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1.
用壳寡糖分别与硝酸铕和硝酸铽反应, 制备了壳寡糖-铕、壳寡糖-铽两种配合物. 用红外光谱、紫外光谱、 荧光和X射线光电子能谱(XPS)等分析测试手段对配合物进行了表征. 以吩嗪硫酸甲酯(PMS)-还原型辅酶Ⅰ烟酰胺腺嘌呤二核苷酸(NADH)-硝基四氮唑蓝(NBT)产生超氧阴离子自由基(·O-2)来研究壳寡糖和壳寡糖稀土金属配合物对·O-2自由基的清除作用. 结果表明: 壳寡糖与Eu3 或Tb3 形成了配合物, 壳寡糖-铕、壳寡糖-铽配合物中不仅壳寡糖氨基上的N原子参与了配位, 同时仲羟基的O原子也参与了配位. 壳寡糖和壳寡糖稀土金属配合物对·O-2均具有明显的清除作用, 配合物与壳寡糖相比对·O-2具有更高的清除活性.  相似文献   

2.
用N-亚甲基磷酸化壳寡糖(NMCP)与La(NO3)3反应,制备了N-亚甲基磷酸化壳寡糖与镧的配合物(NMCP-La)。用红外光谱(IR)、热重分析仪(TG)等分析手段对配合物进行了表征。讨论了溶液的酸碱度、反应时间和物料比对配合物形成的影响。结果表明,当pH为4,物料比为1∶1,反应时间控制为10 min时,产物中镧的含量较高,耗能较小。N-亚甲基磷酸化壳寡糖上的-P-OH参与了与镧的配位,配位数是八。  相似文献   

3.
用壳寡糖与硝酸钕反应,制备了壳寡糖-钕配合物。用红外光谱和X射线光电子能谱等分析测试手段对配合物进行了表征。从IR和XPS的测试结果可知,Nd^3+与壳寡糖上的氨基N和仲羟基O配位,形成壳寡糖-钕配位聚合物。通过电导率研究其配位数,发现Nd^3+可与壳寡糖的4个链节单元配位.根据以上的实验可推定中心离子Nd^3+与壳寡糖4个链节单元上的氨基N和仲羟基O结合,形成八配位的壳寡糖-钕配位聚合物。  相似文献   

4.
用壳寡糖分别与硝酸铕和硝酸铽反应,制备了壳寡糖-铕、壳寡糖-铽两种配合物。用红外光谱、紫外光谱、荧光和X射线光电子能谱(XPS)等分析测试手段对配合物进行了表征。以吩嗪硫酸甲酯(PMS)-还原型辅酶Ⅰ烟酰胺腺嘌呤二核苷酸(NADH)-硝基四氮唑蓝(NBT)产生超氧阴离子自由基(·O2^-)来研究壳寡糖和壳寡糖稀土金属配合物对·O2^-自由基的清除作用。结果表明:壳寡糖与Eu^3+或Tb^3+形成了配合物,壳寡糖-铕、壳寡糖-铽配合物中不仅壳寡糖氨基上的N原子参与了配位,同时仲羟基的O原子也参与了配位。壳寡糖和壳寡糖稀土金属配合物对·O2^-均具有明显的清除作用,配合物与壳寡糖相比对·O2^-具有更高的清除活性。  相似文献   

5.
以壳寡糖(COS)为配位体,锌(Ⅱ)离子为配位离子,在均相反应条件下合成了壳寡糖锌(Ⅱ)配合物(COS-Zn),并优化了配合物的合成条件.利用红外光谱法(FT-IR)、差热分析法(DTA)和元素分析(EA)进行结构表征,并对配位机理进行了初步探讨.  相似文献   

6.
纳米壳寡糖-铁配合物的制备及其生物活性的研究   总被引:7,自引:0,他引:7  
黄进  汪世龙  孙晓宇  张蕤  姚思德 《化学学报》2006,64(15):1570-1574
用分子量为5000的壳寡糖与FeCl3反应制得纳米壳寡糖-铁配合物, 并通过FTIR, UV, DTA, TEM, PCS等手段对其结构与形态进行了表征. 同时用紫外光谱法和凝胶电泳法对纳米壳寡糖以及纳米壳寡糖-铁配合物的生物活性进行了研究, 实验结果表明纳米壳寡糖-铁配合物是以静电嵌插的方式与质粒DNA进行结合, 而致使DNA损伤.  相似文献   

