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Building Simulation 2024年第2期17卷 207-221页

作者： xing hu huibo Zhang hui Yu School of Design Shanghai Jiao Tong UniversityShanghai200240China

Wind-driven rain(WDR)has a significant influence on the hygrothermal performance,durability,and energy consumption of building *** calculation of WDR loads using semi-empirical models has been incorporated into the boundary conditions of coupled heat and moisture transfer ***,prior research often relied on fixed WDR absorption ratio,which fail to accurately capture the water absorption characteristics of porous building materials under rainfall ***,this study aims to investigate the coupled heat and moisture transfer of exterior walls under dynamic WDR boundary conditions,utilizing an empirically obtained WDR absorption ratio model based on field *** developed coupled heat and moisture transfer model is validated against the HAMSTAD *** findings reveal that the total WDR flux calculated with the dynamic WDR boundary is lower than that obtained with the fixed WDR boundary,with greater disparities observed in orientations experiencing higher WDR *** variations in moisture flow significantly impact the surface temperature and relative humidity of the walls,influencing the calculation of cooling and heating loads by different *** to the transient heat transfer model,the coupled heat and moisture transfer model incorporating dynamic WDR boundary exhibits maximum increases of 17.6%and 16.2%in cooling and heating loads,*** dynamic WDR boundary conditions provide more precise numerical values for surface moisture flux,offering valuable insights for the thermal design of building enclosures and load calculations for HVAC systems.

关键词： wind-driven rain building component hygrothermal model transient simulation cooling and heating loads

Construction of Pd-doped RuO_(2) nanosheets for efficient and stable acidic water oxidation

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Green Energy & Environment 2024年第6期9卷 937-948页

作者： Yibo Liu xing hu Chenxi Liu Shan Zhu Kezhu Jiang Feng Liu Shijian Zheng Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology College of Materials Science and EngineeringHebei University of TechnologyTianjin300401China Yunnan Precious Metals Lab Co. LTDKunming650100China

RuO_(2) has been considered a potential alternative to commercial IrO_(2) for the oxygen evolution reaction(OER)due to its superior intrinsic ***,its inherent structure dissolution in acidic environments restricts its commercial *** this study,we report a novel Pd-doped ruthenium oxide(Pd–RuO_(2))nanosheet catalyst that exhibits improved activity and stability through a synergistic effect of Pd modulation of Ru electronic structure and the two-dimensional *** catalyst exhibits excellent performance,achieving an overpotential of only 204 mVat a current density of 10 mA cm^(-2).Impressively,after undergoing 8000 cycles of cyclic voltammetry testing,the overpotential merely decreased by 5 *** PEM electrolyzer with Pd0.08Ru0.92O_(2) as an anode catalyst survived an almost 130 h operation at 200 mA cm^(-2).To elucidate the underlying mechanisms responsible for the enhanced stability,we conducted an X-ray photoelectron spectroscopy(XPS)analysis,which reveals that the electron transfer from Pd to Ru effectively circumvents the over-oxidation of Ru,thus playing a crucial role in enhancing the catalyst's ***,density functional theory(DFT)calculations provide compelling evidence that the introduction of Pd into RuO_(2) effectively modulates electron correlations and facilitates the electron transfer from Pd to Ru,thereby preventing the overoxidation of ***,the application of the two-dimensional structure effectively inhibited the aggregation and growth of nanoparticles,further bolstering the structural integrity of the catalyst.

