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CaSn(OH)(6) nanotubes were fabricated by sonochemical precipitation method at room temperature. A direct rolling process from nanosheets to nanotubes was expected for the synthesis of CaSn(OH)(6) nanotubes. The transient CaSn(OH)(6) nanosheets are formed as intermediates produced by the spontaneous self-assembly and transformation of amorphous colloid clusters. During the crystallization process of intermediate nanosheets, the relaxation of surface strain in the nanosheet interfaces can induce the nanosheets to roll up to form nanotubes under ultrasonic conditions. In this synthesis, the addition of Na(2)CO(3) seems to play an important role in the formation, size, and shape control of the nanotubes. Investigations into the stability performance of the nanotubes indicate that the morphologies are very sensitive to pH and temperature. The method suggests a general strategy for the design and fabrication of functional single-crystalline nanotubes through an intermediate nanosheet rolling process. The in vitro fabrication of such single crystal nanotubes could shed light on fundamental mechanisms for closed hollow nanostructures. Furthermore, nanotubes produced in high yield and at low cost are envisioned to have applications in areas ranging from medicine to pharmaceuticals through to materials science.

ZnO/CdSe core-shell nanorod array films were synthesized via a two-step method. ZnO nanorod array films were first grown on a TCO substrate, and then CdSe nanocrystals were deposited on the nanorods to form core-shell structured films. The resulting films were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV–vis absorption spectroscopy. Especially, dark-field images and transmission electron diffraction of the TEM were used to study the morphology and the chemical nanostructure of the ZnO/CdSe core-shell nanorods in detail. We investigated the photovoltaic performance of the resulting ZnO/CdSe core-shell nanorod array films as solar cell photoanodes. Parameters, such as the length of the ZnO nanorods, the shell phase structure and the deposition time of the CdSe nanocrystals were found to affect the photovoltaic performance of the solar cell. This study provides a facile method to prepare nanocomposite photoanodes of solar cells, and gives some insight about the fundamental mechanisms that improve the performance.

In the present work, we report for the first time an investigation on anodic oxidation of tin in an electrolyte of dimethyl sulfoxide (DMSO)/water mixtures containing citric acid in the trans-passive region. The anodization leads to the formation of flowerlike patterns composed of tin citrate complex nanostrips on tin substrates. The products were characterized using XRD, SEM, TEM, FTIR, and XPS measurements. The formation mechanism of the tin citrate complex microstructures is discussed and the influences of the voltage, citric acid concentration, and electrolyte composition on the morphology of the microstructures were investigated. The nanostrips with a smooth surface can be transformed to polycrystalline SnO2 nanostrips with a porous structure by a thermal annealing process. This work developed a simple, clean, and effective route for fabrication of large area SnO2 nanostructured films.

Uniform crystalline MgSn(OH) 6 nanocubes were synthesized by a hydrothermal method. The influences of reaction conditions were investigated and the results showed that the solvent constituents significantly affected the shape and size of MgSn(OH) 6 ·SnO 2 /Mg 2 SnO 4 has been obtained by thermal treatment at 850 °C for 8 h under a nitrogen atmosphere using MgSn(OH) 6 as the precursor. The electrochemical tests of SnO 2 /Mg 2 SnO 4 revealed that SnO 2 /Mg 2 SnO 4 has a higher capacity and better cyclability compared to pure SnO 2 or Mg 2 SnO 4 . The electrochemical performance of SnO 2 /Mg 2 SnO 4 was sensitive to the size of the nanoparticles. The lithium-driven structural and morphological changes of the electrode after cycling were also studied by the ex-situ XRD pattern and TEM tests. This work indicates that SnO 2 /Mg 2 SnO 4 is a promising anode material candidate for application in Li-ion batteries.

Nickel hydroxyl sulfate (Ni(SO4)0.3(OH)1.4) nanobelts were obtained via a simple template-free hydrothermal reaction. The structural evolution of Ni(SO4)0.3(OH)1.4 nanobelts during ex situ heat treatment and in situ electron irradiation are investigated using transmission electron microscopy (TEM) techniques mainly including bright-field imaging, selected-area electron diffraction combined with kinematic simulations, and high-resolution TEM. The transformation from Ni(SO4)0.3(OH)1.4 to NiO can be observed in both ex situ and in situ experiments. Based on the TEM results, the structural evolution is clarified and the preliminary structural framework of Ni(SO4)0.3(OH)1.4 is proposed. This structural evolution also provides an excellent approach for large-scale production and/or modification of NiO nanoparticles.

