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Performance analyses of OFDM AF relaying system in the presence of phase noise with APS and IPS

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The Journal of China Universities of Posts and Telecommunications 2016年第5期23卷 1-9页

作者： Huang Jing Li Juhu zhang haiyan School of Information Beijing Forestry University

This article investigates the significant performances of orthogonal frequency division multiplexing （OFDM）-based dual-hop system in the presence of phase noise （PN）. A scenario with Rayleigh fading statistics on both hops is assumed. Amplification factor for this amplify-and-forward （AF） relay networks system is divided into two conditions, average power scaling （APS） and instantaneous power scaling （IPS）. Before deriving signal-to-noise ratios （SNR） under APS and IPS, the Gaussianity of intercarrier interference （ICI） is proved firstly. The accurate closed-form expressions of end-to-end SNR cumulative distribution functions （CDF） and probability density functions （PDF） for both cases are obtained later. With the help of moment generating functions （MGF）, we have closed-form asymptotic expressions of bit error rate （BER）, which show that the BER of system in the presence of PN cannot exceed a fixed level even when SNR in high regime. Finally, simulations verify accuracy of the results. Conclusion analysis will provide a useful help in future application of the system.

关键词： OFDM-AF system phase noise average power scaling instantaneous power scaling

ERF1 delays flowering through direct inhibition of FLOWERING LOCUS T expression in Arabidopsis

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Journal of Integrative Plant Biology 2021年第10期63卷 1712-1723页

作者： Yanli Chen Liping zhang haiyan zhang Ligang Chen Diqiu Yu CAS Key Laboratory of Tropical Plant Resources and Sustainable Use Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Center of Economic Botany Core Botanical GardensChinese Academy of SciencesMenglunMengla 666303China State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan Yunnan UniversityKunming 650091China

ETHYLENE RESPONSE FACTOR1(ERF1)is a key component in ethylene signaling,playing crucial roles in both biotic and abiotic stress ***,we demonstrate that ERF1 also has an important role during floral initiation in Arabidopsis *** or knockout of ERF1 accelerated floral initiation,whereas overexpression of ERF1 dramatically delayed floral *** contrasting phenotypes were correlated with opposite transcript levels of FLOWERING LOCUS T(FT).Chromatin immunoprecipitation(ChIP)assays revealed that ERF1 associates with genomic regions of the FT gene to repress its ***-10/ERF1RNAi plants showed a similar flowering phenotype to the ft-10 mutant,whereas the flowering of FTox/ERF1ox mimicked that of FTox plants,suggesting that ERF1 acts upstream of FT during floral ***,altered floral transition in ethylene-related mutants was also correlated with FT *** analysis suggested that ERF1 also participates in delay in flowering-time control mediated by the ethylene precursor 1-aminocyclopropane-1-carboxylic ***,ERF1 may act as a negative modulator of flowering-time control by repressing FT transcription in Arabidopsis.

关键词： Arabidopsis thaliana ethylene ETHYLENE RESPONSE FACTOR1 floral initiation FLOWERING LOCUS T

Spatial diff erence in net growth rate of Yesso scallop Patinopecten yessoensis revealed by an aquaculture ecosystem model

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Journal of Oceanology and Limnology 2022年第1期40卷 373-387页

作者： Xueliang NAN Hao WEI haiyan zhang Hongtao NIE School of Marine Science and Technology Tianjin UniversityTianjin 300072China

Identifying the main factors on spatial diff erences in net growth rate of Yesso scallop(Patinopecten yessoensis)in culture system is the key to eff ective aquaculture management and *** a 3D ecosystem model(ROMS-CoSiNE)with a dynamic energy budget model for scallops,a Yesso scallop culture ecosystem(YeSCE)model was established with which scallop growth was simulated with real seeding density and juvenile size from local aquaculture experiments from December 1,2012 to November 30,*** show that the YeSCE model has reasonably simulated the environmental variation and scallop net growth rate in the Changhai sea *** growth of scallops was slow in winter and midsummer and was limited mainly by *** availability was a key factor that contributed to the fast growth of the scallops during spring to early summer and in ***,the scallops cultured in the north part of the Changhai sea area grew faster than those in the south;and the net growth rate for scallops cultured near the island was signifi cantly higher compare to the others,which is probably correlated to the spatial distribution of food *** on the correlation analysis,the spatial diff erences of the net growth rate were largely aff ected by the length of the match timing of temperatures and food *** results of this study provide a scientifi c support for optimizing bottom culture planning and adjusting bottom culture methods.

