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Communications in Theoretical Physics 2001年第11期36卷 463-468页

作者： MA dong-ping zhang Ji-ping Department of Applied Physics Sichuan University Chengdu 610065 China International Centre for Materials Physics The Chinese Academy of Sciences Shenyang 110015 China Department of Applied Physics Sichuan University Chengdu 610065 China

By taking into account all the irreducible representations and their components in the electron-phonon interaction (EPI) as well as all the levels and the admixtures of basic wavefunctions within d3 electronic configuration,the values of the parameters in the expressions of thermal shift (TS) from EPI for the ground level, R level and R line of SrTiO3:Mn4+ have been evaluated; the R-line TS and various contributions to it have been calculated in the low-temperature region. It is found that all the three terms of R-line TS from EPI relevant to the lattice vibration are red shifts. The Raman term is the largest, the neighbor-level term is the second, and the optical-branch term is very small over the range of T ≤ 80 K. The contribution to R-line TS from thermal expansion has been approximately neglected in this work. The very strong EPI relevant to its lattice vibration for SrTiO3:Mn4+ causes its R-line TS to be an unusually large red-shift. Only by taking into account the strong softening of the low-frequency acoustic modes of the lattice vibration at low temperatures, can we successfully explain the variation of R-line TS of SrTiO3:Mn4+ with temperature.

关键词： crystal fields, optical properties, electron-phonon interaction, thermal shift, softening of acoustic modes

Semiparametric theory based MIMO model and performance analysis

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The Journal of China Universities of Posts and Telecommunications 2007年第4期14卷 36-40页

作者： XU Fang-min XU Xiao-dong zhang ping Key Laboratory of Universal Wireless Communications (Beijing University ofPosts and Telecommunications) Ministry of Education Wireless TechnologyInnovation Institute Beijing 100876 China

In this article, a new approach for modeling multiinput multi-output （MIMO） systems with unknown nonlinear interference is introduced. The semiparametric theory based MIMO model is established, and Kernel estimation is applied to combat the nonlinear interference. Furthermore, we derive MIMO capacity for these systems and explore the asymptotic properties of the new channel matrix via theoretical analysis. The simulation results show that the semiparametric theory based modeling and kernel estimation are valid to combat this kind of interference.

关键词： MIMO partial linear model kernel estimation,unknown nonlinear interference

Cavity optomechanics with cold atomic gas

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Frontiers of physics 2011年第3期6卷 237-250页

作者： Ke-ye zhang Lu ZHOU Guang-jiong dong Wei-ping zhang State Key Laboratory of Precision Spectroscopy Department of Physics East China Normal University Shanghai 200062 China

We present a tutorial review on the topics related to current development in cavity optomechanics, with special emphasis on cavity optomechanical effects with ultracold gases, Bose-Einstein condensates, and spinor Bos-Einstein condensates. Topics including the quantum model and nonlinearity of the cavity optomechanics, the principles of optomechanical cooling, radiation-pressure-induced nonlinear states, the chaotic dynamics in a condensate-mirror-hybrid optomechanical setup, and the spin-mixing dynamics controlled by optical cavities are covered.

关键词： cavity optomechanics Bose-Einstein condensate spinor Bose-Einstein condensate,optical bistability

Effect of Carbon and Nitrogen Availability on Metabolism of Amino Acids in Germinating Spores of Arbuscular Mycorrhizal Fungi

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Pedosphere 2011年第4期21卷 432-442页

作者： JIN Hai-Ru JIANG dong-Hua zhang ping-Hua College of Chemistry and Life Science Zhejiang Normal University Jinhua 321004 (China)

The effects of carbon （C） and nitrogen （N） sources on N utilization and biosynthesis of amino acids were examined in the germinating spores of the arbuscular mycorrhizal （AM） fungus Glomus intraradices Schenck ＆ Smith after exposure to various N substrates, CO2, glucose, and/or root exudates. The N uptake and de novo biosynthesis of amino acids were analyzed using stable isotopic labeling with mass spectrometric detection. High-performance liquid chromatography-based analysis was used to measure amino acid levels. In the absence of exogenous N sources and in the presence of 25 mL L^-1 CO2, the germinating AM fungal spores utilized internal N storage as well as C skeletons derived from the degradation of storage lipids to biosynthesize the free amino acids, in which serine and glycine were produced predominantly. The concentrations of internal amino acids increased gradually as the germination time increased from 0 to 1 or 2 weeks. However, asparagine and glutamine declined to the low levels; both degraded to provide the biosynthesis of other amino acids with C and N donors. The availability of exogenous inorganic N （ammonium and nitrate） and organic N （urea, arginine, and glutamine） to the AM fungal spores using only CO2 for germination generated more than 5 times more internal free amino acids than those in the absence of exogenous N. A supply of exogenous nitrate to the AM fungal spores with only CO2 gave rise to more than 10 times more asparagine than that without exogenous N. In contrast, the extra supply of exogenous glucose to the AM fungal spores generated a significant enhancement in the uptake of exogenous N sources, with more than 3 times more free amino acids being produced than those supplied with only exogenous CO2. Meanwhile, arginine was the most abundant free amino acid produced and it was incorporated into the proteins of AM funsal spores to serve as an N storage compound.

