Experimental abatement data of underflow baffles for removal of floatables in the CSOs of the Greater Montréal (Canada) area.

Underflow baffles have gained in popularity over the years as a viable mean to intercept floatables in Combined Sewer Overflows (CSOs). This choice was mainly justified by the extremely low capital cost (CAPEX) and operational cost (OPEX) of this solution, although the efficiency of underflow baffles has never been clearly proven. The only similar application to underflow baffles are scum boards in grit chambers and clarifier. However, the flow conditions at CSOs vary considerably from those in grit chambers and clarifier. For this reason, review of the behavior of floatables in a rapid flow is paramount. Only then can comprehensive design criteria for underflow baffles and overflow chambers be suggested. Pilot scale tests, performed in a 17 metres long basin at various flowrates, had already shown that a critical horizontal velocity for floatables (Vcr) may develop in the overflow chambers. In this follow up study, the fate of intercepted floatables was investigated. It appears from this latest data that permanent capture of floatables decreases rapidly with an increase in the horizontal velocity of the flow, no matter what the baffle depth. Baffle depth increases capture at lower velocities (0.17 m/s) but become irrelevant at higher velocities (0.61 m/s). This data suggests that capture efficiency of existing underflow baffles in overflow chambers can be, at best, very low whenever the horizontal velocity increases above 0.30 m/s or 1 ft/s.     

Physical parameters of fiber affecting passage from the rumen

Our objective was to review the factors that affect fiber passage from the rumen. Rumen residence time and passage from the rumen are important in control of intake, digestibility, protein metabolism, and protein escape. Physical factors associated with particle size and particle specific gravity affect passage from the rumen. Although particles of 5 cm may pass through the reticulo-omasal orifice, most particles leaving the rumen are smaller than 1 mm. Polypropylene ribbon cut into 7-cm lengths, introduced into the rumen, markedly reduced intake and were ruminated to fine particle size before being passed. Materials with specific gravity less than 1.0 are ruminated extensively and are passed slowly. As specific gravity of plastic particles increase, rumination of particles is decreased and passage is increased. Particles with specific gravities between 1.17 and 1.42 pass most rapidly. Increasing specific gravities further results in a decline in passage and a further lowering of rumination of particles. Natural hay and fresh forages are hydrated in the rumen, which causes functional specific gravity to increase. Some factors that affect rate of change of functional specific gravity of forages have been investigated. Small particle size, autoclaved rumen fluid, buffer solutions, and specific salts increased the rate of change of functional specific gravity of particles. Understanding of these factors may enable us to make better decisions in managing ruminant productions systems.     

Crystallization of some anorthite-diopside glass precursors

Anorthite and diopside have been obtained from complete devitrification of glasses belonging to the quaternary system MgO-CaO-Al₂O₃-SiO₂. Microstructure, the natural trend of the nucleation mechanism and kinetic studies on the crystallization phenomenon have been investigated by means of optical and electron microscopies, thermal and thermomechanical techniques and X-ray powder diffractometry. All the glasses investigated show a complete crystallization starting from a simple surface nucleation process. The activation energy for the crystallization process proved to be higher than that for viscous flow, leading to an important aspect modification in the sample during ceramization. Thermal stability and physical properties of both glass and glass-ceramic materials have been tested, suggesting the possible use of these materials in industrial application.     

ESD–RF co-design methodology for the state of the art RF-CMOS blocks

This paper describes an approach to design ESD protection for integrated low noise amplifier (LNA) circuits used in narrowband transceiver front-ends. The RF constraints on the implementation of ESD protection devices are relaxed by co-designing the RF and the ESD blocks, considering them as one single circuit to optimise. The method is applied for the design of 0.25 μm CMOS LNA. Circuit protection levels higher than 3 kV HBM stress are achieved using conventional highly capacitive ggNMOS snapback devices. The methodology can be extended to other RF-CMOS circuits requiring ESD protection by merging the ESD devices in the functionality of the corresponding matching blocks.     

Finite element analysis of helicoidal waveguides

The purpose of the paper is to propose an efficient method to compute propagation modes in helicoidal waveguides. An helicoidal system of co-ordinates is introduced to define the structure and to set up the problem. These co-ordinates, albeit non-orthogonal, preserve the translational invariance in a way that allows a two-dimensional finite element model similar to that of classical straight waveguides     

A prospective investigation of the impact of childhood sexual abuse on the development of sexuality.

