[Objective] The aim was to provide molecular basis for the identification of species in the moss family Bryaceae by the construction of inter-simple sequence repeats （ISSR） fingerprinting. [Method] In order to seek ...[Objective] The aim was to provide molecular basis for the identification of species in the moss family Bryaceae by the construction of inter-simple sequence repeats （ISSR） fingerprinting. [Method] In order to seek standardizing PCR reaction set-up, an orthogonal design was used to optimize ISSR-PCR amplification system of Bryaceae in five factors （Mg2＋, dNTPs, primer, DNA template, Taq DNA polymerase） at four levels respectively. [Result] A suitable ISSR reaction system was obtained, namely： 20 μl reaction system containing 5 ng of DNA template, 0.2 μmol/L primer, 2.25 mmol/L MgCl2, 0.6 U of Taq DNA polymerase, 0.4 mmol/L dNTPs. Proper annealing temperature was found at 48-50 ℃.The above system and six ISSR-PCR primers were used for the PCR amplification of 14 samples from Bryaceae and the related species in Mniaceae. A total of 86 bands were amplified, all showed polymorphism. NJ cluster analysis showed a star-shaped cladogram. [Conclusion] The results manifested that ISSR fingerprinting could provide the appropriate degree of polymorphism at low taxonomic level, so it would be a useful tool to provide additional evidence for resolving taxonomic relationships at the species level of Bryaceae.展开更多
The kinetics of the decomposition of dimethylhexane-1,6-dicarbamate to 1,6-hexamethylene diisocyanate was studied. A consecutive reaction model was established and the reaction orders for the two steps were confirmed ...The kinetics of the decomposition of dimethylhexane-1,6-dicarbamate to 1,6-hexamethylene diisocyanate was studied. A consecutive reaction model was established and the reaction orders for the two steps were confirmed to be 1 and 1.3 by the integral test method and the numerical differential method, respectively. The activation energies of the two steps were （56.94 4±5.90） kJ·mol^-1 and （72.07±3.47） kJ·mol^-1 with the frequency factors exp（ 12.53±1.42） min^- 1 and （ 14.254±0.84） tool^-0.33. L^0.33·min^-1, respectively. Based on the kinetic model obtained, the progress of the reaction can be calculated under given conditions.展开更多
Overmany alarms of modern chemical process give the operators many difficulties to decision and diag- nosis. In order to ensure safe production and process operating, management and optimization of alarm information a...Overmany alarms of modern chemical process give the operators many difficulties to decision and diag- nosis. In order to ensure safe production and process operating, management and optimization of alarm information are challenge work that must be confronted. A new process alarm management method based on fuzzy clustering- ranking algorithm is proposed. The fuzzy clustering algorithm is used to cluster rationally the process variables, and difference driving decision algorithm ranks different clusters and process parameters in every cluster. The alarm signal of higher rank is handled preferentially to manage effectively alarms and avoid blind operation. The validity of proposed algorithm and solution is verified by the practical application of ethylene cracking furnace system. It is an effective and dependable alarm management method to improve operating safety in industrial process.展开更多
The X-ray low angle reflectivity measurement is used to investigate single and bilayer films to determine the parameters of nanometer-scale structures,three effectual methods are presented by using X-ray reflectivity ...The X-ray low angle reflectivity measurement is used to investigate single and bilayer films to determine the parameters of nanometer-scale structures,three effectual methods are presented by using X-ray reflectivity analysis to provide an accurate estimation of the nanometer film structures. The parameters of tungsten (W) single layer, such as the material density, interface roughness and deposition rate, were obtained easily and speedily. The base metal layer was introduced to measure the profiles of single low Z material film. A 0.3 nm chromium (Cr) film was also studied by low angle reflectivity analysis.展开更多
