Inverted pendulums are important objects of theoretical investigation and experiment in the area of control theory and engineering. The researches concentrate on the rigid finite dimensional models which are described...Inverted pendulums are important objects of theoretical investigation and experiment in the area of control theory and engineering. The researches concentrate on the rigid finite dimensional models which are described by ordinary differential equations (ODEs) .Complete rigidity is the approximation of practical models ; Elasticity should be introduced into mathematical models in the analysis of system dynamics and integration of highly precise controller. A new kind of inverted pendulum, elastic inverted pendulum was proposed, and elasticity was considered. Mathematical model was derived from Hamiltonian principle and variational methods, which were formulated by the coupling of partial differential equations (PDE) and ODE. Because of infinite dimensional, system analysis and control of elastic inverted pendulum is more sophisticated than the rigid one.展开更多
Strain improvement and medium optimization to increase the productivity of spiramycin were carried out. Of oil tolerant mutant strains screened, one mutant, Streptomyces ambofaciens XC 2-37, produced 9% more spiramyc...Strain improvement and medium optimization to increase the productivity of spiramycin were carried out. Of oil tolerant mutant strains screened, one mutant, Streptomyces ambofaciens XC 2-37, produced 9% more spiramycin than the parent strain S. ambofaciens XC 1-29. The effects of soybean oil and propyl alcohol on spiramycin production with S. ambofaciens XC 2-37 were studied. The potency of S. ambofaciens XC 2-37 was improved by 61.8% with addition of 2% soybean oil in the fermentation medium and 0.4% propyl alcohol at 24 hours after incubation. The suitable time for feeding propyl alcohol is at 24 hours after incubation in flask fermentation and at 20 hours after incubation in fermentor fermentation. The new process with S. ambofaciens XC 2-37 was scaled up for industrial scale production of spiramycin in a 60 m3 fermentor in Xinchang Pharmaceutical Factory, Zhejiang Medicine Company, Ltd., China, and the potency and productivity of fermentation were improved by 42.9%.展开更多
Samarium and a catalytic amount of iodine were used to obtain functionalized cyclopentenes by reductive dimerization followed by intramolecular cyclization of 1， 1-dicyanoalkenes under mild conditions.
The valley shaped Tianziling landfill of Hangzhou in China built in 1991 to dispose of municipal solid waste (MSW) was designed for a service life of 13 years. The problem of waste landfill slope stability and expansi...The valley shaped Tianziling landfill of Hangzhou in China built in 1991 to dispose of municipal solid waste (MSW) was designed for a service life of 13 years. The problem of waste landfill slope stability and expansion must be considered from the geotechnical engineering point of view, for which purpose, it is necessary to understand the geotechnical properties of the MSW in the landfill, some of whose physical properties were measured by common geotechnical tests, such as those on unit weight, water content, organic matter content, specific gravity, coefficient of permeability, compressibility, etc. The mechanical properties were studied by direct shear test, triaxial compression test, and static and dynamic penetration tests. Some strength parameters for engineering analysis were obtained.展开更多
In ionic liquid [Bmim][BF4], a series of disubstituted and trisubstituted thiourea derivativeswere synthesized from phenyl and butyl isothiocyanate with a variety of amine in excellent yield.
Alkoxyalkyl)benzotriazoles are readily synthesized from three-component conden-sation of benzotriazole with aldehyde and alcohol in ionic liquid [Bmim]PF6.
A new method is proposed to study the stability of the car-following model considering traffic interruption probability. The stability condition for the extended ear-following model is obtained by using the Lyapunov f...A new method is proposed to study the stability of the car-following model considering traffic interruption probability. The stability condition for the extended ear-following model is obtained by using the Lyapunov function and the condition for no traffic jam is also given based on the control theory. Numerical simulations are conducted to demonstrate and verify the analytical results. Moreover, numerical simulations show that the traffic interruption probability has an influence on driving behavior and confirm the effectiveness of the method on the stability of traffic flow.展开更多
The present paper employed density function theory to investigate two reaction pathways for isomerization of enol ester proposed by Yang(path a) and the present authors(path a), respectively. The base catalytic effect...The present paper employed density function theory to investigate two reaction pathways for isomerization of enol ester proposed by Yang(path a) and the present authors(path a), respectively. The base catalytic effects of solvent triethylamine on these two reactions were also evaluated. It is demonstrated that path B is more preferable than path a due to low barrier height for the rate-determining step.展开更多
An efficient method is reported for the synthesis of phenacyl esters by reaction of carboxylic acids withα-bromoacetophenone promoted by potassium fluoride in ionic liquid [Bmim]PF6, the yield of the reaction is almo...An efficient method is reported for the synthesis of phenacyl esters by reaction of carboxylic acids withα-bromoacetophenone promoted by potassium fluoride in ionic liquid [Bmim]PF6, the yield of the reaction is almost quantitative and the products are essentially pure.展开更多
Polychlorinated dibenzofurans (PCDFs) represent an important kind of serious pollutant. They are highly toxic and persistent in environment. In this paper, geometrical optimizations and subsequent calculations o...Polychlorinated dibenzofurans (PCDFs) represent an important kind of serious pollutant. They are highly toxic and persistent in environment. In this paper, geometrical optimizations and subsequent calculations of electrostatic potentials (ESPs) on molecular surface have been performed for all 135 PCDF congeners at the HF/6-31G* level. The effects of substitution value and variation of substitution position upon the surface ESPs have been discussed. A series of statistic-based structural descriptors derived from the surface ESPs have been calculated. For some PCDF congeners, linear relationships between aryl hydrocarbon receptor (AhR) biding affinity and aryl hydrocarbon hydroxylase (AHH) induction potency as well as theoretical descriptors have been established by multiple linear regression method. It appears that the quantities derived from the surface ESPs, Vs,min, Vs , VS +, σ+ and Nvmin, 2 together with the molecular surface area and the energy gap between HOMO and LUMO can be well used to express the quantitative structure-toxicity relationships of PCDFs.展开更多
基金This worie was supported by Ningbo Institute of Technology, Zhejiang University (No. 1051157G301).
