High-spin states and signature inversion in odd-odd182Au

High-spin states in¹⁸²Au have been produced and studied via the¹⁵²Sm(³⁵Cl,5nγ)¹⁸²Au reaction. The level scheme consisting of the πh _9/2⊗νi _13/2 and πi _13/2⊗νi _13/2 bands has been established for the first time. The low spin signature inversion in both bands has been found. The observed signature inversion phenomena can be interpreted qualitatively using the pairing and deformation self-consistent cranked Wood-Saxon calculations.     

4,9‐Dihydro‐s‐indaceno[1,2‐b:5,6‐b′]dithiophene‐4,9‐dione functionalized copolymers for organic photovoltaic devices

The synthesis of conjugated polymers 1 – 5 functionalized with 4,9‐dihydro‐s‐indaceno[1,2‐b:5,6‐b′]dithiophene‐4,9‐dione in the backbone is reported and their use in the construction of organic solar cells is demonstrated. Increasing the molar ratio of 2,7‐dibromo‐3,8‐dihexyl‐4,9‐dihydro‐s‐indaceno[1,2‐b:5,6‐b′]dithiophene‐4,9‐dione, relative to 4,4′‐dihexyl‐5,5′‐dibromo‐2,2′‐bithiophene, in the copolymer synthesis significantly lowers the solubility of these polymers. The incorporation of highly conjugated 3,8‐dihexyl‐4,9‐dihydro‐s‐indaceno[1,2‐b:5,6‐b′]dithiophene‐4,9‐dione unit into the polymer backbone has been confirmed by UV–vis absorption. The observation of decreasing quantum yield for the emission in the order of 1 , 2 , 3 is consistent with copolymers with different comonomer content. The power conversion efficiencies of solar cells using blends of these polymers with PCBM ([6,6]‐phenyl C₆₁‐butyric acid methyl ester) were determined to be 0.11% for polymer 1 , 0.33% for 2 , and 0.26% for 3 , respectively. Under identical white light illumination, the power conversion efficiency of the device based on polymer 2 /PCBM as the active layer was three times higher compared to that of device based on polymer 1 /PCBM. Owing to the limited solubility and poor film‐forming ability of polymer 3 , the power conversion efficiency of solar cell based on 3 /PCBM blend is lower than that of 2 /PCBM blend, but is still larger than that of 1 /PCBM blend. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2680–2688, 2008     

测量线路中的漏电来源及防护措施

本文以单臂电桥为例，分析测量线路中的漏电来源以及采取适当措施的方法。     

二苯二硫和二苄二硫润滑性能的量子化学研究

用Gaussian03W程序在B3LYP/631G和HF/631G水平上对二苯二硫(DPDS)和二苄二硫(DBDS)的分子几何构型、电子结构、分子轨道指数及与铁原子簇的相互作用等进行了理论计算.用前线分子轨道理论分析了反应的活性原子和活性键,讨论了DPDS和DBDS与铁原子的作用方式,用前线电子密度,超离域性指数,原子净电荷及化合物与铁原子簇的化学吸附作用能等参数作为判据分析了DPDS和DBDS与铁原子间键合的强弱,反应性的大小.计算结果表明DPDS和DBDS与铁接触时,趋向于S-S键与C-S键断裂,在较为缓和的摩擦条件下,DPDS的抗磨作用优于DBDS,在较为苛刻的摩擦条件下,DBDS的极压作用优于DPDS,与摩擦学试验结果一致.     

Observation of signature inversion in the πh9/2(×)νi13/2 oblate band

High-spin states in 190Tl have been studied via the 160Gd(35Cl, 5nγ) reaction. The level scheme, consisting of the πh9/2(×)νi13/2 oblate band and a cascade with character of single particle excitations, has been established. Spin values have been firmly assigned to the oblate band in 190Tl, resulting in low-spin signature inversion in the πh9/2(×)νi13/2 oblate band for the first time. Based on the similarity of the level structure in doubly odd Tl nuclei, spin values for the oblate bands in 192―200Tl should be re-assigned, and a consistent low-spin signature inversion has occurred in these oblate deformed nuclei. The low-spin signature inversion phenomena can be interpreted qualitatively by using the 2-quasiparticle plus rotor model including p-n residual interactions.     

