the principal effects of mass degradation on polymer matrix composites (pmcs) are the decay of mechanical properties such as strength, elongation, and resilience. this degradation is a common problem of the pmcs under thermal cycling conditions. in this article, composite degradation was investigated by measurement of total mass loss (tml) using the taguchi approach. thermal cycling tests were ...

soil is known as a suitable reservoir for carbon sequestration. the objective of this study was to investigate the capability of haloxylon on sequestration of carbon in sand dunes of yahya abad, sabzevar, in northeastern iran. eighty soil samples were taken from two depths of 0-5 and 5-10 cm under and between haloxylon trees. eight soil profiles under and between haloxylon trees were described ...

Land leveling is one of the most important steps in soil preparation and cultivation. Although land leveling with machines requires considerable amount of energy, it delivers a suitable surface slope with minimal soil deterioration as well as damage to plants and other organisms in the soil. Notwithstanding, in recent years researchers have tried to reduce fossil fuel consumption and its delete...

background. repairing aged composite resin is a challenging process. many surface treatment options have been proposed to this end. this study evaluated the effect of different surface treatments on the shear bond strength (sbs) of nanofilled composite resin repairs. methods. seventy-five cylindrical specimens of a filtek z350xt composite resin were fabricated and stored in 37°c distilled water...

abstract in this study the effects of land use changes from pasturelands to croplands on soil microbiological and biochemical properties were studied in kangaver, dehno and soltanye regions. composite soil samples from 0-20 and 20-40 cm depths of pasture and cultivated lands were taken from kangaver, dehno and soltanye regions, and soil microbial respiration, microbial biomass c and n, and urea...

in order to better understand the extent of soil pollution by heavy metals and its effect on ecosystem, spatial information on ecological impacts of heavy metals would be necessary. therefore, in the present study, the spatial pattern of ecological risk of heavy metals (cadmium, lead, copper, nickel and zinc) have been identified in surface soils of golestan province. to this end, over 346 surf...