The disposal of used tires is a major environmental problem throughout the world which causes environmental hazards. Crumb rubber is a waste material that is ideal for use in concrete applications. The aim of this study is achieved to use of rubber waste as partial replacement of fine aggregate to produce rubberize concrete in M30 mix. Different partial replacements of crumb rubber (0, 5, 10, 1...

Based on the classical regression model, timevarying coefficient model, unit root, co-integration, Granger causality test, VAR, impulse response and variance decomposition, the dynamic relationship between prices of natural rubber futures in China and Japan has been researched systematically. The following conclusions are gotten through empirical researches: Firstly, there is a stable co-integr...

We have measured the friction force acting on a rubber block slid on a concrete surface. We used both unfilled and filled (with carbon black) styrene butadiene (SB) rubber and have varied the temperature from -10 °C to 100 °C and the sliding velocity from 1 μm/s to 1000 μm/s. We find that the experimental data at different temperatures can be shifted into a smooth master-curve, using the temper...

Increasing demand for natural rubber prompts studies into the mechanisms governing the productivity of rubber tree (Heveabrasiliensis). It is very interesting to notice that a rubber tree of clone PR107 in Yunnan, China is reported to yield more than 20 times higher than the average rubber tree. This super-high-yielding (SHY) rubber tree (designated as SY107), produced 4.12 kg of latex (cytopla...

the amount and consistency of the applied forces to the tooth are important factors in tooth movements; therefore, the aim of this study was to compare the initial force and the force loss of three brands of elastics in 24 hours.in this in-vitro study sixty non-latex elastics (3/16 medium) from three companies (forestadent, dentaurum and ortho technology) were randomly selected. two static test...

Strong international demand for natural rubber is driving expansion of industrial-scale and smallholder monoculture plantations, with >2 million ha established during the last decade. Mainland Southeast Asia and Southwest China represent the epicenter of rapid rubber expansion; here we review impacts on forest ecosystems and biodiversity. We estimate that 4.3–8.5 million ha of additional rubber...

The plains of Sumatra and Kalimantan were sparsely populated at the turn of the 19th century (less than 4 inhabitants/km2), and the local population relied mainly on shifting cultivation of upland rice. The introduction of rubber by Dutch private Estates in the 1910's triggered a radical change in the landscape but no fundamental change in farming practices, at least at the beginning, with the ...

Most dentists are educated in rubber dam use in dental school, but there is often disparity between what is taught for various restorative procedures and what is practiced in the private sector. It is a common, although undocumented, belief that few practicing dentists routinely use rubber dam isolation. This study repeated a survey conducted in 1985 evaluating U.S. general dentists' attitudes ...

BACKGROUND This survey study aimed at investigating the frequency of rubber dam use during root canal treatment, identifying influencing factors for not using it by Saudi general dental practitioners (GDPs) and endodontists. It also aimed at identifying measures that increase rubber dam usage. METHODS After obtaining an ethical approval, two pilot studies were conducted on staff members at Ta...