The photoabsorption cross sections of condensed atoms and molecules have proven to be dependent not only on the imaginary parts but also on the real parts of the polarizabilities due to the strong interatomie interact...The photoabsorption cross sections of condensed atoms and molecules have proven to be dependent not only on the imaginary parts but also on the real parts of the polarizabilities due to the strong interatomie interactions in condensed environment. The real parts of the polarizabilities calculated usually by using the famous Kramers-Kronig transformation (KKT) from the photoabsorption cross sections of the isolated atoms are very sensitive to the accuracy of the implementation method of the infinite integral in the KKT. The influence of the integral instability of the KKT and the real part of the polarizability on the variation of the photoabsorption cross sections with the number density and the structure of the condensed matter has been studied in the present work for the first time. The conclusion is that the integration method with interpolation has given more reasonable results than the direct truncation method if some appropriate interpolation functions have been used. Some notes and conclusions have also been given for the applications of the alternative coupled expressions of photoabsorption cross sections.展开更多
Study of the morphology, aggregation structure and properties ofBombyx mori silk treated by low temperature oxygen plasma showed that slight flutes appeared on the surface of Bombyx mori silk fiber and that its surfac...Study of the morphology, aggregation structure and properties ofBombyx mori silk treated by low temperature oxygen plasma showed that slight flutes appeared on the surface of Bombyx mori silk fiber and that its surface structure changed after plasma treatment. The conformation also changed and crystalline degree decreased. The stannic filling rate of treated fiber was improved. Because of etching, the weight of the fiber decreased but the breaking strength changed little after short-time treatment.展开更多
The eigenstates describing two-component Bose–Einstein condensates (BEC) with weakly excitations have been found, by using the SO(3,2) algebraic mean-field approximation. We show that the two-component modified BEC (...The eigenstates describing two-component Bose–Einstein condensates (BEC) with weakly excitations have been found, by using the SO(3,2) algebraic mean-field approximation. We show that the two-component modified BEC (see Eq.(26)) possesses uniquely super-Poissonian distribution in a fixed magnetic field along direction. The distribution will be uncertain, if B = 0.展开更多
Assembling of a few particles into a cluster commonly occurs in many systems.However,it is still challenging to precisely control particle assembling,due to the various amorphous structures induced by thermal fluctuat...Assembling of a few particles into a cluster commonly occurs in many systems.However,it is still challenging to precisely control particle assembling,due to the various amorphous structures induced by thermal fluctuations during cluster formation.Although these structures may have very different degrees of aggregation,a quantitative method is lacking to describe them,and how these structures evolve remains unclear.Therefore a significant step towards precise control of particle self-assembly is to describe and analyze various aggregation structures during cluster formation quantitatively.In this work,we are motivated to propose a method to directly count and quantitatively compare different aggregated structures.We also present several case studies to evaluate how the aggregated structures during cluster formation are affected by external controlling factors,e.g.,different interaction ranges,interaction strengths,or anisotropy of attraction.展开更多
The traditional reservoir classification methods based on conventional well logging are inefficient for determining the properties,such as the porosity,shale volume,J function,and flow zone index,of the tight sandston...The traditional reservoir classification methods based on conventional well logging are inefficient for determining the properties,such as the porosity,shale volume,J function,and flow zone index,of the tight sandstone reservoirs because of their complex pore structure and large heterogeneity.Specifically,the method that is commonly used to characterize the reservoir pore structure is dependent on the nuclear magnetic resonance(NMR)transverse relaxation time(T2)distribution,which is closely related to the pore size distribution.Further,the pore structure parameters(displacement pressure,maximum pore-throat radius,and median pore-throat radius)can be determined and applied to reservoir classification based on the empirical linear or power function obtained from the NMR T2 distributions and the mercury intrusion capillary pressure ourves.However,the effective generalization of these empirical functions is difficult because they differ according to the region and are limited by the representative samples of different regions.A lognormal distribution is commonly used to describe the pore size and particle size distributions of the rock and quantitatively characterize the reservoir pore structure based on the volume,mean radius,and standard deviation of the small and large pores.In this study,we obtain six parameters(the volume,mean radius,and standard deviation of the small and large pores)that represent the characteristics of pore distribution and rock heterogeneity,calculate the total porosity via NMR logging,and classify the reservoirs via cluster analysis by adopting a bimodal lognormal distribution to fit the NMR T2 spectrum.Finally,based on the data obtained from the core tests and the NMR logs,the proposed method,which is readily applicable,can effectively classify the tight sandstone reservoirs.展开更多
