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Chinese Physics Letters 2019年第11期36卷 22-26页

作者： qiu-run he Jing Guo Bao-Fu Zhang Zhong-Xing Jiao School of Physics Sun Yat-sen UniversityGuangzhou 510275 Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082 National Demonstration Center for Experimental Physics Education Sun Yat-sen UniversityGuangzhou 510275

We develop a two-stage end-pumped Nd:YVO4 amplifier seeded by a passively Q-switched microchip laser. An average output power of 13.5 W with repetition rate up to 7 kHz and pulse duration of ~1.24 ns is obtained,corresponding to a pump extraction efficiency of 16.1%(19.5% for the second stage) and peak power of ~1.5 *** beam quality factors at maximum output power are measured to be Mx2= 1.56 and My2= 1.48. We introduce an analytical model to estimate gain and beam quality after amplification. This model focuses on the influence of ratio of seed spot radius to pump spot radius when designing an amplifier. Moreover, our experiments reveal that the re-imaging system in the double-pass configuration can be used to enhance the beam quality.

关键词： Nd:YVO4 amplifier pump

影响MIMO系统信道容量性能的主要因素研究

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电子科技大学学报 2008年第1期37卷 50-53页

作者：陈欣捷仇润鹤东华大学信息科学与技术学院上海松江区200051

为了研究多天线系统的信道容量特性,从信息论角度对使用多个发射和接收天线的多输入多输出(MIMO)系统的信道容量进行了理论推导,通过建立MIMO系统模型,分析了频率选择性衰落信道下的MIMO系统信道容量,重点探讨了信道相关性、天线距离以... 详细信息

为了研究多天线系统的信道容量特性,从信息论角度对使用多个发射和接收天线的多输入多输出(MIMO)系统的信道容量进行了理论推导,通过建立MIMO系统模型,分析了频率选择性衰落信道下的MIMO系统信道容量,重点探讨了信道相关性、天线距离以及RicianK-因子等因素对MIMO系统容量的影响,运用信息论理论对其进行了量化的分析,并通过计算机仿真进一步验证了结论。

关键词：信道容量相关性多输入多输出 Rician K-因子

Porous TiFe_(2) intermetallic compound fabricated via elemental powder reactive synthesis

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 764-772页

作者： Qian Zhao Zhenli he Yuehui he Yue qiu Zhonghe Wang Yao Jiang State Key Laboratory of Powder Metallurgy Powder Metallurgy Research InstituteCentral South UniversityChangsha 410083China

Porous intermetallics show potential in the field of filtration and separation as well as in the field of ***,porous Ti Fe2intermetallics were fabricated by the reactive synthesis of elemental *** phase transformation and pore formation of porous TiFe2intermetallics were investigated,and its corrosion behavior and hydrogen evolution reaction(heR)performance in alkali solution were *** TiFe2intermetallics with porosity in the range of 34.4%-56.4%were synthesized by the diffusion reaction of Ti and Fe elements,and the pore formation of porous TiFe2intermetallic compound is the result of a combination of the bridging effect and the Kirkendall *** porous TiFe2samples exhibit better corrosion resistance compared with porous 316L stainless steel,which is related to the formation of uniform nanosheets on the surface that hinder further corrosion,and porous TiFe2electrode shows the overpotential of 220.6 and 295.6 mV at 10 and 100 mA·cm-2,suggesting a good catalytic *** synthesized porous Fe-based intermetallic has a controllable pore structure as well as excellent corrosion resistance,showing its potential in the field of filtration and separation.

关键词： TiFe2 intermetallic compound porous materials reactive synthesis corrosion behavior hydrogen evolution reaction

Histological,transcriptomic,and gene functional analyses reveal the regulatory events underlying gibberellin-induced parthenocarpy in tomato

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Horticultural Plant Journal 2024年第1期10卷 156-170页

作者： Shaobo Niu Yu he Siwei Yan Zhengliang Sun run Cai Yan Zhang Shaanxi Engineering Research Center for Vegetables College of HorticultureNorthwest A&F UniversityYanglingShaanxi 712100China

