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81.
A systematic semiquantitative account of all aspects of the strong and electromagnetic interactions of all the newly discovered hadronic states (theψ’s, theχ’s, etc.) is presented within the framework of the paracharge scheme. Extensions of ideas familiar from the SU3 classification scheme to SU4 are shown to provide an understanding of the new states seen in the decays ofψ (3.1) andψ′ (3.7), including their masses and gross decay characteristics. The decays ofψ (3.1) andψ′ (3.7) themselves are studied in some detail. Since these are of electromagnetic origin in the scheme, their electromagnetic mixing with the resonance at 4.15 GeV (theP-state of the scheme) is important. Once this is taken into account, the resulting picture is in excellent agreement with available data.  相似文献   
82.
Crystal-chemical analysis of the structures of perovskite-like nitrides has been carried out. For cubic phases, the geometrical regions of existence and the most probable compositions have been determined. More than 80 new compounds have been predicted.  相似文献   
83.
This article proposes a new extragradient solution method for strongly pseudomonotone variational inequalities. A detailed analysis of the iterative sequences’ convergence and of the range of applicability of the method is provided. Moreover, an interesting class of strongly pseudomonotone infinite dimensional variational inequality problems is considered.  相似文献   
84.
Anirban Kundu 《Pramana》2000,55(1-2):265-270
In this talk, we point out some of the present and future possible signatures of physics beyond the Standard Model from B-meson decays, taking R-parity conserving and violating supersymmetry as illustrative examples. An expanded version is available on hep-ph archive.  相似文献   
85.
Carbocuprate compounds are generally described as multiple perovskites with CO 3 2 - and Cu-O alternating layers containing Ba and/or Sr; they have gained an unexpected importance in the high temperature superconductivity field, because many compounds with transition temperature above 100 K belong to this class of materials.We have started a systematic study on phase formation and stabilisation in the Ba-Cu-C-O system in the temperature range 20-600°C, by using thermal analysis techniques. Starting from a BaCO3-BaO2-CuO mixture (311 mol), a new phase isomorphic with BaCO3 formed after heat treatment above 390°C in air. TG, DSC, EGA and high temperature XRD were employed to follow the complex interaction of the reactants with the atmosphere and the formation of the new phase.  相似文献   
86.
Pharmacometric characterization studies of liquiritigenin have historically overlooked its chiral nature. To achieve complete characterization, an analytical method enabling the detection and quantification of the individual enantiomers of racemic (±) liquiritigenin is necessary. Resolution of the enantiomers of liquiritigenin was achieved using a simple high‐performance liquid chromatographic method. A Chiralpak® ADRH column was employed to perform baseline separation with UV detection at 210 nm.The standard curves were linear ranging from 0.5 to 100 µg/mL for each enantiomer. Limit of quantification was 0.5 µg/mL. The assay was applied successfully to stereoselective serum disposition of liquiritigenin enantiomers in rats. Liquiritigenin enantiomers were detected in serum as both aglycones and glucuronidated conjugates. Both unconjugated enantiomers had a serum half‐life of ~15 min in rats. The volume of distribution (Vd) for S‐ and R‐liquiritigenin was 1.49 and 2.21 L/kg, respectively. Total clearance (Cltotal) was 5.12 L/h/kg for S‐liquiritigenin and 4.79 L/h/kg for R‐liquiritigenin, and area under the curve (AUC0‐inf) was 3.95 µg h/mL for S‐liquiritigenin and 4.23 µg h/mL for R‐liquiritigenin. The large volume of distribution coupled with the short serum half‐life suggests extensive distribution of liquiritigenin into tissues. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
87.
盐酸吡格列酮的合成新方法研究   总被引:7,自引:0,他引:7  
报道了治疗糖尿病药物盐酸吡格列酮的合成新方法.在六氢吡啶作用下,对羟基苯甲醛和2,4-噻唑烷二酮缩合生成5-[(4-羟苯基)亚甲基]-2,4-噻唑烷二酮,经钯炭催化氢化还原生成5-[(4-羟苯基)甲基]-2,4-噻唑烷二酮,再和氢氧化钾反应生成相应的钾盐,然后与5-乙基-2-羟乙基吡啶和甲基磺酰氯反应得到的磺酸酯作用生成吡格列酮,最后用盐酸酸化得到其盐酸盐.产品结构经1H NMR和IR确证.  相似文献   
88.
High-resolution 17O NMR spectra have been collected for crystalline samples of lanthanum new phase, La3Si8N11O4. In conjunction with previously published 29Si and 15N spectra obtained for this phase, and in the light of the high-quality crystal structure data reported recently, a more detailed interpretation of the NMR spectra is presented than was possible in previous studies. The non-bridging oxygens in the structure are responsible for the single sharp peak seen in the 17O spectrum at 188 ppm; the remaining oxygens, occupying bridging sites shared with nitrogen, show up only weakly on the 17O spectrum as a broad diffuse band centered around zero ppm. The peak at −57.3 ppm on the 29Si spectrum is believed to correspond to an overlap of [SiN4] and [SiON3] environments, with the −68.2 ppm peak corresponding to an [SiO2N2] environment.  相似文献   
89.
双子表面活性剂研究进展和应用   总被引:29,自引:0,他引:29  
双子表面活性剂是一类新型的表面活性剂,它是由联结基团通过化学键将两个或多个单体表面活性剂连接在一起,由此产生优异的表面活性等一系列的性质,从而获得了广泛的应用.本文就它的合成进展及在生物技术、抗病毒、环境保护、新材料制备等方面的应用作一介绍。  相似文献   
90.
将半理想溶液理论和Butler方程相结合建立了预测多元电解质溶液表面张力的新型线性预测方程.新方程可由二元系数据预测多元系的表面张力数据,而不涉及任何多元交互作用参数.利用不同温度下24个混合电解质溶液的表面张力数据对新方程进行了系统检验.结果表明新方程可利用298.15K时二元系的渗透压系数和不同温度下二元系的表面张力数据预测不同温度下高浓度的多元系的表面张力数据,且预测结果与实验数据符合得很好,并且预测结果普遍优于基于Pitzer方程的表面张力模型.  相似文献   
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