差示扫描量热法(DSC)定量测试阿德福韦酯晶型的研究

红外光谱（FTIR）和x-射线衍射（XRD）测试表明阿德福韦酯药物具有A、E2种晶型．利用差示扫描量热法（DSC）对阿德福韦酯药物的不同晶型进行了定量测试方法的研究,该方法的依据是药物的不同晶型具有不同的熔点和熔融热焓,根据熔融热焓的量可以定量测试药物中某种晶型的含量,为指导生产工艺研究和产品品质的判断提供快速准确及有效的测试方法。     

在线气体分析的电晕放电大气压电离质谱

研制了适合在线气体分析的电晕放电大气压电离源(corona discharge atmospheric pressure ionization source)及其与商品质谱仪(LTQ-MS)的接口,对其试剂离子的产生机理进行了研究,以H2O. (H2O)为试剂离子,对乙醇气体进行检测,并分析了该离子的产生机制。实验结果表明:在潮湿氮气中电晕放电产生的主要试剂离子是m/z36、37和55;而在含丙酮的潮湿氮气中则产生m/z59和76等离子。利用静态顶空-电晕放电大气压电离质谱对不同浓度的乙醇水溶液进行分析,结果表明:以m/z64为检测对象,乙醇气体浓度的最低检出限可达2.4×10-7g/L;而以m/z47为检测对象,检出限为5.9×10-6g/L。同时还利用动态顶空-电晕放电大气压电离质谱对栀子花香气成分进行了检测,为生物挥发性物质的在线检测提供了一种新方法。     

不同晶形纳米碳酸钙的制备及其表面改性研究进展

本文综述了不同晶形纳米碳酸钙的制备方法、纳米碳酸钙表面改性技术的研究现状以及表面改性方法,分析了目前纳米碳酸钙制备及表面改性技术存在的问题,并对其发展前景作了展望.     

On Form Invariance, Lie Symmetry and Three Kinds of Conserved Quantities of Generalized Lagrange's Equations

In this paper, the form invariance and the Lie symmetry of Lagrange's equations for nonconservative system in generalized classical mechanics under the infinitesimal transformations of group are studied, and the Noether's conserved quantity, the new form conserved quantity, and the Hojman's conserved quantity of system are derived from them. Finally, an example is given to illustrate the application of the result.     

Surface Modification Strategy for Enhanced NO2 Capture in Metal–Organic Frameworks

The interaction strength of nitrogen dioxide (NO₂) with a set of 43 functionalized benzene molecules was investigated by performing density functional theory (DFT) calculations. The functional groups under study were strategically selected as potential modifications of the organic linker of existing metal–organic frameworks (MOFs) in order to enhance their uptake of NO₂ molecules. Among the functional groups considered, the highest interaction energy with NO₂ (5.4 kcal/mol) was found for phenyl hydrogen sulfate (-OSO₃H) at the RI-DSD-BLYP/def2-TZVPP level of theory—an interaction almost three times larger than the corresponding binding energy for non-functionalized benzene (2.0 kcal/mol). The groups with the strongest NO₂ interactions (-OSO₃H, -PO₃H₂, -OPO₃H₂) were selected for functionalizing the linker of IRMOF-8 and investigating the trend in their NO₂ uptake capacities with grand canonical Monte Carlo (GCMC) simulations at ambient temperature for a wide pressure range. The predicted isotherms show a profound enhancement of the NO₂ uptake with the introduction of the strongly-binding functional groups in the framework, rendering them promising modification candidates for improving the NO₂ uptake performance not only in MOFs but also in various other porous materials.     

Synthesis and Crystal Structure of a Novel 1D Coordination Polymer: [Pr(BYBA)3(H2O)2]·[Pr(BYBA)3(H2O)]

The novel coordination polymer [Pr(BYBA)3(H2O)2]·[Pr(BYBA)3(H2O)] (BYBAH = 2-benzoylbenzoic acid) was yielded by hydrothermal synthesis, determined by single-crystal X-ray diffraction, and characterized by FT-IR and UV-Vis spectra. The crystal crystallizes in the triclinic system, space group P with a = 9.112(3), b = 14.644(5), c = 27.076(11) (A), α = 84.223(3), β = 87.816(4), γ = 88.902(4)o, V = 3592(2) (A)3, C84H60O21Pr2, Mr = 1687.14, Z = 2, F(000) = 1700, Dc = 1.560 g/cm3, μ = 1.419 mm-1, the final R = 0.0485 and wR = 0.1258 for 13035 observed reflections with I＞2((I). The compound contains two different building units, [Pr2(BYBA)6(H2O)4] and [Pr2(BYBA)6(H2O)2]. It is noticeable that [Pr2(BYBA)6(H2O)4] is an isolated binuclear building block, in which the Pr3 ion centers are both located in an eight-coordinated environment. However, in [Pr2(BYBA)6(H2O)2] the Pr3 ion centers are located in a nine-coordinated environment and connected by BYBA ligands to form 1D chains.     