FeS and FeS2 nanosheet films were selectively synthesized on iron substrates through one-step hydrothermal treatment of iron foil and sulfur powder in the presence or absence of hydrazine. The resulting FeSx (x = 1, 2) nanosheet films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) and used as novel photocathodes in tandem solar cells with dye-sensitized TiO2 nanorod films as the corresponding photoanode. The photovoltaic properties of the tandem dye-sensitized solar cells were carefully studied. We found that the performance of the FeS nanosheet film photocathode was better than that of the FeS2 one in the tandem dye-sensitized solar cells. In the case of the FeS nanosheet film photocathode, a short circuit photocurrent (Isc) of 2.53 mA/cm2, an open circuit photovoltage (Voc) of 0.60 V, a fill factor (FF) of 0.31, and conversion efficiency (η) of 1.32% were obtained under an illumination of 100 mW/cm2. This study suggests that ...

Low-dimensional single-crystalline CdCO3 nanostructures such as nanowires, nanobelts, nanorolls, and one-dimensional (1D) hierarchical structures have been synthesized through a convenient, low-temperature hydrothermal method, and the products have been characterized by X-ray diffraction, transmission electron microscopy, field emission scanning electron microscopy, and selected area electronic diffraction. The influences of ammonia concentration, reaction time, and temperature on the morphologies of CdCO3 have been investigated. In addition, these low-dimensional nanostructures can be transformed into oriented CdO nanoporous structures through heat treatment processing, and the corresponding shapes can be preserved completely.

Objective To compare the wear of conventional ultra-high molecular weight polyethylene (CUHMWPE) and highly cross-linked polyethylene (HCLPE) in hip revision with liner exchange fixed with original locking mechanism using analysis of history medical data. Methods From Jan. 1, 2000, to Dec. 31, 2007, 26 patients (with 29 involved hips) underwent liner exchange revision fixed with the original locking mechanism due to wear of CUHMWPE and/or osteolysis. The mean age was 53 ± 9 years at the time of the primary total hip arthroplasty (THA) and 64 ± 9 years at the revision. The exchanged liners (Marathon, Depuy) were made of HCLPE. Annual X-rays were used to measure linear wear and osteolysis. The annual linear penetration was measured using PolyWare® software (Draftware Inc.). Annual Harris Hip Scores(HSS) were recorded. Results The mean follow-up time between the primary and revision THAs was 11 ± 2 years and 8 ± 2 years after revision. The mean Harris Hip Score(HHS) before primary THA, 1 year after primary THA, before revision and 1 year after revision was 43±5, 85±5, 71±6, 83±7 individually. The mean penetration of the CUHMWPE and HCLPE liners occurring in the first year were 0.44 ± 0.28 mm and 0.38 ± 0.14 mm, respectively (p = 0.211). The mean annual linear penetration of CUHMWPE and HCLPE from the second year onward were 0.29±0.09 mm and 0.08 ± 0.03 mm respectively (p

ZnO nanoparticles which have diameter of 15 nm were prepared by hydrothermal method. ZnO nanosheets were obtained by rehydrothermal treatment of ZnO nanoparticles. The phase and morphology were investigated by using transmission electron microscope, scanning electron microscope and X-ray diffraction. Also, absorbance spectra were measured by using a UV–vis spectrophotometer. A fill factor of 0.55, short-circuit current of 2.059 mA/cm 2 , open-circuit voltage of 0.593 V and an overall light to electricity conversion efficiency of 1.55% for the solar cell based on ZnO nanosheets were obtained. r 2007 Elsevier B.V. All rights reserved.

Novel nanocrystalline TiO 2 films with the textural channels are obtained for dye-sensitized solar cells (DSSCs). The textural channels consisting of the cracks on the surface and the nanopores with average diameter of about 41 nm are produced by packaging ZnO nanowires with diameter of 30–50 nm into TiO 2 films and subsequently etching ZnO nanowires by hydrochloric acid. The performances of DSSCs based on novel TiO 2 films (with the textural channels) and traditional TiO 2 films (without the textural channels) are investigated, respectively. When two kinds of typical quasi-solid-state electrolytes and one kind of solid-state electrolyte are used, the energy conversion efficiencies of DSSCs from novel TiO 2 films are improved by 20–30% compared to that from traditional TiO 2 films. The reasons for the great improvement are investigated chiefly by UV–vis absorption spectra, field emission-scanning electron microscope (FE-SEM) and electrochemical impedance spectroscopy (EIS) technique. The results show that the introduction of the textural channels facilitates better penetration of quasi-solid/solid-state electrolytes into the nanopores of novel TiO 2 films and thus results in better interfacial/electrical contact and faster interfacial reaction.

