Guangdong Dapeng LNG cold energy utilization-C2 ++ extraction process integration

This paper makes a study of some technical and engineering aspects by using C2+ hydrocarbon separation facility at Guangdong Dapeng LNG (GDLNG) terminal. In the C2+ hydrocarbon extraction process, the cold energy contained in LNG will be utilized. In order to ensure the optimum operating conditions of the terminal and C2+ hydrocarbon extraction facility by optimizing the current operating processes of the terminal, the C2+ hydrocarbon extraction facility construction plan is proposed. We conducted numerous calculations and simulations using such specific analysis software as PRO II. Additionally available flow data are used to verify the cyclic send-out rates from the terminal, thus establishing the current and future projected load factors. This study is intended to make sure that GDLNG can continue to supply gas via the pipeline system safely without interruptions and most significantly solves the effects of flow fluctuations at the terminal gasification send-out facility on the hydrocarbons extraction, ensuring optimum pipeline operations and ensuring safe and effective means for such C2+ hydrocarbons extraction process as well. At the same time, the terminal is also in the optimum operation condition. This is very significant to the terminal safety operation and the energy conservation and emission reduction.     

A novel self-promoted Morita-Baylis-Hillman-like dimerization

While stable in CH₂Cl₂, hexane or THF, in the presence of MeOH, self-promoted dimerization of the triarylphosphine-alkene 1, a ligand for Pd-catalyzed reactions, produced an unusual racemic bis(phosphine) 2 in high yield. The reaction of 2 with Pd(dba)₂, followed by oxidative addition of p-IC₆H₄NO₂, yielded a trans-chelated Pd(II) aryl iodide complex.     

Infrared phononic nanoantennas: Localized surface phonon polaritons in SiC disks

The electromagnetic interaction of light with polar materials shows a sharp and well defined electromagnetic response in the infrared (IR) region that consists mainly of excitation of optical phonons. Similar to surface plasmons in the visible region, surface phonons can couple efficiently to infrared light in micron-sized antennas made of polar materials. We applied the boundary element method to calculating the infrared electromagnetic response of single SiC disks acting as effective infrared antennas as a function of different parameters such as disk size and thickness. We also analyzed the effect of locating a probing metallic tip near the SiC disk to scatter light in the proximity of the SiC disk, thereby obtaining new spectral peaks connected with localized modes between the tip and the SiC disk. We then further investigated their application in IR scanning probe microscopy. A near-field map of the phononic resonances enhances the understanding of the nature of the IR extinction peaks.     

碱基与氨基酸二肽间的氢键相互作用

对于碱基-蛋白质之间的相互作用,氢键的形成及断裂起着重要的作用.选取7种氨基酸二肽和3种碱基,以它们之间形成单根氢键的体系为研究对象,在ab initioB3LYP/6-311++G(d,p)水平下进行结构优化,MP2/6-311++G(d,p)水平下进行能量的计算.同时应用ABEEMσπ/MM方法优化结构和计算能量.通过改变氢键相互作用区域的静电相互作用参数kH-bond和形成氢键的氢原子与其受体原子的孤对电子之间距离Rlp,H来拟合函数kH-bond(Rlp,H).用所得函数对选取的复合物进行结合能计算,其结果与ab initio方法所得的结果符合的很好.     

First-principles study of the interactions of hydrogen with low-index surfaces of PdCu ordered alloy

PdCu catalysts play a key role in several hydrogen-involved processes. Among these reactions, the interaction of hydrogen with PdCu essentially determines the catalytic performance. However, the response of PdCu to surrounding hydrogen has been poorly investigated, especially for specific facets of PdCu at different environment. In this work, taking temperature and hydrogen pressure into account, we studied the hydrogen-surface interactions for four low-index surfaces of PdCu through first-principles calculations. It was found that H-PdCu adsorption strong relies on the facets, hydrogen coverage, and reaction environment (temperature and H-pressure). Our work highlights the importance of the environment on the nature of catalyst surfaces and reactions and offers a plausible way to investigate the interactions between gas and the surfaces of nanocatalysts in real reactions.     

镍原子链磁性质的第一原理计算

采用基于密度泛函理论的第一原理方法,研究了自由空间中的一维镍原子链的结构稳定性和电子性质.计算结果发现,镍的线性和平面之字型一维链式结构和体金属镍一样,基态都表现出铁磁性,并且从三维的金属镍到二维平面之字型结构链再到一维线性原子链,体系磁性逐渐增强.通过对两种原子链态密度的分析发现,在低维状态下镍原子链不管是直线链还是之字型结构都有很高的自旋极化率,说明一维镍原子链在自旋电子器件方面有潜在的应用前景.     

汾河二坝现状条件下设计洪水分析计算

对汾河二坝资料的一致性进行了修正,计算了汾河二坝现状条件下的设计洪水,以期为今后再建工程和河道防洪提供可参考的防洪标准.     

F原子与臭氧和甲烷反应机理的量子化学研究

用量子化学从头计算G3和G3MP2方法研究F原子与臭氧和甲烷的反应机理。优化了反应物、产物、中间体和过渡态的几何构型,研究结果表明,F原子与臭氧之间有很强的反应活性,但F原子与甲烷之间的反应活性更强,通过比较,当F原子与臭氧和甲烷竞争反应时,F原子与甲烷之间反应优先,并合理解释了大气中Cl原子是损耗臭氧的主要化学物质,而活性更强的F原子对臭氧损耗较小的原因是F原子被甲烷消耗了。     

现代价键理论研究进展

概述现代价键理论的几个主要方法,以及它们的特点和发展现状。并重点介绍了对不变行列式方法和相应的计算程序。     

NaF中F心的从头计算

在G94基础上提出了一种团簇嵌入晶格技术,并对NaF中F心缺陷进行了研究。团簇中的电子和核都处于周围无限大晶格产生的库仑场中,相应的Hartree-Fock算符进行了修改,计算出的F心光学激发能与实验值符合得较好,说明了此种嵌入技术是切实可行的。