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J E Graf

Publications and source records attributed to J E Graf.

3 recordsLinked to original sources
PubMed1976

Analysis of bromide ion in wine by ion selective electrode.

The use of the bromide ion selective electrode for the determination of bromide ion in wine has been found to be rapid and reliable. The method has been used for still wines and carbonated wines and is applicable to all wines regardless of their country of origin. The method consists of treating a 50 ml aliquot of wine with 2 ml each of 3.75M H3PO4, saturated KNO3, and 1M CuSO4. After 10 min the electrodes are immersed in the samples and a millivolt reading is obtained. One hundred mul 500 ppm bromide ion standard is added and the millivolt reading is taken. Bromide ion concentration in the wine equals (Cdelta x 1)/((antilog deltaE/S)-1) where Cdelta equals 1, deltaE equals the change in potential expressed in millivolts, and S equals the electrode slope.

Bromides↗
PubMedDate not supplied

Sequential pulse defibrillation for implantable defibrillators.

A technique is described that reduces defibrillation threshold for automatic implantable defibrillators, permits either reducing the size of the pulse generator or increasing the effectiveness of the pulse generator, and provides an increased safety factor. Defibrillation threshold was compared in 12 anesthetized dogs with mean (+/- SD) body weight of 21.6 +/- 3.4 kg for two defibrillating modalities: 1) single pulse technique with current flowing from electrodes in the right ventricle to electrodes either in the superior vena cava or on the left ventricular epicardium, and 2) sequential pulse technique. The sequential pulse technique tested uses two pulses and three or four electrodes. Current of the first 5-ms pulse flows from the superior vena caval electrode to an electrode in the right ventricle, and after a 1-ms interval, current of the second pulse flows from electrodes on the left ventricular epicardium to the right ventricular electrode. Ventricular defibrillation threshold was reduced by 56% to 6.3 +/- 1.03 joules (mean +/- SEM) (P less than 0.01). Because defibrillation threshold is less for sequential pulse defibrillation than for conventional techniques, sequential pulse defibrillators can be smaller and more effective than previously available devices.

Animals↗