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Chinese Journal of Structural Chemistry 2019年第5期38卷 688-694,667页

作者： LIU Tao JIA Jin-Zhang LI Bu-Tong gao ke Department of Basic Teaching Liaoning Technical University Huludao 125105 China College of Safety Science and Engineering Liaoning Technical University Huludao 125105 China key Laboratory of Mine Thermo-motive Disaster and Prevention Ministry of Education Huludao 125105 China College of Mining and Technology Liaoning Technical University Huludao 125105 China

The packed density, detonation velocities, and detonation pressures of a series of cyclopropane derivatives were investigated to look for high energy density compounds. For exploring the possibility of synthesis, the bond order, heats of formation(HOF), bond dissociation energy(BDE), and characteristic height were calculated. Based on our results, A3 has the best detonation characters. Both A1 and A2 showed comparative detonation parameters and compact sensitivity with RDX, and could be regarded as the candidates of high energy density *** the heats of formation and explosive heats rose with the increase of nitrimino groups and the strain energy of three-membered ring. For A1 compound, pyrolysis mechanism might be a mix one(breakages of C–C and N–NO2 bonds). However, for A2 and A3 compounds, the N–NO2 is the trigger bond in explosive reactions. Our results may provide the basic information for further study of this kind of compounds.

关键词： high energy density compounds cyclopropane derivatives detonation performance atomization reaction

Design of terahertz band-stop filter based on a metallic resonator on high-resistivity silicon wafer

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Science China(Technological Sciences) 2013年第9期56卷 2238-2242页

作者： ZHANG JinLing ZHANG Yu gao ke Du YuLei ZHANG Nan LU YingHua School of Electronic Engineering Beijing University of Posts and Telecommunications

In this paper, we present a terahertz (THz) band-stop filter realized by fabricating a metallic T-shaped resonator pattern on the high-resistivity silicon wafer. The filter exhibits two typical band-stop response characteristics depending on the incident direction of electric field with respect to the T-shaped resonator. When the long and the short arms of the T-shaped resonator were electrically polarized by changing the incident THz wave transmission directions, the corresponding central frequencies of the band-stop filter were found to be 0.436 THz at 42dB and 0.610 THz at 28 dB, respectively. Using three-dimensional (3D) finite-integral time-domain simulations, the band-stop filter was designed, which can operate in the wavelength between 0.2 and 0.8 THz. Experimental verification was also performed using a free space THz time-domain spectroscopy system. The band-stop response characteristics are in good agreement with the simulation results. The interesting THz band-stop filtering properties suggest a promising application in the modern THz communication systems, THz time-domain spectroscopic imaging and THz continuous wave imaging.

关键词： band-stop filter finite-integral time-domain terahertz filter T-shaped resonator terahertz time-domain spectroscopy

Silane or Siloxane-Side-Chain Engineering of Photovoltaic Materials for Organic Solar Cells

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Chinese Journal of Chemistry 2023年第24期41卷 3703-3713页

作者： Qian Wang Xu Zhang Wentao Zou Huajun Xu Yuanyuan Kan Yanna Sun ke gao Shandong Provincial key Laboratory for Science of Material Creation and Energy Conversion Science Center for Material Creation and Energy ConversionInstitute of Frontier and Interdisciplinary ScienceShandong UniversityQingdaoShandong266237 China

With the tactful material design,skillful device engineering,and in-depth understanding of morphology optimization,organic solar cells (OSCs) have achieved considerable ***,OSCs have reached high power conversion efficiencies (PCEs) exceeding 19%.Especially,continuously emerging new materials have been considered as one of the key factors to improve the PCEs of *** molecular design strategies,side-chain engineering is an easy and commonly-used means which can optimize the solubility,alter intermolecular stacking arrangement,fine-tune the open circuit voltage (VOC),thus ultimately improve the *** hybrid side chains,silane and siloxane side chains have considerable effects,not only in increasing the carrier mobility and tuning the energy level,but also in affecting the crystallinity and molecular *** this review,the latest developments in photovoltaic materials based on silane and siloxane side chains are presented to illustrate the structure-property *** review comprehensively includes silane-side based polymer/small molecule donors;siloxane-side based polymer/small molecule donors,and polymer/small molecule *** the similarities and differences between these two side chains are ***,the possible applications and future prospects of silane and siloxane side chains are presented.

