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Development of index system for inherently safer process design using an integrated approach

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Chinese Journal of Chemical Engineering 2019年第11期27卷 2725-2733页

作者： Junjie Feng Bin Zhang Wei Xu Bing Sun Fan Zhang Jie Jiang State Key Laboratory of Safety and Control for Chemicals SINOPEC Research Institute of Safety EngineeringQingdao 266071China Jiangsu Key Laboratory of Hazardous Chemicals Safety and Control College of Safety Science and EngineeringNanjing Tech UniversityNanjing 211816China

With a growing population, an increasing number of petrochemical facilities are built with larger capacity and more complexity, which pose a great risk to assets, community and environment. The value of inherently safer design is recognized with time by all stakeholders, and an effective tool is needed to evaluate and compare inherent safety of alternative technologies. This study developed a safety index to evaluate existing technologies for their safety levels and guide inherently safer design. The Integrated Risk-based Safety Index(IRSI) was developed based on a comprehensive review of petrochemical processes, incident cases from Sinopec and US Chemical Safety Board, and existing safety index systems. The IRSI included all major hazards, including fire, explosion,toxic release, dust explosion, physical explosion, and runaway. Also, the integrated life cycle approach considered chemical hazards, equipment failure rates and safety measures in this risk-based index. Advanced modeling techniques, PHAST simulation and Neural Network, were used in the development of three novel sub-indices in the projects, fire, explosion and toxic release. The index system could be easily incorporated into a user friendly tool for the ease of application. A case study of hydrogen dioxide was conducted using the IRSI, which showed its capability for evaluating the safety level of process facilities.

关键词： Inherently safety Chemical process safety Integrated risk-based safety index PHAST Hydrogen dioxide

Microstructure evolution and growth mechanism of core-shell silicon-based nanowires by thermal evaporation of SiO

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Journal of Advanced Ceramics 2022年第9期11卷 1417-1430页

作者： bing LIU Jia sun Lei ZHOU Pei ZHANG Chenxin YAN Qiangang FU State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Fiber Reinforced Light Composite MaterialsNorthwestern Polytechnical UniversityXi’an 710072China

Core-shell structured SiC@SiO_(2)nanowires and Si@SiO_(2)nanowires were prepared on the surface of carbon/carbon(C/C)composites by a thermal evaporation method using SiO powders as the silicon source and Ni(NO3)2 as the catalyst.The average diameters of SiC@SiO_(2)nanowires and Si@SiO_(2)nanowires are about 145 nm,and the core-shell diameter ratios are about 0.41 and 0.53,respectively.The SiO_(2)shells of such two nanowires resulted from the reaction between SiO and CO and the reaction of SiO itself,respectively,based on the model analysis.The growth of these two nanowires conformed to the vapor-liquid-solid(VLS)mode.In this mode,CO played an important role in the growth of nanowires.There existed a critical partial pressure of CO(pC)determining the microstructure evolution of nanowires into whether SiC@SiO_(2)or Si@SiO_(2).The value of pC was calculated to be 4.01×10^(-15) Pa from the thermodynamic computation.Once the CO partial pressure in the system was greater than the pC,SiO tended to react with CO,causing the formation of SiC@SiO_(2)nanowires.However,the decomposition of SiO played a predominant role and the products mainly consisted of Si@SiO_(2)nanowires.This work may be helpful for the regulation of the growth process and the understanding of the growth mechanism of silicon-based nanowires.

关键词： SiC@SiO_(2)nanowires Si@SiO_(2)nanowires carbon/carbon(C/C)composites growth mechanism thermal evaporation

Multiscale modeling of heterogeneous propellants from particle packing tograin failure using a surface-based cohesive approach

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Acta Mechanica Sinica 2012年第3期28卷 746-759页

作者： Shi-Jun Zhi Bing Sun Jian-Wei Zhang School of Astronautics Beihang University100191 BeijingChina

In the present work, a computational frame- work is established for multiscale modeling and analysis of solid propellants. A packing algorithm, considering the am- monium perchlorate （AP） and aluminum （A1） particles as spheres or discs is developed to match the size distribution and volume fraction of solid propellants. A homogenization theory is employed to compute the mean stress and strain of a representative volume element （RVE）. Using the mean results, a suitable size of RVE is decided. Without consider- ing the interfaces between particles and matrix, several nu- merical simulations of the relaxation of propellants are per- formed. The relaxation effect and the nonlinear mechanical behavior of propellants which are dependent on the applied loads are discussed. A new technology named surface-based cohesive behavior is proposed to describe the phenomenon of particle dewetting consisting of two ingredients： a damage initiation criterion and a damage evolution law. Several ex- amples considering contact damage behavior are computed and also nonlinear behavior caused by damaged interfaces is discussed in this paper. Furthermore the effects of the criti- cal contact stress, initial contact stiffness and contact failure distance on the damaged interface model have been studied.

