Cooling testing standards

Cloud Point This is the temperature at which a cloud or haze of wax crystals appears when a fuel or lubricant is cooled under standard test conditions. 

The cooling rate showed no appreciable effect on flavor scores and was eliminated as a variable in subsequent tests. Since there was some indication of a tendency toward texture deterioration on rapid cooling, a standard method of cooling to 4°C. followed by vapor phase cooling (essentially slow) to irradiation temperature was followed in subsequent studies designed to measure the effects of the other variables more accurately. 

The concentration of the material contained in the hydrocarbon that leads to the deposition of wax crystals may vary from very small percentages up to substantial amounts. The concentration will affect the so-called "cloud point" which is the temperature at which crystals first appear in the solution that is cooled under standard test procedures. Clearly this temperature will be of considerable significance in fouling by crystallisation of hydrocarbon wax, on cooled heat exchanger surfaces. Of less importance, but still relevant to the fouling process, is the so-called "pour point". The pour point, a temperature lower than the cloud point, is the temperature at which liquid does not flow under prescribed test procedures. Both the cloud point and pour point are empirical measurements useful for comparing the properties of different crude oils. 

Lubrication of the test pieces is now standard practice in order to eliminate one obvious source of variation. The more uniform flattening of the test piece also eases measurement of thickness after release from compression. However, there remain specifications in which set is determined in the absence of lubricants. It has also become common practice with general-purpose rubbers to measure compression. set after just one day at 70°C, which for sulfur-vulcanized elastomers can be a. sensitive measure of the state of cure. Higher test temperatures are specified for special-purpose and speciality synthetic rubbers, but the one-day test has remained popular, not least as a cla.ssification criterion and grade requirement in such specifications as ASTM D2000 and the British Standard series of material specifications for individual rubber types. Tests seldom last more than seven days, and recovery is usually confined to the standard. 30 minutes after release, during which time the test piece cools to standard laboratory temperature if taken from an oven. The short-term nature of the test and the absence of isothermal conditions during recovery has been questioned by Birley and other workers [43]. 

As mentioned above, NNSA had organized to establish technical documents before the licensing procedure started. The second document, namely the Standard Content and Format of the Safety Analysis Report of the lOMW High Temperature Gas-cooled Test Reactor, which defines the content framework of the Preliminary Safety Analysis Report of the lOMW High Temperature Gas-cooled Test Reactor (PSARy, has guided the compilation of the document. 

Institute of Nuclear Energy Technology, Tsinghua University. Standard Content and Format of the Safety Analysis Report of the lOMW High Temperature Gas-cooled Test Reactor, 1993... 

Reagents used include 500 ml concentration sulphuric acid in an automatic dispenser (5 ml volume), 500 ml 5% phenol solution and standard sucrose solution (lOmg/lOOml). Select a series of 15 X 18 mm glass test tubes which are clean and free from dust or cellulose fibres. In the first step take 0.1 ml of 80% ethanol extract and add 0.9 ml of water, simultaneously adding 1 ml of 5% phenol. Pump a jet of 5 ml of concentrated sulphuric acid to the central part of the sample and mix (Carefiil this step is potentially dangerous, and solution comes to the boil.) A face mask must be worn, and acid must be added behind the screen in the fume hood. Measure the optical density at 490 nm when the tubes have cooled, and standardize the procedure with standard of sucrose (5-70 pg per tube). The amount of ethanol soluble sugar in kernels of Nonpareil almond is between 2.5 and 3.5mg/g. 

Standard Practices for Simulated Service Testing for Corrosion of Metallic Containment Materials for Use With Heat-Transfer Fluids in Solar Heating and Cooling Systems Standard Test Method for Corrosion of Steel by Sprayed Fire-Resistive Material (SFRM) Applied to Structural Members... 

If required, actual temperatures can be adjusted to the relevant test standards using fans or cooling. According to ISO 4892 [198], the less accurate black standard temperatures are still permitted, but are losing in relevance [214]. 

Fluid Specifications. The performance characteristics of all antifreeze solutions are governed by fluid specifications, that have been developed over the years by industry standards committees, such as the American Society for Testing and Materials (ASTM) and the Society of Automotive Engineers (SAE). Additionally, most engine and/or cooling system manufacturers have thek own compositional specifications to which the fluids must conform. 

It is recommended that performance tests be specified and conducted in accordance with the Cooling Tower Institute procedure, as this gives the process engineer a standard of reference. Most cooling tower manufacturers are members of this Institute. 

