coeffcient of  friction  (cof)  for  rubber parts  is one of  the key parameters in their interaction with solid rough surfaces (micrometer to millimeter scales),  such  as  tire-road  interactions. cof  of  rubber  depends  on  viscoelastic properties of rubber, roughness characteristics of the counter-part surface, and process variables such as contact nominal pressure and sliding speed. due ...

A comparative study on biodegradation of di-cumyl peroxide (DCP) crosslinked and uncrosslinked natural rubber by Pseudomonas sp. was carried out. Decrease in organic carbon content along with the changes in tensile strength of the treated rubber, both DCP crosslinked and uncrosslinked natural rubber, indicated rubber hydrocarbon utilization by the Pseudomonas sp. A decrease in 60.88% MPa and 41...

since reusing waste tire as a cheap filler is considerably high, in this study, recycled rubber to replace nr/br is used up to 15 phr and the positive and negative aspects of the rubber powder and reclaimed rubber in the physical, dynamical and processing properties are evaluated. the results showed that in the presence of recycled rubber, the cure rate, crack growth resistance, tear strength a...

Natural rubber (NR) latex collected from the Hevea trees exists as a colloidal suspension (Verhaar, 1959). The amount of latex obtained on each tapping is about 300 mL. The tapping is usually done once every 2–3 days for 9 months each year. Usually, the collected latex is treated with formic acid to coagulate the suspended rubber particles within the latex (Gazeley et al., 1988). After having b...

The aim of this study was to compare the isolation systems OptraDam® Plus and OptiDam™ with the conventional rubber dam in terms of objective and subjective parameters. The isolation systems were applied during the dental treatment of the patients. The time of preparation, placement, presence and removal were measured and the quality of isolation was evaluated. The median time of rubber dam pla...

Optimum conditions for the rapid, efficient, nondestructive determination of rubber producing potential in guayule (Parthenium argentatum) were established. The rubber producing potential may be defined as the ability of the plant material to synthesize rubber from a precursor under specified conditions. To achieve this, stem slices taken from the first 5 centimeters of branches were incubated ...

Natural rubber was extracted from the fig tree (Ficus carica) cultivated in Korea as part of a survey of rubber producing plants. Fourier transform infrared and (13)C nuclear magnetic resonance analysis of samples prepared by successive extraction with acetone and benzene confirmed that the benzene-soluble residues are natural rubber, cis-1,4-polyisoprene. The rubber content in the latex of fig...

Over the course of development, the vertebrate heart undergoes a series of complex morphogenetic processes that transforms it from a simple myocardial epithelium to the complex 3D structure required for its function. One of these processes leads to the formation of trabeculae to optimize the internal structure of the ventricle for efficient conduction and contraction. Despite the important role...

Activation of mast cells by aggregation of the high-affinity IgE receptors (FcεRI) initiates signaling events leading to the release of inflammatory and allergic mediators stored in cytoplasmic granules. A key role in this process play changes in concentrations of intracellular Ca(2+) controlled by store-operated Ca(2+) entry (SOCE). Although microtubules are also involved in the process leadin...

a newly developed natural rubber deproteinization process produces deproteinized natural rubber (dpnr) wastewater as an intermediate product containing a high concentration of sodium dodecyl sulfate (sds) and rubber. in this study, a novel process to recover the residual rubber and energy as methane from dpnr wastewater was developed. as a pretreatment, sds and residual rubber in dpnr wastewate...