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1.
Van On Vo Tran Dzung Tri Nguyen Chi Linh Phan Khiem Hong 《The European Physical Journal C - Particles and Fields》2022,82(3):1-12
The European Physical Journal C - Considering supergravity theory is a natural step in the development of gravity models. This paper follows the “algebraic“ path and constructs possible... 相似文献
2.
高温气冷堆燃料元件的基体石墨是一种多孔复合材料,是燃料元件的主要组成部分,其结构影响燃料元件的性能和裂变产物在燃料元件中的扩散。 本文利用压汞法表征基体石墨的孔隙结构,并讨论了基体石墨制备工艺中最大压制压强与热处理过程对孔隙结构的影响。 结果表明,基体石墨大孔孔径分布为6001900 nm,高温热处理使基体石墨的总孔隙率、中值孔径、大孔孔容均减小;基体石墨热处理样品的大孔孔容随最大压制压强的增加而呈线性减少,热处理过程单质Ag在石墨基体中的扩散速度与大孔孔容变化具有正相关性。 相似文献
3.
Shuangshuang Long Weijie Chi Lu Miao Qinglong Qiao Xiaogang Liu Zhaochao Xu 《中国化学快报》2019,30(3):601-604
Both experimental and computational studies showed owing to strong π-π stacking interactions, 1-acetylpyrene mainly exists in dimers and molecular aggregates even at low concentrations, which led to the mis-assignment of its monomer emission peaks. 相似文献
4.
Gitae Moon Intae Son Chunho Kim Chi Hyeong Cho Eunbi Lee Eun Hyoung Bae 《Molecular Crystals and Liquid Crystals》2019,687(1):60-67
AbstractTo enable recent 3D and moving picture applications, liquid crystal displays (LCD) must exhibit fast response and wide viewing angle characteristics. Pre-tilted vertical alignment layers for high-speed LCD were fabricated using bi-functional photoreactive monomers. The monomers can be confined to the polyimide layer and photo-polymerized by UV exposure under voltage. Response characteristics of photo-controlled alignment films according to the structure were investigated. Vertical alignment properties were evaluated using a polarizing optical microscope, and electro-optical characteristics were compared through the voltage-transmittance curve and response time measurement. Faster response speed could be obtained by using photoreactive monomers having a long alkyl chain. 相似文献
5.
Nonlinear Dynamics - The problem of self-sustained oscillations in excitable complex networks is the central issue under investigation, among which the exploration of the key factors in determining... 相似文献
6.
7.
Zongqing Chi Wenbo Dong Qingzhong Li Xin Yang Steve Scheiner Shufeng Liu 《International journal of quantum chemistry》2019,119(8):e25867
The carbene triel bond is predicted and characterized by theoretical calculations. The C lone pair of N-heterocyclic carbenes (NHCs) is allowed to interact with the central triel atom of TrR3 (Tr = B and Al; R = H, F, Cl, and Br). The ensuing bond is very strong, with an interaction energy of nearly 90 kcal/mol. Replacement of the C lone pair by that of either N or Si weakens the binding. The bond is strengthened by electron-withdrawing substituents on the triel atom, and the reverse occurs with substitution on the NHC. However, these effects do not strictly follow the typical pattern of F > Cl > Br. The TrR3 molecule suffers a good deal of geometric deformation, requiring on the order of 30 kcal/mol, in forming the complex. The R(C···Tr) bond is quite short, for example, 1.6 Å for Tr = B, and shows other indications of at least a partially covalent bond, such as a high electron density at the bond critical point and a good deal of intermolecular charge transfer. 相似文献
8.