This paper presents an experimental investigation of the turbulent reacting flow in a swirl combustor with staged air injection. The air injected into the combustor is composed of the primary swirling jet and the seco...This paper presents an experimental investigation of the turbulent reacting flow in a swirl combustor with staged air injection. The air injected into the combustor is composed of the primary swirling jet and the secon-dary non-swirling jet. A three dimension-laser particle dynamic analyzer (PDA) was employed to measure the in-stantaneous gas velocity. The probability density functions (PDF) for the instantaneous gas axial and tangential ve-locities at each measuring location, as well as the radial profiles of the root mean square of fluctuating gas axial and tangential velocities and the second-order moment for the fluctuating gas axial and tangential velocities are ob-tained. The measured results delineate the turbulence properties of the swirling reacting flow under the conditions of staged combustion.展开更多
This paper is a complement and extension of the theory of generalized tautology which was first proposed by Wang Guojun in revised Kleene system, Some interesting results are obtained: (i) accessibleα +-tautology and...This paper is a complement and extension of the theory of generalized tautology which was first proposed by Wang Guojun in revised Kleene system, Some interesting results are obtained: (i) accessibleα +-tautology and generalized contradiction which are dual theory to generalized tautology have been introduced; (ii) congruence partition about—has been given in logic system $\bar W$ ,W k ; (iii) in logic systemW k , tautologies can be obtained by employing the upgrade algorithm at most $\left[ {\frac{{k + 1}}{2}} \right]$ times to an arbitrary formula; (iv) in logic system $\bar W(W)$ , tautologies cannot be obtained by employing upgrade algorithm to non-tautologies within finitely many times; (v) the deduction rule $\left( {\left[ {\left( {\frac{1}{2}} \right)^ + } \right] - MP} \right)$ holds in logic system $\bar W(W)$ .展开更多
This paper studies the robust H∞ disturbance attenuation with internal stability for uncertain nonlinear control systems. By adding one power integrator technique, this paper designs a explicit smooth robust dynamic ...This paper studies the robust H∞ disturbance attenuation with internal stability for uncertain nonlinear control systems. By adding one power integrator technique, this paper designs a explicit smooth robust dynamic feedback law while rejecting the disturbance to any specified degree of accuracy. Further, the example and simulation results show the effectiveness of the proposed schemes.展开更多
Rational composition design of trimetallic phosphide catalysts is of significant importance for enhanced surface reaction and efficient catalytic performance.Herein,hierarchical Co_(x)Ni_(y)Fe_(z)P with precise contro...Rational composition design of trimetallic phosphide catalysts is of significant importance for enhanced surface reaction and efficient catalytic performance.Herein,hierarchical Co_(x)Ni_(y)Fe_(z)P with precise control of stoichiometric metallic elements(x:y:z=(1-10):(1-10):1)has been synthesized,and Co_(1.3)Ni_(0.5)Fe_(0.2)P,as the most optimal composition,exhibits remarkable catalytic activity(η=320 mV at 10 mA cm^(−2))and long-term stability(ignorable decrease after 10 h continuous test at the current density of 10 mA cm^(−2))toward oxygen evolution reaction(OER).It is found that the surface P in Co_(1.3)Ni_(0.5)Fe_(0.2)P was replaced by O under the OER process.The density function theory calculations before and after long-term stability tests suggest the clear increasing of the density of states near the Fermi level of Co_(1.3)Ni_(0.5)Fe_(0.2)P/Co_(1.3)Ni_(0.5)Fe_(0.2)O,which could enhance the OH−adsorption of our electrocatalysts and the corresponding OER performance.展开更多
This paper addresses a hierarchical sliding-mode control method for an inverted pendulum system. In this method, the system states are divided into two groups and a kind of two-layer sliding plane is constructed. We c...This paper addresses a hierarchical sliding-mode control method for an inverted pendulum system. In this method, the system states are divided into two groups and a kind of two-layer sliding plane is constructed. We can derive the sliding-mode control law which includes the equivalent control of every sub-sliding plane by using Lyapunov law, therefore the total sliding-mode control law can drive every subsystem to move along its own sub-sliding plane, then the asymptotical stability of all the sliding planes is proved.展开更多
