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31.
32.
In search of an efficient transdermal drug delivery system (TDDS), a polyhydroxyalkanoate (PHA)-based system with a polyamidoamine dendrimer was examined. Tamsulosin was used as the model drug. The dendrimer was found to act as the weak enhancer. By adding the dendrimer, the dendrimer-containing PHA matrix achieved the clinically required amount of tamsulosin permeating through the skin model. This is also the first report of the application of PHA and dendrimer to the TDDS.  相似文献   
33.
The mechanical reliability of products must be assured for scaling up and production of complex-shaped components by spark plasma sintering (SPS) of spray-dried granules. The evolution of morphologies of pores and defects, which control the mechanical strength, is investigated by using synchrotron X-ray multiscale tomography during SPS of alumina granules at 1300 °C. While large defects arising from the hierarchical granule packing structure cannot be removed by pressureless sintering, crack-like defects and branched rodlike defects are almost eliminated by SPS at stresses higher than 30 and 50 MPa, respectively. But, small ellipsoidal porous regions, which may arise from aggregates or dimples of granules, cannot be removed even at a pressure of 50 MPa. A very large defect is also found by using micro-CT. It is supposed that this defect is formed from a large void in loosely packed granules. The shrinkage of large voids and the elimination of crack-like defects are explained by the theoretical prediction based on the continuum theory of sintering.  相似文献   
34.
The modifying of the JT-60U magnet system to the superconducting coils is progressing as a satellite facility for ITER by both parties of Japanese government and European commission in the Broader Approach agreement. The magnet system requires current supplies of 25.7 kA for 18 TF coils and of 20 kA for 4 CS modules and 6 EF coils. The magnet system generates an average heat load of 3.2 kW at 4 K to the cryogenic system. The feeder components connected to the power supply provide current supply. The cooling pipes connected to the cryogenic system provide coolant supply. The instrumentation of the JT-60SA magnet system is used for its operation.  相似文献   
35.
The development of tissue clearing technologies allows 3D imaging of whole tissues and organs, especially in studies of the central nervous system innervated throughout the body. Although the three-dimensional imaging of solvent-cleared organs (3DISCO) method provides a powerful clearing capacity and high transparency, the rapid quenching of endogenous fluorescence and peroxide removal process decreases its practicability. This study provides a modified method named tDISCO to solve these limitations. The tDISCO protocol can preserve AAV-transduced endogenous EGFP fluorescence for months and achieve high transparency in a fast and simple clearing process. In addition to the brain, tDISCO was applied to other organs and even hard bone tissue. tDISCO also enabled us to visualize the long projection neurons and axons with high resolution. This method provides a fast and simple clearing protocol for 3D visualization of the AAV- transduced long projection neurons throughout the brain and spinal cord.  相似文献   
36.
Masaya Shigeta 《Thin solid films》2007,515(9):4217-4227
Numerical analysis is conducted for the titanium-based boride and silicide nanoparticle synthesis using an induction thermal plasma including the material evaporation process and the nanoparticle growth process with nucleation and co-condensation. Both systems present the nano-scaled particle size distributions. Ti-B system shows the smaller particle diameter, sharper distribution, larger particle number density, and wider range of the composition than Ti-Si system. Ti-Si system provides a narrower range of the silicon content due to the simultaneous co-condensation of titanium and silicon. Finally the correlation between the particle size and the nonmetal content of the synthesized nanoparticles is presented on a chart.  相似文献   
37.
This paper describes the improvements in launching stability and launching velocity of the linear accelerator (LAC). The authors have designed and produced a railgun using the LAC for weaving loom shuttles. The LAC is an electromagnetic launcher which enables a projectile to be launched at a speed of more than 50 m/s. Basically, it consists of a unipole linear dc motor and operates the same principle as dc rotary motors, the most difficult problem in this system being the stabilization of the current collection on the projectile. Then, various launch experiments have been conducted. As a result, the carbon projectile was launched at a speed of 73 m/s using double-state-type LAC.  相似文献   
38.
A simultaneous measurement of the liquid velocity and interface profiles was performed for stratified-smooth and wavy flows in a horizontal duct using a ultrasonic velocity profile (UVP) meter. The influences of the reflections of ultrasonic pulses at the gas–liquid interface and channel bottom were reduced by using an absorbent for the ultrasonic pulses on the duct bottom wall and optimization of the liquid level and time interval between pulses. For a smooth–stratified flow, good comparison was obtained with a velocity profile obtained by particle tracking velocimetry (PTV) for video pictures taken simultaneously at the UVP measurement. Polystyrene beads were used as the reflector and tracers respectively, for the UVP and PTV measurements. The velocity profiles measured for a wavy flow with periodically-generated interfacial waves agreed well with the theoretical prediction for solitary waves. Turbulence component appeared in the velocity profiles of both the smooth–stratified and wavy flows.  相似文献   
39.
Various Ti-oxide based photocatalysts such as the highly dispersed Ti-oxide species within zeolite frameworks, TiO2 nano-particles hybridized with hydrophobic zeolite adsorbents as well as visible light responsive TiO2 thin films have been successfully prepared. Characterization studies at the molecular level, such as X-ray absorption fine structure (XAFS) and photoluminescence (PL), revealed that the highly dispersed Ti-oxide species within the nano-spaces of zeolites possess a tetrahedral coordination and that they demonstrate unique and high performance for the photocatalytic decomposition of NOx and the photocatalytic reduction of CO2 with H2O. A high photocatalytic reactivity for the TiO2 semiconducting photocatalysts could be achieved by blending them with hydrophobic siliceous zeolites which was equal to the performance of TiO2 deposited with expensive Pt particles. The role of the siliceous zeolites can be described as a so-called “catch and release effect of organic compounds”, i.e., (i) the condensation of the reactants within the hydrophobic cavities of zeolites and; (ii) the efficient diffusion of the reactant onto the TiO2 photocatalytic sites. Furthermore, a novel photocatalytic system which can convert abundant solar energy into renewable H2 energy by the decomposition of H2O into H2 and O2 can also be achieved by using visible light responsive TiO2 thin film photocatalysts prepared by a RF-magnetron sputtering deposition method. The conversion efficiency of solar energy into H2 energy may be estimated at ca. 0.1% from the initial rate of H2 evolution.  相似文献   
40.
Morphologic control of Pt supported titanate nanotubes was attempted by the hydrothermal hot-pressing (HHP) technique in order to improve the handleability as a photocatalyst. The bulk of Pt-nanocrystal supported titanate nanotubes was successfully fabricated without the H2 reduction process by applying the HHP technique. The bulky Pt-nanocrystal supported titanate nanotubes possessed dense microstructures, significantly sharp distributions of mesopores, and high Brunauer–Emmett–Teller (BET) surface area. Furthermore, the bulky Pt-nanocrystal supported titanate nanotubes showed the photocatalytic degradation activities of 2-propanol aqueous solution under UV-light irradiation.  相似文献   
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