Electrically clamped

Martin, C. M., M. Ghadiri, U. Tuzun and B. Formisani, "Effect of the Electrical Clamping Forces on the Mechanisms of Particulate Solids, Powder Tech., 64, 1991, pp. 37-49. 

Martin, C. M., P. A. Arteaga, M. Ghadiri, and U. Tuzun, Characterization of the Single Contact Electrical Clamping Force," (pt. II), AICHE First Inteml. Particle Technology Forum, Denver, CO, Preprints, Aug. 17-19, 1994, pp. 77-82. 

If stress is kept constant this is called a mechanically free state. If, alternatively, the strain is kept constant this is spoken of as a mechanically clamped state. A similar terminology is sometimes used for the electrical situation (e.g. Cady 1964, p. 262). Keeping electric field strength constant is called electrically jree, while electrically clamped refers to the constancy of the electric flux density. Finally, keeping temperature constant is referred to as isothermal while the situation at constant entropy is called isentropic or adiabatic. 

The fourth arrd last pair of equations of state (independerrt variables D, and S ) cortesporrds to the combination of mechanically as well as electrically clamped piezoelectric element. Piezoelectric effect is described by the piezoelectric coefficient /r/ u. 

For a complete specification of mechanical compliances, it is necessary carefully to specify the conditions under which a given measurement is carried out thus, one must state not only whether it is 5 or T that is kept fixed, but also whether , or D, and whether, electrically free when D = 0, the crystal is said to be electrically clamped. The latter condition is not readily experimentally realized for details, interested readers are referred to Nye, (Oxford, 1957) Constancy of a components demands that the crystal be mounted so as to allow the strains to take place in as unhindered a fashion as possible the material is then mechanically free. Constancy of e components requires that, ideally, the crystal be firmly attached to a medium with infinite elastic stiffness the material is then mechanically clamped. 

Teflon stir bar 1 heavy duty balloon 1 roll of electrical tape Magnetic stirrer Support stand and clamps Ohaus triple beam scale 1 plastic funnel... 

Researchers at the MoneU Center (Philadelphia, Pennsylvania) are using a variety of electrophysical and biochemical techniques to characterize the ionic currents produced in taste and olfactory receptor cells by chemical stimuli. These studies are concerned with the identification and pharmacology of the active ion channels and mode of production. One of the techniques employed by the MoneU researchers is that of "patch clamp." This method aUows for the study of the electrical properties of smaU patches of the ceU membrane. The program at MoneU has determined that odors stimulate intraceUular enzymes to produce cycUc adenosine 3, 5 -monophosphate (cAMP). This production of cAMP promotes opening of the ion channel, aUowing cations to enter and excite the ceU. MoneU s future studies wiU focus on the connection of cAMP, and the production of the electrical response to the brain. The patch clamp technique also may be a method to study the specificity of receptor ceUs to different odors, as weU as the adaptation to prolonged stimulation (3). 

C. 3-Hydroxyquinoline. A 1-1. beaker is fitted with a thermometer and mechanical stirrer and clamped firmly on an efficient electric heater (Note 14). Diethyl succinate (400 ml.) (Note 15) is placed in the beaker and heated to boiling (215-220°) with stirring. 3-Hydroxycinchoninic acid (part B) (94.6 g., 0.5 mole) is added in portions to the boiling solution by means of a metal spoon or Scoopula. Care is taken to prevent too vigorous evolution of carbon dioxide. The addition requires 2-3 minutes, during which time a temperature drop is noted unless good heating is maintained. 

Most bonded repairs are cured using electric heat blankets and vacuum bags, shot bags or clamps for applying pressure. Programmable heat blanket controllers... 

When there is an electrical malfunctioning, a faulty plug is often the culprit. It should be replaced only by a plug able to stand up under industrial use. A clamp should be used to hold the plug to the wire. This will avoid strain on the connection in case the plug gets pulled out by the wire. If possible, wii e ends should be coated with solder before being attached. 

FIG. 17 Schematic illustration of the setup for a tip-dip experiment. First glycerol dialkyl nonitol tetraether lipid (GDNT) monolayers are compressed to the desired surface pressure (measured by a Wilhehny plate system). Subsequently a small patch of the monolayer is clamped by a glass micropipette and the S-layer protein is recrystallized. The lower picture shows the S-layer/GDNT membrane on the tip of the glass micropipette in more detail. The basic circuit for measurement of the electric features of the membrane and the current mediated by a hypothetical ion carrier is shown in the upper part of the schematic drawing. 

Electrophysiological Experiments. Guinea pig myocardial cells prepared as described previously 24) were superfused at 37 C with a Tyrode solution. Electrical properties of the myocytes were examined by the patch-clamp methods (25) using fire-polished pipettes. The current was measured by means of a patch-clamp amplifier, stored on the tape through a digital PCM data recording system, and analyzed with a computer. 

Space-clamped (HH) equations relate the difference in electrical potential across the cell membrane (V) and gating variables (0 < m, n, h < 1), for ion channels to the stimulus intensity (7J and temperature (T), as follows ... 

Four polarized ATR spectra can be recorded to characterize the three-dimensional (3D) orientation of a sample, p- and s-polarized spectra are recorded with the sample clamped with its Z- and X-axes sequentially aligned perpendicular to the incidence plane (that is, parallel to the s-polarized electric field). The absorbance measured in these different configurations is related to the anisotropic absorption indices of the sample, kj, as... 

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