Study of the combined effects of oxidation and adsorption process in removing MTBE from wastewater

Treatment of Methyl Tert-Butyl Ether (MTBE) from wastewater supplies presents specific challenges due to the physicochemical properties of MTBE which depend strongly on its hydrophilic nature, and translate into a high solubility in water. MTBE has very low Henry‘s constant and very low affinity for common adsorbents. An investigation was carried out for the treatability of metyl tert-butyl ether (MTBE) in synthetic wastewater. In this research, experimental rig and bench-scale studies using granular activated carbon (GAC) and hydrogen peroxide (H2O2) were conducted to observe the treatability of MTBE in synthetic wastewater. An experimental rig was built up that consist of three conjugated system. Subsequently, MTBE was amended to the H2O2 and air flow, followed by adsorption treatment with GAC. Generally, the major finding suggests that the longer cycle pulsation time (3 minutes open valve + 5 seconds closed valve) with air flow rate at 6 L/min over the synthetic wastewater caused a greater removal of MTBE. The result of this study can help to provide specific guidance into process parameter selection for treating MTBE in wastewaters. The optimum operating conditions are very important for treating the wastewater effectively in a larger scale

Angiogenesis in old-aged subjects after ischemic stroke: a cautionary note for investigators

Angiogenesis represents a form of neovascularisation of exceptional importance in numerous pathological conditions including stroke. In this context it is directly related to neuroregeneration which is seen in close proximity. However, numerous experimental data have been drawn from studies that have ignored the age criterion. This is extremely important as angiogenesis is different in young versus old subjects. Extrapolating data obtained from studies performed in young subjects or "in vitro" to old-age patients could lead to inexact conclusions since the dynamics of angiogenesis is age-dependent

A comparative study of heating elements used for the development of textile heaters

The focus of this paper is to make a comparison between five different types of conductive, heatable samples. These textile samples have been produced according to the five most important implementation techniques such as knitting, weaving, embroidery, printing and nonwoven padding. The idea is to identify a conductive option best suitable for a heating application. This study was divided into four major steps: choosing the adequate materials, swatch production, conductivity measurements and heating behaviour assessment. The first three methods use electro conductive wires as heating elements, the fourth uses conductive ink and the fifth uses carbon black coating. For all of them, resistance, current and heat distribution was measured. The results show that the best options for the development of a wearable textile heating system are the embroidered and the woven techniques, as their mechanical strength and elasticity, is sufficiently high and the fabric/substrate structure allows the insertion/deposition of different types of heating element

Bone Mineral Density in Patients with Ankylosing Spondylitis: Incidence and Correlation with Demographic and Clinical Variables

Objective: To evaluate bone mineral density (BMD) in patients with ankylosing spondylitis (AS) and determine its correlation with the demographic and clinical characteristics of AS. Patients and Methods: Demographic, clinical and osteodensitometric data were evaluated in a cross-sectional study that included 136 patients with AS. Spine and hip BMD were measured by means of dual energy X-ray absorptiometry (DXA). Using the modified Schober’s test we assessed spine mobility. We examined the sacroiliac, anteroposterior and lateral dorso-lumbar spine radiographs in order to grade sacroiliitis and assess syndesmophytes. Disease activity was evaluated using C-reactive protein (CRP) levels and erythrocyte sedimentation rate (ESR). Demographic data and BMD measurements were compared with those of 167 age- and sex-matched healthy controls. Results: Patients with AS had a significantly lower BMD at the spine, femoral neck, trochanter and total hip as compared to age-matched controls (all p<0.01). According to the WHO classification, osteoporosis was present in 20.6% of the AS patients at the lumbar spine and in 14.6% at the femoral neck. There were no significant differences in BMD when comparing men and women with AS, except for trochanter BMD that was lower in female patients. No correlations were found between disease activity markers (ESR, CRP) and BMD. Femoral neck BMD was correlated with disease duration, Schober’s test and sacroiliitis grade. Conclusion: Patients with AS have a lower spine and hip BMD as compared to age- and sex-matched controls. Bone loss at the femoral neck is associated with disease duration and more severe AS

