牡蛎壳对染料废水吸附的研究

以牡蛎壳为原料,通过煅烧方法制备牡蛎壳吸附剂.考查了溶液pH值、牡蛎壳煅烧温度、煅烧时间、粒径、吸附剂用量、初始浓度和吸附时间等因素对直接大红4BS和孔雀石绿吸附性能的影响.结果表明,直接大红4BS和孔雀石绿的最佳pH分别为1.0和8.0.在200℃煅烧5h后,采用100目0.8g吸附剂吸附染料,去除率达最大值.运用三种动力学模型对吸附过程进行拟合,结果表明吸附过程可以很好地用准二级动力学方程描述.吸附等温线用Langmuir方程的拟合效果优于Freundlich方程,吸附剂再生后,可循环使用5次以上.     

经离子液体水溶液预处理玉米芯对亚甲基蓝吸附性能的研究

目的:采用离子液体[Bmim]Cl水溶液对玉米芯进行预处理,探讨该吸附剂对废水中亚甲基蓝的吸附效果。方法:分别进行静态吸附动力学和热力学研究,采用准一级动力学方程、准二级动力学方程、Elovich和颗粒内扩散方程四种动力学经验方程对动力学过程进行分析;采用Freundlich、Langmuir、DR和Temkin四种吸附等温方程对热力学过程进行分析。结果:拟合结果表明,吸附过程符合准二级动力学方程,Langmuir等温吸附模型能够较好地描述玉米芯对亚甲基蓝吸附的热力学过程。此外,较高的温度有利于吸附,吸附过程为吸热过程。结论:经离子液体预处理后的玉米芯具有较好的吸附能力,吸附行为符合Langmuir吸附等温线,反应级数符合准二级反应动力学特征。     

柚子皮对水中六价铬的吸附性能研究

采用柚子皮制备生物吸附剂用于去除水中的Cr(VI),考察了p H值、柚子皮投加量、柚子皮粒径、溶液离子强度、反应温度等因素对吸附效果的影响。结果表明,当溶液中Cr(VI)离子初始浓度15mg/L、p H 1.5、反应温度25℃、柚子皮投加量1.0g/100 m L、吸附时间7 h时,Cr(VI)离子去除率可达90%以上。柚子皮对Cr(VI)离子的吸附过程可以用Langmuir和Freundlich吸附等温模型来描述,吸附等温线线性相关性均较显著,吸附过程符合准二级动力学方程。柚子皮对水中Cr(VI)离子吸附性能较好,且运行成本低,可推广应用于水中重金属离子的治理。     

多孔三聚氰胺甲醛树脂的合成及吸附性能分析

采用溶剂热法合成多孔三聚氰胺甲醛树脂,并考察了其对亚甲基蓝、甲基橙和罗丹明B的吸附性能。结果表明,吸附剂用量、染料初始浓度、pH、吸附时间等对吸附效果均有一定影响,在最佳条件下,多孔三聚氰胺甲醛树脂对3种染料的去除率分别达到82%、92%和95%以上,吸附效果良好。通过研究吸附动力学曲线、吸附等温线探讨吸附机理,发现多孔三聚氰胺甲醛树脂对3种染料的吸附过程均符合准二级动力学模型,用Freundlich方程对甲基橙和罗丹明B等温吸附拟合效果较好;对亚甲基蓝的吸附则同时符合Langmuir和Freundlich等温吸附模型。     

活性炭纤维对水中痕量六价铬的吸附性能研究

以聚丙烯腈基活性炭纤维(PAN-ACF)为吸附剂,分别进行空气热氧化、硝酸浸渍、过氧化氢浸渍改性处理,对改性处理的PAN-ACF样品进行表征,包括SEM表面形态、比表面积BET、傅里叶变换红外线光谱(FTIR)表面基团以及总表面酸性基团;研究对痕量六价铬的吸附效果,分析PAN-ACF改性对吸附容量的影响。经过过氧化氢浸渍改性处理的ACF3炭微晶尺度变小,导致结构无序化,较大地提升了比表面积,但表面含氧官能团增势不明显;其对微污染水中六价铬的吸附效果最佳,吸附等温线相对于Langmuir方程,更符合Freundlich方程。     

