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Investigation on the plastic work-heat conversion coefficient of 7075-T651 aluminum alloy during an impact process based on infrared temperature measurement technology

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Acta Mechanica Sinica 2018年第2期34卷 327-333页

作者： Tong Zhang ze-Rong Guo fu-Ping Yuan Hu-Sheng Zhang State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences

The plastic work-heat conversion coefficient is one key parameter for studying the work-heat conversion under dynamic deformation of materials. To explore this coefficient of 7075-T651 aluminum alloy under dynamic compression, dynamic compression experiments using the Hopkinson bar under four groups of strain rates were conducted, and the temperature signals were measured by constructing a transient infrared temperature measurement system. According to stress versus strain data as well as the corresponding temperature data obtained through the experiments, the influences of the strain and the strain rate on the coefficient of plastic work converted to heat were *** experimental results show that the coefficient of plastic work converted to heat of 7075-T651 aluminum alloy is not a constant at the range of 0.85–1 and is closely related to the strain and the strain rate. The change of internal structure of material under high strain rate reduces its energy storage capacity, and makes almost all plastic work convert into heat.

关键词： Plastic work-heat conversion coefficient Infrared temperature measurement Dynamic compression 7075-T651 Aluminum alloy

Significantly enhanced varistor properties of CaCu_(3)Ti_(4)O_(12) based ceramics by designing superior grain boundary:Deepening and broadening interface states

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Journal of Materials Science & Technology 2022年第13期108卷 82-89页

作者： Zhuang Tang Kai Ning Zhiyao fu ze Lian Kangning Wu Shoudao Huang State Key Laboratory of Disaster Prevention and Reduction for Power Grid Transmission and Distribution Equipment SGCC(State Grid Corporation of China)Changsha 410000China College of Electrical and Information Engineering Hunan UniversityChangsha 410082China State Grid Shanxi Electric Power Research Institute Taiyuan 030001China State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi’an 710049China

Significantly enhanced varistor properties via tailoring interface states were obtained in Ca_(1-2x/3)Y_(x)Cu_(3)Ti_(4)O_(12)-SrCu_(3)Ti_(4)O_(12) composite *** breakdown field was improved to 35.8 kV cm^(-1) and the nonlinear coefficient in 0.1-1 mA cm^(-2) was enhanced to 14.6 for Ca_(0.67)Y_(0.5)Cu_(3)Ti_(4)O_(12)-SrCu_(3)Ti_(4)O_(12).Noticeably,the withstand voltage of single grain boundary reached up to 24 V while the reported ones were constant to about 3 *** improved properties were attributed to the formation of superior grain boundary rather than the reduced grain ***,with distinct discrepancy of nonlinear performance in the composites,the resistance and activation energy of grain boundary exhibited little *** on the double Schottky barrier at grain boundary and the field-assisted thermal emission model,it was found that the excellent electrical nonlinearity arose from the formation of deeper and broader interface states at grain *** this case,interface states were not easily entirely filled and the barrier could maintain its height under applied *** work provides a novel routine for enhancing the varistor properties of CaCu_(3)Ti_(4)O_(12) based ceramics by manipulating interface states at grain boundary.

关键词： Schottky barrier Grain boundary Varistor ceramics Interface states

A path planning method for robot patrol inspection in chemical industrial parks

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High Technology Letters 2024年第2期30卷 109-116页

作者：王伟峰 YANG ze LI zhao zhao Xuanchong School of Safety Science and Engineering Xi’an University of Science and TechnologyXi’an 710054P.R.China

Safety patrol inspection in chemical industrial parks is a complex multi-objective task with multiple degrees of *** pointer instruments with advantages like high reliability and strong adaptability to harsh environment,are widely applied in such ***,they rely on manual readings which have problems like heavy patrol workload,high labor cost,high false positives/negatives and poor *** address the above problems,this study proposes a path planning method for robot patrol in chemical industrial parks,where a path optimization model based on improved iterated local search and random variable neighborhood descent(ILS-RVND)algorithm is established by integrating the actual requirements of patrol tasks in chemical industrial ***,the effectiveness of the model and algorithm is verified by taking real park data as an *** results show that compared with GA and ILS-RVND,the improved algorithm reduces quantification cost by about 24%and saves patrol time by about 36%.Apart from shortening the patrol time of robots,optimizing their patrol path and reducing their maintenance loss,the proposed algorithm also avoids the untimely patrol of robots and enhances the safety factor of equipment.

