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1.
啤酒酵母菌对Pb~(2+) 与Zn~(2+) 的生物吸附规律   总被引:10,自引:0,他引:10  
研究了啤酒酵母菌体对工业废水中重金属离子Pb2+,Zn2+的生物吸附规律·实验结果表明,啤酒酵母菌体对Pb2+的吸附效果比对Zn2+的吸附效果要好;啤酒酵母菌体对铅离子和锌离子的吸附作用与pH值密切相关,最佳的pH值范围均是4~6·体系pH=4时,啤酒酵母菌对Pb2+的吸附量最大,为98 20mg/g;在pH=5 5时,啤酒酵母菌对Zn2+的吸附量最大,为13.89mg/g·在初始铅、锌离子浓度均为1mmol/L的水溶液中,吸附时间为15min即达到吸附平衡,该吸附过程具有一级动力学反应特征·  相似文献   

2.
悬浮酵母菌对重金属Cd2+的吸附研究   总被引:7,自引:1,他引:6  
研究了悬浮酵母菌菌株对水相中Cd2+的吸附过程,讨论了各试验因素对吸附效果的影响.结果表明,悬浮酵母菌菌株对水相中的Cd2+有吸附作用;吸附过程10 min就达到平衡;pH对吸附过程影响较大,在pH=5.41时,镉离子的吸附效果最好;溶液的初始质量浓度也是影响吸附效果的主要因素,在初始质量浓度为228.4 mg/L,悬浮酵母菌用量为14 g/L时,镉离子的吸附率达到99%.测试的红外光谱结果显示:悬浮酵母菌对Cd2+的主要吸附位点为-OH,C=O,P=O,-NH2及S=O.  相似文献   

3.
硅藻土对水相中啤酒酵母菌的吸附研究   总被引:1,自引:0,他引:1  
通过考察吸附条件对吸附率及吸附负载量的影响,研究了吉林长白硅藻土对水相中啤酒酵母菌的吸附特性·实验结果表明,硅藻土对啤酒酵母菌有较好的吸附效果;硅藻土对啤酒酵母菌的吸附在20min就达到吸附平衡;pH值在7 5时吸附效果最好;在硅藻土用量为20g/L,溶液中啤酒酵母菌质量浓度为40g/L时,硅藻土对其吸附率为64%,硅藻土吸附啤酒酵母菌的吸附负载量为160mg/g·吸附温度对该吸附过程影响不大,室温下操作即可·经测试显示,吉林长白硅藻土粒度小、比表面积大,其优势藻属为小环藻和直链藻,且其表面孔洞通畅,层次分明,分布均匀且排列有序,是一种天然的优质吸附剂·  相似文献   

4.
Norcardia Amarae菌吸附Hg~(2+)的研究   总被引:8,自引:2,他引:8  
研究了Norcardiaamarae菌体对水相中重金属离子Hg2+的吸附特性,并测定了菌体的ξ电位 pH曲线及其等电点数据·结果表明,Norcardiaamarae菌体对Hg2+具有良好的吸附效果;该吸附是一个快速过程,在2min以内就达到吸附平衡;在较宽的pH值范围内(4 0~12 0),Norcardiaamarae菌体对Hg2+去除率均达96%以上,在pH>12 0时溶液开始产生Hg(OH)2,此时Hg2+去除率反映的不仅是生物吸附的效果,而且是沉淀与吸附共同作用的结果;吸附温度为23℃时,Hg2+去除率最高;用该菌吸附质量浓度为400mg/L的Hg2+溶液,Hg2+的去除率可达97%·...  相似文献   

5.
啤酒酵母菌对Pb2+与Zn2+的生物吸附规律   总被引:6,自引:0,他引:6  
研究了啤酒酵母菌体对工业废水中重金属离子Pb2 ,Zn2 的生物吸附规律.实验结果表明,啤酒酵母菌体对Pb2 的吸附效果比对Zn2 的吸附效果要好;啤酒酵母菌体对铅离子和锌离子的吸附作用与pH值密切相关,最佳的pH值范围均是4~6.体系pH=4时,啤酒酵母菌对Pb2 的吸附量最大,为98.20mg/g;在pH=5.5时,啤酒酵母菌对Zn2 的吸附量最大,为13.89mg/g.在初始铅、锌离子浓度均为1mmol/L的水溶液中,吸附时间为15min即达到吸附平衡,该吸附过程具有一级动力学反应特征.  相似文献   