关键词： Organic solar cell Silane side chain Siloxane side chain Side chain engineering High performance Batteries Applications

Effects of Bionic Units in Different Scales on the Wear Behavior of Bionic Impregnated Diamond Bits

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Journal of Bionic Engineering 2016年第4期13卷 659-668页

作者： Zhaozhi Wang ke gao Youhong Sun Zhihui Zhang Shiyu Zhang Yunhong Liang Xiujuan Li Luquan Ren key Laboratory of Bionic Engineering (Ministry of Education China) Jilin University Changchun 130022 China College of Biological and Agrieultural Engineering Jilin University Changehun 130022 China College of Construction Engineering Jilin University Changchun 130026 China

Based on anti-wear theory of soil animals, the samples of impregnated diamond bit with bionic self-regenerated non-smooth surface were designed and fabricated. Such a bionic surface was characterized by concave-shape units of different scales that continuously maintained their shape and function during the whole working process. Abrasion tests were carried out to investigate the performance of samples. Results showed that the bionic samples exhibit excellent wear resistance and drilling performance under the action of bionic self-regenerated units, especially those with units of 2 mm - 3 mm diameter. The par- ticle-trapping mechanism coming from the self-regenerated concaves and the lubricating mechanism coming from the con- tinuously self-supplying of solid lubricant are important reasons for reducing or even avoiding the severe abrasions. The im- proved drilling performance of bionic samples derives from, on the one hand, the back edge of bionic unit that contributes to exposing new diamond and supplying additional shear stresses to increase the cutting ability, on the other hand, the enhanced load per unit area due to the decreased contact area at the frictional interface. The relationship between the wear behavior and the scale of bionic unit was revealed. The unit of smaller scale on the bionic samples can enhance the shear stress level. Further reducing the scale to a contain extent will diminish the wear resistance of sample. While increasing the scale can lead to the poor lubricating effect.

关键词： bionic non-smooth surface scale of bionic units impregnated diamond bits wear behavior

Charge Transfer for Reactions of Sc^(3+) with N_(2) and H_(2) at Electron-volt Energy

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Chinese Physics Letters 2001年第4期18卷 528-530页

作者： JIANG Yu-Rong NIE Zong-Xiu LI Jiao-Mei gao ke-Lin Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071

The charge transfer rate coefficients for reactions of Sc^(3+)with N_(2) and H_(2) have been measured at the mean collision energy of *** rate coefficients are derived from the decay rate of ion signals by using ion storage in a radio-frequency ion *** rate coefficients are 8.18(0.18)×10^(-10)cm^(3)·s^(-1) at Tequiv≈1.26×10^(4)K for Sc^(3+) with N_(2) and 1.44(0.39)×10^(-9)cm^(3)·s^(-1) at Tequiv>≈1.67×10^(3) K for Sc^(3+) with H_(2),*** results are comparable with the Langevin rate coefficients.

关键词： coefficients Electron H_

The role of halogen bonding in improving OFET performance of a naphthalenediimide derivative

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Chinese Chemical Letters 2018年第3期29卷 423-428页

作者： Jing Li Yong-Hui Hu Cong-Wu Ge He-Gui Gong Xi-ke gao Department of Chemistry College of Science Shanghai University key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic Chemistry Chinese Academy of Sciences

Controlling microstructure and thin film morphology of organic semiconductors by supramolecular arrangement is critical to improving their device performance. To realize well-controlling supramolecular assembly, a core-expanded naphthalene diimides derivative （1） was designed and synthesized as an n-type organic semiconductor and also as a halogen bonding （XB） donor that could form complementary XBs with 2,2-dipyridine or 2,2-bipyrimidine acceptor. The XB interactions in the solid state of 1/2,2- dipyridine and 1/2,2-bipyrimidine were confirmed by a series of characterization methods, such as thermal gravimetric analysis （TGA）, X-ray photoelectron spectroscopy （XPS）, nuclear magnetic resonance （NMR） involving 13F NMR and solid-state 13C NMR. Organic field-effect transistors （OFETs） based on XB complexes 1/2,2-dipyridine or 1/2,2-bipyrimidine showed better device performance than that of devices based on pure 1, with the average electron mobility increased more than doubled （from 0.027cm2V-1 s-1 to 0.070cm2V-1 s-1）.

