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拉伸应变率对20钢层裂特性的影响

爆炸与冲击 2007年第3期27卷 193-197页

作者：王永刚贺红亮中国工程物理研究院流体物理研究所冲击波物理与爆轰物理实验室

采用轻气炮加载技术和激光速度干涉(VISAR)测速技术相结合,对不同拉伸应变率条件下20钢的层裂特性进行了实验研究。通过改变飞片和样品的几何尺寸来调整拉伸应变率的大小,研究了拉伸应变率对20钢层裂强度的影响。实验的拉伸应变率的变... 详细信息

采用轻气炮加载技术和激光速度干涉(VISAR)测速技术相结合,对不同拉伸应变率条件下20钢的层裂特性进行了实验研究。通过改变飞片和样品的几何尺寸来调整拉伸应变率的大小,研究了拉伸应变率对20钢层裂强度的影响。实验的拉伸应变率的变化范围为104～106s-1,最大拉伸应变率接近激光加载所能产生的拉伸应变率,相比激光加载,薄飞片技术容易保证一维应变条件。实验结果显示20钢的层裂特性明显依赖着拉伸应变率的大小,106s-1条件下层裂强度比104s-1时提高近70%。基于对数值计算结果的分析,讨论了影响层裂强度的主要外载荷因素。

关键词：固体力学拉伸应变率层裂 20钢

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煤料的粒度对型焦抗压强度的影响

煤炭学报 2007年第4期32卷 441-444页

作者：马名杰王永刚周翔中国矿业大学(北京)化学与环境工程学院

以气煤和弱粘煤半焦为原料,通过改变气煤和弱粘结煤半焦的粒度制备出一系列的型焦.研究了煤料粒度对型焦抗压强度的影响.研究结果表明,当半焦粒度固定不变时,随着气煤的粒度增大,型焦的抗压强度增加,气煤粒度在0.5-0.9 mm之间,型焦的抗... 详细信息

以气煤和弱粘煤半焦为原料,通过改变气煤和弱粘结煤半焦的粒度制备出一系列的型焦.研究了煤料粒度对型焦抗压强度的影响.研究结果表明,当半焦粒度固定不变时,随着气煤的粒度增大,型焦的抗压强度增加,气煤粒度在0.5-0.9 mm之间,型焦的抗压强度出现峰值;之后,随着气煤粒度的进一步增大,型焦的抗压强度逐渐降低;当气煤粒度固定不变时,随着半焦粒度的增加,型焦抗压强度急剧减少.焦炭样品的光学显微组分中以各向同性为主,气煤和弱粘煤半焦的粒度对显微组分的影响很小.

关键词：气煤弱粘煤半焦粒度型焦抗压强度

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红外焦平面阵列测试的任意数据发生器

核电子学与探测技术 2007年第4期27卷 697-700页

作者：郑裕峰王永纲中国科学技术大学近代物理系合肥230026

介绍一个用于红外焦平面阵列（IrFPA）测试系统的任意数据发生器，说明它的工作原理和整体实现结构。任意数据发生器能产生16路最长是32×2^20个FPGA内部时钟周期的同步任意数字波形信号，内部时钟周期从20-1310700ns内可调，各路信号... 详细信息

介绍一个用于红外焦平面阵列（IrFPA）测试系统的任意数据发生器，说明它的工作原理和整体实现结构。任意数据发生器能产生16路最长是32×2^20个FPGA内部时钟周期的同步任意数字波形信号，内部时钟周期从20-1310700ns内可调，各路信号间的相对延迟的微调范围是0-127.5ns，微调步长是0.5ns。任意数据发生器包括一块VXI总线插卡和控制软件两部分，用户通过软件界面编辑并产生任意数字波形。

关键词：红外焦平面阵列任意数据发生器 Vxl FPGA 延迟线

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损耗对表面等离子体激元压缩态的影响

物理学报 2011年第2期60卷 260-263页

作者：李巍王永钢杨伯君北京邮电大学理学院北京100876

表面等离子体激元是金属表面电子集体振荡,它以波的形式在金属和介质之间的界面中传播.近期Huck等证明等离子体激元可以处在压缩态,本文利用量子光学的热库理论,研究金波导损耗对表面等离子体激元压缩态的影响,并对Huck等的实验结果给... 详细信息

表面等离子体激元是金属表面电子集体振荡,它以波的形式在金属和介质之间的界面中传播.近期Huck等证明等离子体激元可以处在压缩态,本文利用量子光学的热库理论,研究金波导损耗对表面等离子体激元压缩态的影响,并对Huck等的实验结果给与理论解释.