For the first time nanoporous Zn and Ni particles were synthesized in dimethyl sulphoxide (DMSO) by a sonoelectrochemical method. The as-prepared samples were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen sorption. It was found that these nanopores were produced by the aggregation and/or melting of primary nanoparticles of about 4–5 nm in size under ultrasound irradiation after electrochemical reduction of metal ions. The utilization of nonaqueous solvent prevented the oxidation of these active metal nanoparticles, while the presence of poly-(vinylpyrrolidone) could inhibit the growth of the nanoparticles. This study provides a general method to continuously prepare nanoporous active metal particles from inorganic metal salts with high yields.

Luminescence of the short multiwalled carbon nanotubes (MWNTs) conjugated with carboxylic acid groups has been studied. The results show that the carboxyl-functionalized short MWNTs could emit luminescence and the emission peak appears at 500 nm with a corresponding optimal excitation wavelength centering at 310 nm. When the short MWNTs are filtered through 0.15 μm polytetrafluoroethylene (PTFE) membrane, the ultrashort MWNTs are obtained from the filtrate. An interesting feature for the ultrashort MWNTs is that the emission intensity is strengthened and the peak is slightly blue shifted to 460 nm. This result indicates that the luminescence properties of MWNTs are strongly affected by the tube length. After chemical oxidization cutting, defects and carboxylic acid groups at the tube end and/or sidewall can be produced; the more shorten of MWNTs, the better dispersion and carboxylic passivation of the nanotubes, and the more intense luminescence emissions. The broad emissions are logically attributed to the trapping of excitation energy by defect sites in the carboxyl-functionalized nanotube structure.

In this paper, we prepared TiO2@CdS core–shell nanorods films electrodes using a simple and low-cost chemical bath deposition method. The core–shell nanorods films electrodes were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and UV–vis spectrometry techniques. After applying these TiO2@CdS core–shell nanorods electrodes in photovoltaic cells, we found that the photocurrent was dramatically enhanced, comparing with those of bare TiO2 nanorods and CdS films electrodes. Moreover, TiO2@CdS core–shell nanorods film electrode showed better cell performance than CdS nanoparticles deposited TiO2 nanoparticles (P25) film electrode. A photocurrent of 1.31 mA/cm2, a fill factor of 0.43, an open circuit photovoltage of 0.44 V, and a conversion efficiency of 0.8% were obtained under an illumination of 32 mW/cm2, when the CdS nanoparticles deposited on TiO2 nanorods film for about 20 min. The maximum quantum efficiency of 5.0% was obtained at an incident wavelength of 500 nm. We believe that TiO2@CdS core–shell heterostructured nanorods are excellent candidates for studying some fundamental aspects on charge separation and transfer in the fields of photovoltaic cells and photocatalysis. Keywords: Core–shell, CdS, TiO2, Nanorods, Photoelectrochemical property

In this paper, large-scale, single-crystalline ZnO nanotube arrays were directly fabricated onto F-doped SnO2 (TCO) glass substrate via an electrochemical deposition method from an aqueous solution for the first time. The tubes had a preferential orientation along the [0001] direction and hexagon-shaped cross sections. The novel nanostructure could be easily fabricated without a prepared layer of seeds on the substrate. The surface condition of substrate material and the experimental conditions played a key role in the nanotube formation. A possible formation mechanism has been proposed. Keywords: ZnO nanotube, Arrays, TCO glass, Electrochemical deposition

Antimony-doped tin oxide (ATO) suspension with monodispersion has been directly synthesized by hydrothermal method by using mixed Sb/Sn hydroxide solution as precursor, and temperature control has been used during the crystal growth. The ATO particles were characterized by XRD, TEM, SEM–EDS and resistance test. X-ray diffraction shows that all Sb ions come into the SnO 2 lattice to substitute Sn ions. The crystallinity and doping of Sb are improved through stage heating, compared with that at constantly high temperature. TEM and SEM images indicate the ATO nanoparticles are monodispersed with the size ranging from 10 to 15 nm. The process of stage heating can enhance Sb doped level and realize the synthesis of monodispersed doped oxide particles under low temperature in a short time. The possible growth mechanism is proposed.

Electrodeposition of nanoporous ZnO films and their applications to dye-sensitized solar cells (DSSCs) were investigated in the aim of developing cost-effective alternative synthetic methods and improving the ZnO-based DSSCs performance. ZnO films were grown by cathodic electrodeposition from an aqueous zinc nitrate solution containing polyvinylpyrrolidone (PVP) surfactant. PVP concentration had strong effects on the grain sizes and surface morphologies of ZnO films. Nanoporous ZnO film with grain size of 20–40 nm was obtained in the electrolyte containing 4 g/L PVP. The X-ray diffraction pattern showed that nanoporous ZnO films had a hexagonal wurtzite structure. Optical properties of such films were studied and the results indicated that the films had a band gap of 3.3 eV. DSSCs were fabricated from nanoporous ZnO films and the cell performance could be greatly improved with the increase of ZnO film thickness. The highest solar-to-electric energy conversion efficiency of 5.08% was obtained by using the electrodeposited double-layer ZnO films (8 μm thick nanoporous ZnO films on a 200 nm thick compact nanocrystalline ZnO film). The performance of such cell surpassed levels attained in previous studies on ZnO film-based DSSCs and was among the highest for DSSCs containing electrodeposited film components.

