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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

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

Tomato Root Response to Subsurface Drip Irrigation

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Pedosphere 2004年第2期14卷 205-212页

作者： ZHUGEYu-ping zhangXu-dong zhangYu-Long LIJun YANGLi-Juan HUANGYi LIUMing-Da KeyLaboratoryofTerrestrialEcologicalProcess InstituteofAppliedEcologyChineseAcademyofSciencesShenyang110016（China）.E-mail：zgyp@*** LandandEnvironmentalCollege ShenyangAgriculturalUniversityShenyang110161（China）

Four depth treatments of subsurface drip irrigation pipes were designated as 1) at 20,2) 30 and 3) 40 cm depths all with a drip-proof flumes underneath,and 4) at 30 cm without a drip-proof flume to investigate the responses of a tomato root system to different technical parameters of subsurface drip irrigation in a glass greenhouse,to evaluate tomato growth as affected by subsurface drip irrigation,and to develop an integrated subsurface drip irrigation method for optimal tomato yield and water use in a glass greenhouse. Tomato seedlings were planted above the subsurface drip irrigation pipe. Most of the tomato roots in treatment 1 were found in the top 0-20 cm soil depth with weak root activity but with yield and water use efficiency (WUE) significantly less (P ---- 0.05) than treatment 2; root activity and tomato yield were significantly higher (P = 0.05) with treatment 3 compared to treatment 1; and with treatment 2 the tomato roots and shoots grew harmoniously with root activity,nutrient uptake,tomato yield and WUE significantly higher (P= 0.05) or as high as the other treatments. These findings suggested that subsurface drip irrigation with pipes at 30 cm depth with a drip-proof flume placed underneath was best for tomato production in greenhouses. In addition,the irrigation interval should be about 7-8 days and the irrigation rate should be set to 225 m3 ha-1 per event.

关键词： greenhouse root system response soil water subsurface drip irrigation

STUDY ON A NEW APPROACH OF CAVITATION EROSION TEST FOR NONMETALLIC MATERIALS

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Journal of Hydrodynamics 1999年第3期11卷 75-82页

作者： Liu Zhi ping, zhang dong, Jin Tai lai China Institute of Water Resources and Hydropower Reserarch, Beijing 100038, P.R.China (Received Nov.9, 1998)

This paper deals with the reconstruction and innovation of an ordinary magnetostriction apparatus for cavitation erosion tests of non metallic materials. It aims at making testing specimen to be independent of amplitude amplifier rod, thus overcoming the difficulties of fixing tightly the non metallic specimen to the vibrating rod. Such approach makes the exposure area greatly increased and effectively mitigates the effect of non homogeneity of non metallic specimen on the testing results, thus extending the application of magnetostriction apparatus to carry out cavitation erosion tests to larger size of non metallic and non homogeneous materials. It will render a set of new innovative apparatus and recently developed method to conduct fast and simple cavitation erosion test in days to come. Simultaneously, several tests on non metallic materials have been made by means of such new apparatus, yielding satisfactory results and witnessing the availability of new methods.

关键词： cavitation erosion non metallic materials magnetostriction

Molecular dynamics simulations of helium transport through inorganic mineral nanopores

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Science China Earth Sciences 2025年第1期68卷 237-252页

作者： Dandan SONG ping GUAN Chi zhang Jiahao REN School of Earth and Space Sciences Peking University

Helium transport through nanoscale inorganic mineral pores and pore throats is essential for its overall migration. To elucidate helium's transport dynamics within nanopores, we employed equilibrium and non-equilibrium molecular dynamics simulations to investigate helium's static self-diffusion and pressure-driven flow in quartz slit-shaped nanopores. We also introduced water and various gases, including hydrogen, methane, ethane, nitrogen, and carbon dioxide, into the nanopores to assess their influence on helium transport. Our findings indicate minimal helium adsorption on quartz pore surfaces. Under conditions where the pore size is less than 5 nm and the pressure under 10 MPa, environmental factors markedly influence helium diffusion. Large pore sizes, high temperatures, and low gas pressures enhance helium desorption and facilitate faster diffusion. We observed a positive correlation between helium flow velocity and factors such as pore size, pressure gradient, and surface smoothness of the pores. Notably, the presence of pore water and carrier gases in quartz nanopores, which diffuse more slowly than helium, tends to reduce helium surface adsorption and slow its diffusion. Among the carrier gases studied, nitrogen showed similar adsorption capacity, diffusivity, and stability to helium, while carbon dioxide displayed the highest adsorption capacity and the slowest diffusion rate, markedly differing from helium. Based on the simulation results, we concluded that water and carrier gases primarily function as transport mediums in helium migration, moving together with helium. Nitrogen, which shares similar properties with helium, effectively assists in this co-migration process. Conversely, carbon dioxide, due to its high adsorption capacity and slow diffusion, tends to be lost during co-migration. As a result, gas reservoirs with high nitrogen levels and low carbon dioxide levels are more likely to have higher helium concentrations. Additionally, the smaller por

关键词： Helium transport Slit nanopores Molecular dynamics simulations Diffusion Flow carriers

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 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

HNRNPC as a pan-cancer biomarker and therapeutic target involved in tumor progression and immune regulation

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Oncology Research 2025年第1期33卷 83-102页

作者： YUEZHOU zhang ZHAO zhang JINXIN dong CHANGAN LIU Department of Hepatobiliary Surgery The Second Affiliated Hospital of Chongqing Medical UniversityChongqing400016China Department of Hepatobiliary Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing400016China

Background:Aberrant expression of RNA-binding proteins(RBPs)has been linked to a variety of diseases,including hematological disorders,cardiovascular diseases,and multiple types of *** nuclear ribonucleoprotein C(HNRNPC),a member belonging to the heterogeneous nuclear ribonucleoprotein(hnRNP)family,plays a pivotal role in nucleic acid *** studies have underscored the significance of HNRNPC in tumorigenesis;however,its specific role in malignant tumor progression remains inadequately ***:We leveraged publicly available databases,including The Cancer Genome Atlas(TCGA),to explore the potential involvement of HNRNPC across various ***,we performed experimental validation studies focused on liver ***:Our analysis revealed that HNRNPC is overexpressed in a wide range of common malignancies,including liver and lung cancers,and is strongly linked to unfavorable ***,HNRNPC was observed to be closely linked to tumor *** immune checkpoint analysis and immune cell infiltration assessment,HNRNPC emerged as a potential target for modulating tumor ***,silencing of HNRNPC markedly inhibited the proliferation,metastasis,and infiltration of liver cancer ***:In summary,our findings highlight HNRNPC as a prognostic marker in various cancers,including liver cancer,and suggest its involvement in shaping the tumor immune *** insights offer potential avenues for improving clinical outcomes in tumors with elevated HNRNPC expression,particularly through immunotherapeutic strategies.

关键词： Heterogeneous nuclear ribonucleoprotein C(HNRNPC) Pan-cancer analysis Tumor immunity Prognostic biomarker Immunotherapeutic target Hepatocellular carcinoma