关键词：表面等离子体激元压缩态热库理论

How interfacial electron-donating defects influence the structure and charge of gold nanoparticles on TiO_(2)support

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Nano Research 2024年第7期17卷 5965-5974页

作者： Guang-Jie Xia Yu Fu Wei Cao Jun Li Yang-gang wang Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and TechnologyShenzhen 518055China School of Physical Sciences Great Bay UniversityDongguan 523000China Department of Chemistry Tsinghua UniversityBeijing 100084China

The reduction degree of TiO_(2)support is critical to the performances of metal *** many previous theoretical calculations,only the bridge oxygen vacancy(Ov)was considered as the electron-donating defect on reduced rutile TiO_(2)(r-TiO_(2−x))***,titanium adatoms(Tiad.),oxidized titanium islands(***),and acid hydroxyls(ObrH)also exist at the metal/support *** conducting density functional theory(DFT)calculations and ab initio molecular dynamics(AIMD)simulations,we compared r-TiO_(2−x)surfaces with Ov,Tiad.,***,and ObrH sites loaded with Au nanoparticles(NPs).The results showed the Au NPs were oxygen-phobic but titanium-philic,resulting in wetting of Ov and *** short contact with *** and *** Bader charges of Au NPs(QM)showed a good linear relationship with the ideal number of donating electrons(Ne)from the defective sites(QM=−KeNe+QM,S),demonstrating the intrinsic electron allocation at the *** Ov,Tiad.,and *** exhibited similar slopes(Ke),relatively steeper than that of *** means in the scope of Au NP charge state,the *** *** have a close electron-donating ability with Ov,but the ObrH donates relatively fewer *** linear relationship can be extended approximately to other *** higher the metal work function,the steeper the Ke for easier electron donation from defective *** stronger the metal oxygen affinity,the more positive the intercept(QM,S).That explains the easy generation of metallic or negative Pt and Au NPs on r-TiO_(2−x),but hard for Cu and Zn in *** provides theoretical guidance for regulating the charge of metal NPs over TiO_(2−x)supports.

关键词： metal-support interaction titanium oxide oxygen vacancy surface hydroxyl titanium adatom

Synthesis of porous flower-like SnO_(2)/CdSnO_(3) microstructures with excellent sensing performances for volatile organic compounds

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Frontiers of Materials Science 2024年第1期18卷 45-57页

作者： Jie Wan gang wang Haibo Ren Jiarui Huang Sang Woo Joo School of Materials Science and Engineering Anhui Polytechnic UniversityWuhu 241000China Key Laboratory of Functional Molecular Solids of the Ministry of Education College of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002China School of Mechanical Engineering Yeungnam UniversityGyeongsanGyeoungbuk 712749Republic of Korea

Porous flower-like SnO_(2)/CdSnO_(3) microstructures self-assembled by uniform nanosheets were synthesized using a hydrothermal process followed by calcination,and the sensing performance was measured when a gas sensor,based on such microstructures,was exposed to various volatile organic compound(VOC)*** response value was found to reach as high as 100.1 when the SnO_(2)/CdSnO_(3) sensor was used to detect 100 ppm formaldehyde gas,much larger than those of other tested VOC gases,indicating the high gas sensitivity possessed by this sensor especially in the detection of formaldehyde ***,the response/recovery process was fast with the response time and recovery time of only 13 and 21 s,*** excellent gas sensing performance derive from the advantages of SnO_(2)/CdSnO_(3),such as abundant n-n heterojunctions built at the interface,high available specific surface area,abundant porosity,large pore size,and rich reactive oxygen species,as well as joint effects arising from SnO_(2) and CdSnO_(3),suggesting that such porous flower-like SnO_(2)/CdSnO_(3) microstructures composed of nanosheets have a high potential for developing gas sensors.

关键词： SnO_(2)/CdSnO_(3) porous flower-like microstructure volatile organic gas sensingproperty gas sensor

冲击加载下20钢中弹性前驱波衰减与应力松弛行为实验研究

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高压物理学报 2007年第1期21卷 35-39页

作者：王永刚贺红亮中国工程物理研究院流体物理研究所冲击波物理与爆轰物理实验室

通过改变样品厚度,对平面冲击加载下20钢的弹性前驱波的波幅衰减和应力松弛进行了实验研究。采用激光速度干涉测速仪(VISAR)实测了样品后自由面速度历史,采样频率达到1 ns,保证了实验结果的准确性。实验结果显示:Hugoniot弹性极限随着... 详细信息