7.
壳寡糖与镧、铈配合物的合成、表征及应用   总被引:7,自引:0,他引:7  
合成了壳寡糖,镧和壳寡糖,铈配合物,用红外光谱和紫外光谱进行了表征,并证实了氮,金属(N-M)键的形成,元素分析证实配合物中各元素C:H:N:La或Ce的原子个数比分别接近于24:44:4:1,即相当于配位数为4。壳寡糖一镧和壳寡糖一铈较未配位的镧或铈具有更强的催化氧化能力。配合物除去废液中磷[(PO)^3-4]的效果比未配位的镧和铈提高10%。配合物可提高蔬菜、水稻种子的发芽率,促进作物的营养生长,提高水稻产量3,3%,提高黄瓜产量12%~15%,对十字花科蔬菜的病毒有一定的抑制作用。  相似文献   

8.
李小芳  宋正月  冯小强  杨声 《化学通报》2013,(12):1145-1148
制备了不同摩尔比的羧甲基壳聚糖-铜配合物,运用红外光谱、紫外吸收光谱、循环伏安法、差热-热重分析等手段对配合物进行了结构性能表征。结果表明,羧甲基壳聚糖中的羧基和氨基参与了与Cu2+的配位,生成的羧甲基壳聚糖-铜配合物具有电化学活性,其热稳定性较羧甲基壳聚糖降低。  相似文献   

9.
用壳寡糖及酰化壳寡糖与氯化钕反应,合成了壳寡糖-钕和酰化壳寡糖-钕配合物,利用红外光谱(IR)、紫外光谱(UV)手段对其结构进行了表征。在模拟生理条件下,本文采用紫外光谱和荧光光谱研究了两种配合物与牛血清白蛋白(BSA)的相互作用,计算了配合物与BSA的结合常数、结合位点数。荧光光谱结果表明,配合物均可有规律地猝灭BSA的内源荧光,猝灭方式为静态猝灭,壳寡糖-钕和酰化壳寡糖-钕分别与BSA的结合常数为1.33×104L·mol-1和6.95×104L·mol-1,结合位点数为1.05和1.3,说明配合物与BSA均具有较强的结合作用,能够被BSA储存和运输,并且酰化壳寡糖-钕与BSA的结合能力强于壳寡糖-钕。最后采用紫外光谱法对其作用机理进一步确认。因此,酰化壳寡糖-钕可以被BSA存储和运输,有望成为蛋白质荧光探针。  相似文献   

10.
将芹菜素(AP)与钆(III)离子配位生成配合物,以期提高芹菜素抗高尿酸血症活性。以具有一定抗炎、抗痛风活性的芹菜素为配体,以稀土金属钆(III)离子为配位中心,设计合成芹菜素-钆配合物(AP-Gd)。采用紫外(UV)、红外(IR)、氢核磁共振(~1H-NMR)、电导法、 X射线光电子能谱(XPS)、差热-热重分析(TG-DTA)等技术对配合物的化学结构进行表征。考察配合物对酵母浸粉联合氧嗪酸钾诱导的高尿酸血症小鼠模型中尿酸、黄嘌呤氧化酶及超氧阴离子水平的影响。结果表明:芹菜素与钆(III)离子配位生成了配合物,配合物组成式为:[Gd(C_(15)H_9O_5)_2]·NO_3·3H_2O。芹菜素A环的5-OH和C环的4位C=O与钆(III)离子形成了配合物,且芹菜素与钆(III)离子的配位比为2。抗高尿酸症活性研究发现,芹菜素-钆配合物对高尿酸血症小鼠黄嘌呤氧化酶的抑制作用、清除超氧阴离子能力、降低血清尿酸水平及促进尿酸排泄能力均优于芹菜素,提示芹菜素与钆(III)离子配位后,所得配合物抗高尿酸血症活性增强。  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.
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   

13.
14.
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   

15.
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989.  相似文献   

16.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

17.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

18.
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   

19.
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   

20.
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   

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