Search results for " Yield"
showing 10 items of 550 documents
Modelling sediment delivery processes by a stream tube approach
1999
Abstract The sediment delivery processes due to the travel along a hydraulic path having an uniform slope and to the concave shape of the path are modelled. In particular, using a power equation for modelling the slope profile and RUSLE with two different expressions of the topographic factors, a criterion to define the erosion active slope length, i.e. the slope length in which no deposition processes occur, is initially proposed. Then, the RUSLE equation is adapted to concave profiles by a correction factor of the topographic factors depending on slope curvature. Finally, the deduced relationships (equations (19) and (27)) for correcting the topographic factors for a concave slope are exp…
Conventional tillage versus no-tillage: Nitrogen use efficiency component analysis of contrasting durum wheat genotypes grown in a Mediterranean envi…
2023
Very little information is available for Mediterranean areas about the soil N dynamics and crop N use efficiency during the transition phase from conventional tillage (CT) to no-tillage (NT). Hence, a 2-yr experiment was conducted under semiarid Mediterranean conditions in three sites to study how soil N dynamics, crop N uptake, grain yield, and N use efficiency vary with N-fertilization rate and crop genotype in the switch year from CT to NT. Treatments consisted of two tillage systems (CT and NT), five N-fertilization rates (0, 40, 80, 120, and 160 kg N ha−1), and two durum wheat (Triticum durum Desf.) genotypes (one modern variety and one old landrace). Irrespective of the genotype, NT r…
Environmental, Agricultural, and Socioeconomic Impacts of Salinization to Family-Based Irrigated Agriculture in the Brazilian Semiarid Region
2020
Soil salinity is one of the major abiotic factors causing a serious threat to global food security, mainly in arid and semiarid regions. Salinity brings socioeconomic impacts associated with low crop productivity and devaluation of agricultural lands. In this chapter, we approach agricultural, environmental, and socioeconomic impacts of soil salinization. We also report two case studies from irrigated areas of the Brazilian semiarid, where previously cultivated lands were abandoned due to increased soil salinity. A survey of the published literature showed that soil salinity became a global problem that is accelerated by human activities such as deforestation and lack of irrigation manageme…
Economic values for production and functional traits in Valle del Belice dairy sheep using profit functions
2011
Abstract A deterministic static model was used to estimate the economic values (EV) of production (MY, milk yield; BW, birth weight; and ADG, average daily gain) and functional traits (ASR, adult survival rate; LSR, lamb survival rate; FE, fertility; PR, prolificacy; and LW ewe , mature weight of ewe) in Valle del Belice dairy sheep. In this study, values for the biological parameters and the production traits used in the model were taken from real data, by surveying 15 Valle del Belice farmers and reflected the production circumstances of pasture based dairy production systems. In this system feed cost accounted for 95% of total variable costs, whereas fixed costs were low and reflected tr…
Ag44(EBT)26(TPP)4Nanoclusters With Tailored Molecular and Electronic Structure
2021
Although atomically precise metalloid nanoclusters (NCs) of identical size with distinctly different molecular structures are highly desirable to understand the structural effects on the optical and photophysical properties, their synthesis remains highly challenging. Herein, we employed phosphine and thiol capping ligands featuring appropriate steric effects and synthesized a charge-neutral Ag NC with the formula Ag44 (EBT)26 (TPP)4 (EBT: 2-ethylbenzenethiolate; TPP: triphenylphosphine). The single-crystal X-ray structure reveals that this NC has a hollow metal core of Ag12 @Ag20 and a metal-ligand shell of Ag12 (EBT)26 (TPP)4 . The presence of mixed ligands and long V-shaped metal-ligand …
Impact of the use of sterically congested Ir(III) complexes on the performance of light-emitting electrochemical cells
2018
International audience; The synthesis, structural and optoelectronic characterization of a family of sterically congested cyclometalated cationic Ir(iii) complexes of the form [Ir(C^N)2(dtBubpy)]PF6 (with dtBubpy = 4,4′-di-tert-butyl-2,2′-bipyridine and C^N = a cyclometalating ligand decorated at the 4-position of the pyridine ring and/or the 3-position of the phenyl ring with a range of sterically bulky substituents) are reported. This family of complexes is compared to the unsubstituted analogue complex R1 bearing 2-phenylpyridinato as cyclometalating ligand. The impact of sterically bulky substituents on the C^N ligands on both the solid state photophysics and light-emitting electrochemi…
Deficit irrigation does not affect alternate bearing of ‘Valencia’ orange trees
2018
This study evaluated the effect of long-term partial rootzone drying and continuous deficit irrigation on the degree of alternate bearing of adult ‘Valencia’ orange trees grown in northern Sicily. Three irrigation strategies were imposed in summer from 2007 to 2011: irrigation with volumes corresponding to 100% of crop evapotranspiration applied to entire rootzone (CI), partial rootzone drying (PRD) with 50% of CI water applied to one alternated side of the rootzone, and continuous deficit irrigation (CDI) with 50% of CI water applied to both sides of the rootzone. The experiment was conducted on 48 adult orange trees arranged according to a randomized block design. Weather and soil paramet…
Regioisomerism in cationic sulfonyl-substituted [Ir(C^N)2(N^N)]+ complexes: its influence on photophysical properties and LEC performance
2016
A series of regioisomeric cationic iridium complexes of the type [Ir(C^N)2(bpy)][PF6] (bpy = 2,2'-bipyridine) is reported. The complexes contain 2-phenylpyridine-based cyclometallating ligands with a methylsulfonyl group in either the 3-, 4- or 5-position of the phenyl ring. All the complexes have been fully characterized, including their crystal structures. In acetonitrile solution, all the compounds are green emitters with emission maxima between 493 and 517 nm. Whereas substitution meta to the Ir-C bond leads to vibrationally structured emission profiles and photoluminescence quantum yields of 74 and 77%, placing a sulfone substituent in a para position results in a broad, featureless em…
Assessment of soil particle erodibility and sediment trapping using check dams in small semi-arid catchments
2017
Check dams can be used as a source of information for studies on sediment characteristics and soil particle erodibility. In this study, sediment yield and grain size distribution (GSD) were measured in twenty small catchments draining into a rock check dam in NW Iran for different runoffs during 2010–2011. Significant correlations were found between sediment yield and slope steepness, vegetation cover and soil erodibility factor (K) of the catchments. The erodibility of soil particles was determined using the comparison of GSD between sediment and original soil. Clay was the most erodible soil particle which showed 2.05 times more percentage in sediment than the original soil. The erodibili…
Effect of donor substituents on thermally activated delayed fluorescence of diphenylsulfone derivatives
2019
This research was funded by the European Social Fund according to the activity ‘Improvement of researchers’ qualification by implementing world-class R&D projects’ of Measure No. 09.3.3-LMT-K-712. DG acknowledges to the ERDF PostDoc project No. 1.1.1.2/VIAA/1/16/177;