Room Temperature Tightness Test

Recent advances have led to the development of the Room Temperature Tightness Test known as ROTT.l" This test closely resembles the actual operating cycle of the gasketed joint (i.e., loading and unloading). It generates parameters that are used to calculate the bolt load for a required maximum allowable leak rate. Gasket manufacturers publish ROTT data. 

Seal off offtake 2 and spill metallic zirconium into section 5 via offtake 6. Tightly close offtake 6 with a rubber stopper. Connect the apparatus via offtake 8 to a vacuum system for 15-20 min. Next place test tube 1 into a Dewar vacuum flask with liquid nitrogen and seal off offtake 6. Perform this work wearing eye protection in the presence of your instructor ) After the pressure in the system becomes equal to 10 mmHg (in about 40-60 minutes), seal off offtake 8. Stop cooling test tube 1 and wait until the apparatus acquires room temperature. 

Method. A 0.5-ml volume of 2 N potassium hydroxide is added to the sample residue in a test-tube which has a screw cap lined with PTFE. The cap is placed tightly on the tube and the contents are heated at 110 °C for 20-30 min. The tube is cooled to room temperature and 0.5 ml of hexane is added. The test-tube is then capped and shaken. 

This test is performed to determine the amount of cyanide in the sample that would react with chlorine. Not all cyanides in a sample are amenable to chlorination. While HCN, alkali metal cyanides, and CN- of some complex cyanides react with chlorine, cyanide in certain complexes that are tightly bound to the metal ions are not decomposed by chlorine. Calcium hypochlorite, sodium hypochlorite, and chloramine are some of the common chlorinating agents that may be used as a source of chlorine. The chlorination reaction is performed at a pH between 11 and 12. Under such an alkaline condition, cyanide reacts with chlorine to form cyanogen chloride, a gas at room temperature, which escapes out. Cyanide amenable to chlorination is therefore calculated as the total cyanide content initially in the sample minus the total cyanide left in the sample after chlorine treatment. 

To prepare the silica gel (Anasorb, 130-140 mesh, Analabs, Inc.) for use, a portion is placed in an evaporating dish and baked overnight at 275° in a clean oven (15 g, for example, will fill five columns). Longer heating is permissible. When removed from the oven, the gel is immediately poured into a small bottle which is then tightly capped and allowed to cool to room temperature. Activated gel is not allowed to stand more than a day prior to use. Unused gel can be reheated. Hydrocarbon-free nitrogen is tested as part of column blank measurement. 

Empty capsule shells are stored at room temperature in tight containers that maintain a constant, adequate relative humidity. The Deutsche Arzneimittel Codex (DAC) describes the test for dissolution of capsule shells empty... 

To a solution of Ni(cod)2 (10 mol%, relative to nitrile), PCys (40 mol%) and nitrile in toluene was added 1,3-diene (4.0 equiv.). The resulting mixture was transferred into a pressure-tight test-tube (volume 8.5 mL). The test-tube was tightly sealed up and thermostated at 130°C for a giving time. After the reaction mixture was cooled to room temperature, all volatiles were removed in vacuo. NMR yields of the crude product were determined by NMR analysis using 1,3,5-trioxane, 1,4-dioxane or... 

Fig. 38 Evolution of /m, the J-Integral accounting for the fracture toughness, and of the elongation at break, break> as a function of the long period, LP, (left) and the lateral size of /3-crystals, L300, (tight). Tests have been performed at room temperature on injection molded samples at 1.5 ms to determine /y and at 50mmmin to measure Sbreak-Mechanical and structural responses have been varied by varying the concentration of NU-lOO, the nucleating agent from 0 to 1300 ppm...

In this paper, the term loosely cross-linked network will be used to denote the network formed by the reaction of the 6,300 g/mol advanced resin with DADPS. This resins was also tested after allowing the sample to age at room temperature for 90 d. The term tightly cross-linked network will be used for the epoxy resin formed by the reaction of the DGEBA monomer with DADPS. 

The carefully bred strains of animals used for toxicology testing may be much more uniform in their responses, but they are more sensitive to environmental stresses than their wild cousins. Temperature, humidity, and airflow in the animal quarters must be tightly controlled and adjusted to the optimum value for the individual species. Ventilation in the animal rooms should be equivalent to 12 to 15 changes per hour without drafts on the animals. 

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