Surface morphologies of the films of poly [styrene-b-(ethylene-co-butene)-b-styrene] (SEBS) have been studied by using tapping-mode atomic force microscopy (TM-AFM). The films of block copolymer were prepared bo...Surface morphologies of the films of poly [styrene-b-(ethylene-co-butene)-b-styrene] (SEBS) have been studied by using tapping-mode atomic force microscopy (TM-AFM). The films of block copolymer were prepared both by spin-coating on mica and by solvent-casting on different solution surfaces. For spin-coating samples, the effect of solution concentration, solvent, and annealing temperature are investigated. It is shown that changing the concentration of the solution makes no difference on the morphology of the film of the block copolymer. The microstructures are quite stable during thermal annealing; only the size of the domains changes toward the equilibrium configuration. However, solvent annealing can notably change the microstructures. When different selective solvents are used for film spin-coating, different morphologies can be obtained and explained by the different solubility parameters of the solvents. As expected, significant different morphologies in the top and the bottom surfaces of the casting films were observed. The images of the top surfaces reveal cylinder microdomains, while those of the bottom surfaces were spherical morphologies.展开更多
Objective: This study was to investigate whether PTEN mutations play a role in the carcinogenesis of soft tissue sarcomas (STS). Methods: Polymerase chain reaction-single strand conformation polymorphism (PCR-SSC...Objective: This study was to investigate whether PTEN mutations play a role in the carcinogenesis of soft tissue sarcomas (STS). Methods: Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) was used to amplify 4 exons of PTEN and to analyze the conformation polymorphism, then DNA sequencing methods was used to detect point mutation of PTEN gene four exons of abnormal single strand conformation in soft tissue sarcomas. Results: Two of 86 cases showed 130th condon G→A missense mutation in the exon 8 of PTEN gene, and this mutation made Arg to change to Gin in PTEN protein structure 334th condon A→T missense mutation in the exon 8 of PTEN gene, and this mutation made Asn to change to Lys in PI-EN protein structure. Conclusion: These data indicated the existence of PTEN mutation in soft tissue sarcomas, but PTEN gene mutation rate is very low. PTEN mutation may prays an less important role in the development and malignant transformation of soft tissue sarcomas.展开更多
The crystallization properties and morphology structure of the cationic dyeable polypropylene fibers which were produced by the blending spinning method were studied by making use of X-ray and scanning electron micros...The crystallization properties and morphology structure of the cationic dyeable polypropylene fibers which were produced by the blending spinning method were studied by making use of X-ray and scanning electron microscopy (SEM). It comes to the conclusions that the larger the crystallite size in the fibers is , the better the dyeable properties of the fibers are and there is a little compatibility between the dyeable agent and polypropylene resin. And the dye-uptake of the fibers may be up to 90% because the dyeable agent can uniformly be scattered in polypropylene.展开更多
Modern public buildings, such as multiplex cinemas and theaters, along with application of state of the art sound effects bring high acoustic insulation demands. Cinemas are often a part of building complexes such as ...Modern public buildings, such as multiplex cinemas and theaters, along with application of state of the art sound effects bring high acoustic insulation demands. Cinemas are often a part of building complexes such as shopping malls with subjects that produce serious level of noise and vibrations. Apart to regular use of polyurethane in thermal insulation purposes, it is widely used in field of acoustic insulation. Usage of polyurethane foam pads, with specific dynamic characteristics, as a base for structure supports gives a wide range of possibilities in controlling the amount of structural noise and vibrations transferred to the structure. Structure itself and acoustical pads becomes an integral system that behaves together and need to be analyzed as a whole in extensive design. Dynamic characteristics of acoustic pads depend on stress level and in same time they represent elastic supports to the structure and therefore analyzes and design is an iterative process. In other way, introduce of non-conventional material in bearing structure brings some issues, such as transfer of shear forces, that has to be governed by proper structural detailing. There are several possibilities of application in bearing structures, such as above and below steel structure. This paper gives an overall view on polyurethane as material, construction and design principles and example of usage of acoustic pads in steel structure of"Ster" cineplex in Belgrade.展开更多
