旋转开采工艺在大倾角综采工作面的应用

为最大限度的回收煤炭资源,需要在正常布置工作面开采完成后,采用适当的开采工艺对遗留的三角煤进行回收。本文以孔庄煤矿8331工作面开采工艺为例,介绍了大倾角条件下,综采工作面调面开采工艺,为水采采区遗留三角煤的回收或复杂地质条件下采用综采提供了经验。     

Chemical Identification of Specialized Metabolites from Sulla (Hedysarum coronarium L.) Collected in Southern Italy

Sulla (Hedysarum coronarium L.) is a biennal forage legume originated from the Mediterranean basin and used for animal feeding due to its high forage quality and palatability. Several species of Hedysarum have been considered for their nutritional, pharmaceutical, and biological properties, and different applications have been reported, both for human consumption and animal nutrition. Although a systematic investigation of the chemical constituents of Hedysarum spp. has been performed in order to provide chemotaxonomic evidences for the genus and to support the pharmacological application of several species within the genus, few data are available on the chemical constituents of H. coronarium, and only the content of condensed tannins and flavonoids in leaves has been previously reported. In the present paper, results from a detailed chemical analysis of the extracts from the leaves and flowers of H. coronarium grown wild in southern Italy are presented. Identification of the main specialized metabolites within the chemical classes of flavonoids, proanthocyanidins and saponins, is described, including considerations on their content in the two plant organs. Information acquired from this study expands the knowledge on H. coronarium as a source of valuable phytochemicals for different applications in human and animal health and nutrition.     

重大突发事件对国际外汇市场影响分析:基于英国脱欧公投事件

从外汇市场收益率、收益率波动及联动性三个维度全面考察了英国脱欧公投事件对部分世界主要汇率冲击影响全过程。首先,利用时间序列异常点诊断算法研究了公投期间汇率异常波动全过程,发现所有汇率影响显著,但人民币反应具有时滞特征,说明其国际化水平有待进一步提高。进一步,构建了刻画收益率波动的三阶段变结构GARCH模型,结果发现汇率市场异常波动和重大突发事件发生具有显著同步性特征,同时人民币汇率在公投期间波动最小。接着,通过非线性门限协整检验发现汇市之间关联性和共移性较高,公投事件对汇市联动性造成结构性改变,但市场之间依旧保持紧密均衡关系。最后,通过稳健性检验说明了模型选择及结果的合理性。     

Self-consistent optimization of molecular geometries by semi-empirical force field method : Part I. Computational scheme

A force field method based on the semi-empirical force approach is used to predict the completely optimized geometries of both the stationary and the saddle points on the molecular energy hyper-surface. The computational aspects are discussed and the organization of computer programs is briefly described. The convergence properties are examined based on the results obtained from MINDO theory.     

Theoretical studies of molecular complexes: a probe into basis set and correlation effects

We investigate the effect of basis set size, correlation effects and interplanar separation on the theoretical electronic structure of stacking complexes of para- and meta-hydroxyaruline with formamidinium cation, constructed as analogs for the complexes of 5- and 6-hydroxytryptamine with imidazolium cation.     

甘薯叶片衰老的生理变化

用处于不同衰老时期的甘薯叶片为材料，研究了与衰老有关的多项生理指标的变化，比较了品种间抗衰老能力的强弱。结果指出，用能量（ＡＴＰ）耗损的观点结合其与气孔开闭运动的关系的研究，是深入认识和理解叶片衰老机制的有益途径。     

也释“去”

本文从“去”的甲骨文初形出发,辅以“出”、“各”等甲骨文字形体为旁证,释“去”为从大从凵的会意字,其上方部件“大”是正面人形,下方部件“凵”是坑坎或房坑,所表示的内容是人离开穴居之所或坑坎,本义为“离开”。     

Hamilton decompositions of complete multipartite graphs with any 2-factor leave

For m ≥ 1 and p ≥ 2, given a set of integers s₁,…,s_q with for and , necessary and sufficient conditions are found for the existence of a hamilton decomposition of the complete p-partite graph , where U is a 2-factor of consisting of q cycles, the jth cycle having length s_j. This result is then used to completely solve the problem when p = 3, removing the condition that . © 2003 Wiley Periodicals, Inc. J Graph Theory 44: 208–214, 2003     

The fluorescence of all-trans diphenyl polyenes

The temperature dependence of the fluorescence and fluorescence excitation spectra of all-trans diphenyl hexathene (DPH) and octatetraene (DPO) in six solvents confirms the S₁(¹A_g*) and S₂(¹B_u*) state assignment, and determines their energy difference ΔE. The S₁ fluorescence rate parameter k_F depends on ΔE, the solvent refractive index n, the S₂ (n = 1) fluorescence rate parameter k_F20 (2.23 × 10⁸ s^?1 for DPH, 2.33 × 10⁸ s^?1 for DPO), and the S₂-S₁ coupling matrix element V (745 cm^?1 for DPH, 500 cm^?1 for DPO). The S₁ fluorescence is induced by ¹B_u*-¹A_g* potential interaction (PI), via a b_u vibrational mode (≈ 900 cm^?1), and not by vibronic coupling. The main S₁ radiationless transition, rate parameter k_R, is thermally-activated internal rotation through an angle θ about the central ethylenic bond(s). The PI distorts the S₁ (θ) potential surface and thus influences k_R.