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Porous n-doped-carbon coated CoSe2 anchored on carbon cloth as 3D photocathode for dye-sensitized solar cell with efficiency and stability outperforming Pt

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nano Research 2019年第1期12卷 159-163页

作者： Wenli Lu Rui Jiang Xiong Yin leyu wang State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University oj Chemical TechnologyBeijing 100029China

Photocathode with superior catalytic activity,long-term stability,and fast mass/electron transfer is highly desirable but challenging for dye-sensitized solar cell(DSC).Herein,the ZIF-67 grown on carbon cloth is successfully transformed into CoSe2 embedded in n-doped carb on nano cage(CoSe2/n-C)via a growth-carbonization-selenization *** carb on cloth supported CoSe2/n-C,as photocathode of DSC,demonstrates a good long-term stability and high photovoltaic efficiency(8.40%),outperforming *** good efficiency can be attributed to the high catalytic activity of CoSe2,fast mass tran sfer of porous three-dimensi on al(3D)structure,and good electr on transport derived from the intimate con tact between CoSe2 and highly conductive carb on *** high stability would be ascribed to n-doped carbon coating that perfectly prevents CoSe2 from *** work will pave the way to develop highly efficient and stable Pt-free photocathode for DSC.

关键词： three-dimensional(3D)photocathode metal-organic framework selenization process CoSe2 carbon cloth tri-iodide reduction reaction

Superfluorinated copper sulfide nanoprobes for simultaneous 19F magnetic resonance imaging and photothermal ablation

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nano Research 2016年第6期9卷 1630-1638页

作者： Gaofei Hu Juan Tang Xilin Bai Suying Xu leyu wang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China

Copper sulfide （Cu7S4） nanoparticles coated with an ultra-high payload （n5.0 ~ 107 fluorine atoms per particle） of fluorinated ligands （oleylamine functionalized 3,5-bis（trifluoromethyl）benzaldehyde, 19FOAm） exhibited a single intense 19F magnetic resonance （MR） signal and efficient near infrared photothermal performance in water medium. In vivo assessment revealed strong 19F MR signals at cancerous lesions and effective inhibition of tumor growth after photothermal treatment, indicating the great potential of these fabricated nanoprobes for simultaneous 19F MR imaging and photothermal therapy.

关键词： 19F magnetic resonance imaging photothermal therapy

Organic nanoprobes for Fluorescence and ^19F Magnetic Resonance DuaI-Modality Imaging

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Chinese Journal of Chemistry 2018年第1期36卷 25-30页

作者： Minmin Xu Chang Guo Gaofei Hu Suying Xu leyu wang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China

Multimodal imaging techniques have been demonstrated to be greatly advantageous in achieving accurate diagnosis and gained increasing attention in recent decades. Herein, we present a new strategy to integrate the complementary modalities of I9F magnetic resonance imaging （19F MRI） and fluorescence imaging （FI） into a polymer nanoprobe composed of hydrophobic fluorescent organic core and hydrophilic fluorinated polymer shell. The alkyne-terminated fluorinated copolymer （Pn） of 2,2,2-trifluoroethyl acrylate （TFEA） and poly（ethylene glycol） methyl ether acrylate （PEGA） was first prepared vie atom transfer radical polymerization （ATRP）. The PEGA plays an important role in both improving ^19F signal and modulating the hydrophilicity of Pn. The alkynyl tail in Pn is readily conjugated with azide modified tetra-phenylethylene （TPE） through click chemistry to form azo polymer （TPE-azo-Pn）. The core-shell nanoprobes （TPE-P3n） with an average particle size of 57.2±8.8 nm are obtained via self-assembly with ultrasonication in aqueous solution. These nanoprobes demonstrate high water stability, good biocompatibility, strong fluorescence and good ^19F MRI performance, which present great potentials for simultaneous fluorescence imaging and ^19F-MR imaging.

