水洗废啤酒酵母去除电镀废水中镉的工艺试验研究

以水洗废啤酒酵母为吸附剂,采用自制试验装置,对电镀废水中重金属镉进行吸附-沉降工艺试验研究.结果表明,在废水处理量1L,废水中镉质量浓度为26mg/L,pH=7,吸附剂用量40g/L(湿重),室温约25℃,搅拌速度1000r/min,吸附时间30min,沉降240min的条件下,废水中镉的吸附率及吸附—沉降后镉的去除率分别达96.59%和94.25%.三级处理后废水中镉达到排放标准(0.1mg/L).连续处理效果比间歇处理效果略差.采用扫描电子显微镜及表面能谱,分析了水洗废啤酒酵母对镉的吸附机理.结果表明,水洗废啤酒酵母对镉的吸附过程中细胞结构受到破坏,吸附过程有化学络合和静电吸附作用存在.     

对溴苯基重氮氨基偶氮苯双波长分光光度法测定镉

研究了对溴苯基重氮氨基偶氮苯与镉(Ⅱ)的显色反应,建立了双波长分光光度法测定镉的新方法.研究结果表明:在氨水介质中,在TritonX-1 00存在下,镉(Ⅱ)与对溴苯基重氮氨基偶氮苯能形成稳定的红色络合物,最大吸收正峰为492 nm,负峰为410 nm处.选定492 nm为测定波长,410nm为参比波长.镉(Ⅱ)的量在0～0.6μg/mL范围内符合比尔定律.表观摩尔吸收系数为1.8×105L·mol-1·cm-1,比单波长提高了(1.1×105 L·mol-1 ·cm-1)64％.加入混合掩蔽剂可消除常见共存离子的干扰.该方法用于水样中镉含量的测定,回收率为102％ ～104％,RSD为2.6％～3.2％(n=5).     

1-(5,7-二溴-8-喹啉)-3-(偶氮苯)-三氮烯的合成及作为镉的光度分析试剂

合成了新显色剂1-(5,7-二溴-8喹啉)-3(偶氮苯)-三氮烯(DBQABT),其结构由红外光谱和元素分析确证.研究了DBQABT与镉的显色反应在.pH9.8～10.5的硼酸盐缓冲介质中,镉与该试剂形成1:2的橙红色络合物,其最大吸收波长位于525 nm处,表观摩尔吸光系数为2.10×105L·mol-1·cm-1,镉的浓度在0～20μg/25 mL范围内符合比尔定律在掩蔽剂存在下,常见离子基本不干扰.用于工业废水中微量镉的测定,结果与原子吸收法一致.     

4-磺酸基苯基重氮氨基偶氮苯光度法测镉

在 pH11.0的 NH4Cl-NH3·H2O缓冲溶液中,在OP表面活性剂存在下,4-磺酸基苯基重氮氨基偶氮苯能与镉生成2:1红色配合物.配合物的最大吸收峰位于522 nm.镉用量在(0～15) μg/25 mL范围内符合比尔定律,相关系数为0.998,摩尔吸光系数ε =1.88×10 5L · mol -1·cm -1.用拟定方法测定废水中微量镉,结果满意.     

聚苏木精/氧化石墨烯修饰玻碳电极测定水样中痕量铅和镉

将玻碳电极用氧化石墨烯修饰后电聚合上苏木精聚合膜,利用该修饰电极差分脉冲溶出伏安法同时测定铅和镉.对支持电解质及其缓冲溶液、富集电位及富集时间测定条件进行了优化.在0.1 mol/L pH 3.5的NaAc-HAc缓冲液中,以此修饰电极为工作电极,在-1.1 V处搅拌富集220 s,用差分脉冲伏安法分别测定-0.58 V和-0.8V处的氧化峰电流.结果表明,该电极显著提高了铅和镉的电化学响应信号.在优化条件下,峰电流与铅和镉的浓度在0.01~1μmol/L范围内呈良好的线性关系,相关系数为0.991~0.995.检出限分别为8 nmol/L(Pb2+)和1 nmol/L(Cd2+)(S/N=3).将该法用于实际水样中痕量铅和镉的测定,回收率为92.2%~105.8%.     