关键词： Supramolecular assembly Halogen bond Naphthalene diimide Organic semiconductor Organic field-effect transistor

CR–RSS location algorithm for primary user in cognitive radio

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The Journal of China Universities of Posts and Telecommunications 2014年第1期21卷 22-25,35页

作者： YU Yin-hui SUN Chen QIN Nan-nan gao ke CHEN Deng-zhao College of Communication Eng. Jilin University Jilin branch of China telecom co. LTD

This article introduces the classic locating method based on the receiving signal strength in the cognitive radio and puts forward a cognitive radio-receiving signal strength（CR-RSS） localization algorithm which solves the problem of secondary users locating the primary user and succeeds in estimating the primary user＇s location and transmission power. Through the establishment of cognitive radio network, evaluating the number of secondary users,sampling and the environmental factors to the results in CR-RSS approach. The consequence shows that this approach can effectively locate the primary user and the technology of localization in cognitive radio can assist network optimization.

关键词： cognitive radio Location of the primary user secondary user RSS location algorithm

Study on End-to-End Web Performance

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The Journal of China Universities of Posts and Telecommunications 2004年第Z1期11卷 70-75页

作者： gao ke-li DAI Li-zhong Beijing University of Posts and Telecommunications Beijing 100876 P.R.China Beijing University of Posts and Telecommunications Beijing 100876 P.R.China

While there are lots of papers discussing one or more aspects of web performance, there are few papers talking of web performance as a whole. This paper most thoroughly discusses aspects that influence web performance and current known web techniques. In addition, we discussed the general methods of web performance measurement and explained the discrepancies between our results and those of others. Finally, we analyzed the bottlenecks of web and come up with possible solutions.

关键词： Web performance CDN HTTP DNS

Simulation and experiment of the cooling effect of trapped ion by pulsed laser

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Chinese Physics B 2021年第7期30卷 226-233页

作者： Chang-Da-Ren Fang Yao Huang Hua Guan Yuan Qian ke-Lin gao State key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China key Laboratory of Atomic Frequency Standards Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China

We investigate the process of pulsed laser cooling using a self-constructed molecular dynamics simulation(MDSimulation)*** simulate the Doppler cooling process and pulsed laser Doppler cooling process of a single^(40)Ca^(+)ion,and the comparison with the experimental results shows that this self-constructed MD-Simulation program works well in the weak laser intensity ***,we analyze the pulsed laser Doppler cooling process of a single^(27)Al^(+)*** program can be used to analyze the molecular dynamic process of various situations of Doppler cooling in an ion trap,which could give predictions and experimental guidance.

关键词： doppler cooling pulsed laser cooling molecular dynamics simulation

Atomic modeling for the initial stage of chromium passivation

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International Journal of Minerals,Metallurgy and Materials 2019年第6期26卷 732-739页

作者： Li-nan Zhang Xi-lin Xiong Yu Yan ke-wei gao Li-jie Qiao Yan-jing Su Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Corrosion and Protection Center Key Laboratory for Environmental Fracture(MOE)University of Science and Technology BeijingBeijing 100083China SUNCAT Center for Interface Science and Catalysis SLAC National Accelerator LaboratoryMenlo ParkCA 94025USA

The well-known anti-corrosive property of stainless steels is largely attributed to the addition of Cr,which can assist in forming an inert film on the corroding *** maximize the corrosion-resistant ability of Cr,a thorough study dealing with the passivation behaviors of this metal,including the structure and composition of the passive film as well as related reaction mechanisms,is ***,continuous electrochemical adsorptions of OH-groups of water molecules onto Cr terraces in acid solutions are investigated using DFT *** models with various surface conditions are *** is found to begin in the active region,and a fully coated surface mainly with oxide is likely to be the starting point of the passive *** calculated limiting potentials are in reasonable agreement with passivation potentials observed via experiment.

关键词： chromium acid solutions passive films interfaces modeling studies