关键词： biosynthesis exogenous C and N sources isotopic labeling N uptake N storage compound

Effects of AlMnCa and AlMnFe Alloys on Deoxidization of Low Carbon and Low Silicon-Aluminum Killed Steels

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Journal of Iron and Steel Research International 2008年第3期15卷 15-18页

作者： ZHAN dong-ping zhang Hui-shu JIANG Zhou-hua School of Materials and Metallurgy Northeastern University Shenyang 110004 Liaoning China

To confirm the effects of AlMnCa and AlMnFe alloys on the deoxidization and modification of Al2O3 inclusions, experiments of 4-heat low carbon and low silicon aluminum killed steels deoxidized by AlMnCa and AlMnFe alloys were done in a MoSi2 furnace at 1 873 K. It is found that the 1^# AlMnCa alloy has the best ability of deoxidization and modification of Al2O3 inclusions than 2^# AlMnCa and AlMnFe alloys. Steel A deoxidized by 1^# AlMnCa alloy has the lowest total oxygen content in the terminal steel, which is 37× 10^-6. Most of the inclusions in the steel deoxidized by 1^# AlMnCa alloy are spherical CaO-eontaining compound inclusions, and 89.1% of them are smatter than 10 μm. The diameter of the inclusion bigger than 50 μm is not found in the final steels deoxidized by AlMnCa alloys. Whereas, for the steels deoxidized by AlMnFe alloys, most inclusions in the terminal steel are Al2O3 or Al2O3-MnO inclusions, and a few of them are spherical, and only 76.8% of them are smaller than 10 μm. Some in- clusions bigger than 50μm are found in the steel D deoxidized by AlMnFe alloy.

关键词： steelmaking deoxidization inclusion AlMnCa alloy AlMnFe alloy

Selection of female parents with high fertility and high combining abilities for cross-breeding Populus tomentosa

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Journal of Forestry Research 2019年第2期30卷 445-450页

作者： Feng-ying Bai Ning Kang ping-dong zhang Xiang-yang Kang National Engineering Laboratory for Tree Breeding Beijing Advanced Innovation Center for Tree Breeding by Molecular Design Beijing Laboratory of Urban and Rural Ecological Environment Beijing Forestry University

To select maternal parents with high fertility and high combining ability during cross breeding of Populus tomentosa Carr., the ploidy level of 75 female clones was determined using flow cytometry. In addition, genetic variations and phenotypic correlations of seed traits and early growth traits, as well as the general combining ability(GCA) for seedling height(SH) and basal diameter(BD) of all diploid half-sib families were examined. A total of 26 natural triploid clones were identified. For all diploid families, family effects were significant for inflorescence length(IL), thousand kernel weight(TKW), seedling emergence rate(SER), and for SH and BD. There was a positive correlation between TKW and other traits,excluding IL. The seed-bearing coefficient(NS 9 SER)ranged from zero to 32.4%. Clones 3-10-2, 2-8, 3119,3206, and 3-10-1 had the best performance of the GCA for SH and BD. Based on the fertility and GCA for SH and BD, clone 3-10-2 and clone 3119 could be used as female parents for controlled cross-breeding of P. tomentosa.

关键词： Fertility ability General combining ability Genetic variation Half-sib family Populus tomentosa

Microstructures and properties of Al_2O_3 dispersion-strengthened copper alloys prepared through different methods

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International Journal of Minerals,Metallurgy and Materials 2016年第12期23卷 1437-1443页

作者： Zhi-qiao Yan Feng Chen Fu-xing Ye dong-ping zhang Yi-xiang Cai Guangdong Institute of Materials and Processing Guangdong Academy of Sciences State Key Laboratory of Powder Metallurgy Central South University

Al2O3 dispersion copper alloy powder was prepared by intemal oxidation, and three consolidation methods--high-velocity compaction （HVC）, hot pressing （HP）, and hot extrusion （HE）--were used to prepare Al2O3 dispersion-strengthened copper （Cu-Al2O3） alloys. The microstructures and properties of these alloys were investigated and compared. The results show that the alloys prepared by the HP and HE methods exhibited the coarsest and finest grain sizes, respectively. The alloy prepared by the HVC method exhibited the lowest relative density （98.3% vs. 99.5% for HP and 100% for HE）, which resulted in the lowest electrical conductivity （81% IACS vs. 86% IACS for HP and 87% IACS for HE）. However, this alloy also exhibited the highest hardness （77 HRB vs. 69 HRB for HP and 70 HRB for HE）, the highest compressive strength （443 MPa vs. 386 MPa for I/P and 378 MPa for HE）, and the best hardness retention among the investigated alloys. The results illustrate that the alloy prepared by the HVC method exhibits high softening temperature and good mechanical properties at high temperatures, which imply long service life when used as spot-welding electrodes.

