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IEC 62368-1《音视频、信息技术和通信技术设备第1部分:安全要求》第四版的主要技术更新解析

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中国标准化 2024年第2期 128-135页

作者：姚青梅高岭松徐永生赵羽声中家院(北京)检测认证有限公司北京泰瑞特检测技术服务有限责任公司

GB4943.1-2022《音视频、信息技术和通信技术设备第1部分:安全要求》修改采用了国际标准IEC62368-1:2018第三版,2023年5月国际电工委员会(IEC)发布了IEC 62368-1:2023 (第四版),在第三版的基础上进行了技术方法升级改进,澄清或替代了第... 详细信息

GB4943.1-2022《音视频、信息技术和通信技术设备第1部分:安全要求》修改采用了国际标准IEC62368-1:2018第三版,2023年5月国际电工委员会(IEC)发布了IEC 62368-1:2023 (第四版),在第三版的基础上进行了技术方法升级改进,澄清或替代了第三版中的一些要求。本文从结构和元器件要求、电能量源要求和着火方面等11个方面对这些更新的技术要求和测试方法进行解析,可看出第四版标准的适用性更强,顺应了当前技术产业发展趋势。

关键词：增加更新安全防护测试评估要求

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FULLY RESOLVED NUMERICAL SIMULATION OF TURBULENT PIPE FLOWS LADEN WITH LARGE NEUTRALLY-BUOYANT PARTICLES

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Journal of Hydrodynamics 2011年第1期23卷 21-25页

作者： WU Teng-hu SHAO Xue-ming yu zhao-sheng State Key Laboratory of Fluid Power Transmission and Control Department of Mechanics Zhejiang UniversityHangzhou 310027 China

In this article,we employ a fully-resolved numerical simulation method（the fictitious domain method）to investigate the effects of large neutrally-buoyant particles on the turbulent flow in a pipe at low Reynolds number and non-dilute *** tube Reynolds number is fixed to be 4 900,the particle-pipe diameter ratio is 0.1,and the particle volume fraction ranges from 0.33%to 10%.Our results indicate that the presence of large particles decreases the maximum root-of-mean-square（rms）of the streamwise velocity fluctuation near the wall by weakening the intensity of large-scale streamwise vortices,although in the region very close to the wall the particles increase the rms of streamwise velocity *** the other hand,the particles induce small-scale vortices in the near-wall region,resulting in the enhancement of the rms of radial and circumferential velocity fluctuations there.

关键词： fully-resolved direct numerical solution particulate turbulent pipe flow large particles particle-turbulence interactions

THREE-DIMENSIONAL PAIRING OF COHERENT STRUCTURES IN A PLANE MIXING LAYER

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Journal of Hydrodynamics 2002年第2期14卷 1-6页

作者： Lin, Jian-Zhong Shi, Xing yu, zhao-sheng Shao, Xue-Ming Dept. of Mech. Lab. of Fluid Power Trans. Zhejiang Univ. Hangzhou 310027 China

The three-dimensional (3D) pairing process of coherent structures in a plane mixing layer was simulated numerically with the pseudo-spectral method. The behaviors of spanwise cup-shaped vortices, streamwise rib-shaped vortices and quadrupoles were obtained in terms of their iso-surfaces. The results show that three-dimensional structures are strongly influenced by the initial amplitude of the 3D disturbance, and that in most cases the local pairing finishes in a roughly two-dimensional manner. In pairing region, the streamwise vortices are chaotic after pairing due to the breakdown of the engulfed ribs and especially the subsequent breakdown of the quadrupoles. The surviving ribs extend to the top (or bottom) of the paired vortices under the stretch of them. In addition, it is revealed that three dimensional vortices pairing can enhance the mixing of fluid. Finally, some patterns of numerical flow visualization are presented by computing the passive scalar.

关键词： Flow of fluids Flow visualization Mixing Numerical analysis Three dimensional

New model of linkage evolution for the transtensional fault systems in the Nanpu Sag of Bohai Bay Basin: Insight from seismic interpretation and analogue modelling

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Petroleum Science 2024年第4期21卷 2287-2310页

作者： yu-Heng Wang Fu-sheng yu Bao-Yin zhao Ling-Jian Meng College of Geosciences China University of Petroleum (Beijing) State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum (Beijing) Jidong Oilfield Company PetroChina Limited Company

