统计模拟分光光度法测定复方消咳新片组分含量

用统计模拟分光光度法测定复方消咳新片４个组分含量。按均匀设计表制备合成样品，绘制溶液的ＵＶ－ＶＩＳ吸收曲线，获得有限但足够的实验数据，用逐步回归法构造反映该复方制剂组分在灵敏波长的吸光度－组分含量经验关系的“最优”数学模型，用改进单纯形法寻优，求出未知样品的各组分含量。磺胺甲基异恶唑、甲氧苄胺嘧啶、盐酸溴已新、枸橼酸维静宁的回收率分别为１００３％、１００４％、９９９％、９９０％，标准差分别为０９１％、１４％、１２％、３９％。     

A ONE-STEP SURFACE MODIFICATION PROCEDURE TO PEG-GRAFTED NANO-TITANIA

PEG （Polyethylene Glycol）-grafted nano-titania has been obtained in a one-step procedure using hexamethylene diisocyanate as the coupling agent and dibutyltin dilaurate as the catalyst in toluene at 80℃ and characterized qualitatively by FTIR and quantitatively by elemental analysis and thermogravimetric analysis. A comparison of nano-titania with two other commonly used inorganic nanoparticles, nano-silica and nano-alumina, is made, revealing that reactivity order is nano- silica 〉 nano-alumina 〉 nano-titania in view of PEG grafting. Possible mechanism of PEG grafting is also discussed.     

Synthesis of molecular sieve AlPO4-12

A member of the novel family of crystalline microporous aluminophosphates, AlPO₄-12, was synthesized by hydrothermal crystallization using different aluminum-containing compounds. Three new crystalline phases were obtained by varying the composition of the reaction mixture. The effect of the synthesis conditions on the hudrothermal process and the kinetics of crystallization are discussed. The apparent activation energies obtained for AlPO₄-12 are 20.9 and 14.6 kcal/mol for nucleation and crystallization, respectively. The adsorption isotherms of one AlPO₄-12 product were measured.     

Cl/Ag体系研究 Ⅱ.Cl吸附引起的表面结构变化

运用LEED,UPS和HREELS等表面技术研究了氯吸附至(c)阶段的Ag(111)表面结构.结果表明,表面上有三维的AgCl(111)生成,其生长按修正的Stranski-Krastanov模式进行.伴随着AgCI(111)生长的同时,表面上产生缺陷.这种缺陷只有在氯吸附至(c)阶段时表面上形成三维AgCI的过程中才能产生,它一旦在表面上形成后,表面上氯的存在与否对其不产生影响.本文提出了一个(c)阶段时的Cl/Ag(111)体系的结构模型.     

氨基羧酸纤维分离富集-电感耦合等离子体原子发射光谱法测定多种痕量稀土元素

本文制备了氨基羧酸纤维滤纸片作为柱填充物，成功地分离和富集了地化样品中的多种稀土元素。富集后的稀土元素采用电感耦合等离子体原子发射光谱法测定，回收率为90％～109％。本文还对基体干扰及其消除进行了研究。     

氧极谱催化波法测定二苯胺

本文报道一种极谱测定二苯胺的新方法,它是基于二苯胺引起的氧极谱催化波.这个氧极谱催化波是由于二苯胺催化了电生超氧离子O_2~(-)的歧化反应产生的.本方法简单方便,有良好选择性.应用本方法测定了化工原料二苯胺的含量,结果令人满意.     

羧酸直接酰胺化的一个新方法

N, N-二甲基取代酰胺可以方便地由脂肪族或芳香羧酸与四(二甲氨基)硅烷在无水溶剂中反应制得。     

Nonequilibrium solid phase formation studied by lattice dynamics calculation and ion beam mixing in an immiscible Co-Ag system

For the equilibrium immiscible Co-Ag system, a proven realistic ab initio derived n-body potential is applied to study the nonequilibrium solid phase formation at three chemical stoichiometries of Co/Ag = 1:3, 1:1, and 3:1. To predict the structural stability, the elastic constants and the phonon spectra are calculated at the chosen stoichiometries with a total of eight hypothetical crystalline structures. The calculated results suggest that four compounds, that is, D0(3) CoAg3, B1 CoAg, B2 CoAg, and D0(3) Co3Ag, are unstable, as they all feature negative elastic constants as well as imaginary phonons, and that another four compounds of both fcc-type L1(2) and hcp-type D0(19) structures at chemical stoichiometries of Co/Ag = 1:3 and 3:1, respectively, may elastically be favored and therefore obtainable under some specific conditions. It is also found that all the calculated elastic constants and phonon spectra are coincident within the framework of the elastic theory. Moreover, the calculated elastic constants are in good agreement with those acquired directly from ab initio calculations, lending support to the validity of the ab initio derived n-body Co-Ag potential as well as its resultant elastic constants and the phonon spectra. Interestingly, some of the predicted nonequilibrium solid phases, that is, two hcp-type compounds at chemical stoichiometries of Co/Ag = 1:3 and 3:1, respectively, are indeed obtained in ion beam mixing experiments and their lattice constants determined by diffraction analysis are in good agreement with those from calculations.     

碱改性γ－Al_2O_3催化剂表面碱强度分布与COS水解活性的研究

用非水滴定法和Ｈａｍｍｅｔｔ系列指示剂测定了ＣＯＳ水解碱改性γ－Ａｌ_２Ｏ_３催化剂的表面碱强度分布．发现表面碱强度分布不均匀与表面能量分布不均匀相呼应．采用零点酸碱强度（Ｈ_（０，ｍａｘ））及碱中心区域分析法，Ｂｒｏｎｓｔｅｄ催化定律，进一步证实ＣＯＳ水解反应具有明显碱催化特征，较高活性催化剂的Ｈ_（０，ｍａｘ）一般为１０左右，对ＣＯＳ水解反应起主要作用的碱性中心的碱强度（Ｈ_０）为４．８≤Ｈ_０≤９．８．对碱金属氧化物改性后的γ－Ａｌ_２Ｏ_３催化剂，Ｂｒｏｎｓｔｅｄ规律在每个碱强度分区域内是适用的．