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A HIGH-ORDER-ACCURATE DIFFERENCE SCHEME WITH UNCONDITIONAL STABILITY FOR THE DIFFUSION EQUATION ON NONUNIFORM GRIDS

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Journal of Hydrodynamics 2001年第1期13卷 92-98页

作者： Wang xuan, Yang Zhi-feng State Key Laboratory of Environment Simulation and Pollution Control, Institute of Environmental Sciences, Beijing Normal University, Beijing 100875, China[WT5”HZ] Beijing Normal Univ. Beijing 100875 China

WT5”BZ]A high-order-accurate difference scheme with unconditional stability is developed for the diffusion equation on nonuniform grids. The theoretical analysis shows that the accuracy of this scheme is between third order and fourth order, and fourth-order accuracy is achieved in the case of the same grid steps being used within the computational domain. Two numerical examples are given to demonst ate the advantages of the proposed scheme. Compared with the conventional difference scheme, more accurate numerical solution can be obtained by using the proposed scheme even with relatively larger grid sizes. It is also pointed out that the appropriate structure of the nonuniform grid can not only make the proposed scheme more practical, but lead to a solution superior to that for a uniform grid structure. [WT5”HZ]

关键词： ]finite difference scheme diffusion equation nonuniform grid high accuracy computational fluid dynamics

Application of FTA based on SDG-HAZOP for production of polypropylene

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中国安全生产科学技术 2013年第8期9卷 152-155页

作者： ZHAO Shi-ping CHEN Zheng-cai xuan Ai-guo HUANG Ting-ze School of Computer Sicence & Engineering Wuhan Institute of Technology School of Chemical Engineering & Pharmacy Wuhan Institute of Technology

The SDG-HAZOP(Signed Directed Graph,Hazard and Operability Analysis) is a qualitative safety assessment method,which is comprehensive,systematic and *** the result is tedious and *** tree analysis(FTA) is a logical and diagrammatic method,which is proved to be a useful quantitative analysis tool to evaluate the safety and reliability of complex *** a FTA based on SDG-HAZOP quantitative method was proposed in this ***,the SDG-HAZOP and the FTA were established on the background of polypropylene production devices in the Sinopec Wuhan ***,the probability of top event was calculated by reliable data from the probability of basic ***,the targeted measures were proposed to prevent fatal potential dangerous situations by probability calculation.

关键词： SDG-HAZOP fault tree analysis(FTA) polypropylene probability top event

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染料敏化太阳能电池对电极

物理化学学报 2011年第10期27卷 2255-2268页

作者：李靖孙明轩张晓艳崔晓莉复旦大学材料科学系上海200433

对电极是染料敏化太阳能电池的重要组成部分,改进对电极是提高其能量转换效率及降低成本的有效手段之一.本文重点综述了2008年以来染料敏化太阳能电池对电极的研究成果,详细介绍了各类对电极包括金属Pt、Au、Ni,纳米炭材料和导电聚合物... 详细信息

对电极是染料敏化太阳能电池的重要组成部分,改进对电极是提高其能量转换效率及降低成本的有效手段之一.本文重点综述了2008年以来染料敏化太阳能电池对电极的研究成果,详细介绍了各类对电极包括金属Pt、Au、Ni,纳米炭材料和导电聚合物等对电极的优点和制备工艺.Pt对电极性能最好,但是高成本限制了它在染料敏化太阳能电池产业化中的应用;新型的价格低廉、活性较高的纳米炭材料和导电聚合物及其复合材料等对电极在染料敏化太阳能电池的研究中逐渐引起人们的重视.

关键词：染料敏化太阳能电池:对电极:纳米Pt 纳米炭材料: 导电聚合物

Batch synthesis of transfer-free graphene with wafer-scale uniformity

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Nano Research 2020年第6期13卷 1564-1570页

作者： Bei Jiang Qiyue Zhao Zhepeng Zhang Bingzhi Liu Jingyuan Shan Liang Zhao Mark H.Rümmeli xuan Gao Yanfeng Zhang Tongjun Yu Jingyu Sun Zhongfan Liu Center for Nanochemistry(CNC) Beijing Science and Engineering Center for NanocarbonsCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China State Key Laboratory for Artificial Microstructures and Mesoscopic Physics School of PhysicsPeking UniversityBeijing100871China College of Energy Soochow Institute for Energy and Materials Innovations(SIEMIS)Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu ProvinceSoochow UniversitySuzhou215006China Beijing Graphene Institute(BGI) Beijing100095China

Scalable synthesis of transfer-free graphene over insulators offers exciting opportunity for next-generation electronics and ***,rational design of synthetic protocols to harvest wafer-scale production of directly grown graphene still remains a daunting *** we explore a batch synthesis of large-area graphene with wafer-scale uniformity by virtue of direct chemical vapor deposition(CVD)on *** a controllable CVD approach allows to synthesize 30 pieces of 4-inch graphene wafers in one batch,affording a low fluctuation of optical and electrical *** fluid dynamics simulations reveal the mechanism of uniform growth,indicating thermal field and confined flow field play leading roles in attaining the batch *** resulting wafer-scale graphene enables the direct utilization as key components in optical *** method is applicable to other types of insulating substrates(e.g.,sapphire,SiO2/Si,Si3N4),which may open a new avenue for direct manufacture of graphene wafers in an economic fashion.

