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Chinese Journal of Chemical Engineering 2021年第6期34卷 217-227页

作者： Liang Chun Guangcai Gong xi fang Pei Peng Key Laboratory of Building Safety and Energy Efficiency Ministry of Education College of Civil Engineering Hunan UniversityChangsha 410082China

Temperature and humidity independent control(THIC)air-conditioning system is a promising *** this work,a novel temperature and humidity independent control(THIC)system is proposed,namely VMD-ACERS,which integrates vacuum membrane-based dehumidification and air carrying energy radiant air-conditioning *** work establishes a novel coefficient of performance(COP)model of *** main parameters affecting the COP of conventional fan coil unit cooling system(FCUCS)and VMD-ACERS are *** performance of FCUCS and VMD-ACERS are compared,and the energy-saving potential of VMD-ACERS is *** indicate that,for FCUCS,the importance ranking of parameters is basically ***,for VMD-ACERS,the importance ranking will be affected by FCU and *** most important parameters of VMD-ACERS are condensation temperature and permeate side *** the contrary,superheating,subcooling are relatively less important *** VMD-ACERS,it is not necessary to pursue the membrane with very high selectivity,because the selectivity of membrane would also be a less important parameter when it reaches *** COP of VMD-ACERS is higher than that of FCUCS when the permeate side pressure is higher than 8 k *** VMD-ACERS solves two technical problems about power-saving and thermal comfort of conventional THIC,and can extend the application of THIC air-conditioning system.

关键词： Fan coil unit cooling system Temperature and humidity independent control ACERS Vacuum membrane-based dehumidification COP

Analytical Solution for an Ultracold Trapped Ion at the Node of the Standing Wave Laser Without Rotating Wave Approximation

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Communications in Theoretical Physics 2001年第11期36卷 597-600页

作者： fang xi-Ming FENG Mang Department of Physics Hunan Normal UniversityChangsha 410081China Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsWuhan Institute of PhysicsAcademia SinicaWuhan 430071China

A method of solving an ultracold trapped ion at the node of the standing wave laser without rotating wave approximation is proposed and the analytical forms of the eigenfunctions and eigenenergies of the system are pr... 详细信息

关键词： ultracold trapped ion,analytical solution,rotating wave approximation

Surface-exchange of NOx and NH_3 above a winter wheat field in the Yangtze Delta, China

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Journal of Environmental Sciences 2006年第4期18卷 689-700页

作者： fang Shuang-xi ZHANG Yi MU Yu-jing Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

A four-dynamic-chamber system was constructed to measure NOx and NH3 surface-exchange between a typical wheat field and the atmosphere in the Yangtze Delta, China. The average fluxes of NO, NO2 and NH3 were 79, -5.6 and -5.1 ngN/（m^2·s）, and 91, -1.8 and 23 ngN/（m^2·s）, respectively for the wheat field and the bare soil. The NO flux was positively correlated with soil temperature and the fluxes of NO2 and NH3 were negatively correlated with their ambient concentrations during the investigated period. The compensation point of NO2 between the wheat field and the atmosphere was 11.9 μg/m3. The emissions of NO-N and NH3-N from the urea applied to the wheat field were 2.3% and 0.2%, respectively, which indicated that the main pathway of N loss from the investigated winter wheat field was NO. Application of a mixture of urea and lignin increased the emissions of NO, but also greatly increased the yield of the winter wheat.

关键词： NOx NH3, flux surface-exchange

Quantum Phase Transitions in Spin Star Configuration

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Communications in Theoretical Physics 2008年第5期49卷 1353-1356页

作者： DENG Hong-Liang fang xi-Ming Key Laboratory of Quantum Structure and Quantum Control of Ministry of Education and Department of Physics Hunan Normal University Changsha 410081 China

We consider a generalized spin star configuration that can be solved exactly, with the central spin-1/2 system embedded in an outer ring of N spin-1/2 particles （denoted as spin bath）. In this model, we consider a modified version of the spin star model, by taking into account, besides the interaction of the central spin with the bath, the interactions between the spins of the bath as well. The general expressions of the eigenstates as well as the eigenvalues of the model are derived with the use of the symmetries of system. We then investigate the properties of the ground quantum phase transitions in some limiting cases in the model and show that the occurrence of quantum phase transitions and the desired ground states can be obtained by varying the external control parameters.

关键词： quantum phase transitions ground state

Design of coordinator to eliminate redundant local retransmission in wireless networks

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 63-69页

作者： fang xi WANG Jun WANG Yong JIANG Feng Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China

Owing to limited bandwidth, high bit error rate, and bursty error in the wireless environment, the performance of the transmission control protocol （TCP） degrades greatly in wireless networks. Up to now, many researchers have contributed greatly to the wireless TCP field. However, in most of their works, the wireless TCP module usually works in the TCP layer and has no idea of the actual time of the packet transmission, which is determined by the Scheduler in the media access control （MAC） layer, and this will bring the inaccuracy to the local retransmission fimeout and induce the redundant local retransmission. In this article, a coordinator is introduced into the base-station （BS）, which can provide efficient cooperation between the TCP module and the scheduler module. On the bais of the performance analysis and simulation results, the proposed method is shown to eliminate redundant local retransmission, increase throughput, and improve TCP-level fairness in wireless networks. Moreover, this scheme is orthogonal to those existing wireless TCP schemes, thus it can give great compatibility to the current networks, and further enhance the performance of TCP under the condition that the performance improvement benefiting from the existing approaches will not be affected.

