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Influence of recrystallization on tungsten divertor monoblock under high heat flux

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Tungsten 2022年第3期4卷 194-202页

作者： yu-zhong jin Xiang Liu You-yun Lian Jiu-Peng Song Southwestern Institute of Physics Chengdu610225China Xiamen Tungsten Co.Ltd Xiamen361021China

Extremely high heat flux reaching 20 MW·m^(−2) can be foreseen for the future fusion *** high heat flux would induce recrystallization of tungsten(W)material,leading to significant strength loss of tungsten material and increment of ductility at high temperature,in particular when the temperature is much higher than its ductile-to-brittle transition temperature(DBTT).In this paper,an International Thermonuclear Experimental Reactor(ITER)-like tungsten divertor monoblock is modeled,and benchmark has been done first to get consistent results with ***,the monoblock structure has been optimized in order to get a lowest possible temperature and stress during heating and cooling phase separately compared to the baseline *** analysis of two kinds of states:stress-relieved tungsten and recrystallized tungsten using finite element method has been performed,aiming at finding out the recrystallization impact on the mechanical behavior of tungsten in divertor monoblock under cyclic high heat *** due to progressive deformation and time-independent fatigue lifetime of these two states of tungsten have been assessed and compared according to criteria The Structural Design Criteria for ITER In-vessel ***,the impact of different material recrystallization temperature on mechanical behavior has been explored under stationary heat *** result shows that after recrystallization,thermal stress of tungsten material can be released by the larger plastic deformation compared to the stress-relieved ***,it is easier for recrystallized tungsten to get damaged due to progressive deformation as well as fatigue under 20 MW·m^(−2) cyclic heat flux than stress-relieved tungsten because of its relatively lower yield strength and larger plastic strain,which would cause low-cycle strain ***,tungsten with lower recrystallization temperature distorts more seriously,and therefore,it can be predicted the cracks would

关键词： Tungsten Finite element method Divertor High heat flux Thermal stress

A Compact and Highly Efficient Silicon-Based Asymmetric Mach–Zehnder Modulator with Broadband Spectral Operation

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Chinese Physics Letters 2011年第7期28卷 122-125页

作者： ZHOU Liang LI Zhi-Yong XIAO Xi XU Hai-Hua FAN zhong-Chao HAN Wei-Hua yu yu-De yu jin-zhong State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083 Engineering Research Center for Semiconductor Integrated Technology Institute of SemiconductorsChinese Academy of SciencesBeijing 100083

An asymmetric Mach–Zehnder electro-optic modulator is demonstrated by using a silicon-based p-i-n diode embedded in compact 200µm long phase *** measured figure of merit VπL=0.23 V⋅mm shows highly efficient modulation by the device,and an open eye−diagram at 3.2 Gbit/s confirmed its fast electro-optic *** with the grating coupler,the device exhibits a broad operational wavelength range of 70 nm with a uniform 18 dB extinction ratio covering the C−band and part L-band of optical communication.

关键词： modulator Highly Compact

Silicon-on-Insulator Based 2 × 2 Multimode Interference Coupler with Large Tolerance

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Chinese Physics Letters 2001年第2期18卷 245-247页

作者： WEI Hong-Zhen yu jin-zhong LIU zhong-Li ZHANG Xiao-Feng SHI Wei FANG Chang-Shui State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083 Microelectronics Center Institute of SemiconductorsChinese Academy of SciencesBeijing 100083 State Key Laboratory of Crystal Materials Shandong UniversityJi’nan 250100

We demonstrate a type of 2 × 2 multimode interference 3 dB coupler based on *** fabrication tolerance was investigated by the effective index method and the guide mode *** devices with different lengths were fabricated and near-field output images were *** to width,length and etch depth are 2,200 and 2μm,*** devices show a uniform power distribution.