Dr. Chaoxian Chi Dr. Sudip Pan Dr. Jiaye Jin Dr. Luyan Meng Prof. Mingbiao Luo Prof. Lili Zhao Prof. Mingfei Zhou Prof. Gernot Frenking 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(50):11772-11784
The octacarbonyl cation and anion complexes of actinide metals [An(CO)8]+/− (An=Th, U) are prepared in the gas phase and are studied by mass-selected infrared photodissociation spectroscopy. Both the octacarbonyl cations and anions have been characterized to be saturated coordinated complexes. Quantum chemical calculations by using density functional theory show that the [Th(CO)8]+ and [Th(CO)8]− complexes have a distorted octahedral (D4h) equilibrium geometry and a doublet electronic ground state. Both the [U(CO)8]+ cation and the [U(CO)8]− anion exhibit cubic structures (Oh) with a 6A1g ground state for the cation and a 4A1g ground state for the anion. The neutral species [Th(CO)8] (Oh; 1A1g) and [U(CO)8] (D4h; 5B1u) have also been calculated. Analysis of their electronic structures with the help on an energy decomposition method reveals that, along with the dominating 6d valence orbitals, there are significant 5f orbital participation in both the [An]←CO σ donation and [An]→CO π back donation interactions in the cations and anions, for which the electronic reference state of An has both occupied and vacant 5f AOs. The trend of the valence orbital contribution to the metal–CO bonds has the order of 6d≫5f>7s≈7p, with the 5f orbitals of uranium being more important than the 5f orbitals of thorium. 相似文献
9.
Ling-Yang Hsu Qiumin Liang Zhiheng Wang Hsin-Hung Kuo Wun-Shan Tai Shi-Jian Su Xiuwen Zhou Yi Yuan Yun Chi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(67):15375-15386
Iridium complexes bearing chelating cyclometalates are popular choices as dopant emitters in the fabrication of organic light-emitting diodes (OLEDs). In this contribution, we report a series of blue-emitting, bis-tridentate IrIII complexes bearing chelates with two fused five-six-membered metallacycles, which are in sharp contrast to the traditional designs of tridentate chelates that form the alternative, fused five-five metallacycles. Five IrIII complexes, Px-21 – 23 , Cz-4 , and Cz-5 , have been synthesized that contain a coordinated dicarbene pincer chelate incorporating a methylene spacer and a dianionic chromophoric chelate possessing either a phenoxy or carbazolyl appendage to tune the coordination arrangement. All these tridentate chelates afford peripheral ligand–metal–ligand bite angles of 166–170°, which are larger than the typical bite angle of 153–155° observed for their five-five-coordinated tridentate counterparts, thereby leading to reduced geometrical distortion in the octahedral frameworks. Photophysical measurements and TD-DFT studies verified the inherent transition characteristics that give rise to high emission efficiency, and photodegradation experiments confirmed the improved stability in comparison with the benchmark fac-[Ir(ppy)3] in degassed toluene at room temperature. Phosphorescent OLED devices were also fabricated, among which the carbazolyl-functionalized emitter Cz-5 exhibited the best performance among all the studied bis-tridentate phosphors, showing a maximum external quantum efficiency (EQEmax) of 18.7 % and CIEx,y coordinates of (0.145, 0.218), with a slightly reduced EQE of 13.7 % at 100 cd m−2 due to efficiency roll-off. 相似文献
10.
Kai Xu Zhenchang Tang Yan Zhang Wanshu Li Haiou Li Lihui Wang Liming Liu Honghang Wang Feng Chi Xiaowen Zhang 《Current Applied Physics》2019,19(10):1076-1081
Germanium dioxide (GeO2) aqueous solutions are facilely prepared and the corresponding anode buffer layers (ABLs) with solution process are demonstrated. Atomic force microscopy, X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy measurements show that solution-processed GeO2 behaves superior film morphology and enhanced work function. Using GeO2 as ABL of organic light-emitting diodes (OLEDs), the visible device with tris(8-hydroxy-quinolinato)aluminium as emitter gives maximum luminous efficiency of 6.5 cd/A and power efficiency of 3.5 lm/W, the ultraviolet device with 3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole as emitter exhibits short-wavelength emission with peak of 376 nm, full-width at half-maximum of 42 nm, maximum radiance of 3.36 mW/cm2 and external quantum efficiency of 1.5%. The performances are almost comparable to the counterparts with poly (3,4-ethylenedioxythiophene):poly (styrenesulfonate) as ABL. The current, impedance, phase and capacitance as a function of voltage characteristics elucidate that the GeO2 ABL formed from appropriate concentration of GeO2 aqueous solution favors hole injection enhancement and accordingly promoting device performance. 相似文献