We synthesized hierarchical Polystyrene/Polyaniline@Au(PS/PANI@Au) catalysts through a seeded swelling polymerization and in-situ reduction procedure. PS/PANI@Au catalysts possess a core of PS as seed and template, a ...We synthesized hierarchical Polystyrene/Polyaniline@Au(PS/PANI@Au) catalysts through a seeded swelling polymerization and in-situ reduction procedure. PS/PANI@Au catalysts possess a core of PS as seed and template, a PANI shell with fibers and uniform gold nanoparticles on the surface. The configuration changes of the PANI chains resulting from the doping/ dedoping procedure led to various loading amounts of Au nanoparticles. Reduction of 4-nitrophenol was chosen as the probe reaction to evaluate the catalytic activity of supported Au nanocatalysts. The catalytic results indicated that dedoping treatment of the PS/PANI supports provides stronger coordinative ability to metal nanoparticles as well as more –N= groups, which results in a better catalytic performance towards the reduction of 4-nitrophenol.展开更多
Carbon nanotubes(CNTs) have received broad attention in the past decades due to their excellent physical and chemical properties and thus been regarded as a powerful candidate for future star-materials. Although vario...Carbon nanotubes(CNTs) have received broad attention in the past decades due to their excellent physical and chemical properties and thus been regarded as a powerful candidate for future star-materials. Although various CNT products and their related applications have been demonstrated recently, their performance can hardly meet the researchers’ expectations compared with their theoretical properties. The current predicament is caused by the immature synthesis method, including the basic science and the producing technology. As the synthesis with controlled structures determines its future, this review summarizes the progress on the basic research and industrialization of CNTs in the past decades, including the fine structure control, aggregation status design and scale-up production, and further points out the way for the future development of CNTs combining with specific applications.展开更多
Spin-orbit coupled Bosonic atoms confined in external potentials open up new avenues for quantumstate manipulation and will contribute to the design and exploration of novel quantum devices.Here we consider a quasi-tw...Spin-orbit coupled Bosonic atoms confined in external potentials open up new avenues for quantumstate manipulation and will contribute to the design and exploration of novel quantum devices.Here we consider a quasi-two-dimensional spin-orbit coupled Bose-Einstein condensate confined in an external harmonic potential,with emphasis on the effects of anisotropic spin-orbit coupling on the equilibrium ground-state structure of such a system.For the cases with spin-orbit coupling solely in x- or y-axis direction,the ground-state structure can develop to the well-known standing wave phase,in which the two components always form an alternative density arrangement.For a two-dimensional anisotropic spin-orbit coupling,the separated lumps first become bend,then form two rows of stripe structure along y direction with further increasing the strength of spin-orbit coupling in x-direction.Furthermore,the distance between these two rows of stripe structure is also investigated in detail.展开更多
基金Supported by the Natural Science Foundations of Ludong University under Grant Nos.22270301 and L20072804
文摘The photoabsorption cross sections of condensed atoms and molecules have proven to be dependent not only on the imaginary parts but also on the real parts of the polarizabilities due to the strong interatomie interactions in condensed environment. The real parts of the polarizabilities calculated usually by using the famous Kramers-Kronig transformation (KKT) from the photoabsorption cross sections of the isolated atoms are very sensitive to the accuracy of the implementation method of the infinite integral in the KKT. The influence of the integral instability of the KKT and the real part of the polarizability on the variation of the photoabsorption cross sections with the number density and the structure of the condensed matter has been studied in the present work for the first time. The conclusion is that the integration method with interpolation has given more reasonable results than the direct truncation method if some appropriate interpolation functions have been used. Some notes and conclusions have also been given for the applications of the alternative coupled expressions of photoabsorption cross sections.
文摘Study of the morphology, aggregation structure and properties ofBombyx mori silk treated by low temperature oxygen plasma showed that slight flutes appeared on the surface of Bombyx mori silk fiber and that its surface structure changed after plasma treatment. The conformation also changed and crystalline degree decreased. The stannic filling rate of treated fiber was improved. Because of etching, the weight of the fiber decreased but the breaking strength changed little after short-time treatment.
文摘The eigenstates describing two-component Bose–Einstein condensates (BEC) with weakly excitations have been found, by using the SO(3,2) algebraic mean-field approximation. We show that the two-component modified BEC (see Eq.(26)) possesses uniquely super-Poissonian distribution in a fixed magnetic field along direction. The distribution will be uncertain, if B = 0.
