1. Atropine is known to diminish bronchomotor tone. In order to investigate the acute effect of atropine on respiration and alveolar gas mixing, a dose of 2.4 mg was given intravenously. 2. Ten normal male volunteers were each studied three times with a nitrogen washout method, once before administration of atropine and then 20 min and 60 min thereafter. 3. After the administration of atropine ...

In recent years, impinging streams have received increasing interest for their high efficiency in heat and mass transfer. This numerical study was conducted to investigate flow and heat transfer characteristics of one-way opposing jets of non-Newtonian fluids. Effects of Reynolds number impinging angle, momentum ratio and flow behavior index on mixing index were evaluated. The results showed im...

We study mixing of two fluids of different viscosity in a microfluidic channel or porous medium. We show that the synergetic action of alternating injection and viscous fingering leads to a dramatic increase in mixing efficiency at high Péclet numbers. Based on observations from high-resolution simulations, we develop a theoretical model of mixing efficiency that combines a hyperbolic mixing mo...

in recent years, impinging streams have received increasing interest for their high efficiency in heat and mass transfer. this numerical study was conducted to investigate flow and heat transfer characteristics of one-way opposing jets of non-newtonian fluids. effects of reynolds number impinging angle, momentum ratio and flow behavior index on mixing index were evaluated. the results showed im...

in this paper, numerical investigation of a flat passive micromixer with heterogeneous surface properties that the flow through it, is driven by the electroosmotic flow have been presented. the governing equations, which consist of a laplace equation for the distribution of external electric potential, a poisson equation for the distribution of electric double layer potential, modified navier-s...

In many microreactors, reactant flows are split into many lamination segments and then fed into the reactor to enhance mixing efficiency. This feeding method is applied since mixing in microreactors is mainly driven by diffusion because of low Reynolds and thus the mixing time is proportional to the square of diffusion length. The mixing efficiency of reactants greatly influences the product co...

A simple method for measuring the efficiency of expired air mixing devices is described. Preliminary studies comparing a number of mixing chambers indicate that the bag-inbottle system is the most efficient. The dependence of mixing efficiency on VT, f and expired flow rate is demonstrated. Two types of mixing failure are distinguished. The clinical implications are discussed, including those r...