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161.
An artificial compound eye corresponding to apposition eyes of insects has been demonstrated using a two-dimensional array of gradient-index rod lenses known as a Selfoc lens plate (a SLP). A single erect Moiré image is reconstructed from a number of inverted micro-images by an experimental optical system composed of the SLP, a pinhole array and a plano-concave lens. Characteristics of the compound eye is briefly discussed from the viewpoints of space-bandwidth product, viewing angle, and focal depth. Capability of a scale-invariant image sensor that has been proposed as an application of the compound-eye-type imager was also proved experimentally.  相似文献   
162.
We consider thek-stability ofm-quota games ofn players. We prove that anm-quota game (N, v), which satisfies the conditionv(S)=0 for allS, ¦S¦ ≤m ?1, is (m ?1)-stable if and only if there is no weak player. Further, some relationships between ak-stable pair and anm-quota are shown. Some ofLuce's results [1955] on Shapley quota games are generalized tom-quota games.  相似文献   
163.
6N(N-formyl-D-phenylalanyl)-deoxyamino--cyclodextrin and 6N(N-formyl-L-phenylal-anyl)-deoxyamino--cyclodextrin (I andII) were prepared. These new hosts formed intramolecular host-guest complexes and included naphthyl derivatives preferentially with a stoichiometry of 1:1. The inclusion behavior was different between I and II because the cavity shape formed with the CD cavity and the phenylalanine moiety of I was different from that of II.  相似文献   
164.
Thin films of hollandite-type K1.9Ga1.9Sn6.1O16 (KGSO) were prepared by a spin-coating method. The films were colorless and transparent, 100-150 nm thick, and consisted of KGSO fine particles of about 20 nm in average size. The adsorption behavior of NO on the KGSO surface was examined by diffuse reflectance infrared fourier transform (DRIFTS). The KGSO was preheated at 968 K in a gas mixture of N2 and O2 prior to NO adsorption. As the oxygen ratio in the gas mixture increased up to 40%, absorption bands emerged and became stronger around 1400 cm-1. Those bands were assigned to NO2 species in chelating and nitrito form. It was found that the coexistence of oxygen remarkably improves the adsorption ability of NO on KGSO surface.  相似文献   
165.
Effects of aging and oxidation on positronium formation in polyethylenes   总被引:1,自引:0,他引:1  
Positron annihilation lifetimes (PAL) have been measured for polythylenes (PEs) under differenr conditions of heat treatment. It is shown that the intensity, I3, of the long-lived component of positronium (Ps) shows hystereses between the heating and cooling processes due to aging effect. It is also shown that about half of Ps observed at low temperatures below the glass transition is inhibited after the sample is heat-treated above the melting point in the atmosphere containing oxygen. It is suggested that carbonyl groups (C=0) formed by thermal oxidation can inhibit Ps formation through trapping the precursors of Ps, e+ and/or e-.  相似文献   
166.
A kinetic approach to the polymer reaction, with KOH as catalyst, between ethanol and poly(p-vinylphenyldimethylsilane) containing silicon–hydrogen as a functional group on the side chain was carried out. The rate equation was obtained by measuring the initial rate of the model reaction as v = k[KOH] [SiH] [EtOH] in benzene and v = k[KOH] [SiH] in methyl ethyl ketone. It was observed that the rate of reaction was affected by the polarity of the solvents. In the polymer reaction the rate constant decreased markedly with increasing ethanol concentration. A change of viscosity of the polymer in various solvents was observed to have a good correlation with the decrease in reaction rate in corresponding solvents. In mixed solvents, consisting of both good and poor solvents for the polymers, the reaction rate depended upon two factors, the entanglement of the polymer chain and the polarity of the solvents. The equivalent globular model of the polymer chain is suggested for study of the polymer reaction. A schematic local-distribution curve of the reaction species is proposed.  相似文献   
167.
A new nonenzymatic formation of ATP from ADP was observed in the presence of cyclodextrin in a phosphate buffer of pH 7.00 at 37.0°C under at mospheric conditions. Time conversion curves were obtained in the presence of -cyclodextrin and heptakis-(2,6-dimethyl)--cyclodextrin. The effect of adding -cyclodextrin, MgCl2, phosphate buffer and creatine was examined kinetically as well as the effect of cyclohexanol as an inhibtor.  相似文献   
168.
The treatment of (5,5-dimethyl-3-oxo-1-cyclohexenyl)iminotriphenylphosphorane ( 2 ) with phenyl isocyanate ( 3a ) gave N-(5,5-dimethyl-3-oxo-1-cyclohexenyl)-N'-phenylcarbodiimide ( 4a ) in situ. The reaction of 4a with enamines proceeded smoothly to afford the pyridine ring formation with the elimination of amine. This means that 4a is regarded as a new class of 2-aza-1,3-butadiene. The scopes and limitation of this reaction are also discussed.  相似文献   
169.
The adsorption and recovery of ionic surfactants, such as dodecylbenzenesulfonic acid (DBS) and benzalkonium chloride (BKC), from an aqueous solution were studied using the β-cyclodextrin polymer (β-CDP). BKC always demonstrated a higher adsorption efficiency than DBS in batch tests, isotherms, and column tests. The adsorption characteristics of the surfactants seemed to be caused by inclusion into β-CD, and they were easily determined using the Langmuir adsorption isotherm. Furthermore, the surfactants adsorbed by β-CDP were easily released by shaking it with a mixture of water and methanol. Recovery efficiency was dependent on the mixture ratio of the solvent, and regenerated β-CDP was reusable as an adsorbent.  相似文献   
170.
New oligosaccharide-branched -cyclodextrins having a various oligosaccharides in a primary hydroxyl group of -cyclodextrin(CD) were synthesized and examined for the interaction with the immobilized concanavalin A(ConA) compared with 6-O-glucosyl and maltosyl CD. Oligosaccharides were converted to lactones at the reducing end, which was connected with 6-monoamino--CD forming an amide bond. For the analysis of the interaction between ConA immobilized on an aminosilane-hydrogel surface and various oligosaccharide CDs, a biosensor of the FISONS IAsys apparatus based on a resonant mirror detector (RMD) was used. As a result, it interacted with immobilized ConA and both maltosyl--CD(3) and maltosyl--CD(6), and glucosylglucono-amide--CD(7) with the association constants, Ka of 134, 833 and 8730 M–1, respectively.  相似文献   
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