In this paper, we prepared the nanocrystalline CdS films on the indium-doped tin oxide (ITO) glass substrates using a doctor-blade technique. The source CdS powder was first prepared by a hydrothermal method and then ground into a screen-printing paste by adding ethyl cellulose as a binder and terpineol as a solvent. The CdS samples were characterized by XRD, SEM, TEM, and UV–Vis diffuse reflectance spectroscopy. A photocurrent of 3.51 mA/cm2, a fill factor of 0.44, an open circuit photovoltage of 0.50 V, and a conversion efficiency of 2.2% were obtained under a simulated solar illumination of 35 mW/cm2, when the CdS film was annealed at 380 °C in air for 30 min. The maximum quantum efficiency of 5.5% was obtained at an incident wavelength of 500 nm. Our method provides a general way to prepare electrodes of metal chalcogenide nanocrystalline films. Keywords: CdS, Doctor-blade, Hydrothermal, Nanoparticles, Photoelectrochemical property

The adsorption of nicotine and tar from the mainstream smoke (MS) by the filter tips filled respectively with oxidized carbon nanotubes (O-CNTs), activated carbon and zeolite (NaY) has been investigated. O-CNTs show exceptional removal efficiency and their adsorption mechanism is investigated. Capillary condensation of some ingredients from MS in the inner hole of O-CNTs is observed and may be the primary reason for their superior removal efficiency. The effect of O-CNTs mass on the removal efficiencies is also studied and the results show that about 20–30 mg O-CNTs per cigarette can effectively remove most of nicotine and tar.

This paper introduces the preparation of needle-shaped cuprous oxide (Cu2O) particles 3–10 nm in diameter and 40–150 nm in length on multiwall carbon nanotubes (MWNTs) by anodic oxidation of copper electrode in alkaline solution. Steady-state concentration of H2O2 as high as 0.42 mM is produced in aqueous suspension of nanosized Cu2O/MWNTs composites illuminated by simulated solar light in the presence of formate and oxygen. Assisted by Fe2+-EDTA, these photogenerated H2O2 can be used as Fenton reagent; hydroxyl radicals have been detected indirectly. The results for the degradation of brilliant red dye indicate that the effect of this new Fenton system (1 g/L nanosized Cu2O/MWNTs composites + Fe2+-EDTA + simulated sun light) can approach that of traditional Fenton system (4 mmol/L H2O2 + Fe2+-EDTA). This system is superior to the classical Fenton system in that it can act effectively for a long time.

This paper investigates electrochemical behavior of ZnO thin films deposition on transparent conducting optically glass from a simple aqueous zinc nitrate solution. At low temperature, ZnO films with grain sizes between 10 and 15 nm are obtained by controlling growth rate. The X-ray diffraction pattern shows that ZnO film has a hexagonal wurtzite structure and the preferred growth orientation is the (002) direction. Detailed X-ray photoelectron spectroscopy analysis indicates the presence of metallic Zn, OH and H 2 O species in the as prepared ZnO films. In addition, ZnO thin film changes from Zn-rich to O-rich after being annealed in air. Optical characterizations show that the films as prepared and annealed at 250 °C have high optical transmittance (> 90%) in the visible wavelength range and the band gap of the nanocrystalline ZnO films is 3.37 eV.

The grain size in cuprous oxide (Cu 2 O) thin films is a key to improve the performance of solar application devices. In this paper, electrochemical deposition of nanocrystalline Cu 2 O thin films on TiO 2 films coated on transparent conducting optically (TCO) glass substrates by cathodic reduction of cupric acetate has been investigated. The deposition kinetics of nanocrystalline Cu 2 O thin films were studied and the parameters limiting the deposition of the films were determined. Pure Cu 2 O deposited at bath temperature between 0 and 30 °C produced spherically shaped grains with 40∼50 nm diameters which have not been reported previously. The effect of pH was studied and a solution with a pH between 5.5 and 6 was found to be best. The effect of annealing on bulk structure, electrical resistivity, and optical absorption of nanocrystalline Cu 2 O thin films was also studied and the results were discussed.

