Development and Validation of UV Spectrophotometric Method to Study Stress Degradation Behaviour of Rizatriptan Benzoate

Rizatriptan benzoate is a 5HT 1B/1Dreceptor agonist which is prescribed for the treatment of migraine.In the present study new,simple,specific ultraviolet spectrophotometric method for rizatriptan benzoate was developed and validated.Forced degradation studies were carried out in acidic,alkaline and neutral pH conditions.The absorbance maxima peak was found to be 224 nm and linearity was observed in the concentration range of 0.5~2.5μg·mL-1 with regression coefficient value of 0.998 8.The method was validated and found to be precise.The percent recovery for rizatriptan benzoate was found to be 98.576±0.202.The bulk drug was found to be stable in neutral and acidic pH conditions but got degraded in 1N NaOH solution.     

EDTA-柠檬酸法合成的SrCo0.8Fe0.2O3-δ钙钛矿的结构及制氧性能研究

采用EDTA-柠檬酸联合络合法合成了钙钛矿型金属氧化物SrCo_0.8Fe_0.2O_3-δ(SCF182)粉体。通过XRD和ESEM研究了前驱体溶液不同的pH值对合成的SCF182粉体的晶体结构和微观形貌的影响。并采用固定床实验研究前驱体溶液pH值对SCF182的氧吸附/脱附性能的影响。结果表明,pH值对SCF182晶胞结构和参数影响不大,但影响SCF182的晶粒粒径和微观形貌,当pH值为8的弱碱性条件下时,能够合成蓬松多孔网状纳米结构的钙钛矿粉体。固定床实验显示,前驱体溶液的pH值影响合成的粉体SCF182的氧吸附速率;且SCF182的氧脱附性能随pH值的增大先升高后降低,pH值为8时氧脱附量达到峰值为42.2 mg/g。     

不同钼锆质量比MoO3-ZrO2复合氧化物的结构及催化活性研究

采用溶胶凝胶法制备介孔MoO₃-ZrO₂复合氧化物,考察MoO₃/ZrO₂的质量比对其晶相结构、比表面积、孔径以及形貌特征的影响。利用XRD、N₂吸附-脱附、SEM及FT-IR表征对所制得的复合氧化物进行分析。以FCC汽油馏分为原料,对MoO₃-ZrO₂经预硫化后制得的催化剂进行加氢脱硫评价。结果表明,含有MoO₃的ZrO₂与不含MoO₃的ZrO₂相比单斜相减少,主要以稳定的四方相存在。适当的提高MoO₃/ZrO₂的质量比有利于MoO₃-ZrO₂复合氧化物的比表面积和平均孔径的增大,但过大的质量比并不利于介孔的生长,并且有新的化合键和少量Zr(MoO₄)₂相产生。当MoO₃/ZrO₂的质量比为30%时,ZrO₂表面出现蠕虫状结构,此时脱硫率最高。由此,适当提高MoO₃/ZrO₂质量比可使催化剂的脱硫率升高。     

6-羟基石松碱与乙酰胆碱酯酶的相互作用

目前治疗阿尔茨海默症(Alzheimer’s disease,AD)的主要药物为乙酰胆碱酯酶抑制剂(AChEI).为探讨石松碱类化合物对AChE的抑制作用,以6-羟基石松碱(6-hydroxylycopodine,HLD)为对象,应用核磁共振、分子对接、酶活性测定、分子动力学模拟及自由能分析,研究了HLD与AChE的相互作用.研究发现6-羟基石松碱对乙酰胆碱酯酶具有混合型抑制作用,其结合作用主要来自氢键和范德华作用.     

Recent results from NA48/2

Recent results on radiative K^± decays from the NA48/2 experiment are reported. From the full NA48/2 data set, about a million K^±→π^±π^γ decays were reconstructed. Based on this sample, the first measurement of the interference between direct photon emission and inner bremsstrahlung in K^±→π^±π^γ decays was performed. Stringent limits on CP violation in this decay were also set. In addition, a precise measurement of the branching fraction of K^±→π^±γγ is presented. This measurement was based on a data sample of more than 1000 event candidates. Also the related decay K^±→π^±e^＋e^-γ has first been observed. Results of the measurement of the decay rate and the decay parameter 5 are summarized.     