文摘Assembling of a few particles into a cluster commonly occurs in many systems.However,it is still challenging to precisely control particle assembling,due to the various amorphous structures induced by thermal fluctuations during cluster formation.Although these structures may have very different degrees of aggregation,a quantitative method is lacking to describe them,and how these structures evolve remains unclear.Therefore a significant step towards precise control of particle self-assembly is to describe and analyze various aggregation structures during cluster formation quantitatively.In this work,we are motivated to propose a method to directly count and quantitatively compare different aggregated structures.We also present several case studies to evaluate how the aggregated structures during cluster formation are affected by external controlling factors,e.g.,different interaction ranges,interaction strengths,or anisotropy of attraction.
基金supported by the by the National Science and Technology Major Project “Prediction Technique and Evaluation of Tight Oil Sweet Spot”(2016ZX05046-002)
文摘The traditional reservoir classification methods based on conventional well logging are inefficient for determining the properties,such as the porosity,shale volume,J function,and flow zone index,of the tight sandstone reservoirs because of their complex pore structure and large heterogeneity.Specifically,the method that is commonly used to characterize the reservoir pore structure is dependent on the nuclear magnetic resonance(NMR)transverse relaxation time(T2)distribution,which is closely related to the pore size distribution.Further,the pore structure parameters(displacement pressure,maximum pore-throat radius,and median pore-throat radius)can be determined and applied to reservoir classification based on the empirical linear or power function obtained from the NMR T2 distributions and the mercury intrusion capillary pressure ourves.However,the effective generalization of these empirical functions is difficult because they differ according to the region and are limited by the representative samples of different regions.A lognormal distribution is commonly used to describe the pore size and particle size distributions of the rock and quantitatively characterize the reservoir pore structure based on the volume,mean radius,and standard deviation of the small and large pores.In this study,we obtain six parameters(the volume,mean radius,and standard deviation of the small and large pores)that represent the characteristics of pore distribution and rock heterogeneity,calculate the total porosity via NMR logging,and classify the reservoirs via cluster analysis by adopting a bimodal lognormal distribution to fit the NMR T2 spectrum.Finally,based on the data obtained from the core tests and the NMR logs,the proposed method,which is readily applicable,can effectively classify the tight sandstone reservoirs.
基金Supported by the National Natural Science Foundation of China (No. 20476025, No. 20236010, No. 20490200) and ShanghaiMunicipal Education Commission of China
文摘Surface morphologies of the films of poly [styrene-b-(ethylene-co-butene)-b-styrene] (SEBS) have been studied by using tapping-mode atomic force microscopy (TM-AFM). The films of block copolymer were prepared both by spin-coating on mica and by solvent-casting on different solution surfaces. For spin-coating samples, the effect of solution concentration, solvent, and annealing temperature are investigated. It is shown that changing the concentration of the solution makes no difference on the morphology of the film of the block copolymer. The microstructures are quite stable during thermal annealing; only the size of the domains changes toward the equilibrium configuration. However, solvent annealing can notably change the microstructures. When different selective solvents are used for film spin-coating, different morphologies can be obtained and explained by the different solubility parameters of the solvents. As expected, significant different morphologies in the top and the bottom surfaces of the casting films were observed. The images of the top surfaces reveal cylinder microdomains, while those of the bottom surfaces were spherical morphologies.
基金Supported by a grant from the National Natural Science Foundation of China (No. 30560169)
文摘Objective: This study was to investigate whether PTEN mutations play a role in the carcinogenesis of soft tissue sarcomas (STS). Methods: Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) was used to amplify 4 exons of PTEN and to analyze the conformation polymorphism, then DNA sequencing methods was used to detect point mutation of PTEN gene four exons of abnormal single strand conformation in soft tissue sarcomas. Results: Two of 86 cases showed 130th condon G→A missense mutation in the exon 8 of PTEN gene, and this mutation made Arg to change to Gin in PTEN protein structure 334th condon A→T missense mutation in the exon 8 of PTEN gene, and this mutation made Asn to change to Lys in PI-EN protein structure. Conclusion: These data indicated the existence of PTEN mutation in soft tissue sarcomas, but PTEN gene mutation rate is very low. PTEN mutation may prays an less important role in the development and malignant transformation of soft tissue sarcomas.
