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1.
For an integer , a graph is -hamiltonian if for any vertex subset with , is hamiltonian, and is -hamiltonian connected if for any vertex subset with , is hamiltonian connected. Thomassen in 1984 conjectured that every 4-connected line graph is hamiltonian (see Thomassen, 1986), and Ku?zel and Xiong in 2004 conjectured that every 4-connected line graph is hamiltonian connected (see Ryjá?ek and Vrána, 2011). In Broersma and Veldman (1987), Broersma and Veldman raised the characterization problem of -hamiltonian line graphs. In Lai and Shao (2013), it is conjectured that for , a line graph is -hamiltonian if and only if is -connected. In this paper we prove the following.(i) For an integer , the line graph of a claw-free graph is -hamiltonian if and only if is -connected.(ii) The line graph of a claw-free graph is 1-hamiltonian connected if and only if is 4-connected. 相似文献
2.
A new formulation of effective potential for local composite operators is given. The two-fermion condensate \(\langle \bar \Psi \Psi \rangle \) and four-fermion condensate \(\langle \bar \Psi \Psi \bar \Psi \Psi \rangle \) are calculated simultaneously in the Gross-Neveu model up to next-to-the-leading order in 1/N expansion. It is shown that factorization \(\langle \bar \Psi \Psi \bar \Psi \Psi \rangle = C_1 \langle \bar \Psi \Psi \rangle ^2 \) holds only in theN→∞ limit and the non-factorized part of \(\langle \bar \Psi \Psi \bar \Psi \Psi \rangle \) contributed by the order-1/N terms is comparable to \(C_1 \langle \bar \Psi \Psi \rangle ^2 \) when takingN=3. 相似文献
3.
利用紫外-可见吸收光谱和荧光光谱,在pH=7.4的生理条件下,研究了喹诺酮类药物(依诺沙星、环丙沙星和诺氟沙星)与铜锌超氧化物歧化酶(CuZnSOD)的相互作用。喹诺酮类药物能使CuZnSOD的荧光发生猝灭,其猝灭机理为静态猝灭。通过实验计算了不同温度下喹诺酮类药物与CuZnSOD的结合常数和结合点数。依据Frster非辐射能量转移理论,得到供体与受体间的距离。根据热力学参数确定了它们之间的主要作用力类型是静电引力。进一步证实了活体动物兔子注射环丙沙星后,血液中铜锌超氧化物歧化酶活性显著降低。 相似文献
4.
5.
Demonstration of a 4H SiC Betavoltaic Nuclear Battery Based on Schottky Barrier Diode 总被引:4,自引:0,他引:4 下载免费PDF全文
A 4H SiC betavoltaic nuclear battery is demonstrated. A Schottky barrier diode is utilized for carrier separation. Under illumination of Ni-63 source with an apparent activity of 4mCi/cm^2, an open circuit voltage of 0.49 V and a short circuit current density of 29.44nA/cm^2 are measured. A power conversion efficiency of 1.2% is obtained. The performance of the device is limited by low shunt resistance, backscattering and attenuation of electron energy in air and Schottky electrode. It is expected to be significantly improved by optimizing the design and processing technology of the device. 相似文献
6.
Hong-Jian Ji Jia-Yuan Li Shi-Fei Wu Wen-Yong Wu Chang-Liang Yao Shuai Yao Jian-Qing Zhang De-An Guo 《Molecules (Basel, Switzerland)》2021,26(1)
Twelve compounds, including two new aristolochic acid analogues with a formyloxy moiety (9–10) and 10 known aristolochic acid derivates (1–8 and 11–12), were obtained from the roots of Aristolochia contorta. Their structures were elucidated using extensive spectroscopic methods. Their cytotoxic activity in human proximal tubular cells HK-2 was evaluated by the MTT method, which has been widely used to assess cell viability. Among these molecules, compounds 3 and 9 were found to be more cytotoxic. Furthermore, molecular modeling was used to evaluate, for the first time, the interactions of compounds 3 and 9 with the target protein organic anionic transporter 1 (OAT1) that plays a key role in mediating aristolochic acid nephropathy. Structure–activity relationships are briefly discussed. 相似文献
7.
以羟丙基-β-环糊精(HP-β-CD)和L-酒石酸异丁酯(L-IBTA)分别为水相和有机相中手性选择体构成双相识别手性萃取体系, 研究其对佐匹克隆(ZPC)对映体的萃取动力学. 分别考察了搅拌速度、两相接触面积、水相中ZPC对映体浓度、水相及有机相中手性选择体浓度以及水相pH值对ZPC对映体萃取动力学的影响. 结果表明, L-IBTA萃取ZPC对映体的反应为“快反应”|对ZPC对映体反应是一级反应, 对L-IBTA反应是二级反应|对R-ZPC和S-ZPC反应速率常数分别为31.25×10-5和48.74×10-5 mol-2•m6•s-1. 萃取速率随HP-β-CD浓度的增加而降低. 以上研究结果将为手性萃取的工程设计提供参考. 相似文献
8.
Hong-Jian Feng 《Journal of magnetism and magnetic materials》2012,324(2):178-182
Ab initio calculations show that the coupling between antiferrodistortive (AFD) distortions and magnetization in perovskite Bi2FeMnO6 is prohibited to make magnetization rotate as effective Hubbard parameter is larger than 2.7 eV, where anomalies in antiferromagnetic (AFM) vectors and band gap varying with on-site Coulomb interaction can be observed. This coupling is attributed to the antisymmetric Dzyaloshinskii-Moriya interaction driven by the eg-eg states AFM interaction and charge redistribution with respect to different AFD distortions. 相似文献
9.
In previous papers, Catlin introduced four functions, denoted
,
,
, and
, between sets of finite graphs. These functions proved to be very useful in establishing properties of several classes of graphs, including supereulerian graphs and graphs with nowhere zero k-flows for a fixed integer k3. Unfortunately, a subtle error caused several theorems previously published in Catlin (Discrete Math. 160 (1996) 67–80) to be incorrect. In this paper we correct those errors and further explore the relations between these functions, showing that there is a sort of duality between them and that they act as inverses of one another on certain sets of graphs. 相似文献
10.
With graphs considered as natural models for many network design problems, edge connectivity κ′(G) and maximum number of edge-disjoint spanning trees τ(G) of a graph G have been used as measures for reliability and strength in communication networks modeled as graph G (see Cunningham, in J ACM 32:549–561, 1985; Matula, in Proceedings of 28th Symposium Foundations of Computer Science, pp 249–251, 1987, among others). Mader (Math Ann 191:21–28, 1971) and Matula (J Appl Math 22:459–480, 1972) introduced the maximum subgraph edge connectivity \({\overline{\kappa'}(G) = {\rm max} \{\kappa'(H) : H {\rm is} \, {\rm a} \, {\rm subgraph} \, {\rm of} G \}}\) . Motivated by their applications in network design and by the established inequalities $$\overline{\kappa'}(G) \ge \kappa'(G) \ge \tau(G),$$ we present the following in this paper:
- For each integer k > 0, a characterization for graphs G with the property that \({\overline{\kappa'}(G) \le k}\) but for any edge e not in G, \({\overline{\kappa'}(G + e) \ge k+1}\) .
- For any integer n > 0, a characterization for graphs G with |V(G)| = n such that κ′(G) = τ(G) with |E(G)| minimized.