Syntheses and Crystal Structures of Two Coordination Polymers with Aromatic Dioxide as Bridge Ligands

Two coordination polymers, namely, two-dimensional complex 1 {[Cu(μ- L)1.5(ClO4)2(H2O)].(H2O)0.5}n (L = pyrazine-1,4-dioxide) and one-dimensional complex 2 [Co(μ-L)Br2(H2O)2]n, have been synthesized with pyrazine-1,4-dioxide as bridging ligands, and their crystal structures were determined by X-ray crystallography. Crystal data for complex 1: monoclinic system, space group C2/c, with a = 23.310(3), b = 12.2338(17), c = 10.6075(15) , β = 110.487(2)°, V = 2833.6(7) 3, Z = 8, C6H9Cl2CuN3O12.5, Mr = 457.60, Dc = 2.145 g/cm3, F(000) = 1832 and μ = 1.998 mm-1; and those for 2: monoclinic system, space group C2/c, with a = 11.012(3), b = 7.483(2), c = 11.451(3) , β = 101.654(4)°, V = 924.2(4) 3, Z = 4, C4H8Br2CoN2O4, Mr = 366.87, Dc = 2.637 g/cm3, F(000) = 700 and μ = 10.487 mm-1. 1 shows a two-dimensional sheet structure on the ac plane through the coordination of μ-L bridging ligands with Cu(II) ions, while 2 displays a zigzag one-dimensional chain along the c axis via the coordination of μ-L bridging ligand with Co(II) ions. Hydrogen bonds in 1 and 2 make the sheets (or chains) connect each other to form a three-dimensional structure.     

Synthesis and Structural Characterization of a New Cadmium(Ⅱ) Complex Bridged by Endo-norbornene-cis-5,6-dicarboxylic Acid

A polynuclear complex [Cd(endc)(H2O)]n·nH2O (endc = endo-norbomene-cis5,6-dicarboxylate anion) has been synthesized by the hydrothermal reaction of cadmium nitrate tetrahydrate with endo-norbomene-cis-5,6-dicarboxylic acid in 1:1 molar ratio,and structurally characterized by single-crystal X-ray diffraction.It crystallizes in monoclinic,space group P21/c with a = 1.16471(7),b = 0.95334(7),c = 0.91109(9) nm,Z = 4,V= 1.01035(14)nm3,Dc.= 2.160 g/cm3,μ= 2.172 mm-1,F(000) = 648,R =0.0302 and wR = 0.0752.According to structural analysis,each Cd(Ⅱ) ion is coordinated to six O atoms from three endc anions and one water molecule,giving a distorted octahedral geometry.Two- dimensional layer arrangement of the title complex is constructed from the bridging nature of endc.It is worth notice that adjacent two-dimensional layers are joined together to form a three-dimensional supramolecular framework via intermolecular hydrogen bonding interactions.     

苯与丙烯在MCM-22型分子筛内吸附行为的Monte Carlo研究

采用巨正则统计系综Monte Carlo模拟方法研究了不同温度、不同吸附方式下纯硅MCM-22型分子筛ITQ-1上苯与丙烯分子的吸附行为. 分子筛内吸附质粒子云分布模拟结果显示, 苯和丙烯主要吸附在超笼和十元环孔道内, 其中丙烯分子几乎充满了孔道内部大部分区域, 在链接超笼之间的十元环窗口也充满了丙烯分子, 而苯分子在超笼内和十元环孔道内的吸附却较为分散、均匀. 丙烯与分子筛之间相互作用能高于苯与分子筛之间的相互作用能, 使苯分子吸附相对丙烯分子更为稳定. 温度变化对分子筛上丙烯吸附远大于对苯吸附的影响, 100 kPa时温度由298 K升高至443 K导致丙烯分子吸附量迅速减少, 而对苯分子却没有显著的影响. ITQ-1分子筛上存在苯和丙烯分子的竞争吸附, 使两者吸附相互作用能最可几分布朝着折中方向移动. 苯与丙烯在分子筛内吸附等温线的模拟结果表明, 在温度较高、压力较低时, 丙烯的吸附量小于苯的吸附量.