异烟肼的荷移光谱测定方法研究

研究了异烟肼与7,7,8,8-四氰基对二次甲基苯醌(TCNQ)、四氯苯醌(TCBQ)和氯冉酸(chloranilicacid)的荷移反应,对反应条件进行了优化.实验指出,异烟肼与7,7,8,8-四氰基对二次甲基苯醌(TCNQ)的反应在丙酮介质中进行,其络合物分别在744nm和845nm处有较强光吸收,表观摩尔吸光系数为7.6×102L·mol-1·cm-1和1.4×103L·mol-1·cm-1,异烟肼的浓度在30—300mg·L-1范围内符合朗比定律.异烟肼与四氯苯醌和氯醌酸的反应则在乙醇介质中进行,形成络合物的最大吸收波长分别为480nm和530nm,表观摩尔吸光系数分别为1.0×103L·mol-1·cm-1和5.5×102L·mol-1·cm-1.异烟肼的浓度分别在2—200mg·mL-1、50—300mg·L-1范围内符合朗比定律.3种方法相对标准偏差分别为0.88%、1.3%和1.6%(n=8).应用拟定的方法测定异烟肼制剂的含量,结果与标准方法一致.     

异烟肼一次氯酸钠的化学发光反应研究

提出了异烟肼一次氯酸钠化学发光新体系．结合流动注射技术，建立了一种新的测定异烟肼的流动注射化学发光新方法．该法选择性较好，操作简单，精密度好试剂易得．异烟肼在1．0×10－6～1．0×10－4g·ml－1浓度范围内与化学发光信号强度呈线性关系．检出限为2．7×10－7g·ml-1．RSD=2．4％（n＝11；Cs=5．0×10－6g·ml－1）．     

水杨醛异烟酰腙的合成与生物活性测定

用异烟肼与水杨醛进行反应,合成了水杨醛异烟酰腙,产品通过UV、IR进行了表征;通过药敏纸片实验以及MIC实验对产品进行了生物活性的测定.对大肠杆菌、奇异变形杆菌、金黄色葡萄球菌、白色链球菌四种菌进行了实验,其中异烟肼缩水杨醛对奇异变形杆菌的抑菌效果明显.在药敏纸片实验中,抑菌直径为11 mm,在MIC实验中测出最低抑菌浓度为1.8×10~(-4)mol/L.     

W-CDMA系统中的Turbo Code仿真

在第三代移动通信系统W CDMA和CDMA2 0 0 0中 ,turbocode在高速数据传输业务方面已倍受青睐 .本文给出了turbocode在瑞利衰落信道和加性高斯白噪信道下的性能仿真结果 ,并在各种不同条件下与卷积码的性能进行了比较 .得到了较为可信的仿真结果 .     

水杨醛缩异烟肼Schiff碱的室温固相合成及光谱性质

以水杨醛、异烟肼通过室温固相反应,成功合成了水杨醛缩异烟肼Schiff碱。通过熔点、元素分析、UV、IR和1H NMR对其结构进行表征,并对其光谱性质进行了研究。     

用交流示波极谱法测定工业废水中的微量汞

运用交流示波极谱法测定工业废水中的微量汞,对EDTA滴定Hg2 + 的条件进行了研究。在pH =6的HAc-NaAc缓冲溶液中并有Br-存在时,Hg2 + 在金电极上有敏锐的切口[1 ] ,可用于指示终点。实验结果表明,Hg2 + 的含量在0 .1 0—1 0 .0mg·mL-1 范围内,滴定的准确度能满足分析要求。其RSD为2 .4 3—3 .1 5‰,加标回收率为98.0 0—1 0 3 .0 0 %。     

隐含条件在解题中的作用

所谓隐含条件是指题目中含而不露 ,不易觉察的固有条件 ,它隐蔽在题设的背后 ,容易被人们忽视 .解题时 ,只有深挖题目中的隐含条件 ,并加以充分利用 ,才可能使问获得迅速而正确的解决 .那么 ,隐含条件在解题中起什么作用呢 ?1　隐含条件的化简作用有些数学问题的解答 ,虽然也可以不依赖于深层次的隐含条件 ,但若能借助于隐含条件进行转化 ,却能避开繁杂的运算 ,使问题获得快速简洁的解决 .例 1　 (2 0 0 0年全国高考理科题 )设函数 ｆ(ｘ)= ｘ2 + 1-ａｘ ,其中ａ>0 .(1)解不等式 ｆ(ｘ) ≤ 1;(2 )略 .分析　不等式 ｆ(ｘ)≤ 1,即 ｘ2 + 1≤ …     

关于多元复相系稳定平衡条件的推证

从熵判据出发,对多元复相系的稳定平衡条件进行了详细的推证,给出了多元复相系的稳定平衡条件:CV>0,PV<0,∑li=1∑lj=1μiNδΝjδΝi>0,并对稳定平衡条件的物理意义作了说明.     

不定积分运算性质的代数解释

关于不定积分,有两个问题是不容易解释的: 1.∫af(x)b=a∫f(x)dx成立的条件是a为常数且a≠0,可是在许多教材的证明中并没有用到a≠0这个条件。对此有一种解办法,也有在证明中用到a≠0这个条件的。 2.不定积分“移项”后有时要添上一个任意常数C。例如:     

恒定电流和连续电流的充要条件

本文指出,将(?)·j=0作为电流的恒定条件是不准确的;并对电流的恒定条件和连续条件进行了分析.最后利用这两个条件讨论一些电流.     

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.