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91.
Da-Jun Zhang Shao-Hua Luo Jun Zhang 《Particle & Particle Systems Characterization》2023,40(8):2300019
The nanosized rod-like LiMnPO4/C cathode materials have successfully in situ synthesized on the surface of flaky structure MnPO4 · H2O self-sacrificing template by the hydrothermal method. The crystal microstructure, micro shape, and electrochemical parameters of LiMnPO4/C are comprehensively studied by XRD, SEM, TEM, and electrochemical measurement methods. The physical and chemical properties analysis confirms that the vinyl acetate solution (VAc-H2O) with a proper molar ratio is beneficial to generate orthorhombic olivine structure LiMnPO4 with microporous structure and nanorod-shaped morphology. The electrochemical measurement results indicate that LMP-X1-AA sample delivers an initial discharge capacity of 148.1 mAh g−1 at 0.05 C, the capacity retention rate still maintains at 89.2% after 200 cycles. As the discharge rate increases to 1 C, the discharge capacity still remains at 133.4 mAh g−1. The results indicate that the synergistic effect of nanosized rod-like morphology and conductive carbon coating is beneficial to improving the lithium ions diffusivity and electrochemical properties of LiMnPO4 materials. 相似文献
92.
Xizhang Luo Jiancong Luo Jiayin Qin 《International Journal of Infrared and Millimeter Waves》1999,20(6):1085-1090
The effect of buffer gas N2 on miniature optically pumped NH3 submillimeter wave (SMMW) cavity laser emission at 67.2m was studied theoretically and experimentally. It has been found that: 1. N2 had a positive effect on laser output of 67.2m, 2. sharp absorption in laser spectrum under certain gases mixture pressure corresponded to the threshold of 'bottleneck effect. 相似文献
93.
Based on the change of diffraction pattern, a microfluidic chip electrophoresis detection system is developed. Using tris(hydroxymethyl)aminomethane
(Tris) of 10 mmol/l as buffer and sucrose solutions (with concentration of 0.054, 0.1725, 0.24775 and 0.2975 g/ml respectively)
as samples, quantity as tiny as 55 pl (pico-liter) of sucrose solution in the microfluidic chip (with a channel diameter of
60 μm) is detected successfully with an unfocused He-Ne laser beam (633 nm, 1 mW). The experiment is simple and the detection
result is obvious.
PACS 42.25.Fx; 82.45.h; 42.66.Lc 相似文献
94.
95.
Dan-Li Hong Dr. Yang-Hui Luo Xiao-Tong He Zi-Yue Zheng Shan Su Jia-Ying Wang Cong Wang Chen Chen Prof. Bai-Wang Sun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(37):8805-8812
Precise revealing the mechanisms of excited-state intermolecular proton transfer (ESPT) and the corresponding geometrical relaxation upon photoexcitation and photoionization remains a formidable challenge. In this work, the compound (E)-4-(((4H-1,2,4-triazol-4-yl)imino)methyl)-2,6-dimethoxyphenol (TIMDP) adopting a D-π-A molecular architecture featuring a significant intramolecular charge transfer (ICT) effect has been designed. With the presence of perchloric acid (35 %), TIMDP can be dissolved through the formation of a HClO4–H2O–OH(TIMDP)–N(TIMDP) hydrogen-bonding bridge. At the ground state, the ICT effect is dominant, giving birth to crystals of TIMDP. Upon external stimuli (e.g., UV light irradiation, electro field), the excited state is achieved, which weakens the ICT effect, and significantly promotes the ESPT effect along the hydrogen-bonding bridge, resulting in crystals of [HTIMDP]+ ⋅ [H2O] ⋅ [ClO4]−. As a consequence, the mechanisms of the ESPT can be investigated, which distorted the D-π-A molecular architecture, tuned the emission color with the largest Stokes shift of 242 nm, and finally, high photoluminescence quantum yields (12 %) and long fluorescence lifetimes (8.6 μs) have achieved. These results not only provide new insight into ESPT mechanisms, but also open a new avenue for the design of efficient ESPT emitters. 相似文献
96.
Dr. Wenyan Hao Yuchen Sha Dr. Yi Deng Yi Luo Li Zeng Shan Tang Dr. Yue Weng Prof. Dr. Chien-Wei Chiang Prof. Dr. Aiwen Lei 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(19):4931-4934
An in situ generated oxidation species of nickel quinolinylpropioamide intermediate was produced. Characterization by X-ray absorption near edge structure (XANES) and EPR provides complementary insights into this oxidized nickel species. With aliphatic amides and isocyanides as substrates, a nickel-catalyzed facile synthesis of structurally diverse five-membered lactams could be achieved. 相似文献
97.
BinBin Xiao NaiZhou Wang Chao Shang FanBao Meng JianWen Ding Bin Lei XiGang Luo 《中国科学:物理学 力学 天文学(英文版)》2019,(4)
The origin of the ~40 and ~30 K superconducting phases in the metal-intercalated FeSe superconductors is still unclear. We report the synthesis of K_(0.3)(NH_3)_y(FeSe_(1-x)Te_x)_2 and K_(0.6)(NH_3)_y(FeSe_(1-x)Te_x)_2 with x=0-0.6 by using the liquid ammonia method at room temperature. The superconducting transition temperature Tcof the former remains about 43 K for all the nominal Te content less than 0.3, while that of the latter is about 30 K and obviously decreases with Te doping. Superconductivity disappears for x ≥0.4 in both systems. Except for the different chemical pressure induced by substitution of Te for Se in both systems, we also observed distinct external pressure effect on superconductivity for both systems, with much more efficiency of suppressing Tcby external pressure in the former system. These dramatic differences of both chemical and external pressure effects on Tc between the ~30 and ~40 K superconducting phases revealed that the existence of the two superconducting phases can be ascribed to the moderate and negligible coupling between FeSe layers, respectively. 相似文献
98.
YongGuang Tu GuoNing Xu XiaoYu Yang YiFei Zhang ZhaoJie Li Rui Su DeYing Luo WenQiang Yang Ying Miao Rong Cai LuHua Jiang XiaoWei Du YanChu Yang QianShi Liu Yang Gao Shuai Zhao Wei Huang QiHuang Gong Rui Zhu 《中国科学:物理学 力学 天文学(英文版)》2019,(7)
<正>The metal halide perovskite materials demonstrate outstanding performance in photovoltaics because of their excellent optoelectronic properties [1-7]. The perovskite solar cells (PSCs) exhibiting outstanding efficiency [8,9], high power-per-weight [10], and excellent radiation resistance[11-13] are considered to be promising for developing the new-generation energy technology for space application.However, the extreme space environment would impose 相似文献
99.
Transport in Porous Media - Compositional displacements in porous media, where chemical components partition between phases during a displacement, occur in flow processes such as surfactant... 相似文献
100.
Nonlinear Dynamics - A finite element model of the cantilever combined support rotor included two discs established in this paper to predict and explain the nonlinear vibration phenomenon. The... 相似文献