this work investigates the effect of the application rate and type of sludge throughout the soilcarbon cycle in a semiarid mediterranean agro-ecosystem. we study the two-year evolution of the variouspools of soil organic and inorganic carbon and their influence on soil respiration. we applied three rates (40, 80 and 160 mg/ha) of two types of sludge –aerobically and anaerobically digested sewag...

Adsorption is a chemical method for water purification. In the present study, native and impregnated active carbon was used for adsorption to evaluate the efficacy of the process in manganese removal from aqueous solutions. Impregnation reaction was performed using the precipitate colloids of manganese oxides onto the carbon surface. X-ray diffraction, Fourier-transform infrared spectroscopy, a...

this paper investigates axial compression process of multi-layered tubes with circular cross-section under the axial loading in the quasi-static condition using experimental method. some specimens are prepared in seven different groups, namely; empty carbon/epoxy composite tubes, solid carbon/epoxy composite rods, empty copper tubes, composite tubes with silicon sealant filler, concentrically s...

climate change due to increasing the level of greenhouse gases including co2 is the main environmental issue of the world in the new century. one of the effective way for reducing atmospheric co2 is carbon sequestration by plants and soils. a vast area of iran has desert condition with special adapted plant species in which can be devoted for carbon sequestration. hammada salicornica as a shrub...

There is no single standard technique or methodology to characterize the size, structure, number, and chemical composition of airborne carbon nanotubes.  Existing analytical instruments and analytical techniques for evaluating nanoparticle concentrations cannot simultaneously provide morphology, state of agglomeration, surface area, mass, size distribution and chemical composition data critical...

Torsional dynamic analysis of carbon nanotubes under the effect of longitudinal magnetic field is carried out in the present study. Torque effect of an axial magnetic field on a carbon nanotube has been defined using Maxwell’s relation. Nonlocal governing equation and boundary conditions for carbon nanotubes are obtained by using Hamilton’s minimum energy principle. Eringen’s nonlocal stress gr...

We evaluated the effect of Fe/Alumina Catalyst contained different Cadmium contents and two synthesis temperatures on producing carbon nanotubes by chemical vapor deposition of methane as a feedstock.  X-ray powder diffraction (XRD), N2 adsorption-desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy and Thermogravimetry analysis (TGA) were u...

in a semiarid region of central iran, effects of parent materials, physiography and landscape position, land use, andmanagement practices on association of organic carbon with secondary (aggregates) particles and aggregate stability canhave important consequences in terms of carbon sequestration and budgeting, deciding on the proper land use strategy andsuitable soil conservation practices. it ...