Resistance changes

Filled-bulb temperature sensors are also widely used. An inert gas is enclosed in a constant-volume system. Changes in process temperature cause the pressure exerted by the gas to change. Resistance thermometers arc used where accurate temperature or diflcrcntial-temperature measurement is required. They use the principle that the electrical resistance of wire changes with temperature. 

Chromite is used in steel works as a refractory material for lining and repairing basic hearth furnaces. In its resistance to corrosion, and durability, it is superior to magnesite and silica-alumina mixtures. It vithstands sudden temperature changes, resists abrasion, and its hardness is but little affected at high temperatures. 

Counters such as the Coulter Counter determine the number of particles in a known volume of an electrolyte solution. The suspension is drawn through a small orifice that has an electrode on either side. The dispersed phase particles interfere with current flow, causing the resistance to change. Resistance changes are related to the particle volume. 

Ria giant Reagent Note Cone. Temp. Time PDL Rating % Weight Change Resistance Note. ... 

The treatment of nosocomial pneumonia requires aggressive therapy with careful consideration of the dominance and susceptibility patterns of tbe pathogens present within the institution. The epidemiology of these common pathogens should be evaluated on a regular basis to identify changing resistance patterns and subsequent alternation of treatment guidelines. 

Weigh cells or load cells are typically used to measure the mass of the contents of a vessel. These are electromechanical devices which convert force or weight into an electrical signal. The technique is to construct a wheatstone bridge similar to that used in the RTD circu it with one resistor being a rheostat which changes resistance based on load. 

Hypertension results from an increase in transniural pressure across the vessel wall. The primary determinants of vascular tension are the more muscular arterioles, which are able to change diameter and thus change resistance. Thus, total peripheral resistance (TPR) is the primary determinant of hypertension. The amount of fluid within the vessels is also a determinant. Therefore, cardiac output and blood (fluid) volume are also determinants. Recall also that cardiac output = heart rate x force of contraction and is influenced by preload (venous tone) and afterload (arterial tone). 

A thermistor is made of a fused mixture of metal oxides. As the temperature of the thermistor increases, its electrical resistance decreases (as opposed to the bolometer). This relationship between temperature and electrical resistance allows thermistors to be used as IR detectors in the same way as bolometers. The thermistor typically changes resistance by about 5% per °C. Its response time is also slow. 

Temperature transducers The most common temperature sensor is a thermocouple made from two different metal wires. As the temperature changes, so does the relative resistance of the wires, giving a signal proportional to the temperature. Thermistors are semiconductors with the property of changing resistance with temperature. 

Under ambient conditions, SWNTs are p-type semiconductors. This means that the charge carriers are holes, or the absence of electrons. This class of semiconductors shows an increase in conductivity when electron density is withdrawn and a decrease in conductivity when electron density is donated. This behavior has been observed experimentally for individual SWNTs connected to a set of electrodes. This allows for chemical detection with a simple chemiresistor. This is a device composed of two electrodes which are connected by some material, in this case a single-walled carbon nanotube, which changes resistance upon exposure to a particular analyte. 

Temperature Change of properties - strength change - resistivity change - ductility change - colour change... 

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