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CVD synthesis of nitrogen-doped graphene using urea

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Science China(Physics,Mechanics & Astronomy) 2015年第10期58卷 94-99页

作者： zhang cankun LIN WeiYi ZHAO ZhiJuan ZHUANG PingPing ZHAN LinJie ZHOU YingHui CAI WeiWei Department of Physics Laboratory of Nanoscale Condense Matter Physics and State Key Laboratory of Physical Chemistry of Solid SurfacesXiamen University

This work provides an effective low-cost synthesis and in-depth mechanistic study of high quality large-area nitrogen-doped graphene(NG) films. These films were synthesized using urea as nitrogen source and methane as carbon source, and were characterized by scanning electron microscopy(SEM), Raman spectroscopy and X-ray photoelectron spectroscopy(XPS). The N doping level was determined to be 3.72 at.%, and N atoms were suggested to mainly incorporated in a pyrrolic N configuration. All distinct Raman peaks display a shift due to the nitrogen-doping and compressive strain. The increase in urea concentration broadens the D and 2D peak's Full Width at Half Maximum(FWHM), due to the decrease of mean free path of phonons. The N-doped graphene exhibited an n-type doping behavior with a considerably high carrier mobility of about 74.1 cm2/(V s), confirmed by electrical transport measurements.

关键词：掺杂石墨尿素氮合成 X射线光电子能谱扫描电子显微镜声子平均自由程载流子迁移率拉曼光谱

Probing molecular orientation at bulk heterojunctions by polarization-selective transient absorption spectroscopy

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Science China Chemistry 2021年第9期64卷 1569-1576页

作者： cankun zhang Yuzhe zhang Zhiye Wang Yuming Su Zhixiang Wei Jianhui Hou Shan He Kaifeng Wu Chang He Jianqi zhang Cheng Wang State Key Laboratory for Physical Chemistry of Solid Surfaces iChEMCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) FuzhouChina CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanosciecneNational Center for Nanoscience and TechnologyBeijing100190China State Key Laboratory of Polymer Physics and Chemistry Institute of ChemistryChinese Academy of SciencesBeijing100190China State Key Laboratory of Molecular Reaction Dynamics and Dynamics Research Center for Energy and Environmental Materials Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China

A bulk heterojunction in organic solar cells is where charge separation and recombination *** orientation at the interface is one of the key factors that dictate solar cell *** X-ray scattering-based methods can determine donor/acceptor domain orientations between an anisotropic phase and an isotropic fullerene-based phase,the rise of nonfullerene solar cells presents a new challenge in delineating local molecular directions at the interface between two anisotropic donor/acceptor ***,we determine interfacial molecular orientations of three high-efficiency small molecule solar cells(ZR1:Y6,B1:BO-4 Cl,and BTR:BO-4 Cl)using polarization-selective transient absorption *** polarization anisotropy of charge separation dynamics indicates an angle of~90°between ZR1 and Y6 molecules at the interface,an angle close to 0°between B1 and BO-4 Cl,and random orientations between BTR and BO-4 *** observations provide complementary information to X-ray scattering measurements and highlight polarization-selective transient absorption spectroscopy as a tool to probe interfacial structure and dynamics of key photophysical steps in energy conversion.

关键词： polarization-selective transient absorption spectroscopy bulk heterojunction organic solar cell molecular orientation

Effects of three coniferous plantation species on plant-soil feedbacks and soil physical and chemical properties in semiarid mountain ecosystems

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Forest Ecosystems 2021年第1期8卷 22-34页

作者： Chun Han Yongjing Liu cankun zhang Yage Li Tairan Zhou Salman Khan Ning Chen Changming Zhao State Key Laboratory of Grassland and Agro-Ecosystems School of Life SciencesLanzhou University730000 LanzhouChina Gansu Provincial Field Scientific Observation and Research Station of Mountain Ecosystems 730000 LanzhouChina

Background:Large-scale afforestation can significantly change the ground cover and soil physicochemical properties,especially the soil fertility maintenance and water conservation functions of artificial forests,which are very important in semi-arid mountain ***,how different tree species affect soil nutrients and soil physicochemical properties after afforestation,and which is the best plantation species for improving soil fertility and water conservation functions remain largely ***:This study investigated the soil nutrient contents of three different plantations(Larix principis-rupprechtii,Picea crassifolia,Pinus tabuliformis),soils and plant-soil feedbacks,as well as the interactions between soil physicochemical ***:The results revealed that the leaves and litter layers strongly influenced soil nutrient availability through biogeochemical processes:*** had higher organic carbon,ratio of organic carbon to total nitrogen(C:N)and organic carbon to total phosphorus(C:P)in the leaves and litter layers than ***-rupprechtii or ***,suggesting that higher C:N and C:P hindered litter *** a result,the ***-rupprechtii and *** plantation forests significantly improved soil nutrients and clay components,compared with the *** plantation ***,the ***-rupprechtii and *** plantation forests significantly improved the soil capacity,soil total porosity,and capillary porosity,decreased soil bulk density,and enhanced water storage capacity,compared with the *** plantation *** results of this study showed that,the strong link between plants and soil was tightly coupled to C:N and C:P,and there was a close correlation between soil particle size distribution and soil physicochemical ***:Therefore,our results recommend planting the ***-rupprechtii and *** as the preferred tree species to enh