关键词： Oxygen evolution reaction Pd-doped ruthenium oxide Two-dimensional structure Electron transfer Stability

Cambricon-QR:a sparse and bitwise reproducible quantized training accelerator

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High Technology Letters 2024年第1期30卷 52-60页

作者：李楠 ZHAO Yongwei ZHI Tian LIU Chang DU Zidong hu xing LI Wei ZHANG Xishan LI Ling SUN Guangzhong School of Computer Science and Technology University of Science and Technology of ChinaHefei 230026P.R.China State Key Laboratory of Processors Institute of Computing TechnologyChinese Academy of SciencesBeijing 100086P.R.China Cambricon Tech.Ltd Beijing 100191P.R.China Institute of Software Chinese Academy of SciencesBeijing 100086P.R.China

Quantized training has been proven to be a prominent method to achieve deep neural network training under limited computational *** uses low bit-width arithmetics with a proper scaling factor to achieve negligible accuracy ***-Q is the ASIC design proposed to efficiently support quantized training,and achieves significant performance ***,there are still two caveats in the ***,Cambricon-Q with different hardware specifications may lead to different numerical errors,resulting in non-reproducible behaviors which may become a major concern in critical ***,Cambricon-Q cannot leverage data sparsity,where considerable cycles could still be squeezed *** address the caveats,the acceleration core of Cambricon-Q is redesigned to support fine-grained irregular data *** new design not only enables acceleration on sparse data,but also enables performing local dynamic quantization by contiguous value ranges(which is hardware independent),instead of contiguous addresses(which is dependent on hardware factors).Experimental results show that the accuracy loss of the method still keeps negligible,and the accelerator achieves 1.61×performance improvement over Cambricon-Q,with about 10%energy increase.

关键词： quantized training sparse accelerator Cambricon-QR

Five quinolizidine alkaloids with anti-tobacco mosaic virus activities from two species of Sophora

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Chinese Chemical Letters 2024年第6期35卷 380-384页

作者： Ji Zhang Tong Zhang Qiao An Peng Zhang Cai-Yan Tian Chun-Mao Yuan Ping Yi Zhan-xing hu Xiao-Jiang Hao State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical UniversityGuiyang 550014China Natural Products Research Center of Guizhou Province Guiyang 550014China School of Pharmaceutical Sciences Guizhou Medical UniversityGuiyang 550025China School of Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of ScienceKunming 650201China Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical SciencesKunming 650201China

Three novel matrine-type alkaloids(1-3)and two unprecedented aloperine-type alkaloids(4 and 5)were isolated from the root of Sophora tonkinensis and the seeds of Sophora alopecuroides ***,compound 1 possessed an unprecedented 6/5/6 tricyclic skeleton,while compounds 2 and 3 characterized by rare 6/6/5/6 tetracyclic system and 6/6/6/6/6 pentacyclic system ***,compound 4 possessed an unprecedented 6/7/6/6 tetracyclic core,and compound 5 characterized by rare 6/6/6/6tetracyclic *** structures were elucidated by comprehensive spectroscopic data analysis and electronic circular dichroism(ECD)*** tests indicated that compound 5 displayed significant anti-tobacco mosaic virus(TMV)activity compared with the positive control ningnanmycin.

关键词： Matrine-type alkaloids Aloperine-type alkaloids Sophora tonkinensis Sophora alopecuroides Anti-tobacco mosaic virus

Some Modified Equations of the Sine-Hilbert Type

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Chinese Physics Letters 2024年第4期41卷 1-6页

作者：闫铃娟刘亚杰胡星标 LSEC ICMSECAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

Three modified sine-Hilbert(sH)-type equations, i.e., the modified sH equation, the modified damped sH equation, and the modified nonlinear dissipative system, are proposed, and their bilinear forms are *** on these b... 详细信息

关键词： bilinear equations equation

Identifying the origin of porous evolution of microsized bismuth in potassium-ion batteries

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Science China Chemistry 2024年第7期67卷 2234-2239页

作者： Shenxu Chu Kaixiang Lei Qian Yang Jiaxin Li Yuqing Zhao Mengjia Gu Lin Li xing hu Yu Zhang Zhuo Chen Shuo Shi Shulei Chou Shijian Zheng Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology School of Materials Science and EngineeringHebei University of TechnologyTianjin 300401China Institute for Carbon Neutralization Technology College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China

Microsized bismuth(Bi)with in-situ constructed three-dimensional(3D)porous network has been considered as a promising anode for high-performance potassium-ion batteries(PIBs).However,the mechanism of the in-situ porous evolution of microsized Bi during the charge/discharge process is still ***,various electrolytes are employed to disclose the origin of porous evolution of microsized Bi in *** and theoretically,the 3D porous network originates from the uniform interfacial charge distribution on the Bi surface in the linear ether-based *** addition,the universality of the interfacial charge distribution mechanism was verified by microsized Sn and *** in-situ constructed 3D porous network of Bi enables a superior potassium storage performance in a wide temperature range from-40 to 40℃.More importantly,the K_(0.9)Mn_(0.7)Ni_(0.3)O_(2)||Bi full cell delivers excellent cycling stability(a high capacity retention of 88.44%even after 2,000 cycles)and good temperature *** work gives a distinct clarification of the origin of the porous evolution of microsized Bi during cycling,which is critical for developing high-performance PIBs.

关键词： potassium-ion batteries microsized Bi porous evolution linear ether-based electrolyte interfacial charge distribution

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三峡工程蓄水运用20年综合效益发挥与展望

长江科学院院报 2024年第6期41卷 1-9页

作者：胡兴娥曹瑞中国长江三峡集团有限公司流域枢纽运行管理中心湖北宜昌443133 中国长江三峡集团有限公司高坝大库运行安全湖北省重点实验室湖北宜昌443133

三峡工程自2003年蓄水发电至今已运行20 a,初步设计主要功能全部实现,并适应运行条件变化和发展需求持续优化运行方式,防洪、发电、航运、水资源利用等综合效益全面发挥。截至2023年底,三峡工程累计拦洪运用66次,拦蓄洪水超2 088亿m^(3)... 详细信息

三峡工程自2003年蓄水发电至今已运行20 a,初步设计主要功能全部实现,并适应运行条件变化和发展需求持续优化运行方式,防洪、发电、航运、水资源利用等综合效益全面发挥。截至2023年底,三峡工程累计拦洪运用66次,拦蓄洪水超2 088亿m^(3),确保了荆江河段防洪安全,极大减轻了长江中下游防洪压力;累计发出清洁电能超16 600亿kW·h,相当于节约标准煤5.1亿t,减少二氧化碳排放13.3亿t;极大改善了库区与长江中游航道条件,累计通过货运量超20亿t,有力促进了长江航运快速发展;枯水期累计向下游补水约3 400亿m^(3),有效保障了长江中下游供水安全;生态调度成效显著,四大家鱼资源量明显恢复。为了应对频发的极端水文事件带来的风险和挑战,确保三峡工程长期安全运行和持续发挥巨大综合效益,从推进气象水文预报技术研究与应用、三峡水库调度运行方案优化、创新成果转化运用、智慧化管理等方面提出了下一步工作展望。

关键词：三峡工程综合效益防洪发电航运水资源利用

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城市设计之魅:“乱糟糟”的日常

建筑师 2024年第3期 25-30页

作者：胡兴华中科技大学建筑与城市规划学院自然资源部城市仿真重点实验室

通过将魅惑不清、高度混杂的日常生活,视为城市设计中难以被理性化的处理对象,本文分别从认识论与方法论上讨论了设计师应该如何理解并拥抱这种日常之魅。

关键词：日常生活城市设计祛魅

大气湍流对空间相干光通信的相干探测性能影响

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物理学报 2024年第10期73卷 203-211页

作者：刘宇韬徐苗付兴虎付广伟燕山大学信息科学与工程学院河北省特种光纤与光纤传感重点实验室秦皇岛066004 自然资源部海洋观测技术重点实验室天津300112

空间相干光通信被认为是突破现有高速空间通信瓶颈的重要手段,但其应用受到大气湍流的极大限制.为此,本文首先基于huygens-Fresnel原理和低频补偿功率谱反演法,研究了高斯光束经大气湍流传输后振幅和相位的随机分布特性;然后,利用相干... 详细信息