Laboratory tests used in the development of inhibitors can be of various types and are often associated with a particular laboratory. Thus, in one case simple test specimens, either alone or as bimetallic couples, are immersed in inhibited solutions in a relatively simple apparatus, as illustrated in Fig. 19.34. Sometimes the test may involve heat transfer, and a simple test arrangement is shown in Fig. 19.35. Tests of these types have been described in the literatureHowever, national standards also exist for this type of test approach. BSl and ASTM documents describe laboratory test procedures and in some cases provide recommended pass or fail criteria (BS 5117 Part 2 Section 2.2 1985 BS 6580 1985 ASTM 01384 1987). Laboratory testing may involve a recirculating rig test in which the intention is to assess the performance of an inhibited coolant in the simulated flow conditions of an engine cooling system. Although test procedures have been developed (BS 5177 Part 2 Section 2.3 1985 ASTM 02570 1985), problems of reproducibility and repeatability exist, and it is difficult to quote numerical pass or fail criteria. 

The catalogue-rated cooling capacity of a room air-conditioner, if not qualified, will be based on ASHRAE Standard 16-1983. This specifies test conditions of air onto the evaporator at 80°F dry bulb, 50% relative humidity (26.7°C, 49.1% saturation), and air onto the condenser at 95°F dry bulb, 75°F wet bulb (35°C and 23.9°C). The original basis for this specification was the ambient condition prevailing in the mass-market area of the USA. 

Pipette 25 mL of an aluminium ion solution (approximately 0.01 M) into a conical flask and from a burette add a slight excess of 0.01 M EDTA solution adjust the pH to between 7 and 8 by the addition of ammonia solution (test drops on phenol red paper or use a pH meter). Boil the solution for a few minutes to ensure complete complexation of the aluminium cool to room temperature and adjust the pH to 7-8. Add 50 mg of solochrome black/potassium nitrate mixture [see Section 10.50(C)] and titrate rapidly with standard 0.01 M zinc sulphate solution until the colour changes from blue to wine red. 

Procedure. Prepare four test solutions of phenol by placing 200 mL of boiled and cooled distilled water in each of four stoppered, 500 mL bottles, and adding to each 5g of sodium chloride this assists the extraction procedure by salting out the phenol. Add respectively 5.0, 10.0, 15.0 and 20.0 mL of the standard phenol solution to the four bottles, then adjust the pH of each solution to about 5 by the careful addition of 5M hydrochloric acid (use a test-paper). Add distilled... 

The injector temperature should be determined by the nature of the sample and the volume injected, not by the column temperature. When analyzing biological or high-boiling samples, clean the injector body with methanol or other suitable solvent once per week. Install a clean packed injector liner and a new septum, preferably near the end of a workday. Program the column to its maximum temperature, then cool the column and run a test mixture to check the system using standard conditions. 

Ninhydrin Assays. Ninhydrin tests were performed using a modified procedme of Taylor et al. " APS Silica (10-75 mg) of various loadings (0.857, 0.571, and 0.343 mmol NH2/g Silica) was added to phosphate buffer (5 mL, 100 mM, pH 6.5), and 1 mL of a 5% w/v solution of ninhydrin in ethanol was added to the sluny. After stirring for an hour in a boiling water bath, the mixture was allowed to cool slowly to room temperature. The silica was then filtered and washed three times with 70°C distilled water. The filtrate was collected, added to a volumetric flask, diluted to 100 mL, and the absorbance of this solution at 565 mu was measured using a UV-visible spectrophotometer. The reference solution was prepared as above with unmodified amine-free silica. Calibration standards were prepared with aliquots of a 1 mg/mL solution of APS in ethanol. 

The inner surface of a vial is treated with the insecticidal coating by introducing a measured volume, usually 5 or 10 ml., of standard solution or tissue extract and placing the vial in an air bath oven at 70° C. with care to avoid local overheating until the volume is reduced to about 1 ml. The vial is then removed and rolled by hand while the remaining solvent evaporates, care being taken to secure an even distribution over the sides and bottom. As soon as the vial is cool, the cover is put on with the open hole over the vial. Flies or other test insects may then be introduced as desired. 

Standard test for hydrolytic stability. The hydrolytic stability of the chlorinated resins was determined by the following test procedure. An acid digestion autoclave having a volume of 125 ml is charged with 40 ml of resin and 28 ml of deionized water. The bomb is sealed and transferred into an oven, pre-heated to 200 °C. The test is continued for 24 hours. The bomb is removed and cooled to ambient temperature. The liquid is separated from the resin and the chlorine content analyzed while the resin is washed thoroughly and its acid capacity is determined as described in section 5. The test results are shown in Table 2. 

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