微型滴定分析化学实验探索

通过对常规分析化学实验仪器进行微型化研制,用自制的微型滴定装置,对分析化学实验进行了一系列微型化滴定实验探索,结果表明:当试剂用量降低到原用量的1/5~1/10时,仍能得到符合常规分析的准确度和精密度要求,从而节约了实验试剂、实验经费和时间,提高了学生的操作能力,同时大大减轻试剂对环境的污染。     

滴定分析实验微型化探索

采用市售5mL微型滴定管,对分析化学实验中的部分滴定分析实验进行了微型化探索．试剂用量可减少为常规用量的五分之一,且不影响分析结果的准确度和精密度．微型滴定法既可大幅减少试剂用量及废液排放量。又培养了学生更高的分析操作技能,社会经济效益显著．     

甲醛法测定硫酸铵中氮含量的微型化研究

对典型的大学分析化学实验—甲醛法测定硫酸铵肥料中氮含量实验，进行了微型化设计和可行性研究，实验结果表明，实验微型化不仅节约了大量的化学药品，减少有毒试剂的排放，而且微型实验结果令人满意。     

微型化学实验介绍

微型化学实验,是近年来国外日益广泛使用的一种实验方法,即在一些专门设计的微型化的仪器装置中进行的化学实验。其药品和试剂的用量为常规实验的数十分之一,甚至千分之一。微型实验与微量实验是两个不同的概念。在分析化学中把试样用量小于     

微型化学实验中加液管的开发及应用

微型化学实验是在微型化的仪器装置中进行的化学实验,其试剂用量比对应的常规实验节约90%以上.微型实验有两个基本特征:试剂用量少和仪器微型化.微型化实验不是常规实验的简单缩微或减量,而是在微型化的条件下对实验进行重新设计和探索,达到以尽可能少的试剂来获取尽可能多的化学信息[1].     

水的总硬度测定的半微量研究

本文用常量分析仪器来进行半微量实验,在满足常量分析滴定的准确度和精密度的前提下,减少试剂的用量,通过对EDTA滴定自来水总硬度的试剂用量进行常量、1/2常量、1/5常量及1/10常量的结果进行处理、比较,探究在大学实验教学中用EDTA测定自来水中总硬度的半微型化实验的最适宜试剂用量.通过实验得出：试剂用量为常量的1/2及1/5时,能满足半微型化实验的要求.     

微型实验在无机性质实验中的应用

近年来，国外在中学化学教学、大学基础实验、乃至医药、工业分析中越来越广泛地使用微型化学实验（microscalechemicalexperiment）方法．所谓微型实验，就是在一些微型化的仪器中进行的化学实验，其试剂的用量是常现实验的数十分之一至千分之一，这一实验技术的应用，对节约药品、减少环境污染都大有神益．近年来，我们将微型实验技术引进到无机性质实验中，经过反复试验、改进，不但将试剂用量降到最低点，而且实验现象也十分明显．现已在学生实验中应用，取得了良好的效果．1微型实验仪器的选用通常微型实验使用的仪器有井穴板、多用滴…     

碳酸氢钠分解实验的微型化改进

<正>我在学习之余发现,近年来随着新高考模式的推广,微型化学实验越来越受到命题者的重视,也逐渐深化到我们的高中化学学习中。查阅资料后,我发现:微型化实验是在专用的微型化的仪器中,用少量的试剂进行的化学实验,微型化实验具有试剂用量少、操作简单、污染最小化、节约     

中学化学实验微型化探究

微型化学实验是指在微型的仪器装置中进行的化学实验。它是20世纪70年代后期在减少污染、保护人类的背景下应运而生的一种化学实验新技术。微型化学实验基本特征是：1．实验仪器微型化．化学试剂用量少：2．微型化学实验不是简单地将常规化学实验微缩或减量．而是在微型化的条件下对化学实验进行一次深入的再认识、再研究,以达到以尽可能少的试剂来获得最为有效的化学信息的目标．也对常规实验进行变革性的再表现．     

优化实验设计彰显环保精神

化学教学的一个重要特征,就是实验．它不仅是探究化学问题的主要手段,也是化学学科的主要内容．随着人们环保意识的加深,化学教学中的实验模式也在发生着变化,一种试剂用量少、器材简单的实验模式——微型实验,悄然兴起．本文主要从演示实验微型化、探究实验微型化两个方面来阐述如何优化微型化学实验的设计,以彰显环保精神．     

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?     

Western and Eastern culture differences in commercial field

The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity.     

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…     

风的曲线

Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose.