检索结果-南通市图书馆

Sustainable propane dehydrogenation reaction triggered by strong metal-support interaction

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2024年

作者： Lichen liu Avelino Corma Engineering Research Center of Advanced Rare Earth Materials Department of Chemistry Tsinghua University Instituto de Tecnología Química Universitat Politécnica de València-Consejo Superior de Investigaciones Científicas (UPV-CSIC)

This Highlight is inspired by a recent article in Science in which Gong and co-workers from Tianjin University reported a discovery of defective TiOxoverlayers on metallic Ni nanoparticles induced by strong metal-support interaction and their applications in propane dehydrogenation reaction[1]. This work represents a conceptual innovation in the design of sustainable catalysts with state-of-the-art efficiency for alkane dehydrogenation reactions based on ecofriendly metal oxides and non-noble metals.

关键词：

Coupling Co2P nanoparticles onto N,P-doped biomass-derived carbon as efficient electrocatalysts for flexible Zn–air batteries

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第10期43卷 4982-4991页

作者： Shu-Qi Li Kang Sun Yan-Yan liu Shu-Ling liu Jing-Jing Zhou Wen-Bo Zhang Yi-Hang Lu Xiang-Meng Chen Xiao-Peng Wang Bao-Jun Li Jian-Chun Jiang College of Science Henan Agricultural University Department of Chemistry Tsinghua University College of Chemistry Zhengzhou University Institute of Chemical Industry of Forest Products National Engineering Lab for Biomass Chemical UtilizationKey and Open Lab on Forest Chemical EngineeringChinese Academy of ForestryState Forestry Administration

Catalysts for oxygen conversion play an important role in energy storage and conversion technologies such as metal-air *** highly active stable,and low-cost catalysts is critical for further implementation of the above ***,an efficien oxygen electrocatalyst with Co2P nanoparticles （NPs）coupling onto N,P-doped porous carbon nanosheets（Co2P@NPAC） derived from cotton stalk is successfully designed and prepared via activation,hydrothermal treatment,and pyrolysis *** excellent properties of electrical conductivity,mass transfer,and synergistic integration between Co2P and N,P-doped carbon endow Co2P@NPAC composite with superior oxygen reduction reaction/oxygen evolution reaction （ORR/OER） ***2P@NPAC catalyst achieves ORR activity with half-wave potential of 0.85 V and high OER activity with overpotential of 261 mV at 10 mA·*** flexible Zn-air batteries （ZABs） based on Co2P@NPAC catalyst revea outstanding performances with a high open-circuit voltage（1.38 V）,a peak power density of (75 mW·cm-2),and a low charge-discharge voltage gap （0.74 V,～200 cycles）The flexible ZABs express the stable discharge-charge voltage gap at various bending *** work provides interesting inspiration for the ingenious design of efficien carbon electrocatalysts from biomass with potential application of energy storage and conversion devices.

关键词： Cotton stalk Flexible Zn–air batteries N,P-doped activated carbon Oxygen reduction reaction

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

磷酸镁水泥基帆布力学与微观性能研究

材料导报 2024年第17期38卷 7-12页

作者：刘雄飞王楠郝逸飞李辉河北工业大学土木与交通学院天津300401 建筑3D打印河北省工程研究中心天津300401

基于磷酸镁水泥(MPC)快硬早强和高粘结特性,研发了应急防护型MPC帆布。研究了不同镁磷物质的量比(M/P=3~8)和水灰比(W/C=0.15~0.5)对MPC帆布抗压和抗弯强度的影响规律,并结合XRD、SEM和X-CT分析MPC在帆布中的水化反应形貌、产物和孔结... 详细信息

基于磷酸镁水泥(MPC)快硬早强和高粘结特性,研发了应急防护型MPC帆布。研究了不同镁磷物质的量比(M/P=3~8)和水灰比(W/C=0.15~0.5)对MPC帆布抗压和抗弯强度的影响规律,并结合XRD、SEM和X-CT分析MPC在帆布中的水化反应形貌、产物和孔结构变化规律,提出MPC帆布优化设计方法。实验结果表明:M/P显著影响MPC帆布的力学性能,M/P为6时,MPC帆布在28 d龄期的抗压和抗弯强度分别达到最佳值26.65 MPa和6.20 MPa。W/C决定MPC在帆布中的水化程度,低或过高的W/C均无法保证MPC在帆布中的整体性,MPC帆布的最佳W/C为0.35,在该条件下,MPC帆布在28 d龄期的抗压和抗弯强度分别达到最高值26.90 MPa和6.30 MPa,MPC水化产物(K-鸟粪石)最多且MPC与帆布纤维界面粘结密实,孔隙率最小(7.63%),MPC帆布整体性达到最佳。

