Ce掺杂CrSi2电子结构和光学性质的第一性原理研究

采用基于密度泛函理论的第一性原理计算方法，对未掺杂及Ce掺杂CrSi2的电子结构和光学性质进行理论计算。计算结果表明，未掺杂CrSi2是间接带隙半导体，其禁带宽度为0.392 eV，掺杂Ce元素，仍然是间接半导体，带隙宽度下降为0.031eV。未掺杂CrSi2在费米能级附近主要由Cr-5d、Si-3p态贡献。Ce掺杂后在费米能级附近主要由Cr-5d轨道，Ce-4f轨道，C-2p，Si-3p轨道贡献，掺杂后电导率提高。未掺杂CrSi2有两个介电峰，掺杂后，只有一个介电峰。未掺杂CrSi2，在能量为6.008处吸收系数达到最大值，掺杂后在能量为5.009eV处，吸收系数达到最大值。     

La单掺4H-SiC电子结构和光学性质的第一性原理研究

采用基于密度泛函理论的第一性原理计算方法，对未掺杂及La掺杂4H-SiC的电子结构和光学性质进行理论计算。计算结果表明，未掺杂4C-SiC其禁带宽度为2.257 eV。La掺杂后带隙宽度下降为1.1143eV，导带最低点为G点，价带最高点为F点，是P型间接半导体。掺杂La原子在价带的低能区间贡献比较大，而对价带的高能区和导带的贡献比较小。未掺杂4H-SiC在光子能量为6.25 eV时，出现一个介电峰，这是由于价带电子向导带电子跃迁产生。而La掺杂后，出现3个介电峰，分别对应的光子能量为0.47eV、2.67eV、6.21eV，前两个介电峰是由于价带电子向杂质能级跃迁产生，第三个介电峰是由于价带电子向导带电子跃迁产生。La掺杂后4H-SiC变成负介电半导体材料。未掺杂4h-SiC的静态介电常数为2.01，La掺杂的静态常数为12.01。     

Ce掺杂6H-SiC电子结构和光学性质的第一性原理研究

采用基于密度泛函理论的第一性原理计算方法,对未掺杂及Ce掺杂6H-SiC的电子结构和光学性质进行理论计算.计算结果表明,未掺杂6H-SiC是间接带隙半导体,其禁带宽度为2.045 eV,掺杂Ce元素,带隙宽度下降为0.812 eV.未掺杂6H-SiC在价带的低能区,Si-3s、C-2s电子轨道对态密度的贡献较大,在价带的高能区,主要是由Si-3p、Si-3s、C-2p态组成.掺杂后Ce原子的4f轨道主要贡献在导带部分,掺杂后电导率提高.未掺杂时,只有一个介电峰,是价带电子跃迁到导带电子所致,掺杂后有两个介电峰,第一个介电峰是由于导带电子跃迁到Ce原子4f轨道上产生,第二个峰是价带电子向导带电子跃迁产生.未掺杂6H-SiC,在能量为10.31 eV处吸收系数达到最大值,掺杂后在能量为6.57 eV处,吸收系数达到最大值.     

Palladium and Ruthenium Dual-Single-Atom Sites on Porous Ionic Polymers for Acetylene Dialkoxycarbonylation: Synergetic Effects Stabilize the Active Site and Increase CO Adsorption

Heterogeneous single-metal-site catalysts usually suffer from poor stability, thereby limiting industrial applications. Dual Pd₁−Ru₁ single-atom-sites supported on porous ionic polymers (Pd₁−Ru₁/PIPs) were constructed using a wetness impregnation method. The two isolated metal species in the form of a binuclear complex were immobilized on the cationic framework of PIPs through ionic bonds. Compared to the single Pd- or Ru-site catalyst, the dual single-atom system exhibits higher activity with 98 % acetylene conversion and near 100 % selectivity to dialkoxycarbonylation products, as well as better cycling stability for ten cycles without obvious decay. Based on DFT calculations, it was found that the single-Ru site exhibited a strong CO adsorption energy of −1.6 eV, leading to an increase in the local CO concentration of the catalyst. Notably, the Pd₁−Ru₁/PIPs catalyst had a much lower energy barrier of 2.49 eV compared to 3.87 eV of Pd₁/PIPs for the rate-determining step. The synergetic effect between neighboring single sites Pd₁ and Ru₁ not only enhanced the overall activity, but also stabilized Pd^II active sites. The discovery of synergetic effects between single sites can deepen our understanding of single-site catalysts at the molecular level.     

玻恩和沃尔夫合著的《光学原理》一书写作过程

《光学原理》(Principles of Optics)一书是玻恩与沃尔夫合著的、倍受好评的光学经典名著。回顾、梳理与品味这一名著的撰写过程，会得到诸多感悟。教书育人、著书立说的物理教育家以及物理学家，都可以从中得到一把尺子，用以衡量自己的工作。这有利于中国物理学的发展。     

Green chemistry and sustainability metrics in the pharmaceutical manufacturing sector

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理工科专业基础核心课程思政教学实践——以化工原理课程为例

The principles of chemical engineering is the foundation of chemical engineering professional core courses. This article introduces the goal and content of course Ideology and politics for principles of chemical engineering course. Ideological education has been carried out on the teachers' quality, knowledge, cases, historical personages, and teaching practice to provide reference for education in science and engineering course.     

Parallel and bootstrapped stochastic approximation

Parallelization of stochastic approximation procedures can reduce computation and total observation time of a system. Concerning the number of all observations used by the pure sequential and the suggested parallel method a weak invariance principle implies the asymptotic equivalence of both methods. A loglog invariance principle and a rate of a.s. convergence result describe the pathwise properties. Due to the parallel design asymptotic confidence regions can readily be constructed either by computing the bootstrap distribution or the Gaussian limit distribution determined by the empirical covariance     

Size exclusion chromatography – A blessing and a curse of science and technology of synthetic polymers

Size exclusion chromatography, SEC is one of the most popular methods for the separation of different kinds of macromolecules. This critical review gives concise information about macromolecules and their behavior in solution, basic understanding about principles, instrumentation, and application possibilities of SEC, and more in detail discusses drawbacks and pitfalls of the method with the emphasis on synthetic polymers. Selected practical advices are included to help enhance the quality of SEC results.     

La掺杂6H-SiC电子结构和光学性质的第一性原理研究

采用基于密度泛函理论的第一性原理计算方法,对未掺杂及La掺杂6H-SiC的电子结构和光学性质进行理论计算.计算结果表明,未掺杂6H-SiC是间接带隙半导体,其禁带宽度为2.045 eV,掺杂La元素,形成P型间接半导体,带隙宽度下降为0.886 eV.未掺杂6H-SiC在价带的低能区,Si-3s、C-2s电子轨道对态密度的贡献较大,在价带的高能区,主要是由Si-3p、Si-3s、C-2p态组成.掺杂后La的5d轨道与6H-SiC的sp~3轨道杂化主要贡献在价带部分,而对导带的贡献相对较小,掺杂后电导率提高.未掺杂时,只有一个介电峰,是价带电子跃迁到导带电子所致,掺杂后有两个介电峰,其中第一个介电峰是由sp~3杂化轨道上的电子跃迁到La原子5d轨道上产生.未掺杂6H-SiC,在能量为10.31处吸收系数达到最大值,掺杂后在能量为7.35 eV处,吸收系数达到最大值.