关键词： 2μm Interference Tolerance

Pollinator-dependent evolution of floral trait combinations in an orchid herb

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Journal of Plant Ecology 2020年第4期13卷 450-459页

作者： yun Wu Xu-yu Duan Yong Xiang Shao-Bin Weng jin-yu zhong jing Li Qing-Jun Li School of Civil Engineering Architecture and EnvironmentXihua UniversityChengdu 610039China yunnan Key Laboratory of Plant Reproductive Adaption and Evolutionary Ecology Kunming 650091China Laboratory of Ecology and Evolutionary Biology Yunnan UniversityKunming 650091China South-East Tibetan Plateau Station for Integrated Observation and Research of Alpine Environment Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China College of Landscape Architecture Sichuan Agricultural UniversityChengdu 611130China

Aims As one of the most important agents driving floral evolution,pollinators shape the diversity of flowers in ***,most previous studies have only quantified pollinators driving the evolution of a single floral trait,and experimental estimates of the potential role of pollinators in shaping the evolution of floral trait associations are relatively *** We experimentally identified and estimated the pollinator-mediated directional and correlational selection on single floral traits and trait combinations across 2 years in an orchid species,Spiranthes *** Findings Pollinators mediated directional selection for an earlier flowering start date and larger corolla *** mediated positive correlational selection on the combinations of floral display traits and negative correlational selection on the combinations of flowering phenology and floral display *** addition,the strength of selection differed over *** results highlight the potential role of pollinators in driving the evolution of floral trait combinations and suggest that it is necessary to consider floral character functional associations when seeking to understand and predict the evolutionary trajectory of flowers in angiosperms.

关键词： directional and correlational selection floral evolution pollinator-mediated selection Spiranthes sinensis trait combinations

Optimization of silicon-on-insulator based optical switch using tapered waveguides

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Optoelectronics Letters 2007年第5期3卷 326-328页

作者： LI Zhi-yong CHEN Shao-wu yu jin-zhong State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing100083 China

Optimized 2×2 switches based on silicon-on-insulator (SOI) were demonstrated. In the design, single mode rib waveguidesand multimode interferences (MMIs) are connected by tapered waveguides to reduce the mode coupling loss between thetwo types of waveguides. The average insertion loss of the switches is about -16.9 dB and the excess loss of one is measuredof -1.3 dB. The worst crosstalk is larger than 25 dB. Experimental results indicate that some of the main characteristics ofoptical switches are improved in the modified design, which is according with theoretic analysis. The novel design can beused to improve the characteristics of optical switch matrixes based on 2×2 switch units.

关键词：光学开关集成电路波导绝缘体

AlGaN/GaN HEMTs on 4-Inch Silicon Substrates in the Presence of 2.7-μm -Thick Epilayers with the Maximum Off-State Breakdown Voltage of 500 V

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Chinese Physics Letters 2014年第3期31卷 129-132页

作者： yu Xin-Xin NI jin-yu LI zhong-Hui KONG Cen ZHOU Jian-Jun DONG Xun PAN Lei KONG yue-Chan CHEN Tang-Sheng Science and Technology on Monolithic Integrated Circuits and Modules Laboratory Nanjing Electronic Devices Institute Nanjing 210016

We report on the high breakdown performance of AlGaN/GaN high electron mobility transistors （HEMTs） grown on 4-inch silicon substrates. The HEMT structure including three Al-content step-graded AlGaN transition layers has a total thickness of 2.7 μm. The HEMT with a gate width WG of 300 μm acquires a maximum off-state breakdown voltage （BV） of 550 V and a maximum drain current of 527 mA/mm at a gate voltage of 2 V. It is found that BV is improved with the increase of gate-drain distance LGD until it exceeds 8 μm and then BV is tended to saturation. While the maximum drain current drops continuously with the increase of LGD. The HEMT with a WG of 3 mm and a LGD of 8 μm obtains an off-state BV of 500 V. Its maximum leakage current is just 13 μA when the drain voltage is below 400 V. The device exhibits a maximum output current of 1 A with a maximum transconductance of 242 mS.