6.
实验采用紫外分光光度法,以聚丙烯树脂和聚丙烯酰胺树脂作为吸附剂,对Pb2+进行吸附研究,考察吸附温度、吸附时间、金属离子的浓度、pH 值、吸附剂用量等影响因素对吸附效果的影响,从而确定最佳的吸附条件. 结果表明:吸附温度为20 ℃,吸附时间为20 min,吸附剂树脂用量为20 g·g-1,pH 值为4.0,Pb2+溶液浓度为300 mg·L-1时,吸附效果最佳.  相似文献   

7.
硅藻土对诺卡氏菌的吸附作用   总被引:4,自引:1,他引:3  
研究了吉林长白硅藻土吸附水相中诺卡氏菌的吸附过程,讨论了吸附时间、硅藻土用量、溶液初始pH值和吸附温度等实验条件对吸附效果的影响·实验结果表明,硅藻土对水相中的诺卡氏菌具有较好的吸附效果·该吸附过程进行得较快,在20min左右即可达到吸附平衡;在溶液初始pH值为7 0~9 0内都有较好的吸附效果;温度对吸附过程的影响不大,室温条件下操作即可;在诺卡氏菌浓度一定的条件下,适量增加硅藻土用量可以提高吸附效果·扫描电镜分析结果表明,硅藻土表面的微孔和诺卡氏菌表面的菌丝可能是吸附过程的主要吸附位·  相似文献   

8.
海藻酸钠吸附铜离子的研究   总被引:14,自引:1,他引:14  
研究了用海藻酸钠作为吸附剂去除水相中的Cu2 ,以及吸附过程中试验条件对吸附效果的影响·结果表明:吸附过程在10min左右就达到了平衡;在pH=6时吸附效果达到最佳;吸附温度以30℃左右为宜;海藻酸钠对Cu2 吸附的最大负载量为144~150mg/g·铜离子去除率的大小与水相中铜离子的初始质量浓度有关,对含铜量较高的水样(如铜离子质量浓度为800mg/L),海藻酸钠对溶液中Cu2 的去除率最高达81%,对含铜量较低的水样(如铜离子质量浓度为40mg/L),Cu2 的去除率达99 5%;因此采用海藻酸钠进行二次吸附,溶液中的Cu2 的残余质量浓度低于国家污水综合排放标准中铜离子的最高允许排放质量浓度·  相似文献   

9.
固定化啤酒废酵母对Pb2+的吸附   总被引:1,自引:0,他引:1  
用2 %海藻酸钠与1 %明胶混合为包埋剂固定啤酒酵母废菌体,研究固定化啤酒废酵母对Pb2 的吸附行为.利用原子吸收光谱法测定Pb2 含量.结果表明,固定化啤酒废酵母吸附Pb2 受吸附时间、吸附温度、溶液pH值、酵母添加量和Pb2 起始浓度等因素影响.实验确定了固定化啤酒废酵母对Pb2 的最佳吸附条件.即:pH为3.0~5.0,Pb2 浓度为100 mg·L-1,酵母添加量1.2 g·L-1,吸附温度25 ℃,吸附时间120 min.在一定的浓度范围内啤酒废酵母对Pb2 的吸附符合Langmuir吸附模型和Freundlich吸附模型,但符合Freundlich吸附模型的程度更优.  相似文献   

10.
初步探讨了啤酒酵母菌吸附铀的特性,考察了溶液pH值、铀的初始浓度等对吸附能力的影响,得出最佳pH值为6.0,结果表明:啤酒酵母菌对铀的吸附量大,由Langmuir吸附模型得出q_(max)=196.1mg/g,最后研究了铀的解吸,用Na_2CO_3或NaHCO_3解吸效果较好,解吸率分别为87.8%和87.2%。  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.
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   

18.
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   

19.
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   

20.
<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   

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