Search results for "slop"

Efficient pulsed 946-nm laser emission from Nd:YAG pumped by a titanium-doped sapphire laser

2008

Efficient pulsed room-temperature laser emission at 946 nm is obtained from a Nd:YAG rod pumped by a Ti-doped sapphire laser in the free-running mode. Three bonded YAG rods of 3-mm diameter with different Nd concentrations and active lengths were tested. A maximum output energy of 83.5 mJ at 3 Hz was obtained with a slope efficiency of 32.3% in an end-pumping configuration.

Emerging contaminants related to the occurrence of forest fires in the Spanish Mediterranean

2017

Forest fires can be a source of contamination because, among others, of the use of chemicals to their extinction (flame retardants, FRs), or by the production of Polycyclic Aromatic Hydrocarbons (PAHs) derived from high temperature alteration of organic matter. Up to our knowledge, this study is the first to assess the direct (PAHs 16 on the USA EPA's priority list), and indirect [tri- to hepta- brominated diphenyl ethers (PBDEs), organophosphorus flame retardants (PFRs) and perfluoroalkyl substances (PFASs)] contamination related to forest fires. The abundance and distribution of these contaminants were monitored on two Mediterranean hillslopes, one burned and one unburned, near Azuébar (S…

Real cover crops contribution to soil organic carbon sequestration in sloping vineyard

2019

Abstract The research focused on the evaluation of the effect of soil erosion processes on SOC sequestration rate after 5 years of cover crop soil management in Mediterranean vineyards (Sicily, Italy). Two paired sites, one in a sloping area and another one in a contiguous flat area, were chosen. The vineyard soils of the two plots of each paired site were managed with conventional soil tillage (CT) and Vicia faba cover crop (CC) the preceding 5 years. SOC was measured in three points along the slope (top, middle and foot parts) and in the flat area. Results showed that in the slope area the highest SOC content was found in CC management, with an average value of 9.52 ± 0.34 g kg−1, whereas…

Relationships between a new slope morphometric index and calanchi erosion in northern Sicily, Italy

2012

The Italian badlands, or “calanchi”, are common landforms in Mediterranean areas including central and southern Italy. Calanchi landforms may be compared to small hydrographic basins. These landforms are characterised by dense, hierarchical and rapidly evolving drainage systems carved into steep clayey slopes and by a sharply alternating pattern of furrows and narrow, generally sharp crests. This work presents a study of morphometric characteristics and a statistical analysis for two sites in northern Sicily (Italy), on outcrops of silty-clay deposits affected by active erosion processes, which give this area a typical calanchi landscape. In particular, factors closely linked to the charact…

Membrane bioreactors for treatment of saline wastewater contaminated by hydrocarbons (diesel fuel): An experimental pilot plant case study

2016

Abstract The paper reports the main results of an experimental campaign performed on a membrane bioreactor pilot plant designed to treat synthetic shipboard slops. The experimental campaign was divided into two phases: salinity acclimation up to 20 g NaCl L −1 (Phase I) and hydrocarbon (diesel fuel) dosing (Phase II). The observed results show that the carbon removal was not severely affected by the wastewater features. Conversely, respirometric tests showed that nitrification was strongly affected by the salinity (33% of nitrification efficiency at 20 g NaCl L −1 – Phase I) as a result of the salinity in the autotrophic biomass. Moreover, the sludge viscosity increased during Phase II due …

Designing Trickle Irrigation Systems in Sloping Fields without Pressure-Compensating Emitters: Application of the IRRILAB Software

2022

When designing trickle irrigation systems in sloped fields, the use of pressure-compensating (PC) emitters is generally preferred to ensure the emitter distribution uniformity regardless of the land topography and the variable operating pressures. However, the cost of PC emitters is generally higher than non-pressure-compensating (NPC) ones; moreover, the compensating membrane installed inside the emitters can lose elasticity due to the exposition to solar radiation, water quality, and chemical applications. Recently, the irrigation laboratory (IRRILAB) version 1.0 software application was developed to design microirrigation systems for rectangular and planar sectors when using NPC emitters…

A beam element allowing multiple slope discontinuities for RC structures: An application

2018

A beam/column element allowing the formation of multiple plastic hinges in columns or beams of a reinforced concrete (RC) framed structure is used in this work to show, through an application, its advantages with respect to conventional lumped plasticity models. Slope discontinuities can be located at any position of an Euler-Bernoulli beam span and not at the two extremes only. The model is in fact written in the framework of a modified lumped plasticity theory, and respectful of a thermodynamic approach. Flow rules and state equations are derived invoking the Theorem of maximum dissipation and using a Bresler's type activation domain. The beam element has already been implemented in a res…

Nonlinear Analysis of Reinforced Concrete Frames: Safety Evaluation and Retrofitting Techniques

Diode-pumped bulk Er:Yb:Glass 1.54μm pulsed laser with 1.2J output and 25% optical efficiency

2002

We report a pulsed transversely diode-pumped compact Er:Yb:Glass laser of uncomplicated design, delivering output energy of approx. 1.2J in free-running operation and 25% optical slope efficiency.

Design of Er3+-doped chalcogenide glass laser for MID-IR application

2009

Abstract The feasibility of a photonic crystal fiber laser (PCF laser), made of a novel Er 3+ -doped chalcogenide glass and operating at the wavelength λ s  = 4.5 μm is investigated. The design is performed on the basis of spectroscopic and optical parameters measured on a fabricated Er 3+ -doped Ga 5 Ge 20 Sb 10 S 65 chalcogenide bulk sample. The simulations have been performed by employing a home made numerical code that solves the multilevel rate equations and the power propagation equations via a Runge-Kutta iterative method. The numerical results indicate that a laser exhibiting slope efficiency close to the maximum theoretical one and a wide tunability in the wavelengths range where t…