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1.
介绍了聚(N,N-二甲基苯胺)阳离子自由基的结构特点,利用顺磁共振波谱和紫外-可见吸收光谱,研究了温度及溶液粘度对聚合物自由基的影响,发现聚(N,N-二甲基苯胺)的主,侧链结构构象变化与其自由基的稳定性很大的关系。  相似文献   

2.
详细报道了Nafion-聚[N′,N″-(1,3-丙二亚甲基)双(1,2-苯二氨基)-N,N′,N″,N]合镍[PolyNi(Ⅱ)L]修饰微铂电极的制备及性质.实验表明,该修饰电极对NO有较高的灵敏度和选择性.当NO的浓度在2.0×10-7~1.6×10-5mol/L范围内峰电流与NO的浓度呈线性关系,相关系数r=0.994.用于血液中NO的检测,效果良好.  相似文献   

3.
张爱梅  王怀生 《分析化学》1996,24(3):292-295
本文基于NO2^-对KBrO3氧化酸性间胺黄而使其褪色的催化作用,以及NO3^-经锌粉还原为NO2^-,建立了灵敏的催化光度测定痕量NO2^-、NO3^-的新方法,并讨论了其动力学条件,测定范围10-90μg/L,方法简便快速、选择性好,用于水及食品中痕量NO2^-、NO3^-的测定,结果满意。  相似文献   

4.
N,N-二甲基对甲苯胺引发N-对甲苯基马来酰亚胺光聚合的引发机理叶克强,董建华,丘坤元,冯新德(北京大学化学系,北京,100871)关键词光引发聚合机理,电荷转移复合物,激基复合物,荧光淬灭,N,N-二甲基对甲苯胺,N-对甲苯基马来酰亚胺N,N-二甲...  相似文献   

5.
合成了两种新的N,N,N’,N”,N”-五苯并咪唑甲基二乙三胺VO(Ⅱ)多核配合物并进行了元素分析,IR,UV-visESR等表征。求得了配合物的自旋Hamilton参数,两配合物中V(Ⅳ)的电子环境差别较大。体外抗癌活性和农药活性测定结果表明配合物具有一定生物活性。  相似文献   

6.
ANEW.NEO-CLERODANEDITERPENEFROMAJUGANIPPONENSIS¥ZhunLIU,ZhongQinLI,ChunXingZHANG,RuYuCHEN(TheInstituteofElemento-organicChemi...  相似文献   

7.
报道了用1,3-丙二醇二对甲苯磺酸酯和N,N′,N″,N-四(对甲苯磺酰基)三乙撑四胺经环化、硫酸水解等步骤合成1,4,7,10-四氮杂环十三烷的新途径  相似文献   

8.
在无水乙醇中,1-亚硝基-2萘酚同N,N'-1,4-亚丁基双[2,3,3-三甲基-3H-吲哚]溴化物反应制得N,N'-亚丁基双[螺吲哚啉萘并嗪],经IR,UV, ̄1HNMR和元素分析确认了结构,并对其光致变色性能进行了初步的考察。  相似文献   

9.
樟脑酮作齿科材料的可见光固化引发体系   总被引:3,自引:0,他引:3  
研究了可见光引发樟脑酮和樟脑酮/N,N-二甲基对甲基苯胺复合体系的聚合反应,单一樟脑酮体系通过氢转移反应可有效地发烯类单体的聚合反应,樟脑酮/N,N-二甲基对甲基苯胺复合体系可使聚合反应速度加快和大大缩短达到最大转化率所需时间,同时樟脑酮/N,N-二甲基对甲基苯胺复合体系具有良好的抗氧阻聚能力,在氧存在下,聚合反应的诱导期明显地低于单一樟脑酮体系,在口腔温度和有氧条件下,樟脑酮/N,N-二甲基对四  相似文献   

10.
聚N-烷基丙烯酰胺类凝胶及其温敏特性   总被引:11,自引:0,他引:11  
研制成功5种聚N-烷基丙烯酰胺类温敏凝胶:聚N-异丙基丙烯酰胺(PNIPA),聚N-异丙基丙烯酰胺+甲基丙烯酰胺(PNIPA/MAA),聚N,N-二乙基丙烯酰胺(PNDEA),聚N-正丙基丙烯酰胺(PNNPA),聚N,N-二乙基丙烯酰胺+N-叔丁基丙烯酰胺(PNDEA/NTBA),并系统研究了这些凝胶的温敏相交特性.以聚N-异丙基丙烯酰胺(PNIPA)凝胶相交特性为基础的凝胶萃取过程对牛血清白蛋白和兰葡聚糖溶液的浓缩实验表明,凝胶萃取对于浓缩和制备贵重生化制品是很有效的.  相似文献   

11.
利用手持技术改进测定乙醇分子结构实验   总被引:1,自引:0,他引:1  
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。  相似文献   

12.
13.
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988.  相似文献   

14.
实验教学目的是从解决实际问题出发,以实验技术训练和实验设计思想培养为目标。介绍了将单一的物质分配系数测定实验改进为综合实验,提高了实验效果及实验资源利用率。  相似文献   

15.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

16.
Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases.  相似文献   

17.
18.
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.  相似文献   

19.
由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。  相似文献   

20.
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