关键词： TCP wireless network coordinator scheduling throughput fairness

Annealing Effects on Properties of Bi—Substituted Garnet Films with Perpendicular Anisotropy Prepared by a Sol—Gel Method

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Chinese Physics Letters 2003年第5期20卷 746-748页

作者： ZHANGYue-Pin WANGxian-Ying RuanHao SHENDe-fang GANFu-xi ShanghaiInstituteofOpticsandFineMechanics ChineseAcademyofSciencesShanghai201800

Bi-substituted garnet films with perpendicular anisotropy have been prepared by a sol-gel method. Annealing effects on magneto-optical properties and structures of the films are studied. The results indicate that the Kerr hysteresis loops of garnet films have good squareness at annealing temperatures above 650°C, the coercive force Hc of these films increases from 1070 to 1570 Oe with the increasing temperature from 650°C to 700°C. The Kerr rotation of the films was changed with the increasing annealing temperature, and there is a maximum value (0.82°) at 675°C. It was found that the structure of the films is a single phase of garnet without preferring orientation when the annealing temperature is about 650°C, but a new phase (Bi2Al4O9) can be formed when the annealing temperature reaches 675°C, another new phase (Bi2Fe4O9) appears when the annealing temperature is about 700°C.

关键词：石榴石薄膜正交各向异性溶胶-凝胶法磁光效应结构分析退火薄膜生长

Exact Treatment for Two Ultracold Ions in a Two-Dimensional Penning Trap

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Chinese Physics Letters 1998年第4期15卷 258-259页

作者： FENG Mang fang xi-ming SHI Lei YAN Min ZHU xi-wen Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071

The Schrödinger equation of two ultracold ions confined in xy plane of the Penning trap is exactly solved and the analytical form of the wave function of the system is obtained.A numerical calculation for a continued ... 详细信息

关键词： number Penning continued

Teleportation of Two Quantum States via the Quantum Computation

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Chinese Physics Letters 2000年第3期17卷 168-170页

作者： FENG Mang ZHU xi-Wen fang xi-Ming YAN Min SHI Lei Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071

A scheme of teleportation of two unknown quantum states via quantum computation is *** comparison with the former proposals shows that our scheme is more in tune with the original teleportation proposal and the effici... 详细信息

关键词： quantum scheme Quantum

Soil-plant co-stimulation during forest vegetation restoration in a subtropical area of southern China

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Forest Ecosystems 2020年第3期7卷 404-420页

作者： Chan Chen xi fang Wenhua xiang Pifeng Lei Shuai Ouyang and Yakov Kuzyakov Faculty of Life Science and Technology Central South University of Forestry and TechnologyChangsha410004China Huitong National Field Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystem in Hunan Province Huitong438107China Department of Soil Science of Temperate Ecosystems Georg-August University of Gottingen37077GöttingenGermany Department of Agricultural Soil Science Georg-August University of Gottingen37077GöttingenGermany

Background: Soil and vegetation have a direct impact on the process and direction of plant community succession, and determine the structure, function, and productivity of ecosystems. However, little is known about the synergistic influence of soil physicochemical properties and vegetation features on vegetation restoration. The aim of this study was to investigate the co-evolution of soil physicochemical properties and vegetation features in the process of vegetation restoration, and to distinguish the primary and secondary relationships between soil and vegetation in their collaborative effects on promoting vegetation restoration in a subtropical area of ***: Soil samples were collected to 40 cm in four distinct plant communities along a restoration gradient from herb(4–5 years), to shrub(11–12 years), to Pinus massoniana coniferous and broadleaved mixed forest(45–46 years), and to evergreen broadleaved forest(old growth forest). Measurements were taken of the soil physicochemical properties and Shannon–Wiener index(SD), diameter at breast height(DBH), height(H), and biomass. Principal component analysis, linear function analysis, and variation partitioning analysis were then performed to prioritize the relative importance of the leading factors affecting vegetation ***: Soil physicochemical properties and vegetation features showed a significant trend of improvement across the vegetation restoration gradient, reflected mainly in the high response rates of soil organic carbon(SOC)(140.76%), total nitrogen(TN)(222.48%), total phosphorus(TP)(59.54%), alkaline hydrolysis nitrogen(AN)(544.65%),available phosphorus(AP)(53.28%), species diversity(86.3%), biomass(2906.52%), DBH(128.11%), and H(596.97%).The soil properties(pH, SOC, TN, AN, and TP) and vegetation features(biomass, DBH, and H) had a clear coevolutionary relationship over the course of restoration. The synergistic interaction between soil properties and vegetation features had the g

关键词： Vegetation restoration Soil physicochemical properties Soil organic carbon Vegetation features Driving factors

Heteropolytungstates Containing Organotin and Cobalt or Zinc Atom

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Chemical Research in Chinese Universities 1999年第4期15卷 317-321页

作者： WANG xiao-hong fang xi-kui LIU Jing-fu Department of Chemistry Northeast Normal UniversityChangchun 130024P.R.China

Organotin substituted heteropolytungstates with cobalt or zinc atom as the central atom, \{K 6H[XW 11 O 39 (RSn)]\}· n H 2O(X=Zn, Co; R=CH 3OOCCH 2CH 2, CH 2OOCCH(CH 3)CH 2, NCCH 2CH 2) were prepared and characterized by elemental analysis, IR, UV Vis spectroscopy, ESR, NMR spectroscopy and electrochemical study. The results show that these anions possess Keggin like structures.

关键词： Organotin Transition metal Heteropolyanion