We present the feasibility study of nonlinear dielectrics for the energy storage applications. Corona deposition of electric charges to the surface of thin films of highly polarizable organic molecules (dielectrophore...We present the feasibility study of nonlinear dielectrics for the energy storage applications. Corona deposition of electric charges to the surface of thin films of highly polarizable organic molecules (dielectrophores) shows that the electric field inside the dielectric has a highly nonlinear response. The stored energy densities are superior to the polypropylene films, measured for the comparison, and at least comparable to the current electrochemical batteries. These results make us believe that the dielectrophores-based electrostatic capacitors can revolutionize the energy storage market.展开更多
Composites of carbon aerogel and graphite oxide(GO) were synthesized using a self-assembly method based on dispersive forces. Their surface was modified by treatment in hydrogen sulfide at 650 and800 ℃. The samples...Composites of carbon aerogel and graphite oxide(GO) were synthesized using a self-assembly method based on dispersive forces. Their surface was modified by treatment in hydrogen sulfide at 650 and800 ℃. The samples obtained were characterized by adsorption of nitrogen, TA-MS, XPS, potentiometric titration, and HRTEM and tested as catalysts for oxygen reduction reactions(ORR) in an alkaline medium.The synergistic effect of the composite(electrical conductivity, porosity and surface chemistry) leads to a good ORR catalytic activity. The onset potential for the composite of carbon aerogel heated at 800 ℃ is shifted to a more positive value and the number of electron transfer was 2e-at the potential 0.68 V versus RHE and it increased to 4e-with an increase in the negative values of the potential. An excellent tolerance to methanol crossover was also recorded.展开更多
Fitting parametric models to globular clusters’structural profiles has been essential for the study of stellar dynamics.It provides their important structural parameters,such as the concentrations and core radii of t...Fitting parametric models to globular clusters’structural profiles has been essential for the study of stellar dynamics.It provides their important structural parameters,such as the concentrations and core radii of the clusters.However,existing parametric models can apply only to non-collapsing-core clusters in the early relaxation-evolution stage.Hence,a single parametric model cannot provide globular clusters’structural parameters in both the early and late evolution stages.We have recently found an accurate spectral solution for the self-similar orbit-averaged Fokker-Planck(OAFP)equation to model collapsingcore clusters at the late evolution stage.The present work establishes a new parametric model by combining the self-similar OAFP-and polytropic-models.Although it is a single-mass and isotropic model,the new model applies to at least fifty-five Galactic globular clusters with resolved cores in all the evolution stages.As a main result,we show the characteristics of the relaxation times against the concentrations of the clusters.We also affirm that the structures of low-concentration clusters are polytropic in the Milky Way.展开更多
We examine 10 nm thick film structures containing either Hf or Ti sandwiched between two respective oxide layers. The layers are deposited onto heated substrates to create a diffusion region. We observe a high degree ...We examine 10 nm thick film structures containing either Hf or Ti sandwiched between two respective oxide layers. The layers are deposited onto heated substrates to create a diffusion region. We observe a high degree of light sensitivity of the electric current through the film thickness for one polarity of an applied voltage. For the other polarity, the current is not affected by the light. We explain the observed phenomenology using the single-particle model based on the existence of interface states on the metal-oxide interfaces.展开更多
We map the requirements and design rules for dielectric materials that target large scale energy storage applications of electrostatic capacitors. The molecular unit (dielectrophore) must contain three main components...We map the requirements and design rules for dielectric materials that target large scale energy storage applications of electrostatic capacitors. The molecular unit (dielectrophore) must contain three main components: a polarizable subunit having large electric dipole, an isolating subunit which prevents current leakage, and a structural element that promotes self-assembly of molecules in solution and in mesophase and promotes crystallization in the process of film formation. This structural subunit is necessary for high molecular density and enhanced resistivity of film. The process engineering steps required for the supramolecular assembly and crystal film formation (cascade crystallization) are addressed.展开更多
Main design principles of the potent rylene-based class of dielectrophores are established in the present article. The proposed class of dielectrophores comprises polarizable aromatic core, conjugated with aromatic su...Main design principles of the potent rylene-based class of dielectrophores are established in the present article. The proposed class of dielectrophores comprises polarizable aromatic core, conjugated with aromatic subunits, and bears resistive groups on the periphery. The aromatic subunits might comprise donor and acceptor groups for the desired level of polarizability of the molecule. Appropriate positions for donor and acceptor groups are established by quantum chemistry modeling. The design principles are demonstrated on the molecular design of an efficient rylene-based dielectrophore.展开更多
We experimentally demonstrate and numerically analyze large arrays of whispering gallery resonators.Using fluorescent mapping,we measure the spatial distribution of the cavity ensemble’s resonances,revealing that lig...We experimentally demonstrate and numerically analyze large arrays of whispering gallery resonators.Using fluorescent mapping,we measure the spatial distribution of the cavity ensemble’s resonances,revealing that light reaches distant resonators in various ways,including while passing through dark gaps,resonator groups,or resonator lines.Energy spatially decays exponentially in the cavities.Our practically infinite periodic array of resonators,with a quality factor(Q)exceeding 107,might impact a new type of photonic ensembles for nonlinear optics and lasers using our cavity continuum that is distributed,while having high-Q resonators as unit cells.展开更多
文摘We present the feasibility study of nonlinear dielectrics for the energy storage applications. Corona deposition of electric charges to the surface of thin films of highly polarizable organic molecules (dielectrophores) shows that the electric field inside the dielectric has a highly nonlinear response. The stored energy densities are superior to the polypropylene films, measured for the comparison, and at least comparable to the current electrochemical batteries. These results make us believe that the dielectrophores-based electrostatic capacitors can revolutionize the energy storage market.