磁性构树叶材料的制备及其对阳离子染料的吸附性能

目的:以构树叶为原料,经离子液体预处理后,采用原位共沉淀技术制备磁性构树叶材料,并探讨该吸附剂对阳离子染料的吸附效果。方法:利用红外光谱(IR)和热重分析(TG)对该材料进行初步的结构表征,在此基础上研究了磁性构树叶作为吸附剂对阳离子染料甲基紫、次甲基蓝和罗丹明B的吸附性能,探讨了反应时间、固液比、反应温度、初始浓度对其吸附性能的影响,选择甲基紫的吸附过程对其用四种动力学经验方程和四种热力学模型进行分析。结果:拟合结果表明,吸附过程符合准二级动力学方程,说明该吸附过程以化学吸附为主,其等温吸附过程可以用Langmuir模型描述,说明该吸附以单分子层吸附为主,并提出修订的Langmuir模型。此外,该吸附过程是自发放热的,低温有利于反应的进行。结论:采用原位共沉淀技术制备磁性构树叶材料具有较好的吸附能力,吸附行为符合准二级动力学方程,以及Langmuir吸附等温线。     

壳聚糖/聚乙烯醇共混膜对十二烷基苯磺酸钠吸附的研究

采用流涎法制备壳聚糖与聚乙烯醇的共混膜（CS/PVA）.研究了共混膜吸附剂对SDBS的吸附性能,考察了溶液pH值、吸附时间、浓度、温度的影响.结果表明,吸附过程可以很好地用准二级动力学方程描述,吸附等温线用Langmuir方程的拟合效果优于Freundlich和Tempkin方程.在热力学研究表中,ΔGo〈0,ΔHo〉0,ΔSo〉0,表明此吸附过程是自发、吸热和熵增加的过程.     

钢渣-蒙脱石颗粒吸附剂对水中Pb2+的去除研究

以钢渣及蒙脱石为原料,工业淀粉为添加剂,制备钢渣-蒙脱石颗粒吸附剂并将其做为实验材料,研究了其对水中Pb2+的吸附性能,探讨了影响吸附的因素.研究结果表明:钢渣-蒙脱石颗粒吸附剂在溶液pH为7和吸附反应时间120min的条件下吸附效果最佳.在此环境条件下,吸附剂用量为9.0g/L、对初始浓度为100mg/L的 Pb2+溶液的去除率可达到93%,钢渣-蒙脱石颗粒吸附剂在以上条件下对Pb2+的吸附量为10.3mg/g;钢渣-蒙脱石颗粒吸附剂吸附重金属离子时可用二级动力学方程进行拟合,对Pb2+的相关系数为0.9993;且符合Langmuir方程,其相关系数为0.9929;对Pb2+的理论饱和吸附量为12.61mg/g.     

剩余活性污泥对水中Cr（Ⅵ）、Cd（Ⅱ）的吸附性能研究

以剩余活性污泥作吸附剂对水中Cr（Ⅵ）、Cd（Ⅱ）的去除进行了探讨。考察了pH值、吸附时间、吸附剂投加量和金属离子初始浓度对吸附去除率的影响。剩余活性污泥对Cr（Ⅵ）、Cd（Ⅱ）均遵循Langmuir等温线,且对Cr（Ⅵ））的吸附能力大于Cd（Ⅱ）。     

啤酒酵母对Zn~(2+)、Mn~(2+)和Cu~(2+)的吸附探究

文中利用啤酒酵母去除模拟废水中Zn2+、Mn2、Cu2+,通过对预处理试剂、吸附温度、吸附液pH值与浸泡时间等因素进行正交分析,确定了影响吸附的主要因素是酸度和预处理试剂.研究pH值、离子初始浓度、吸附时间、离子强度等条件对吸附率的影响,结果表明,用NaOH浸泡后2h,在pH=5~6时吸附效果最好.用吸附等温线Langmuir(exe)、Freundlich和Temkin方程拟合,相关性都比较好.用不同的吸附动力学方程描述啤酒酵母吸附金属离子的最优模型为Elovich方程.     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.     

Improvement of one-cycle controller by use of proportional integral differential controller

1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…     

库克斯顿城堡

城堡, 是欧洲典型的建筑之一, 每个城堡都有一个美丽的传说或是一段历史。从本期开始, 我们将推出“城堡之旅”, 带各位读者去浏览、观赏欧洲各地的城堡, 开始一段文化与历史的旅途!     

The Reader Response Approach to Teaching of English Literature

During interview with English majors, it was found that a majority of students expressed disappointment with their experience of English literature classes. Students' dislike of learning English literature appears to be the major problem of teaching English literature in China. Reader response approach is a good way to solve this problem. In this paper, I explain the rationale behind the reader response approach, such as its origin, definition, features, assumptions, and strategies. Then I illustrate how reader response approach works as a teaching strategy by presenting several teaching models. At last I evaluate its usefuiness for teachers and present the advantages of reader response approach in Chinese context.