Temperature-controlled environment

Scales win always perform better in a temperature-controlled environment this is particularly important for high precision balances. Those designed to automatically recaHbrate as conditions change will perform better in less-than-ideal conditions. 

Graebing P, Chib JS (2004) Soil photolysis in a moisture- and temperature-controlled environment. 2. Insecticides. J Agric Food Chem 52 2606-2614... 

In Differential vapour sorption a sample of material is placed on an accurate balance in a temperature controlled environment where the humidity of the gas phase can be accurately controlled. The adsorption and desorption behaviour of the sample is quantified with respect to water and hysteresis phenomena are identified. 

Samples constructed from adherends which had been alkaline cleaned, lubricated or left untreated exhibited similar joint strength values and durability trends (Figure 10). Adhesive joints placed in the room temperature control environment or the 23 C water bath retained lOOZ and 92% of initial joint strength, respectively. Failure remained cohesive within the adhesive for all of the control samples and for the first 20 days of exposure in the 23 C water bath. After 20 days, some failure began to initiate at both the primer/steel and primer/topcoat interfaces. The adhesive/topcoat interface proved to be more durable than those found between the substrate/primer/topcoat layers. Samples exposed to the more severe salt fog, 60 C water bath and cycle tests were able to retain 70% to 50% of their initial strength over a 60-day exposure period. 

A typical thermocouple installation for an industrial application is shown in Fig. 6.23. Instead of placing the reference junction in a temperature controlled environment (which is often inconvenient), an automatic reference junction compensation circuit is fitted. This provides a second source of emf Sj,° in series with the thermocouple emf E. The meter thus measures 0 = E 0 where E%-0... 

The principles underlying the operation of the chromatograph and its use in a commercial separation process are discussed in Volume 2, Chapter 19. In this section emphasis is placed on its function as an on-line process analyser in which form it consists of three major subdivisions (apart from any electronic readout system), viz. the sampling assembly, the chromatograph column and the detector. All three are generally contained within the same temperature-controlled environment (Fig. 6.50). 

Graebing, P, M.P Frank, and J.S. Chib (2003). Soil photolysis of herbicides in a moisture- and temperature-controlled environment. J. Agric. Food Chem., 51 4331 -337. 

The current method of determining the energy properties of polyurethane is the Dynamic Thermal Mechanical Analyzer (DTMA). This instrument applies a cyclic stress/strain to a sample of polyurethane in a tension, compression, or twisting mode. The frequency of application can be adjusted. The sample is maintained in a temperature-controlled environment. The temperature is ramped up over the desired temperature range. The storage modulus of the polyurethane can be determined over the whole range of temperatures. Another important property closely related to the resilience, namely tan delta (8), can also be obtained. Tan (8) is defined in the simplest terms as the viscous modulus divided by the elastic modulus. 

Sonication is a simple method for reducing the size of liposomes and manufacture of nanoliposomes (21, 22). The common laboratory method involves treating hydrated vesicles for several minutes with a titanium-tipped probe sonicator in a temperature-controlled environment as explained in the following section. 

MT Maintain between 60 and 80°F Continuously monitor and alarm if out Material must be in temperature-controlled environment at least 24 hours prior to use in production... 

Meltdown An empirical measure of the rate at which ice cream melts when exposed to warm temperatures, usually determined by measuring the amount of melted ice cream that drips through a wire mesh as a function of time in a temperature-controlled environment. 

Some rubber compositions, for example those containing reactive chlorine, can promote the surface corrosion of metals in contact with them, and in certain applications this can be sufficient to impair component performance. To guard against the use of such materials, a test method is described in ISO 6505 (BS903. Part A37). The procedure is similar to that for contact stain, in that a. sandwich of rubber and test surface, in this case a specified metal, is stored under load in a temperature-controlled environment for a given period. The measurement is a visual one and includes an indication of the ease of separation of the test rubber and the metal at the conclusion of the test. 

Joule heating leads to zone spreading and both qualitative and quantitative irreproducibility to attenuate Joule heating the column is housed in a temperature-controlled environment. Unregulated... 

A phase reaction is always accompanied by an enthalpy change (section 2.12), and this heat effect can readily be observed if a cooling curve is plotted for the system. In many cases a very simple apparatus can be used. A large glass test-tube, fitted with a stirrer and a thermometer graduated in increments of 0.1 °C and held in a temperature-controlled environment, will often suffice. The temperature of the system is recorded at regular intervals of say 1 min. 

For the accounting of promastigotes adhered to the membrane, the membrane extraction medium was performed by washing with a saline phosphate solution with pH 7.0 for the disconnection of protozoans, in a totally sterile and temperature-controlled environment. Subsequently, the membranes were reintroduced in order that the adsorption process is restarted, until the next third hour counting. 

TMA uses a LVDT to measure the linear displacement of the sample held in various probe configurations shown in Figure 17.80, to measure softening by penetration, expansion/ contraction, tension and dilatometry. The sample is held in a temperature controlled environment and the sample temperature is measured with a thermocouple in close proximity to the sample. The probe displacement is plotted against sample temperature or time. 

The Meissner rheometer utilizes a horizontal sample supported on a gas cushion in a temperature-controlled environment, which is then drawn horizontally by metal belts moving in opposing directions. It yields precise quantitative measures of tensile extensional viscosity to large stretches. It is somewhat difficult to use, however, and it is limited to low strain rates. 

Placing the electrochemical detector in a temperature-controlled environment, preferably together with sample injector and column, can improve the noise and drift of the system as shown in Table 3. 

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