文摘The crystallization properties and morphology structure of the cationic dyeable polypropylene fibers which were produced by the blending spinning method were studied by making use of X-ray and scanning electron microscopy (SEM). It comes to the conclusions that the larger the crystallite size in the fibers is , the better the dyeable properties of the fibers are and there is a little compatibility between the dyeable agent and polypropylene resin. And the dye-uptake of the fibers may be up to 90% because the dyeable agent can uniformly be scattered in polypropylene.
文摘Modern public buildings, such as multiplex cinemas and theaters, along with application of state of the art sound effects bring high acoustic insulation demands. Cinemas are often a part of building complexes such as shopping malls with subjects that produce serious level of noise and vibrations. Apart to regular use of polyurethane in thermal insulation purposes, it is widely used in field of acoustic insulation. Usage of polyurethane foam pads, with specific dynamic characteristics, as a base for structure supports gives a wide range of possibilities in controlling the amount of structural noise and vibrations transferred to the structure. Structure itself and acoustical pads becomes an integral system that behaves together and need to be analyzed as a whole in extensive design. Dynamic characteristics of acoustic pads depend on stress level and in same time they represent elastic supports to the structure and therefore analyzes and design is an iterative process. In other way, introduce of non-conventional material in bearing structure brings some issues, such as transfer of shear forces, that has to be governed by proper structural detailing. There are several possibilities of application in bearing structures, such as above and below steel structure. This paper gives an overall view on polyurethane as material, construction and design principles and example of usage of acoustic pads in steel structure of"Ster" cineplex in Belgrade.
基金financially supported by the National Natural Science Foundation of China(51272028)PetroChina Innovation Foundation(2012D-5006-0504)
文摘We synthesized hierarchical Polystyrene/Polyaniline@Au(PS/PANI@Au) catalysts through a seeded swelling polymerization and in-situ reduction procedure. PS/PANI@Au catalysts possess a core of PS as seed and template, a PANI shell with fibers and uniform gold nanoparticles on the surface. The configuration changes of the PANI chains resulting from the doping/ dedoping procedure led to various loading amounts of Au nanoparticles. Reduction of 4-nitrophenol was chosen as the probe reaction to evaluate the catalytic activity of supported Au nanocatalysts. The catalytic results indicated that dedoping treatment of the PS/PANI supports provides stronger coordinative ability to metal nanoparticles as well as more –N= groups, which results in a better catalytic performance towards the reduction of 4-nitrophenol.
基金supported by the Ministry of Science and Technology of China (2016YFA0200101 and 2016YFA0200104)the National Natural Science Foundation of China (51432002, 21790052 and 51720105003)+2 种基金Beijing Municipal Science and Technology Planning Project (Z161100002116026)China PostdoctoralScience Foundation (8201400852 and 8201400892)the National Program for Thousand Young Talents of China
文摘Carbon nanotubes(CNTs) have received broad attention in the past decades due to their excellent physical and chemical properties and thus been regarded as a powerful candidate for future star-materials. Although various CNT products and their related applications have been demonstrated recently, their performance can hardly meet the researchers’ expectations compared with their theoretical properties. The current predicament is caused by the immature synthesis method, including the basic science and the producing technology. As the synthesis with controlled structures determines its future, this review summarizes the progress on the basic research and industrialization of CNTs in the past decades, including the fine structure control, aggregation status design and scale-up production, and further points out the way for the future development of CNTs combining with specific applications.
基金Supported by National Natural Science Foundation of China under Grant No.61361002the Applied Fundamental Research Projects of Yunnan Province under Grant No.2013FZ121
文摘Spin-orbit coupled Bosonic atoms confined in external potentials open up new avenues for quantumstate manipulation and will contribute to the design and exploration of novel quantum devices.Here we consider a quasi-two-dimensional spin-orbit coupled Bose-Einstein condensate confined in an external harmonic potential,with emphasis on the effects of anisotropic spin-orbit coupling on the equilibrium ground-state structure of such a system.For the cases with spin-orbit coupling solely in x- or y-axis direction,the ground-state structure can develop to the well-known standing wave phase,in which the two components always form an alternative density arrangement.For a two-dimensional anisotropic spin-orbit coupling,the separated lumps first become bend,then form two rows of stripe structure along y direction with further increasing the strength of spin-orbit coupling in x-direction.Furthermore,the distance between these two rows of stripe structure is also investigated in detail.