沙林酸印迹聚邻苯二胺纳米膜制备及结构表征

采用电化学聚合法合成了对有机磷毒剂沙林具有特异识别的聚邻苯二胺(PPD)分子印迹纳米膜(iPPD).利用石英晶体微天平(QCM)证实了印迹效应的存在，并用循环伏安法(CV)、AFM、XPS进行了系统的结构表征.结果表明，分子印迹膜的膜厚约20 nm，膜的表面呈“石林”状，疏松多孔，具有良好的吸附性能.分子印迹主要影响聚合物的三维排列，而聚合物的化学组成没有发生改变.该种分子印迹纳米膜在选择性检测军用毒剂沙林中具有良好的应用前景.     

分子烙印传感器的研究进展

分子烙印技术是制备具有选择性分子识别能力的聚合物的新兴技术,其应用之一是将分子烙印聚合物用作分析化学中化学传感器的识别元件。本文综述了分子烙印技术的原理方法及其在传感器方面的应用,评述了分子烙印传感器的发展方向,展望了其在有机磷化合物检测中的应用前景。     

分子烙印聚合物固定相分离咖啡因和茶碱的研究

分子烙印是一种新兴的分子识别技术,利用该技术可制备对烙印分子具有“预定”识别能力的高分子聚合物,即分子烙印聚合物（MIP）,从而可以对性质和组成相近的组如对映体等进行分离^[1,2],咖啡因与茶碱的分子烙印聚合物的制备以及二者分析已有报道^[3-9],但存在两种完全相反的结论。一种观点认为,即使以咖啡因为烙印分子,所制备的聚合物对咖啡因分子的选择性吸附能力也小于茶碱^[3-6]。而另一种观点则认为,在一定条件下,如以咖啡因分子为烙印分子的烙印聚合物对咖啡因分子具有更强的吸附能力^[7-9]。本文分别采用茶碱和咖啡因作为烙印分子,以甲基丙烯酸等为功能单体,在不同条件下制备了多种非共价型分子烙印聚合物,并系统地考察了其作 为HPLC固定相对咖啡因和茶碱的分离能力,同时也对烙印分子应具备的条件加以探讨。     

硅胶键合型奎宁分子烙印聚合物的合成及性能

硅胶键合型奎宁分子烙印聚合物的合成及性能;微孔硅胶;分子烙印聚合物;自组装;平衡吸附实验     

分子烙印聚合物作超临界流体萃取后处理用固体吸附剂

利用离线超临界流体萃取与高效毛细管电泳相结合，分析了标准添加样品中的除草剂（2，4－二氯苯氧乙酸（2，4－D）），探讨了温度、压力和改性剂对萃取的影响，考察了在不同条件下合成的2，4－D为烙印分子的子烙印聚合物对2，4－D在不同极性溶剂中的吸附能力，并将分子烙印聚合物作为超临界流流体萃取后处理用固体吸附剂，结果表明，在甲醇和水的混合极性溶剂中制备的分子烙印聚合物对提高分析选择性的效果最佳。     

司它夫定分子烙印聚合物对模板分子的烙印效果研究

以抗爱滋病药物司它夫定为模板分子,甲基丙烯酸为功能单体,二甲基丙烯酸乙二醇酯为交联剂,用本体聚合法制备了分子烙印聚合物.本文考察了不同聚合条件和不同的单体与模板分子物料配比对产物分子烙印聚合物的吸附性能的影响.     

有机磷神经毒剂分子印迹聚合物的模拟模板分子

采用DFT/B3LYP-D3(BJ)/6-31G(d,p)计算模拟方法分析探讨了双(对硝基苯基)磷酸酯(BNPP)替代对氧磷(PO)用作有机磷神经毒剂分子印迹聚合物(MIPs)模板分子模拟物的可行性. 通过对比BNPP和PO两种模板分子分别与各种功能单体形成的复合物的构型稳定性和结合能大小, 确认了以4-甲基丙烯酰胺基安替比林(MAAP)为第一功能单体、 甲基丙烯酸(MAA)为第二功能单体组成的双功能单体体系是最佳功能单体体系. 以BNPP为模板分子、 MAAP-MAA为单体体系、 乙二醇二甲基丙烯酸酯(EGDMA)为交联剂、 纳米二氧化硅为载体, 采用表面印迹技术制备了SiO₂@BNPP分子印迹聚合物, 并对聚合物的表面形貌和吸附性能进行了分析. 实验结果表明, 当n(BNPP)/n(MAAP)/n(MAA)/n(EGDMA)为1∶1∶4∶20时, MIPs的吸附容量最大可达19.03 mg/g, 对4-硝基苯酚(4-NP)的分离因子为17.50; MIPs能够快速吸附模板分子, 5 min即可达到吸附平衡量的92%, 动态吸附平衡时间仅为15 min, 重复使用5次后仍能保持良好的吸附能力; 吸附过程符合准二级动力学模型和Langmuir等温吸附模型, Scatchard方程分析表明MIPs中存在两类吸附作用位点. 实验结果与计算模拟结果的一致性表明, 计算模拟对有机磷神经毒剂MIPs的设计和研究具有一定的指导意义.     

