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81.
The experiment of separating low toxic n-hexane and cyclohexane by traditional gas chromatography was improved with orthogonal experimental design. The effect of sample quantity, vaporization chamber temperature, detector temperature, column temperature, line velocity and separability of the split ratio were examined. Through the experiment, students could understand the use and maintenance of gas chromatography instruments. At the same time, they could understand separability and column efficiency of chromatography. 相似文献
82.
83.
Maoyan Wang Jian Wu Jun Xu Debiao Ge Hailong Li Jian Feng 《International Journal of Infrared and Millimeter Waves》2008,29(2):167-178
The interaction between Gaussian beam and indefinite anisotropic metamaterial (AMM) slabs are simulated with auxiliary differential
equation method in finite-difference time-domain method (FDTD). The directions of wave vector and energy flow densities in
three types of AMM slabs are investigated. The field intensity distributions and phases of TE-polarized wave for the interaction
between Gaussian beam and AMM slabs are given. Numerical results show that the sign of x component of relative permeability tensor of AMM determines the refraction is regular or anomalous, whereas the sign of z component of relative permeability tensor of AMM determines the energy flow is positively refracted or negatively refracted.
Positive or negative Goos-H?nchen shift associated with Total Cutoff media are also shown.
This work was supported by National Key Laboratory of Electromagnetic Environment fund (51486030305HT0101) and (9140C08060507ZCZJ18). 相似文献
84.
利用一个(N 1)粒子部分纠缠Greenberger-Home-Zeilinger(GHZ)态作为量子通道,提出了概率远程制备N粒子GHZ态的两个方案.我们考虑了怎样远程制备一个任意的GHZ态,即两个参数α和β都是复数的情况.此外,计算了远程制备总的成功概率和需要的经典信息量. 相似文献
85.
HUA Cong WANG Xuanzhong LIANG Shipeng LI Chen CHEN Xi PIAO Meihua WANG Zhenchuan GE Pengfei LUO Tianfei 《高等学校化学研究》2022,38(4):1089-1096
Ferroptosis triggered by hemin is regarded as a primary factor accounting for neuronal death secondary to intracerebral hemorrhage. Thus, compounds with inhibitory effect on hemin-induced ferroptosis might be potential medicines to prevent neuronal death caused by intracerebral hemorrhage. Herein, we investigate whether maltol could alleviate hemin-induced SH-SY5Y cell ferroptosis and its potential mechanisms. It is found that maltol effectively prevents hemin-induced SH-SY5Y cell ferroptosis via three pathways. The first one is inhibiting intracellular iron increase via preventing upregulation of transferrin receptor, the second one is alleviating lipid peroxidation via attenuating H2O2 generation by NOX4 and promoting H2O2 clearance by catalase, and the third one is to reduce peroxidized lipids via maintaining GPX4/GSH pathway. Therefore, maltol is a novel agent preventing hemin-induced SH-SY5Y cell ferroptosis. 相似文献
86.
This paper deals with a variable diffusion predator–prey model with additive Allee effect. A good understanding of the existence of steady states is gained for the case . The result shows that the reduce problem has multiple solutions. Moreover, by applying the singular perturbation method, we give a proof of existence of large amplitude solutions when is sufficiently small. 相似文献
87.
Gong Hengfeng Xiao Hong Wu Hailong Meng Fanliang Ren Qisen Liao Yehong Zhang Guoliang 《The European Physical Journal B - Condensed Matter and Complex Systems》2022,95(8):1-7
The European Physical Journal B - Molecular dynamics and Monte Carlo methods are common measurements to study the diffusion coefficients of the fluid particles under restricted conditions. Here,... 相似文献
88.
提出了一款具有高隔离度的双陷波超宽带多入多出(UWB MIMO)天线。该天线由两个相同的半切超宽带天线单元倒置构成。通过在天线底板刻蚀栅栏型缺陷地解耦结构,使该MIMO天线的隔离度提高至25 dB。此外,在天线半圆形辐射贴片上刻蚀两个方向相反的"L"型缝隙,实现了双陷波的功能,分别抑制了802.16无线城域网WiMAX(3.2~3.7 GHz)和WLAN(5.15~5.85 GHz)信号对天线系统的干扰。实验结果表明,该天线在3~11 GHz工作带宽内的隔离度大于25 dB,包络相关系数(ECC)小于0.004;第一个陷波频段为3.0~3.7 GHz,第二个陷波频段为5.1~5.85 GHz,有效抑制了WiMAX和WLAN的信号干扰。 相似文献
89.
90.
Electroorganic synthesis is an emerging area of high impact research in organic chemistry, which is considered as one of the green and efficient methods and attracts growing research attention. In this review, we summarized comprehensively the recent literature reports on the electrochemical oxidative difunctionalization of unsaturated C—C bonds. The reaction types described in this review included electrochemical intermolecular cyclization, electrochemical intramolecular cyclization, and electrochemical difunctionalization of alkenes/alkynes. This review focuses on the discussion of its synthetic generality for the preparation of functionalized compounds and the related electrochemical oxidative reaction mechanism. 相似文献