关键词：混凝土帆布磷酸镁水泥力学性能水化过程

深水导管架平台波浪动力响应及参数敏感性分析

在线全文

学校读者我要写书评

暂无评论

船海工程 2024年第1期53卷 127-131页

作者：柴俊凯徐辉刘圆中国船级社海洋工程技术中心天津300457

考虑到300 m级导管架平台的自振周期与自升式平台极为接近,自升式平台的波浪动力响应分析方法在理论上可应用于深水导管架平台,但应用前需要进行参数敏感性分析,采用SACS软件建立300 m级导管架平台有限元模型,结合JONSWAP波浪谱、利用... 详细信息

考虑到300 m级导管架平台的自振周期与自升式平台极为接近,自升式平台的波浪动力响应分析方法在理论上可应用于深水导管架平台,但应用前需要进行参数敏感性分析,采用SACS软件建立300 m级导管架平台有限元模型,结合JONSWAP波浪谱、利用线性叠加法构造满足高斯性条件的随机波浪;基于时域分析法,进行在随机波浪载荷下的结构动力响应分析;采用Winterstein/Jensen方法计算平台基底剪力和倾覆力矩的最可能最大值,以及动力放大系数;对波浪瞬态变化、模拟步长和时长、随机种子等参数对动力放大系数进行敏感性分析,结果表明,动力放大系数对波浪瞬态变化较为敏感、对模拟步长和时长,以及随机种子极为敏感。采用Winterstein/Jensen方法进行深水导管架平台动力响应分析时,基于敏感性分析得出的参数可获得更合理、准确的动力放大系数。

关键词：深水导管架平台 Winterstein/Jensen方法最可能最大值动力放大系数时域分析方法敏感性分析

Designed imidazole-based supramolecular catalysts for accelerating oxidation/hydrolysis cascade reactions

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第6期17卷 4916-4923页

作者： Yuanxi liu Wenjie Xu Shichao Xu Haifeng Wu Baoli Zhang Li Song Zhen-Gang Wang State Key Laboratory of Organic-Inorganic Composites Key Lab of Biomedical Materials of Natural Macromolecules(Ministry of Education)Beijing Laboratory of Biomedical MaterialsCollege of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China National Synchrotron Radiation Laboratory CAS Center for Excellence in NanoscienceUniversity of Science and Technology of ChinaHefei 230029China

Reconstructing enzymatic active sites presents a significant challenge due to the intricacies involved in achieving enzyme-like scaffold folding and spatial arrangement of essential functional *** is also a growing interest in building biocatalytic networks,wherein multiple enzymatic active sites are localized within a single artificial system,allowing for cascaded *** this work,we report the self-assembly of imidazole or its derivatives with fluorenylmethyloxycarbonyl-modified histidine and Cu2+to fabricate a supramolecular catalyst,which possesses catechol oxidase-like dicopper center with multiple imidazole as the coordination *** electron microscopy,low-temperature X-band continuous-wave electron paramagnetic resonance,K-edge X-ray absorption spectra/the extended X-ray absorption fine structure analysis,and density functional theory modeling were used for the structural characterization of the *** phenol derivatives and the dissolved oxygen were used as the substrates,with the addition of 4-aminoantipyrine to generate a red adduct with a maximum absorbance at 510 nm,for obtaining time-dependent absorbance change curves and estimating the *** results reveal that the addition of imidazole synergistically accelerates the oxidative activity about 10-fold and the hydrolysis activity about 14-fold than fluorenylmethyloxycarbonyl modified-histidine/Cu2+.The supramolecular nanoassembly also exhibits the ability to catalyze oxidation/hydrolysis cascade reactions,converting 2′,7′-dichlorofluorescin diacetate into 2′,7′-*** process can be regulated through the methylation of the imidazole component at various *** work may contribute to the design of advanced biomimetic catalysts,and shed light on early structural models of the active sites of the primitive copper-dependent enzymes.

