Reciprocating action

If many zones are present in the sample simultaneously, it may be advantageous to move the ampul (or heaters) slowly by one zone spacing, and then rapidly backward to catch the next zone. By such a reciprocating action, many zones can be moved continuously through the sample without a bank of heaters longer than the sample. 

Because of the reciprocating action of the piston, care must be exer-ci.sed to size the piping to minimize acoustical pulsations and mechanical vibrations. As a rule of thumb, suction and discharge lines should be sized for a maximum actual velocity of 30 ft/.sec (1,800 ft/min) to 42 ft/sec (2,500 ft/min). Volume 1 contains the necessary formulas for determining pressure drop and velocity in gas piping. 

Wechsel-winkel, m.pl. alternate angles, -wir-kung, /. reciproc action or effect, -zahl, /. number of changes or alternations, cycle number, frequency, -zersetzung, /. double (or mutual) decomposition. 

In the early 1960s efforts were made in the United States to operate vane motors and reciprocating motors with compressed air. The vane motors experienced some limited test success but were not competitive in the market of that day [84]. Out of these development efforts evolved the reciprocating (compressed) air hammers that have been quite successful and are operated extensively in the mining industry and have some limited application in the oil and gas industry [85]. The air hammer is not a motor in the true sense of rotating equipment. The reciprocating action of the air hammer provides a percussion effect on the drill bit, the rotation of the bit to new rock face location is carried out by the conventional rotation of the drill string. 

In a study where both peripheral and central nervous system effects were measured in rats co-exposed to u-hexane and toluene (Pryor and Rebert 1992), toluene exposure at 1,400 ppm for 14 hours a day for 9 weeks prevented the peripheral neurotoxicity (decreased grip strength and nerve conduction velocities) caused by exposure to 4,000 ppm 77-hcxanc alone. There was no reciprocal action of 77-hexane on the motor syndrome (shortened and widened gait and widened landing foot splay) and hearing loss caused by toluene. Brainstem auditory response amplitudes were decreased by 77-hcxanc, co-exposure to toluene did not block this effect. 

The noise due to the reciprocating action of the dual-headed pump in the 150C ALC/GPC has a constant frequency pattern and can be reduced by hydraulic filters as shown in Figure 3. A 60% reduction in the peak-to-peak noise is achieved by using a Mark II dampener (Laboratory Data Control, River Beach, Florida), while the M-45 filters under same conditions have reduced the noise by 90%. 

Figure 7.73 Schematic illustration of reciprocating action of injection molding screw. Reprinted, by permission, from A. B. Strong, Plastics Materials and Processing, 2nd ed., p. 424. Copyright 2000 by Prentice-Hall, Inc.

Frequency is the rate at which the reciprocating action is applied, in cycles/time. 

Tables are also used to wash coal. The reciprocating action of a table stratifies the high-gravity coal particles on the bottom and the low-gravity particles rise to the upper level of tine bed. As the low-gravity particles rise, they are moved across riffles that separate die high- and low-gravily material by the water flowing to the low side of the table deck. The refuse is trapped in the riffle troughs and the motion of the deck moves the refuse to discharge off the end.

Vp0) Volumetric concentration of the polymer X Reciprocal action parameter... 

When bags or other components are being made from flexible films or expanded materials (rigid like polystyrene, or flexible) it often is convenient to make cuts by means of a simple hot-wire device. Proprietary machines based on a reciprocating action are available for cutting flexible poly(vinyl chloride) films in quantity around patterns or templates. 

The reciprocating action pump shown in Figure 9.23 is the most common type in use, and it delivers a constant flow. The pulsations that result can be removed or lessened by damping, but a better solution has been the use of two heads out of phase with one another, as shown in Figure 9.24. Sophisticated, computer-designed camshafts have been built to minimize the pulsations from these pumps, and additional dampening is usually not required. 

Peyote seems to bring on synesthesia, a mixing and reciprocal action among the five senses, so that the drumbeat maintained throughout the ceremony evokes pictures in the head as it heightens aural sensations (see Osmond s description of drumming and his reaction in Psychedelics). 

Renard considers the formation of acetic acid as due to reciprocal action between the alcohol and carbon monoxide ... 

Iodine [ ] is a most useful medicine. The alteration in his water was Iodine removing some mischief from Liver, which had to be carried off by kidneys. There is intimate connection between liver and kidneys. When I had obstruction of gall-duct by gall-stone and jaundiced bile passed thro kidneys and bladder. There is reciprocal action between the 2 organs. 

It cannot rest at animal magnetism, i.e., the reciprocal action between animal and animal, nor with the plant, i.e., the reciprocal action between plant and plant, nor with the mineral, i.e., the reciprocal action between mineral and mineral. Rather it must end and begin with the naked body of the planet itself, with the elements, earth, water and air and their reciprocal working upon each other, whether it starts up above (with humans) or down below (with the body of the planet).42... 

Characteristics that disappear in reciprocal action must be opposed ones. Chemical combination presupposes that there are opposed characteristics in the elements, by dint of which such an inner penetration occurs that the result is the levelling out of the oppositions.17... 

Chemistry is the doctrine of reciprocal action of elements, which, on the one hand reveals itself as attraction and combination and, on the other hand, as repulsion and separation. The bearers of this reciprocal action are two sets of elements, differentiated by the name acids and alkali. Both these sets of elements confront each other as oppositions, i.e., as of quite different types. Characteristics that are missing in one set are present in the other, and those which are lacking in this one are present in the other, so that in fact they present chemical halves whose activity manifests itself as the striving to appropriate the lacking half and so to become a chemical whole.21... 

The book s subtitle named the process at work chemical reciprocal action . As was to be expected from a philosophically trained chemist, Runge expressed himself in dialectical terms ... 

The colours are isolated here and not isolated, they interpenetrate each other in their separation and separate out in their interpenetration. Such a thing can only be developed from the inside out as a natural growth. What are these pictures then They are natural formations, which arise through chemical reciprocal action.26... 

Fourcroy introduced a significant innovation in the French didactic tradition by fleshing out the operational foundation of theoretical chemistry. His definition of chemistry as a science which tries to discern the intimate reciprocal action of all the bodies of nature on one another was completely new, indicating his emphasis on operations and affinities rather than on principles. He also discussed analysis and synthesis only as the means of chemistry. True or simple analysis produced unaltered principles false or complicated analysis altered them. Synthesis or combination united different bodies by utilizing a force a tendency that existed between them. Although analysis and synthesis were often found united in the operations of chemistry, true analysis was quite... 

Reciprocal action of two soluble salts within a solution.—The phenomena of etherification, studied by Berthelot and Pdan de Saint-Giles, are not the only ones in which may be observed a state of chemical equilibrium, the common limit of two reactions which are the inverse of each other. Berthollet had predicted that such a state of equilibrium should be produced in a solution in which two soluble salts may, by double decomposition, produce two other soluble salts. Malaguti has verified the truth of Berthollet s prediction in the following way ... 

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