In order to develop a rapid and reliable method for B. cereus genotyping, factors influencing PFGE results, including preparation of bacterial cells embedded in agarose, lysis of embedded cells, enzymatic digestion of...In order to develop a rapid and reliable method for B. cereus genotyping, factors influencing PFGE results, including preparation of bacterial cells embedded in agarose, lysis of embedded cells, enzymatic digestion of intact genomic DNA, and electrophoresis parameters allowing for reproducible and meaningful DNA fragment separation, were controlled. Optimal cellular growth （Luria-Bertani agar plates for 12-18 h） and lysis conditions （4 h incubation with 500 μg/mL lysozyme） produced sharp bands on the gel.展开更多
Formulation of the simplex matrix referred to n-D space, is presented in terms of the scalar product of vectors, known from elementary algebra. The principles of a simplex optimization procedure are presented on a sim...Formulation of the simplex matrix referred to n-D space, is presented in terms of the scalar product of vectors, known from elementary algebra. The principles of a simplex optimization procedure are presented on a simple example, with use of a target function taken as a criterion of optimization, where accuracy and precision are treated equally in searching optimal conditions of a gravimetric analysis.展开更多
The dependence on portable devices and electrical vehicles has triggered the awareness on the energy storage systems with ever-growing energy density.Lithium metal batteries(LMBs)has revived and attracted considerable...The dependence on portable devices and electrical vehicles has triggered the awareness on the energy storage systems with ever-growing energy density.Lithium metal batteries(LMBs)has revived and attracted considerable attention due to its high volumetric(2046 m Ah cm-3),gravimetric specific capacity(3862 m Ah g^(-1))and the lowest reduction potential(-3.04 V vs.SHE.).However,during the electrochemical process of lithium anode,the growth of lithium dendrite constitutes the biggest stumbling block on the road to LMBs application.The undesirable dendrite not only limit the Coulombic efficiency(CE)of LMBs,but also cause thermal runaway and other safety issues due to short-circuits.Understanding the mechanisms of lithium nucleation and dendrite growth provides insights to solve these problems.Herein,we summarize the electrochemical models that inherently describe the lithium nucleation and dendrite growth,such as the thermodynamic,electrodeposition kinetics,internal stress,and interface transmission models.Essential parameters of temperature,current density,internal stress and interfacial Li+flux are focused.To improve the LMBs performance,state-of-the-art optimization procedures have been developed and systematically illustrated with the intrinsic regulation principles for better lithium anode stability,including electrolyte optimization,artificial interface layers,threedimensional hosts,external field,etc.Towards practical applications of LMBs,the current development of pouch cell LMBs have been further introduced with different assembly systems and fading mechanism.However,challenges and obstacles still exist for the development of LMBs,such as in-depth understanding and in-situ observation of dendrite growth,the surface protection under extreme condition and the self-healing of solid electrolyte interface.展开更多
This paper describes an efficient fully programmatic and automated post-layout simulationbased optimization method for analog designs.The proposed methodology is developed to achieve the targeted performance objective...This paper describes an efficient fully programmatic and automated post-layout simulationbased optimization method for analog designs.The proposed methodology is developed to achieve the targeted performance objectives efficiently,that is,with reduced number of iterations and less simulation time,compared to currently predominantly manual design procedures.The efficiency of method is achieved through utilization of expert knowledge at every step of the proposed design process.The expert knowledge is supplied by formalizing the expression of design problems as nested functions,partitioning the design problem in both electrical and physical domains and by selection of starting point for the optimization.The circuit dependencies captured by the nested functions are augmented with backpropagation,similarly as in machinelearning.The proposed methodology provides a fully automated procedure for analog designs that incorporates extracted layout parasitic effects in all phases of the design process without human-in-the-loop.The effectiveness of the methodology is demonstrated with four example circuits:an inverter,a true single-phase clock flip-flop,a source follower,and a bootstrapped sampling switch.The variety of examples represent increasingly complex systems with increasing number of parameters,demonstrating capability of providing analog building blocks from specification to physical implementation without designer intervention.展开更多
基金supported by the National Special Fund for the Development of Major Research Equipment and Instruments(2012YQ09019706)from the Ministry of Science and Technologythe Priority Project on Infectious Disease Control and Prevention(2012ZX10004215 and 2008ZX10004-008)from the National Health and Family Planning Commission of the People's Republic of China
文摘In order to develop a rapid and reliable method for B. cereus genotyping, factors influencing PFGE results, including preparation of bacterial cells embedded in agarose, lysis of embedded cells, enzymatic digestion of intact genomic DNA, and electrophoresis parameters allowing for reproducible and meaningful DNA fragment separation, were controlled. Optimal cellular growth （Luria-Bertani agar plates for 12-18 h） and lysis conditions （4 h incubation with 500 μg/mL lysozyme） produced sharp bands on the gel.
