Kimax

Disposable syringe filter, 0.2-pm or 0.45-pm Round-bottom flasks, KIMAX Glass-wool... 

Graduated cylinders Kimax brand. Red Stripe, glass, 100- and 500-mL and 1-L HPLC sample vials HP Amber with Teflon/silicone/Teflon septa, capacity 2-mL Volumetric flasks, 200-mL... 

Thermal expansion of water and glass is discussed in Section 2-9. In contrast to older types of glass, volumetric glassware made of Pyrex, Kimax, or other low-expansion glass can be safely dried in an oven heated to at least 320°C without harm,16 although there is rarely reason to go above 150°C. 

Kimax glass, see Borosilicate glass Kirchoff vapor pressure equation, 284 Kovar ... 

Irradiations are carried out in Kimax glass ampoules. These ampoules are filled with 5 cc. of the solution, irradiated, using the apparatus previously described (7), and flame-sealed with a Perfe Keum Model HS-1 ampoule sealer. The irradiation source used for these experiments is a 1.3 X 106 curie cobalt-60 source consisting of two parallel plaques 56 inches wide by 48 inches high, spaced 16 inches apart. For most irradiations, the ampoules are placed in the center of a Masonite phantom which completely fills a No. 10 can (6 inches in diameter by 7 inches high). The can is placed in a fixed position in an aluminum carrier and transported into the irradiation cell to a predetermined position (5). The source is then elevated from the bottom of a 25-foot, water-filled pool into the irradiation position. After the desired exposure, the source is lowered to the bottom of the pool. 

Irradiation procedures. Mesophase solutions and neat solid samples of BN were prepared and sealed under N2 or vacuum in Kimax capillary tubes. Isotropic samples were either degassed (freeze-pump-thaw techniques) and sealed in pyrex tubes or saturated with N2 in pyrex tubes. Nitrogen was bubbled through the latter solutions during irradiation periods. When ther-mostatted, samples were placed in a temperature controlled ( 1°) water bath. All samples were irradiated with a 450 W Hanovia medium pressure Hg arc and were stored at -30°C until their futher use. Usually, a "dark sample was prepared and treated in an identical fashion to the irradiated samples except that it was shielded from the light. JSN from each tube was recovered by either column chromatography (silica or alumina and pentane eluant) at 4°C followed by solvent removal at 0°C and reduced pressure or by hplc (tr-hexane) at room temperature followed by solvent removal at 0°C and reduced pressure. Neat solid samples were dissolved in one of either benzene, tetrahydrofuran or toluene and were frozen until analyzed. 

Extraction of pesticides from wool Raw sheep wool both exposed and not exposed to pesticide diazinon (Dr Ehrenstorfer, Germany) methanol (BDH, NZ) 15ml glass tubes (Kimax, USA) acetonitrile... 

Many disposable glass laboratory items are made of soft glass. If a laboratory glass item does not specifically bear one of the words Pyrex , Kimax , or Duran in printed or raised letters, it is likely to be a soda-lime type of glass. 

In the following experiments use a 1.0 x 30.0 cm column containing a fritted glass base (Kimax 28570 or equivalent). 

Borosilicate glass is soda-lime glass to which boric oxide has been added. It is known under the brand names of Pyrex and Kimax . The addition of boron to the glass produces a product with superior durability, chemical, and heat resistance. 

In case of elastic linear brittle behaviour the straight line described by the experimental points runs through the origin (see Fig. 4(i)) and its slope gives Kimax (= Kic) [8-10]. 

Kimax (Fig- 5(ii), Kimax 3 MPa.m ) directly calculated from equation 1 for a/W = 0.5. The fracture resistance potentialities of the investigated material were therefore underestimated with the uncorrected values. 

Keff is always higher than Kimax- In the ductile range, Kjmax/Keff 0.70 0.03 for both grades whatever the test conditions. In case of unstable crack propagation, Kimax Ketr The values of Ken(iPP/EPR-l)/KeH(iPP/EPR-2) for given test conditions are close to those of Kimax(iPP/EPR-l)/Kimax(iPP/EPR-2) when both grades exhibit the same macroscopic behaviour. In other words, Kimax is a semi-quantitative toughness parameter, whereas Kefr provides a quantitative description of the fracture resistance. 

Indeed, as obvious from both exemples given in Fig. 2, the transition could thus be determined accurately within 0.1-0.2 decades of test speeds with few samples in a relative short time frame. Moreover, as the apparent values (Kimax) are always lower than the effective parameters (Keff), none of the material descriptor would be overestimated. In addition, since Kjmax-values have been shown to provide a semi-quantitative evaluation (in terms of test speed or temperature) of fracture resistance parameters, a coherent material comparison would be possible over the whole investigated range. This remark remains true as long as the grades have similar rp. For iPP grades, it should be checked (and considered with more caution) when materials exhibit different particle and matrix melt flow rates, or different crystalline structures. It should also be investigated in detail when different polymer families (ABS versus HIPS or rubber modified iPP) are compared. 

Glassware types include Class A and Class B. Class A glassware is manufactured to the highest tolerances from Pyrex, borosilicate, or Kimax glass (see tables on pages 41 and 42). Class B (economy ware) tolerances are about twice those of Class A. 

On a piece of weighing paper, thoroughly mix approximately 1 g of copper(ll) oxide with twice its volume of powdered charcoal. Place the mixture in a clean, dry Pyrex or Kimax test tube. Add about 10 ml of limewater to a second test tube, and stand it in a 150-mL beaker. Assemble the apparatus as shown here, with the copper-oxide test tube sloped slightly downward and the delivery tube extending into the limewater. 

Results of Fracture-Toughness Tests over the Range of Test Speeds. Figure 4 shows the stress intensity factor, KImax, versus test speed for all the materials tested. The test speed is the true opening displacement rate of the specimen when fracture occurs. It is measured by the optical device, and it can be up to 14 m/s. Typical times to fracture vary from 10 s at the lowest speeds to -150 xs at the highest. 

We observed exactly the same range of variation of KImax values in the 2L materials, and thus the same trend of fracture behavior, by lowering the temperature (11). The main difference was that the transition zones appeared more extended in speed than in temperature. Furthermore, the testing technique applied here permitted a better splitting of the contributions of initiation and propagation to the overall process of fracture than the Charpy testing described in reference 11. 

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