关键词： Plantation C:N:P stoichiometry Plant-soil feedbacks Soil physicochemical properties Mountain ecosystems

Isotope effect of the phonons mean free path in graphene by micro-Raman measurement

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Science China(Physics,Mechanics & Astronomy) 2014年第10期57卷 1817-1821页

作者： zhang cankun LI QiongYu TIAN Bo HUANG ZhiYi LIN WeiYi LI HongYang HE DaHai ZHOU YingHui CAI WeiWei Department of Physics Laboratory of Nanoscale Condense Matter Physics Xiamen University Xiamen G-CVD Material Technology Co. Ltd

The isotope labeled graphene was synthesized in the concentration of 13 C carbon atom in 1%, 25%, 50%, 75% and 99%. The isotope effect on the phonon behavior in graphene was investigated based on the micro-Raman analysis of 13 C isotope labeled graphene samples. We found that the phonon scattering is affected by the isotopic carbon atom as a point defect. Based on the experiment results, the Klemens-Callaway model and uncertainty principle were used to obtain the mean free path of the G and D phonons. The results agree with the thermal conductivity measurement by non-contact optical method and with other theoretical calculations.

关键词：同位素效应声子散射拉曼分析自由程石墨测量同位素标记不确定性原理

Derivation of Benzothiadiazine-1,1-dioxide Scaffolds via Transition Metal-Catalyzed C-H Activation/Annulation

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Chinese Journal of Chemistry 2023年第16期41卷 1973-1978页

作者： Ruizhi Lai Shuran Xu Qingyao zhang Hui Zhou cankun Luo Yuerong Wang Li Hai Yong Wu Key Laboratory of Drug Targeting and Drug Delivery System of the Education Ministry and Sichuan Province Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmagySichuan UniversityChengduSichuan 610041China

Comprehensive Summary Benzothiadiazine-1,1-dioxide scaffold is bioactive framework with wild utility and *** of benzothiadiazine-fused isoquinoline derivatives and spiro benzothiadiazine derivatives through transition metal-catalyzed C—H activation/annulation was reported.3-Phenyl-2H-benzothiadiazine-1,1-dioxide was used as the reaction substrate,and vinylene carbonate and 4-diazopyrazolone were used as the coupling reagents,*** strategy provides straightforward access to complex N-heterocycles in a highly efficient and simple manner.

关键词： C-H activation Annulation Ruthenium Rhodium Heterocycles Fused-ring systems Spiro compounds Diazo compounds

基于代谢重编程探讨慢性心力衰竭气虚血瘀病机实质

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现代中医临床 2024年第3期31卷 58-62页

作者：王梦妮龚胜兰姚灿坤蔡智刚胡嘉仪张天奉广州中医药大学第六临床医学院深圳518048 广州中医药大学深圳医院(福田)

慢性心力衰竭(简称慢心衰)是复杂的临床综合征,心脏作为维持机体新陈代谢的重要器官,其病理性重构与代谢异常密切相关。代谢重编程以物质与能量流向失衡为核心,贯穿于慢心衰病理演变的整个过程,其引发的心脏代偿性增殖及效应器官低效能... 详细信息

慢性心力衰竭(简称慢心衰)是复杂的临床综合征,心脏作为维持机体新陈代谢的重要器官,其病理性重构与代谢异常密切相关。代谢重编程以物质与能量流向失衡为核心,贯穿于慢心衰病理演变的整个过程,其引发的心脏代偿性增殖及效应器官低效能与气虚血瘀表征关联。益气活血化瘀法作为治疗慢心衰的重要治法,通过标本同治,恢复心脏的代谢灵活性,重塑代谢重编程。本文以代谢重编程为切入点,探讨慢心衰气虚血瘀病机的实质,为益气活血化瘀法治疗慢心衰的机制研究提供依据。

关键词：慢性心力衰竭代谢重编程气虚血瘀

全球遥感实时监测与定点更新云平台设计与实现

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遥感学报 2022年第2期26卷 324-334页

作者：钟若飞李清扬周春平李小娟杨灿坤张思赵可杜雨首都师范大学资源环境与旅游学院北京100048 首都师范大学三维信息获取与应用教育部重点实验室北京100048 北京遥感信息研究所北京100048

卫星遥感是人类观测地球的主要途径,随着遥感技术商业化,全球商业遥感卫星数量快速增长,涌现出许多高分辨率遥感卫星和全球遥感星座,使用卫星对地球进行更全面、更精确、更实时的监测成为可能,但目前卫星遥感数据获取存在重复、盲目、... 详细信息

