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Zn1-xMgxSeyTe1-y layers have been grown on (100) ZnTe substrates by low-pressure metalorganic vapor phase epitaxy using dimethylzinc, bis-methylcyclopentadienyl magnesium ((MeCp)2Mg), diethylselenide and diethyltelluride as source materials. The Mg mole fraction of Zn1-xMgxSeyTe1-y layer can be controlled successfully by varying (MeCp)2Mg transport rate. P-type doping of this material has been tried using tris-dimethylaminophosphorus as a dopant source. The influence of annealing temperature or dopant transport rate upon the electrical property has been investigated. All the layers show p-type conduction even without annealing. Through this study, a maximum carrier concentration of 2.5×1018 cm−3 is obtained.

Objective To determine the time-specific effects of mono-n-butyl phthalate (MBP) on the transabdominal migration of the testis in fetal rats. Materials and methods Three groups of pregnant rats were administered MBP by stomach-tube feeding when the fetus was at 7–10 days of gestation in group 1, 11–14 days in group 2, and 15–18 days in group 3; controls (group 4) were given vehicle only from 7–18 days. At 20 days of gestation the fetuses were obtained by Caesarean section, and the position of the testes, the development of the gubernaculum, cranial suspensory ligament and the epididymis were examined. Results The timed intervals of MBP administration showed that the maximum inhibition of transabdominal testicular descent was at 15–18 days of gestation. There was an elongated gubernaculum and hypertrophic cranial suspensory ligament in the MBP-treated rat fetuses. Furthermore, the epididymis showed a few small ducti deferentia, although there were no remarkable changes in either the Sertoli and Leydig cells in these testes. The mean (sem) content of testicular testosterone was significantly less (P

Polysilanes having hydroxyl and related functional groups have been synthesized by the electroreduction of appropriate dichlorosilanes with Mg electrode, and a vinyl polymer which has oligosilane unit in the side chain has also been synthesized.

The electroreduction of polyacrylamide derivatives in DMF using tetraalkylammonium salts (R 4 NX) as supporting electrolytes has been found to yield the corresponding anionic species possessing interesting reactivities as electrogenerated bases (EGBs). The homopolymer of n -methylacrylamide (MAAm) and its copolymers with N , N -dimethylacrylamide (DMAAm) and styrene (St) were used as polymeric probases and the reactivity of the resulting polymer EGBs was investigated. The polymer EGB prepared from the copolymer of MAAm with DMAAm [copoly(MAAm-DMAAm)] containing 65% of MAAm unit gave the best result in the trichloromethylation of α, β-unsaturated esters (89%). It was also found that polymeric probases were easily recovered by reprecipitation and they were repeatedly useable as probases.

Dilute magnetic semiconductors and wide gap oxide semiconductors are appealing materials for magnetooptical devices. From a combinatorial screening approach looking at the solid solubility of transition metals in titanium dioxides and of their magnetic properties, we report on the observation of transparent ferromagnetism in cobalt-doped anatase thin films with the concentration of cobalt between 0 and 8%. Magnetic microscopy images reveal a magnetic domain structure in the films, indicating the existence of ferromagnetic long-range ordering. The materials remain ferromagnetic above room temperature with a magnetic moment of 0.32 Bohr magnetons per cobalt atom. The film is conductive and exhibits a positive magnetoresistance of 60% at 2 kelvin.

We report on the magnetic properties of an oxide-diluted magnetic semiconductor (DMS), Zn0.64Mn0.36O. The temperature dependence of the magnetization shows a spin-glass behavior with the large magnitude of the Curie–Weiss temperature, corresponding to a stronger antiferromagnetic exchange coupling than other II–VI DMSs. The small effective Mn moment (x∼0.02) under high field also represents a strong antiferromagnetic exchange coupling in this compound.

Dual damascene Cu interconnects with Keff below 2.0 have been demonstrated for the first time. Air gaps between Cu lines were formed with a low K SiOC film in a carefully designed manner. CoWP cap layers were introduced to protect the Cu lines and to eliminate a dielectric liner layer. In addition, AGE (Air Gap Exclusion) was applied to solve crucial problems related to the air gaps. Keff of 1.9 was obtained at 65 nm design rule, which surpassed by far ITRS target (2.5~2.8) for hp 45. It was also confirmed that leakage current between lines was suppressed by the formation of the air gaps.

The electroreduction of alkylaryldichlorosilane carried out with Mg cathode and anode in a single compartment cell gave high molecular weight poly(alkylarylsilane) (M(n) = 5200-31000, M(w)/M(n) = 1.4-1.8) in 5-79% yield. The effects of electrode material, monomer concentration, amount of supplied electricity, and ultrasound were investigated. This electroreductive method was also successfully applied to the synthesis of polygermanes, silane-geramane copolymers, and also poly[p-(disilanylene)phenylenes].

The stepwise elongation of Si-Si chain was achieved by the electroreductive cross-coupling reaction of chlorohydrosilanes with dichlorooligosilanes. The electroreductive polymerization of the resulting dichlorooligosilanes using Mg electrodes is highly promising for the synthesis of sequence-ordered polysilanes. Dichlorotrisilanes were found to be good monomers for the electroreductive synthesis of the polysilanes, units of which are ordered in three sequences.

Boschniakine, C10H11NO, and boschnialactone, C9H14O2, were isolated as the physiologically active principles of Boschniakia rossica Hunt, and their absolute structures have been determined. Four optically active stereoisomers of boschnialinic acid (2-carboxy-3-methylcyclopentylacetic acid), one of which is an oxidation product of boschnialactone, have been synthesized and their stereochemistries established.

Die Thioether (I) reagieren in einer Eintopfreaktion mit den Aldehyden (II) unter elektroreduktiver Kupplung zu den Lactonen (IIIa)-(IIId).

Bei der im Titel erwahnten Reaktion entstehen β-Hydroxynitrile (IV), (VI) und (VIII), und β-Hydroxycarbonsaureester (X).

Aus den cyclischen Aminen (I) erhalt man bei der elektrochemischen Methoxylierung die α-substituierten Amine (II), die mit den Phenylhydrazinen (III) zu den substituierten lndolen (IV) fuhren.