The evolution of faults within the same stress field is frequently influenced by numerous factors,involving the reactivation of pre-existing structures, stress transmission through ductile detachment layers, and the growth, interaction, as well as linkage of new fault segments. This study analyses a complex multi-phase oblique extension fault system in the Nanpu Sag(NPS) of the Bohai Bay Basin(BBB),China. High-resolution three-dimensional(3D) seismic data and analogue modelling indicate that the oblique extensional reactivation of pre-existing structures governs the sequential arrangement of fault segments in the caprock, and they dip synthetically to the reactivated fault at depth. During the NW-SE extension in the Eocene, the predominant movement of the pre-existing fault is strike-slip. Subsequently,during the N-S extension since the Oligocene, inclined at *** the pre-existing fault, forming splay fault segments and ultimately creating large en-echelon arcuate faults linked by relay ramps. Using fault throw-distance(T-D) and laser scanning, we reconstructed the fault evolution model of oblique extension reactivation in the presence of a ductile detachment basement. Our study illustrates that the arcuate faults can be categorized into linear master fault segments controlled by pre-existing structures, bending splay faults in the termination zone, and normal fault segments responding to the regional stress *** interaction between faults occurs among normal faults and strike-slip faults, and the kinematic unification of the two fault systems is accomplished in the intersection zone. As the faults continue to evolve, the new fault segments tend to relinquish the control of pre-existing structures and concentrate more on the development of planar and continuous major faults. The ductile detachment layer significantly contributes to the uniform distribution of strain, resulting in narrow shear zones and discontinuous normal faults in its absence.

关键词： Analogue modelling Transtensional deformation Fault linkage Fault intersection zone Nanpu Sag of Bohai Bay basin

Non-Gaussian feature of the output field from a double qubit-cavity ultrastrong coupling system

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Communications in Theoretical Physics 2024年第7期76卷 30-36页

作者： sheng-wen Xu Shi-yu Dai Teng zhao Center for Quantum Science and Technology Jiangxi Normal UniversityNanchang 330022China

We investigate the non-Gaussian feature of radiation in a circuit quantum electrodynamics(QED)system where two qubits are strongly coupled to a single-mode *** the regime of ultrastrong coupling(USC),the rotating-wave approximation is not valid,and the Rabi Hamiltonian contains counter-rotating wave terms,leading to level crossing and avoided crossings in the energy *** further analyze the intensity-amplitude correlation of the output field in these two novel *** the USC regime,the creation and annihilation operators in the correlation function are replaced,allowing for the identification of non-Gaussian features in the output *** findings reveal that despite the absence of squeezing effects in the output light,significant non-Gaussian characteristics are ***,we demonstrate that as the driving or coupling strength increases,the non-Gaussian features of the output field become more *** suggests that USC systems hold broad potential applications in the realms of nonlinear optics and the generation of non-Gaussian states.

关键词： ultrastrong coupling non-Gaussian intensity-amplitude correlation

Fracture geometry and breakdown pressure of radial borehole fracturing in multiple layers

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Petroleum Science 2024年第1期21卷 430-444页

作者： yu-Ning Yong zhao-Quan Guo Shou-Ceng Tian Lu-Yao Ma Tian-yu Wang Mao sheng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China Beijing Petroleum Machinery Company Limited CNPC Engineering Technology R&D Company LimitedBeijing102206China Smart Energy Co. LtdChina Xiongan GroupXiong’an New Area071000HebeiChina

Radial borehole fracturing that combines radial boreholes with hydraulic fracturing is anticipated to improve the output of tight oil and gas *** paper aims to investigate fracture propagation and pressure characteristics of radial borehole fracturing in multiple layers.A series of laboratory experiments with artificial rock samples(395 mm×395 mm×395 mm)was conducted using a true triaxial fracturing *** crucial factors corresponding to the vertical distance of adjacent radial borehole layers(vertical distance),the azimuth and diameter of the radial borehole are *** results show that radial borehole fracturing in multiple layers generates diverse fracture *** types of fractures are identified based on the connectivity between hydraulic fractures and radial *** vertical distance significantly influences fracture propagation perpendicular to the radial borehole *** increase in the vertical distance impedes fracture connection across multiple radial borehole layers and reduces the fracture propagation distance along the radial borehole *** azimuth also influences fracture propagation along the radial borehole *** the azimuth reduces the guiding ability of radial boreholes,which makes the fracture quickly curve to the maximum horizontal stress *** breakdown pressure correlates with diverse fracture geometries *** the fractures connect multi-layer radial boreholes,increasing the vertical distance decreases the breakdown *** the azimuth and increasing the diameter also decrease the breakdown *** extrusion force exists between the adjacent fractures generated in radial boreholes in multiple rows,which plays a crucial role in enhancing the guiding ability of radial boreholes and results in higher breakdown *** research provides valuable theoretical insights for the field application of radial borehole fracturing technology in tight oil and g

关键词： Multi-layer radial boreholes Hydraulic fracturing Fracture propagation Pressure characteristic

Wheat 14-3-3 Protein Conferring Growth Retardation in Arabidopsis

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Journal of Integrative Agriculture 2013年第2期12卷 209-217页

作者： LI Jing SONG Su-sheng zhao yu-sheng GUO Wei-wei GUO Guang-hui PENG Hui-ru NI Zhong-fu SUN Qi-xin YAO Ying-yin State Key Laboratory for Agrobiotechnology and Key Laboratory of Crop Heterosis and Utilization Minstry of Education/Key Laboratory of Crop Genomics and Genetic Improvement Minstry of Agriculture/Beijing Key Laboratory of Crop Genetic Improvement China Agricultural University School of Life Sciences Tsinghua University