关键词： High electron mobility transistors

High Efficiency Grating Coupler for Coupling between Single-Mode Fiber and SOI Waveguides

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Chinese Physics Letters 2013年第1期30卷 99-102页

作者： ZHANG Can SUN jing-Hua XIAO Xi SUN Wei-Min ZHANG Xiao-Jun CHU Tao yu jin-zhong yu yu-De College of Science Harbin Engineering UniversityHarbin 150001 State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083

A high efficiency grating coupler between single-mode fiber and silicon-on-insulator waveguide is designed by a formula *** 78.5%coupling efficiency(>-1.05 dB)with 3 dB bandwidth about 50 nm for one grating coupler is obtained experimentally and this result is the highest one as far as we *** grating coupler is CMOS compatible which needs only one etch-step and is designed for a standard SOI chip without any Bragg reflector or bottom reflector.

关键词： SOI waveguide Efficiency

Thermally Stable Guest-Host Polyetherketone Poled Polymer for Electro-Optical Applications

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Chinese Physics Letters 2002年第8期19卷 1125-1127页

作者： Pan Qi-Wei Fang Chang-Shui Qin Zhi-Hui Gu Qing-Tian Wu Xiang-Wen Shi Wei yu jin-zhong State Key Laboratory of Crystal Materials Shandong University Ji'nan 250100 State Key Laboratory on Integrated Optoelectronics of Semiconductor Chinese Academy of Sciences Beijing 100083

The high glass transition temperature polymer polyetherketone doped with disperse red 13 (DR13/PEK-c) has been prepared by the spin-coating method. Through in situ second-harmonic generation, the corona poling temperature was optimized by measuring the temperature dependence of the in situ second-harmonic generation signal intensity under the poling electric field. The linear electro-optic coefficients of the poled polymer films have been determined at 632.8nm by using a simple interferometric technique. The polymer system was measured after 13000h, and found that it remained at 80% of its initial value.

关键词： Harmonic generation

Dynamic Regulation of Hydrogen Bonding Networks and Solvation Structures for Synergistic Solar‑Thermal Desalination of Seawater and Catalytic Degradation of Organic Pollutants

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Nano-Micro Letters 2025年第2期17卷 548-565页

作者： Ming‑yuan yu jing Wu Guang Yin Fan‑Zhen Jiao zhong‑Zhen yu jin Qu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Although solar steam generation strategy is efficient in desalinating seawater,it is still challenging to achieve continuous solar-thermal desalination of seawater and catalytic degradation of organic ***,dynamic regulations of hydrogen bonding networks and solvation structures are realized by designing an asymmetric bilayer membrane consisting of a bacterial cellulose/carbon nanotube/Co_(2)(OH)_(2)CO_(3)nanorod top layer and a bacterial cellulose/Co_(2)(OH)_(2)CO_(3)nanorod(BCH)bottom ***,the hydrogen bonding networks inside the membrane can be tuned by the rich surface–OH groups of the bacterial cellulose and Co_(2)(OH)_(2)CO_(3)as well as the ions and radicals in situ generated during the catalysis ***,both SO_(4)^(2−)and HSO_(5)−can regulate the solvation structure of Na^(+)and be adsorbed more preferentially on the evaporation surface than Cl^(−),thus hindering the de-solvation of the solvated Na^(+)and subsequent nucleation/growth of ***,the heat generated by the solar-thermal energy conversion can accelerate the reaction kinetics and enhance the catalytic degradation *** work provides a flow-bed water purification system with an asymmetric solar-thermal and catalytic membrane for synergistic solar thermal desalination of seawater/brine and catalytic degradation of organic pollutants.

关键词： Solar steam generation Seawater desalination Catalytic degradation Bacterial cellulose Cobalt hydroxycarbonate nanorods