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排序方式: 共有8468条查询结果,搜索用时 125 毫秒
1.
Acta Mathematica Sinica, English Series - We are interested in the existence and asymptotic behavior for the least energy solutions of the following fractional eigenvalue problem $$\left({\rm{P}}...  相似文献   
2.
Czechoslovak Mathematical Journal - We propose a lower bound sequence for the minimum eigenvalue of Hadamard product of an M-matrix and its inverse, in terms of an S-type eigenvalues inclusion set...  相似文献   
3.
Journal of Optimization Theory and Applications - In this paper, we introduce and investigate a new kind of coupled systems, called coupled variational inequalities, which consist of two elliptic...  相似文献   
4.
Ding  Q.  Yao  M.  Wu  Sh.  Zeng  M.  Xue  N.  Wu  D.  Xu  J. 《Journal of Applied Spectroscopy》2022,89(4):712-718
Journal of Applied Spectroscopy - Based on partial least squares (PLS) analysis, the effects of different smoothing points and different preprocessing methods on the accuracy and precision of the...  相似文献   
5.
An in situ generated oxidation species of nickel quinolinylpropioamide intermediate was produced. Characterization by X-ray absorption near edge structure (XANES) and EPR provides complementary insights into this oxidized nickel species. With aliphatic amides and isocyanides as substrates, a nickel-catalyzed facile synthesis of structurally diverse five-membered lactams could be achieved.  相似文献   
6.
We study ground states of two-component Bose–Einstein condensates (BEC) with trapping potentials in R2, where the intraspecies interaction (?a1,?a2) and the interspecies interaction ?β are both attractive, i.e, a1, a2 and β are all positive. The existence and non-existence of ground states are classified completely by investigating equivalently the associated L2-critical constraint variational problem. The uniqueness and symmetry-breaking of ground states are also analyzed under different types of trapping potentials as ββ?=a?+(a??a1)(a??a2), where 0<ai<a?:=6w622 (i=1,2) is fixed and w is the unique positive solution of Δw?w+w3=0 in R2. The semi-trivial limit behavior of ground states is tackled in the companion paper [12].  相似文献   
7.
This contribution investigates thermal decomposition of leucine, as a representative model compound for amino acids in algal biomass. We map out potential energy surface for a wide array of unimolecular and self-condensation reactions operating in the decomposition of leucine. Decarboxylation and dehydration of leucine ensues by eliminating CO2 and –OH, respectively, from the –COOH group attached to the α-carbon. The molecular channel for deamination involves cleavage of NH2 from α-carbon of leucine. The activation energies for direct elimination of CO2, NH3, and H2O from a leucine molecule lie within 20.7 kJ/mol of each other. Activation energies for these decomposition pathways reside below the bond dissociation enthalpy of H–C(α) of 323.1 kJ/mol. The decarboxylation, deamination, and dehydration pathways, via radical-prompted pathways, systematically require lower energy barriers, in reference to closed-shell reaction corridors. Detailed computations at the CBS-QB3 level provide the Arrhenius rate parameters for the unimolecular and bimolecular reactions, and standard enthalpies of formation, standard entropies, and heat capacities for all the products and intermediates. A kinetic analysis of gas-phase reactions, within the context of a plug-flow reactor model, accounts qualitatively for the formation of major products observed experimentally in the thermal degradation of the condensed-phase leucine. Among notable N-containing species, the model predicts the prevailing of NH3 over HCN and HNCO, in addition to corresponding appreciable concentrations of amines, imines, and nitriles. Our detailed kinetic investigation illustrates a negligible contribution of the self-condensation reactions of leucine in the gas phase.  相似文献   
8.
Zhu  Hong  Zeng  Xiangbing  Han  Tianli  Li  Xuexue  Zhu  Shuguang  Sun  Bai  Zhou  Ping  Liu  Jinyun 《Journal of Solid State Electrochemistry》2019,23(7):2173-2180
Journal of Solid State Electrochemistry - Since conventional graphite-based anode possesses a low capacity, seeking for high-capacity anode candidates becomes significant for constructing emerging...  相似文献   
9.
International Journal of Theoretical Physics - A new quantum watermark algorithm is presented by combining maximum pixel difference partitioning with the least significant bit substitution...  相似文献   
10.
Guo  Peng  Huang  Caihong  Zeng  Jing  Cao  Hongjun 《Nonlinear dynamics》2022,108(2):1197-1215
Nonlinear Dynamics - This paper mainly investigates the dynamics of the non-resonant and near-resonant Hopf–Hopf bifurcations caused by the interaction of the lateral and yaw motion in a...  相似文献   
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