Magnetic polymer microspheres can be bonded covalently to antibodies and to otherbiospecific molecules, for instance, cells, enzymes, toxins, hormones, growth factors, nucleicacids, drugs and radioisotopes, for use in...Magnetic polymer microspheres can be bonded covalently to antibodies and to otherbiospecific molecules, for instance, cells, enzymes, toxins, hormones, growth factors, nucleicacids, drugs and radioisotopes, for use in a wide range of biomedical research studies andclinical procedures. Magnetic nanoparticles of iron oxide coated with dextran can be at-tached to bioactive substances by their pendant functional groups, and are small enough展开更多
The maximum effective hole-diameter mathematical modei describing the flow of slightly compressible fluid through a commingled reservoir was solved rigorously with consideration of wellbore storage and different skin ...The maximum effective hole-diameter mathematical modei describing the flow of slightly compressible fluid through a commingled reservoir was solved rigorously with consideration of wellbore storage and different skin factors. The exact solutions for wellbore pressure and the production rate obtained from layer j for a well production at a constant rate from a radial drainage area with infinite and constant pressure and no flow outer boundary condition were expressed in terms of ordinary Bessel functions. These solutions were computed numerically by the Crump's numerical inversion method and the behavior of systems was studied as a function of various reservoir parameters. The modei was compared with the real wellbore radii modei. The new modei is numerically stable when the skin factor is positive and negative, but the real wellbore radii modei is numerically stable only when the skin factor is positive.展开更多
An expanding model of the confinement of non-ideal detonation of small charge is established on the basis of the nozzle theory.Making use of the expanding model,the analytic relationship of small charge detonation vel...An expanding model of the confinement of non-ideal detonation of small charge is established on the basis of the nozzle theory.Making use of the expanding model,the analytic relationship of small charge detonation velocity and the semi-empirical relationship of detonation pressure that both change with charge diameter and confinement condition are established.The detonation velocity and pressure of small charges are calculated and experimentally verified,and the detonation velocity deviation is less than 7% while the detonation pressure deviation is less than 9%.展开更多
The calculation equation of large diameter bored pile's effective length is connected with its distribution of pile shaft resistance. Thus, there is a great difference between the calculation results under the differ...The calculation equation of large diameter bored pile's effective length is connected with its distribution of pile shaft resistance. Thus, there is a great difference between the calculation results under the different distributions of pile shaft resistance. Primarily, this paper summarizes the conceptualized mode of pile shaft resistance under the circum- stance that the soil surrounding the piles presents different layer distributions. Secondly, based on Mindlin's displacement solution and in consideration of the effect of pile diam- eter, the calculation equation is optimized with the assumption that the pile shaft resis- tance has a parabolic distribution. The influencing factors are analyzed according to the calculation result of effective pile length. Finally, combined with an engineering example, the calculation equation deduced in this paper is analyzed and verified. The result shows that both the Poisson ratio of soil and pile diameter have impacted the effective pile length. Compared with the Poisson ratio of soil, the effect of pile diameter is more significant. If the pile diameter remains the same, the effect of the Poisson ratio of soil to the effective pile length decreases as the ratio of pile elastic modulus and soil share modulus increases. If the Poisson ratio of soil remains the same, the effect of the pile diameter to the effective pile length increases as the ratio of pile elastic modulus and soil share modulus increases. Thus the optimized calculation result of pile effective length under the consideration of pile diameter effect is more close to the actual situation of engineering and reasonably practicable.展开更多
The heterojunction of single-wall carbon nanotubes(SWCNTs)and perovskite quantum dots(QDs)shows excellent photodetection performances due to the combination of the advantages of high carrier mobility of SWCNTs and hig...The heterojunction of single-wall carbon nanotubes(SWCNTs)and perovskite quantum dots(QDs)shows excellent photodetection performances due to the combination of the advantages of high carrier mobility of SWCNTs and high absorption coefficient of perovskite QDs.However,the band structure of a SWCNT is determined by its atomic arrangement structure.How the structure of SWCNTs affects the photoelectric performance of the composite film remains elusive.Here,we systematically explored the diameter effect of SWCNTs with different bandgaps on the photodetection performances of SWCNTs/perovskite QDs heterojunction films by integrating semiconducting SWCNTs(s-SWCNTs)with different diameters with CsPbBr3 QDs.The results show that with an increase in diameter of s-SWCNTs,the heterojunction exhibits increasing responsivity(R),detectivity(D*),and faster response time.The great improvement in the optoelectronic performances of devices should be attributed to the higher carrier mobility of larger-diameter SWCNT films and the increasing built-in electric field at the heterojunction interfaces between larger-diameter SWCNTs and CsPbBr3 QDs,which enhances the separation of the photogenerated excitons and the transport of the resulted carriers in SWCNT films.展开更多
Objective To study the effect of self-expanding bare metal stents on the trachea of dogs,and therefore to provide useful information for choice of airway stents by interventional physicians.Methods In this experiment,...Objective To study the effect of self-expanding bare metal stents on the trachea of dogs,and therefore to provide useful information for choice of airway stents by interventional physicians.Methods In this experiment,8beagles were randomly divided into 4 groups.Four selfexpanding metal stents of different diameters(16,18。展开更多
基金Project supported by the National Natural Science Foundation of China.
