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71.
Alain Escassut Ta Thi Hoai An 《P-Adic Numbers, Ultrametric Analysis, and Applications》2018,10(1):12-31
Let IK be an algebraically closed field of characteristic 0 complete for an ultrametric absolute value. Following results obtained in complex analysis, here we examine problems of uniqueness for meromorphic functions having finitely many poles, sharing points or a pair of sets (C.M. or I.M.) defined either in the whole field IK or in an open disk, or in the complement of an open disk. Following previous works in C, we consider functions fn(x)fm(ax + b), gn(x)gm(ax + b) with |a| = 1 and n ≠ m, sharing a rational function and we show that f/g is a n + m-th root of 1 whenever n + m ≥ 5. Next, given a small function w, if n, m ∈ IN are such that |n ? m|∞ ≥ 5, then fn(x)fm(ax + b) ? w has infinitely many zeros. Finally, we examine branched values for meromorphic functions fn(x)fm(ax + b). 相似文献
72.
We characterize the value function and the optimal stopping time for a large class of optimal stopping problems where the underlying process to be stopped is a fairly general Markov process. The main result is inspired by recent findings for Lévy processes obtained essentially via the Wiener–Hopf factorization. The main ingredient in our approach is the representation of the β-excessive functions as expected suprema. A variety of examples is given. 相似文献
73.
O. N. Prudnikov A. V. Taĭchenachev A. M. Tumaĭkin V. I. Yudin 《Journal of Experimental and Theoretical Physics》2008,106(5):839-845
The screening of the Coulomb interaction is studied with regard to Friedel oscillations in multicomponent electron plasma structure. A double quantum well (QW) and a superlattice are considered. The groundstate energy of a donor (exciton) in a double quantum well is calculated by a variational method as a function of the population of subbands. 相似文献
74.
Jincan Zhang Kaicheng Jia Li Lin Wei Zhao Huy Ta Quang Luzhao Sun Tianran Li Zhenzhu Li Xiaoting Liu Liming Zheng Ruiwen Xue Jing Gao Zhengtang Luo Mark H. Rummeli Qinghong Yuan Hailin Peng Zhongfan Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(41):14588-14593
Contamination commonly observed on the graphene surface is detrimental to its excellent properties and strongly hinders its application. It is still a great challenge to produce large‐area clean graphene film in a low‐cost manner. Herein, we demonstrate a facile and scalable chemical vapor deposition approach to synthesize meter‐sized samples of superclean graphene with an average cleanness of 99 %, relying on the weak oxidizing ability of CO2 to etch away the intrinsic contamination, i.e., amorphous carbon. Remarkably, the elimination of amorphous carbon enables a significant reduction of polymer residues in the transfer of graphene films and the fabrication of graphene‐based devices and promises strongly enhanced electrical and optical properties of graphene. The facile synthesis of large‐area superclean graphene would open the pathway for both fundamental research and industrial applications of graphene, where a clean surface is highly needed. 相似文献
75.
Guillemin R Carniato S Stolte WC Journel L Taïeb R Lindle DW Simon M 《Physical review letters》2008,101(13):133003
Polarization-dependent resonant inelastic x-ray scattering (RIXS) is shown to be a new probe of molecular-field effects on the electronic structure of isolated molecules. A combined experimental and theoretical analysis explains the linear dichroism observed in Cl 2p RIXS following Cl 1s excitation in HCl and CF3Cl as due to molecular-field effects, including singlet-triplet exchange, indicating polarized-RIXS provides a direct probe of spin-orbit-state populations applicable to any molecule. 相似文献
76.
We obtain the exact analytical solution of the Klein-Gordon equation for the exponential vector and scalar potentials by using
the asymptotic iteration method. For the scalar potential greater than the vector potential case, the exact bound state energy
eigenvalues and corresponding eigenfunctions are presented. The bound state eigenfunction solutions are obtained in terms
of the confluent hypergeometric functions. 相似文献
77.
Nguyen H. N. Vu M. A. Hy D. M. Ta N. A. Do A. T. 《Journal of Applied and Industrial Mathematics》2021,15(2):315-325
Journal of Applied and Industrial Mathematics - In this paper, we introduce a nonlinear Lanchester-type model involving supply units. The model describes a battle where the Blue party consisting of... 相似文献
78.
The β‐Agostic Structure in (C5Me5)2Sc(CH2CH3): Solid‐State NMR Studies of (C5Me5)2Sc−R (R=Me,Ph, Et) 下载免费PDF全文
Damien B. Culver Winn Huynh Dr. Hosein Tafazolian Dr. Ta‐Chung Ong Prof. Dr. Matthew P. Conley 《Angewandte Chemie (International ed. in English)》2018,57(30):9520-9523
Multinuclear solid‐state NMR studies of Cp*2Sc?R (Cp*=pentamethylcyclopentadienyl; R=Me, Ph, Et) and DFT calculations show that the Sc?Et complex contains a β‐CH agostic interaction. The static central transition 45Sc NMR spectra show that the quadrupolar coupling constants (Cq) follow the trend of Ph≈Me>Et, indicating that the Sc?R bond is different in Cp*2Sc?Et compared to the methyl and phenyl complexes. Analysis of the chemical shift tensor (CST) shows that the deshielding experienced by Cβ in Sc?CH2CH3 is related to coupling between the filled σC‐C orbital and the vacant orbital. 相似文献
79.
Akdemir ZS Akçakaya H Kahraman MV Ceyhan T Kayaman-Apohan N Güngör A 《Macromolecular bioscience》2008,8(9):852-862
In this study, photopolymerized hydrogels of fumarated poly(ethylene glycol) diglycidyl-co- poly(ethylene glycol) diacrylate have been synthesized and modified with cell adhesion peptide, Arg-Gly-Asp (RGD). The structural and mechanical properties of the hydrogels are found to be poly(ethylene glycol) diacrylate (PEGDA) dependent. The percentage of gelation is increased from 72 to 89 wt.-% when the amount of the crosslinker co-monomer (PEGDA) in the hydrogel formulation is increased from 20 to 40 wt.-%. In the present case, the equilibrium mass swelling is decreased from 216 to 93%. The viscosities of the uncured formulations have also been measured and likewise, the results were influenced by the increasing amount of PEGDA that reduced the value from 83 to 36 cP. The compressive modulus of the prepared hydrogels was improved with the addition of the PEGDA. Cell growth experiments have been performed by comparing the properties of the hydrogels with and without RGD units. The results show that RGD units enhance the adhesion of cells to the surface of the hydrogels. SEM-EDS studies reveal that nitrogen and calcium are produced on the osteoblast-seeded surface of the scaffold within the culture time period. [Figure: see text]. 相似文献
80.
Eui Ta Choi 《Tetrahedron》2008,64(7):1515-1522
Catalytic asymmetric dehydration of β-aryl or alkyl substituted β-hydroxy esters via kinetic resolution has been investigated. A brief survey of 10 different chiral ligands is conducted to examine the effects of chiral ligand structure on selectivity of the dehydration. The kinetic resolution of a variety of rac-β-hydroxy tert-butyl esters in the presence of prolinol chiral ligand 2 and BrZnCH2CO2-t-Bu can provide highly enantioenriched β-hydroxy esters 14-21 with selectivity factors ranging from 11 to 66. Also, application of this asymmetric synthetic methodology to the preparation of enantioenriched flavane derivatives 25-29 is demonstrated. 相似文献