关键词： 3D ecosystem model shellfi sh aquaculture Yesso scallop Patinopecten yessoensis net growth rate Changhai sea area

Bimetal MOF-derived NiFe-P nanocomposites coupled with Cu_(3)P nanoparticles to construct tandem electron transfer channels for photocatalytic hydrogen evolution

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Journal of Environmental Sciences 2024年第3期137卷 333-346页

作者： haiyan zhang Shitao Yang Peng Zhu Senpei Tang Ming Li College of Chemistry and Chemical Engineering Jishou UniversityJishou 416000China School of Account Hunan University of Technology and BusinessChangsha 410205China

Finely modulated light-induced charge separation and transfer is a central challenge to achieve efficient *** progress has been made in this field,most of the previous research works focused on the separation or migration of photogenerated carriers but did not build a bridge between the *** to realize the strong driving and precise migration of carriers has become the focus of our *** report an ingeniously designed ternary *** NiFe-MOF as the“parent material”,the FeP_(4)/Ni_(x)P_(y)heterojunction is derived in situ while maintaining the frame structure through gas-solid reaction,and finally the Z-type electron transfer is *** Cu_(3)P anchoring spindle matrix,an electron transport tunnel is opened up in Cu_(3)P/FeP_(4)/Ni_(x)P_(y)ternary heterojunction under the action of p-n heterojunction built-in electric field driving and accurate energy band *** strong driving force of the built-in electric field provides an inexhaustible power for the transmission of electrons,and the fine series of electron transmission channels realizes the precise transmission of *** above fine design makes the perfect fit between the built-in electric field and the electron transfer channel,which not only effectively improves the embarrassing situation of insufficient electron driving force of hydrogen evolution reaction in the previous research,but also makes up for the weakening of semi-conductor reduction ability caused by the construction of traditional p-n *** research work provides a new idea for the construction of multiple heterostructures and the design of fine interface engineering in the future.

关键词： Cu_(3)P/FeP_(4)/Ni_(x)P Built-in electric field Electron transfer channels Photocatalysis

Migration of sulfur in in-situ gasification chemical looping combustion of Beisu coal with iron-and copper-based oxygen carriers

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Chinese Journal of Chemical Engineering 2021年第7期34卷 247-255页

作者： Ming Luo Lunzheng Zhou Jianjun Cai haiyan zhang Chao Wang School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013China State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021China School of Environmental Science and Engineering and Key Laboratory of Municipal Solid Southern University of Science and TechnologyShenzhen 518055China

Chemical looping combustion(CLC)is an energy conversion technology with high efficiency and inherent separation of CO_(2).The existence of sulfur in coal may affect the CO_(2) purity and the performance of oxygen carrier due to the interactions between sulfur contaminants and oxygen *** migration of sulfur in Beisu coal during the in-situ gasification chemical looping combustion(i G-CLC)process using two oxygen carriers(iron ore and Cu O/Si O_(2))was investigated *** thermodynamic analysis results showed the formation of metal sulfides was thermodynamically favored at low temperatures and low oxygen excess coefficients,while they were obviously inhibited and the production of SO_(2) was significantly promoted with an increase in temperature and oxygen excess ***,part of sulfur was captured and fixed in the forms of alkali/alkaline earth metal sulfate due to the high amount of alkali/alkaline earth metal oxides in the coal ash or/and oxygen *** experimental results showed that the sulfur in coal mainly released in the form of SO_(2),and the sulfur conversion efficiency(XS)in the reduction stage were 51.04%and 48.24%when using iron ore and Cu O/Si O_(2) *** existence of metal sulfides was observed in the reduced oxygen *** values of XSin the reoxidation process reached 3.80%and 7.64%when using iron ore and Cu O/Si O_(2) *** residue and accumulation of sulfur were also found on the surfaces of two oxygen carriers.

关键词： SO_(2) Coal Iron ore Copper-based Chemical looping combustion

Electroluminescence efficiency in bilayer organic light-emitting devices with LiF/Al cathode

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Science China(Physics,Mechanics & Astronomy) 2007年第1期50卷 31-40页

作者： LI HongJian ZHU RuHui YAN LingLing zhang haiyan School of Physics Science and Technology Central South UniversityChangsha 410083China

An analytical model to calculate electroluminescence (EL) efficiency of bilayer organic light-emitting devices, considering the influence of introducing LiF insulating buffer layer at metal/organic interface on the barrier height for electron injection, was presented. The relations of EL efficiency versus the applied voltage and injection barrier or internal interfacial barrier or the thickness of organic layer were discussed. The results indicate that: (1) when δ e/δ h 2, M/O becomes contact limited; and when δ e/δ h = 2 (Θ h ～ 0.2 eV, Θ ～ 0.3 eV), there is a transition from ohmic contact to contact limited; (2) η EL decreases with the increase of δ′ e/δ′ h; however, when δ′ e/δ′ h > 2.5 (H′ h ～ 0.2 eV, H′ e～ 0.4 eV), the changes of η EL are very small, which shows that η EL is dominated by the carrier’s injection; (3) when increasing L h/L, η R has a descending trend at low voltage and a rising one at higher voltage. For a given L h/L, η EL first increases and then decreases with the increasing applied voltage, and as L h/L further increases, the variation tendency of η EL is more obvious. These conclusions are in agreement with the reported theoretic and experimental results.

