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Effect of non-spherical atmospheric charged particles and atmospheric visibility on performance of satellite-ground quantum link and parameters simulation

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The Journal of China Universities of Posts and Telecommunications 2017年第6期24卷 39-48页

作者： shi Li Nie Min Yang Guang pei Changxing School of Communication and Information engineering Xi'an University of Posts and Telecommunication School of Electronics and Information Northwestern Polytechnical University State Key Laboratory of Integrated Service Networks Xidian University

In order to study the relationship between the non-spherical atmospheric charged particles and satellite-ground quantum links attenuation. The relationship among the particle concentration, equivalent radius, charge density of the charged particle, the attenuation coefficient and entanglement of the satellite-ground quantum link can be established first according to the extinction cross section and spectral distribution function of the non-spherical atmospheric charged particles. The quantitative relationship between atmospheric visibility and communication fidelity of satellite-ground quantum link were analyzed then. Simulation results show that the ellipsoid, Chebyshev atmospheric charged particle influences on attenuation of the satellite-ground quantum link increase progressively. When the equivalent particle radius is 0.2 gm and the particle concentration is 50 μg/m^3, the attenuation coefficient and entanglement of the satellite-ground quantum link is 9.21 dB/km, 11.46 dB/km and 0.453, 0.421 respectively; When the atmospheric visibility reduces from 8 km to 2 kin, the communication fidelity of satellite-ground quantum link decreases from 0.52 to 0.08. It is shown that the non-spherical atmospheric charged particles and atmospheric visibility influence greatly on the performance of the satellite-ground quantum link communication system. Therefore, it is necessary to adjust the parameters of the quantum-satellite communication system according to the visibility values of the atmosphere and the shapes of the charged particles in the atmosphere to improve reliability of the satellite-ground quantum link.

关键词： satellite-ground quantum link non-spherical atmospheric charged particles atmospheric visibility degree of quantum entanglement

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The transmission link of CAPS navigation and communication system

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Science China(Physics,Mechanics & Astronomy) 2009年第3期52卷 402-411页

作者： CUI JunXia shi HuLi CHen JiBin pei Jun National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China Graduate University of Chinese Academy of Sciences Beijing 100049China China Telecommunications Broadcast Satellite Co. Beijing 100083China

The Chinese Area Positioning System (CAPS) is based on communication satellites with integrated capability, which is different from the Global Positioning System (GPS), the International Maritime Satellite Organization (Inmarsat) and so on. CAPS works at C-band, and its navigation information is not directly generated from the satellite, but from the master control station on the ground and transmitted to users via the satellite. The slightly inclined geostationary-satellite orbit (SIGSO) satellites are adopted in CAPS. All of these increase the difficulty in the design of the system and terminals. In this paper, the authors study the CAPS configuration parameters of the navigation master control station, information transmission capability, and the selection of the antenna aperture of the communication center station, as well as the impact of satellite parameters on the whole communication system from the perspective of the transmission link budget. The conclusion of availability of the CAPS navigation system is achieved. The results show that the CAPS inbound communication system forms a new low-data-rate satellite communication system, which can accommodate mass communication terminals with the transmission rate of no more than 1 kbps for every terminal. The communication center station should be configured with a large-aperture antenna (about 10-15 m); spread spectrum com- munication technology should be used with the spreading gain as high as about 40 dB; reduction of the satellite transponder gain attenuation is beneficial to improving the signal-to-noise ratio of the system, with the attenuation value of 0 or 2 dB as the best choice. The fact that the CAPS navigation system has been checked and accepted by the experts and the operation is stable till now clarifies the rationality of the analysis results. The fact that a variety of experiments and applications of the satellite communication system designed according to the findings in this paper have been succ

关键词： satellite navigation satellite communication transmission link link margin demodulation threshold CAPS

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Unraveling the impacts of intermolecular interaction on morphology evolution for highly efficient organic solar cells and modules

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Science China Chemistry 2025年第01期 264-272页

