Watering trough, volume

The first law of thermodynamics states that energy may be converted between forms, but cannot be created or destroyed. Joule was a superb experimentalist, and performed various types of work, each time generating energy in the form of heat. In one set of experiments, for example, he rotated small paddles immersed in a water trough and noted the rise in temperature. This experiment was apparently performed publicly in St Anne s Square, Manchester. Joule discerned a relationship between energy and work (symbol w). We have to perform thermodynamic work to increase the pressure within the tyre. Such work is performed every time a system alters its volume against an opposing pressure or force, or alters the pressure of a system housed within a constant volume. 

The continuous light-water process developed by Hoechst [4] comprises five steps sulfoxidation, extract treatment, neutralization, distillation, and final treatment. Typically, the sulfoxidation proceeds in a trough-like reactor (1 in Fig. 2) of 55-m3 volume. The reactor has 40 UV lamps which are energized between 18 and 28 kW. 

In a typical experiment, a small volume of an insoluble surface-active material (dissolved in a water-insoluble solvent such as benzene) is placed atop a clean water surface. As the solvent evaporates away, a film remains and the moving barrier can be adjusted so that the surface film exerts pressure on the mica float. A calibrated torsion balance is used to measure the force that the film exerts on the float. That force divided by the length of the float is the force per unit length or the surface pressure. For studies of lipolysis kinetics , a Langmuir trough can be constructed so that one can measure lipase action under first-order and zero-order conditions. 

Pneumatic Trough device used to collect and measure the volume of gases invented in 1700s by Stephen Hales, consisted of glass container submerged in water in which gas displaced water... 

The small size and the particular design of the sample cells rendered the determination of pressure area characteristics in them impractical. Consequently, these characteristics were determined with a conventional trough (11). The solvent for the spin label solution was cyclohexane, and the volumes of spreading solutions used were 0.2-0.3 ml. These volumes were applied with a pipet by placing drops at various locations on the water surface. Techniques were checked by determining well known pressure-area curves such as steric acid. 

Following oral administration, lamivudine is absorbed rapidly with a bioavailability of about 80% in adults. Peak plasma levels average approximately 1000 ng/mL after 100-mg doses. Lamivudine is distributed widely in a volume comparable with total-body water. The plasma t,/2 of elimination averages about 9 hours, and approximately 70% of the dose is excreted unchanged in the urine. About 1% is metabolized to an inactive trawY-sulfoxide metabolite. In HBV-infected children, doses of 3 mg/kg per day provide plasma exposure and trough plasma levels comparable with those in adults receiving 100 mg daily. Dose reductions are indicated for moderate renal insufficiency (creatinine clearance <50 ml/min). Trimethoprim decreases the renal clearance of lamivudine. 

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