空间相干光通信被认为是突破现有高速空间通信瓶颈的重要手段,但其应用受到大气湍流的极大限制.为此,本文首先基于huygens-Fresnel原理和低频补偿功率谱反演法,研究了高斯光束经大气湍流传输后振幅和相位的随机分布特性;然后,利用相干混频效率及通信误码率模型,获得大气湍流对空间相干光通信系统性能的影响规律;最后,搭建激光外差探测实验系统,定量研究了大气湍流对空间相干光通信相干探测性能的影响.结果表明:弱湍流条件下,空间相干光通信性能几乎不受大气湍流的影响;中等强度湍流影响下,相干混频效率会随着湍流强度的增大而迅速下降,但通过提高单比特光子数可以有效抑制湍流对通信性能的负面影响;强湍流会显著破坏光束相干性,使得相干混频效率趋近于零,即使提高单比特光子数也无法有效改善通信性能.大气湍流是空间相干光通信发展的重要限制因素,该研究可为空间相干光通信系统性能评估提供有益参考.

关键词：空间相干光通信大气湍流混频效率误码率

不同增温模式对西南亚高山针叶林云杉养分及其化学计量特征的影响

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应用与环境生物学报 2024年第1期30卷 83-89页

作者：胡星刘庆赵春章李丹丹成都理工大学生态环境学院成都610059 中国科学院成都生物研究所成都610213

由于昼、夜增温速率的不对称性,植物对白天与夜间温度变化的响应呈现差异,研究西南亚高山针叶树种粗枝云杉(Picea asperata)各级根系和叶片的养分(C、N、P、K、Ca、Mg)及其化学计量特征对昼、夜增温的响应差异,有助于加深气候变暖对高... 详细信息

由于昼、夜增温速率的不对称性,植物对白天与夜间温度变化的响应呈现差异,研究西南亚高山针叶树种粗枝云杉(Picea asperata)各级根系和叶片的养分(C、N、P、K、Ca、Mg)及其化学计量特征对昼、夜增温的响应差异,有助于加深气候变暖对高海拔地区植物影响机制的理解.采用红外辐射加热对云杉幼苗分别进行白天和夜间增温,同时设置对照.结果表明:(1)云杉根系形态结构和养分含量呈现模块化特征,低级根(1-2级)的比根长、比表面积及N、K、Ca、Mg含量均显著大于高级根(3-5级),叶片C、N、P、K含量均显著大于根系;(2)昼、夜增温均显著增加了云杉叶片N、P、K、Mg含量(白天增幅分别为17.58%、66.12%、11.00%、18.31%;夜间增幅分别为37.12%、6.63%、29.50%、4.97%),但云杉根系的养分吸收与分配情况对两种增温模式的响应不同.白天增温显著增加了云杉各级根系C、N、P含量及高级根K含量(增幅分别为2.09%-2.69%、15.28%-69.87%、26.39%-86.26%、19.73%-32.28%),降低了各级根系Mg含量及低级根K含量(降幅分别为8.09%-19.68%、14.98%-27.73%);夜间增温显著增加了云杉各级根系N含量(增幅为9.70%-50.14%),降低了各级根系C、P、K、Mg含量(降幅分别为4.85%-17.88%、5.27%-29.92%、16.52%-25.56%、4.99%-16.92%);(3)云杉低级根与叶片C:N、C:P比值大于高级根,白天增温显著降低了各级根系与叶片的C:N、C:P比值;夜间增温显著降低了各级根系、叶片的C:N比值与低级根的C:P比值,增加了高级根的C:P比值,昼、夜增温在一定程度上缓解了氮磷限制情况.综上所述,昼、夜增温对云杉养分积累与分配影响呈现出差异,对植物生长的影响机制不同,在森林生态系统气候变暖研究中应该同时考虑白天、夜间增温的影响,进而准确预测气候变暖对高海拔地区植物的影响.(图3表2参51)

关键词：白天增温夜间增温根系分级养分化学计量特征

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