基金supported by the Spanish Ministry of Economy and Competitiveness (Project CTQ2012-37925-C03-03)FEDER fundsby the Hungarian National Fund OTKA K109558
文摘Composites of carbon aerogel and graphite oxide(GO) were synthesized using a self-assembly method based on dispersive forces. Their surface was modified by treatment in hydrogen sulfide at 650 and800 ℃. The samples obtained were characterized by adsorption of nitrogen, TA-MS, XPS, potentiometric titration, and HRTEM and tested as catalysts for oxygen reduction reactions(ORR) in an alkaline medium.The synergistic effect of the composite(electrical conductivity, porosity and surface chemistry) leads to a good ORR catalytic activity. The onset potential for the composite of carbon aerogel heated at 800 ℃ is shifted to a more positive value and the number of electron transfer was 2e-at the potential 0.68 V versus RHE and it increased to 4e-with an increase in the negative values of the potential. An excellent tolerance to methanol crossover was also recorded.
文摘Fitting parametric models to globular clusters’structural profiles has been essential for the study of stellar dynamics.It provides their important structural parameters,such as the concentrations and core radii of the clusters.However,existing parametric models can apply only to non-collapsing-core clusters in the early relaxation-evolution stage.Hence,a single parametric model cannot provide globular clusters’structural parameters in both the early and late evolution stages.We have recently found an accurate spectral solution for the self-similar orbit-averaged Fokker-Planck(OAFP)equation to model collapsingcore clusters at the late evolution stage.The present work establishes a new parametric model by combining the self-similar OAFP-and polytropic-models.Although it is a single-mass and isotropic model,the new model applies to at least fifty-five Galactic globular clusters with resolved cores in all the evolution stages.As a main result,we show the characteristics of the relaxation times against the concentrations of the clusters.We also affirm that the structures of low-concentration clusters are polytropic in the Milky Way.
文摘We examine 10 nm thick film structures containing either Hf or Ti sandwiched between two respective oxide layers. The layers are deposited onto heated substrates to create a diffusion region. We observe a high degree of light sensitivity of the electric current through the film thickness for one polarity of an applied voltage. For the other polarity, the current is not affected by the light. We explain the observed phenomenology using the single-particle model based on the existence of interface states on the metal-oxide interfaces.
文摘We map the requirements and design rules for dielectric materials that target large scale energy storage applications of electrostatic capacitors. The molecular unit (dielectrophore) must contain three main components: a polarizable subunit having large electric dipole, an isolating subunit which prevents current leakage, and a structural element that promotes self-assembly of molecules in solution and in mesophase and promotes crystallization in the process of film formation. This structural subunit is necessary for high molecular density and enhanced resistivity of film. The process engineering steps required for the supramolecular assembly and crystal film formation (cascade crystallization) are addressed.
文摘Main design principles of the potent rylene-based class of dielectrophores are established in the present article. The proposed class of dielectrophores comprises polarizable aromatic core, conjugated with aromatic subunits, and bears resistive groups on the periphery. The aromatic subunits might comprise donor and acceptor groups for the desired level of polarizability of the molecule. Appropriate positions for donor and acceptor groups are established by quantum chemistry modeling. The design principles are demonstrated on the molecular design of an efficient rylene-based dielectrophore.
文摘We experimentally demonstrate and numerically analyze large arrays of whispering gallery resonators.Using fluorescent mapping,we measure the spatial distribution of the cavity ensemble’s resonances,revealing that light reaches distant resonators in various ways,including while passing through dark gaps,resonator groups,or resonator lines.Energy spatially decays exponentially in the cavities.Our practically infinite periodic array of resonators,with a quality factor(Q)exceeding 107,might impact a new type of photonic ensembles for nonlinear optics and lasers using our cavity continuum that is distributed,while having high-Q resonators as unit cells.