关键词： graphene batch synthesis direct chemical vapor deposition(CVD) uniformity wafer-scale confined flow

Deuterium distribution and behavior of blisters in pre-damaged and undamaged tungsten

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Tungsten 2024年第3期6卷 647-656页

作者： Cong Li Xiao-Wa Wang Ran-Ran Su xuan-Xin Hu Shu-Guang Wei Han-Jun Tu Li-Qun Shi Hong-Liang Zhang Key Laboratory of Nuclear Physics and Ion-Beam Application Institute of Modern PhysicsFudan UniversityShanghai 200433China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Materials Science and Engineering University of WisconsinMadison WI 53706USA

Tungsten(W),as a plasma-facing material,is subjected to high fluence plasma,resulting in both radiation damage and deuterium(D)*** study explores the blistering behavior and D supersaturated layers in both pre-damaged and undamaged W *** achieve a uniform damage profile similar to neutron irradiation,carbon(C)ions with multiple energies and angles were *** samples were further irradiated with low-energy D ions under two fluences at temperatures from~380 to 640 *** various experimental techniques,we found that pre-damaged W samples can effectively suppress the formation of blistering and lower the threshold temperature at which the surface remains free of *** also observed the prominent D supersaturated peaks within the depth of 20 nm in both pre-damaged and undamaged ***,a close correlation between blistering and the D supersaturation was *** results suggest that neutron irradiation in the fusion reactors could increase the critical D concentration for blistering,while a greater depth of damage facilitated the inward diffusion of D,thereby reducing the D concentration gradient and alleviating surface blistering.

关键词： Tungsten Deuterium Supersaturated layer Blister Ion irradiation Pre-damage

A three-dimensional matrix system containing melatonin and neural stem cells repairs damage from traumatic brain injury in rats

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Neural Regeneration Research 2022年第11期17卷 2512-2517页

作者： xuan-Yu Fang Da-Wei Zhao Chao Zhang Hong-Fei Ge Xu-Yang Zhang Feng-Chun Zhao Yi-Bin Jiang Hua Feng Rong Hu Department of Neurosurgery and Key Laboratory of Neurotrauma Southwest HospitalArmy Medical UniversityChongqingChina

Brain lesions can cause neural stem cells to activate,proliferate,diffe rentiate,and migrate to the injured ***,after traumatic brain injury,brain tissue defects and microenvironment changes greatly affect the survival and growth of neural stem cells;the resulting reduction in the number of neural stem cells impedes effective repair of the injured *** can promote the survival,proliferation,and differentiation of neural stem cells under adverse conditions such as oxidative stress or hypoxia that can occur after traumatic brain ***,we investigated the therapeutic effects of melatonin combined with neural stem cells on traumatic brain injury in ***,in vitro studies confirmed that melatonin promoted the survival of neural stem cells deprived of oxygen and ***,we established a three-dimensional Matrigel-based transplantation system containing melatonin and neural stem cells and then used it to treat traumatic brain injury in *** found that treatment with the Matrigel system containing melatonin and neural stem cells decreased brain lesion volume,increased the number of surviving neuro ns,and improved recove ry of neurological function compared with treatment with Matrigel alone,neural stem cells alone,Matrigel and neural stem cells combined,and Matrigel and melatonin *** findings suggest that the three-dimensional Matrigelbased transplantation system containing melatonin and neural stem cells is a potential treatment for traumatic brain injury.

关键词： cell therapy magnetic resonance imaging Matrigel melatonin neural stem cells neurological function recovery three-dimensional transplantation traumatic brain injury

COR27 and COR28 encode nighttime repressors integrating Arabidopsis circadian clock and cold response

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Journal of Integrative Plant Biology 2017年第2期59卷 78-85页

作者： peng wang xuan cui chunsheng zhao liyan shi guowei zhang fenglong sun xiaofeng cao li yuan qiguang xie xiaodong xu hebei key laboratory of molecular and cellular biology key laboratory of molecular and cellular biology of ministry of educationcollege of life scienceshebei normal university hebei collaboration innovation center for cell signaling Shijiazhuang 050024China state key laboratory of plant genomics and national center for plant gene research institute of genetics and developmental biologychinese academy of sciencesBeijing 100101China

Summary It was noted that circadian components function in plant adaptation to diurnal temperature cycles and freezing tolerance. Our genome-wide transcriptome analysis revealed that evening-phased COR27 and COR28 mainly repress the transcription of clockassociated evening genes PRRS, ELF4 and cold-responsive genes. Chromatin immunoprecipitation indicated that CCAI is recruited to the site containing EE elements of COR27 and COR28 promoters in a temperaturedependent way. Further genetic analysis shows COR28 is essential for the circadian function of PRR9 and PRRT. Together, our results support a role of COR27 and COR28 as nighttime repressors integrating circadian clock and plant cold stress responses.

