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101.
Thomas Özgün Dr. Klaus Bergander Dr. Lei Liu Dr. Constantin G. Daniliuc Prof. Dr. Stefan Grimme Dr. Gerald Kehr Prof. Dr. Gerhard Erker 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(34):11958-11961
The energy profile of a frustrated Lewis pair (FLP) dihydrogen splitting system was determined by a combined experimental kinetic and DFT study. A trimethylene‐bridged phosphane–borane FLP was converted into its endothermic H2‐cleavage product by sequential H+/H? addition. The system could be handled at low temperature, and the kinetics of the H2 elimination were determined to give a rate constant of kHH,exp(299 K)=(2.87±0.1)×10?4 s?1 in solution. The primary kinetic isotope effects were determined; for example, (kHH/kDD)exp=3.19. The system was accurately analyzed by DFT calculations. 相似文献
102.
《Comptes Rendus Mecanique》2014,342(10-11):583-594
In this paper we focus on WENO-based methods for the simulation of the 1D Quasi-Relativistic Vlasov–Maxwell (QRVM) model used to describe how a laser wave interacts with and heats a plasma by penetrating into it. We propose several non-oscillatory methods based on either Runge–Kutta (explicit) or Time-Splitting (implicit) time discretizations. We then show preliminary numerical experiments. 相似文献
103.
Ln0.5A0.5MnO3 (Ln=Lanthanide,A= Ca,Sr) Perovskites Exhibiting Remarkable Performance in the Thermochemical Generation of CO and H2 from CO2 and H2O 下载免费PDF全文
Sunita Dey Dr. B. S. Naidu Prof. C. N. R. Rao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(19):7077-7081
Perovskite oxides of the Ln0.5A0.5MnO3 (Ln=lanthanide, A=Sr, Ca) family have been investigated for the thermochemical splitting of H2O and CO2 to produce H2 and CO respectively. The amounts of O2 and CO produced strongly depend on the size of the rare earth ions and alkaline earth ions. The manganite with the smallest rare earth possessing the highest distortion and size disorder as well as the smallest tolerance factor, gives out the maximum amount of O2, and, hence, the maximum amount of CO. Thus, the best results are found with Y0.5Sr0.5MnO3, which possesses the highest distortion and size disorder. Y0.5Sr0.5MnO3 shows remarkable fuel production activity even at the reduction and oxidation temperatures as low as 1200 °C and 900 °C, respectively. 相似文献
104.
This Trends article highlights the recent advances published between 2012 and 2015 in solid-state 17O NMR for organic and biological molecules. New developments in the following areas are described: (1) new oxygen-containing functional groups, (2) metal organic frameworks, (3) pharmaceuticals, (4) probing molecular motion in organic solids, (5) dynamic nuclear polarization, and (6) paramagnetic coordination compounds. For each of these areas, the author offers his personal views on important problems to be solved and possible future directions. 相似文献
105.
106.
Calculations on polarization properties of alkali metal atoms using Dirac–Fock plus core polarization method 下载免费PDF全文
A semi-empirical atomic structure model method is developed in the framework of a relativistic case. This method starts from Dirac-Fock calculations using B-spline basis set. The core-valence electron correction is then treated in a semiempirical core polarization potential. As an application, the polarization properties of alkali metal atoms, including the static polarizabilities and long-range two-body dispersion coefficients, have been calculated. Our results are in good agreement with the results obtained from ab initio relativistic many-body perturbation method and the available experimental measurements. 相似文献
107.
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109.
Yanlong He Jianniao TianJuanni Zhang Sheng ChenYixuan Jiang Yanchun ZhaoShulin Zhao 《Analytica chimica acta》2013
In this work, an ultrasensitive fluorescent polarization immunoassay (FPIA) method based on the quantum dot/aptamer/antibody/gold nanoparticles ensemble has been developed for the detection of adenosine triphosphate (ATP). DNA hybridization is formed when ATP is present in the PBS solution containing the DNA-conjugated quantum dots (QDs) and antibody-AuNPs. The substantial sensitivity improvement of the antibody-AuNPs-enhanced method is mainly attributed to the slower rotation of fluorescent unit when QDs-labeled oligonucleotides hybridize with antibody modified the gold nanoparticle. As a result, the fluorescent polarization (FP) values of the system increase significantly. Under the optimal conditions, a linear response with ATP concentration is ranged from 8 × 10−12 M to 2.40 × 10−4 M. The detection limit reached as low as 1.8 pM. The developed work provides a sensitive and selective immunoassay protocol for ATP detection, which could be applied in more bioanalytical systems. 相似文献
110.
J. Grant Hill 《International journal of quantum chemistry》2013,113(1):21-34
The choice of basis set in quantum chemical calculations can have a huge impact on the quality of the results, especially for correlated ab initio methods. This article provides an overview of the development of Gaussian basis sets for molecular calculations, with a focus on four popular families of modern atom‐centered, energy‐optimized bases: atomic natural orbital, correlation consistent, polarization consistent, and def2. The terminology used for describing basis sets is briefly covered, along with an overview of the auxiliary basis sets used in a number of integral approximation techniques and an outlook on possible future directions of basis set design. © 2012 Wiley Periodicals, Inc. 相似文献