A way to prepare nano-size Cu2O with electrochemical method was first reported. The nano-size TiO2–Cu2O particle composites were obtained by an electrochemical method and the properties of the composites were evaluated by high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and diffuse reflectance UV–Vis spectroscopy (UV-DRS). The photocatalytic activities of the composites prepared by this method exceed that of Degussa P-25. Keywords: Nano-size TiO2–Cu2O particle composites, Electrochemical method, High resolution transmission electron microscopy, X-ray photoelectron spectroscopy, Diffuse reflectance UV–Vis spectroscopy

The electron irradiation effect on 80/20 poly(vinylidene fluoride–trifluoroethylene) [P(VDF–TrFE)] copolymers was studied by FTIR spectra and X-ray diffraction. Infrared spectra showed decreasing intensity of bands at 1430, 1286, 846, and 505 cm−1, the appearance and intensity increasing with irradiation doses of bands at 768, 601, and 1735 cm−1, which revealed the conformational change after irradiation. The X-ray diffraction patterns exhibited a decrease of volume fraction of ferroelectric phase and expansion of the lattice space. The electron-irradiated P(VDF–TrFE) films showed structural changes and polar phase to nonpolar phase transformation. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2903–2907, 2004

The reversible transformations between the metastable paraelectric phase induced in irradiation and polar ferroelectric phase (FEP) during both applied external field and thermal cycling process, were observed experimentally. The transition induced by thermal is interpreted by the ferroelectric theory of first-order transition, and the other one induced by electric field is explained by Landau–Devonshire phase transition theory. It is useful to elucidate the microscopic mechanism involved, and this might also be the most possible microscopic interpretation for large electrostrictive strain in these copolymers.

The blend system containing a poly(vinylidene fluoride/trifluoroethylene) [P(VDF/TrFE)] copolymer (68/32 mol %) and poly(vinyl acetate) (PVAc) was miscible from the results of differential scanning calorimetry (DSC) studies that exhibit the presence of a single, composition-dependent glass transition temperature (T g ) and a strong melting point depression for the semicrystalline P(VDF/TrFE) component. However, differences between the DSC and dielectric measurements, which showed a separate P(VDF/TrFE) T g peak, suggests that the P(VDF/TrFE)/PVAc blends are actually partially miscible. Because of the lower dielectric constant of PVAc and the reduced sample crystallinity caused by the addition of PVAc, both the dielectric constant and the remanent polarization of the copolymer blends decrease with increasing PVAc content. The presence of a small amount of PVAc stabilized the anomalous ferroelectric behavior of ice-water-quenched P(VDF/TrFE), and the blend portrayed normal polarization reversal behavior after adding only 1 wt % PVAc. The piezoelectric response suggests small changes with an increasing number of poling cycles. It is believed that PVAc affects the D-E hysteresis behavior at the interface between crystalline and amorphous phases, although much work remains to be done to confirm this hypothesis.

Although the biodegradation of polyurethanes (PU) by oxidative and hydrolytic agents has been studied extensively, few investigations have reported on the combination of their effects. Since neutrophils (PMN) arrive at an implanted device first and release HOCl, followed by monocyte-derived macrophages (MDM) which have potent esterase activities and oxidants of their own, the combined effect of oxidative and hydrolytic degradation on radiolabeled polycarbonate-polyurethanes (PCNU)s was investigated and compared to that of a polyester-PU (PESU) and a polyether-PU (PEU). The PCNUs were synthesized with PCN (MW = 1,000), and butanediol (14C-BD) and one of two diisocyanates, hexane-1,6-diisocyanate (14C-HDI) or methylene bis-p-phenyl diisocyanate (MDI). The PESU and PEU were synthesized using toluene-diisocyanate (14C-TDI), with polycaprolactone and polytetramethylene oxide as soft segments respectively, and ethylene diamine as the chain extender. The effect of pre-treatment with 0.1 mM HOC1 for 1 week on the HDI-based PCNUs and both TDI-based PUs resulted in a significant inhibition of radiolabel release (RR) elicited by cholesterol esterase (CE), when compared to buffer alone, whereas the MDI-based PCNU showed a small but significant increase. When PMN were activated on the HDI-based PCNU surface with phorbol myristate acetate (PMA), HOCl was released for 3 h, and was almost completely abolished by sodium azide (AZ). Simultaneously, the PMN-elicited RR, shown previously to be due to the esterolytic cleavage by serine proteases, was inhibited approximately 75% by PMA-activation of the cells, but significantly increased relative to the latter when AZ was added. Both in vitro oxidation by HOCl and the release of HOCI by PMN were associated with the inhibition of RR and suggest perturbations between oxidative and hydrolytic mechanisms of biodegradation.