关键词： CCA COR27 and COR28 encode nighttime repressors integrating Arabidopsis circadian clock and cold response EE Figure

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基于浸没式光刻光束稳定系统的反射镜

光子学报 2019年第2期48卷 40-49页

作者：李美萱李宏张斯淇郭明付秀华吉林工程技术师范学院量子信息技术交叉学科研究院长春130052 吉林省量子信息技术工程实验室长春130052 长春理工大学光电工程学院长春130000

根据浸没式光刻系统的技术要求,设计了光束稳定系统,通过两个反射镜消除光束的位置漂移和指向漂移.基于深紫外材料特性,选择JGS1作为反射镜的基底,Al2O3和MgF2为高、低折射率薄膜材料.通过膜系设计软件完成了高反射膜的设计和模拟分析,... 详细信息

根据浸没式光刻系统的技术要求,设计了光束稳定系统,通过两个反射镜消除光束的位置漂移和指向漂移.基于深紫外材料特性,选择JGS1作为反射镜的基底,Al2O3和MgF2为高、低折射率薄膜材料.通过膜系设计软件完成了高反射膜的设计和模拟分析,并采用真空沉积技术研制了该薄膜.通过选择行星夹具镀膜设备和设计特定的补偿挡板来保证薄膜的非均匀性小于0.2%.测试了反射镜样片的光谱曲线和表面微观结构,结果表明研制的薄膜在45°入射时的反射率为98.5%,散射损耗为0.30%,满足系统使用要求.

关键词：光学薄膜光束稳定系统非均匀性吸收损耗散射损耗

The Earth Summit Mission-2022:Successful ozone soundings contribute to source identification in the north *** region

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Journal of Environmental Sciences 2024年第2期136卷 412-421页

作者： Jinqiang Zhang Chunxiang Ye Yuejian xuan Zhixuan Bai Weili Lin Dan Li Lingkun Ran Baofeng Jiao YaomingMa Weiqiang Ma Nan Yao Yunshu Zeng Daren Lv Tong Zhu Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Environmental Sciences and Engineering Center for Environment and HealthPeking UniversityBeijing 100871China Key Laboratory of Ecology and Environment in Minority Areas(Minzu University of China) National Ethnic Affairs CommissionBeijing 100081China Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Land-Atmosphere Interaction and Its Climatic Effects Group State Key Laboratory of Tibetan Plateau Earth SystemResources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China College of Atmospheric Science Lanzhou UniversityLanzhou 730000China National Observation and Research Station for Qomolongma Special Atmospheric Processes and Environmental Changes Dingri 858200China Kathmandu Center of Research and Education Chinese Academy of SciencesBeijing 100101China China-Pakistan Joint Research Center on Earth Sciences Chinese Academy of SciencesIslamabad 45320Pakistan Electronic Engineering College Chengdu University of Information TechnologyChengdu 610225China

As part of“The Earth Summit Mission-2022”during the second Tibetan Plateau Scientific Expedition and Research(STEP)in April and May 2022,we conducted the ozone sounding experiment(an ozonesonde mated to a radiosonde)at *** Base Camp(MQBC;86.85°E,28.14°N;5200 m),a location at an extremely high altitude.A total of ten sounding profiles were obtained between April 30 and May 06,2022,of which seven profiles were above35 km in altitude,with a maximum detection altitude up to 39.0 *** study presents the temporal variation and vertical distributions of atmospheric temperature,humidity,and ozone during the MQBC *** averaged ozone concentration was high(68.3 ppbv)at the surface and then increased smoothly until peaking(~110 ppbv)in the middle troposphere(approximately 10 km),and afterward,the ozone concentration increased rapidly from the upper troposphere to a maximum of~10 ppmv at~30 *** enhanced ozone concentration in the middle troposphere was associated with the blocking high pressure,and transport from the southern flank of the Himalayas occurred during the campaign *** average total ozone column was 291.9±21.4 DU for the seven profiles exceeding 35km in *** ozonesonde measurements were also compared with the vertical ozone profiles retrieved from the space-borne ozone products from the Microwave Limb Sounder(MLS)onboard the Aura satellite and the Atmospheric Infrared Sounder(AIRS)onboard the Aqua satellite.

关键词： Ozone soundings Mt.Qomolangma Vertical ozone structure Ozone source Satellite data