The sexual attitudes and activities of 77 sexually abused and 89 comparison women (mean age=20.41, SD=3.38) were assessed 10 years after disclosure in a longitudinal, prospective study of the long-term effects of childhood sexual abuse. Abused participants were more preoccupied with sex, younger at first voluntary intercourse, more likely to have been teen mothers, and endorsed lower birth control efficacy than comparison participants. When psychological functioning earlier in development was examined, sexual preoccupation was predicted by anxiety, sexual aversion was predicted by childhood sexual behavior problems, and sexual ambivalence (simultaneous sexual preoccupation and sexual aversion) was predicted by pathological dissociation. Findings also indicate that biological father abuse may be associated with greater sexual aversion and sexual ambivalence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Antimutagenic activity of phenolic compounds, oligosaccharides and quinolizidinic alkaloids from Lupinus campestris seeds.

There are some foods that contain mutagenic or carcinogenic agents, some of which occur naturally and others that may be formed during preparation or cooking. Several foods such as legumes, also contain natural antimutagens and/or anticarcinogens. Lupine is one such legume that contains high amounts of protein (40%) and oils (14%). About 90 species of lupine have been reported throughout Mexico. However, the use of this crop as a source of food has been limited by the presence of antinutritional agents such as phenolic compounds (PC), carbohydrates (CH) and quinolizidinic alkaloids (Qas). It has also been suggested that consuming these compounds can affect human health and may even reduce the risk of disease. The objective of this work was to determine the effect of PC, CH and Qas, isolated and quantified from Lupinus campestris on the mutagenicity of 1-nitropyrene (1-NP) as a model mutagen and we used the Salmonella typhimurium tester strain YG1024 by the Kado microsuspension method. The results indicate that L. campestris seeds have 11 mg (+)catechin equivalent g(-1) seed coat; 120.3 mg g(-1) seeds and 2.13 mg g(-1) seeds of PC, CH and Qas, respectively. 1-NP mutagenicity was inhibited by 86% for PC, 76% for CH and 75% for Qas at concentrations of 200, 512 and 13.6 microg/tube, respectively.     

Matter Wave Solitons at Finite Temperatures

We consider the dynamics of a dark soliton in an elongated harmonically trapped Bose-Einstein condensate. A central question concerns the behavior at finite temperatures, where dissipation arises due to the presence of a thermal cloud. We study this problem using coupled Gross-Pitaevskii and N-body simulations, which include the mean field coupling between the condensate and thermal cloud. We find that the soliton decays relatively quickly even at very low temperatures, with the decay rate increasing with rising temperature.     

The size refinement of Cu crystallites under mechanical processing conditions: a phenomenological modeling approach

A phenomenological model is developed for describing the kinetics of the crystallite size refinement process of Cu powder under mechanical treatment conditions. Based on the evidence that collisions represent the elementary events of energy transfer, the rate of crystallite size decrease is related on a statistical basis to the amount of powder trapped at each collision, to the number of collisions and to the collision energy. The mathematical approach allows for identifying the approximate functional form of the kinetic curves obtained at largely different impact energies. The values of the apparent kinetic constants and of the model parameters involved can be thus estimated by fitting the model curves to the experimental data. The results obtained provide a deeper insight into the details of the crystallite size refinement process.     

Study of the hydrolysis and condensation of γ-Aminopropyltriethoxysilane by FT-IR spectroscopy

The hydrolysis and condensation reactions of γ-APS have been studied in different acid content aqueous solution by using Fourier Transform infrared (FT-IR) spectroscopy. The hydrolysis of γ-APS under the studied conditions can be followed by the increase of the ethanol band located at 882 cm⁻¹ and the decrease of the band due to the ρ(CH₃) of γ-APS molecules located at 959 cm⁻¹. Hydrolysis reaction is faster by increasing both H₂O and acid concentrations, and it is completed when 3 moles of H₂O per mole of γ-APS are used. The increase of the vibrational band located at 1146 cm⁻¹ shows that condensation of the hydrolysed γ-APS molecules take place forming linear chains in poorly cross-linked structures. Besides, both 8-membered cyclic siloxane formations and poorly cross-linked structures are formed and increase as the water and acid content are increased. On the other hand, highly connected cross-linked structures do not appear due to the steric hindrance of the non-hydrolysable aminopropyl group. The silanol band shows that hydrolysis is faster than condensation except for samples with the lowest H₂O content.