Rapid Dynamic Determination of Cetirizine Dihydrochloride in Urine Using Surface Enhanced Raman Scattering with Silver Colloids

A novel method for the dynamic determination of cetirizine dihydrochloride in urine using surface enhanced Raman scattering (SERS) has been developed. Comparison of SERS activities between gold and silver colloid was made based on the analysis of the transmission electron micrographs and the SERS spectra, revealing that silver colloid is much more efficient on the signal enhancement performance. The primary sites of the adsorption on the nanoparticle surface were represented by the feature peaks of piperazine at ca. 1050?cm^?1 and phenyl rings at ca. 1630?cm^?1, respectively. The best signal response was extracted at pH 7 at the Cl^?:Ag⁺ molar ratio of 2:1. The matrix effect was eliminated by subtracting the spectral contribution of the blank urine from the sample spectra. Sample preparation procedures were minimized. Quantification could be simply accomplished on the predicted versus actual concentration curve, within the Raman shift range from 500 to 2500?cm^?1. Neither modeling nor complicate calculation was required. The method was shown to be specific and applicable for drug urine concentration monitoring in situ.     

Harmonic oscillator tensors. III: Efficient algorithms for evaluating matrix elements of vibrational operators

Succinct expressions for the matrix elements of various vibrational operators have been derived in the basis of the nondegenerate harmonic oscillator. Among these are the matrix elements of and , which are found to be dependent upon two quantities and their derivatives. Furthermore, the derivative property of the commutator is used to obtain an explicit expression for the derivatives of an operator in terms of its nested commutator with the conjugate momentum. It may be applied to any of the above cases to obtain the matrix representatives of expressions such as the mixed products , for example. In addition, a simple expression for 1/q is given and its derivatives may be evaluated by this commutator technique. Also the matrix elements of a Gaussian-type operator has been evaluated. This revised version was published online in July 2006 with corrections to the Cover Date.     

Ultrafast x-ray diffraction using a streak-camera detector in averaging mode

We demonstrate an apparatus for measuring time-dependent x-ray diffraction. X-ray pulses from a synchrotron are diffracted by a pair of Si(111) crystals and detected with an x-ray streak camera that has single-shot resolution of better than 1 ps. The streak camera is driven by a photoconductive switch, which is triggered by 100-fs laser pulses at a repetition rate of 1 kHz. The laser and the streak camera are synchronized with the synchrotron pulses. In the averaging mode, trigger jitter results in 2-ps temporal resolution. We measured the duration of 5-keV pulses from the Advanced Light Source synchrotron to be 70ps.     

Synthesis and Crystal Structure of a Novel Diorganotin（Ⅳ） Complex Containing 3,4-Difluorobenzohydroxamato Ligand

In recent years, there has been considerable interest in organotin(Ⅳ) compounds. One of the important reasons is that many organotin compounds are biologically active1-3. The diorganotin(Ⅳ) complex containing carboxylate ligand have been investigated fo…     

Three New Compounds from Forsythia Suspensa (Thunb.) Vahl

Forsythiasuspensa(ThUnb.)VahlhasbeenusedintradihonalChinesemedicineforanhiallammatoryandamibacterialpmposes.AnUInberofcompoundssuchasforsythiaside,phillygeninrengyoletc.haVebeenidentifiedl-#fromthefactsofmisplat.AsPartofourstudyontheachveprinciplesoftradihonalChinesemedicine,wereinvestigatCdthechemicalconstitllentsofRsuspensa.heartycompoundshavebeenisolatCdfromthisspecies.ThispaperdescribesthestrUcturalelucidahonofthreenewcompoundsfsuspenolicacid(1),forSythensideA(2),andforsythensideB(3)…     

A Novel White Light Emitting Long-lasting Phosphor

A novel white light emitting long-lasting phosphor Cd1-xDyxSiO3 is reported in this letterThe Dy^3 doped CdSiO3 phosphor emits white light. The phosphorescence can be seen with the naked eye in the dark clearly even after the 254nm UV irradiation have been removed for about 30min. In the emission spectrum of 5% Dy^3 doped CdSiO3 phosphor, there are two emission peaks of Dy^3 , 580nm (^4F9/2→^6H13/2) and 486nm (^4F9/2→^6H15/2), as well as a broad band emission located at about 410nm. All the three emissions form a white light with CIE chromaticity coordinates x=0.3874, y=0.3760 and the color temperature is 4000 K under 254 nm excitation. It indicated that this phosphor is a promising new luminescent material for practice application.     