浸矿细菌抗镉性能的试验研究

通过在培养基中加入一定浓度的镉离子,确定浸矿细菌对镉离子的抗性以及镉对浸矿细菌生长的影响.研究表明:不同浓度的镉离子对细菌的生长和活性起不同的作用.菌液中镉离子浓度低于0.1 mmol/L时,镉离子是浸矿细菌的营养物质,对细菌的生长起促进作用;随着镉离子浓度的增高,对细菌的生长起一定的抑制作用.浸矿细菌表现出良好的抗镉能力,镉离子浓度在高达8 mmol/L时,浸矿细菌仍然生长,保持好的活性.菌液中镉离子浓度为10 mmol/L时,浸矿细菌的生长受到影响.     

多代镉暴露对大型溞(Daphnia magna)生活史及压力反应的影响

研究长期多代镉暴露对大型溞(Daphnia magna)生活史特征和新污染物耐性的影响.将大型溞(Daphnia magna)暴露于两个浓度镉(低浓度,0.5μg/L;高浓度,2.0μg/L),10代后进行生活史试验,评价不同浓度镉对大型溞生活史的影响;10代暴露后,在对照下培养1代进行更高温度(30℃)镉暴露(6.0μg/L).结果显示:与对照比,总体上种群镉暴露后繁殖率降低;高镉长期暴露后对新压力的耐性低于对照但高于低镉暴露(0.5μg/L).     

2-羟基-4-磺酰氨基苯-3-(4-硝基苯)-三氮烯的合成及与镉的显色反应

合成了新的三氮烯试剂--2-羟基-4-磺酰氨基苯-3-(4-硝基苯)-三氮烯,并研究了其在Triton X-100表面活性剂存在下与镉的显色反应.在pH=11.0～12.0的Na2B4O7-NaOH缓冲溶液中,该试剂与镉形成3:1型浅黄色配合物,配合物的最大吸收峰位于λ=535 nm处,表观摩尔吸光系数为1.46×105L·mol-1·cm-1,ρ(Cd2 )在0～480μg/L时符合比尔定律.用拟定方法测定废水中的微量镉,结果满意.     

一株耐铀镉真菌菌株的筛选及其耐铀镉特性的研究

从生长在铀尾矿库区的博落回的根系中,分离出了一株耐铀镉真菌菌株A-2。在固体培养基上,铀和镉对该菌株的最低抑菌浓度(MIC)为160 mg/L和160mg/L,而在液体培养基中,铀和镉对该菌株的MIC为80 mg/L和80 mg/L。经形态学观察和分子鉴定,该菌株属于镰刀菌属,其GenBank登录号为MH978624,可命名为Fusarium sp. A-2。进一步的试验研究结果表明,该菌株在铀镉胁迫下会分泌大量草酸、苹果酸和丁二酸,与铀镉络合,降低了铀镉对菌株的毒性,这可能是该菌株具有高耐铀镉性及能减轻铀镉毒害的机理之一。该菌株在土壤铀镉复合污染治理中具有潜在应用前景。     

镉超高灵敏显色反应的研究

本文研究了高灵敏测定镉的光度法,在阿拉伯胶存在下,在0.02—0.16mol/L硫酸介质中,镉与碘化物和罗丹明6G生成离子缔合物。该缔合物最大吸收波长为525mn,表观摩尔吸收系数ε525为1.6×106L·mo1-1·cm-1,镉浓度在0—2μg/25ml符合比耳定律。考察了共存离子的干扰影响,该法可用于测定水中痕量镉。     

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.     

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.     

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

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     

Call for Papers

<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     

Journal of Donghua University ( English Edition) Contents of Volume 31

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