Photo-catalytic heat mirror with a thick titanium dioxide layer

Some of the heat mirrors, which have high transmittance in the visible region and high reflectance in the infrared, consist of three thin titanium compound stacked films, TiO₂/TiN/TiO₂ on glass substrate. TiO₂ is known to have excellent photo-catalytic properties and the top layer may be expected to work as a photo-catalyst as well as the anti-reflection coating. However, strong thickness dependence of the photo-catalytic properties has been reported and the optimum thickness of the top layer for the heat mirror was too thin for the photo-catalytic properties for decomposition of acetaldehyde gas. In this report, we show a possibility to realize a multi-functional heat mirror which shows the photo-catalytic and heat mirror effects simultaneously by optical calculation and preliminary experiments. We found top TiO₂ thickness of 350–400 nm or about 1170 nm showed high heat mirror performance. This thickness was enough to show the photo-catalytic properties.     

Air permeability of the artificially synthesized Zn-Al-Mg alloy rusts

The rust particles of Zn-Al-Mg alloys were synthesized from aqueous solutions dissolving ZnCl₂, AlCl₃, and MgCl₂ at different atomic ratios of the metal ions. The crystal phase and particle morphology of the products depended on the composition of the starting solutions. The compactness of the layers of the products was estimated by measuring their air permeability. The layer of mixed metal hydroxide chloride formed at Zn:Al:Mg = 1:1:1 showed a highest compactness, that was ascribed to the preferred orientation of the fine plate particles. The addition of Mg(II) made plate particles smaller to give more compact layers.     

Preparation of CdSSe-ZnS superlattice,SrS, and CdSSe-SrS superlattice by hot-wall epitaxy,and applications to electroluminescent devices

CdSSe (manganese-doped, E_g = 1.9–2.5 eV, lattice constant a = 6.05–5.8A)-ZnS (Eg = 3.56 eV, a = 5.41A) superlattices, SrS (cerium-doped, E = 4.4 eV, a = 6.02A) layers, and CdSSe-SrS (cerium-doped) superlattice layers nave been prepared by hot-wall epitaxy, and the properties and the electroluminescent device characteristics of the active layers are reported. For the superlattices with ZnS, the maximum luminance was 800 cd/m² at an applied sinusoidal voltage (V_o-p = 200 V) with frequency 1kHz, and the wavelength of the spectral peak was 610 nm due to the large strain caused by the lattice mismatch (8–15%) between the CdSSe and ZnS layers. The maximum luminance and Comisson Internationale de Enluminure (CIE) chromaticity of CdS(Mn)-ZnS superlattices and CdSe(Mn)-ZnS superlattice devices were 557cd/m² and (x,y) = (0.58,0.41) and 982 cd/m² and (0.61, 0.38), respectively. For superlattices with SrS, the maximum luminance of the device with the SrS (cerium-doped) active layer was nearly 700 cd/m² at a voltage of 340V. Blue electroluminescent emission was observed in the photon wavelength region less than 450 nm, due to carriers dropping into the quantum wells of the device with the CdSSe-SrS superlattice active layer.     

A long-term follow-up study of serial magnetic resonance images in patients with delayed encephalopathy after acute carbon monoxide poisoning

We report a case of vasculitis in a 67-year-old woman who successively developed over a four-month period clinical manifestations suggestive of rheumatoid arthritis, lupus, sicca, syndrome and finally giant cell arteritis. All her symptoms resolved promptly upon discontinuation of enalapril and none recurred over the five-year follow-up period. The only residual manifestation is Jaccoud's arthropathy of the hands.     

Needle penetrometry with variable force loading for measuring viscosity of pelletized coal upon heating

A needle penetrometry was performed loading steady force in a range from 1×10⁻³ to 2 N to pelletized coal upon heating via a cylindrical needle. From the observed effects of shear rate on apparent viscosity of softening coal pellet, defined as the shear-rate to shear-stress ratio, it was found that the pellet behaved as a Newtonian fluid for shear rates lower than a critical one while as a pseudo-plastic fluid for higher shear rates. The penetrometry was also carried out varying the force with time. The variable force loading enabled to maintain the shear rate well below the critical one, and thereby to measure the apparent viscosity of coal pellets as Newtonian fluids over a temperature range from 600 to 800 K. Upon heating at 10 K min⁻¹, the apparent viscosity of Goonyella coal pellet decreased from about 10¹⁰ Pa s at 640 K down to a minimum of about 10⁴ Pa s at 755 K, and increased up to 10⁹ Pa s at 800 K. In a course of heating as above, the viscosity of Blind Canyon coal pellet decreased above 600 K, underwent a minimum of about 10⁶ Pa s at 715 K, and increased up to 10¹⁰ Pa s at 770 K. Decreasing the heating rate from 10 to 3 K min⁻¹ caused the minimum viscosities of the pellets to increase by 1-2 orders of magnitude.     

Theoretical Prediction of the Structure and Properties of Cubic Spinel Nitrides

The structure and properties of cubic spinel nitrides were investigated based on first-principles theoretical calculations. The lattice constants, bulk moduli, band structures, electronic bonding, and lattice stability of thirty-nine single and double nitrides were studied. The single spinel nitrides of the form c -A₃N₄ (where A is a Group IVA element), except c -Hf₃N₄, are all semiconductors with band gaps ranging from an indirect gap of 0.07 eV in c -Ti₃N₄ to a direct gap of 3.45 eV in c -Si₃N₄. For double nitrides of the form c -AB₂N₄ (where A and B are Group IVA (Ti, Zr, Hf) or IVB (C, Si, Ge, Sn) elements), both metallic and insulating band structures are possible. The stability of the double spinel nitrides, relative to single nitrides, is dependent on the optimal cation radii and polyhedral volumes at the tetrahedral A sites and the octahedral B sites. Of the thirty-two double nitrides, only nine are predicted to be energetically favorable. Among the potentially stable phases, the most interesting ones are c -CSi₂N₄ (which has an exceptionally strong covalent bonding and large bulk modulus), c -SiGe₂N₄ (which has an energetically favorable direct band gap of 1.85 eV), and c -SiTi₂N₄ (which is metallic).     

Analysis of γ′/γ equilibrium in Ni−Al−X alloys by the

Various characteristics of γ′/γ phase equilibrium in ternary Ni−Al-X alloys are analyzed by the cluster variation method (CVM) with the phenomenological Lennard-Jones pair potential. Among the eleven alloy elements studied, three types of substitution behavior in γ′,i.e., the preferential substitution for Ni sites (Co and Cu), the almost entire substitution for Al sites (Ti, Nb, Mo, Hf, Ta, and W), and the substitution for both (Cr, Mn, and Fe), are recognized depending upon the relative magnitude of the Ni−X and Al−X interactions. In the last type, the substitution site appears to depend remarkably upon the Al and/or X concentrations in γ′: while X atoms enter preferentially, the Al sublattice in the case that the sum of the two concentations is less than the stoichiometry composition (0.25), they begin to enter the Ni sublattice as the sum exceeds it. The predicted substitution behavior is in good agreement with direct and indirect experimental evidences thus far reported. The direction of γ′/γ equilibrium phase boundaries, the equilibrium partition coefficient of X, and the effects of alloying upon the order-disorder transformation temperature from metastable γ′ to γ all appear to be closely related to substitution behavior. Also, the variation of lattice constants of γ′ and γ with the alloy element concentration may be better understood by collation with the substitution sites or the short range order in each phase.