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...

in the construction process of a plastic concrete cut-off wall, concreting is usually performed using the termie pipe method. in this method, concreting is performed from the lowest point in the excavated trench (containing the slurry) using a funnel and the pipe connected to it. the concrete poured in the funnel gradually settles in the panel through the termie pipe which is beneath the slurry...

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...

Open boundary conditions. Since the source current, Eq. 1, extends from z = −∞ to +∞ whereas our computational domain is finite, one has to apply suitable boundary conditions (see also [2]). Consider some accelerator component, residing in a vacuum cavity with attached beam pipe of smaller cross section than the cavity. Generally, the transitions from the pipe to the module have to be included ...

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...

BACKGROUND Previous studies investigating the effect of cigar or pipe smoking on the occurrence of chronic cough and chronic phlegm have reported prevalences among cigar and pipe smokers lying between those of non-smokers and current cigarette smokers. This study uses data on previous cigarette consumption, current cigar or pipe consumption, and biochemical markers of smoking to provide a detai...

An automated algorithm based on the dynamic hydrological and hydraulic simulation modules in Storm Water Management Model (SWMM) was developed to aid the design of storm sewer networks, provided that a layout is given. Numerical performance of the proposed algorithm was compared with the existing design methods with two application cases. The automated computation process of the sewer network d...

the experiment was to study the effects of replacing soybean meal by rubber seed meal on growth, economics and carcass characteristics of broiler. a total of 150 day-old commercial broiler (cobb-500) was reared for a period of 35 days. there were five treatments including t0 (without rubber seed meal), t1 (10% rubber seed meal), t2 (20% rubber seed meal), and t3 (30% rubber seed meal) and t4 (4...