关键词： Solid propellants. Nonlinear mechanical behav-ior- Cohesive. Mesomechanics

High‑Energy Room‑Temperature Sodium–Sulfur and Sodium–Selenium Batteries for Sustainable Energy Storage

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Electrochemical Energy Reviews 2023年第1期6卷 87-147页

作者： Zefu Huang Pauline Jaumaux Bing Sun Xin Guo Dong Zhou Devaraj Shanmukaraj Michel Armand Teofilo Rojo Guoxiu Wang Centre for Clean Energy Technology School of Mathematical and Physical SciencesFaculty of ScienceUniversity of Technology SydneyUltimoNSW 2007Australia Centre for Cooperative Research on Alternative Energies(CIC energiGUNE) Basque Research and Technology Alliance(BRTA)Alava Technology ParkAlbert Einstein 4801510 Vitoria-GasteizSpain Inorganic Chemistry Department University of the Basque Country UPV/EHUP.O.Box.64448080 BilbaoSpain

Rechargeable room-temperature sodium–sulfur(Na–S)and sodium–selenium(Na–Se)batteries are gaining extensive attention for potential large-scale energy storage applications owing to their low cost and high theoretical energy density.Optimization of electrode materials and investigation of mechanisms are essential to achieve high energy density and long-term cycling stability of Na–S(Se)batteries.Herein,we provide a comprehensive review of the recent progress in Na–S(Se)batteries.We elucidate the Na storage mechanisms and improvement strategies for battery performance.In particular,we discuss the advances in the development of battery components,including high-performance sulfur cathodes,optimized electrolytes,advanced Na metal anodes and modified separators.Combined with current research achievements,this review outlines remaining challenges and clear research directions for the future development of practical high-performance Na–S(Se)batteries.

关键词： Sodium-sulfur batteries Sodium-selenium batteries Sulfur cathodes Electrolyte engineering Solid-state electrolytes Sodium metal anodes

Mechanism studies of the activation of DNA methyltransferase DNMT1 triggered by histone H3 ubiquitination,revealed by multi-scale molecular dynamics simulations

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Science China(Life Sciences) 2023年第2期66卷 313-323页

作者： Jixue sun Fei Liu Longxiao Yuan Ning-Ning Pang bing Zhu Na Yang State Key Laboratory of Medicinal Chemical Biology College of Pharmacy and Key Laboratory of Medical Data Analysis and Statistical Research of TianjinNankai UniversityTianjin 300353China National Laboratory of Biomacromolecules CAS Center for Excellence in BiomacromoleculesInstitute of BiophysicsChinese Academy of SciencesBeijing 100101China

DNMT1 is a DNA methyltransferase that catalyzes and maintains methylation in CpG dinucleotides.It blocks the entrance of DNA into the catalytic pocket via the replication foci targeting sequence(RFTS)domain.Recent studies have shown that an H3-tail-conjugated two-mono-ubiquitin mark(H3Ub2)activates DNMT1 by binding to the RFTS domain.However,the activation mechanism of DNMT1 remains unclear.In this work,we combine various sampling methods of extensive simulations,including conventional molecular dynamics,Gaussian-accelerated molecular dynamics,and coarse-grained molecular dynamics,to elucidate the activation mechanism of DNMT1.Geometric and energy analyses show that binding of H3Ub2 to the RFTS domain of DNMT1 results in the bending of theα4-helix in the RFTS domain at approximately 30°–35°,and the RFTS domain rotates~20°anti-clockwise and moves~3?away from the target recognition domain(TRD).The hydrogen-bonding network at the RFTSTRD interface is significantly disrupted,implying that the RFTS domain is dissociated from the catalytic core,which contributes to activating the auto-inhibited conformation of DNMT1.These results provide structural and dynamic evidence for the role of H3Ub2 in regulating the catalytic activity of DNMT1.

关键词： DNA methyltransferase conformational change molecular dynamics simulation activation molecular mechanism

Mode-based Damping Torque Analysis in Power System Low-frequency Oscillations

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CSEE Journal of Power and Energy Systems 2023年第4期9卷 1337-1347页

作者： Jingtian Bi Huadong sun Shiyun Xu Ruihua Song bing Zhao Qiang Guo the State Key Laboratory of Power Grid Safety and Energy Conservation China Electric Power Research InstituteBeijing 100192China

The mode-based damping torque analysis(M-DTA)method for studying the effect of an external controller on power system low-frequency oscillations is proposed in this paper.First,based on the interconnection model between the system and the controller in the frequency domain,the oscillation loop corresponding to the electromechanical oscillation mode is built,and then the mode-based damping torque of the controller can be calculated.Then,the application of the M-DTA method in the power system is illustrated.The derivation shows that in the single-machine infinite-bus power system,the M-DTA method is completely equivalent to the classical damping torque analysis(C-DTA)method.In the multi-machine power system,the mode-based damping torque directily reflects the effect of the controller on the oscillation mode,overcoming the shortcomings of the C-DTA method in which there is no direct correspondence between the damping torque and the oscillation mode.By deriving the relationship with the residue index,the M-DTA method shows higher accuracy than the residue method in applications,such as controller parameter adjustment.Finally,two example power systems are presented to demonstrate the application of the proposed M-DTA method.Index Terms-Electromechanical oscillation mode,FACTS,interconnection model in the frequency domain,mode-based damping torque analysis(M-DTA),power system low-frequency oscillation,PSS,residue method.

