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1.
海带吸附镉离子的研究   总被引:3,自引:0,他引:3  
采用多细胞褐藻海带对镉离子进行吸附,研究溶液的pH值,初始镉离子浓度对镉离子的吸附特性的影响.发现pH值对镉离子的吸附影响很大,在pH值为1~6时,pH值越高,镉的吸附量越大.在本研究实验条件下,海带吸附镉离子适宜的浓度为小于500mg/L,海带的最高吸附量为125mg/g(干态).溶液中的镉离子与海带上的钙离子发生离子交换作用,交换率占总吸附量的33%.pH=5.93时得到的吸附等温线可用Dubinin-Radushkevich方程拟合.  相似文献   

2.
臭氧化-活性炭吸附镉的条件   总被引:2,自引:0,他引:2  
为改善活性炭对镉的吸附性,将臭氧化技术引入吸附过程,研究活性炭投加量、臭氧活化时间以及溶液质量浓度变化对活性炭吸附镉离子能力的影响。结果表明,对于初始镉离子质量浓度为10mg/L的吸附溶液,最佳臭氧化时间为15min、最佳吸附时间为1h、活性炭的最佳投加量为1.0g时,吸附后镉离子的质量浓度为0.54mg/L;对于镉离子初始质量浓度为15mg/L的吸附溶液,最佳臭氧化时间为30min、最佳吸附时间为1h、活性炭的最佳投加量为1.1g时,吸附后镉离子的质量浓度为0.56mg/L。实验证明,经臭氧活化后的活性炭的吸附能力明显增强,极大的改变了吸附结果。  相似文献   

3.
研究了多孔有机膨润土颗粒对硝酸根离子的吸附行为.试验了有机覆盖剂的用量、吸附时间、pH值以及硝酸根离子的初始浓度对吸附反应的影响.当覆盖剂用量为45%、硝酸根离子初始浓度为0.05mg/L、吸附剂用量为10g/L、pH值为6、吸附时间为60min时,去除率达96%.  相似文献   

4.
固定化啤酒酵母废菌体吸附Pt4+特性的研究   总被引:6,自引:0,他引:6  
用2%海藻酸钠与l%明胶混合为包埋剂固定啤酒酵母废菌体.固定化啤酒酵母废菌体(ISCWB)呈球形.粒径2~3mm.ISCWB吸附作用受吸附时间、溶液pH值、ISCWB浓度和Pt^4 起始浓度等的影响.但不受温度的影响;吸附作用是一个快速的过程.吸附60min达到平衡.但在最初的5min内吸附量可达最大吸附量的88.4%.吸附Pt^4 的最适pH为2.0.在Pt^4 起始浓度200mg/L、固定化菌体浓度1.6g/L、pH2.0和30℃条件下振荡吸附60min.吸附量为44.0mg/g.TEM观察显示,固定化菌体不仅能吸附Pt^4 而且能将Pt^4 还原成Pt^0.从含Pt^4 95.22mg/L和47.6lmg/L的废铂催化剂处理液中回收铂.其吸附率分别为48.44%和60.72%,吸附量为26.97mg/g和17.2lmg/g.以1.0mol/L盐酸作为解吸剂,解吸率达80.2%.在填充床反应器中.固定化菌体的最大饱和吸附量为21.0mg/g.解吸率为80%.该固定化菌体有较好的应用前景.  相似文献   

5.
低压离子色谱分离化学发光检测水中痕量硫离子   总被引:2,自引:0,他引:2  
结合流动注射技术,将低压离子色谱与化学发光联用检测痕量硫离子.在最佳实验条件下,硫离子浓度在 4.0×10-2~1.0 mg/L范围内与发光强度呈良好的线性关系;检测限(3σ)为5.0×10-3mg/L;相对标准偏差为 0.5%(n=11,0.10 mg/L S2-).该方法用于环境水样中S2-的测定,结果令人满意.  相似文献   

