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111.
Matoba O  Sawasaki T  Nitta K 《Applied optics》2008,47(24):4400-4404
An optical system for authentication using a 3D (3D) random phase object with various wavelength readouts is proposed. The 3D phase object without surface modulation is secure when the scattering is strong enough because it prevents from the interferometric measurement. The identification is implemented by the correlation between a measured speckle pattern of the 3D phase object and stored speckle patterns. For accurate identification, two speckle patterns of the 3D object obtained by illuminating two wavelengths are used. Experimental demonstrations and numerical evaluations of wavelength selectivity are presented.  相似文献   
112.
For electrode materials of Pb(Zr,Ti)O3 (PZT) thin films in ferroelectric random access memory (FeRAM), various materials have been studied. As new electrode material with which the polarization and fatigue properties are improved, we take notice of barium metaplumbate BaPbO3 (BPO). Because the BPO contained lead (Pb) and oxygen is conductor that adopted same perovskite structure as PZT. BPO thin films were prepared by rf magnetron sputtering on various substrates. (SiO2/Si, MgO, Al2O3 and Pt-coated substrates), and influence of growth conditions (sputtering gas, rf power, the substrate-heating temperature and post anneals) on crystallization and conductivity were investigated. In case of post anneal after sputtering at room temperature, perovskite single phase was obtained above 400°C. In case of substrate heating while sputtering, without post anneal, perovskite single phase was obtained at 350–500°C on SiO2/Si substrates (110) preferred orientation BPO films obtained at low temperature, and resistivity of the films decreased at decreasing sputtering temperature. Resistivity of the film at substrate temperature 350°C was 3 × 10?3 Ω cm. In the case of single crystal substrate, the BPO films were epitaxially grown. Orientation of the films was varied with the sputtering condition. The epitaxial PZT thin films were also grown on the BPO, revealing that PZT(111)[011] //BPO(111)[011] //Pt(100)[011] //MgO(100)[011] and PZT(111)[011] //BPO(111)[011] //Pt(111)[011] //Al2O3(001)[100] structures were obtained, and their ferroelectric properties were also evaluated.  相似文献   
113.
Dihydroxy fatty acid-based (DF) dendron-stabilized gold nanoparticles (AuNps) were synthesized without adding any external reducing or stabilizing agent. Each DHA base dendron (G1, G2, or G3) possesses a single thiol at the focal point and free -OH groups at the other terminal and as a result can be used to reduce AuCl4 to Au0 and stabilize the nascent AuNps by the thiol group. The size and distribution of the AuNp produced can also be correlated with the rate of Au (III) reduction. TEM images vividly demonstrate the specific morphology of gold nanoparticles with different sizes and shapes obtained by using different generations of DF dendrons.  相似文献   
114.
The experimental results for moisture measurement of green tea usingmicrowave free-space technique are presented. The method is based on a ratioof phase shifts at two microwave frequencies after propagating through asample of green tea. It is shown that the method provides the moisturecontent of tea leaves from 6% to 32% on a dry basis without any knowledge onthe thickness and the density of sample. The mean and the maximum errors inthe moisture determination for tea leaves were 1.2% and 3.7%, respectively.  相似文献   
115.
Oxidation kinetics of low-oxygen silicon carbide fiber   总被引:2,自引:0,他引:2  
The effect of partial pressure and temperature on the oxidation rate of low-oxygen silicon carbide fiber (Hi-Nicalon) has been investigated. The initial oxidation rate was described by a two-dimensional disc contracting formula for reaction control, and the activation energy was 155 kJ/mol. The rate at the later stage of oxidation obeyed the equation for diffusion control, and the activation energy was 109 kJ/mol. Both the rate constants were proportional to oxygen partial pressure. The diffusion species through the SiO2 film are considered to be oxygen molecules.  相似文献   
116.