Influences of Hard Donor on Cation Selectivities Closing to Soft Selenium Donor in Tweezer-like Calix[4]arene Receptors

Three novel 25,27-dihydroxy-26,28-bis(3-benzylselenopropoxy)-5,11,17,23-tetra-tert-butylcalix[4]-arene (2),25,27-dihydroxy-26,28-bis[3-(2-hydroxyethylseleno)propoxy]-5,11,17,23-tetra-tert-butyl-calix[4]arene (3) and 25,27-dihydroxy-26,28-bis(3-propylselenoproppxy)-5,11,17,23-tetra-tert-butyl-calix[4]arene (4) were synthesized for the comparison of their ion-selectivity in ion-selective electrodes (ISE). X-ray structure of the CH/π complex of 4.CH2Cl2 was elucidated. ISEs based on 2-4 as neutral ionophores were prepared, and their selectivity coefficients for Ag (logKAg,M^pot) were investigated against some main group metal ions and transition metal ones using the fixed interference method (FIM). These ISEs showed excellent Ag^ selectivity over most of the interfering cations examined. It is evident that the stronger Hg^2 interference may not be produced while hard donors (hydroxy) are close to the soft selenium donors.     

混合三烃基锡有机酸酯化合物构效关系 （Ⅰ）二环己基－甲基－2，4－二溴－β－甲基苯氧乙酸锡酯 及二环己基－甲基－2－甲氧基－4－丙烯基苯氧乙酸锡酯的晶体结构和分子结构

报道２，４－Ｂｒ２Ｃ６Ｈ３ＯＣＨ（ＣＮ３）ＣＯ２Ｓｎ（Ｃ６Ｈ１１）２ＣＵ３（１）和２－ＯＣＨ３－４－ＣＨ３ＣＨ＝ＣＨＣ６Ｈ３ＯＣＨ２ＣＯ２Ｓｎ（Ｃ６Ｈ１１）２ＣＨ３（Ｈ２Ｏ）（Ⅱ）的晶体结构和分子结构。（Ⅰ）单斜晶系，空间群Ｐ２１／ｃ，ａ＝１３．０６７（３），ｂ＝１０．５９４（３），ｃ＝１８．１５７（４），β＝１０６．９９（２）°，Ｚ＝４，Ｄｃ＝１．６７２ｇ／ｃｍ３，Ｖ＝２４０３．７３，μ＝４３．７３１ｃｍ－１，Ｍｒ＝６２２．９９，Ｆ（０００）＝１２３２；（Ⅱ）单斜晶系，空间群Ｐ２１／ｎ，ａ＝１０．４０９（１），ｂ＝　１２．５７０（２），ｃ＝２０．６６４（２），β＝８３．５１（１）°，Ｚ＝４，Ｄｃ＝１．２８１ｇ／ｃｍ３，Ｖ＝２６８６．４Ａ３，μ＝９．７６１ｃｍ－１，Ｍｒ＝５３９．２８，Ｆ（０００）＝１１２０．最后的偏离因子，化合物（Ⅰ）Ｒ＝０．０４６，Ｒω＝０．０４６；化合物（Ⅱ）Ｒ＝０．０４９，Ｒω＝０．０４７。晶体结构解析表明，化合物（Ⅰ）和（Ⅱ）中的锡均被配体的３个碳和２个氧原子配位，配位原子呈畸变三角双锥构型；化合物中的环己基均为椅式构象；化合物（Ⅱ）中，配位水分子和另一分子的羰基氧与芳环上的甲基氧?     

Kinetics and Mechanism of the Reduction of Enneamolybdonickelate(IV) by Arsenite

The kinetics and mechanism of the reduction of enneamolybdonickelate(IV) by arsenite in aqueous acid solution was studied by spectrophotometry. The reaction rate increases with increasing concentrations of H⁺ and with temperature. The associated rate law is: . The rate constants and activation parameters of the rate-determining step were evaluated. A mechanism related to this reaction was proposed.     

正化学源-气相色谱-质谱法测定食用植物油中有机锡化合物残留

建立了正化学源-气相色谱-质谱技术测定食用植物油中有机锡化合物残留的方法。食用油样品经环己烷-乙酸乙酯（1：1，v/v）溶解后，经凝胶渗透色谱（GPC）净化，目标馏分用四乙基硼酸钠进行衍生。采用基质校正曲线外标法定量，在20~2000 μg/L范围内，7种有机锡化合物均呈现良好的线性关系，相关系数大于0.99，定量限为0.3~1.2 μg/kg。对芝麻油样品进行加标回收试验，在0.05、0.10、0.20 mg/kg 3个添加水平下，7种有机锡化合物的平均回收率为66.2%~103.2%，相对标准偏差均小于11.5%。该方法精密度好，灵敏度高，可用于食用植物油中有机锡化合物残留量的测定。