Joint tests

A sealant s adhesion is commonly studied by 180 degree peel tests such as ASTM C794 or by tensHe/adhesion joints tests such as ASTM C719. The adhesion test protocol should simulate actual field conditions as closely as possible. Sealants often have good adhesion to dry substrates, but this adhesion may be quickly destroyed by water. Because most sealants are exposed to water over their lifetime, adhesion testing should include exposure to water for some length of time. ASTM C719 is one of the better tests to determine a sealant s adhesion durabHity as it exposes sealants to seven days of water immersion. 

An early study by Rudkin (1950) showed that substitution of OH groups with acetyl resulted in a significant decrease in bond strength between the wood and a UF resin in lap-joint tests. Vick and Rowell (1990) studied the adhesive bonding of acetylated yellow poplar, with 18 different thermoplastic and thermosetting adhesives. The effectiveness of the adhesives was examined by determination of bond shear strength (and wood failure) of 6 mm thick, bonded wood strips after conditioning at 27 °C and... 

ISO 13783 1997 Plastics piping systems - Unplasticized poly(vinyl chloride) (PVC-U) end-load-bearing double-socket joints - Test method for leaktightness and strength while subjected to bending and internal pressure... 

Siloxane-containing devices have also been used as contact lenses, tracheostomy vents, tracheal stents, antireflux cuffs, extracorporeal dialysis, ureteral stents, tibial cups, synovial fluids, toe joints, testes penile prosthesis, gluteal pads, hip implants, pacemakers, intra-aortic balloon pumps, heart valves, eustachian tubes, wrist joints, ear frames, finger joints, and in the construction of brain membranes. Almost all the siloxane polymers are based on various polydimethylsiloxanes. 

WALD procedure. Estimates and standard errors I for nonlinear functions and joint test of I... 

Dillard D A, Leichti K M, Lefebvre D R, Lin C, Thornton J S. Adhesively Bonded Joints, Testing, Analysis and Design, Baltimore, 1986, Proceedings p 83. 

There are several ways that actual joints can be tested. For quality control purposes, a proof test is commonly used, as described above. This test imposes a stress on the specimen but limits it to a point well below where any destruction of the joint can occur. This type of test only looks for serious flaws in the bonding processes such as interface contamination, air entrapment in the joint, or undercured adhesive. The prototype joints can also be tested to destruction by using similar test methods described above for standardized testing. This, however, is generally not done at great frequency because of the cost. Generally, most actual joint tests are performed to ascertain the cause of failure (i.e., forensic analysis of the failed joint) or for nondestructive determination of the adequacy of the bond. 

Anderson, G. P., et al., Effect of Removing Eccentricity from Button Tensile Adhesive Tests, Adhesively Bonded Joints Testing, Analysis, and Design, ASTM STP 981, W. S. Johnson, ed., American Society of Testing and Materials, Conshohocken, PA, 1988. 

In many cases there will be a certain demand for protective coatings (paints) against corrosion for the joint surfaces. This question should be handled very carefully. Many coatings contain particles (e.g. aluminium) which may adversely affect the flameproof properties of the joint. Tests should be made to ensure the coating s appropriateness for this application. 

At the time the end-joint test unit was being built, the industry used both horizontal and vertical end-joint profiles. This question/dilemma was eliminated by designing the unit for a lumber cross-section of 1.5 x 1.5 inches. Restriction to this dimension was also necessary to keep the power requirements within reasonable limits. At present, the unit is limited to approximately 3,000 psi in tension, at which point the hydraulically-driven grips begin to slip. The unit thus allows one to determine the strength development in the joint during the... 

This work was funded by the USDA Small Business Innovation Research Grant No. 86-SBIR-8-0126. The authors thank Mr. Gary Smith for his assistance in testing specimens. Weyerhaeuser Company kindly made the end-joint test unit and provide laboratory space available. The Borden Chemical Company provided the PRF resin LT-75 and the hardener FM-260. The Chembond Company provided the resin RF-900. Boise Cascade Corporation kindly provided southern pine bark from its plywood plant at Oakdale, Louisiana. 

Preliminary emf measurements were made on Cell I, and the standard potential of the Ag-AgBr electrode was determined as 0.07106 V from data taken in 0.01000 mol kg"1 hydrobromic acid. This value of Em° was identical with that given in the literature (20). The emf values were reproducible up to m = 1.0 mol kg"1. There was some evidence of irreversible behavior for m = 1.5 mol kg"1. In order to avoid this kind of drift in the emf values at the highest constant total molality tested, the cell with the hydrogen electrode was allowed to equilibrate for 45 min before the Ag-AgBr electrode (which was kept in a separate standard-joint test tube containing a solution of the same composition) was transferred to the electrode compartment. The equilibrium emf value was recorded every 5 min until no deviation was noticed. 

