Abstract: The photovoltaic devices with free electrons of nanometal were studied by nanometal scattering and near-field surface plasmon resonance (SPR) enhancing. The results revealed that devices with metal nonoparticles can improve the photoelectric conversion efficiency of solar cells. The metal nanoparticles roughness also reduced the incident light reflection and increased the electrical conductivity of metal characteristics.
Abstract: We investigated the nanoscale thermal bubble nucleation based on the principle of Coulter counter. With micro-nanofabrication technologies, a device was designed and fabricated, and a detection platform was set up which was used to investigate the thermal bubble nucleation of aqueous solution confined in a nanochannel with a cross size of about 100 nm×100 nm. Results show that with the temperature of the solution confined in the nanochannel increasing, the current through the channel increases first and then decreases, and vanishes after a fluctuating period. It can be found that the generating thermal bubbles can hinder the current flowing through the nanochannel. In addition, the shrinking and expanding of thermal bubbles’ volume correspond to the increase and decrease of the current. Finally, the thermal bubbles block the nanochannel entirely. Through the experiment results, our device can be applied to investigate the complex behaviors of thermal bubble produced in aqueous solution confined in nanochannels, effectively.
Abstract: Highly ordered mesoporous silica nanofibers with no core/sheath structure were prepared by coaxial electrospinning combined with the solvent evaporation induced surfactant assembly process. The mesoporous structures have been proved and the effect of different cosurfactants on pore sizes of mesoporous silica nanofibers has been investigated.
Abstract: A nanoindentation technique with a spherical indenter of tip radius 10 μm is applied to the evaluation of stress-strain curve at a local area of a pure iron under the uniaxial compressive stress exerted through the iron, and the influence of the compressive stress on the estimated stress-strain curve has been examined. A continuous multiple loading method is employed to determine the stress-strain curve. In the method, a set of 21 times of loading/unloading sequences with increasing terminal load are made and load-displacement curves with the different terminal loads from 0.1 mN to 100 mN are then continuously obtained and converted to a stress-strain curve. To examine the stress dependence of the stress-strain curve, the estimation by the nanoindentetion is performed under different uniaxial compressive stresses up to 250 MPa. It has been found that the stress-strain curve determined by the nanoindentation shifts upward as the compressive stress increases and the quantity of the shift is almost equal to the uniaxial stress acting on the iron specimen. It is also noted that the yield stress (0.2 % proof stress) estimated from the stress-strain curve increases almost proportionally to the uniaxial stress and the increase ratio tends to decrease as the stress reaches around 200 MPa.
Abstract: Graphene-based composites now has been payed more and more attention to because it can make up many shortcomings of the pure single-layer graphene.In many papers ,there are one same phenomenon said that graphene can not be well dispersed in matrix since it’s high specific surface area and high surface energy.In this work,we reported the preparation of ZnO/graphene nanocomposites through the way of situ-reaction in the surface of graphite oxide.Then,the nanocomposites were characterized by X-ray diffraction (XRD), Fourier Transform-Infared spectroscopy (FTIR),transmission electron microscopy (TEM), and thermogravimetry (TG). The results indicated that the graphene oxide had been reduced by hydrazine hydrate and the ZnO crystal attached to the surface of graphene well.The ZnO/graphene nanocomposites can be expected to be dispersed in some kinds of rubber to improve their electric and thermal conductivities in the following experiments.
Abstract: Adjusting the proportion of gases and stirring rate and other parameters, the value of pH, electrical conductivity, electrode potential, temperature of the system were tested online under different parameters. According to the results of scanning electron microscopy , the coating effect of different reaction stages and the influence of different coating processes were analyzed.
Abstract: Poly (butylene succinate)/titanium dioxide nanocomposite was prepared by melt blending in a HAAKE mixer. The degradation was studied under ultraviolet aging conditions. The SEM results showed that there were not any visible pores in the nanocomposite surface, which indicated that the addition of TiO2 could resist the ultraviolet degradation in some degree. The FT-IR results presented that the neat PBS and 1 wt% PBS/TiO2 nanocomposite had an overall increased peak intensities, especially for the carbonyl group. The intensities of neat PBS after 72h ultraviolet aging were increased significant than that of the 1 wt% PBS/TiO2 nanocomposite. FT-IR results further confirmed the SEM results and revealed the mechanism of the PBS degradation under ultraviolet aging conditions.
Abstract: Many electronic applications of carbon nanotubes crucially rely on techniques of selectively producing either semiconducting or metallic CNTs, preferably of certain chirality. Several methods of separating semiconducting and metallic CNTs are known, but most of them are not yet suitable for large-scale technological processes. The most efficient method relies on density-gradient ultracentrifugation, which separates surfactant-wrapped nanotubes by the minute difference in their density. This density difference often translates into difference in the nanotube diameter and (semi) conducting properties. Another method of separation uses a sequence of freezing, thawing, and compression of SWNTs embedded in agarose gel.
Abstract: In this paper, the dispersion of carbon nanotubes (CNTs) in cement matrix was analyzed by Three-dimensional Monte Carlo Simulation. A Hard core model was employed which was not allow the intersection among CNTs in a simulated three-dimensional representative volume element (3-D RVE). The position and the orientation of CNTs were assumed to follow the uniformly random distribution. The results showed that CNTs were dispersed randomly and it was helpful for the further simulation calculation about mechanical, conductivity and piezoresistivity properties.