关键词： path planning robot patrol inspection iterated local search and random variableneighborhood descent(ILS-RVND)algorithm

Temporal Dynamics and Performance Association of the Tetrasphaera-Enriched Microbiome for Enhanced Biological Phosphorus Removal

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Engineering 2023年第10期29卷 168-178页

作者： Hui Wang Yubo Wang Guoqing Zhang ze zhao Feng Ju College of Environmental and Resource Sciences Zhejiang UniversityHangzhou 310012China Key Laboratory of Coastal Environment and Resources of Zhejiang Province School of EngineeringWestlake UniversityHangzhou 310024China Institute of Advanced Technology Westlake Institute for Advanced StudyHangzhou 310024China Center of Synthetic Biology and Integrated Bioengineering School of EngineeringWestlake UniversityHangzhou 310024China Research Center for Industries of the future Westlake UniversityHangzhou 310030China

Tetrasphaera have been recently identified based on the 16S ribosomal RNA(rRNA)gene as among the most abundant polyphosphate-accumulating organisms(PAOs)in global full-scale wastewater treatment plants(WWTPs)with enhanced biological phosphorus removal(EBPR).However,it is unclear how Tetrasphaera PAOs are selectively enriched in the context of the EBPR *** this study,an EBPR microbiome enriched with Tetrasphaera(accounting for 40%of 16S sequences on day 113)was built using a top-down design approach featuring multicarbon sources and a low dosage of *** microbiome showed enhanced nutrient removal(phosphorus removal~85%and nitrogen removal~80%)and increased phosphorus recovery(up to 23.2 times)compared with the seeding activated sludge from a local full-scale *** supply of 1 mg·L^(-1)allylthiourea promoted the coselection of Tetrasphaera PAOs and Microlunatus PAOs and sharply reduced the relative abundance of both ammonia oxidizer Nitrosomonas and putative competitors Brevundimonas and Paracoccus,facilitating the establishment of the EBPR *** on 16S rRNA gene analysis,a putative novel PAO species,EBPR-ASV0001,was identified with Tetrasphaera japonica as its closest *** study provides new knowledge on the establishment of a Tetrasphaera-enriched microbiome facilitated by allylthiourea,which can be further exploited to guide future process upgrading and optimization to achieve and/or enhance simultaneous biological phosphorus and nitrogen removal from high-strength wastewater.

关键词： Enhanced biological phosphorus removal(EBPR) Polyphosphate-accumulating organisms(PAOs) Tetrasphaera Microbiome Phosphorus recovery

不同荷载作用下五边形石墨烯的变形破坏机理研究

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原子与分子物理学报 2025年第6期42卷 51-57页

作者：赵泽若韩同伟李仁葛峻铭王嘉越江苏大学土木工程与力学学院镇江212013

五边形石墨烯是一种完全由碳五元环组成的准二维的亚稳态碳结构,在不同载荷作用下其变形破坏机理仍需进一步研究.本文基于ReaxFF反应力场采用分子动力学方法模拟研究了五边形石墨烯的拉伸、剪切和纳米压痕破坏过程,得到了五边形石墨烯... 详细信息

五边形石墨烯是一种完全由碳五元环组成的准二维的亚稳态碳结构,在不同载荷作用下其变形破坏机理仍需进一步研究.本文基于ReaxFF反应力场采用分子动力学方法模拟研究了五边形石墨烯的拉伸、剪切和纳米压痕破坏过程,得到了五边形石墨烯的拉伸和剪切应力-应变曲线以及压入载荷-位移曲线,系统分析了五边形石墨烯的变形破坏机理,并验证了五边形石墨烯在不同载荷作用下是否表现出塑性变形特征的一致性问题.研究结果表明,通过拉伸或纳米压入等不同加载方式均可准确测出五边形石墨烯的本征力学性能参数,其杨氏模量265.4~285.1 N/m,与第一性原理计算结果一致.研究还发现,五边形石墨烯在拉伸、剪切和纳米压痕过程中均会出现不可逆的塑性变形特征,而引起塑性变形的原因是由于不可逆的碳五元环向碳多元环结构的转变.以上研究结果可为基于五边形石墨烯的微/纳米机电系统的实际应用提供重要指导.

关键词：五边形石墨烯变形破坏机理分子动力学

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Analysis of the Light Concentration Loss of a Fresnel CPV/T System after Dust Accumulation

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Journal of Thermal Science 2022年第6期31卷 1868-1880页

作者： zhao Ning YAN Suying MA Xiaodong WU ze MING Tingzhen zhao Xiaoyan ZHANG Na College of Energy and Power Engineering Inner Mongolia University of TechnologyHohhot O10051China School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan 430070China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China

Dust accumulation is one of the reasons for the performance degradation of concentrating photovoltaic and thermal(CPV/T) systems due to the deposition of dust particles with different compositions, shapes, sizes, and masses. In this work, an optical model was developed to investigate the influence of the particle size, diameter, shape, and deposition density on the light concentration efficiency, using the Monte Carlo raytracing(MCRT) method in the Tracepro software. The triangular particles had a larger influence on the light ray deflection and energy flux degradation than the circular and square particles. An average increase in the dust density of 1 g/m^(2) decreased the light concentration efficiency of particles with sizes smaller than 50 μm and 60 μm by 3.31% and 3.26%, respectively. furthermore, the effect of the incidence angle on the light concentration efficiency was considered at an angle less than 2°.