关键词： Electromechanical oscillation mode FACTS interconnection model in the frequency domain mode-based damping torque analysis(M-DTA) power system low-frequency oscillation PSS residue method.

Discussion on the extended form of internal solitary wave models between two typical stratification systems

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Journal of Hydrodynamics 2023年第1期35卷 155-170页

作者： Jiu-ming Zhang Li Zou Tie-zhi sun Zong-bing Yu Hao Wang School of Naval Architecture State Key Laboratory of Structural Analysis for Industrial EquipmentDalian University of TechnologyDalian116024China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai200240China Institute of Hydrology&Water Resources Tsinghua UniversityBeijing100084China China Institute of Water Resources and Hydropower Research Beijing100038China

The two-layer fluid system and the continuous density system are based on two typical simplified stratification conditions to support the propagation of the internal solitary waves(ISWs).The aim of this study is to establish several extension methods of the classical ISW models across the stratification systems in an attempt to find a simple ISW structure that can propagate more stably,and to determine whether the stable ISW structure in the two typical stratification systems can be expressed in terms of a consistent nonlinear model.For the constructed ISW structures,the propagation stability has been investigated by taking the Euler equations as the evolution equations.The results show that the ISW structure constructed from the Miyata-Choi-Camassa(MCC)model undergoes two stages of instability and the re-stable ISW has a larger available potential energy and a smaller kinetic energy than the initialized condition.This illustrates the limitation of the weakly dispersive assumption in the MCC model.In contrast,the ISW structure constructed from the Dubreil-Jacotin-Long(DJL)model for the two-layer fluid system is generally stable,due to the fact that the Boussinesq approximation introduced in the derivation of the DJL model will be automatically satisfied in this system.The initial condition interpolated from the DJL model with a thin pycnocline thickness can be regarded as an appropriate ISW structure for the two-layer system and is even more stable than that initialized by the MCC model.In addition,the effect of the Boussinesq approximation is also included in the discussion.The approximation can be considered equivalent to a weakly dispersive assumption and should not be ignored for the ISW problem in the continuous density system.

关键词： Internal solitary wave stratification condition the Miyata-Choi-Camassa(MCC)model the Dubreil-Jacotin-Long(DJL)equation Boussinesq approximation

Inherently safer reactors and procedures to prevent reaction runaway

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Chinese Journal of Chemical Engineering 2018年第6期26卷 1252-1263页

作者： Yi Fei Bing Sun Fan Zhang Wei Xu Ning Shi Jie Jiang Research Institute of Safety Engineering SINOPECState Key Laboratory of Safety and Control for Chemicals School of Chemical Engineering China University of Petroleum(East China)

Reaction runaway has longtime been an issue in chemical industry as it often leads to severe accidents if not controlled and inhibited properly.Herein we have reviewed several key considerations and procedures to prevent such phenomena,including inherently safer reactor design,thermal risk assessment and early warning detection of runaway,and pointed out that the basic principle underlying is necessary heat management and construction of resilient processes.For inherently safer reactor design,important factors such as heat removal,heat capacitance,flow behaviors and explosive behaviors have been investigated.The survey shows that heat exchanger(HEX) reactor and microreactor outperform traditional reactors.Meanwhile,we have looked into the effect of thermal risk ranking and safety operation region determining for thermal risk assessment,and the influence of runaway criteria and construction methods for early detection of reaction runaway as well.It shows that thermal risk assessment plays a key role on process design,and early warning detection system(EWDS) is preferable on prevention of reaction runaway.In the end,perspectives regarding inherently safer designs with the measures discussed above have been provided.

关键词：反应堆设计安全严重事故化学工业风险评价热管理 fac

Negative regulation of NLRP3 infl ammasome signaling

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Protein & Cell 2013年第4期4卷 251-258页

作者： Shuzhen Chen Bing Sun State Key Laboratory of Cell Biology Institute of Biochemistry and Cell BiologyShanghai Institutes of Biological SciencesChinese Academy of SciencesShanghai 200031China Key Laboratory of Molecular Virology&Immunology Institute Pasteur of ShanghaiShanghai Institutes of Biological SciencesChinese Academy of SciencesShanghai 200025China

Infl ammasomes are multiprotein complexes that serve as a platform for caspase-1 activation and interleukin-1β(IL-1β)maturation as well as pyroptosis.Though a number of infl ammasomes have been described,the NLRP3 inflammasome is the most extensively studied.NLRP3 inflammasome is triggered by a variety of stimuli,including infection,tissue damage and metabolic dysregulation,and then activated through an integrated cellular signal.Many regulatory mechanisms have been identifi ed to attenuate NLRP3 infl ammasome signaling at multiple steps.Here,we review the developments in the negative regulation of NLRP3 inflammasome that protect host from inflammatory damage.

关键词： infl ammasome NLRP3 negative regulation infl ammation