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Collision activated dissociation (CAD) spectra and metastable ion (MI) spectra of the [C5H8O2]+· ions from various esters of angeric acid and tigric acid have been studied. The [C5H8O2]+· ions formed upon the McLafferty rearrangement from the precursor esters of these acids were identified as the same structures of the molecular ions directly produced by electron impact ionization of angeric acid and tigric acid respectively on the basis of CAD spectral evidence. The cis-trans isomerization of the acids can occur during ionization or subsequent fragmentation of the lower internal energy ions which proceed via unimolecular metastable decompositions. We have provided an example that the isomeric ions can be distinguished by the ion abundance enhancement by high energy collisional activation on the specific fragmentation reactions of the [C5H8O2]+· ions.

We demonstrate the ferroelectric behavior of PZT films grown on Si(111) substrates by using CeO 2 buffer layer. PZT (90 nm) films were prepared by electron beam assisted vacuum evaporation system and CeO 2 (27 nm) films were prepared by MBE (molecular beam epitaxy). It is found that a hysteresis is not shown in the capacitance-voltage ( c–v ) characteristics of CeO 2 /Si structures, whereas a hysteresis is obtained in the c–v plot of PZT/CeO 2 /Si structures, which is due to the ferroelectric nature of the PZT film. In addition, it is shown that the leakage current of PZT/CeO 2 /Si is as low as 10 −7 A/cm 2 at 8 V.

We report the crystalline quality and electrical properties of PbZr1-x TixO3 (PZT) films on Si substrates with epitaxially grown CeO2 buffer layers. CeO2 buffer layers were deposited by the electron-beam-assisted evaporation technique, and PZT films were formed by the sol-gel technique. It is shown that CeO2 buffer layers, which were epitaxially grown on Si(111) substrates at 500°C, effectively suppressed Si and Pb interdiffusion between PZT films and Si substrates. Furthermore, the capacitance-voltage and current-voltage properties of PZT/CeO2/Si indicated a ferroelectric nature and excellent breakdown strength.

An ultrasonic Doppler blood flow detection apparatus of the invention comprises: a transducing circuit for emitting ultrasonic waves at a predetermined interval and for receiving reflected ultrasonic waves from an object in the blood vessel and converting the received signal into an electric echo signal; a frequency-difference signal producing circuit for producing frequency-difference components between the echo signal and first pair of quadrature signals of a frequency f1 in response to the echo signal and the first pair of quadrature signals; first and second Doppler signal detection circuit for detecting first and second Doppler signals of upper and lower sidebands of the frequency f1 from the frequency-difference components in response to second pair of quadrature signals of a frequency f2; and a frequency difference calculation circuit for calculating frequency difference between output signals from the first and second Doppler signal detection circuits. The frequency difference indicates compressed Doppler shift frequency which can detect a higher velocity of blood flow.

The structures of the decomposing intermediate ions, [C7H8N]+ generated from a variety of toluidine and aniline derivatives were examined with the aid of kinetic energy release (KER).Among these ions, [C7H8N]+ ions generated from o-, m-, and p-toluidines and from 2, 3-, 3, 4-, and 2,6-xylidines are assigned to aminotropylium ion (a). The ions from o-, m-, and p-ethylanilines are interpreted as the corresponding aminobenzyl ion (b). A methyliminocy-clohexadiene ion structure (c) is postulated for the intermediate ion from N-methyl-o-, m-, and p-toluidines. The ion from N-ethylaniline is elucidated to be anilinomethene ion (d).These are in agreement with the results for the non-decomposing (stable) [C7H8N]+ ions, which were obtained by experimental heats of formation.

The geometry of a Hitachi RMU-7M double-focusing mass spectrometer was reversed by interchanging the positions of ion source and electron multiplier. The high resolution comparable to the “normal”instrument having Nier-Johnson type geometry can beobtained by using the modified instrument. This result makes it possible to measure metastable ion(MI)and collisional activation(CA)spectra and high resolution mass spectra on the same instrument by simple modification of the commercial instrument. The CA and MI spectra of the isomeric C8H8O+ ions generated from valerophenone and acetophenone were measured and discussed from a point of view of the ion structures.

Collisional activation spectra have identified (i) as Stable ion structures. Evidence is presented for a variety of pathway for their formation, including anchimeric assistance and hydrogen migration in less stable isomers. The fragmentation behavior of a number of [CnH2n+1O]+ isomers of n = 2 to 5 shows that extensive rearrangements are common, but that some reactions appear to be useful for ion structure elucidation. One reaction identified is unusual in that it represents the decomposition of an even-electron ion to yied an odd-electron ion product in significant abundance.

Reactions of 1-halo-1-nitroso- and 1-halo-1-nitrocycloalkanes with triphenylphosphine have been carried out. The Perkov reaction and Beckmann rearrangement occurred successively with the formation of lactams in high yields. The reaction of cycloalkanone oxime with halogen in the presence of triphenylphosphine also gave lactams in one step.

We have recently described1,2 a self-training interpretive and retrieval system (STIRS) for computer interpretation of mass spectra which utilizes directly data of all available reference spectra, and does not require prior spectra/structure correlations of these data either 'by human or computer effort. The computer selects different classes of data known to have high structural significance, such as characteristic ions, series of ions, and masses of neutrals lost, from the unknown mass spectrum, and matches these against the corresponding data of all the reference spectra. The reference compounds of closest match in each data class are examined for common structural features; criteria have been determined so that such features can 'be identified with approximately 95% relia'bility. Each reference compound has been coded in Wiswesser Line Notation (WLN) to make possible computer recognition of structural features. Further details of the initial system are available.1,2

An ultrasonic wave diagnostic apparatus having an array of electro-acoustic transducer elements and respective channels for supplying drive signals to the electro-acoustic transducer elements and amplifying received echo signals from these elements, with the respective overall gains of the channels being controlled by corresponding values of weighting data. A set of mutually independent D/A converters, smaller in number than the number of electro-acoustic transducer elements, produce weighting data for respective ones of the channels that are spaced apart by a fixed number of channels. Respective interpolated values of weighting data for the remaining channels are derived by analog operations executed upon each of successive pairs of D/A converter outputs.