卫星遥感是人类观测地球的主要途径,随着遥感技术商业化,全球商业遥感卫星数量快速增长,涌现出许多高分辨率遥感卫星和全球遥感星座,使用卫星对地球进行更全面、更精确、更实时的监测成为可能,但目前卫星遥感数据获取存在重复、盲目、不及时,与用户需求脱节、大量数据闲置等一系列问题,缺乏一个有效的平台和应用模式,搭起卫星数据提供商和用户之间的桥梁。本文基于只需对变化信息进行定向监测和更新即可实现对地表实时监测这一前提出发,提出了一套卫星遥感和互联网结合的地球实时变化监测在线服务云平台,平台通过以用户感兴趣区域的自动变化检测技术为核心,汇聚用户对地表变化信息的需求,形成更高清的卫星拍摄条件,按轨道预测模型优先向最邻近拍摄点的卫星数据服务商快速推送卫星拍摄指令,实现定点定向数据更新,以保证用户随时可以查看感兴趣区域的地表最新影像。其核心思想主要是基于互联网在线抓取技术、云平台的自动变化检测技术与卫星在轨处理实时感知技术来分析、挖掘、提取地理实体变化情报,通过实时推送卫星拍摄指令来实现基于变化信息的定向、定点地理实体数据的采集和更新,保持对感兴趣区域的实时监测服务。本文阐述了云平台建设过程中的实现方法,构建了云平台的基本原型并对其进行验证,讨论了云平台中新的总体架构设计思想和应用领域等问题,展示了该平台对目前商业遥感服务中存在的被动性、单一性、延迟性、重复性等问题的解决方案,提供了一种以传统数据查询订购的云平台向基于变化信息实时监测与定点更新服务云平台跨越的设计思路。

关键词：遥感星地协同变化检测星上处理云平台定点更新

环氧树脂/碳化硼复合材料耐辐射和热老化性能研究

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材料导报 2023年第23期37卷 221-226页

作者：张城皓王硕珏田琳谷潇夏曹可张龙马灿坤王连才马慧玲张秀芹北京服装学院材料设计与工程学院北京市服装材料研究开发与评价北京市重点实验室北京市纺织纳米纤维工程技术研究中心北京100029 航天材料及工艺研究所北京100076 北京市射线应用研究中心辐射新材料北京市重点实验室北京100015

本工作以环氧树脂为基体,碳化硼为中子吸收填料,采用高效的固化成型方法制备了环氧树脂/碳化硼复合屏蔽材料。通过扫描电镜(SEM)、差示扫描量热法(DSC)和热失重法(TGA)分析碳化硼含量对复合材料微观结构、固化程度和热稳定性的影响;通... 详细信息

本工作以环氧树脂为基体,碳化硼为中子吸收填料,采用高效的固化成型方法制备了环氧树脂/碳化硼复合屏蔽材料。通过扫描电镜(SEM)、差示扫描量热法(DSC)和热失重法(TGA)分析碳化硼含量对复合材料微观结构、固化程度和热稳定性的影响;通过辐照和热老化前后样品拉伸和冲击性能的测试探究了材料的辐射稳定性和热老化性能。实验结果表明:碳化硼粉体能均匀地分散在环氧树脂基体中;经过150℃不同时间的热老化测试和100 kGy辐照实验,复合材料的力学性能略有降低。采用SuperMC软件模拟计算了复合材料对热中子和慢中子的屏蔽性能,当复合材料厚度为5 mm时,复合材料对热中子和慢中子的屏蔽效率分别为99%和63%,此材料有望作为一种新型的屏蔽材料应用于乏燃料贮存罐中。

关键词：环氧树脂碳化硼耐高温中子屏蔽蒙特卡罗模拟计算(MCNP)

高分辨率光学卫星图像目标运动信息提取研究综述

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国土资源遥感 2019年第3期31卷 1-9页

作者：李想杨灿坤周春平李小娟张可首都师范大学北京成像技术高精尖创新中心北京100048 首都师范大学资源环境与旅游学院北京100048 首都师范大学三维信息获取与应用教育部重点实验室北京100048

目标运动信息提取技术是指利用卫星遥感检测地面移动目标并估计其运动参数,在智能交通、军事遥感等方面应用广泛,是遥感图像应用的重要方向之一。高分辨率光学卫星图像中动目标的纹理特征更明显,包含的信息更丰富,是大范围目标运动特征... 详细信息

目标运动信息提取技术是指利用卫星遥感检测地面移动目标并估计其运动参数,在智能交通、军事遥感等方面应用广泛,是遥感图像应用的重要方向之一。高分辨率光学卫星图像中动目标的纹理特征更明显,包含的信息更丰富,是大范围目标运动特征研究的良好数据。首先,总结了光学卫星图像动目标研究进展;然后,将高分辨率光学卫星图像目标运动信息提取过程分为动目标检测和运动参数估计2部分,并分别进行算法综述;除已有算法外,还介绍了基于序列全色卫星图像的新型动目标检测方法的原理与思路;最后,分析了已有研究在数据源和算法方面的不足,指出目标运动信息提取向自动化、智能化、实时化发展的趋势。

关键词：高分辨率遥感光学卫星图像多模态传感器全色波段动目标检测运动参数估计