Gibberellin(GA)is one of the major plant hormones that promote parthenocarpy,a highly valuable agronomic ***,we demonstrated that exogenous GA3application triggered the formation of parthenocarpic fruits with smaller size but unchanged shape in tomato(Solanum lycopersicum).These fruits exhibited a thicker pericarp,undeveloped ovules,and few jelly tissues,leading to smaller locules with empty *** investigation showed that GA treatment produced more cell layers with larger cells in the pericarp,suggesting its promotion in both cell division and *** analyses between GA-3and mock-treated unpollinated ovaries/fruits identified a large number of differentially expressed genes related to hormones,cell division,cell expansion,and transcription factors,implying that they coordinately regulated parthenocarpy conferred by *** particular,the downregulation of five reported repressors of tomato parthenocarpy,including two auxin signaling components,AUXIN RESPONSE FACTOR5(SlARF5)and Sl ARF7,and three MADS-box genes,TOMATO APETALA3(TAP3),TOMATO PISTILLATA(TPI),and AGAMOUS-LIKE6(SlAGL6),after GA treatment might play a key role in this ***,we found that the knockdown of a GA signaling factor SlMYB33,which was depressed by GA treatment,induced parthenocarpic fruit set in tomato,an effect that might have been achieved by enhancing GA biosynthesis and decreasing the expression of some repressors of tomato ***,our results provide a basis for understanding the regulatory mechanism of GA in tomato parthenocarpy.

关键词： Tomato Gibberellin Parthenocarpy Histology Transcriptome SlMYB33

Static recrystallization behaviors and mechanisms of 7Mo super-austenitic stainless steel with undissolved sigma precipitates during double-stage hot deformation

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Journal of Iron and Steel Research International 2024年第2期31卷 475-487页

作者： Shi-guang Xu Jin-shan he run-ze Zhang Fu-cheng Zhang Xi-tao Wang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004HebeiChina Shandong Provincial Key Laboratory for High Strength Lightweight Metallic Materials Advanced Materials InstituteQilu University of Technology(Shandong Academy of Science)Jinan250353ShandongChina

Static recrystallization(SRX)behaviors and corresponding recrystallization mechanisms of 7Mo super-austenitic stainless steel were studied under different deformation *** order of influence of deformation parameters on static recrystallization behaviors,from high to low,is followed by temperature,first-stage strain and strain ***,the effect of holding time on static recrystallization behaviors is significantly controlled by *** addition,with the increase in temperature from 1000 to 1200°C,the static recrystallization mechanism evolves from discontinuous static recrystallization and continuous static recrystallization(cSRX)to metadynamic recrystallization and cSRX,and finally to *** cSRX exists at all *** is because high stacking fault energy(56 mJ m−2)promotes the movement of dislocations,making the deformation mechanism of this steel is dominated by planar slip of *** undissolved sigma precipitates promote static recrystallization through particle-stimulated ***,small strain-induced precipitates at grain boundaries hinder the nucleation of conventional SRX and the growth of recrystallized grains,while the hindering effect decreases with the increase in temperature.

关键词： 7Mo super-austenitic stainless steel Double-stage hot deformation Conventional static recrystallization Metadynamic recrystallization Strain-induced precipitation

Harnessing overlapped temperature-salinity gradient in solar-driven interfacial seawater evaporation for efficient steam and electricity generation

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Journal of Energy Chemistry 2024年第8期95卷 694-700,I0015页

作者： Peida Li Dongtong he Jingchang Sun Jieshan qiu Zhiyu Wang State Key Lab of Fine Chemicals Liaoning Key Lab for Energy Materials and Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina School of Physics and Electronic Technology Liaoning Normal UniversityDalian 116029LiaoningChina College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029China

Solar-driven interfacial water evaporation(SIWE)offers a superb way to leverage concentrated solar heat to minimize energy dissipation during seawater *** also engenders overlapped temperaturesalinity gradient(TSG)between water-air interface and adjacent seawater,affording opportunities of harnessing ***,the efficiency of conventional SIWE technologies is limited by significant challenges,including salt passivation to hinder evaporation and difficulties in exploiting overlapped TSG ***,we report self-sustaining hybrid SIWE for not only sustainable seawater desalination but also efficient electricity generation from *** enables spontaneous circulation of salt flux upon seawater evaporation,inducing a self-cleaning evaporative interface without salt passivation for stable steam ***,this design enables spatial separation and simultaneous utilization of overlapped TSG to enhance electricity *** benefits render a remarkable efficiency of90.8%in solar energy utilization,manifesting in co-generation of solar steam at a fast rate of 2.01 kg m^(-2)-h^(-1)and electricity power of 1.91 W m^(-2)with high *** interfacing the hybrid SIWE with seawater electrolyzer constructs a system for water-electricity-hydrogen co-generation without external electricity *** produces hydrogen at a rapid rate of 1.29 L h^(-1)m^(-2)and freshwater with 22 times lower Na+concentration than the World health Organization(WHO)threshold.

