Titanium dioxide (TiO_2) is the most intensely investigated photocatalyst and until today the only one that has already been commercialized and that is involved in many applications such as self-cleaning materials, dye-sensitized solar cells, as well as water and air purification. Consequently, an exponential growth of research activities concerning the nanoscience and nanotechnology of TiO_2 has been observed during the last decades. These raising research activities have recently lead to the synthesis of nanosized TiO_2 nanoparticles and nanostructures with different shapes, morphologies and phase compositions. Thus, the present chapter focuses mainly on the synthesis of these nanomaterials. The thermodynamic stability, the transition between different TiO_2 polymorphs and the surface properties of these polymorphs are presented with the aim to utilize this information for a better understanding of the mechanism of the formation of TiO_2 nanomaterials. The photocatalytic applications of these TiO_2 nanomaterials are also discussed.

关键词：电池材料；光催化剂；纳米材料

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When an energetic ion passes through a material, an ion track may be produced along the ion path if the electronic stopping power S_e is larger than a material dependent threshold value. Although there are a number of studies on the ion tracks produced in crystalline materials using transmission electron microscopy (TEM), there are only a limited number of TEM studies on the ion tracks in amorphous materials due to a lack of sufficient contrast. In this report, the ion tracks in amorphous Si_3N_4 films irradiated with 120-720 keV C_(60)~(+,2+) ions were observed with TEM and high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM). The radial density distribution of the ion track was derived from the observed HAADF-STEM images.

关键词：电池材料；化学反应；离子轨道

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Nanostructured materials have attracted great attention in recent time because of their innovative characteristics and potential applications in the fields of catalysis, drug delivery, sensors and pollution abatement measures. Stabilized metal nanoparticles (size ＜ 10 nm) with very active surface atoms, high selectivity and recyclability have lead to a new generation of 'Nanocatalysts' for sustainable green chemistry for industrial applications like fine and bulk chemicals, Pharmaceuticals, fuel cell, petroleum refineries, environmental catalysis and many other fields. The present chapter summarizes the techniques for preparations, characterizations, and catalytic activities of different metals nanoparticles for organic transformations.

关键词：新型电池；燃料电池；纳米材料

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Gamma-ray luminosities of some quasar-associated blazars imply jet powers reaching values comparable to the accretion power even if assuming very strong Doppler boosting and very high efficiency of gamma-ray production. With much lower radiative efficiencies of protons than of electrons, and the recent reports of very strong coupling of electrons with shock-heated protons indicated by Particlein- Cell (PIC) simulations, the leptonic models seem to be strongly favored over the hadronic ones. However, the electron-proton coupling combined with the ERC (External-Radiation-Compton) models of gamma-ray production in leptonic models predict extremely hard X-ray spectra, with energy indices (alpha(sup x)) approximately 0. This is inconsistent with the observed 2-10 keV slopes of blazars, which cluster around (alpha(sup x)) approximately 0.6. This problem can be resolved by assuming that electrons can be efficiently cooled down radiatively to non-relativistic energies, or that blazar spectra are entirely dominated by the SSC (Synchrotron-Self Compton) component up to at least 10 keV.

关键词：类星体；X射线谱；加速；伽玛源

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Fission fragment direct energy conversion has been considered in the past for the purpose of increasing nuclear power plant efficiency and for advanced space propulsion. Since the fragments carry electric charge (typically in the order of 20 e) and have 100 MeV-range kinetic energy, techniques utilizing very high-voltage DC electrodes have been considered. This study is focused on a different approach: the kinetic energy of the charged fission fragments is converted into alternating current by means of a traveling wave coupling scheme (Traveling Wave Direct Energy Converter, TWDEC), thereby not requiring the utilization of high voltage technology.

关键词：能量转换；片段；行波;；粒子能量；原子核裂变

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Spectral reflectance data through the visible regime was collected at Las Campanas Observatory in Chile using an imaging spectrograph on one of the twin 6.5-m Magellan telescopes. The data were obtained on 1-2 May 2012 on the 'Landon Clay' telescope with the LDSS3 (Low Dispersion Survey Spectrograph 3). Five pieces of Geosynchronous Orbit (GEO) or near-GEO debris were identified and observed with an exposure time of 30 seconds on average. In addition, laboratory spectral reflectance data was collected using an Analytical Spectral Device (ASD) field spectrometer at California Polytechnic State University (Cal Poly) in San Luis Obispo on several typical common spacecraft materials including solar cells, circuit boards, various Kapton materials used for multi-layer insulation, and various paints. The remotely collected data and the laboratory-acquired data were then incorporated in a newly developed model that uses a constrained least squares method to unmix the spectrum in specific material components. The results of this model are compared to the previous method of a human-in-the-loop (considered here the traditional method) that identifies possible material components by varying the materials and percentages until a spectral match is obtained. The traditional model was found to match the remotely collected spectral data after it had been divided by the continuum to remove the space weathering effects, or a reddening of the materials. The constrained least-squares model also used the de-reddened spectra as inputs and the results were consistent with those obtained through the traditional method. For comparison, a first-order examination of including reddening effects into the constrained least-squares model will be explored and comparisons to the remotely collected data will be examined. The identification of each object s suspected material component will be discussed herein.

