HPA/TiO2-WO3催化合成乙酸环己酯的研究

以乙酸和环己醇为原料，采用纳米固载型杂多酸HPA／TiO2-WO3为催化剂，系统研究了合成乙酸环己酯的优化条件．优化条件为：乙酸0．108mol，环己醇0．06mol，催化剂0．3g，反应时间90min，乙酸环己酯收率为84．7％．     

对甲苯磺酸催化合成二乙酸乙二醇酯

以对四苯磺酸为催化剂，由乙二醇和乙酸合成了二乙酸乙二醇酯。当0．2mol乙二醇、0．5oml乙酸、15ml苯和1．0g催化剂一起加热回流分水1．5h，酯收率达94．9％。     

固体超强酸Fe2O3-SO4^2-催化合成乙酸异戊酯

以固体超强酸Fe2O3-SO4^2-为催化剂合成乙酸异戊酯，催化效率高，后处理方便、经济，反应工艺简单，不腐蚀设备。实验结果表明，以固体超强酸Fe2O3-SO4^2-为催化剂，合成乙酸异戊酯的最佳条件为：乙酸的用量0．2mol，催化剂的用量1．25g，反应物摩尔比1：1．2，反应时间3h。     

追风透骨丸的药效学研究

目的：观察追风透骨丸的抗炎镇痛作用和对血流变学的影响．方法：用二甲苯所致小鼠耳廓及乙酸引起小鼠毛细血管通透性的增高试验，观察该药的抗炎作用，用乙酸扭体法研究其镇痛作用；用WTP—B1型毛细血管血液粘度计测定血液流变学指标．结果：追风透骨丸对二甲苯所小鼠耳廓肿胀有明显的抑制作用，并抑制乙酸所致小鼠毛细血管通透性的增高，对乙酸扭体法镇痛实验的研究显示追风透骨丸具有明显的镇痛效应，并能降低小鼠全血高切低切的血粘度．     

乙酸异戊酯的合成实验

乙酸异戊酯的合成实验海南省琼山海南师院（５７１１００）李雄记在高中化学教学中，以乙酸异成酯的合成作为课堂演示实验具有如下优点：酯化装置和操作简单、需时少、成功率高；反应物之一异成酸气味奇奥，而产物乙酸异成酯则具有比乙酸乙酯更加浓郁的水果香味，反应前后...     

一水合硫酸氢钠催化合成乙酸正己酯

研究了以硫酸氢钠为催化剂，乙酸和正己醇为原料合成乙酸正己酯，并考察了反应条件对酯化率的影响．结果表明，在适宜条件下其酯化率可达97．6％．     

非质子酸催化合成乙酸异戊酯工艺的优化研究

以非质子酸为催化剂，以乙酸和异戊醇为原料，对合成乙酸异戊酯的反应进行了研究，探讨了几种不同非质子酸催化剂的影响并分析了醇酸摩尔比、催化剂用量、反应时间、回流温度诸因素对收率的影响．实验结果表明，四氯化锡是合成乙酸异戊酯的良好催化剂；最佳反应条件为：乙酸、异戊醇和四氯化锡的摩尔比为1：1．20：0．02，反应时间为45min，回流温度为130～140℃。满足上述条件酯收率可达93．61％。     

三氯化铁作催化剂实验室制备乙酸已酯

本文阐明了用氯化铁作催化剂制备乙酸已酯的情况，从三个方面进行实验找出制备乙酸已酯的最佳操作条件。     

需要用无水乙酸钾与氢氧化钾制取甲烷吗

需要用无水乙酸钾与氢氧化钾制取甲烷吗四川成都工业学校（６１００８１）田凤岗说：《化学教学》１９９２年第５期刊登了《用无水乙酸钾与氢氧化钾制取甲烷》，对实验室制取甲烷的常规方法进行了改进，文中写到“用几乎不吸水的无水乙酸钾代替易吸水的无水乙酸钠、不潮解...     

新型咪唑啉两性表面活性剂的合成

以十二醇双氧乙烯基乙酸为原料，与二乙三胺反应合成了咪唑啉环，进而合成了乙酸盐型咪唑啉两性表面活性剂，测定了其水溶液的表面张力，起泡性能，临界胶束浓度，讨论了反应条件对表面活性剂性能的影响。     

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.