缺中子核197Bi的能级结构研究

用100MeV¹⁶O束流轰击厚的天然Re靶和¹⁸⁷Re同位素靶,布居了¹⁹⁷Bi的高自旋激发态.用y-y-t符合测量,发现并修正了已有的¹⁹⁷Bi能级纲图中的错误,确定了¹⁹⁷Bi的三个新的高自旋同质异能态,识别出了11条新γ跃迁.并从奇A Bi核能级结构的系统性,对本工作确定的半寿命t_1/2=19.3±4.9ns的同质异能态的组态和衰变性质进行了探讨.本工作还测量了γ跃迁的角分布,建议了¹⁹⁷Bi的新的能级纲图.     

柔性作业车间调度与视情维修的联合决策

针对设备状态可直接或间接检测获得的生产系统,提出柔性作业车间调度和视情维修的联合策略,决策变量分别为调度序列与视情维修序列,并建立两者的联合决策模型。进而根据联合策略,推导了相应的概率密度函数。通过数值分析,对比联合决策与独立决策的优化结果,表明了所建模型的有效性,并进行设备劣化参数的敏感度分析,验证了模型的正确性。     

Electrochemical synthesis of metal and semimetal nanotube-nanowire heterojunctions and their electronic transport properties

Metal and semimetal nanotube-nanowire heterojunction arrays have been achieved by sequential electrochemical-deposition inside the nanochannels of anodic aluminium oxide template with a layer of Au thin enough to leave the pores open.     

A novel long path length absorbance spectroscopy for the determination of ultra trace organophosphorus pesticides in vegetables and fruits

A simple, rapid, sensitive and reproducible spectrophotometry for determination of ultra trace organophosphorus pesticides (OPs) with liquid core waveguide light intensity technique is presented. OPs were degraded into phosphate with UV light, potassium peroxydisulphate as oxidant and nanosized titanium dioxide as catalyst. Under the optimum selected conditions, linear light intensity response was obtained in the range of 2.0 x 10(-11) to 8.0 x 10(-10)g mL(-1) phosphate, and the limit of detection (LOD) 6.7 x 10(-12)g mL(-1) was achieved. Both the low limit of linear range and the LOD of the proposed method were lower over 1000-fold than that of classical spectrophotometry. The proposed method was applied to the determination of ultra trace OPs in vegetables and fruits samples.     

Characterization of microemulsion liquid chromatography systems by solvation parameter model and comparison with other physicochemical and biological processes

The solvation parameter model has been applied to characterize four microemulsion liquid chromatography (MELC) systems and two micellar liquid chromatography (MLC) systems, and utilized to compare the above systems with other physicochemical and biological processes in this study. The microemulsion mobile phases were composed of sodium dodecyl sulfate (SDS), polyoxyethylene (23) lauryl ether (Brij 35), butanol, heptane and phosphate buffer (pH 7.0) at the designated ratios. The results showed the main difference between the concerned MELC and MLC systems was the decrease of hydrogen-bond basicity of stationary phase with the addition of heptane in microemulsion. Principal component analysis with normalized coefficients can provide consistent results involving the similarities among various systems with that obtained by distance parameter d. Except for some proven similarities of chromatographic systems to octanol-water partition coefficients (logP) and human skin permeation (logK(p)), a microemulsion HPLC system, the mobile phase being 3.3% SDS-6.6% butanol-1.6% heptane-88.5% buffer, was found very similar to drug penetration across blood-brain barrier and its predictive capability for this biological process was originally evaluated in this study.