关键词：空间碎片；光谱反射率；同步轨道；最小二乘法

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Superparamagnetic iron oxide nanoparticle (SPION) has attracted a great deal of attention in the fields of medicine and biology due to its non-toxicity, large specific surface area, amenability to various surface fuctionalization, and unique magnetic properties. For biomedical applications, we synthesized two kinds of SPIONs by co-precipitation and polyol methods, designated as C- and P-SPIONs, respectively. To increase their solubility and stability in an aqueous solution, both of the SPIONs were functionalized with hyperbranched polyglycerol (PG) through ring-opening polymerization of glycidol. Scanning transmission electron microscopy (STEM) and dynamic light scattering (DLS) measurements revealed that the P-SPION provided individual nanoparticles without aggregation after the PG fuctionalization. This P-SPION-PG was highly soluble not only in pure water (＞ 40 mg/mL), but also in a phosphate buffer solution (＞ 25 mg/mL). Such high solubility enabled separation of P-SPION-PG according to their size by size exclusion chromatography (SEC). The size-separated P-SPION-PG shows a gradual increase in transverse relaxivity (r_2) with increasing particle size. The hydroxyl group in PG also serves as a scaffold for further surface functionalization. For targeted cell labeling, we functionalized P-SPION-PG through multi-step organic transformations (-OH → -OTs (tosylate) → -N_3 → -RGD) including click chemistry as a key step to impart targeting specificity by immobilization of cyclic RGD peptide on the surface. The targeting effect was demonstrated by the cell experiments; P-SPION-PG-RGD was taken up by the cells overexpressing α_vP_3-integrin such as U87MG and A549. In addition, near-infrared (NIR) fluorescence dye (IRdye 800CW) was immobilized on the surface of P-SPION-PG through amide linkage. The resulting P-SPION-PG-IRdye showed good solubility in phosphate buffered saline (PBS) and strong fluorescence in NIR region, which may find application in optical/MR bimodal imaging.

关键词：电池磁极；氧化铁材料；电能转换

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A micromechanics analysis modeling method was developed to analyze the damage progression and fatigue failure of fabric reinforced composite structures, especially for the brittle ceramic matrix material composites. A repeating unit cell concept of fabric reinforced composites was used to represent the global composite structure. The thermal and mechanical properties of the repeating unit cell were considered as the same as those of the global composite structure. The three-phase micromechanics, the shear-lag, and the continuum fracture mechanics models were integrated with a statistical model in the repeating unit cell to predict the progressive damages and fatigue life of the composite structures. The global structure failure was defined as the loss of loading capability of the repeating unit cell, which depends on the stiffness reduction due to material slice failures and nonlinear material properties in the repeating unit cell. The present methodology is demonstrated with the analysis results evaluated through the experimental test performed with carbon fiber reinforced silicon carbide matrix plain weave composite specimens.

关键词：细观力学；疲劳（材料）；损害评估；热力学性质；复合材料结构

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NREL and Solar Power Industries will cooperate to evaluate technology for producing solar grade silicon from industrial waste of the phosphorus industry, as developed by the Institute of Physics and Technology (IPT), Kazakhstan. Evaluation will have a technical component to assess the material quality and a business component to assess the economics of the IPT process. The total amount of silicon produced by IPT is expected to be quite limited (50 kg), so evaluations will need to be done on relatively small quantities (5 kg/sample). Department of Energy (DOE) laboratories, including NREL, have been placing subcontracts for research and development services with scientific institutes in the Newly Independent States (NIS) under various DOE programs for many years.

关键词：硅太阳能电池；实验室；太阳能

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Titanium dioxide has been used as the white pigment since the ancient times.95% of its current usage in industry involves paints, cosmetics, plastics, paper, and food. However, in near future the economic impact of titanium dioxide seems to be controlled by energy related applications mostly. Therefore, this chapter projects a brief outlook on the added value provided by the titanium dioxide structures in new and emerging technologies of the energy sector. The applications focused are: solar fuels, solar cells, fuel cells, Li ion batteries and solid state lighting. In those applications, TiO_2 standouts with its chemical and thermal stability, morphology variety, position of conduction and valance band energy levels, optical properties and cost.

关键词：燃料电池；太阳能电池；新型电池

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