文摘Formulation of the simplex matrix referred to n-D space, is presented in terms of the scalar product of vectors, known from elementary algebra. The principles of a simplex optimization procedure are presented on a simple example, with use of a target function taken as a criterion of optimization, where accuracy and precision are treated equally in searching optimal conditions of a gravimetric analysis.
基金supported by the National Natural Science Foundation of China(51804290,22075025)the Beijing Natural Science Foundation(L182023)+1 种基金the Science and Technology Project of Global Energy Interconnection Research Institute Co.Ltd.(SGGR0000WLJS1900858)the Beijing Institute of Technology Research Fund Program for Young Scholars(2019CX04092)。
文摘The dependence on portable devices and electrical vehicles has triggered the awareness on the energy storage systems with ever-growing energy density.Lithium metal batteries(LMBs)has revived and attracted considerable attention due to its high volumetric(2046 m Ah cm-3),gravimetric specific capacity(3862 m Ah g^(-1))and the lowest reduction potential(-3.04 V vs.SHE.).However,during the electrochemical process of lithium anode,the growth of lithium dendrite constitutes the biggest stumbling block on the road to LMBs application.The undesirable dendrite not only limit the Coulombic efficiency(CE)of LMBs,but also cause thermal runaway and other safety issues due to short-circuits.Understanding the mechanisms of lithium nucleation and dendrite growth provides insights to solve these problems.Herein,we summarize the electrochemical models that inherently describe the lithium nucleation and dendrite growth,such as the thermodynamic,electrodeposition kinetics,internal stress,and interface transmission models.Essential parameters of temperature,current density,internal stress and interfacial Li+flux are focused.To improve the LMBs performance,state-of-the-art optimization procedures have been developed and systematically illustrated with the intrinsic regulation principles for better lithium anode stability,including electrolyte optimization,artificial interface layers,threedimensional hosts,external field,etc.Towards practical applications of LMBs,the current development of pouch cell LMBs have been further introduced with different assembly systems and fading mechanism.However,challenges and obstacles still exist for the development of LMBs,such as in-depth understanding and in-situ observation of dendrite growth,the surface protection under extreme condition and the self-healing of solid electrolyte interface.
基金supported by the Aalto University School of Electrical Engineering.
文摘This paper describes an efficient fully programmatic and automated post-layout simulationbased optimization method for analog designs.The proposed methodology is developed to achieve the targeted performance objectives efficiently,that is,with reduced number of iterations and less simulation time,compared to currently predominantly manual design procedures.The efficiency of method is achieved through utilization of expert knowledge at every step of the proposed design process.The expert knowledge is supplied by formalizing the expression of design problems as nested functions,partitioning the design problem in both electrical and physical domains and by selection of starting point for the optimization.The circuit dependencies captured by the nested functions are augmented with backpropagation,similarly as in machinelearning.The proposed methodology provides a fully automated procedure for analog designs that incorporates extracted layout parasitic effects in all phases of the design process without human-in-the-loop.The effectiveness of the methodology is demonstrated with four example circuits:an inverter,a true single-phase clock flip-flop,a source follower,and a bootstrapped sampling switch.The variety of examples represent increasingly complex systems with increasing number of parameters,demonstrating capability of providing analog building blocks from specification to physical implementation without designer intervention.