基金Supported by Natural Science Foundation of Hebei Province(C2006000147)Zhengzhou Science and Technology Program(10PTGN449-6)~~
文摘[Objective] The aim was to provide molecular basis for the identification of species in the moss family Bryaceae by the construction of inter-simple sequence repeats （ISSR） fingerprinting. [Method] In order to seek standardizing PCR reaction set-up, an orthogonal design was used to optimize ISSR-PCR amplification system of Bryaceae in five factors （Mg2＋, dNTPs, primer, DNA template, Taq DNA polymerase） at four levels respectively. [Result] A suitable ISSR reaction system was obtained, namely： 20 μl reaction system containing 5 ng of DNA template, 0.2 μmol/L primer, 2.25 mmol/L MgCl2, 0.6 U of Taq DNA polymerase, 0.4 mmol/L dNTPs. Proper annealing temperature was found at 48-50 ℃.The above system and six ISSR-PCR primers were used for the PCR amplification of 14 samples from Bryaceae and the related species in Mniaceae. A total of 86 bands were amplified, all showed polymorphism. NJ cluster analysis showed a star-shaped cladogram. [Conclusion] The results manifested that ISSR fingerprinting could provide the appropriate degree of polymorphism at low taxonomic level, so it would be a useful tool to provide additional evidence for resolving taxonomic relationships at the species level of Bryaceae.
基金the National Key Technology R&D Program(2013BAC11B03)the Knowledge Innovation Fund of Chinese Academy of Science(KGCX2-YW-215-2)the National Natural Science Foundation of China(21476244)
文摘The kinetics of the decomposition of dimethylhexane-1,6-dicarbamate to 1,6-hexamethylene diisocyanate was studied. A consecutive reaction model was established and the reaction orders for the two steps were confirmed to be 1 and 1.3 by the integral test method and the numerical differential method, respectively. The activation energies of the two steps were （56.94 4±5.90） kJ·mol^-1 and （72.07±3.47） kJ·mol^-1 with the frequency factors exp（ 12.53±1.42） min^- 1 and （ 14.254±0.84） tool^-0.33. L^0.33·min^-1, respectively. Based on the kinetic model obtained, the progress of the reaction can be calculated under given conditions.
基金Partially supported by the National Natural Science Foundation of China (No. 29976003), the Key Research Project ofScience and Technology from Ministry of Education in China (No. 01024), and Sinopec Science & Technology DevelopmentProject (No. E03007)
文摘Overmany alarms of modern chemical process give the operators many difficulties to decision and diag- nosis. In order to ensure safe production and process operating, management and optimization of alarm information are challenge work that must be confronted. A new process alarm management method based on fuzzy clustering- ranking algorithm is proposed. The fuzzy clustering algorithm is used to cluster rationally the process variables, and difference driving decision algorithm ranks different clusters and process parameters in every cluster. The alarm signal of higher rank is handled preferentially to manage effectively alarms and avoid blind operation. The validity of proposed algorithm and solution is verified by the practical application of ethylene cracking furnace system. It is an effective and dependable alarm management method to improve operating safety in industrial process.
基金This work was supported by the National Natural Science Foun-dation of China(10435050,60378021)the National 863-804Sustentation Fund(2006AA12Z139)+2 种基金the Program for New Cen-tury Excellent Talents in University(NCET-04-037)the RoyalSociety,London(NC/China/16660)Tongji University scien-tific fund.
文摘The X-ray low angle reflectivity measurement is used to investigate single and bilayer films to determine the parameters of nanometer-scale structures,three effectual methods are presented by using X-ray reflectivity analysis to provide an accurate estimation of the nanometer film structures. The parameters of tungsten (W) single layer, such as the material density, interface roughness and deposition rate, were obtained easily and speedily. The base metal layer was introduced to measure the profiles of single low Z material film. A 0.3 nm chromium (Cr) film was also studied by low angle reflectivity analysis.
基金Supported jointly by the National Natural Science Foundation of China (No.59806006) and the Laboratory Open Fund ofTsinghua University.
