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131.
Frija LM Reva I Ismael A Coelho DV Fausto R Cristiano ML 《Organic & biomolecular chemistry》2011,9(17):6040-6054
Mechanisms of thermal isomerization of allyl tetrazolyl ethers derived from the carbocyclic allylic alcohols cyclohex-2-enol and 3-methylcyclohex-2-enol and from the natural terpene alcohol nerol were investigated. In the process of the syntheses of the three 1-aryl-5-allyloxytetrazoles, their rapid isomerization to the corresponding 1-aryl-4-allyltetrazol-5-ones occurred. The experiments showed that the imidates rearrange exclusively through a [3,3']-sigmatropic migration of the allylic system from O to N, with inversion. Mechanistic proposals are based on product analysis and extensive quantum chemical calculations at the DFT(B3LYP) and MP2 levels, on O-allyl and N-allyl isomers and on putative transition state structures for [1,3']- and [3,3']-sigmatropic migrations. The experimental observations could be only explained on the basis of the MP2/6-31G(d,p) calculations that favoured the [3,3']-sigmatropic migrations, yielding lower energies both for the transition states and for the final isomerization products. 相似文献
132.
V.V. Vasilyev A.V. Predein V.S. Varavin N.N. Mikhailov S.A. Dvoretsky J.V. Gumenjuk-Sichevska A.G. Golenkov V.P. Reva I.V. Sabinina Yu.G. Sidorov A.O. Susliakov F.F. Sizov A.L Aseev 《Opto-Electronics Review》2010,18(3):332-337
The long wavelength (8–12 μm) IR FPA 288×4 based on a hybrid assembly of n+-p diode photosensitive arrays (PA) of HgCdTe (MCT) MBE-grown structures and time delay integration (TDI) readout integrated circuits (ROIC) with bidirectional scanning have been developed, fabricated, and investigated. The p-type MCT structures were obtained by thermal annealing of as-grown n-type material in inert atmosphere. The MCT photosensitive layer with the composition 0.20–0.23 of mole fraction of CdTe was surrounded by the wide gap layers to decrease the recombination rate and surface leakage current. The diode arrays were fabricated by planar implantation of boron ions into p-MCT. The typical dark currents were about 4–7 nA at the reverse bias voltage of 150 mV. The differential resistance R was up to R0 = 1.6×107 Ω zero bias voltage, which corresponded to R0A ~70 Ω ·cm2 and to the maximal value Rmax = 2.1 × 108 Ω. The bidirectional TDI deselecting ROIC was developed and fabricated by 1.0-μm CMOS technology with two metallic and two polysilicon layers. The IR FPAs were free of defect channels and have the average values of responsivity Sλ = 2.27×108 V/W, the detectivity Dλ * = 2.13 × 1011 cm × Hz1/2 × Wt1, and the noise equivalent temperature difference NETD = 9 mK. 相似文献
133.
M. I. Bryzgunov A. V. Bubley A. P. Denisov V. V. Parkhomchuk V. M. Panasyuk V. B. Reva A. M. Batrakov T. V. Bedareva E. A. Bekhtenev A. D. Goncharov K. M. Gorchakov I. A. Gusev B. A. Dovzhenko A. A. Zharikov G. V. Karpov V. V. Kolmogorov M. N. Kondaurov V. Ya. Korchagin N. S. Kremnev V. A. Polukhin A. A. Putmakov D. V. Senkov M. G. Fedotov V. A. Chekavinskiy 《Physics of Particles and Nuclei Letters》2018,15(7):758-761
The electron cooling system for the NICA booster has been under construction and tested over the last few years at the Institute of Nuclear Physics. The design of this setup and the results of tests are detailed. 相似文献
134.
V. V. Parkhomchuk M. I. Bryzgunov A. V. Bubley A. D. Goncharov A. P. Denisov N. S. Kremnev V. A. Polukhin A. A. Putmakov V. B. Reva D. N. Skorobogatov 《Physics of Particles and Nuclei Letters》2018,15(7):793-797
The design and capabilities of the electron cooling system for the NICA collider are discussed. This system should suppress the intrabeam scattering and beam–beam interactions. 相似文献
135.
Self-consistent computations of the monovacancy formation energy are performed for Na N , Mg N , and Al N (12 < N ≤ 168) spherical clusters in the drop model for stable jelly. Scenarios of the Schottky vacancy formation and “bubble vacancy blowing” are considered. It is shown that the asymptotic behavior of the size dependences of the energy for the vacancy formation by these two mechanisms is different and the difference between the characteristics of a charged and neutral cluster is entirely determined by the difference between the ionization potentials of clusters and the energies of electron attachment to them. 相似文献
136.
Xi?Chen Zheng-Zhe?LinEmail authorView authors OrcID profile 《Journal of nanoparticle research》2018,20(5):136
In recent years, two-dimensional confined catalysis, i.e., the enhanced catalytic reactions in confined space between metal surface and two-dimensional overlayer, makes a hit and opens up a new way to enhance the performance of catalysts. In this work, graphdiyne overlayer was proposed as a more excellent material than graphene or hexagonal boron nitride for two-dimensional confined catalysis on Pt(111) surface. Density functional theory calculations revealed the superiority of graphdiyne overlayer originates from the steric hindrance effect which increases the catalytic ability and lowers the reaction barriers. Moreover, with the big triangle holes as natural gas tunnels, graphdiyne possesses higher efficiency for the transit of gaseous reactants and products than graphene or hexagonal boron nitride. The results in this work would benefit future development of two-dimensional confined catalysis. 相似文献