59 research outputs found
Evaluating land use and management Natural Flood Management potential
Soil use and management as a form of Natural Flood Management (NFM) has potential to increase infiltration and soil water storage above and below ground. As a result, it can slow the flow of water and reduce flooding caused by surface run-off, rivers and groundwater. Here, we report findings from the LANDWISE project, which examined the potential of land use and management in lowland groundwater-fed catchments in the River Thames Basin, England. We focused on five soil classes within two geology types: shallow permeable soils on carbonate geology (Limestone and Chalk) and deep clay soils on mudstone geology; across agricultural land, grassland and woodland. We compared different farming systems, including conventional, innovative and organic agriculture. We gathered empirical evidence of within and between field variation for different soil use and management strategies, through a broad survey of 164 fields and an in-depth survey of 7 sites. We show that both land use and soil type are significant in affecting bulk density. We also show correlation between organic matter and bulk density, which is important for NFM as organic matter content can be controlled by land use and management practices. We adopted a co-production research approach, to deliver usable impacts for farmers who will ultimately deliver NFM through land use change and management. This work will inform policy and design and delivery of agri-environment schemes; such as the soil survey scheme, a key part of the DEFRA soil action plan. It will help co-deliver NFM alongside other ecosystem services
Flavor Decomposition of the Polarized Quark Distributions in the Nucleon from Inclusive and Semi-inclusive Deep-inelastic Scattering
Spin asymmetries of semi-inclusive cross sections for the production of
positively and negatively charged hadrons have been measured in deep-inelastic
scattering of polarized positrons on polarized hydrogen and 3He targets, in the
kinematic range 0.023<x<0.6 and 1 GeV^2<Q^2<10 GeV^2. Polarized quark
distributions are extracted as a function of x for up $(u+u_bar) and down
(d+d_bar) flavors. The up quark polarization is positive and the down quark
polarization is negative in the measured range. The polarization of the sea is
compatible with zero. The first moments of the polarized quark distributions
are presented. The isospin non-singlet combination Delta_q_3 is consistent with
the prediction based on the Bjorken sum rule. The moments of the polarized
quark distributions are compared to predictions based on SU(3)_f flavor
symmetry and to a prediction from lattice QCD.Comment: 14 pages, 6 figures (eps format), 10 tables in Latex New version
contains tables of asymmetries and correlation matri
Aluminum-rich belite sulfoaluminate cements: clinkering and early age hydration
Belite sulfoaluminate (BSA) cements have been proposed as environmentally friendly building
materials, as their production may release up to 35% less CO2 into the atmosphere when compared
to ordinary Portland cements. Here, we discuss the laboratory production of three aluminum-rich
BSA clinkers with nominal mineralogical compositions in the range C2S (50-60%), C4A3, i.e. a value as close as possible to the nominal composition. Under these experimental conditions, three different BSA clinkers, nominally with 20, 30 and 30 wt% of C4A3 respectively, as determined by Rietveld analysis. We also studied the complex hydration process of BSA cements prepared by mixing BSA clinkers and gypsum. We present a methodology to establish the phase assemblage evolution of BSA cement pastes with time, including amorphous phases and free water. The methodology is based on Rietveld quantitative phase analysis of synchrotron and laboratory X-ray powder diffraction data coupled with chemical constraints. A parallel calorimetric study is also reported. It is shown that the b-C2S phase is more reactive in aluminum-rich BSA cements than in standard belite cements. On the other hand, C4A3$ reacts faster than the belite phases. The gypsum ratio in the cement is also shown to be an important factor in the phase evolution
Erratum to: "Nuclear Effects on R=\sigma_L/\sigma_T in Deep-Inelastic Scattering" Phys.Lett. B475(2000)386
This erratum revokes the main conclusion of a Letter that reported
measurements of cross sections for deep-inelastic scattering (DIS) of leptons
on He and N targets, expressed as ratios of to
the cross section on the deuterium target.Comment: 3 pages, 1 figur
- …