文摘Inverted pendulums are important objects of theoretical investigation and experiment in the area of control theory and engineering. The researches concentrate on the rigid finite dimensional models which are described by ordinary differential equations (ODEs) .Complete rigidity is the approximation of practical models ; Elasticity should be introduced into mathematical models in the analysis of system dynamics and integration of highly precise controller. A new kind of inverted pendulum, elastic inverted pendulum was proposed, and elasticity was considered. Mathematical model was derived from Hamiltonian principle and variational methods, which were formulated by the coupling of partial differential equations (PDE) and ODE. Because of infinite dimensional, system analysis and control of elastic inverted pendulum is more sophisticated than the rigid one.
文摘Strain improvement and medium optimization to increase the productivity of spiramycin were carried out. Of oil tolerant mutant strains screened, one mutant, Streptomyces ambofaciens XC 2-37, produced 9% more spiramycin than the parent strain S. ambofaciens XC 1-29. The effects of soybean oil and propyl alcohol on spiramycin production with S. ambofaciens XC 2-37 were studied. The potency of S. ambofaciens XC 2-37 was improved by 61.8% with addition of 2% soybean oil in the fermentation medium and 0.4% propyl alcohol at 24 hours after incubation. The suitable time for feeding propyl alcohol is at 24 hours after incubation in flask fermentation and at 20 hours after incubation in fermentor fermentation. The new process with S. ambofaciens XC 2-37 was scaled up for industrial scale production of spiramycin in a 60 m3 fermentor in Xinchang Pharmaceutical Factory, Zhejiang Medicine Company, Ltd., China, and the potency and productivity of fermentation were improved by 42.9%.
基金Preject (No. 20072033) supported by the National Natural Science Foundation of China and Zhejiang Provincial Natural Science Foundation of China
文摘Samarium and a catalytic amount of iodine were used to obtain functionalized cyclopentenes by reductive dimerization followed by intramolecular cyclization of 1， 1-dicyanoalkenes under mild conditions.
文摘The valley shaped Tianziling landfill of Hangzhou in China built in 1991 to dispose of municipal solid waste (MSW) was designed for a service life of 13 years. The problem of waste landfill slope stability and expansion must be considered from the geotechnical engineering point of view, for which purpose, it is necessary to understand the geotechnical properties of the MSW in the landfill, some of whose physical properties were measured by common geotechnical tests, such as those on unit weight, water content, organic matter content, specific gravity, coefficient of permeability, compressibility, etc. The mechanical properties were studied by direct shear test, triaxial compression test, and static and dynamic penetration tests. Some strength parameters for engineering analysis were obtained.
文摘In ionic liquid [Bmim][BF4], a series of disubstituted and trisubstituted thiourea derivativeswere synthesized from phenyl and butyl isothiocyanate with a variety of amine in excellent yield.
文摘Alkoxyalkyl)benzotriazoles are readily synthesized from three-component conden-sation of benzotriazole with aldehyde and alcohol in ionic liquid [Bmim]PF6.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11272160 and 41305016, the Natural Science Foundation of Ningbo under Grant Nos 2014A610028 and 2014A610022, the Ningbo Municipal Fund under Grant No E01194134702, and the K.C. Wong Magna Fund in Ningbo University.
文摘A new method is proposed to study the stability of the car-following model considering traffic interruption probability. The stability condition for the extended ear-following model is obtained by using the Lyapunov function and the condition for no traffic jam is also given based on the control theory. Numerical simulations are conducted to demonstrate and verify the analytical results. Moreover, numerical simulations show that the traffic interruption probability has an influence on driving behavior and confirm the effectiveness of the method on the stability of traffic flow.
文摘The present paper employed density function theory to investigate two reaction pathways for isomerization of enol ester proposed by Yang(path a) and the present authors(path a), respectively. The base catalytic effects of solvent triethylamine on these two reactions were also evaluated. It is demonstrated that path B is more preferable than path a due to low barrier height for the rate-determining step.
文摘An efficient method is reported for the synthesis of phenacyl esters by reaction of carboxylic acids withα-bromoacetophenone promoted by potassium fluoride in ionic liquid [Bmim]PF6, the yield of the reaction is almost quantitative and the products are essentially pure.
基金Supported by the Ph.D. Fund of Ningbo (No. 2004A610010)
文摘Polychlorinated dibenzofurans (PCDFs) represent an important kind of serious pollutant. They are highly toxic and persistent in environment. In this paper, geometrical optimizations and subsequent calculations of electrostatic potentials (ESPs) on molecular surface have been performed for all 135 PCDF congeners at the HF/6-31G* level. The effects of substitution value and variation of substitution position upon the surface ESPs have been discussed. A series of statistic-based structural descriptors derived from the surface ESPs have been calculated. For some PCDF congeners, linear relationships between aryl hydrocarbon receptor (AhR) biding affinity and aryl hydrocarbon hydroxylase (AHH) induction potency as well as theoretical descriptors have been established by multiple linear regression method. It appears that the quantities derived from the surface ESPs, Vs,min, Vs , VS +, σ+ and Nvmin, 2 together with the molecular surface area and the energy gap between HOMO and LUMO can be well used to express the quantitative structure-toxicity relationships of PCDFs.