文摘Magnetic polymer microspheres can be bonded covalently to antibodies and to otherbiospecific molecules, for instance, cells, enzymes, toxins, hormones, growth factors, nucleicacids, drugs and radioisotopes, for use in a wide range of biomedical research studies andclinical procedures. Magnetic nanoparticles of iron oxide coated with dextran can be at-tached to bioactive substances by their pendant functional groups, and are small enough
基金National Natural Science Foundation of China(No.50206016)Special Funds for Major State Basic Research Program of China(973 Program,No.1999022308)
文摘The maximum effective hole-diameter mathematical modei describing the flow of slightly compressible fluid through a commingled reservoir was solved rigorously with consideration of wellbore storage and different skin factors. The exact solutions for wellbore pressure and the production rate obtained from layer j for a well production at a constant rate from a radial drainage area with infinite and constant pressure and no flow outer boundary condition were expressed in terms of ordinary Bessel functions. These solutions were computed numerically by the Crump's numerical inversion method and the behavior of systems was studied as a function of various reservoir parameters. The modei was compared with the real wellbore radii modei. The new modei is numerically stable when the skin factor is positive and negative, but the real wellbore radii modei is numerically stable only when the skin factor is positive.
文摘An expanding model of the confinement of non-ideal detonation of small charge is established on the basis of the nozzle theory.Making use of the expanding model,the analytic relationship of small charge detonation velocity and the semi-empirical relationship of detonation pressure that both change with charge diameter and confinement condition are established.The detonation velocity and pressure of small charges are calculated and experimentally verified,and the detonation velocity deviation is less than 7% while the detonation pressure deviation is less than 9%.
基金supported by the National Natural Science Foundation of China(51208047)
文摘The calculation equation of large diameter bored pile's effective length is connected with its distribution of pile shaft resistance. Thus, there is a great difference between the calculation results under the different distributions of pile shaft resistance. Primarily, this paper summarizes the conceptualized mode of pile shaft resistance under the circum- stance that the soil surrounding the piles presents different layer distributions. Secondly, based on Mindlin's displacement solution and in consideration of the effect of pile diam- eter, the calculation equation is optimized with the assumption that the pile shaft resis- tance has a parabolic distribution. The influencing factors are analyzed according to the calculation result of effective pile length. Finally, combined with an engineering example, the calculation equation deduced in this paper is analyzed and verified. The result shows that both the Poisson ratio of soil and pile diameter have impacted the effective pile length. Compared with the Poisson ratio of soil, the effect of pile diameter is more significant. If the pile diameter remains the same, the effect of the Poisson ratio of soil to the effective pile length decreases as the ratio of pile elastic modulus and soil share modulus increases. If the Poisson ratio of soil remains the same, the effect of the pile diameter to the effective pile length increases as the ratio of pile elastic modulus and soil share modulus increases. Thus the optimized calculation result of pile effective length under the consideration of pile diameter effect is more close to the actual situation of engineering and reasonably practicable.
基金supported by the National Key Research and Development Program of China(Nos.2020YFA0714700 and 2018YFA0208402)the National Natural Science Foundation of China(Nos.51820105002,51872320,51472264,11634014,and 52172060)+2 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB33030100)the Key Research Program of Frontier Sciences,CAS(No.QYZDBSSW-SYS028)the Youth Innovation Promotion Association of CAS(No.2020005).
文摘The heterojunction of single-wall carbon nanotubes(SWCNTs)and perovskite quantum dots(QDs)shows excellent photodetection performances due to the combination of the advantages of high carrier mobility of SWCNTs and high absorption coefficient of perovskite QDs.However,the band structure of a SWCNT is determined by its atomic arrangement structure.How the structure of SWCNTs affects the photoelectric performance of the composite film remains elusive.Here,we systematically explored the diameter effect of SWCNTs with different bandgaps on the photodetection performances of SWCNTs/perovskite QDs heterojunction films by integrating semiconducting SWCNTs(s-SWCNTs)with different diameters with CsPbBr3 QDs.The results show that with an increase in diameter of s-SWCNTs,the heterojunction exhibits increasing responsivity(R),detectivity(D*),and faster response time.The great improvement in the optoelectronic performances of devices should be attributed to the higher carrier mobility of larger-diameter SWCNT films and the increasing built-in electric field at the heterojunction interfaces between larger-diameter SWCNTs and CsPbBr3 QDs,which enhances the separation of the photogenerated excitons and the transport of the resulted carriers in SWCNT films.
文摘Objective To study the effect of self-expanding bare metal stents on the trachea of dogs,and therefore to provide useful information for choice of airway stents by interventional physicians.Methods In this experiment,8beagles were randomly divided into 4 groups.Four selfexpanding metal stents of different diameters(16,18。