乙炔和甲基二氯硅烷的硅氢加成反应研究——Ⅰ. 金属铂胶体的制备及其催化性能

通过直接水解的方法合成了聚甲基乙烯基硅氧烷,首次以此作为保护剂,加热二甲苯溶剂下的氯铂酸,得到了稳定的金属铂胶体。通过观察形成时及进行硅氢加成反应４ｈ后的胶体粒子的ＴＥＭ,考察了它和原位氧化还原法得到的铂胶体的稳定性,并对比考察了他们的硅氢加成反应活性和     

超环面聚焦镜压弯装置的优化设计

介绍了同步辐射光束线中,超环面聚焦镜四点压弯装置的机械压弯原理,建立了四点压弯装置的数学模型.针对压弯柱面镜子午方向微小（最大挠度为10－2mm级）弯曲变形,给出理论圆弧线与实际压弯挠曲线之间误差非线性函数,采用CAE技术对误差函数的求解,优化了压弯点力学参量l,使误差函数取值最小.最后通过北京中能辐射光束线中超环面聚焦镜的工程实践,验证了优化设计的正确性.     

Efficient Deep Blue Platinum Acetylide Phosphors with Acyclic Diaminocarbene Ligands

Here we report five blue-phosphorescent platinum bis-phenylacetylide complexes with an investigation of their photophysical and electrochemical attributes. Three of the complexes ( 1 – 3 ) are of the general formula cis-Pt(CNR)₂(C≡CPh)₂, in which CNR is a variably substituted isocyanide and C≡CPh is phenylacetylide. These isocyanide complexes serve as precursors for complexes of the general formula cis-Pt(CNR)(ADC)(C≡CPh)₂ ( 4 and 5 ), in which ADC is an acyclic diaminocarbene installed by amine nucleophilic addition to one of the isocyanides. All of the complexes exhibit deep blue phosphorescence with λ_max ∼430 nm in poly(methyl methacrylate) (PMMA) thin films. Whereas isocyanide complexes 1 – 3 exhibit modest photoluminescence quantum yields (Φ_PL), incorporation of one acyclic diaminocarbene ligand results in a three-fold to 16-fold increase in Φ_PL while still maintaining an identical deep blue color profile.     

POLYNOMIAL REPRESENTATIONS OF THE h AFFINE NAPPI-WITTEN LIE ALGEBRA H4

In this paper,the representation theory for the affine Lie algebra H4 associated to the Nappi-Witten Lie algebra H4 is studied.Polynomial representations of the affine Nappi-Witten Lie algebra H4 are given.     

1.55-μm coherent lidar based on SPA sinusoidal frequency demodulation techniques

A 1.55-μm all-solid frequency-modulated continuous-wave (FMCW) coherent lidar based on the sinusoidal frequency demodulation technique for range and velocity measurement is presented. Both the nonlinearity of linear modulation waveform and the difficulty in measuring the frequency of sinusoidal modulation sys- tem are circumvented by utilizing segmental-processing-average (SPA) techniques. The results demonstrate that the resolutions of range and velocity measurement are better than 2 mm and 0.1 mm/s, respectively. The system has numerous practical and potential applications in space missions.     

Acceleration of Petasis reactions of salicylaldehyde derivatives with molecular sieves

Mild reaction conditions for Petasis reactions of substituted salicylaldehydes with various amines and arylboronic acids in the presence of molecular sieves were developed. Molecular sieves (MS) significantly accelerated the reaction rates and drove the reactions to high conversions. The conditions were applied to the synthesis of the core structure of BIIB042, a γ-secretase modulator, without stereochemical erosion of a stereogenic center in the salicylaldehyde intermediate.     

Rapid access to multi-substituted pyrimido[4,5-b][1,4]diazepine-2,4,6-trione and pyrimido[4,5-b][1,4]diazepine-2,4-dione as novel and versatile scaffolds for drug discovery

A novel pyrimido[4,5-b][1,4]diazepine-2,4,6-trione was synthesized with an efficient strategy. Especially, the key intermediate 2,4-dimethoxypyrimido[4,5-b][1,4]diazepin-6-one was promoted by one pot tandem reduction-cyclization with Na₂S₂O₄. Subsequently, reduction of lactams 6 with LiAlH₄ afforded a more flexible scaffold of pyrimidodiazepines. The synthetic strategy was versatile since it facilitated the sequential functionalization on the pyrimidodiazepine at three positions. Thus a convenient and effective method for the rapid preparing of multi-substituted pyrimido[4,5-b][1,4]diazepines was developed.     

Quantitative determination of lisinopril in human plasma by high performance liquid chromatography-tandem mass spectrometry and its application in a pharmacokinetic study

A rapid, selective and sensitive high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed to determine lisinopril in human plasma. Sample pretreatment involved a one-step protein precipitation with methanol of 0.1 mL plasma. Analysis was performed on an Inertsil ODS-3 column (2.1 × 50 mm i.d., 3 μm) with mobile phase consisting of methanol-water (containing 0.2% formic acid; 55:45, v/v). The detection was performed on a triple quadrupole tandem mass spectrometer in multiple reaction monitoring mode via an electrospray ionization source. Each plasma sample was chromatographed within 2.5 min. The linear calibration curves for lisinopril were obtained in the concentration range of 1.03-206 ng/mL (r(2) ≥ 0.99) with a lower limit of quantification of 1.03 ng/mL. The intra- and inter-day precisions (relative standard deviation) were not higher than 11%, and accuracy (relative error) was within ±6.8%, determined from quality control samples for lisinopril, which corresponded to the guidance of the Food and Drug Administration. The method described herein was fully validated and successfully applied to the pharmacokinetic study of lisinopril tablets in healthy male volunteers after oral administration.     

Novel synthesis of 8-deaza-5,6,7,8-tetrahydroaminopterin analogues via an aziridine intermediate

An efficient method for the construction of the tetrahydrofolate skeleton is described. Starting from pterin analogues and aromatic amines, 8-deaza-5,6,7,8-tetrahydroaminopterin derivatives and the heterocyclic benzoyl isosteres were synthesized via a novel aziridine intermediate. Following this method, the byproducts of carbon-nitrogen bond hydrogenolysis in traditional synthetic strategy can be completely avoided.     

基于正弦波磁光调制的方位失调角精确测量方法

针对传统基于正弦波磁光调制的方位失调角测量系统存在测量精度不高的问题,提出了一种新的系统方位失调角测量模型以提高系统测量精度。通过分析传统的基于正弦波磁光调制的方位失调角测量原理发现,由于采用省略高阶项的贝塞尔函数展开式表示磁光调制后的信号,引入了信号截断误差和方法误差,影响了系统测量精度。在分析基础上推导建立了一种基于纯三角函数表示的无理论误差的方位失调角测量新模型并进行了仿真。仿真结果表明,利用推导建立的失调角测量新模型,系统测量精度明显高于传统方法,这对重新理解基于正弦波磁光调制的方位失调角测量系统原理、提高系统测量精度具有一定的参考意义。