关键词： organic nanoprobes, ^19F magnetic resonance imaging fluorescence imaging dual-modality imaging

Intensifying uneven charge distribution via geometric distortion engineering in atomically dispersed M-n_(x)/S sites for efficient oxygen electroreduction

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nano Research 2022年第10期15卷 8928-8935页

作者： Zhuting Zhang Simin Yang Rui Jiang Tian Sheng Chunfeng Shi Yueguang Chen leyu wang State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China College of Chemistry and Materials Science Anhui Normal UniversityWuhu 214000China Research Institute of Petroleum Processing SINOPECBeijing 100083China

Fine regulation of geometric structures has great promise to acquire specific electronic structures and improve the catalytic performance of single-atom catalysts,yet it remains a ***,a novel seed encapsulation–decomposition strategy is proposed for the geometric distortion engineering and thermal atomization of a series of Cu-n_(x)/S moieties anchored on carbon *** pyrolysis,seeds(Cu^(2+),CuO,or Cu_(7)S_(4) nanoparticles)confined in metal organic framework can accommodate single Cu atoms with Cu–n or Cu–S coordination bonds and simultaneously induce C–S or C–n bond cleavage in the second coordination shell of Cu centers,which are identified to manipulate the distortion degree of Cu-n_(x)/S *** severely distorted Cu-n3S molecular structure endows the resultant catalyst with excellent oxygen reduction reaction activity(E_(1/2)=0.885 V)and zinc-air battery performance(peak power density of 210 mW·cm^(−2)),outperforming the asymmetrical and symmetrical Cu-n4 structures.A combined experimental and theoretical study reveals that the geometric distortion of Cu-n_(x)/S moieties creates uneven charge distribution by a unique topological correlation effect,which increases the metal charge and shifts the d-band center toward the Fermi level,thereby optimizing the inter-mediate adsorption energy.

关键词： single-atomic sites geometric distortion engineering seed encapsulation-decomposition strategy charge distribution oxygen reduction reaction

Hydrophilic perovskite microdisks with excellent stability and strong fluorescence for recyclable temperature sensing

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Science China Materials 2019年第7期62卷 1065-1070页

作者： Qing Luo Hui wang Xiong Yin leyu wang State Key Laboratory of Chemical Resource Engineering Innovation Centre for Soft Matter Science and Engineering Beijing University of Chemical Technology

In recent years, metal halide perovskites have emerged as a promising new class of semiconductors for solar cells [1-3], light-emitting diodes (LED)[4-6], temperature sensors [7], lasers [8] and photodetectors [9], owing to their excellent optical and electronic properties [10,11], such as, long charge carrier diffusion length [12], high extinction coefficients and tunable band gaps [13]. However, the materials suffer from fast degradation due to their inherent instability [14-17], especially high sensitivity to oxygen [18], UV light [19,20], heat [21,22], moisture [23,24] and even some hydrophilic solvents such as alcohol, which significantly impedes their further applications [25,26]. Compared with organicinorganic hybrid perovskites [27], all-inorganic cesium lead halide perovskites CsPbX3 (X=C1, Br, I) are much stable [28-33], but the stability still needs substantial improvement to satisfy the needs of practical implications.

关键词：制备技术传感性能钙钛矿薄片亲水超稳定荧光二甲基甲酰胺

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超低轨卫星气动舵机辅助姿态控制方法设计

北京航空航天大学学报 2023年第3期49卷 548-558页

作者：王涛焦洪臣刘杰陈乐宇张迎春哈尔滨工业大学航天学院哈尔滨150001 中国空间技术研究院遥感卫星总体部北京100094 北京航空航天大学宇航学院北京100191

针对超低轨卫星姿态控制差异化需求,开展了基于气动舵机辅助的姿态控制策略研究。完成了超低轨道稀薄大气下卫星气动舵机布局设计与气动特性研究,理论气动力可达10^(-1) n量级,气动力矩可达10^(-1) n·m量级。在此基础上,完成了基于气... 详细信息

针对超低轨卫星姿态控制差异化需求,开展了基于气动舵机辅助的姿态控制策略研究。完成了超低轨道稀薄大气下卫星气动舵机布局设计与气动特性研究,理论气动力可达10^(-1) n量级,气动力矩可达10^(-1) n·m量级。在此基础上,完成了基于气动舵机辅助的姿态控制策略研究。通过仿真验证,在x轴采用动量轮控制、y轴和z轴采用气动舵机辅助控制情况下,可实现优于0.004°的三轴指向精度和优于0.0007(°)/s的三轴姿态稳定度。所设计气动舵机辅助姿态控制策略对超低轨卫星技术应用与发展具有重要技术价值和工程意义。