关键词： dispersion-strengthened alloys copper alloys alumina preparation methods microstructure properties

Cross layer scheduling for real-time traffic in multiuser MIMO-OFDMA systems

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The Journal of China Universities of Posts and Telecommunications 2009年第3期16卷 24-29页

作者： SUN Qiao-yun,TIAN Hui,dong Kun,zhang ping Key Laboratory of Universal Wireless Communications,Ministry of Education,Beijing University of Posts and Telecommunications,Beijing 100876,China [a]Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

A novel cross layer scheduling algorithm is proposed for real-time （RT） traffic in multiuser downlink multiple-input multiple-output orthogonal frequency division multiple access （MIMO-OFDMA） wireless systems. The algorithm dynamically allocates resources in space, time and frequency domain based on channel state information （CSI）, users＇ quality of service （QoS） requirements and queue state information （QSI）. To provide higher data rate and spectrum efficiency, adaptive modulation and coding （AMC） is employed. The proposed algorithm can improve cell throughput and increase the number of users that can be supported while guaranteeing users＇ QoS requirements and fairness among all users. Simulation results indicate that the proposed algorithm can achieve superior performance.

关键词： MIMO-OFDMA cross layer QoS AMC

Novel resource allocation algorithms for multiuser downlink MIMO-OFDMA of FuTURE B3G systems

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Progress in Natural Science:Materials International 2009年第9期19卷 1141-1146页

作者： Qiaoyun Sun, Hui Tian *, Shuang Wang, Kun dong, ping zhang Key Laboratory of Universal Wireless Communication, Ministry of Education, Wireless Technology Innovation Institute, Beijing University of Posts & Telecommunications, Beijing 100876, China [a]Key Laboratory of Universal Wireless Communication Ministry of Education Wireless Technology Innovation Institute Beijing University of Posts & Telecommunications Beijing 100876 China

In this paper, subcarrier and power allocation problems for multiuser downlink MIMO-OFDMA of the FuTURE B3G TDD system are investigated. For the reciprocity of the TDD channel, the channel state information can be employed at the transmitter, thus eigen beamforming can be implemented efficiently. With the goal of minimizing the total transmit power under the condition that the QoS requirement of each user can be guaranteed, a novel dynamic resource allocation scheme is proposed to exploit the multiuser diversity gain. The proposed algorithm involves adaptive subcarrier allocation, adaptive modulation and eigen beamforming and achieves significant improvement in overall system performance. Based on the proposed scheme, a modified bit and power allocation is developed. The modified scheme reduces the computational complexity at little expense of system performance. Numerical simulations show that the proposed algorithm and the modified scheme can decrease the total transmit power effectively.

关键词： Adaptive modulation and coding Dynamic resource allocation Eigen beamforming MIMO–OFDMA

An Artificial Intelligence‑Assisted Flexible and Wearable Mechanoluminescent Strain Sensor System

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Nano-Micro Letters 2025年第3期17卷 217-231页

作者： Yan dong Wenzheng An Zihu Wang dongzhi zhang College of Control Science and Engineering China University of Petroleum(East China)Qingdao 266580People’s Republic of China

The complex wiring,bulky data collection devices,and difficulty in fast and on-site data interpretation significantly limit the practical application of flexible strain sensors as wearable *** tackle these challenges,this work develops an artificial intelligenceassisted,wireless,flexible,and wearable mechanoluminescent strain sensor system(AIFWMLS)by integration of deep learning neural network-based color data processing system(CDPS)with a sandwich-structured flexible mechanoluminescent sensor(SFLC)*** SFLC film shows remarkable and robust mechanoluminescent performance with a simple structure for easy *** CDPS system can rapidly and accurately extract and interpret the color of the SFLC film to strain values with auto-correction of errors caused by the varying color temperature,which significantly improves the accuracy of the predicted strain.A smart glove mechanoluminescent sensor system demonstrates the great potential of the AIFWMLS system in human gesture ***,the versatile SFLC film can also serve as a encryption *** integration of deep learning neural network-based artificial intelligence and SFLC film provides a promising strategy to break the“color to strain value”bottleneck that hinders the practical application of flexible colorimetric strain sensors,which could promote the development of wearable and flexible strain sensors from laboratory research to consumer markets.

关键词： Mechanoluminescent Strain sensor Flexible Deep learning Wireless