通过改变样品厚度,对平面冲击加载下20钢的弹性前驱波的波幅衰减和应力松弛进行了实验研究。采用激光速度干涉测速仪(VISAR)实测了样品后自由面速度历史,采样频率达到1 ns,保证了实验结果的准确性。实验结果显示:Hugoniot弹性极限随着传播距离呈指数衰减,在所研究的样品厚度范围内,Hugoniot弹性极限减小了44%;应力松弛行为和弹性前驱波的上升沿时间也依赖于传播距离;冲击加载的强度对材料动态屈服行为的影响很小。

关键词：固体力学弹性前驱波应力松弛 20钢

Electrostatically connected nanoarchitected electrocatalytic films for boosted water splitting

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Nano Research 2024年第3期17卷 1114-1122页

作者： Chao-Peng wang Hao Sun gang Bian Jia-Xi wang Xixi Pang Guoqi wang Jian Zhu Xian-He Bu School of Materials Science and Engineering National Institute for Advanced MaterialsNankai UniversityTianjin 300350China Tianjin Key Laboratory of Metal and Molecule-Based Material Chemistry Nankai UniversityTianjin 300350China Tianjin Key Laboratory for Rare Earth Materials and Applications Nankai UniversityTianjin 300350China

Active sites of two-dimensional(2D)electrocatalysts are often partially blocked owing to their inevitable stacking and hydrophobic polymeric binders in macroscale electrodes,therefore impeding their applications in efficient ***,using layered double hydroxide(LDH)nanosheets as a model 2D electrocatalyst,we demonstrate that their performance toward water splitting can be boosted when they are electrostatically assembled into an organized structure pillared by hydrophilic polyelectrolytes or nanoparticles in a layer-by-layer(LbL)*** particular,their mass activity on a planar electrode can be as large as 2.267 mA·μg^(-1) toward oxygen evolution reaction(OER),when NiFe-LDH nanosheets are electrostatically connected by poly(sodium 4-styrenesulfonate)(PSS),while drop-casted NiFe-LDH nanosheets only have a mass activity of 0.116 mA·μg^(-1).In addition,these homogeneous NiFe-LDH nanofilms can be easily deposited on three-dimensional(3D)surfaces with high areas,such as carbon cloths,to serve as practical electrodes with overpotentials of 328 mV at a current density of 100 mA·cm^(-2),and stability for 40 ***,Pt nanoparticles can be LbL assembled with NiFe-LDH as bifunctional electrodes for synergistically boosted oxygen and hydrogen evolution reactions(HER),leading to successful overall water splitting powered by a 1.5 V *** study heralds the spatial control of 2D nanomaterials in nanoscale precision as an efficient strategy for the design of advanced electrocatalysts.

关键词： layer-by-layer(LbL)assembly layered double hydroxides(LDH) two-dimensional(2D)electrocatalysts oxygen evolution reaction(OER) water splitting

Laser-Constructing 3D Copper Current Collector with Crystalline Orientation Selectivity for Stable Lithium Metal Batteries

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Energy & Environmental Materials 2024年第6期7卷 129-139页

作者： Hui Li gang wang Jin Hu Jun Li Jiaxu Huang Shaolin Xu Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518000China

The practical application of lithium(Li)metal anodes in high-capacity batteries is impeded by the formation of hazardous Li *** address this challenge,this research presents a novel methodology that combines laser ablation and heat treatment to precisely induce controlled grain growth within laser-structured grooves on copper(Cu)current ***,this approach enhances the prevalence of Cu(100)facets within the grooves,effectively lowering the overpotential for Li nucleation and promoting preferential Li *** approaches that modify the entire surface of collectors,our work focuses on selectively enhancing lithiophilicity within the grooves to mitigate the formation of Li dendrites and exhibit exceptional performance *** half-cell with these collectors maintains a remarkable Coulombic efficiency of 97.42%over 350 cycles at 1 mA cm^(−2).The symmetric cell can cycle stably for 1600 h at 0.5 mA cm^(−2).Furthermore,when integrated with LiFePO4 cathodes,the full-cell configuration demonstrates outstanding capacity retention of 92.39%after 400 cycles at a 1C discharge *** study introduces a novel technique for fabricating selective lithiophilic three-dimensional(3D)Cu current collectors,thereby enhancing the performance of Li metal *** insights gained from this approach hold promise for enhancing the performance of all laser-processed 3D Cu current collectors by enabling precise lithiophilic modifications within complex structures.

关键词： copper current collector heat treatment laser processing lithium metal battery selective crystalline orientation