What is the importance of cooperativity? That depends on the system, but let’s take hemoglobin. Hemoglobin’s mission is to pick up a large amount of oxygen in the lungs, where the oxygen concentration (or partial pressure) is about 100 torr, and then drop off a good fraction of it in the peripheral tissues where the oxygen concentration is about 20 torr. Cooperativity helps make this transport ...

Surface X-ray diffraction has been employed to elucidate the surface structure of α-Cr2O3(0001) as a function of water partial pressure at room temperature. In ultra high vacuum, following exposure to ∼2000 Langmuir of H2O, the surface is found to be terminated by a partially occupied double layer of chromium atoms. No evidence of adsorbed OH/H2O is found, which is likely due to either adsorpti...

The activation energies were calculated from oxygen consumption rates obtained from oxygen partial pressure (PO2) profiles in olfactory cortical slices of guinea pig in vitro, assuming that the Krogh coefficient varied linearly over the range of investigated temperatures (19-39 degrees C).

We studied, for the first time to our knowledge, transient stimulated Raman scattering in H(2)- D(2) and H(2)- CH(4) gas mixtures excited with 200-fs and 2-ps, 390-nm pulses. Depending on the composition and partial pressure, of those gases, we observed approximately 40 output lines simultaneously. Under optimum conditions a conversion efficiency of as much as 8% in the combination Raman line a...

The Gibbs-Bogoliubov formalism in conjunction with the pseudopotential theory is applied to the calculation of the vapour pressure of eight liquid metals from Groups I to IV of the periodic table and of alloys (Na-K). The calculated vapour pressure o f the elements and their temperature dependencies, the partial pressures, activities and boiling points of the alloys are all found to be in reaso...

We compare and contrast measurements of the mass accommodation coefficient of water on a water surface made using ensemble and single particle techniques under conditions of supersaturation and subsaturation, respectively. In particular, we consider measurements made using an expansion chamber, a continuous flow streamwise thermal gradient cloud condensation nuclei chamber, the Leipzig Aerosol ...

supported vanadia catalyst was successfully synthesized using wet impregnation of gamma-alumina to study propane oxidative dehydrogenation (pod). the prepared catalysts were characterized with xrd, bet, and tpr tests. in a broad temperature range (340 to 630°c), effects of vanadia loading (2.7, 5.4, and 9 wt%) and propane to oxygen ratio (3/1 to 1/3) were investigated on propane conversion as w...

In diffusion, gases (or liquids) move from an area of high concentration (partial pressure) to areas of low concentration (partial pressure). If there is a mixture of gases in a container, the pressure of each gas (partial pressure or concentration) is equal to the pressure that each gas would produce if it occupied the container alone. This applies equally well to the concentration of a gas in...

Through the detection of Coherent Population Trapping (CPT) resonances, we demonstrate the temperature-dependence cancellation of the Cs clock frequency in microfabricated vapor cells filled with a mixture of Ne and Ar. The inversion temperature at which the Cs clock frequency temperature sensitivity is greatly reduced only depends on the partial pressure of buffer gases and is measured to be l...

ALTHOUGH it is easy to measure anesthetic partial pressures in gas mixtures, it is not straightforward in blood. A single-step technique has been described,' but more commonly the sample is equilibrated in a water bath with a similar amount of air, and the partial pressure of the anesthetic in the gas phase is measured. The equilibration reduces the partial pressure of anesthetic in the Factor....