电感耦合等离子体发射光谱法测定马口铁中的铅

本文提出了用ＩＣＰ－ＡＥＳ法测定马口铁中的痕量铅。试样用ＮａＯＨ－Ｈ２Ｏ２溶解镀层。测得四种样品的含铅量在０．１４～０．３８μｇ／ｃｍ２范围内。方法的回收率为９６．１％～１０３．２％。方法的精密度（ＲＳＤ）为２．６％～３．８％。本法简便迅速，测量结果的准确度、精密度满足分析要求。     

Structure of 7, 8, 17, 18-Tetrabromo-5,10,15, 20-Tetraphenylporphinatozinc(Ⅱ)

1mrnODUCTIONRecentlywereportedthestructureof7,8,17,18--tetrabromo--5,10,15,20--tetraphenylporphinatozinc(H,TPPBr.)ill.Inordertoobservetheeffectofthefoulelectron--withdrawingbromogroupsonthestructureofametalcomplexofthisPOrphyrin,thetitlecompoundwaspreparedbyanestablishedmethod[Ziandthecrysta:wasobtained,whichissuitableforstructureanalysisbylayeringasolutioninCHCI,withpetroleum(60--90C)--piperidine.2EXPERIMENTALThetitlecomplexwassynthesizedbyreactionofH,TPPBr.andZn(CH,COO):.ZH…     

α1-AR拮抗剂DDPH类似物的比较分子力场分析

利用比较分子力场分析(CoMFA)方法, 建立苯(氧)烷胺类α1-肾上腺素受体拮抗剂DDPH及其类似物的三维定量构效关系模型。交叉验证回归系数q2、非交叉验证回归系数r2和标准偏差SEE分别为0.457, 0.953, 0.208,研究结果显示立体场比静电场对活性的影响更大。所得模型具有一定的预测能力,可用来指导设计新的苯氧烷胺类α1-肾上腺素受体拮抗剂 ,并为以后进一步的工作提供依据。     

c面白宝石衬底表面形貌对气相传输平衡法制备的γ-LiAlO2层质量的影响

采用气相传输平衡(VTE)技术,在(0001)面白宝石衬底表面上成功地制备出单相γ-LiAlO2层.研究了白宝石衬底表面形貌对γ-LiAlO2层质量的影响,发现白宝石衬底的表面粗糙度和退火处理是两个影响γ-LiAlO2层质量的重要因素.要制备高质量的γ-LiAlO2层,适度的表面粗糙度是恰当的.对白宝石衬底进行退火处理,γ-LiAlO2层的择优取向变差.并对其中可能的机理进行了探讨.     

新型功能性显影促进剂的合成

以6-氨基苯并咪唑和苯基巯基三唑为吸附基团,以环状酰肼为显影促进基团,合成了两个新型功能性显影促进剂,其结构经IR,MS和元素分析确证。     

Completeness Relation of the SU(3) Charged and Hypercharged Coherent State

Using the MelJin inversion formulas we derive the weight function for constructing the completeness relation of the boson SU(3) charged and hypercharged coherent state. A suitable contour integration is selected for this derivation.     

High-Frequency ac Conductivity of Hot Electrons in Bulk Semiconductors

On the basis of the balance-eq uation transport theory we have carried out a detailed calculation of the small-signal high-frequency conductivity for n-doped bulk GaAs systems under a de bias. Contributions from impurity and phonon scatterings are taken into account. Attention has been paid to the role of electron bulk plasma modes, which give rise to a significant deviation of the high-frequency conductivity from the Drude formula at low dc bias. It is pointed that when the dc bias increases the plasma effect is suppressed by the rise of the electron temperature while the role of the electron temperature oscillation enhances, leading to an appreciable peak in the real part of the conductivity at low frequency.     

The Effects of Methylene Blue on the Optical Properties of Nanometer-sized CdS Organosol

The inverse micelle system of nanometer-sized CdS doped with Methylene Blue(MB) was synthesized and characterized by using absorption and fluorescence spectra. The results show that MB molecules were absorbed onto the surface of CdS nanoparticles and interacted with surfactants when its concentration was lower than 4×10^-6 mol/L. From the comparison of their spectra, MB molecules by adsorption have a strong quenched fluorescence emission of CdS nanoparticles with surface defect states. All responses and main mechanism are ascribed to the charge transfer between the CdS organosol and Methylene Blue molecules.     

A Novel,General Approach for the Synthesis of Benzimidazole-2-yl Phosphonate

The increasing and sustained interest has been paid to organophosphorus chemistry in the past decades owing to the discovery of more and more naturally occurring C-P compounds, which show antibacterial, antiviral, antibiotic, pesticidal, anti-cancer activity. On the other hand, heterocyclic confounds attract the attention of chemists because of their pharmaceutical importance and various applications in organic synthesis. Three building blocks, α,α-dicyano (α-cyano-α-ethoxycarbonyl) (O, O-dialkyl) phosphonyl/S-methyl ketene acetals and N-cyanoimido-(O, O-dialkyl)phosphonyl/S-methyl thiocarbonates 1,have been developed. To the best of our knowledge, there are no reports on the synthesis of benzimidazole-2-yl phosphonates, which are prepared easily by utilizing above building blocks.     

Study on Determination of multi-insecticides for Public Health with the Same Column by Gas Chromatography

In order to make readily the management of production and quality, we make a thorough study on determination of useful compositions of insecticide for public health producing of Guangxi. It is succeed for applying of analysis of eighteen component in thirty-eight products by gas chromatography(GC)and using one same packed-column.