Control of dissolved gases, especially oxygen and carbon dioxide, is an essential component of intensive water reuse systems. Control of both dissolved oxygen and carbon dioxide concentrations is typically carried out by means of gas transfer processes, although chemical processes are also used to control carbon dioxide concentration. Theoretical and practical considerations of oxygenation and ...

Northern Hemisphere's carbon dioxide emissions. "That's much more than any terrestrial plant ecologist would have considered likely," Tans said. Conserving tree and plant populations, he added, might raise their carbon dioxide uptake even higher. Understanding how carbon cycles through plants is vital to decreasing global warming. By burning fuel and clearing forests, human activity generates 7...

We present three patients with respiratory failure in whom conventional mechanical lung ventilation resulted in unacceptably high levels of carbon dioxide, severe acidosis and high vasopressor requirements. A pumpless arteriovenous extracorporeal carbon dioxide removal device (Novalung) was inserted. Arterial carbon dioxide levels were reduced rapidly with a corresponding increase in pH, reduct...

The metabolism of rat retina was found to be sensitive to the concentration of the carbon dioxide-bicarbonate buffer system. Increasing the carbon dioxide from 1 per cent to 5 per cent at constant pH nearly doubled both respiration and glycolysis. Increasing the carbon dioxide at constant pH from 5 per cent to 20 per cent had no effect on glycolysis, but depressed the Q(O(O2) ) from 31 to 19. I...

For the purpose of estimating a very small amount of carbon dioxide in general biological problems, two pieces of apparatus have been already described.* The principle of the apparatus is as follows : 1. Exceedingly minute quantities of carbon dioxide can be precipitated as barium carbonate on the surface of a small drop of barium hydroxide solution. 2. When a drop of barium hydroxide is expose...

In dogs anaesthetized with either halothane or chloralose cardiac output was measured at three levels of arterial carbon dioxide tension. As the carbon dioxide tension was raised there were significant increases in cardiac output. After the administration of a selective cardiac beta-receptor blocking agent (practolol) there were no significant changes in cardiac output as the carbon dioxide ten...

We have studied 14 female patients undergoing elective laparoscopy under general anaesthesia with peritoneal insufflation of carbon dioxide in order to examine changes in physiological deadspace (VDphys), arterial to end-tidal carbon dioxide partial pressure difference (PaCO2-PE' CO2) and PaCO2. VCO2 increased after insufflation of carbon dioxide with a mean (SD) maximum increase of 32 (28)% co...

Assessment of blood gas status is important in the management of patients with chronic pulmonary disease. Arterial puncture is often painful and may damage the arterial wall. Measurement of oxygen saturation by transcutaneous oximetry offers a non-invasive alternative to arterial methods but does not allow assessment of partial pressure of carbon dioxide. We have examined the value of oximetry ...

We have examined the cerebrovascular response to carbon dioxide during normotension, sodium nitroprusside (SNP)-induced hypotension and high dose isoflurane-induced hypotension in 10 patients who received a standardized general anaesthetic. Carbon dioxide reactivity was determined by varying PaCO2 between 3.0 and 8.0 kPa and recording simultaneously blood flow velocity from the middle cerebral ...

Field experiments were conducted to test ideas for fossil fuel carbon dioxide ocean disposal as a solid hydrate at depths ranging from 349 to 3627 meters and from 8 degrees to 1.6 degrees C. Hydrate formed instantly from the gas phase at 349 meters but then decomposed rapidly in ambient seawater. At 3627 meters, the seawater-carbon dioxide interface rose rapidly because of massive hydrate forma...