Pure water pyrex glass

Author has introduced the discovery of mechanolysis, a novel phenomenon of water splitting [9,10], which has been understood as a result of frictional electricity between the Teflon stirring rod and the Pyrex glass of the beaker, where pure water containing semiconductor powder is filled. Author [9] has pointed opt that the semiconductor must have the property of the hopping conductivity, and called tribolysis. There exists another type of mechanolysis, which may be due to the piezo electrolysis. This type is called piezolysis, but not discovered yet. 

Fig. 12.2 Time dependencies of sonophotocatalytic reaction products from pure water. As powdered photocatalyst, Ti02-A (200mg, Soekawa, Commercial Reagent, rutile-rich type and specific surface area 1.9 m2/g) was used without further treatment. Liquid water (150 cm3, Wake, Distilled water for HPLC was used as reactant and was purged with argon, a Pyrex glass bulb (250-300 cm3) was used as a reactor and was placed m a temperature-controlled bath (EYELA NTT-1200 and ECS-0) all time. After the glass bulb was sealed, the irradiation was carried out under argon atmosphere at 35°C. Photo and ultrasonic irradiations were performed from one side with a 500 W xenon lamp (Ushio, UXL500D-O) and from the bottom with an ultrasonic generator (Kaijo. TA-4021-4611, 20C kHz 200 W), respectively.

A solution of 30 g. of KOH in 50 ml. of water is prepared 10 g. of KMnO t is added and the mixture is boiled in an open 250-ml. Erlenmeyer flask until a pure green solution is obtained. The water lost by evaporation is then replaced and the flask set in ice. The precipitated black-green crystals, which show a purplish luster, are collected on a Pyrex glass filter, washed (high suction) with some IN potassium hydroxide, and dried over P3O5. The salt can be recrystallized by dissolving in dil. potassium hydroxide and evaporating in vacuum. 

PES/PI 2080 Blends PES was dried for more than four hours at 150 C to remove residual water before use. Solutions (3 wt%) of the blends were prepared by dissolving the two pure polymer constituents in the desired ratio. Films of the blends were cast from these solutions on Pyrex glass dishes at 80-90°C under vacuum. To obtain solvent-free samples, the films were gradually heated to 240-250 C over a period of three days. To obtain samples of varying solvent contents, the films were dried at lower temperatures for shorter lengths of time. The solvent content of the samples was measured by themiogravimetric analysis. 

Mix 400 mL of pure concentrated hydrochloric acid with 250-400 mL of distilled water so that the specific gravity of the resultant acid is 1.10 (test with a hydrometer). Insert a thermometer in the neck of a 1 L Pyrex distillation flask so that the bulb is just opposite the side tube, and attach a condenser to the side tube use an all-glass apparatus. Place 500 mL of the diluted acid in the flask, distil the liquid at a rate of about 3-4 mL min-1 and collect the distillate in a small Pyrex flask. From time to time pour the distillate into a 500 mL measuring cylinder. When 375 mL has been collected in the measuring cylinder, collect a further 50 mL in the small Pyrex flask watch the thermometer to see that the temperature remains constant. Remove the receiver and stopper it this contains the pure constant boiling point acid. Note the barometric pressure to the nearest millimetre at intervals during the distillation and take the mean value. Interpolate the concentration of the acid from Table 10.5. 

In a 5-I. round-bottom flask (Pyrex) is placed a mixture of 500 g. of phthalic anhydride and 400 g. of 28 per cent ammonium hydroxide. The flask is fitted with an air condenser not less than 10 mm. in diameter and is then slowly heated with a free flame until the mixture is in a state of quiet fusion at a temperature of about 300°. It requires about one hour before all the water has gone and about one and a half to two hours before the temperature of the reaction mixture reaches 300° and the mixture is a homogeneous melt. It is advisable, during the heating, to shake the flask occasionally some material sublimes into the condenser and must be pushed down with a glass rod. The hot reaction mixture is now poured out into a crock, covered with a paper to prevent loss by sublimation, and allowed to cool. The product is practically pure without further treatment, and melts at 23 2-23 5 °. The yield is 470-480 g. (94-95 per cent of the theoretical amount). 

Ground crystals of la (0.020 g, 0.042 mmol) were placed between two glass plates. The sandwiched sample was placed in a transparent polyethylene bag. UV irradiation was carried out externally on this sample with a 400 W high-pressure mercury lamp through a Pyrex filter for 6 h at ca. 23 °C in a water bath. Without purification, 2 a was obtained as a pure product in quantitative yield. The cycloadduct 2 a was recrystallized from hexane/ethyl acetate to give colorless crystals. Similarly other [4+4]photocycloadducts 2b-2h were obtained. 

Materials used in the preparation of buffer solutions should be good quality laboratory chemicals, purified if necessary as described in Chapter 8 and dried to constant composition. The distilled water used as solvent should have been recently boiled to remove dissolved carbon dioxide and have been protected from contamination by atmospheric carbon dioxide while cooling. (This precaution is unnecessary in preparing buffer solutions having pH values less than 5.) The water should have a specific conductivity of less than 2 X 10 ohm cm at 25°C. Solutions should be stored in stoppered Pyrex (or similar borosilicate glass) or pure polyethylene bottles. 

---