Infrared temperature probe

Vacuum combined with microwaving has been tried for embedding the tissue in paraffin, using Milestone s MicroMED LAVIS-1000 machine (Marani et al., 1996 Bosch et al., 1996). The advantage of this system is that microwaves travel with ease through a vacuum, whereas conventional heating under vacuum is difficult. This machine provides pressure reaching 100 hPa, and the microwave oven attains a maximum power of 1,000 W its cycle time can be adjusted between 0.1 and 0.5 sec. The machine is equipped with an infrared temperature probe which allows temperature control from outside the unit. 

Sample Custodians determine from the COC Form whether a temperature blank has been enclosed with the samples. If a temperature blank has been enclosed, Sample Custodians remove the ice, the packing material, and the samples from the cooler and line them up on a receiving table or in a fume hood, if samples emanate odor. They measure the cooler temperature by inserting a thermometer into the temperature blank. If the blank is not present, they measure the temperature inside the cooler by placing a thermometer or an infrared temperature probe between sample containers. The temperature of the cooler upon arrival to the laboratory should be 2-6°C whether it has been measured inside the cooler or in the temperature blank. To document sample conditions upon arrival at the laboratory, laboratories record the cooler temperature on the COC Form or use a separate cooler receipt form, similar to one shown in Appendix 17. Samples are then placed in storage refrigerators or walk-in coolers kept at 2-6°C. 

An infrared temperature probe with a laser pointer that reads up to 500°F. 

Previous research has characterized the temperature variations observed in the nozzle by using specialized thermocouple arrays, costly infrared temperature probes, or intricate fixturing. While past studies have developed novel methods for measuring melt temperature, the present work focuses on interpreting data from commercially available temperature probes used for measuring melt temperature in the injeetion molding process. 

The temperature distribution is not only a function of radius, but also depends on the stellar luminosity, the disk geometry, and may depend on the accretion rate (see Table 8.1 and Section 3.3) for example, at a given radius irradiated flared disks will be warmer than flat disks. Naturally, hotter stars will heat their disks to higher temperatures at a given radius thus, mid-infrared spectroscopy probes different radii in different disks. 

The elements of an infrared melt temperature sensor are a sapphire window, an optical fiber, and a radiation sensor with associated signal-conditioning electronics as shown in Fig. 4.17. IR melt temperature probes are commercially available [85, 86] and fit in standard pressure transducer mounting holes. Because the sapphire window is flush with the barrel or die, the sensor does not protrude into the polymer melt. As a result, the sensor is less susceptible to damage, there is no chance of dead spots behind the sensor, and the melt velocities are not altered around the sensor. When melt velocities are changed, the melt temperatures will change as well. Therefore, the melt temperatures measured with an IR sensor are less affected by the actual measurement than with an immersion sensor. 

This is perhaps one of the most difficult operations in mixing, and there have been no particular advances here for many years. Two types of tliermocouple have, and are still being, used. The first, and most widely used, utilises a strong thermocouple probe fitted with a thermocouple junction, and extending into the mixing chamber at some point. The second type is an infrared temperature measurement system, fitted to the mixer body to see into the mixing chamber. 

At various times, the use and accuracy of infrared temperature measurement has been extolled. This is very far from the truth, and accuracy and consistency has not been seen to be any better than the conventional thermocouple. Because of the requirements for a crystal window , location of an infrared thermometer has to be in one of the less severe mixing zones, resulting in a system life which is usually extended compared to conventional thermocouples. An infrared probe only measures a surface temperature the readings are therefore susceptible to the variations which can occur due to frictional heating of the mixing rubber surface, or alternatively to the effects of the cooled metal on the rubber surface from which it may have just parted. 

As a final example, similar spectroscopy was carried out for CO2 physisorbed on MgO(lOO) [99]. Temperatures were around 80 K and equilibrium pressures, as low as 10 atm (at higher temperatures, CO2 chemsorbs to give surface carbonate). Here, the variation of the absorbance of the infrared bands with the polarization of the probe beam indicated that the surface CO2 phase was highly oriented. 

Laser Raman diagnostic teclmiques offer remote, nonintnisive, nonperturbing measurements with high spatial and temporal resolution [158], This is particularly advantageous in the area of combustion chemistry. Physical probes for temperature and concentration measurements can be debatable in many combustion systems, such as furnaces, internal combustors etc., since they may disturb the medium or, even worse, not withstand the hostile enviromnents [159]. Laser Raman techniques are employed since two of the dominant molecules associated with air-fed combustion are O2 and N2. Flomonuclear diatomic molecules unable to have a nuclear coordinate-dependent dipole moment caimot be diagnosed by infrared spectroscopy. Other combustion species include CFl, CO2, FI2O and FI2 [160]. These molecules are probed by Raman spectroscopy to detenuine the temperature profile and species concentration m various combustion processes. 

Additional information concerning the mechanisms of solid—solid interactions has been obtained by many diverse experimental approaches, as the following examples testify adsorptive and catalytic properties of the reactant mixture [1,111], reflectance spectroscopy [420], NMR [421], EPR [347], electromotive force determinations [421], tracer experiments [422], and doping effects [423], This list cannot be comprehensive. Electron probe microanalysis has also been used as an analytical (rather than a kinetic) tool [422,424] for the determination of distributions of elements within the reactant mixture. Infrared analyses have been used [425] for the investigation of the solid state reactions between NH3 and S02 at low temperatures in the presence and in the absence of water. 

The SCR catalyst is considerably more complex than, for example, the metal catalysts we discussed earlier. Also, it is very difficult to perform surface science studies on these oxide surfaces. The nature of the active sites in the SCR catalyst has been probed by temperature-programmed desorption of NO and NH3 and by in situ infrared studies. This has led to a set of kinetic parameters (Tab. 10.7) that can describe NO conversion and NH3 slip (Fig. 10.16). The model gives a good fit to the experimental data over a wide range, is based on the physical reality of the SCR catalyst and its interactions with the reacting gases and is, therefore, preferable to a simple power rate law in which catalysis happens in a black box . Nevertheless, several questions remain unanswered, such as what are the elementary steps and what do the active site looks like on the atomic scale ... 

The strength of the Bronsted (BAS) and Lewis (LAS) acid sites of the pure and synthesized materials was measured by Fourier transformed infrared spectroscopy (ATI Mattson FTIR) by using pyridine as a probe molecule. Spectral bands at 1545 cm 1 and 1450 cm 1 were used to indentify BAS and LAS, respectively. Quantitative determination of BAS and LAS was calculated with the coefficients reported by Emeis [5], The measurements were performed by pressing the catalyst into self supported wafers. Thereafter, the cell with the catalyst wafer was outgassed and heated to 450°C for lh. Background spectra were recorded at 100°C. Pyridine was then adsorbed onto the catalyst for 30 min followed by desorption at 250, 350 and 450°C. Spectra were recorded at 100°C in between every temperature ramp. 

A sensitive probe of electrostatic interactions in the distal pocket is provided by the structural and vibrational properties of the Fe-CO unit [9], The bound CO ligand exhibits three main infrared (IR) absorption bands, denoted Ao, A, and A3, with vibrational frequencies 1965 cm-1, 1949 cm, and 1933 cm, respectively. These bands, which change relative intensity and wave-number depending on temperature, pressure, pH, or solvent [10], are used to identify functionally different conformational substrates of MbCO, denoted taxonomic substates [11], Nevertheless the relationship between the A states and specific structural features of the protein has not yet been clarified. 

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