The Au nanoparticle sandwich double spheric-shells of SiO2@Au@TiO2 (SAT) microspheres are synthesized. The significant influence of the SAT microspheres on the properties of dye-sensitized solar cells (DSSCs) is investigated. Studies indicate that the introduction of SAT markedly enhanced the light scattering and capture ability of DSSCs and thus photogenerated electrons. DSSCs doped with 2.25 wt% SAT exhibit a maximum short circuit current density of 17.0 mA cm-2 and photoelectric conversion efficiency of 7.14%, which are remarkably higher than those of conventional DSSCs at 15.7% and 21.2%, respectively. The marked enhancement in the performance of the optimal DSSCs can be attributed to the synergetic complementary effect of the enhanced light scattering of the microspheres and to the localized surface plasmon resonance of the Au nanoparticles in the SAT, and is a novel promising way of enhancing the performance of DSSCs.

Mo-based binary oxides (MBOs) and Mo-based ternary oxides (MTOs) are a research focus because of their widespread applications. The traditional synthesis routes for MBOs and MTOs require high temperature and are time intense. Here, a rapid, facile, and scalable strategy to efficiently fabricate MBOs and MTOs with various morphologies and crystal structures is reported. Only 1 min is required for the whole process and the yield is above 90%. This strategy is the simplest and the fastest method reported and exhibits large potential for application. Furthermore, the as-synthesized HxMoO3 nanobelts and NiMoO4·xH2O nanowires display a specific capacitance of 660.3 F g−1 at 2 mV s−1 and a specific capacity of 549 C g−1 at 1 A g−1. In addition, to assemble the HxMoO3 and NiMoO4·xH2O electrodes together, the solid state hybrid electrolyte is employed to take advantage of MBOs and MTOs. The obtained NiMoO4·xH2O//HxMoO3 device delivers a specific capacitance of 156 F g−1 at 0.8 A g−1 and an energy density of 55.6 Wh kg−1 at a power density of 640 W kg−1, making it attractive for application as an energy storage material.

A novel carbon-CoO-NiO-NiCo2O4 integrated electrode has been designed by reducing the hetero-structured NiCo2O4 nanosheet array with C2H2 on the nickel foam at a low temperature of 350 °C. The topotactical transformation from NiCo2O4 to the integrated electrode has been first conceived and investigated. Such unique nanoarchitectures exhibit excellent electrochemical performance with ultrahigh capacitance and desirable cycle life at high rates.

The γ-ray irradiation effect on poly(vinylidene–trifluoroethylene) 80/20 mol% copolymers was studied. It is found that the irradiation results in the cross-linking in the amorphous area and the carbon–carbon double bond in the copolymer due to dehydrofluorination. The thermal analysis (DTA) data indicate that the irradiation down shifts both the melting temperature and the phase transition temperature, and the irradiation also reduces the crystallinity. It is found that the size of the crystal regions in the copolymer decreases during the irradiation and that the lattice space expanses with the irradiation. The crystal regions with a reduced size might response for the excellent electromechanical properties observed in the irradiated copolymer.

A high-performance supercapacitor electrode is designed and fabricated with the 3D interconnected continuous nanoporous Co/CoO core-shell hybrid nanostructure grown on nickel foam. The Co/CoO core-shell hybrid nanostructures are obtained via a hydrothermal method, followed by high-temperature annealing in hydrogen atmosphere, and finally placed in air at 50 °C for 1 h. The Co/CoO core-shell nanostructure assembled by a conductive metal-core and a CoO shell, brings low resistance, high specific capacitance of 5.632 F cm-2 and good capability stability (81.5% capacitance retention after 6000 cycles). An asymmetric supercapacitor device built by the Co/CoO (positive electrode) and activated carbon (negative electrode) can deliver a working voltage of 1.7 V and display a high energy density of 0.002 67 Wh cm-2 at a power density of 0.001 62 W cm-2, which is far superior to that of a supercapacitor at a similar power density.

Cooperative relaying technology among secondary users (SUs) in cognitive radio networks (CRN) is shown to yield a significant performance improvement, such as improving spectrum utilization as well as system fairness in CRN. This paper investigates the problem of the relay selection and resource allocation in a downlink OFDMA cognitive relay network. The objective of this optimization problem is to maximize both system throughput and system fairness, which is achieved through our proposed non-transferable utility coalition graph game algorithm (NTU-CGGA). In this algorithm, the SUs with more available channels can help SUs with less available channels to improve their utility in terms of the throughput and fairness by forming a directed tree graph. The coalition graph is formatted according to spectrum availability and traffic demands of SUs by using merge-split rule. So it can effectively exploit both space and frequency diversity of the system. Simulation results show that, NTU-CGGA significantly improves system throughput while not reducing the fairness level, which has a better performance comparing with other existing algorithms.