分子印迹纳米膜的制备及其在检测神经性毒剂沙林中的应用

采用电化学聚合法首次合成了对有机磷毒剂沙林有快速响应和高灵敏度的分子印迹纳米膜。用压电晶体频移法测出其膜厚约为35nm，对影响电聚合反应的因素(如模板分子浓度、单体浓度、扫描电位和扫描次数)进行了筛选，进而在石英晶体微天平(QCM)上制成了纳米分子印迹传感器。这种新型传感器响应速度快(最初响应时间2s)，抗干扰能力强，检测范围宽(O．7～50μL/L)，灵敏度高(1nL/L)。     

以桑色素为模板的分子烙印聚合物的制备、结合特性及其在薄层色谱固定相方面的应用

以桑色素为模板,选用不同的功能单体和致孔剂制备了一系列分子烙印聚合物,采用结合实验考察了它们对底物的吸附特性,发现以丙烯酰胺为功能单体,以乙酸乙酯为致孔剂制得的烙印聚合物对底物有很好的选择性,同时对一些结构相似的化合物具有一定的结合力.Scatchard方程研究结果表明,在研究的浓度范围内聚合物形成了一类等价的结合位点,其平衡离解常数为0.877mmol/L,对模板分子的最大表观结合量为59.18μmol/g.可认为桑色素分子中3,7,4'位的羟基与功能单体的氢键作用是分子烙印聚合物具有底物选择性的主要因素.以该分子烙印聚合物为薄层色谱固定相,可以把模板分子从结构相似的化合物中分离出来,最小分离度为1.19.     

烟碱分子烙印聚合物的吸附特性

利用分子烙印技术，以烟碱为烙印分子，甲基丙烯酸(MAA)为功能单体，乙二醇二甲基丙烯酸酯(EDMA)为交联剂，合成了对烟碱具有特异性作用的分子烙印聚合物P(Nic)；通过平衡吸附实验，评价了其对烟碱的亲和力和选择性。与非烙印聚合物相比，P(Nic)对烟碱表现了很高的亲和力；Scatchard分析表明在P(Nic)中存在对烟碱有不同的亲和力的两类作用位点。通过与氨基吡啶类物质在P(Nic)上的吸附行为比较，表明P(Nic)对烟碱具有很好的选择性。本工作证明了用P(Nic)作为固相萃取(SPE)材料选择性地从烟草烟雾中提取烟碱的可能性。     

非那雄胺合成工艺改进

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。     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

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.     

氯氧化镁生成热的研究

用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。     

Acid hydrolysis of carboxymethylcellulose of low degree of substitution

Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position.     

Mechanism of action of base-catalyzed oxygenation of phenol derivatives

Cyclopropyl derivative of 2,6-di-tert-butylphenol is synthesized as a probe to investigate the mechanism of base-catalyzed autooxidation of phenol derivatives. Our study indicates that one electron reduction of molecular oxygen from phenolate gives phenoxyl radical 3, a key intermediate of autooxidation. The coupling of phenoxyl radical and superoxide radical gives peroxylate anion 4 and produces the final epoxy alcohol adduct 6.     

Estimation of Kinetic Parameters of Thermal Oxidation of Ilmenite

The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of hematite Fe₂O₃. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the best fitting experimental data. This revised version was published online in August 2006 with corrections to the Cover Date.     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

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.

     

化学计量中不确定度评定研究进展

测量不确定度是表征合理地赋予被测量之值的分散性的参数。本文针对化学计量不确定度评定基础模型仅适用于线性模型、概率分布为正态分布或缩放位移t分布等局限,介绍了近年来不确定度评定的研究热点:蒙特卡罗方法(Monte Carlo Method,MCM),不确定度评定的来源、评定概念、评估方法及其发展过程,扩大了测量不确定度评定与表示的适用范围。     

微量钙的测定方法研究进展

介绍了1995-2006年期间测定微量和痕量钙的方法,如电感耦合等离子体-原子发射光谱法、原子吸收光谱法以及离子色谱法等的工作原理和特点,并说明了其测定微量钙的应用领域。并对微量钙的测定技术进行了展望(引用文献55篇)。     

Stages of thermal decomposition of sodium oxo-salts of sulphur

Thermal behaviour of sodium oxo-salts of sulphur: Na₂SO₄, Na₂S₂O₇, Na₂S₂O₆, Na₂SO₃, Na₂S₂O₅, Na₂S₂O₄, Na₂S₂O₃, Na₂S₃O₆ and of sulphides Na₂S and Na₂S₂ was studied on heating up to 1000°C. The experiments were performed with anhydrous compounds obtained from commercial products by recrystallisation and dehydration. The stage mechanisms of decomposition of anionic sub-lattices of the salts have been proposed basing on the Górski’s morphological classification of simple species. The thermal stability and the stage decomposition mechanisms were correlated with the structure and the potential chemical properties of the salt anions. The thermal decomposition processes were studied by means of thermal analysis, and the decomposition products were identified by means of X-ray phase analysis.