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There is a very narrow two-phase region in the CdS-CdTe pseudobinary system in high temperature, and we can obtain mixed crystals in almost the entire range of composition. Lattice parameters of CdSxTe1-x satisfy “Vegard's law”. Both of the solidus and the liquidus curves determined by D.T.A. have the same minimum temperature of 1071°C at x=0.2. At 1000°C the crystal structure is the cubic zincblende (x<0.2) and the hexagonal wurtzite (x>0.2). In the solid phase there is a miscibility gap, and it is attributed to lattice strain resulting from the large difference in atomic sizes of the VIth elements. On account of the strain energy contributions to the thermodynamic free energy the solidus curve is calculated from the experimental liquidus curve, and it agrees very well with the experimental data.

A single crystal of β‐normalSiC was grown by chemical vapor deposition using an SiH4‐C3H8‐H2 system on a silicon substrate with a sputtered layer. The grown layer of 4 μm thickness was confirmed as a single crystal by examination with reflection electron diffraction and x‐ray diffraction. To reduce the large mismatch between β‐normalSiC and a silicon substrate, a sputtered β‐normalSiC layer was employed as a buffer layer. Even though the sputtered layer was polycrystalline, the subsequent layer deposited by CVD was a single crystal. The crystallinity of the deposited layer was strongly affected by the thickness of the sputtered layer, the substrate temperature during sputtering, and the temperature of chemical vapor deposition.

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Poly(vinyl alcohol) (PVA) of various molecular weight (MW=10,560-116,600) was successfully labeled with fluorescein isothiocyanate isomer I (FITC) according to the method of de Belder and Granath. A high-performance size-exclusion chromatographic procedure was developed for the quantitative analysis of FITC-labeled poly(vinyl alcohol) (F-PVA) in biological samples. F-PVA (80 K) disappeared slowly from the blood circulation according to the first-order kinetics (t1/2=7 h) after intravenous injection to rats. A dose-independent behavior of F-PVA (80 K) was observed in the blood circulation, in the tissue distribution and in the urinary and fecal excretions. This suggested that PVAs are eliminated exclusively by the mechanisms that do not involve saturable transport processes. Furthermore, it was found that PVAs are very stable in the body because no degradation product was detected in the urine and feces. 125I-labeled poly(vinyl alcohol) (125I-PVA) was prepared by introducing tyramine residues to the hydroxyl groups of PVA molecules by the 1,1'-cabonyldiimidazole (CDI) activation method. 125I-PVA (80 K) was retained in the blood circulation for several days after intravenous injection to mice. Although the tissue distribution of PVAs was small, a significant accumulation into the liver and the spleen was observed. Fluorescence microscopic examination of paraffin section of the liver revealed that F-PVA (80 K) was endocytosed by the liver parenchymal cells. 125I-PVA (80 K) captured by liver was slowly transported via the bile canaliculi and gall bladder to the intestine and excreted in the feces. It was suggested, therefore, a long time is necessary for 125I-PVA (80 K) to be excreted perfectly from the body.

The concept of random-switching control, by whch the switching-noise spectrum is smoothed and its level is reduced, is proposed. Two types of control circuits realizing the random switching are introduced, and its effectiveness is codinned by the experimental results of switchmg-noise spectrum.