The shooting and bouncing ray (SBR) method is well known for providing more accurate results by including the scattering effect arising from multiple bounces. The fact that the fields tracking in the SBR method is calculated by only a geometrical optics (GO) approximation makes the choice of the exit aperture matter. In this paper, a comprehensive study is made on the exit aperture in the SBR method. Three kinds of exit aperture are compared, i.e., bounding box of the cavity, wavefront of the ray tube and the scatterer itself. Numerical simulations with the exit aperture of different kinds are conducted to verify the theoretical analysis and to draw some conclusions.

The technology of detection and reconstruction for valid information is a research emphasis in TMPEST, the technology of electromagnetic leaking research. After the research and analysis of computer video leaking in CRT system, the problem of weak signal extraction in receiving part of computer video leaking measurement system is pointed out. The extraction method for horizontal synchronization signals based on the correlation technique and de-noising method for video leaking signals based on the one-dimensional wavelet transform are proposed, which are of great importance in detecting and reconstruction of video leaking signal.

A novel two-step technique is introduced to synthesize BaSn(OH)6nanorods. The method involves the preparation of precursor Na2Sn(OH)6crystals in aqueous solution via hydrothermal method and the ion-exchange reaction between Na2Sn(OH)6crystals and Ba2+solution that followed, assisted by ultrasonic treatment. The BaSn(OH)6nanorods array are formed due to the split of plate-formed Na2Sn(OH)6during the ion-exchange treatment. The influence of the surfactant on the growth of the one-dimensional (1D) BaSn(OH)6nanostructures is investigated. In addition, the powder BaSnO3has been obtained by thermal treatment at 450°C for 5 h under inert gas protecting condition using BaSn(OH)6nanorods as precursor. The 1D shape of BaSn(OH)6was retained after thermal treatment.

Nanobelts of nickel hydroxyl sulfate have been prepared on a large scale via a simple template-free hydrothermal reaction on the basis of a complex [Ni(NH(3))(6)](2+) formed with Ni(2+) and ammonia in an ethanol-water solution. The as-synthesized nanobelts were single crystals, with several tens of microns in length and 50-150 nm in width. The nanobelts were enclosed by top surfaces (100) and side surfaces (001) and their growth direction was parallel to [010]. The function of aqueous ammonia and ethanol was discussed. Furthermore, nanostructures of a mixture of crystralline NiO and amorphous nickel sulfate with various morphologies, such as nanobelts, porous nanobelts, and nanoparticles, were obtained by the thermal treatment of the as-synthesized Ni(SO(4))(0.3)(OH)(1.4) nanobelts at different temperatures.

Image enhancement can improve the perception of information. An image taken from a real scene can be divided into several regions according to the need for enhancement. One particular enhancement method improves some regions and actually deteriorates the other regions which have no need for such enhancement or any enhancement at all. This paper proposes a method to improve the enhancement result with image fusion method with evaluation on sharpness. Several different evaluation methods and fusion policies are discussed and compared. The experiment results show that the fusion improves the enhancement results.

Catalytic activity of cuprous oxide (Cu2O) micro-particles with cubic, octahedral, truncated-octahedral and hollow opened sphere structures for thermal decomposition of ammonium perchlorate (AP) was investigated in this paper. Cu2O with different morphologies were synthesized through one-pot hydrothermal method, which is based on the reduction of Cu(II) with d -(+)-glucose in an alkalic solvent. Morphology, crystal structure and specific surface area of final samples were characterized by using SEM, XRD, and BET, respectively. TG/DTA results show that the samples with different morphologies exhibit quite different catalytic activity in different stage of thermal decomposition of AP. Through comparing them, Cu2O micro-octahedrons with {1 1 1} facets show better catalytic effect than cubes with only {1 0 0} facets, while the Cu2O hollow microspheres enhance the high-temperature exothermic decomposition of AP significantly. The authors also discussed some underlying catalytic mechanism and offered some selection basis of catalysts in the thermal decomposition of AP.

Nowadays in the field of communication,leaky coaxial cables (LCX) are widely used and their performances always determine the capability of a whole communication system.Considering the testing characteristics of LCX,the proposed testing system is designed based on LabVIEW,a developing tool of virtual instrument. With the help of DAQ module and GPIB technology, the hardware part with high efficiency is used to acquire the testing characteristics of LCX such as coupling loss etc.Furthermore considering the tolerance caused by either test site or test equipment,the system also offers correcting compensation to improve the accuracy of the test result.The software offers a user-friendly interface,which provides both data management and data analyses for LCX samples.

Medical endoscope system has the characteristics as high precision, functional flexibility and cost efficiency, which make it the assistant of medical diagnoses as well as the foundation of long-distance transmission of medical images and information and real-time dynamic image processing. Nevertheless, distortion of medical image such as fuzzy key details of organs may appear caused by the interlacing scanning technology, which may result in misdiagnoses. De-interlacing technique to eliminate distortion is essential. The statement of image interlacing distortion is presented through the theory of interlacing scanning technology at first. And then various de-interlacing algorithms are proposed and compared. Finally, according to the major reason of image interlacing distortion in medical endoscope system, adaptive de-interlacing algorithm is used to eliminate the distortion with.

