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排序方式: 共有1347条查询结果,搜索用时 31 毫秒
151.
In this paper, we study the existence of at least three distinct solutions for a perturbed anisotropic discrete Dirichlet problem. Our approach is based on recent variational methods for smooth functionals defined on reflexive Banach spaces. Some examples are presented to demonstrate the application of our main results. 相似文献
152.
Shibo Liu 《Journal of Difference Equations and Applications》2013,19(11):1591-1598
Using the three critical points theorem, Clark's theorem and the Morse theory, multiple periodic solutions for non-linear difference systems involving the p-Laplacian are obtained by variational methods. 相似文献
153.
三标度AHP法在核应急决策中的应用 总被引:1,自引:0,他引:1
核事故发生时,采取正确的应急决策可以减轻事故的后果和危害.考虑到核应急决策的多目标性和模糊性,并针对传统AHP法的不足,利用三标度AHP法建立了多层次应急决策评估模型.模型较大程度的减小了评价的主观性,具有操作性强、稳定性好的特点.将模型与模糊层次模型计算结果进行比较,二者对方案的优劣排序是一致的.但模型在对最优方案的取舍上分辨率较高,对核应急决策具有实际的指导意义. 相似文献
154.
M. Schmidbauer P. Schäfer S. Besedin D. Grigoriev R. Köhler M. Hanke 《Journal of synchrotron radiation》2008,15(6):549-557
A new scattering technique in grazing‐incidence X‐ray diffraction geometry is described which enables three‐dimensional mapping of reciprocal space by a single rocking scan of the sample. This is achieved by using a two‐dimensional detector. The new set‐up is discussed in terms of angular resolution and dynamic range of scattered intensity. As an example the diffuse scattering from a strained multilayer of self‐assembled (In,Ga)As quantum dots grown on GaAs substrate is presented. 相似文献
155.
Myron W. Evans 《Physica B: Condensed Matter》2008,403(4):517-521
The simultaneous interaction of three fundamental fields is illustrated in Einstein Cartan Evans (ECE) theory with reference to the effect of gravitation on the inverse Faraday effect. The three-field interaction in this case is that of the fermionic, electromagnetic and gravitational fields. The interaction of the first two is developed in a well-defined semi-classical approximation of the ECE wave equation and the effect of gravitation incorporated through the index reduced canonical energy momentum density T. The exercise is repeated using the ECE wave equations and a general rule developed for the effect of gravitation on the fermionic, electromagnetic weak and strong fields. 相似文献
156.
We present a scheme for probabilistic remote preparation of an
entangled two-qubit state with three parties from a sender to either
of two receivers. The quantum channel is composed of a partially
entangled two-qubit state and a partially entangled three-qubit
state. We calculate the successful total probabilities of the scheme
in general and particular cases, respectively. We also calculate
total classical communication cost in a general case and two
particular cases, respectively. 相似文献
157.
158.
Extraordinary transport behavior of gases in isothermally annealed poly(4‐methyl‐1‐pentene) membranes
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Ywu‐Jang Fu Cheng‐Lee Lai Chien‐Chieh Hu Yi‐Ming Sun Shuan‐Ying Wu Jung‐Tsai Chen Shu‐Hsien Huang Wei‐Song Hung Kueir‐Rarn Lee 《Journal of Polymer Science.Polymer Physics》2016,54(22):2368-2376
Poly(4‐methyl‐1‐pentene) (PMP) membranes were modified through isothermal annealing to investigate the change of their crystalline structure and rigid and mobile amorphous fractions (RAF and MAF), assuming a three‐phase model, affected the gas transport behavior. The crystalline structure was characterized by wide‐angle X‐ray diffraction (WAXD) and small‐angle X‐ray scattering (SAXS) techniques, and the free volume properties were analyzed by positron annihilation lifetime spectroscopy. Compared with the pristine membrane, the annealed membranes show higher crystallinity; the crystals undergo partial structural change from form III to form I. The lamellar crystal thickness, rigid amorphous fraction thickness, and long period in the lamellar stacks increase with crystallinity. The annealed PMP membranes exhibit higher permeability due to the increase in larger size free volumes in MAF and higher selectivity due to the increase in smaller size free volumes in RAF, respectively. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 2368–2376 相似文献
159.
