http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Ionization and Electrical Conductivity of Dense Carbon
Zhijian Fu,Xiaowei Sun,Weilong Quan 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.62 No.3
The electrical conductivity of a dense carbon plasma has been calculated by using a linear mixture rule considering various interactions among electrons, atoms, and ions in the density and temperature ranges of 10<sup>−5</sup> - 10 g cm<sup>−3</sup> and 10<sup>4</sup> - 10<sup>5</sup> K, respectively. The non-ideal Saha equation is used to obtain the plasma composition and the degree of ionization successfully. The present calculation spans from the weakly coupled, nondegenerate region to the strong coupled, degenerate domain. The calculated conductivity is in reasonable agreement with the explosive wire measurement and the quantum kinetic calculation. A nonmetal-metal transition is predicted to occur at 0.56 g cm<sup>−3</sup> at temperatures lower than 3 × 10<sup>4</sup> K based on the calculation of the electrical conductivity.
Zhijian Fu,Li-Jun Jia,JIHONG XIA,Hai-Bo Ruan,Ke Tang,Yong Pu,Zhao-Yi Zeng,Dian-Yong Tang,Bo Kong,Qi-Feng Chen 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2016 NANO Vol.11 No.6
The equilibrium structure and electronic properties of four ultrathin free-standing pentagonal and hexagonal noble metal nanowires, that is, copper nanowires (CuNWs), silver nanowires (AgNWs), gold nanowires (AuNWs) and platinum nanowires (PtNWs), have been studied comprehensively by adopting a first-principles simulation based on the density-functional theory. The staggered topologies are more stable than the eclipsed ones by analyzing the bonding energy. The staggered ones with a linear atom chain in the center of the pentagonal or hexagons topologies are the preferred structures for CuNWs and AgNWs, but the staggered ones without a linear atom chain in the center of the pentagon or hexagon are the preferred structures for AuNWs and PtNWs due to the increasing core–core repulsions. The calculated electronic band structures and density of states present that all the noble metal nanowires are metallic. The projected densities of states (PDOS) of dominant d-states and the charge density show that the narrower d-state moved to the Fermi energy and metallic bonding character for all the noble metal nanowires.
On Some Skew Constants in Banach Spaces
Yuankang Fu,Zhijian Yang,Qi Liu,Yongjin Li 경북대학교 자연과학대학 수학과 2023 Kyungpook mathematical journal Vol.63 No.2
We introduce the constants E[t, X], CNJ[X] and J[t, X] to describe the asym metry of the norm. They can be seen as the skew version of the Gao’s parameter, von Neumann-Jordan constant and Milman’s moduli, respectively. We establish basic proper ties of these constants, relating them other well known constants, and use these properties to calculate the constants for specific spaces. We then use these constants to study Hilbert spaces, uniformly non-square spaces and their normal structures. With the Banach-Mazur distance, we use them to study isomorphic Banach spaces
Some Geometric Constants Related to the Heights and Mid lines of Triangles in Banach Space
Dandan Du,Yuankang Fu,Zhijian Yang,Yongjin Li 경북대학교 자연과학대학 수학과 2023 Kyungpook mathematical journal Vol.63 No.1
In this paper, we introduce two new geometric constants related to the heights of triangles: ∆H(X) and ∆h(X, I). We also propose two new geometric constants, ∆m(X) and ∆M(X), related to the midlines of equilateral triangles, and discuss the relation between the heights and midlines in equilateral triangles. We give estimates for these geometric constants in terms of other geometric parameters, and the geometric constants are used to discuss geometric properties such as uniform non-squareness, uniform normal structure, and the fixed point property.
Zhen Sun,Guofeng Liu,Zuoling Fu,Xiangtong Zhang,Zhijian Wu,Yanling Wei 한국물리학회 2017 Current Applied Physics Vol.17 No.2
Yb3þ/Tm3þ co-doped BaGd2ZnO5 phosphors have been effectively synthesized by traditional sol-gel method. The graph of X-ray diffraction (XRD) exhibited that the obtained phosphors were pure orthorhombic phase. The morphology and composition of the samples were obtained by field emissionscanning electron microscope (FE-SEM) and the energy dispersive spectrometry (EDS). From upconversion luminance (UCL) emission spectra, the two strong blue emissions were obviously observed at 478 and 485 nm under the excitation of 980 nm. The possible energy diagram and UC mechanism were explained in detail. Optical temperature (T) sensing performances were evaluated in the temperature ranging 313 K - 573 K. And the highest sensor sensitivity calculated was 0.0055 K『1 at 323 K. Additionally, the laser excitation heating effect was also explored. The results indicated that Yb3þ/Tm3þ codoped BaGd2ZnO5 phosphors could be applied on optical temperature sensors and optical heater.