Shear methods

Modulation contrast, like DIG, is a shearing method with the same advantages and disadvantages except that interference colors are absent with modulation contrast. The resolution, in spite of the restricted condenser aperture, is certainly not reduced. If anything, resolution seems to be improved and the images obtained have an excellent quaUty, especially in regard to contrast, one not seen with any other technique except the much more expensive video-enhanced imaging. 

Fig. 11. Effect of polyolefin primers on bond strength of ethyl cyanoacrylate to plastics. All assemblies tested in accordance with ASTM D 4501 (block shear method). ETFE = ethylene tetrafluoroethylene copolymer LDPE = low-density polyethylene PFA = polyper-fluoroalkoxycthylene PBT = polybutylene terephthalate, PMP = polymethylpentene PPS = polyphenylene sulfide PP = polypropylene PS = polystyrene PTFE = polytetrafluoroethylene PU = polyurethane. From ref. [73].

In block copolymer thin films, the perpendicular orientation of microdomains relative to the substrate cannot be achieved by the shear methods developed in the bulk case. Based on the additional variables (film thickness and surface/interface interactions) in block copolymer thin films, as described in Sect. 2.1.2, three different strategies are generally applied for orienting block copolymer thin films ... 

Tear measurement is covered by ISO 6383 [38] and compression stress strain by ISO 604 [39] but there are no ISO shear methods for plastics. 

ISO 1827 1991 Rubber, vulcanized or thermoplastic - Determination of modulus in shear or adhesion to rigid plates - Quadruple shear method ISO 1922 2001 Rigid cellular plastics - Determination of shear strength ISO 4587 2003 Adhesives - Determination of tensile lap-shear strength of rigid-to-rigid bonded assemblies... 

ISO 11003-1 2001 Adhesives - Determination of shear behaviour of structural adhesives -Part 1 Torsion test method using butt-bonded hollow cylinders ISO 11003-2 2001 Adhesives - Determination of shear behaviour of structural adhesives -Part 2 Tensile test method using thick adherents ISO 13445 2003 Adhesives - Determination of shear strength of adhesive bonds between rigid substrates by the block-shear method... 

ISO 15108 1998 Adhesives - Determination of strength of bonded joints using a bending-shear method... 

Fig. 2.1 Methods of estimating d, the projected area diameter (a) image shearing method [after Heywood (H6)] (b) statistical intercept method [after Martin et al. (Ml)].

Cohesive strength The consolidation of powder may result in arching and ratholing within transfer equipment. These behaviors are related to the cohesive strength of the powder, which is a function of the applied consolidation pressure. Cohesive strength of a powder can be measured accurately by a direct shear method. The most universally accepted method is described in ASTM standard D 6128-00 (3). 

ISO 1827, 1991. Determination of modulus in shear or adhesion to rigid plates -Quadruple shear method. 

Figure 5. Comparison of cure curves obtained by dynamic and by steady-shear methods.

Davis, S.S. Shotton, E. Warburton, B. Some limitations of continuous shear methods for the study of pharmaceutical semi-solids. J. Pharm. Pharmacol. 1968, 20, 157S-167S. 

Mechanical testing of the polyurethanes was performed by a modified identation/shear method described by Parsons and Black.(11) Relaxed and unrelaxed shear moduli of these polymers were measured in a simulated body fluid environment and compared to moduli of rabbit and human articular cartilage. This is shown in Table V. These tests, in addition to viscoelastic measurements of those polymers, indicate that this new polyurethane formulation is an excellent candidate for synthetic cartilage fabrication. 

BS 6319 Part 4 1984 Method for measurement of bond strength (slant shear method)... 

CNFs are intrinsically less conductive than either single-walled CNTs or multi-walled CNTs and CNF composites have the potential for creating inexpensive semiconducting polymers. These composites require a homogeneous dispersion within the polymer. Most well dispersed materials are made by high shear methods like twin screw extrusion [243,244]. However, the aspect ratios of the CNFs are significantly reduced, which leads to decreased mechanical properties and conductivity. 

BS 6319 Part 4 1984. Testing of resin compositions for use in construction. Part 4, Method for measurement of bond strength (slant shear method), British Standards Institution, London. 

Ultrasonication is another liquid-shear method of cell disruption. Ultrasonic vibrations having frequencies greater than 18 kHz are able to disrupt microbial cells in suspension. The ultrasonic vibration could be emitted continuously or in the form of short pulses. A frequency of 25 kHz is commonly used for cell disruption. The duration of this procedure depends on the cell type, the sample size and the cell concentration. The transmission of sonic waves creates a continuous cycle of microbubble cavitation in the suspending medium. These cavities or small bubbles of dissolved gases or... 

TEEEs can be processed successfully by low-shear methods such as laminating, rotational molding, and casting. Standard TEEElastomers are usually modified with viscosity enhancers for improved melt viscosity for blow molding. ... 

The constant shear method was used in the present work for the characterization of the emulsion phase because alkaline floods are carried out under analogous conditions of low but constant shear. Using the constant shear procedure, Schulman and Cockbain (16) measured the stability of O/W emulsions by observing the time required for the first visible signs of separation of the two phases. These authors concluded that this method is satisfactory to compare... 

The DPG was prepared by high speed shearing method at room temperature. 200 g of brine water and 200 g of bulk gel are added simultaneously to a colloid mill rotating at 3000 rpm and milled for 3 15 min at room temperature. The obtained solution from colloid miU were the final DPG products. 

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