Photoproduction of ω-Mesons at ELSA and the role of azimuthal asymmetries

Measurements of ω photoproduction of the Crystal-Barrel/TAPS experiment at the ELSA accelerator of Bonn University are presented which used linearly polarized tagged photon beam from threshold to Eγ = 1700MeV. The azimuthal asymmetries ∑and ∑πindicate s-channel resonance contributions on top of the established t-channel exchange processes. These findings are further enhanced by a very first measurement of the G-asymmetry which, in addition to the polarized photon beam, also requires a longitudinally polarized proton target. An intuitive interpretation of the specific sensitivity of the azimuthal asymmetries to the reaction mechanisms involved is given.     

表面官能化碳纳米管13C NMR参数的理论研究

碳纳米管表面化学修饰是当前研究的一大热点,修饰后由于极性基团的存在,碳纳米管在极性溶液环境中的分散度得到明显改善,这在很大程度上扩展了纳米管研究的应用范围. 本文采用C₈₀ H₂₀模型来表示（10,0）碳纳米管,基于此模型计算了一系列氮烯、卡宾和氟化的单壁纳米管的结构、偶极矩,以及核磁共振参数. 研究表明高精度的密度泛函理论（DFT）计算能够用来预测纳米管的¹³C化学位移,理论研究的结果揭示了氮烯、卡宾以及1,2和1,4氟化的单壁纳米管的若干¹³C信号特征化学位移值,为实验NMR谱图的归属提供了一定的依据,并且可通过与实验相结合来监测表面官能化碳纳米管加成反应是否发生以及确认其加成方式.     

2-取代-4(3H)-喹唑啉酮在BrФnsted酸性功能化离子液体中的微波合成

以N-甲基咪唑、吡啶为起始原料,合成了二种新型BrФnsted酸性功能化离子液体:1-(4-磺酸基)苄基-3-甲基咪唑硫酸氢根盐(3a),N-(4-磺酸基)苄基吡啶硫酸氢根盐(3b),以其作为反应介质与催化剂,研究了2-取代-4(3H)-喹唑啉酮的三组分、一锅法微波合成.结果表明,当n(2-氨基苯甲酸):n(酰氯):n(乙酸铵):n(3a或3b)=1:1.2:1.5:0.1时,反应6min即可完成,产率81%～95%.离子液体经减压蒸馏、真空干燥可重复使用3次,催化活性基本保持不变.     

弱束缚核17F弹性散射角分散

在兰州放射性束流线(RIBLL)上完成了¹⁷O/¹⁷F+²⁰⁸Pb的弹性散射微分截面角分布测量. 分析了¹⁷O/¹⁷F弹性散射产物的角分散, 即微分截面的对数ln(dσdθ)随散射角平方θ²的依赖关系. 结果表明, 在所测量的角度范围内(6°—20°), ¹⁷O的这一依赖关系可以用一条直线很好地拟合, 而¹⁷F的这一依赖关系需要两条不同斜率的直线才能拟合. ¹⁷F数据拟合中的这种斜率改变可能 起因于¹⁷F的奇异结构. 对其他实验组数据的分析支持以上的结论, 即在一定的角度范围内, 弱束缚核与稳定核相比, 弹性散射产物的微分截面与散射角平方的依赖关系有明显的差异, 这可以作为深入研究"晕/皮核"的一个新探针.     

A ROBUST TRUST REGION ALGORITHM FOR SOLVING GENERAL NONLINEAR PROGRAMMING

1. Introductioncrust region methods are iterative. As a strategy of globalization, the trust region approach was introduced into solving unconstrained optimization and proved to be efficient androbust. An excellent survey was given by Mor6(1983). The associated research with trustregion methods for unconstrained optimization can be found in Fletcher(1980), Powell(1975),Sorensen(1981), Shultz, Schnabel and Byrd(1985), Yuan(1985). The solution of the trust region subproblem is still an activ…