作者： Xueqing Ma Yingying Cheng Yuqiang Liu Xinming Zheng Guangliu Ran Hongxiang Li Xinyue Cui Andong Zhang Wenkai Zhang pei Cheng Wenchao Huang Zhishan Bo Beijing Key Laboratory of energy Conversion and Storage Materials College of Chemistry Beijing Normal University College of Textiles and Clothing State Key Laboratory of Bio-fibers and Eco-textiles Qingdao University Key State Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of Technology Department of Physics and Applied Optics Beijing Area Major Laboratory Center for Advanced Quantum Studies Beijing Normal University State Key Laboratory of Polymer Materials engineering College of Polymer Science and Engineering Sichuan University

Understanding the effect of intermolecular interaction on the growth dynamic of active layers is critical for advancing organic solar cells(OSCs). However, the diverse structure of donors and acceptors makes the research challenging. Additives with customizable structures and properties could simplify this complexity. Herein, we meticulously tailor two additives of 3,4-ethylenedioxythiophene(EDOT) and 2,5-dibromo-3,4-ethylenedioxythiophene(DBEDOT), possessing distinct intermolecular interaction features to elaborate the inherent relationship. It is found that varied interaction strengths can alter film formation processes. The enhanced intermolecular interaction between the DBEDOT and non-fullerene acceptor BTP-e C9-4F results in pre-aggregation and longer crystallization duration of BTP-e C9-4F, facilitating the formation of films with compact molecular packing and decent phase separation. Thus, exciton dissociation and charge transport become more efficient. Finally, devices processed with DBEDOT exhibit a remarkable power conversion efficiency of 19.35% in small-area OSCs and 14.11% in bladecoated 5 cm × 5 cm organic solar mini-modules. Especially, OSCs can maintain 80% of their initial efficiency after continuous annealing at 85 °C for over 2,100 h.

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Multi-grained system integration for hybrid-paradigm brain-inspired computing

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Science China(Information Sciences) 2023年第4期66卷 272-285页

作者： Jing pei Lei DenG Cheng MA Xue LIU Luping shi Department of Precision Instrument Center for Brain Inspired Computing Research(CBICR) Beijing Innovation Center for Future Chip Tsinghua University

Hybrid neuromorphic computing supporting the prevailing artificial neural networks and neuroscience-inspired models/algorithms offers substantial flexibility for cross-paradigm model *** is one of the most promising technologies for accelerating intelligence development, ultimately contributing to artificial general intelligence development. Recently, an increasing number of hybrid neuromorphic computing chips have been reported, but such research focuses on chip design without demonstrating systems for large-scale workloads. To this end, we construct a multi-grained system based on many Tianjic chips, presenting a large-scale system for hybrid-paradigm brain-inspired computing. With different numbers of chips and different connection topologies, we develop a Tianjic card and a Tianjic board as the infrastructure for building embedded systems and cloud servers, respectively. Extensive measurements of the communication latency, computational latency, and power consumption evidence the superior potential of Tianjic systems for exploring brain-inspired computing for artificial general intelligence.

关键词： brain-inspired computing multi-grained system integration hybrid paradigm Tianjic chip brain-inspired platform

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Capture of carbon dioxide by amine-impregnated as-synthesized MCM-41

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Journal of environmental Sciences 2010年第10期22卷 1558-1563页

作者： Jianwen Wei Lei Liao Yu Xiao pei Zhang Yao shi . College of environmental Science and Technology Guangxi Key Laboratory of Environmental Engineering and Protecting Assessment Guilin University of Technology Guilin 541004 China. Department of Chemical and Biochemical engineering Zhejiang University Hangzhou 310027 China

The novel carbon dioxide （CO2） adsorbents with a high capture efficiency were prepared through impregnating the as-synthesized MCM-41 with three kinds of amines, namely diethylenetriamine （DETA）, triethylenetetramine （TETA） and 2-amino-2-methyl-1- propanol （AMP）. The resultant samples were characterized by small angle X-ray diff action and low temperature N2 adsorption. The synthesis way not only saves the energy or extractor to remove the template but also is environmentally friendly due to the absence of the potential pollutants such as toluene. CO2 capture was investigated in a dynamic packed column. The sample impregnated by TETA showed the highest adsorption capacity, approximately 2.22 mmol/g at 60℃ due to its highest amino-groups content among the three amines. The CO2 adsorption behavior was also investigated with the deactivation model, which showed an excellent prediction for the breakthrough curves.

