应用于含汞废水的处理.  相似文献   

8.
利用批实验方法,研究CO_3~(2-)、HPO_4~(2-)、SO_4~(2-)、Cl~-和腐殖酸(HA)对U(Ⅵ)在氧化石墨烯(GO)上吸附的影响。结果表明U(Ⅵ)在GO上的吸附强烈地受pH值影响。体系中CO_3~(2-)会与U(Ⅵ)离子相互配合生成可溶性配合物,使U(Ⅵ)离子在GO的吸附降低。HPO_4~(2-)会与GO以及铀酰离子络合产生三相配合物,从而对吸附有促进作用。SO_4~(2-)在吸附体系中与U(Ⅵ)离子在GO表面的吸附位点上产生竞争,并在低浓度时与铀酰络合形成可溶性络合物抑制了U(Ⅵ)在GO上的吸附。Cl~-对U(Ⅵ)离子吸附无显著影响。HA对U(Ⅵ)离子在pH<7.0时在GOs上的吸附有促进作用,而在碱性条件下有抑制作用。不同的吸附影响归因于环境离子与U(Ⅵ)的络合,以及与GOs结合能力有关。  相似文献   

9.
粉末活性炭对水中重金属离子的吸附性能研究   总被引:1,自引:0,他引:1  
活性炭是一种具有丰富孔隙结构和巨大比表面积的碳质吸附材料,在污水净化领域具有广泛的应用价值.根据单一变量原则,研究了粉末活性炭对水中重金属离子Cr(VI)、Cu(Ⅱ)和Fe(Ⅲ)的吸附作用.实验结果表明,粉末活性炭能有效去除3种重金属离子,且去除效果受温度、吸附时间、活性炭用量、溶液p H值的影响.随着活性炭用量、温度或吸附时间的增加,3种离子的去除率先增后减,而溶液p H值增加时,Cu(Ⅱ)离子的去除率几乎不变,Cr(VI)和Fe(Ⅲ)离子的去除率却逐渐降低.吸附时间超过30 min时,粉末活性炭对3种离子中的Cu(Ⅱ)离子去除效果最好,去除率达90%以上.Cu(Ⅱ)离子的去除最优条件为40℃(温度)、30 min(吸附时间)、0.15 g(活性炭用量)和2.0(p H).  相似文献   

10.
甲基咪唑类离子液体是一类综合性能优良的反应介质,人们已在其合成、表征和应用方面进行了较为深入的研究.但目前人们对于该类离子液体的结构知之甚少,开展相关的理论研究有助于深入认识离子液体的性质,提供官能化设计的理论依据.离子液体中,"离子对"的结构是理解离子液体结构的基础,是影响离子液体性能的重要因素[1].本文利用量子化学方法系统研究了1-烯丙基-3-甲基咪唑阳离子(Amim )和二氰胺根(DCA-)、氯(Cl-)离子形成离子对的几何结构和相互作用能,揭示了2种离子液体粘度差别的原因.  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.
王慧 《科技信息》2008,(10):240-240
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.  相似文献   

14.
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.  相似文献   

15.
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   

16.
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   

17.
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.  相似文献   

18.
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   

19.
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   

20.
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   

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