关键词： dust accumulation Fresnel CPV/T system light concentration efficiency Monte Carlo raytracing

High cycle rotating bending fatigue performance and fracture behavior in a pearlite-ferrite dual-phase steel

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Journal of Iron and Steel Research International 2022年第3期29卷 519-528页

作者： Xin-bo Ji Si-xin zhao Li-ming fu Jian Peng Jia-qiang Gao Da-jiang Yu Zong-ze Huang Ai-dang Shan School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai200240China Baosteel Research Institute Baoshan Iron and Steel Co.Ltd.Shanghai201900China

To clarify the effects of ferrite morphologies and contents on high-cycle fatigue property of pearlite-ferrite dual-phase(DP)steel used for fabrication of commercial vehicle crankshafts,two types of DP steels with different ferrite grain sizes(S10:13.1μm and S30:21.4μm)and ferrite contents(S10:~9.5 vol.%and S30:~30.4 vol.%)were *** amplitude-logarithm of number of high cycles to failure fatigue of the two DP steels was *** results showed a fatigue strength of 510 and 400 MPa for S10 and S30 steels,respectively,at 10^(7) *** cracks in S10 steel extended preferentially along the grain boundary,but it was easy for crack propagation to extend within a pearlite colony to form a zigzag crack *** roughness was enhanced and high stress was introduced to the crack surface due to this kind of crack propagation behavior,which has positive effects on slowing down crack ***,the crack propagation in S30 steel mainly occurred inside the soft equiaxed coarse ferrite *** revealed that little stress was introduced to the crack *** results show that it is possible to improve high cycle fatigue strength of pearlite-ferrite DP steel by appropriately manipulating the volume fraction and microstructure morphology of ferrite phase.

关键词： Pearlite-ferrite steel Ferrite morphology Ferrite content Fatigue perfomance Fracture characteristics

Simulation on thermodynamic state of ammonia carbonation at low temperature and low pressure

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Frontiers of Chemical Science and Engineering 2013年第4期7卷 447-455页

作者： Jingcai zhao Xingfu SONG ze SUN Jianguo YU National Engineering Research Center for Integrated Utilization of Salt Lake Resource East China University of Science and Technology Shanghai 200237 China

This study on thermodynamic property of NH3-CO2-H2O system provided the basic data for ammonia carbonation. Simulations on vapor-liquid equili- brium （VLE） of ammonia carbonation with different physical properties were discussed in NH3-H20 and NH3-CO2-H2O systems, respectively. The results indicated that at low temperature （303.15 K363.15 K） and pressure （0.1-0.4MPa）, the PR （Peng-Robinson） equation was suitable for the description of the thermodynamic state in NH3-H2O system. NRTL （Non-Random-Two-Liquid） series models were selected for NH3-CO2-H2O mixed electrolyte solution system. VLE data regression results showed that NRTL series models were suitable for describing thermodynamic properties of NH3-CO2-H2O system, because average relative error fitting with each model was about 1%. As an asymmetric electrolytes model in NRTL model, E-NRTLRK （Electrolyte NRTL Redlich Kwong） could most accurately fit VLE data of NH3-CO2- H2O system, with fitting error less than 1%. In the extent temperature range of 273.15 K363.15 K, the prediction of product component using E-NRTLRK model for ammonia carbonation agreed well with the data reported in literature.

关键词： vapor-liquid equilibrium activity coefficient,carbon dioxide ammonia NRTL

Application of FLUKA and OpenMC in coupled physics calculation of target and subcritical reactor for ADS

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Nuclear Science and Techniques 2019年第1期30卷 113-120页

作者： ze-Long zhao Yong-Wei Yang Shuang Hong Institute of Modern Physics Chinese Academy of Sciences School of Nuclear Science and Technology University of Chinese Academy of Sciences University of Science and Technology Hefei

The study of accelerator-driven subcritical reactor systems(ADSs) has been an important research topic in the field of nuclear energy for years. The main code applied in ADS research is MCNPX, which was developed by Los Alamos National Laboratory. We studied the application of the open-source Monte Carlo codes FLUKA and OpenMC to a coupled ADS calculation. The FLUKA code was used to simulate the reaction of highenergy protons with the nucleus of the target material in the ADS, which produces spallation neutrons. Information on the spallation neutrons, such as their energy, position,direction, and weight, can be recorded by a user-defined routine called FLUSCW provided by FLUKA. Then, the information was stored in an external neutron source file in HDF5 format by using a conversion code, as required by the OpenMC calculation. Finally, the fixed-source calculation function of OpenMC was applied to simulate the transport of spallation neutrons and obtain the distribution of the neutron flux in the core region. In the coupled calculation, the high-energy cross-section library JENDL4.0/HE in ACE format produced by NJOY2016 was applied in the OpenMC transport simulation. The OECD–ADS benchmark problem was calculated, and the results were compared with those obtained using MCNPX. It was found that the flux calculations performed by FLUKA–OpenMC and MCNPX were in agreement, so the coupling calculation method for ADS is reasonable and feasible.

关键词： Accelerator-driven subcritical system MCNPX FLUKA OpenMC JENDL4.0/HE N JOY2016