关键词： CO2 capture as-synthesized MCM-41 impregnation deactivation model

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Numerical Prediction and Performance Experiment in a Deep-well Centrifugal Pump with Different Impeller Outlet Width

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Chinese Journal of Mechanical engineering 2013年第1期26卷 46-52页

作者： shi Weidong ZHOU Ling LU Weigang pei Bing LANG Tao National Research Center of Pumps and Pumping System engineering and Technology Jiangsu UniversityZhenjiang 212013China

The existing research of the deep-well centrifugal pump mainly focuses on reduce the manufacturing cost and improve the pump performance, and how to combine above two aspects together is the most difficult and important topic. In this study, the performances of the deep-well centrifugal pump with four different impeller outlet widths are studied by the numerical, theoretical and experimental methods in this paper. Two stages deep-well centrifugal pump equipped with different impellers are simulated employing the commercial CFD software to solve the Navier-Stokes equations for three-dimensional incompressible steady flow. The sensitivity analyses of the grid size and turbulence model have been performed to improve numerical accuracy. The flow field distributions are acquired and compared under the design operating conditions, including the static pressure, turbulence kinetic energy and velocity. The prototype is manufactured and tested to certify the numerical predicted performance. The numerical results of pump performance are higher than the test results, but their change trends have an acceptable agreement with each other. The performance results indicted that the oversize impeller outlet width leads to poor pump performances and increasing shaft power. Changing the performance of deep-well centrifugal pump by alter impeller outlet width is practicable and convenient, which is worth popularizing in the engineering application. The proposed research enhances the theoretical basis of pump design to improve the performance and reduce the manufacturing cost of deep-well centrifugal pump.

关键词： deep-well centrifugal pump impeller outlet width performance numerical simulation

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A series of novel Zn(Ⅱ) and Mn(Ⅱ) metal-organic frameworks constructed by 2,4-bis-oxyacetate-benzoic acid: syntheses, structures and photoluminescence

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Science China Chemistry 2015年第3期58卷 448-456页

作者： Yan Lv pei shi Wei Shen Xiaoju Chen Guoliang Zhao College of Chemistry and Life Science Zhejiang Normal University Xingzhi College Zhejiang Normal University

A new carboxylic acid ligand, 2,4-bis-oxyacetate-benzoic acid(H3BOABA), was designed and introduced to construct novel metal-organic framework materials. [Zn Na(BOABA)(phen)(H2O)]·H2O(1), Zn Na(BOABA)(2), Mn3(BOABA)2(phen)2(3), [Mn2(BOABA)(OH)]·(H2O)2(4)(CCDC: 885138, 885137, 894225, 883094) were hydrothermally synthesized and characterized by elemental analysis, IR spectra and thermal gravimetric analyses. Crystal structures of the complexes were determined by single crystal X-ray diffraction method. Complex 1 is a one dimensional double edges non-interpenetrated framework decorated by the phen ligands on the surface. Complex 2 is an unique three dimensional open framework, consisting of Zn(II) and Na(I). Complex 3 is an unique double edges one dimensional MOF containing a [Mn3(BOABA)2(phen)2]n non-interpenetrated structure. Complex 4 is a two dimensional plane structure containing two Mn atoms in the same coordination environment. The interaction between four complexes and DNA were studied by Et Br fluorescence probe. Meanwhile, photoluminescence studies revealed that these four complexes display strong fluorescent emission bands in the solid state at room temperature.