6.
粘土-壳聚糖复合吸附剂吸附铬(Ⅵ)离子性能的研究   总被引:1,自引:0,他引:1  
通过壳聚糖与粘土的结合,制备出复合吸附剂,并研究其对Cr(Ⅵ)离子的吸附性能.研究结果表明,与单一的粘土或壳聚糖相比,该吸附剂对Cr(Ⅵ)离子吸附速度快、吸附能力强.吸附除去Cr(Ⅵ)的最佳工艺条件是:壳聚糖与粘土质量比为0.04,pH值4~6,Cr(Ⅵ)离子的质量浓度≤10mg/L,吸附平衡时间为40min,吸附荆用量为8.0g/L.  相似文献   

7.
黄海兰  徐波  曲荣君 《应用科技》2004,31(12):61-62,65
研究了自合成的巯基树脂对Ag^ 、Hg^2 、Cr^3 的静态吸附性能,结果表明,该树脂对3种离子吸附能力强,吸附量分别达6.56、3.25、2.10mmol/g,树脂对各金属离子等温吸附在实验浓度范围内符合兰缪尔(Langmuir)或弗伦德利希(Freundlich)方程.吸附机理研究表明,巯基与金属离子发生了离子交换和配位反应,化学吸附起支配作用。  相似文献   

8.
霍林河褐煤吸附铬离子的实验研究   总被引:1,自引:0,他引:1  
为寻找一种廉价高效的处理含铬废水的吸附剂,用Freundlich等温式研究了霍林河褐煤吸附铬离子的等温吸附过程。根据Clapeyron—Clausius方程获得了较小的吸附热,△H仅为-5.83kJ/mol,表明褐煤吸附铬离子是物理吸附过程。同时研究了酸度、溶液浓度及、吸附时间对褐煤吸附铬离子的影响。结果表明:随着pH值增加,平衡吸附量减小;当pH为2、铬离子的质量浓度为50mg/L、吸附100min时,吸附量可达3.8mg/g。用褐煤进行含铬废水的处理具有一定的实际意义。  相似文献   

9.
从不同来源的细菌菌株中.筛选得到一株吸附Pt^4 能力较强的菌株XPO5,经鉴定为弗劳地柠檬酸杆菌(Citrobacter freudii);并研究了死的XP05菌体吸附Pt^4 的特性.死的XP05菌体吸附Pt^4 的最适pH值为2.0.该菌体对Pt^4 的吸附是一个快速的过程.在最初的8min内,吸附量可达到最大吸附量的78.1%,吸附lh即可达到平衡.在10—75℃的范围内.菌体对Pt^4 的吸附量随着温度的升高而增加.在2g/L菌体、Pt^4 起始浓度225mg/L、pH2.0和30℃条件下,振荡吸附60min,吸附量达64.4mg/g.Cu^2 、Ca^2 、Co^2 、Au^3 、Pb^2 、A1^3 等离子能不同程度地抑制XP05菌体对Pt^4 的吸附能力.从含有Pt^4 l11.76mg/L的废铂催化剂处理液回收铂,其吸附率达61.3%,吸附量为30.65mg/g.  相似文献   

10.
通过改变震荡时间、不溶性腐殖酸的投加量、pH值、铀酰离子的浓度等因素,研究不溶性腐殖酸(insolubilized humic acid简写IHA)对铀酰离子(UO2+2)的吸附作用.实验表明,在铀酰离子的浓度在4.79×10-5 mol· L-1以上,pH≈7时,不溶性腐殖酸对六价铀有较好的吸附能力,吸附效率在96%以上.对于浓度为1.60×10-4 mol·L-1的铀溶液,不溶性腐殖酸的用量在0.015 g左右时,吸附可达饱和.IHA的投加量、pH值、铀酰离子的浓度、震荡时间等对吸附具有明显的影响,研究表明,IHA对铀酰离子的吸附符合一级反应特征,实验数据服从Freundlich等温式.  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.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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