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451.
In this article, we deal with a class of semilinear elliptic equations which are perturbations of the problems with the critical Hardy-Sobolev exponent. Some existence results are given via an abstract perturbation method in critical point theory. 相似文献
452.
Bernard L. S. Lin 《The Ramanujan Journal》2017,42(1):223-231
In this note, we establish two identities of \((q;\,q)_\infty ^8\) by using Jacobi’s four-square theorem and two of Ramanujan’s identities. As an important consequence, we present one Ramanujan-style proof of the congruence \(p_{-3}(11n+7)\equiv 0\ (\mathrm{mod\ }11)\), where \(p_{-3}(n)\) denotes the number of 3-color partitions of n. 相似文献
453.
454.
455.
Huili Zhu Zifan Hong Changjie Zhou Qihui Wu Tongchang Zheng Lan Yang Shuqiong Lan Weifeng Yang 《Frontiers of Physics》2023,18(1):13301
The interfacial properties of MoS2/4H-SiC heterostructures were studied by combining first-principles calculations and X-ray photoelectron spectroscopy. Experimental (theoretical) valence band offsets (VBOs) increase from 1.49 (1.46) to 2.19 (2.36) eV with increasing MoS2 monolayer (1L) up to 4 layers (4L). A strong interlayer interaction was revealed at 1L MoS2/SiC interface. Fermi level pinning and totally surface passivation were realized for 4H-SiC (0001) surface. About 0.96e per unit cell transferring forms an electric field from SiC to MoS2. Then, 1L MoS2/SiC interface exhibits type I band alignment with the asymmetric conduction band offset (CBO) and VBO. For 2L and 4L MoS2/SiC, Fermi level was just pinning at the lower MoS2 1L. The interaction keeps weak vdW interaction between upper and lower MoS2 layers. They exhibit the type II band alignments and the enlarged CBOs and VBOs, which is attributed to weak vdW interaction and strong interlayer orbital coupling in the multilayer MoS2. High efficiency of charge separation will emerge due to the asymmetric band alignment and built-in electric field for all the MoS2/SiC interfaces. The multiple interfacial interactions provide a new modulated perspective for the next-generation electronics and optoelectronics based on the 2D/3D semiconductors heterojunctions. 相似文献
456.
合成了五种多金属氧酸盐. 以B16小鼠黑色素瘤细胞为模型, 用噻唑蓝(MTT)法检测细胞存活率, 酶标法测定抗氧化活性和内黑色素含量及酪氨酸酶活性, 最后用分子对接模拟多金属氧酸盐和酪氨酸酶结合的机制. 研究结果表明, 两种磷钼酸(H7[P2Mo17VO62]和H8[P2Mo16V2O62])是高效的黑色素生成抑制剂, 在200 μmol/L的浓度下对黑色素合成的抑制率为74.40%和75.14%, 对细胞内酪氨酸酶活性的抑制率为35.71%和40.00%, 随着钒原子取代个数的增加, 两种抑制活性均逐渐降低. H7[P2Mo17VO62]和H8[P2Mo16V2O62]对细胞没有毒性. 两种多酸都有较好的1,1-二苯基-2-三硝基苯肼(DPPH)清除能力, IC50分别为1.683和2.800 mg/mL. 分子对接分数低于–146 kJ/mol. 综上所述, H7[P2Mo17VO62]和H8[P2Mo16V2O62]能抑制B16细胞黑色素的生成, 其机制与抑制酪氨酸酶的活性有关. 相似文献
457.
本文讨论非线性退化抛物方程u_t=△φ(u)的Cauchy问题弱解u(x,t)的正则性与几何性质.本文证明:若正数β足够大,则曲面ψ=ψ(x,t)=[φ(u)]~β是随时间t的连续变化而漂浮于空间R~(n+1)中的n维完备黎曼流形,它与实欧氏空R~n相切于低维流形(?)H_n(t),而H_u(t)={x∈R~n:u(x,t)0);函数ψ(x,t)在经典的意义下满足另一退化抛物方程. 相似文献
458.
This paper gives some relations and properties of several kinds of generalized convexity in Banach spaces. As a result, it
proves that every kind of uniform convexity implies the Banach-Sakes property, and several notions of uniform convexity in
literature are actually equivalent. 相似文献
459.
盛莉 《纯粹数学与应用数学》2010,26(2):270-274
给出了格值上下文无关文法(LCFG),Chomsky范式文法,Greibach范式文法的定义.证明了对任意的LCFG存在与之等价的Chomsky范式文法;给出了对任意的LCFG,存在与之等价的Greibach范式文法的条件.文中结论表明了LCFG的特性与其取值格的代数性质密切相关. 相似文献
460.
Li-qiong Xu 《应用数学学报(英文版)》2013,29(4):823-828
An edge e of a k-connected graph G is said to be a removable edge if G O e is still k-connected, where G O e denotes the graph obtained from G by the following way: deleting e to get G - e, and for any end vertex of e with degree k - 1 in G - e, say x, deleting x, and then adding edges between any pair of non-adjacent vertices in NG-e (x). The existence of removable edges of k-connected graphs and some properties of k-connected graphs have been investigated. In the present paper, we investigate the distribution of removable edges on a spanning tree of a k-connected graph (k ≥ 4). 相似文献