14-3-3 proteins belong to a family of phosphoserine/threonine-binding modules and participate in a wide array of signal transduction and regulatory events. Our previous study demonstrated that Ta14-3-3 was significantly down-regulated in leaf and root tissues of hybrid wheat at the tillering stage. In this paper, three homoeologous Ta14-3-3 genes were cloned from common wheat （Triticum aestivum L., 2n=6x=42, AABBDD） and mapped on chromosomes 2A, 2B, and 2D, respectively. Transgenic Arabidopsis plants ectopically overexpressing Ta14-3-3 displayed shorter primary roots, delayed flowering and retarded growth rates, indicating that Ta14-3-3 acted as a growth inhibitor in Arabidopsis. In wheat, Ta14-3-3 was down-regulated in roots and leaves of hybrids as compared to their parental lines. We proposed that Ta14-3-3 proteins might regulate growth vigor in hybrid wheat.

关键词： wheat Ta14-3-3 heterosis gene expression

A novel Ce_(0.485)Zr_(0.485)Y_(0.03)O_(2) composite oxide with surface doping of Y and its application in Pd-only three-way catalyst

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Rare Metals 2024年第2期43卷 749-757页

作者： Zheng zhao Wei-Xin zhao Yong-Qi Zhang Mei-sheng Cui Yong-Ke Hou Dong-Ming Chen Juan-yu Yang Zong-yu Feng Xiao-Wei Huang National Engineering Research Center for Rare Earth Grirem Advanced Materials Co.Ltd.GRINM Group Corporation LimitedBeijing100088China Griem Hi-Tech Co.Ltd. Langfang065000China Rare Earth Functional Materials(Xiong’an)Innovation Venter Co.Ltd. Baoding071700China

The ceria-zirconia compound oxide-supported noble metal Pd(Pd@CZ)is widely used in three-way ***,the surface structure of CZ plays an important role in catalytic activity of ***,how to regulate the surface structure of CZ and clarify the structure–activity relationship is still a *** this paper,a strategy is proposed to develop high activity Pd@CZ nanocatalysts by tuning Y doping sites in *** precipitate-deposition method is developed to prepare the novel Ce_(0.485)Zr_(0.485)Y_(0.03)O_(2) composite with surface doping of Y(CZ-Y-S).In addition,the Pd@CZ-Y-S(Pd supported on CZ-Y-S)exhibits superior catalytic activity for HC,CO,and NO oxide,wherein,for CO and C_(3)H_(6) oxidation,the low-temperature activity of Pd@CZ-Y-S is still 20%higher than that of Pd@CZ-Y-B(Y bulk doping)and commercial Pd@CZ after 1000℃/4 h *** effect mechanism is further studied by density functional theory(DFT)*** with Pd@CZ-Y-B,Pd@CZ-Y-S shows the lower CO oxide reaction energy barriers due to the weaker adsorption strength of *** Y surface doping strategy could provide valuable insights for the development of highly efficient Pd@CZ catalyst with extensive applications.

关键词： Rare earth Ceria-zirconia-supported Pd Surface doping Experiment and theory Catalytic application

Wettability and corrosion behavior between alkaline slag from sodium smelting of vanadium-titanium magnetite and refractory substrates

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Journal of Iron and Steel Research International 2024年第6期31卷 1399-1410页

作者： Fei zhao Zhi-wei Bian Hong-xin zhao De-sheng Chen Zhang-fu yuan yu-lan Zhen Li-na Wang Tao Qi Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China National Engineering Research Center of Green Recycling for Strategic Metal Resources Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Hebei Zhongke Tongchuang Vanadium&Titanium Technology Co. Ltd.Hengshui 053000HeheiChina

The sodium smelting of vanadium-titanium magnetite can achieve the comprehensive utilization of Fe,V,and ***,the generation of alkaline slag during this process may cause damage to refractory *** wettability and corrosion behavior of alkaline slag on three types of refractory(MgO-C,SiC,and high alumina refractory)substrates were investigated at temperatures up to 1200℃.The effects of duration on the wettability of molten slag on SiC substrates were also *** showed that the high alumina refractory exhibited better wettability with the molten slag than the others,and thus,it is easier to be *** results of scanning electron microscopy coupled with energy dispersive spectroscopy showed that MgO-C and high alumina refractory substrates were severely *** was a visible and regular interfacial reaction layer between the slag and SiC refractory substrate,which was produced by the redox reaction between the metal oxides in the slag and the SiC refractory *** the increase in holding time,the interface layer expands and silico-ferrite phases are generated at the *** redox reaction between Fe_(2)O_(3) and SiC substrate is the main reason for the *** comparing the differences in wettability and corrosion behavior between the alkaline slag from sodium smelting of vanadium-titanium magnetite and MgO-C,SiC and high alumina refractories,it is concluded that SiC refractory has good corrosion resistance to the *** oxides in the slag accelerate the oxidation rate of SiC refractory.

关键词： Wettability Corrosion Alkaline slag-Contact angle Vanadium-titanium magnetite Refractory