Risdon, T.J. and Sargent, D.J., Comparison of Commercially Available Greases With and Without Molybdenum Disulfide Part II - Oxidation Stability and Ball Joint Tests, NLGI Spokesman, 34, 358, (1971). 

Table 1, Comparison of Gjc and Gnc values at initiation and for propagation in test joints tested.

A Modified Method of the Rice Lamina Joint Test for Brassinosteroids... 

We are able to readily search for naturally occurring brassinosteroid using rice-lamina joint test [LJT] (1) as the bioassay method and GC/MS as the microanalytical method, which was established by Ikekawa and his co-workers as a microanalytical method for BS (2). Plant material was extracted three times in methanol or 80% methanol-H20. After the extract was evaporated under reduced pressure, the resulting aqueous residue was extracted with EtOAc at pH3 and the EtOAc fraction was partitioned with Na2C03-NaHC03 buffer at pH 10 to get neutral substances. 

In any case, both the FEA/ERR analysis from this study and the experimental results cited from the literature clearly demonstrate the importance of considering adherend thickness in the design of Joints. Test results and commonly used design rules that ignore this aspect of adhesive joints should be used with great caution. 

DeVries. K. L. and Borgmeier. P. R- Interpreting Adhesive Joint Tests. 2 International Congress on Adhesion Science and Technolog, Ed. K.L. Mittal. 135. VSP. NL. 2002. [lljKinloch. A. J., Adhesion and Adhesives Science and Technology. Chapman and Hall. New York, 1987. 

The statistie for the joint test is = f[Gs (X X) G ]" f =. 5789. This is less than the eritieal value for a ehi-squared with two degrees of fr eedom, so we would not rejeet the joint hypothesis. For the individual hypotheses, we need only eompute the equivalent of a t ratio for eaeh element of f. Thus,... 

Get the drug to the site of infection The brain, joints, testes, and eye are "protected" sites in the body. Few drugs penetrate the barriers that surround these sites. When treating infections at these sites, one must choose agents that penetrate the barriers and that are active against the infecting organism. Similarly, abscess walls form an effective barrier to antibiotics. Abscesses must be incised and drained. 

The derived wear factor (k) for the Freeman-Swansog and Leeds knee joints tested in the simulator for about 10 cycles are both interesting and similar. The ln-vlvo Freeman-Swanson joint was kindly made available by Professor S.A.V. Swanson and the conditions of service were not known with any certainty. The joint had functioned in an elderly patient for some four years, with a light to medium level of walking activity. It was therefore assumed that /PdX remained constant at 47.7 Nm/cycle and that the patient achieved 6000 strides or 3000 loading cycles per day. These assumptions are consistent with a subsequent study of the walking activity of patients fitted with total replacement joints reported by Wallbrldge and Dowson, but considerable scope for errors... 

At the same time, the Institute for Materials Seienee Problems of NAS of Ukraine (IMSP) has made an oxide zireonium-based fuel eell. By agreement between IPMash and IMSP, joint tests of the equipment developed will be eondueted to reeeive souree data for designing the experimental complex "Mine-TPP" (ECMT) with a capaeity of 6 MW. 

Verbruggen, G. and Veyes, E.M. Degenerative joints test tubes, tissues, models, and man. Proc. First Conference on Degenerative Joint Diseases, Excerpta Medica, Amsterdam-Oxford-Princeton, 1982. 

Adhesively Bonded Joints Testing, Analysis, and Design, STP 981, edited by W.S. Johnson, 1988, 320 pp., ASTM International. 

Figure 4 Standard lap shear geometries (a) simple lap joint test, ASTM D-1002 (b) laminated lap shear joint test, ASTM D-3165 (c) double lap joint test, ASTM D-3528.

Three tests to failure on the C1 C1 C1 joint configuration were carried out in [41]. The study found that one joint failed in net-tension at hole 1 in the lower laminate at a joint load of 80 kN, while another failed by net-tension at hole 3 in the top laminate at 84 kN. The third joint tested failed by bolt failure at 76 kN. It should be noted that bearing damage was evident at holes where bolt failure occurred. However, as this damage mode is non-catastrophic, high loads are transferred through the bolt until... 

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