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Higher catalytic activities have been found for RhX(CO)L2 complexes compared to the Rh4(CO)12–L system (molar ratio L:Rh 2:1) for the formation of ethylene glycol from synthesis gas.

A new method for the measurement of the differential energy distribution of exoelectrons by using a retarding potential has been developed in which the retarding voltage changes at the center of each channel of a multichannel analyzer. Within the first half interval of a channel, input pulses are added; within the second half interval, the input pulses are subtracted from the previously accumulated data. A differential energy distribution can be obtained after one scan of the retarding voltage. Using this method, differential energy distributions have been measured for thermally stimulated exoelectrons from a LiF single crystal and a BeO ceramics excited by UV light in an ultra-high vacuum.

Selective linear codimerization of terminal acetylenes and buta-1,3-diene catalysed by the first example of a dihydridotetrakis(trialkylphosphine)-ruthenium complex is reported.

To reduce the power consumption of a PLZT light shutter and the driving voltage change of it with the environmental temperature, we investigated the relation between halfwave voltage and temperature in various PLZT compositions. Compositions which showed a memory effect at room temperature showed large transverse quadratic electro-optic coefficients at temperatures higher than room temperature. We found these compositions required less power when the PLZT was kept at the higher temperature. A shutter consisting ofa PLZT with the composition 7.3/65/35 and an ITO heater showed low power consumption and a stable driving voltage when the PLZT was held at 100°C by the heater.

NN′-Disubstituted ureas were prepared under mild conditions in high yields from nitro-compounds using bromomagnesium alkyl- or aryl-amides and pentacarbonyliron.

An electro-mechanical transducer having a first layer made of piezoelectric material having opposing major surfaces, a pair of electrodes formed on the major surfaces of the first layer, respectively, and a second layer clamped at its one surface to one of the surfaces of the first layer. In this case, the first layer has a Young's modulus of E, the second layer has a Young's modulus Ex in one direction and a Young's modulus Ey in the direction perpendicular to the one direction in the major surface, the Young's moduli E, Ex, Ey satisfy the relation E>Ey, Ex>Ey, and one end of the first and second layers along the one direction is clamped. The thickness of the electrode is selected between 0.1 and 3 μm to obtain large amount of displacement at the other end. The outer surface of the electrode may be coated with a conductive paste to ensure voltage supply to the whole surface of the electrode.

The reaction of alkylphenylacetyl chlorides with aroyl chlorides catalysed by tetrakis(triphenylphosphine)palladium gives α,β-unsaturated ketones selectively via a decarbonylative cross condensation reaction.

We have prepared a 110 K superconducting phase as the dominant phase in the BiSrCaCu2O x ceramic by sintering at 865±5°C for 900 h in air. This superconductor has a resistance T c of 109.3 K and a structure containing stacking faults, as suggested by the broadened X-ray diffraction pattern. The volume fraction of the 110 K phase is as large as 28% by dc susceptibility measurements.

A new light-valve video projector using a PLZT light shutter linear array has been developed. A beam from a Xenon light source passes through the PLZT linear array and the resulting modulated beam is scanned vertically by a movable mirror and projected on the screen. PLZT shutters in the array are modulated with analog signals sampled from the video signal. Each shutter maintains its light intensity for the horizontal scanning period of 63.5 microseconds. The floating driving method can be used to maintain the driving voltage at the specified level because the PLZT light shutters have a memory effect similar to a capacitor. The PLZT shutters are separated from each other to eliminate crosstalk caused by stray capacity. The shutter array is made using the cutting method, which is described in detail.

N-(Trimethylsilyl)amines direct ring-opening carbonylation of a variety of cyclic ethers such as oxiranes (1–3), oxetane (4), tetrahydrofuran (5), and 1,3-dioxolane (6) in the presence of a catalytic amount of Co2(CO)8 under carbon monoxide pressure to give siloxy amides.

Dichlorotris(triphenylphosphine)ruthenium is highly active as a catalyst for the N-heterocyclisation of 2-aminophenethyl alcohols (2a–d) into indole derivatives in toluene under reflux, and the reactions proceed with spontaneous hydrogen evolution.

The exoelectron emission from stainless steel (types 304 and 430) has been investigated in an ultra-high vacuum system. A strong emission was detected at low and high temperatures for both samples. The intensity of exoelectrons emitted from color-treated film was weaker than that from bright annealed film. Samples from which bright annealed films had been removed, however, showed the strongest intensity at low and high temperature peaks. The mean energies at peak temperatures were measured by means of a retarding-field method. The mean energy obtained at high temperatures was lower than that at low temperatures. The this results shows that the exoelectron emission phenomenon can be used for monitoring the oxide films used to cover engineering-type materials.

The reaction of arylketenes with allyl acetates of allyl carbonates catalysed by tetrakis(triphenylphosphine)palladium selectively gives 1,3-dienes or allylated esters, respectively, in high yields.

Rhodium complexes having the unidentate anion of 2,4-pentanedione as a ligand have been synthesized by the reaction of [Rh(acac)(CO)2][Hacac = acetylacetone (2,4-pentanedione)] with highly basic tertiary phosphines. The X-ray crystallographic analysis revealed that the co-ordination chemistry about the Rh atom is square planar with two phosphine ligands in trans positions. The unidentate 2,4-pentanedionate ligand has a trans configuration with respect to the CC bond. Proton n.m.r. studies indicated a singlet resonance for the methine of the pentanedione anion, which is widely accepted as a proof of the cis configuration. In the i.r. spectra absorptions characteristic of the unidentate pentanedionate were observed in the 1 500–1 620 cm–1 region, but the ketonic absorptions were unusually low for αβ-unsaturated carbonyls.

The novel preparation of a wide variety of trans-[RhX(CO) L2] complexes (X = anionic ligand, L = tertiary phosphine) from [Rh4(CO)12], phosphine (L), and acid (HX) is described. A plausible formation pathway is proposed. The electron density on the phosphorus atom in trans-[RhX(CO)L2] decreases and the length of the Rh–P bond increases with an increase in the electronegativity of the anionic ligand, X, in a cis position to the phosphine ligand. The rhodium complexes (X = arylcarboxylate) are reduced to afford rhodate anions such as [Rh(CO)3L]– and [Rh (CO)4]– in hexamethylphosphoramide solution under CO–H2. The rate of reduction increases with a decrease in the electron-withdrawing effect of the arylcarboxylate ligand.