关键词： Solar-driven interfacial water evaporation Steam generation Electricity generation Seawater

An integrated MINLP model for multi-party coordination in downstream oil supply chain

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Petroleum Science 2024年第3期21卷 2066-2079页

作者： Rui qiu Bo Zhang Wei Zhao Ren-Fu Tu Man-qiu he Qi Liao Yong-Tu Liang National Engineering Laboratory for Pipeline Safety/Beijing Key Laboratory of Urban Oil and Gas Distribution Technology China University of Petroleum-BeijingFuxue Road No.18Changping DistrictBeijing102249PR China Strategy&Implementation Department PipeChinaDongtucheng Road No.5Chaoyang DistrictBeijing100013PR China

Cooperation among enterprises can bring overall and individual performance improvement,and a smooth coordination method is ***,due to the lack of customized coordination methods,cooperation in the downstream oil supply chain cannot be carried out *** paper intends to propose a multi-party coordination method to promote cooperation between oil shippers and pipeline operator by optimizing oil transportation,oil substitution and pipeline pricing *** integrated game-theoretic modeling and analysis approach is developed to characterize the operation behaviors of all stakeholders in the downstream oil supply *** proposed mixed integer nonlinear programming model constrains supply and demand capacity,transportation routes,oil substitution rules and pipeline freight *** transformation and price discretization are introduced for model linear *** experiments are carried out in the oil distribution system in South *** results show that compared to the business-as-usual scheme,the new scheme saves transportation cost by 3.48%,increases pipeline turnover by 5.7%,and reduces energy consumption and emissions by 7.66%and 6.77%.It is proved that the proposed method improves the revenue of the whole system,achieves fair revenue distribution,and also improves the energy and environmental benefits of the oil supply chain.

关键词： Downstreamoil supplychain Multi-partycoordination Cooperative game Mixed integernonlinear programming model Pipeline transportation Revenue distribution

一种新的MIMO-OFDM通信系统比特分配方案

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计算机工程与应用 2008年第11期44卷 133-135页

作者：张蓝星仇润鹤东华大学信息科学与技术学院上海201620

从MIMO-OFDM系统模型出发,首先对理想信道传输矩阵进行奇异值分解,在子信道自适应调制设计中应用信道矩阵特征值把空分复用信道转化为并行子信道,将用于多载波自适应比特分配算法应用于MIMO-OFDM系统。然后以实现系统发射功率最小为原则... 详细信息

从MIMO-OFDM系统模型出发,首先对理想信道传输矩阵进行奇异值分解,在子信道自适应调制设计中应用信道矩阵特征值把空分复用信道转化为并行子信道,将用于多载波自适应比特分配算法应用于MIMO-OFDM系统。然后以实现系统发射功率最小为原则,以降低系统比特分配算法复杂度为目标,提出了一种可变步长的子信道比特分配优化算法。仿真结果表明,这种算法不但可以实现和Campello方法相当的比特分配性能,还可以较大地降低系统的计算复杂度。

关键词： MIMO—OFDM 自适应调制比特分配

一种应用于无线城域网的OFDM帧同步新算法

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计算机工程与应用 2008年第13期44卷 87-89页

作者：张宁军仇润鹤东华大学信息科学与技术学院上海201620

以降低无线城域网OFDM帧同步算法计算复杂度为目标,提出了一种基于特殊加权序列的OFDM帧同步新算法,通过对发送序列和接收序列分别加权,使得在接收端能够得到尖锐的相关峰,准确判断OFDM符号的正确到达时刻;通过对加权序列的特殊规定使... 详细信息

以降低无线城域网OFDM帧同步算法计算复杂度为目标,提出了一种基于特殊加权序列的OFDM帧同步新算法,通过对发送序列和接收序列分别加权,使得在接收端能够得到尖锐的相关峰,准确判断OFDM符号的正确到达时刻;通过对加权序列的特殊规定使得系统能够采用迭代算法,从而最终使得计算复杂度大大降低。通过仿真分析可以证明,该算法既能够达到精确同步的要求,又具有较低计算复杂度且不易受频偏影响。

关键词：无线城域网 OFDM 帧同步加权序列

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MIMO-OFDM信道容量特性及仿真分析

计算机工程与应用 2007年第6期43卷 125-127页

作者：陈欣捷仇润鹤东华大学信息科学与技术学院上海200051

介绍了MIMO-OFDM的系统模型设计,重点分析了频率选择性衰落信道下的MIMO-OFDM信道容量,并通过计算机仿真探讨了信道相关性对其系统容量的影响。

关键词： MIMO—OFDM 信道容量相关性