关键词： Zn and Mn complexes 2 4-bis-oxyacetate-benzoic acid crystal structure DNA binding photoluminescence

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Regeneration of 2-amino-2-methyl-1-propanol used for carbon dioxide absorption

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Journal of environmental Sciences 2008年第1期20卷 39-44页

作者： ZHANG pei shi Yao WEI Jianwen ZHAO Wei YE Qing Department of environmental Science Zhejiang University Hangzhou 310028 China

To improve the efficiency of the carbon dioxide cycling process and to reduce the regeneration energy consumption, a sterically hindered amine of 2-amino-2-methyl-1- propranol （AMP） was investigated to determine its regeneration behavior as a CO2 absorbent. The CO2 absorption and amine regeneration characteristics were experimentally examined under various operating conditions. The regeneration efficiency increased from 86.2% to 98.3% during the temperature range of 358 to 403 K. The most suitable regeneration temperature for AMP was 383 K, in this experiment condition, and the regeneration efficiency of absorption/regeneration runs descended from 98.3% to 94.0%. A number of heat-stable salts （HSS） could cause a reduction in CO2 absorption capacity and regeneration efficiency. The results indicated that aqueous AMP was easier to regenerate with less loss of absorption capacity than other amines, such as, monoethanolamine （MEA）, diethanolamine （DEA）, diethylenetriamine （DETA）, and N-methyldiethanolamine （MDEA）.

关键词： carbon dioxide 2-amino-2-methyl-1-propanol regeneration efficiency energy consumption

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Tribological behaviour of oil-soluble organo-molybdenum compound as lubricating additives

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中国有色金属学会会刊:英文版 2004年第z1期14卷 386-390页

作者： shi pei-jing XU Bin-shi XU Yi QIAO Yu-lin LIU Qian National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China

A four-ball machine was employed to investigate the tribological performances and the synergetic function of organo-molybdenum compounds (molybdenum dialkyl-dithiophosphate and molybdenum dithiophosphate, coded as MoDDP and MoDTP, respectively) as additives in liquid paraffin. The morphologies of the worn surfaces and elemental distributions were observed and determined by means of scanning electron microscopy and energy dispersive spectrometry. The chemical states of some typical elements on the worn surface were analyzed on X-ray photoelectron spectroscope. The results show that MoDDP and MoDTP additives in liquid paraffin have excellent antiwear and friction-reduction properties, which are attributed to the reaction film composed of MoS2, FeS and MoO2, and the deposited film composed of phosphate on the worn surface. Moreover, these two additives have synergetic friction-reducing and antiwear effect, which is closely related to the chemical states of S on the worn surface.

关键词： oil-soluble organo-molybdenum additive friction-reduction and antiwear behaviour tribochemistry

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Performance analysis of a photovoltaic/thermal system with lunar regolith-based thermal storage for the lunar base

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Science China(Technological Sciences) 2024年第4期67卷 1113-1123页

作者： SUN WenGan ZHAO Bin pei Yu shi LingFeng HU MaoBin LI MuJun Ren Xiao pei Gang Deep Space Exploration Laboratory Hefei 230026China Department of Thermal Science and energy engineering University of Science and Technology of ChinaHefei 230026China Department of Mechanical and Aerospace engineering University of California San DiegoLa JollaCA 92093USA Department of Precision Machinery and Precision Instrumentation University of Science and Technology of ChinaHefei 230026China College of New energy China University of Petroleum(East China)Qingdao 266000China

Powering a moon base,especially keeping it warm during the long lunar night,is a big *** paper introduces a photovoltaic/thermal(PV/T)system incorporating regolith thermal storage to solve the challenge of power and heat provision for the lunar base *** vacuum of space around the moon helps this system by reducing heat *** the moon's daytime,the system not only generates electricity but also captures *** stored heat in the regolith is then used at night,reducing the amount of equipment we need to send from *** spectrally selective PV/T panels are designed to absorb a wide range of sunlight(0.3–2.5μm)while minimizing heat loss in the infrared range(3–30μm).Simulation results of the hybrid solar energy system indicate the average value of the overall efficiency is 45.9%,which relatively elevates 56.1%compared to the PV *** launch mass of the proposed PV/T system is only 8.4%of a traditional photovoltaic-lithium battery system with the same amount of energy *** the total specific energy of the proposed system is 7.3 kWh kg^(-1),while that of the photovoltaic-lithium battery system is about 0.3 kWh kg^(-1).In summary,this study proposes an alternative combined heat and electricity supply system for the lunar base,which can greatly reduce the launch mass and free up load for other scientific research equipment.

关键词： in-situ resource utilization(IRSU) regolith thermal storage photovoltaic/thermal(PV/T) spectral selectivity

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