关键词：超低轨卫星气动舵机空气动力学姿态控制卫星构型

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高等院校文科学生个性作业研究

内蒙古财经学院学报（综合版） 2009年第1期7卷 22-26页

作者：王乐宇内蒙古财经学院法学系内蒙古呼和浩特010051

在高等院校的文科教学中,作业始终是一个非常薄弱的环节。值得注意的是,作业问题并未引起专家、学者们的足够重视,既缺乏行之有效的专项研究,在教育部及各高校的规章制度中亦鲜有深掘。笔者认为:加强个性作业研究是提高高校文科学生作... 详细信息

在高等院校的文科教学中,作业始终是一个非常薄弱的环节。值得注意的是,作业问题并未引起专家、学者们的足够重视,既缺乏行之有效的专项研究,在教育部及各高校的规章制度中亦鲜有深掘。笔者认为:加强个性作业研究是提高高校文科学生作业质量的根本出路。同时,提出了高校文科学生个性作业运作机制的具体构想。

关键词：文科教学共性作业个性作业创新

罩式炉退火温度对nb-Ti复合IF钢组织及性能的影响

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金属热处理 2018年第3期43卷 171-176页

作者：韩玉龙周乐育包头钢铁股份有限公司薄板坯连铸连轧厂内蒙古包头014010 北京科技大学材料科学与工程学院北京100083 北京机电研究所有限公司北京100083

通过加热炉模拟试验、组织观察、性能测试以及X射线衍射分析,研究了nb-Ti复合IF钢的再结晶温度,并根据该温度范围制定合理的罩式退火工艺,研究了保温温度对试验钢组织性能的影响。结果表明：试验钢的再结晶开始温度为600℃,终止温度为66... 详细信息

通过加热炉模拟试验、组织观察、性能测试以及X射线衍射分析,研究了nb-Ti复合IF钢的再结晶温度,并根据该温度范围制定合理的罩式退火工艺,研究了保温温度对试验钢组织性能的影响。结果表明：试验钢的再结晶开始温度为600℃,终止温度为660℃,再结晶时间为1.2 h左右。在再结晶温度以上退火后,组织为等轴状铁素体,随保温温度上升,晶粒尺寸略有增加,晶粒度级别在8~9级之间,属于有利于冲压的晶粒尺寸范围。随着保温温度的升高,A_（80）值有所上升,从41%增长到44%;Δr值下降,从0.19下降到0.03。R_（e L）、R_m、n值变化不大,r值得到改善,从2.18增长到2.35。织构方面,随着保温温度的上升,有利织构组分{001}〈110〉、{112}〈110〉进一步向{111}〈110〉、{111}〈112〉转化。罩式退火保温温度为710℃时,IF钢综合力学性能最优。

关键词： nb-Ti复合IF钢退火温度再结晶组织性能织构

应激引起不同年龄、性别和种类小鼠免疫器官退化的比较研究

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北京大学学报（自然科学版） 2000年第5期36卷 725-731页

作者：肖健张晏耿晓峰吴振宇王勒渝北京大学心理系北京100871 北京广安门医院基础医学研究室北京100053

以警告信号加足底电击的方式 (简称信号电击 )对不同年龄、性别和种类小鼠进行应激 ,每天 2 4min ,共 7d。结果发现 ,应激后免疫器官退化 ,重量减轻 ,而且这种变化与年龄和性别有关。胸腺退化 ,年龄大的鼠比年龄小的鼠更明显 ,而脾脏则... 详细信息

以警告信号加足底电击的方式 (简称信号电击 )对不同年龄、性别和种类小鼠进行应激 ,每天 2 4min ,共 7d。结果发现 ,应激后免疫器官退化 ,重量减轻 ,而且这种变化与年龄和性别有关。胸腺退化 ,年龄大的鼠比年龄小的鼠更明显 ,而脾脏则相反 ,年龄小的鼠更敏感。另外 ,胸腺的退化雄性要高于雌性 ,而脾脏则没有性别上的差异。从种类上看 ,Swiss鼠比Balb/c鼠更敏感。对淋巴结来说 ,这种退化没有表现出年龄、性别和种类的差异。此外 ,应激使胸腺、脾脏内的淋巴细胞总数和骨髓内淋巴细胞的比例减少。这一结果说明 ,胸腺和脾脏的退化 ,不是由于组织内体液的减少 ,而是胸腺和脾脏内淋巴细胞绝对数减少之故。

关键词：应激胸腺脾脏退化免疫器官年龄性别小鼠