This paper reviews North Atlantic shelf seas palaeoclimate during the interval 4-3Ma, prior to and incorporating the 'Mid-Pliocene warm period' (ca 3.29-2.97Ma). Fossil assemblages and stable isotope data demonstrate northwards extension of subtropical faunas along the coast of the Carolinas-Virginia (Yorktown and Duplin Formations) relative to the present day, suggesting a more vigorous Florida Current, with reduced seasonality and warm water extending north of Cape Hatteras (reconstructed annual range for Virginia 12-30 degrees C). This interpretation supports conceptual models of increased meridional heat transport for the Pliocene. Sea temperatures for Florida (Lower Pinecrest Beds) were similar to or slightly cooler than (summers 25-27 degrees C) today, and were probably influenced by seasonal upwelling of cold deep water. Reduced seasonality is also apparent in the Coralline Crag Formation of the southern North Sea, with ostracods suggesting winter sea temperatures of 10 degrees C (modern 4 degrees C). However, estimates from Pliocene bivalves (3.6-16.6 degrees C) are similar to or cooler than the present day. This 'mixed' signal is problematic given warmer seas in the Carolinas-Virginia, and climate model and oceanographic data that show warmer seas in the 'Mid-Pliocene' eastern North Atlantic. This may be because the Coralline Crag Formation was deposited prior to peak Mid-Pliocene warmth.  相似文献   
117.
Polycarbosilane-derived low-oxygen SiC fibers, Hi-Nicalon, were heat-treated for 36 ks at temperatures from 1273 to 1773 K in CO2 gas. The oxidation of the fibers was investigated through the examination of mass change, crystal phase, resistivity, morphology, and tensile strength. The mass gain, growth of β-SiC crystallites, reduction of resistivity of the fiber core, and formation of protective SiO2 film were observed for the fibers after heat treatment in CO2 gas. SiO2 film crystallized into cristobalite above 1573 K. Despite the low oxygen potential of CO2 gas ( p O2= 1.22 Pa at 1273 K − 1.78 × 102 Pa at 1773 K), Hi-Nicalon fibers were passively oxidized at a high rate. There was a large loss of tensile strength in the as-oxidized state at higher temperatures because of imperfections in the SiO2 film. On the other hand, the fiber cores showed better strength retention even after oxidation at 1773 K.  相似文献   
118.
Rab11b, abundantly enriched in endocytic recycling compartments, is required for the establishment of the machinery of vesicle trafficking. Yet, no report has so far characterized the biological function of Rab11b in osteoclastogenesis. Using in vitro model of osteoclasts differentiated from murine macrophages like RAW-D cells or bone marrow-derived macrophages, we elucidated that Rab11b served as an inhibitory regulator of osteoclast differentiation sequentially via (i) abolishing surface abundance of RANK and c-Fms receptors; and (ii) attenuating nuclear factor of activated T-cells c1 (NFATc-1) upstream signaling cascades, following RANKL stimulation. Rab11b was localized in early and late endosomes, Golgi complex, and endoplasmic reticulum; moreover, its overexpression enlarged early and late endosomes. Upon inhibition of lysosomal function by a specific blocker, chloroquine (CLQ), we comprehensively clarified a novel function of lysosomes on mediating proteolytic degradation of c-Fms and RANK surface receptors, drastically ameliorated by Rab11b overexpression in RAW-D cell-derived osteoclasts. These findings highlight the key role of Rab11b as an inhibitor of osteoclastogenesis by directing the transport of c-Fms and RANK surface receptors to lysosomes for degradation via the axis of early endosomes-late endosomes-lysosomes, thereby contributing towards the systemic equilibrium of the bone resorption phase.  相似文献   
119.
A new contrast enhanced lithography (CEL) process using Chinese rosin as a binder is described. This binder is soluble in both non-polar organic solvent and aqueous alkaline solution. Good coatability with organic solvent, no formation of mixing layer, and direct development without removing the CEL layer are the major advantages of this process. Among the three different kinds of photobleachable dyes, DZ-2 (diazonium salt) has the best optical property and the resist profile is improved on g-line reduction projection printing at the smallest dose. Moreover, this DZ-2—Chinese rosin system is also effective at 365 nm, and the resist profile and the focus margin are improved on i-line reduction projection printing by using this system.  相似文献   
120.
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