《Acta Crystallographica. Section C, Structural Chemistry》2018,74(3):256-262
Using polynuclear metal clusters as nodes, many high‐symmetry high‐connectivity nets, like 8‐connnected bcu and 12‐connected fcu , have been attained in metal–organic frameworks (MOFs). However, construction of low‐symmetry high‐connected MOFs with a novel topology still remains a big challenge. For example, a uninodal 8‐connected lsz network, observed in inorganic ZrSiO4, has not been topologically identified in MOFs. Using 2,2′‐difluorobiphenyl‐4,4′‐dicarboxylic acid (H2L) as a new linker and 1,2,4‐triazole (Htrz) as a coligand, a novel three‐dimensional CdII–MOF, namely poly[tetrakis(μ4‐2,2′‐difluorobiphenyl‐4,4′‐dicarboxylato‐κ5O1,O1′:O1′:O4:O4′)tetrakis(N,N‐dimethylformamide‐κO)tetrakis(μ3‐1,2,4‐triazolato‐κ3N1:N2:N4)hexacadmium(II)], [Cd6(C14H6F2O4)4(C2H2N3)4(C3H7NO)4]n, (I), has been prepared. Single‐crystal structure analysis indicates that six different CdII ions co‐exist in (I) and each CdII ion displays a distorted [CdO4N2] octahedral geometry with four equatorial O atoms and two axial N atoms. Three CdII ions are connected by four carboxylate groups and four trz− ligands to form a linear trinuclear [Cd3(COO)4(trz)4] cluster, as do the other three CdII ions. Two Cd3 clusters are linked by trz− ligands in a μ1,2,4‐bridging mode to produce a two‐dimensional CdII–triazolate layer with (6,3) topology in the ab plane. These two‐dimensional layers are further pillared by the L2− ligands along the c axis to generate a complicated three‐dimensional framework. Topologically, regarding the Cd3 cluster as an 8‐connected node, the whole architecture of (I) is a uninodal 8‐connected lsz framework with the Schläfli symbol (422·66). Complex (I) was further characterized by elemental analysis, IR spectroscopy, powder X‐ray diffraction, thermogravimetric analysis and a photoluminescence study. MOF (I) has a high thermal and water stability. 相似文献
160.
《Acta Crystallographica. Section C, Structural Chemistry》2018,74(9):1032-1037
A new cobalt(II) coordination polymer (CP), poly[[bis[μ6‐4‐(4‐carboxylatophenoxy)benzene‐1,3‐dicarboxylato‐κ6O1:O1:O3:O3′:O4:O4′]bis(1,10‐phenanthroline‐κ2N,N′)tricobalt(II)] 0.72‐hydrate], {[Co3(C15H7O7)2(C12H8N2)2]·0.72H2O}n, (I), is constructed from CoII ions and 4‐(4‐carboxyphenoxy)isophthalate (cpoia3−) and 1,10‐phenanthroline (phen) ligands. Based on centrosymmetric trinuclear [Co3(phen)2(COO)6] secondary building units (SBUs), the structure of (I) is a three‐dimensional CP with a (3,6)‐connected net and point symbol (42.6)2(44.62.87.102). The positions of four [Co3(phen)2(COO)6] SBUs and four cpoia3− ligands reproduce a Chinese‐knot‐shaped arrangement along the ab plane. (I) has been characterized by single‐crystal X‐ray diffraction, IR spectroscopy, powder X‐ray diffraction (PXRD) and thermostability analysis. It shows a good thermal stability from room temperature to 673 K. In addition, the temperature dependence of the magnetic properties was measured. 相似文献