Strip sampling

In this test, a rectangular strip sample is formed around a die with a precisely machined edge of a known radius. The sample is formed by 90° or 180° about an axis in the plane of the sheet. The outer surface of the bend is inspected for cracking or unacceptably deep surface mmpling for the particular appHcation. The minimum bending radius (MBR) about which strip can be successfully formed depends on the strip thickness, t, and is reported with the test thickness specified or normali2ed with regard to thickness as MBR/1. Better formabiHty is indicated by smaller MBR/1 values. 

Tensile tests were carried out on recombinant resilin in PBS buffer on an Instron Tensile Tester (model 4500) at a rate of 5 mm/min and a temperature of 21°C. The swollen strip samples (7 X 1 mm) had a gauge length of 5 mm and were cycled initially up to a strain of about 200%. The... 

Water Collect water sample acidify strip sample with helium collect gas in nitrogen-cooled trap. GC/FPD 0.6 imol/g NR Radford-Knoery and Cutter 1993... 

Water Strip sample in sparger with helinm adsorb efflnent gas to adsorption tnbe thermally desorb to GC GC/FID/MS 10 g/L 89.7-95.7 Bianchi et al. 1991... 

An empirical, but often practical way of sampling has been presented by EXNER et al. [1985]. They divided an area into suitable clean-up units of practical size to solve a problem of hazardous waste. Inside these strips, samples were taken along transects and some composite samples were formed from different combinations of the individual samples. After homogenization of the composite samples randomly selected aliquots of soil were taken and analyzed. The estimated arithmetic mean and its standard deviation enabled computation of an upper confidence limit for the mean concentration of the clean-up units. 

A practical method for the investigation of two-dimensional contamination, which includes the use of grid plans and easy-to-handle composite samples, is described in the literature [ASSMUS et al., 1985] under the name strip sampling. 

Fig. 4-8 illustrates an example of strip sampling for determination of lead pollution in an agricultural area [KRIEG,1995],... 

FIGURE 17.13 Effect of topically applied Optimase on desquamation in vivo. Soap-induced dry skin was treated with Optimase (12 GU/ml) and moisturizer for three days. Tape strip samples of SC were taken and dsc 1 levels were quantified. From El-Kadi, K., Rawlings, A.V., Feinberg, C., Nunn, C., Battaglia, A., Chandar, P., Richardson, N., Sabin, R., and Pocalyko, D. Arch. Dermatol. Res., 293, 500-507, 2001. 

Culturing of Test and Control Samples. Both control and treated spore strip samples were cultured at 37 °C in trypticase soy broth for 48 hr to determine kill. Swab samples, taken from sections of the surface of the muddy-moldy pages before and after exposure to ethylene oxide, were placed in 1 mL of 0.001M phosphate buffered saline solution at pH 7.0 for plating on appropriate media. These samples were taken from a 6.45-cm2 section. 

Epoxy film samples were prepared with the DGEBA-TETA and N-5208 resins. Detailed Information on the DGEBA-TETA and N-5208 resin cure and sample preparation has been previously provided (2,4). Films of the N-5208 resin were made with a curing agent concentration of 25 PHR-DDS (4) 14 PHR TETA was used for curing the DGEBA epoxy (2). Dynamic mechanical properties for films were measured on strip samples cut to nominal 0.02 cm x 0.3 cm x 6.0 cm dimensions. 

Subtract the mass of the stripped sample from the original mass and record in your notebook. This is the mass of the zinc that was on the sample. 

Ascending development. Cut three strips of No. 1 paper 24 cm long. Apply 10 pi of the solution containing about 2.5 pg of each metal to the centre of the strip about 2 cm from one end. Place the solvent in the gas jars to a depth of 3 cm and roll the jars round to wet the walls with solvent. Suspend the paper strips, sample spots to the bottom, in the sealed gas jars just clear of the solvent. Allow to stand for a few minutes, to equilibrate the liquid and... 

Mattorano, D.A., Kupper, L.L., and Nylander-French, L.A., 2004, Estimating dermal exposure to jet fuel (naphthalene) using adhesive tape strip samples, Ann. Occup. Hyg., 48, 139-146. 

AI2O3. Aluminum (A1 99.99) thin strip samples (1 mm in thickness) were electrolytically polished in phosphoric acid/ sulfuric acid electrolyte and anc ized in sulfuric acid electrolyte (200 g/L H2SO4, 20 °C, 4 min), producing an anodic oxide layer of about 2 fim thickness (Alusuisse, Neuhausen am Rheinfall, Switzerland). 

In the in vivo human skin model, a hand is generally placed in the solution under study or a predetermined skin area from the back or forearm is treated for a specified time, after which the material of interest remaining on the skin is removed. Absorption is measured by assessing changes in plasma or urine concentration over time or from stratum comeum concentrations in tape stripping samples [82, 92]. Other methods of detection have been employed and will be discnssed. 

The author also investigated the comparative effects of physical and chemical monomer reduction (stripping) on chloromethyl and methyl isothiazolinones in a polyvinyl acetate/butyl acrylate co-polymer dispersion in a large scale plant trial. Results are detailed in Table 16 and show that even under apparently strongly oxidising conditions CIT was degraded by up to 75% when redox monomer reduction was used. In comparison no such effect was seen with the physically stripped samples. 

Cross-head movement or grip separation is sometimes taken as a measure of sample extension. This is clearly only true of a parallel strip sample having the same cross-section throughout its length. Such samples inevitably break in the grips area due to the pressure imposed by the grips [11]. For some time these were the only methods available to most testers and they did enable comparisons of materials to be made, if in a somewhat coarser manner than possible today. 

Static heat stability measurement has been automated with a device called the Metrastat (supplied by Dr Stapler GmbH of Dusseldorf). In this equipment, several strip samples move at an adjustable rate into and through an oven at preset temperature. After exposure, the strip can be checked for discoloration versus time of exposure, stored as the entire strip, or cut into sections for mounting (as with individual specimens from an oven). This enables other laboratory operations to be mn simultaneously without the hazard of omitting to take samples from the oven inadvertently. Auxiliary equipment is available from the supplier to monitor hydrogen chloride evolution and to check for development of fluorescence in the sample (from formation of conjugated unsaturation, typically a precursor to appearance of visible discoloration). This versatility makes the Metrastat an excellent compound development tool. Determination of fluorescence is the subject of ASTM E 1247. 

The centrifugal sampler has a rotating paddle wheel, open to the environment on one end, with a stationary removable agar-coated plastic strip around the rim of the wheel. Air enters along the axis, and the particles contained in it are driven by centrifugal force onto the collecting strip. Sample flow rates are 40 to 50 L/min. 

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