关键词： electroluminescence efficiency injection barrier interfacial barriers LiF modification

Vegetation-environment Relationships Between Northern Slope of Karlik Mountain and Naomaohu Basin,East Tianshan Mountains

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Chinese Geographical Science 2012年第3期22卷 288-301页

作者： zhang haiyan QIAN Yibing WU Zhaoning WANG Zhongchen Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China College of Geology and Exploration Engineering Xinjiang University Urumqi 830046 China Environmental Development Center of Ministry of Environmental Protection Beijing 100029 China

Based on data from 22 sample plots and applying the Canonical Correspondence Analysis （CCA）, this paper discusses the vegetation-environment relationships between the northern slope of Karlik Mountain and Naomaohu Ba- sin, which is situated in the easternmost end of the Tianshan Mountains, Xinjiang Uygur Autonomous Region, China. For the zonal vegetation, community diversity of mountain vegetation is higher than that of the desert vegetation due to environmental factors. The CCA ordination diagram revealed that the composition and distribution of vegetation types are mainly determined by altitude, soil pH and soil salt content. With increasing elevation, the soil pH and total salt content decrease but the contents of soil organic matter, soil water, total nitrogen and total phosphorus increase gradu- ally. In the CCA ordination diagrams, the sample plots and main species can be divided into five types according to their adaptations to the environmental factors. Type Ⅰ is composed of desert vegetation distributed on the low moun- tains, hills, plains and deserts below an elevation of 1900 m; type Ⅱ is distributed in the mountain and desert ecotone with an elevation of 1900-2300 m, and includes steppe desert, desert steppe and wetland meadow; type Ⅲ is very sim- ply composed of only salinized meadow; type Ⅳ is distributed above an elevation of 2300 m, containing mountain steppe, meadow steppe, subalpine meadow and alpine meadow; type Ⅴ only contains salinized meadow. The results show that with increasing elevation, species combination changes from the xerophytic shrubs, semi-shrubs and herbs distributed in the low altitude zone with arid climate to the cold-tolerant perennial herbs growing in the high altitudinal zone with cold climate.

关键词： vegetation pattern environmental factors canonical correspondence analysis (CCA) vegetation-environment relationships Tianshan Mountains Xinjiang

Combined transplantation of bone marrow mesenchymal stem cells and pedicled greater omentum promotes locomotor function and regeneration of axons after spinal cord injury in rats

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Neural Regeneration Research 2008年第4期3卷 358-362页

作者： Liang Li Zhiying zhang haiyan Lin Congli Ren Chuansen zhang Department of Anatomy the Secondary Military Medical University of Chinese PLA Shanghai 200433 China

BACKGROUND： According to previous studies, the neuroprotective effect of the pedicled greater omentum may be attributed to the secretion of neurotrophic factors and stimulation of angiogenesis. The neurotrophic factors released from the pedicled greater omentum, such as brain-derived neurotrophic factor and neurotrophin 3/4/5 could exert a neuroprotective effect on the damaged host neural and glial cells, and also could induce the transdifferentiation of transplanted bone marrow mesenchymal stem cells （BMSCs） into neural cells. OBJECTIVE： Based on the functions of the omentum of neuro-protection and vascularization, we hypothesize that the transplantation of BMSCs and pedicled greater omentum into injured rat spinal cord might improve the survival rate and neural differentiation of transplanted BMSCs and consequently gain a better functional outcome. DESIGN, TIME AND SETFING： A randomized, controlled animal experiment. The experiments were carried out at the Department of Anatomy, the Secondary Military Medical University of Chinese PLA between June 2005 and June 2007. MATERIALS： Fifteen male inbred Wistar rats, weighing （200±20） g, provided by the Experimental Animal Center of the Secondary Military Medical University of Chinese PLA were used and met the animal ethical standards. Mouse anti-BrdU and mouse anti-NF200 monoclonal antibody were purchased from Boster, China. METHODS： Cell culture： We used inbred Sprague-Dawley rats to harvest bone marrow for culture of BMSCs and transplantation to avoid possible immune rejection. BMSCs were cultured via total bone marrow adherence. Experimental grouping and intervention： The rats were randomly divided into a control group, cell group and combined group, five rats per group. Rats in the control group underwent spinal cord injury （SCI） only, during which an artery clamp with pressure force of 30 g was employed to compress the spinal cord at the Tl0 level for 30 seconds to produce the SCI model. 5 μ L PBS containing 10^5 B

关键词： spinal cord injuries transplantation mesenchymal stem cell omentum nerve regeneration

Role of neuregulin-1 in peripheral nerve injury

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Neural Regeneration Research 2010年第14期5卷 1104-1108页

作者： Zhengdong Kong Zhiying zhang haiyan Lin Chuansen zhang Department of Anatomy Second Military Medical University of Chinese PLA Shanghai 200433 China

Peripheral nerve injury in humans often leads to permanent functional deficits. Schwann cells play an important role in the recovery of peripheral nerve injury by ensheathing axons and providing various neurotrophic factors. Neuregulin-1 （NRG-1） provides axonal signals, which allow dedifferentiation and rapid proliferation of Schwann cells. Subsequently, NRG-1 promotes axonal myelination and influences myelin thickness. Moreover, NRG-1 plays a critical role in synapse formation in the neuromuscular junction. These effects, together, suggest that NRG-1 promotes recovery of peripheral nerve injury.

关键词： neuregulin-1 nerve injury neurotrophic factors neuroregeneration peripheral nerve Schwann cells myelination review