Electrical field-induced strain response of electron-irradiated poly(vinylidene fluoride-trifluoroethylene) copolymer has been studied by a Mach–Zehnder type heterodyne interferometer in the frequency range of 3–9 kHz. The electrostrictive constant is calculated from the strain results, which is of the same order of magnitude as those obtained at 1 Hz by a bimorph-based strain sensor but at much lower electrical field. Changes in the dielectric property, phase transition behavior and crystal structure of the same copolymer have also been studied. The reversible solid–state transition between the polar and nonpolar phase in the crystalline regions of the copolymer driven by the external electric field is suggested to be responsible for the significant high electrostrictive strain of the electron-irradiated copolymer.

Ring-opening terpolymerization of L-lactide (LA), -caprolactone (CL), and glycolide (GA) was performed in the presence of tin (II) 2-ethylhexanoate at 170 degrees C. Random terpolyesters with weight-average molecular weight up to 130,000 g/mol were obtained. These terpolyesters, especially those with LA:CL:GA composition of 3:1:1, provided good coating integrity following spraying onto bare metal stents. The semi-synthetic macrolide immunosuppressant, everolimus, was incorporated into the terpolyester coating, and its release from the stent was evaluated. Unlike PLLA homopolymers, which are immiscible with the drug and non-optimal for controlled release, these terpolymers gave excellent control in a screening study, by tuning terpolymer molecular weight, relative monomer ratio, and drug-to-polymer ratio. Adjusting the polymer properties to improve drug solubility (or miscibility) in the polymer coating was found beneficial to the release profile.

In this paper we reported the preparation and characterization of the nanostrutured CdS/ZnO nanoarray thin film, based on the free-standing ZnO nanorod-array. The method was simple and low-cost. The ZnO nanorod-arrays were synthesized on F-doped tin oxide glass (TCO) substrate by hydrothermal method, then coated with CdS nanoparticles closely via chemical bath deposition method. The resulting thin films showed better photoelectrochemical performances than those of CdS/ZnO nanoparticles thin films. Under the illumination of AM 1.5 simulated sunlight (30 mW/cm2), the photocurrent of the samples achieved to 0.72 mA/cm2.

Uniform crystalline CdSnO3.3H2O nanocubes with a 28-35 nm edge length have been obtained via the ion-exchange reaction of Na2Sn(OH)6 in a CdSO4 aqueous solution, assisted by ultrasonic treatment. Precursor Na2Sn(OH)6 crystals were prepared via hydrothermal treatment in an ethanol/water solution. The formation of CdSnO3.3H2O nanocubes resulted from the strain during the ion-exchange process. The influences of reaction conditions, such as ion-exchange (ultrasonic treatment) duration, solvent constitutes, surfactant, and pH on the formation of CdSnO3.3H2O crystals were described. Crystalline CdSnO3 and Cd2SnO4 have been obtained by thermal treatment at 300 and 500 degrees C, respectively, for 5 h under an inert-gas protecting condition using CdSnO3.3H2O nanocubes as the precursor. The cube shape of CdSnO3.3H2O was sustained after thermal decomposition to CdSnO3.

Polarization-sensitive color originates from polarization-dependent reflection or transmission, exhibiting abundant light information, including intensity, spectral distribution, and polarization. A wide range of butterflies are physiologically sensitive to polarized light, but the origins of polarized signal have not been fully understood. Here we systematically investigate the colorful scales of six species of butterfly to reveal the physical origins of polarization-sensitive color. Microscopic optical images under crossed polarizers exhibit their polarization-sensitive characteristic, and micro-structural characterizations clarify their structural commonality. In the case of the structural scales that have deep ridges, the polarization-sensitive color related with scale azimuth is remarkable. Periodic ridges lead to the anisotropic effective refractive indices in the parallel and perpendicular grating orientations, which achieves form-birefringence, resulting in the phase difference of two different component polarized lights. Simulated results show that ridge structures with reflecting elements reflect and rotate the incident p-polarized light into s-polarized light. The dimensional parameters and shapes of grating greatly affect the polarization conversion process, and the triangular deep grating extends the outstanding polarization conversion effect from the sub-wavelength period to the period comparable to visible light wavelength. The parameters of ridge structures in butterfly scales have been optimized to fulfill the polarization-dependent reflection for secret communication. The structural and physical origin of polarization conversion provides a more comprehensive perspective on the creation of polarization-sensitive color in butterfly wing scales. These findings show great potential in anti-counterfeiting technology and advanced optical material design.