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The effect of maternal hemorrhage in chronic preparations was studied on fetal lambs in the last month of gestation. Fourteen to 20 per cent of maternal blood was estimated to have been removed within 30 minutes, which resulted in a drop of 30 per cent of mean maternal arterial pressure. A fetal bradycardia started 28 ± 13 minutes after the beginning of maternal hemorrhage. It lasted 30 ± 15 minutes and was concomitant with a rise in fetal arterial pressure. It was followed by a long-lasting fetal tachycardia of 130 ± 38 minutes and was corrected only by reinfusion of blood to the mother. The fetal blood gases demonstrated a mild asphyxia with a persistent metabolic acidemia until reinfusion of blood to the mother. Maternal and fetal plasma cortisol levels rose significantly at the end of the hemorrhage. Tracheal fluid flow did not change. Fetal breathing recorded 20 hours before and 24 hours after the experiment did not show consistent changes, but during fetal bradycardia there was no fetal breathing. Recent clinical investigations in this field have been made in the human fetus to estimate standards of fetal well being. These peculiar animal experiments do not show any significant improvement by recording fetal breathing over the recording of prelabor fetal heart rate.

One of the primary obstacles to be overcome for the development of economical fuel cells is the high cost of the membrane electrolyte. The currently favoured polymer electrolytes consist of poly(tetrafluoroethylene) backbone structures and poly(perfluorosulphonic acid) side chains. In an effort to find lower cost membranes, some radiation-grafted copolymer membranes were investigated. All the membranes contained poly(styrenesulphonic acid) side chains. Three different backbone polymer structures were studied: low-density poly(styrene), poly(tetrafluoroethylene)/poly(perfluoropropylene), and poly(tetrafluoroethylene). The results indicate that the membrane consisting of a poly(tetrafluoroethylene)/poly(styrenesulphonic acid) copolymer is a promising candidate as a fuel-cell electrolyte.

We have constructed a negative-electrode material system that provides an abrupt voltage change near the end of discharge, providing a clear marker for the voltage vs state of charge (SOC) relationship. Distinctive voltage features during the operation of a battery enable an accurate state estimation of the cell, and thus efficient energy and power management as well as health assessment. The approach we have developed should be useful for lithium-ion batteries with cell voltages remaining nearly constant over a large SOC range such as cells constructed with graphite negative electrodes and iron phosphate positive electrodes. Specifically, we describe the incorporation of a lithium titanate (LTO) material into a substantially graphitic negative electrode so as to provide a distinctive voltage change at a preselected SOC. A simple analytic procedure based on juxtaposing open-circuit potential curves is shown to represent well the combined system open-circuit potential, thereby confirming the efficacy of the approach. Fabricated full cells comprising lithium iron phosphate positive and carbon–LTO negative electrodes are used to demonstrate the effectiveness of the concept in a battery.

The Cd‐Te codeposition process has been investigated in situ by photoresponse measurements.

consisting of GaCl3, 1‐methyl‐3‐ethylimidazolium chloride, and AsCl3is studied over the potential range 0 to ‐2V relative to an aluminum reference electrode.

A radiotracer technique is developed for the simultaneous, quantitative analysis of all mobile species within a perfluorinated ion‐exchange membrane (Nafion 117), the most promising membrane material available for fuel cells.