some of arid regions problems of iran are saline and sodic soils. in improvement and reclamation of iranian arid rangelands, some foreign species of atriplex had been imported and adapted for many years ago. the most adapted species was atriplex canescens. at the present research, some environmental factors, vegetative characteristics (na, ca, mg and k), soil properties (moisture, ec, ph, solut...

in this study digital image correlation (dic) technique combined with a high speed video system was used to predict movement of particles in a water model. comparing with particle-image velocimetry (piv) technique, it provides a low cost alternative approach to visualize flow fields and was successfully employed to predict the movement of particles in a water model at different submergence dept...

We study surface-plasmon-enhanced terahertz transmission through subwavelength metallic hole arrays of sub-skin-depth thickness. Dynamic evolution of surface-plasmon resonance in terms of array thickness is characterized by use of terahertz time-domain spectroscopy in the frequency range 0.1-4.5 THz. A critical thickness of lead array film is observed, above which surface-plasmon coupling of te...

Abstract. This study develops the use of spectral total and diffuse irradiance measurements, made from a prototype hyperspectral total-diffuse sunshine pyranometer (SPN-S), to retrieve layer fine-mode aerosol (τaer) optical depths airborne platforms. Additionally, we analysis in an attempt partition depth into its τaer cirrus cloud (τcld) components absence coarse-mode aerosols. Two retrieval m...

This paper presents the first complete data of global downwelling irradiance (Ed) and the diffuse attenuation coefficient (K,,) for solar ultraviolet-B (UVB; 280 to 320 nm) in tropical waters. The penetration of solar UVB into shallow (0 to 5 m) seawater a t 3 sites in the central Indian Ocean and Andaman Sea, adjacent to areas of coral reefs. 1 t . d ~ studied using a semi-submersible scanning...

Damage to cotton by Rotylenchulus reniformis below plow depth was evaluated in a sandy clay loam soil at Weslaco, Texas. In December 1999, 14 holes on 51-cm centers were dug 91 cm deep along the planting bed and adjacent furrow and 2 ml of 1,3-dichloropropene was placed 91, 61, and 30 cm deep as each hole was refilled and packed. This technique eliminated 96%, 81%, and 74% of R. reniformis down...

Since nitrogen (N) is often limiting in permafrost soils, we investigated the N2-fixing genetic potential and the inferred taxa harboring those genes by sequencing nifH gene fragments in samples taken along a permafrost thaw gradient in an Alaskan boreal soil. Samples from minimally, moderately and extensively thawed sites were taken to a depth of 79 cm to encompass zones above and below the de...

X-ray absorption spectra can be collected in multiple ways, each exhibiting a different probing depth. The total electron yield signal contains contributions from primary, Auger and secondary electrons. We present data on the total electron yield probing depth at core level energies ranging from 77 to 929 eV. By coating materials with chromium overlayers, we find that the maximum probing depth ...

Background: Small photon fields are increasingly used in modern radiotherapy especially in intensity modulated radiation therapy (IMRT) and stereotactic radiosurgery (SRS) treatments. Accurate beam profile and central axis depth doses measurements of such beams are complicated due to the electron disequilibrium. Hence the EBT2 (external beam therapy) Gafchromic film was used for dosimetry of sm...