偶氮氯膦Ⅲ比色法测定药品钙     

吴春生  丁大永 《淮北职业技术学院学报》2003,2(4):92-93

在PH 6.6的磷酸二氢钾——氢氧化钠的缓冲溶液中,研究了偶氮氯膦Ⅲ(CPA Ⅲ)与钙的络合显色反应,建立了药品钙测定的新方法。该法线性范围为0～30μg/25ml,r=0.9997,回收率95.4％～97.4％,RSD=0.158％～0.693％。方法简便、快速、准确可靠。  相似文献   

3，5—二溴—4—氨基苯在荧光酮离解作用的研究和离解常数的测定     

黄应平  颜克美 《荆州师专学报》1994,17(2):57-60

本文详细研究了新显色剂3，5-二溴苯基荧光酮的离解性质，利用光度法测定其离解常数pk1,pk2,pk3,pk4分别为1.85,5.42,10.51,12.44。与苯基荧光酮试剂比较，该试剂分子引入溴吸电子基团，使试剂的酸性增强，金属离子显色反应灵敏度、选择性有很大的提高。  相似文献   

过渡金属化合物催化格氏试剂反应     

冯桂荣 《唐山师范学院学报》2001,23(5):27-30

简述了近十年来用过渡金属配合物（如钯、铜、镍、锆、铁、钛）作催化剂，通过格氏试剂反应进行立体选择性合成的方法和原理。  相似文献   

高职公共英语“四三”制分层教学模式的探讨     

吴玉光 《教育与职业》2011,(20)

分层教学是因材施教原则在高职教育教学中的灵活运用,是高职院校公共英语教学改革的一大特色。文章在总结前人研究的基础上,结合湖南商务职业技术学院英语教学改革的具体情况,提出四三制英语分层教学模式,并探讨其成效和不足,为进一步开展分层教学提供一些有益的借鉴和建议。  相似文献   

Results on energies for trees with a given diameter having perfect matching     

王文环  康丽英 《上海大学学报(英文版)》2011,15(6):493-500

Let Γd2nbe the set of trees with a given diameter d having a perfect matching,where 2n is the number of vertex.For a tree T in Γd2n,let Pd+1be a diameter of T and q = d m,where m is the number of the edges of perfect matching inPd+1.It can be found that the trees with minimal energy in Γd2nfor four cases q = d 2,d 3,d 4,[d2],and two remarks aregiven about the trees with minimal energy in Γd2nfor2d 33q d 5 and [d2] + 1 q2d 33 1.  相似文献   

meso-四-(4-苯基)卟啉与铜(Ⅱ)显色反应的分光光度研究   总被引：6，自引：0，他引：6  

周连文  陈玉婷  李新民  刘红英 《德州学院学报》2003,19(2):62-64

研究了在Tween - 80存在下 ,meso -四 - ( 4-苯基 )卟啉与铜的显色反应 .络合物的最大吸收波长为 416nm ,表观摩尔吸光系数为 3 .75× 10 5L·mol-1·cm-1.铜含量在 0～ 1.6 μg/ 10mL范围内符合比尔定律 .络合物的组成为铜 (Ⅱ ) :TPP =1:1,本法已应用于环境水样中痕量铜的测定 ,结果满意 .  相似文献   

Active changes of lignification-related enzymes in pepper response to Glomus intraradices and/or Phytophthora capsici     

郑虎哲崔春兰  张玉廷王丹  荆宇KIM Kil Yong 《Journal of Zhejiang University. Science. B》2005,6(8):778-786

INTRODUCTION Plants have defense mechanisms against patho-gen infection by inducing systemic resistance in re-sponse to localized pretreatment with biological cotrol agents, thus making them resistant to subsequpathogen infection (Caruso et al., 1999; Hammschmidt, 1999; Mohammadi and Kazemi, 2002; yada et al., 1995; Pozo et al., 2002; Ray et al., 199Biological control of plant pathogens has receivmuch more attention. It is well known that plants amicroorganisms symbiosis is a defense m…  相似文献   

表面活性剂增敏分光光度法测定微量锡研究     

冯刚柏苗  朱霞石 《科学文化评论》2007,24(6):1059-1062

建立了表面活性剂增敏分光光度法测定水样中微量锡的新方法。锡与二甲酚橙形成络合物,在pH9.5时吸光度A最大,加入聚乙二醇辛基苯基醚（TritonX-100）胶束后,络合物的稳定性好,灵敏度大大增加。实验条件下显色络合物的最大吸收峰位于431nm处,线性范围为Sn2.0—20.0μg/mL,回收率为98.9%—104.2%。此方法选择性好、灵敏度高、操作简单,用于分析水样中的微量锡,结果令人满意。  相似文献   

Microwave-assisted synthesis, anticonvulsant activity and quantum mechanical modelling of N-（4-bromo-3-methylphenyl） semicarbazones     

Shalini M  Yogeeswari P  Sriram D  Induja S 《Journal of Zhejiang University. Science. B》2007,8(1):45-55

Objective： To study the effect of halo substitution on disubstituted aryl semicarbazones on the anticonvulsant potential and model the activity based on quantum mechanics. Methods： A series of twenty-six compounds of N^4-（4-bromo-3-methylphenyl） semicarbazones were synthesized and evaluated for the anticonvulsant activity in the maximal electroshock seizure （MES） and subcutaneous pentylenetetrazole （scPTZ） seizure threshold tests. Some potential compounds were also tested in the subcutaneous strychnine （scSTY） and subcutaneous picrotoxin （scPIC） seizure threshold tests. The synthesized compounds were tested for behavioral impairment and CNS （central nervous system） depression in mice. Quantum mechanical modelling was carried out on these compounds to gain understanding on the structural features essential for activity. Results： Some compounds possessed broad spectrum anticonvulsant activity as indicated by their effect in pentylenetetrazole, strychnine, picrotoxin and maximal electroshock seizures models in resemblance to other aryl semicarbazone derivatives reported earlier. The higher the difference in HOMO （highest occupied molecular orbital） and LUMO （lowest unoccupied molecular orbital） energy levels was, the greater was the activity profile. Conclusion： The pharmacophoric requirements for compounds to exhibit anticonvulsant activity that includes one aryl unit in proximity to a hydrogen donor-acceptor domain and an electron donor have been justified with the molecular orbital surface analysis of the synthesized compounds.  相似文献   

非甾类抗炎剂3—氨基—1—（间—三氟甲基苯基）—2—吡唑啉的合成     

陈邦银  王奕 《科技通报》1990,6(5):300-300

英国Wellcome实验室Higgs等人于1979年报道了3～氨基-1-(间-三氟甲基苯基)-2-吡唑啉(BW 755 C)对于大鼠的抗炎活性,提出该化合物是通过抑制CO和LO途径发挥抗炎作用,活性较消炎痛强。虽然后来在临床试验中发现有一定毒性限制了进一步在临床上的应用,但是它作为一个双重抑制剂仍然具有一定的理论意义和实际意义,并且可能进行结构修饰找到毒性更小、抗炎活性更强的抗炎剂。本文按下列合成路线制备BW 755 C及其盐酸盐。  相似文献