首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
本文用伏安法对药物中的维生素B6(VB6)进书测定。在0.05mol/L(CH3)4NBr-(CH3)4NOH底液中(pH-6.0~11.0),VB6在-1.88V(VS,SCE)产生一灵敏还原峰,峰高与VB6浓度在8.0×10-7~2.2×10-5mol/L范围内成线性关系,检测下限为2.0×-7mol/L,用本法,可直接测定药物中VB6的含量。  相似文献   

2.
本文研究了铅(Ⅱ)-胱氨酸-甘氨酸体系在悬汞电极上的吸附伏安特性。在0.001mol/L甘氨酸溶液中(pH=8.2),加入铅(Ⅱ)溶液后,使胱氨酸的峰电流增大,最佳实验条件下,该峰电流与优氨酸浓度在3.3×10-8~1.0×10-6mol/L范围内呈良好的线性关系,检测限过3.3×10-9mol/L。通过对该峰的性质及反应机理的研究,证明此峰为配合物吸附还原峰,吸附反应物为铅(Ⅱ)与胱氨酸形成的1:1配合物,电机反应为二电子还原。  相似文献   

3.
以镍(Ⅱ)-四氮杂轮烯大环配合物为载体,制备了一种新型PVC膜碘离子化学传感器.研究结果表明,该传感器对碘离子的线性响应范围为3.0×10-6~1.0×10-1mol·L-1,响应斜率为57.3±0.3mV·dec-1.该传感器具有良好的重视性和选择性.  相似文献   

4.
在NH3-NH4Cl缓冲溶液(pH=9.5)中,吲哚乙酸与磷钨杂多酸的还原产物在滴汞电极上于-1.70V(vs.SCE)处产生一灵敏的极谱波,该波波高与吲哚乙酸在1.0×10-7~4.0×10-7mol/L范围内成线性关系,检出限为50×10-8mol/L。加标回收实验5次,测定结果的平均回收率为99.7%,RSD为1.09%.  相似文献   

5.
在系统地研究Eu(Ⅲ)-La(Ⅲ)-TC协同荧光增敏体系的基础上,提出了一个测定微量四环素的荧光分析新方法.体系的激发波长和发射波长分别为396nm和616nm,线性范围为2×10-9~4×10-7mol·L-1.该法能用于测定尿液和血浆中的微量四环素.  相似文献   

6.
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).  相似文献   

7.
美洛昔康在HCl底液中的单扫示波极谱法测定   总被引:1,自引:0,他引:1  
在0.05MHCl(pH=1.70)底液中,用单扫示波极谱法可以得到一个灵敏的美洛昔康导数还原峰,其峰电位为Ep=-1.05V(vs.SCE).导数峰电流与美洛昔康浓度在1×10-7mol/L~9×10-6mol/L(其线性相关系数r = 0.9992)范围内呈现良好的线性关系,美洛昔康的检出限可达 5.0×10-8mol/ L.该法可用于模拟尿样的测定.  相似文献   

8.
单扫描示波极谱法测定非诺贝特的研究   总被引:1,自引:0,他引:1  
非诺贝特在pH6 37的Britton Robinson缓冲溶液中 ,于 - 1 2 5V产生一灵敏的极谱还原峰 ,峰电流与非诺贝特浓度在 1.0× 10 -4~ 9.0× 10 -4g/L范围内有良好的线性关系 ,检测下限为 5 .0× 10 -5g/L。  相似文献   

9.
在pH=8.89,NH3·H2O—NH4Cl底液中,用单扫描示波极谱法,进行常规极谱测定,锌在-1.33V(vs.SCE)产生一尖锐灵敏的极谱波,峰电流与锌的浓度在2.0×10-6mol·L-1~7.0×10-4mol·L-1范围内呈良好的线性关系,检出限为1.0×10-6mol·L-1.线性回归方程为Ip=18.12x+226.5,x为锌的浓度,相关系数r=0.9991。测定金施尔康中锌的标准加入回收率可达98.8%~101.1%,结果令人满意。  相似文献   

10.
报道了一种灵敏测定盐酸克林霉素的电化学方法。在0.1mol·L-1甘氨酸-氯化钠-氢氧化钠介质中,盐酸克林霉素产生一灵敏的吸附波,峰电流(Ep=-1.35V/vs.Ag-AgCl电极)与其浓度在2×10-7~4×10-5mol·L-1范围呈线性关系。利用本法对原料药及胶囊剂样品含量进行了测定,获满意结果。  相似文献   

11.
汉字倒说     
汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。  相似文献   

12.
《海外英语》2007,(5):44-45
It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,  相似文献   

13.
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/  相似文献   

14.
《海外英语》2007,(5):10-11
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?  相似文献   

15.
钱生钱!     
我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了  相似文献   

16.
《海外英语》2007,(4):36
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.  相似文献   

17.
The problem on the geometrc inequalities involving an n-dimensional simplex and its inscribed simplex is studied. Aninequality is established, which reveals that the difference between the squared circumradius of the n-dimensional simplex andthe squared distance between its circumcenter and barycenter times the squared circumradius of its inscribed simplex is not lessthan the 2(n-1)th power of n times its squared inradius, and is equal to when the simplex is regular and its inscribed siplex is atangent point one. Deduction from this inequality reaches a generalization of n-dimensional Euler inequality indicating that thecircumradius of the simplex is not less than the n-fold inradius. Another inequality is derived to present the relationship betweenthe circumradius of the n-dimensional simplex and the circumradius and inradius of its pedal simplex.  相似文献   

18.
王菲 《华章》2007,(12):273-273
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.  相似文献   

19.
现在,我们可以没有面包,没有钱,没有房子,没有车子……但我们唯独不能丢失的是高尚的情操,笃定的信念,还有,满满的希望!  相似文献   

20.
Using virtual reality for interactive design gives a designer an intuitive vision of a design and allows the designer to achieve a viable, optimal solution in a timely manner. The article discusses the process of making the Virtual Reality System of the Humble Administrator's Garden. Translating building data to the Virtual Reality Modeling Language (VRML) is by far unsatisfactory. This creates a challenge for computer designers to do optimization to meet requirements. Five different approaches to optimize models have been presented in this paper. The other methods are to optimize VRML and to reduce the file size. This is done by keeping polygon counts to a minimum and by applying such techniques as object culling and level-ofdetail switching.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号