关键词： enzyme mimic self-assembly supramolecular catalyst cascade reactions

Temporally consistent video colorization with deep feature propagation and self-regularization learning

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computational Visual Media 2024年第2期10卷 375-395页

作者： Yihao liu Hengyuan Zhao Kelvin CKChan Xintao Wang Chen Change Loy Yu Qiao Chao Dong Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China University of Chinese Academy of Sciences Beijing 100049China Department of Electrical&Computer Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798 Applied Research Center Tencent PCGShenzhenChina

Video colorization is a challenging and highly ill-posed *** recent years have witnessed remarkable progress in single image colorization,there is relatively less research effort on video colorization,and existing methods always suffer from severe flickering artifacts(temporal inconsistency)or unsatisfactory *** address this problem from a new perspective,by jointly considering colorization and temporal consistency in a unified ***,we propose a novel temporally consistent video colorization(TCVC)*** effectively propagates frame-level deep features in a bidirectional way to enhance the temporal consistency of ***,TCVC introduces a self-regularization learning(SRL)scheme to minimize the differences in predictions obtained using different time *** does not require any ground-truth color videos for training and can further improve temporal *** demonstrate that our method can not only provide visually pleasing colorized video,but also with clearly better temporal consistency than state-of-the-art methods.A video demo is provided at https://***/watch?v=c7dczMs-olE,while code is available at https://***/lyh-18/TCVC-Tem porally-Consistent-Video-Colorization.

关键词： video colorization temporal consistency feature propagation self-regularization

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

高钠血症的诊断和治疗

中国实用内科杂志 2024年第5期44卷 361-364页

作者：刘志红张力辉河北医科大学第二医院内分泌科河北石家庄050000

高钠血症是一种常见的电解质紊乱,尤其在婴幼儿、老年人和危重症患者中发生率和病死率较高。血清钠浓度与水稳态有关,水稳态依赖于下丘脑渴觉中枢、精氨酸加压素和肾脏对精氨酸加压素的反应调节,文章介绍了高钠血症的主要发病机制,为高... 详细信息

高钠血症是一种常见的电解质紊乱,尤其在婴幼儿、老年人和危重症患者中发生率和病死率较高。血清钠浓度与水稳态有关,水稳态依赖于下丘脑渴觉中枢、精氨酸加压素和肾脏对精氨酸加压素的反应调节,文章介绍了高钠血症的主要发病机制,为高钠血症患者提供了具体的治疗方向。由于高钠血症的纠正率和病死率显著相关,因此及时有效地治疗至关重要。高钠血症可分为三大类,低血容量性、等容量性和高血容量性,每种类型都有独特的治疗需求。

关键词：高钠血症诊断治疗

FLUID CHARACTERISTICS OF ROTARY WING HEAT METER WITH SINGLE-CHANNEL

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2008年第1期20卷 101-107页

作者： Du guang-sheng liu Zheng-gang LI Li liu Yong-hui MA Yong-kun MENG Liang School of Energy and Power Engineering Shandong University Jinan 250061China

Fluid characteristics of a rotary wing heat meter with single-channel were studied through theretical analysis, numerical simulation and experiments. The obtained results show that the number of vanes can obviously influence the heat meter, but the water temperature seldom influence the meter , and the optimal number of vane is 6-8.

关键词： heat meter numerical simulation meter

在线全文

学校读者我要写书评

暂无评论

高温热刺激下HMX基PBX炸药性能研究

火工品 2024年第2期 65-69页

作者：杨佳荟薛志华刘意赵宇光张中泽武碧栋中北大学环境与安全工程学院山西太原030051 辽宁北方华丰特种化工有限公司辽宁抚顺113003 山西省超细粉体工程技术研究中心山西太原030051

为了探究高温热刺激对HMX基PBX炸药性能的影响,采用HMX及氟橡胶(F2604)制备了HMX-F2604微球,将微球置于高温烘箱内,分别在160℃和200℃下加热1,4,8,12 h,对高温热刺激前后微球的质量损失率、形貌、流散性、堆积密度、热性能、机械感度... 详细信息

为了探究高温热刺激对HMX基PBX炸药性能的影响,采用HMX及氟橡胶(F2604)制备了HMX-F2604微球,将微球置于高温烘箱内,分别在160℃和200℃下加热1,4,8,12 h,对高温热刺激前后微球的质量损失率、形貌、流散性、堆积密度、热性能、机械感度和燃烧性能进行了测试。结果表明:在160℃下加热1~12 h的样品各项性能均未发生明显变化;在200℃下,加热1 h的样品性能未发生明显变化;加热4 h的样品性能变化较小;加热8 h和12 h的样品性能遭到严重破坏。

关键词： HMX 耐热性超高温热性能