文摘This paper presents an experimental investigation of the turbulent reacting flow in a swirl combustor with staged air injection. The air injected into the combustor is composed of the primary swirling jet and the secon-dary non-swirling jet. A three dimension-laser particle dynamic analyzer (PDA) was employed to measure the in-stantaneous gas velocity. The probability density functions (PDF) for the instantaneous gas axial and tangential ve-locities at each measuring location, as well as the radial profiles of the root mean square of fluctuating gas axial and tangential velocities and the second-order moment for the fluctuating gas axial and tangential velocities are ob-tained. The measured results delineate the turbulence properties of the swirling reacting flow under the conditions of staged combustion.
文摘This paper is a complement and extension of the theory of generalized tautology which was first proposed by Wang Guojun in revised Kleene system, Some interesting results are obtained: (i) accessibleα +-tautology and generalized contradiction which are dual theory to generalized tautology have been introduced; (ii) congruence partition about—has been given in logic system $\bar W$ ,W k ; (iii) in logic systemW k , tautologies can be obtained by employing the upgrade algorithm at most $\left[ {\frac{{k + 1}}{2}} \right]$ times to an arbitrary formula; (iv) in logic system $\bar W(W)$ , tautologies cannot be obtained by employing upgrade algorithm to non-tautologies within finitely many times; (v) the deduction rule $\left( {\left[ {\left( {\frac{1}{2}} \right)^ + } \right] - MP} \right)$ holds in logic system $\bar W(W)$ .
基金The research is supported by the Natural Science Foundation of Henan Province under Grant No. 2007120005.
文摘This paper studies the robust H∞ disturbance attenuation with internal stability for uncertain nonlinear control systems. By adding one power integrator technique, this paper designs a explicit smooth robust dynamic feedback law while rejecting the disturbance to any specified degree of accuracy. Further, the example and simulation results show the effectiveness of the proposed schemes.
基金financially supported by the National Natural Science Foundation of China (51861135313)Sino-German Center COVID-19 Related Bilateral Collaborative project (C-0046)+7 种基金FRFCU(2021qntd13)the National 111 project (B20002)Guangdong Basic and Applied Basic Research Foundation (2019A1515110436, 2021A15151111312022A1515011905)Guangdong Province International Scientific and Technological Cooperation Projects (2020A0505100036)Guangzhou Science and Technology Project (202102020463)Shenzhen Science and Technology Program (JCYJ20210324142010029)DSI/NRF/WITS South African Research Chair Initiative (SARChI) Chair (132739)。
文摘Rational composition design of trimetallic phosphide catalysts is of significant importance for enhanced surface reaction and efficient catalytic performance.Herein,hierarchical Co_(x)Ni_(y)Fe_(z)P with precise control of stoichiometric metallic elements(x:y:z=(1-10):(1-10):1)has been synthesized,and Co_(1.3)Ni_(0.5)Fe_(0.2)P,as the most optimal composition,exhibits remarkable catalytic activity(η=320 mV at 10 mA cm^(−2))and long-term stability(ignorable decrease after 10 h continuous test at the current density of 10 mA cm^(−2))toward oxygen evolution reaction(OER).It is found that the surface P in Co_(1.3)Ni_(0.5)Fe_(0.2)P was replaced by O under the OER process.The density function theory calculations before and after long-term stability tests suggest the clear increasing of the density of states near the Fermi level of Co_(1.3)Ni_(0.5)Fe_(0.2)P/Co_(1.3)Ni_(0.5)Fe_(0.2)O,which could enhance the OH−adsorption of our electrocatalysts and the corresponding OER performance.
文摘This paper addresses a hierarchical sliding-mode control method for an inverted pendulum system. In this method, the system states are divided into two groups and a kind of two-layer sliding plane is constructed. We can derive the sliding-mode control law which includes the equivalent control of every sub-sliding plane by using Lyapunov law, therefore the total sliding-mode control law can drive every subsystem to move along its own sub-sliding plane, then the asymptotical stability of all the sliding planes is proved.
