Speed rating

Flow processes iaside the spinneret are governed by shear viscosity and shear rate. PET is a non-Newtonian elastic fluid. Spinning filament tension and molecular orientation depend on polymer temperature and viscosity, spinneret capillary diameter and length, spin speed, rate of filament cooling, inertia, and air drag (69,70). These variables combine to attenuate the fiber and orient and sometimes crystallize the molecular chains (71). 

Higher efficiency at any speed rating, particularly medium and low speeds. 

Table 3-26 gives the specific speeds for various centrifugal pump types. Table 3-27 gives the suction specific speed ratings for single-suction and double-suction centrifugal pumps. These tables are for pumps handling clear water. 

Note. Rigid couplings are not designed to absorb variations in torque and speed and should not be used in such applications. Maximum in-service coupling speed should be at least 15% below the maximum coupling speed rating. 

Capacity = amount of water absorbed speed = rate of water removal intensity = level of water remaining after drying, that is, high means that the smallest amount of free water remains after drying. 

Fig. I. Relationship between concurrent measurements of the rate of ammonia loss made using the wind tunnel and micrometeorological mass balance methods during an experiment in which the mean air speed through the tunnels was adjusted to maintain a value within 20% of the mean ambient wind speed. Rates of loss measured using the wind tunnels are the means of four replicates, the bars around each point indicating the 95% confidence limits (reproduced from ref. 12).

Fig. 31. HPLC chromatogram of the mixture obtained when using Ratz s procedure for the synthesis of NjPsCMeAzlg (Waters Liquid Chromatograph Instrument, (t Bondapack Cie reverse phase, pure methanol, RI detection, speed rate = 1 cm/mn) A = NaPjfMeAzIg, B = N3P3(MeAz)sCl, C = NaPjCMeAzl Oj...

ISO is the speed rating of the film as per factory specifications, determined through controlled testing El is any speed other than the factory spec ISO that you choose to use. 

Choose the best speed for the pump. Analyze the specific speed and suction specific speed at each of the various operating speeds using the data in Tables 6.20 and 6.21. These tables show that at 870 and 1160 r/min, the suction specific-speed rating is poor. At 1750 r/min, the suction specific-speed rating is excellent, and a turbine or mixed-flow type of pump will be suitable. Operation at 3500 r/min is unfeasible because a suction specific speed of 26,000 is beyond the range of conventional pumps. 

A process is said to be spontaneous if it occurs without outside intervention. Spontaneous processes may be fast or slow. As we will see in this chapter, thermodynamics can tell us the direction in which a process will occur but can say nothing about the speed (rate) of the process. As we will explore in detail in Chapter 15, the rate of a reaction depends on many factors, including temperature and concentration. In describing a chemical reaction, the discipline of chemical kinetics (the study of reaction rates) focuses on the pathway between reactants and products in contrast, thermodynamics considers only the initial and final states and does not require knowledge of the pathway between the reactants and products (see Fig. 10.2). 

Capacity amount of water taken up. Speed rate of water absorption. 

Suppose a driver travels 40 miles in an hour we describe his average speed (rate) as 40 mi/h. This does not necessarily mean that he drove at a steady speed. He might have stopped at a few traffic signals, made a fuel stop, driven sometimes faster, sometimes slower—his instantaneous rate (the rate at which he was traveling at any instant) was quite changeable. 

An irreversible process involves the natural movement of a system from a non-equilibrium state to an equilibrium state without intervention, thus it is a spontaneous process. Basically thermodynamics can tell us the direction in which a process will occur, but can say nothing about the speed (rate) of the process. Onsager might be counted as the founder of the field with his papers from in 1931 entitled Reciprocal relations in irreversible processes, Phys. Rev., vol. 37, pp. 405-426 Phys. Rev., vol. 38, pp. 2265-2279. 

Predictions of changes in productivity are difficult in part because a major cause of probable climate change is increasing atmospheric carbon dioxide, which is also the raw material for photosynthesis. Enriching the atmosphere with CO2 could potentially speed rates of photosynthesis and, thereby, increase agricultural production. Indeed, laboratory experiments in which CO2 concentrations were increased from 300 to 600 ppm, increased photosynthetic rates by 20% in maize and 60% in wheat (Akita and Moss, 1973). Laboratory experiments also show that enrichment with CO2 increases the growth of root shoots and increases tire efficiency of water use. 

Time is the particular instant at which a structure exists or a process occurs, or the measured or measurable period over which a structure endures or a process continues. For the study of all aspects of living systems as we know them, for the measurement of durations, speeds, rates, and accelerations, the usual absolute scales of time—seconds, minutes, days, years—are adequate. A concrete system can move in any direction on the spatial dimensions, but only forward— never backward—on the temporal dimension. 

A positive or negative kinetic cooperativity occurs with a burst" or lag". Burst" is the conformational change of the enzyme (after addition of the substrate) to the form with the lower activity and lag" is the opposite change, in which an increase of the initial speed (rate) is registered. The slow transitions ( bursts" or lags" ) are found at the beginning of the reaction before the steady-state is achieved (9). 

The osmotic pressure of a solution is unaffected by the membrane used. The only assumption we make is that the membrane allows solvent to pass but not solute. However, the equation says nothing about the speed (rate) at which the movement of solvent occurs. The speed will be dependent upon the type and dimensions of the membrane. 

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