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91.
New Pb-based 1222 cuprates containing phosphorus have been synthesized in the (Pb0.75P0.25)Sr2- (RE2–xy Ce x Sr y )Cu2O z (RE = Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, and Y) systems. The almost-single phase samples are obtained for 0.5≤x≤1.0 and y=0.1 in the cases of RE = Nd, Dy, Ho, Er, Tm, Yb and Y, while for 0.3≤x≤1.0 and y=0.1 in the cases of RE = Sm, Eu and Gd. The samples crystallize in a tetragonal lattice, the lattice parameters a and c are decreasing with the decrease of the ionic radius of the RE element. Even after annealing under 143 atm O2 atmosphere at 400 °C, almost all the samples with the common values x=0.5 and y=0.1 are semiconductors with a transport process followed by three-dimensional variable range hopping. However, the samples of RE = Sm, Eu and Gd, which are of almost single 1222 phase, even for x=0.3 and y=0.1, show superconductivity with the onsets at about 25 K, 20 K and 22 K, respectively. Through this study, we find very important procedure for discovery of new superconducting 1222 compound.  相似文献   
92.
93.
In this paper we describe an algorithm to render the asterism or chatoyancy effect in gems. This effect is due to light dispersion caused by inclusions consisting of vast numbers of thin fibrous needles. We develop models for distribution of the microfacet directions of the inclusions and of the light dispersion by them. Based on these models we derive an algorithm to render gems with the asterism effect. By introducting a ray distribution map, a new algorithm for tracing dispersed light rays is developed.  相似文献   
94.
Tables to indicate the present status of powder technology educational programs in Japan are presented on the basis of a questionnaire style investigation by the Society of Powder Technology, Japan. Research activities in universities and research institutes are also included in the tables.

The activities of both the Society of Powder Technology and the Association of Powder Process Industry and Engineering in Japan are also introduced by explaining their organizations and annual events.  相似文献   
95.
Minimum fluidization data at elevated temperatures and pressures are relatively scarce in the literature. This study was undertaken to provide some new data under these conditions. Minimum fluidization velocities at temperatures up to 800°K and pressures up to 5 MPa were measured for uniformly-sized glass beads with diameters between 0.2 mm and 4 mm in beds ranging in diameter from 30 mm to 50 mm. The experimental results are compared with a number of empirical correlations from the literature to determine the validity of the correlations under these elevated temperature and pressure conditions.  相似文献   
96.
We have developed pulse‐width modulation (PWM) with current uniformization for active‐matrix organic light‐emitting diode (AM‐OLED) micro‐displays on Si large‐scale integration (LSI) chips. This driving method can simultaneously solve luminance unevenness and image sticking due to characteristic deviations and degradations of driving transistors and OLEDs. With the use of circuit simulation, it is verified that the PWM with current uniformization (PWM‐CU) can simultaneously achieve precise gray scale and exceedingly improve luminance uniformity. Moreover, an actual panel is designed and fabricated, where the OLEDs are layered on the Si LSI chip. It is found that the luminance uniformity can be improved within 2% to 3%. It is meaningful that the correct images can be displayed using the PWM‐CU for the first time for AM‐OLED micro‐displays on Si LSI chips.  相似文献   
97.
An indium oxide‐based precursor solution has been developed by spin coating method. In order to apply this material to mass production, material, process, and equipment optimizations for slot die coating have been implemented. Slot die coating is a cost‐effective and scalable process and already applied to photoresist materials in the display industry. The indium oxide‐based precursor solution has been coated on bare glasses and thin‐film transistor substrates by a mass production‐type slot die coater. Mobility of over 10 cm2/Vs is achieved for the first time for a large area at an annealing temperature of 350 °C. The homogeneity of the film will be presented.  相似文献   
98.
The refractive index dispersion and infrared (IR) reflection spectra of soda magnesium silicate glasses with low Rayleigh scattering were measured to evaluate their potential for use in fabricating ultralow-loss fibers. The zero-material dispersion wavelength (λ0) was found to be around 1.5 μm, which is one of the key wavelengths in the present telecommunication system. The compositional dependence of λ0 was found to relate to the population of nonbridging oxygen. Since the oscillation strength and frequency of the Si—O stretching vibrations of the glasses were found to be smaller than those of silica glass, their IR absorption loss was considered to be less than that of silica glass. The minimum loss due to the intrinsic factors, Rayleigh scattering and IR absorption, was estimated to be 0.06 dB/km at 1.6μm.  相似文献   
99.
A feeding deterrent against larvae of a papilionid butterfly,Luehdorfia puziloi (Parnassiinae), a specialist onAsiasarum plants (Aristolochiaceae), was isolated from another aristolochiaceous plant,Heterotropa aspera. Antifeedant activity was exhibited by then-hexane-soluble fraction that proved to contain at least two active components. One of the deterrents was identified as a neolignan compound, asatone. The concentration of asatone inH. aspera was estimated at approximately 225 ppm, and larval feeding ofL. puziloi was significantly deterred at concentrations over 90 ppm. By contrast, asatone was not detectable (< 1 ppm, if any) in its host plant,Asiasarum sieboldii.  相似文献   
100.
The solubility of butane and isobutane in molten polypropylene (PP) and polystyrene (PS) was measured at pressures up to 3 MPa and along four isotherms from 438 to 483 K for PP and from 348 to 473 K for PS. The solubility increased with increasing pressure and decreasing temperature. At 438 K and 2 MPa, the solubilities of butane and isobutane in PP were 0.15 and 0.11 g‐gas/g‐polym, respectively. At 423 K and 2 MPa, the solubilities of butane and isobutane in PS were 0.08 and 0.05 g‐gas/g‐polym, respectively. Solubility could be correlated with the Sanchez‐Lacombe equation of state with temperature‐dependent binary interaction parameters to within 4.4% average relative deviation. Henry's constant for these gases in the PP and PS obtained in this work were used to determine correlation equations along with literature data. Polym. Eng. Sci. 44:2083–2089, 2004. © 2004 Society of Plastics Engineers.  相似文献   
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