Recent Advances Concerning Certain Class of Geophysical Flows

This paper is devoted to reviewing several recent developments concerning certain class of geophysical models, including the primitive equations (PEs) of atmospheric and oceanic dynamics and a tropical atmosphere model. The PEs for large-scale oceanic and atmospheric dynamics are derived from the Navier-Stokes equations coupled to the heat convection by adopting the Boussinesq and hydrostatic approximations, while the tropical atmosphere model considered here is a nonlinear interaction system between the barotropic mode and the first baroclinic mode of the tropical atmosphere with moisture. We are mainly concerned with the global well-posedness of strong solutions to these systems, with full or partial viscosity, as well as certain singular perturbation small parameter limits related to these systems, including the small aspect ratio limit from the Navier-Stokes equations to the PEs, and a small relaxation-parameter in the tropical atmosphere model. These limits provide a rigorous justification to the hydrostatic balance in the PEs, and to the relaxation limit of the tropical atmosphere model, respectively. Some conditional uniqueness of weak solutions, and the global well-posedness of weak solutions with certain class of discontinuous initial data, to the PEs are also presented.Comment: arXiv admin note: text overlap with arXiv:1507.0523

Global Existence and Regularity for the 3D Stochastic Primitive Equations of the Ocean and Atmosphere with Multiplicative White Noise

The Primitive Equations are a basic model in the study of large scale Oceanic and Atmospheric dynamics. These systems form the analytical core of the most advanced General Circulation Models. For this reason and due to their challenging nonlinear and anisotropic structure the Primitive Equations have recently received considerable attention from the mathematical community. In view of the complex multi-scale nature of the earth's climate system, many uncertainties appear that should be accounted for in the basic dynamical models of atmospheric and oceanic processes. In the climate community stochastic methods have come into extensive use in this connection. For this reason there has appeared a need to further develop the foundations of nonlinear stochastic partial differential equations in connection with the Primitive Equations and more generally. In this work we study a stochastic version of the Primitive Equations. We establish the global existence of strong, pathwise solutions for these equations in dimension 3 for the case of a nonlinear multiplicative noise. The proof makes use of anisotropic estimates, $L^{p}_{t}L^{q}_{x}$ estimates on the pressure and stopping time arguments.Comment: To appear in Nonlinearit

Primary Proton Spectrum of Cosmic Rays measured with Single Hadrons

The flux of cosmic-ray induced single hadrons near sea level has been measured with the large hadron calorimeter of the KASCADE experiment. The measurement corroborates former results obtained with detectors of smaller size if the enlarged veto of the 304 m^2 calorimeter surface is encounted for. The program CORSIKA/QGSJET is used to compute the cosmic-ray flux above the atmosphere. Between E_0=300 GeV and 1 PeV the primary proton spectrum can be described with a power law parametrized as dJ/dE_0=(0.15+-0.03)*E_0^{-2.78+-0.03} m^-2 s^-1 sr^-1 TeV^-1. In the TeV region the proton flux compares well with the results from recent measurements of direct experiments.Comment: 13 pages, accepted by Astrophysical Journa

A distributed optimization method for the geographically distributed data centres problem

The geographically distributed data centres problem (GDDC) is a naturally distributed resource allocation problem. The problem involves allocating a set of virtual machines (VM) amongst the data centres (DC) in each time period of an operating horizon. The goal is to optimize the allocation of workload across a set of DCs such that the energy cost is minimized, while respecting limitations on data centre capacities, migrations of VMs, etc. In this paper, we propose a distributed optimization method for GDDC using the distributed constraint optimization (DCOP) framework. First, we develop a new model of the GDDC as a DCOP where each DC operator is represented by an agent. Secondly, since traditional DCOP approaches are unsuited to these types of large-scale problem with multiple variables per agent and global constraints, we introduce a novel semi-asynchronous distributed algorithm for solving such DCOPs. Preliminary results illustrate the benefits of the new method

CONSTRUCTION EVOLUTION OF DEEP SOIL LOOSENING EQUIPMENT IN ROMANIA IN THE COUNTRY SPECIFIC SOIL CONDITIONS

This paper presents the main achievements of the largest manufacturers of deep soil loosening machines and equipment, highlighting the specific characteristics of each device, so that they achieve a very good job loosening in depth, using an low energy source for the same working width