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Projects to Reduce the Coastal Erosion of the Romanian Black Sea Area

Abstract

The entire Romanian Black Sea coastline is subject to erosion under the conditions of coastal dynamics changing. The problem the Romanian coastal area is facing is the accelerated number of conflicts between coastal development and coastal erosion. The purpose of this article is to present the projects realized and proposed for the protection and rehabilitation of the Romanian coastal area. The implementation of projects from non-reimbursable European funds to reduce erosion in the coastal area of the Romanian Black Sea coast aims to protect and improve the quality of the environment and the standard of living.

Open access
Proper Infrastructure Design at High Vertical Loads, Nearby Waterfront Structures

Abstract

Hence economic growth requires more and more investments in the harbor area, especially nearby waterfront structures, a special attention must be taken into account regarding proper infrastructure design for structures with high vertical loads. At the same time, we have to consider the good behavior of the new design structures and also their impact on the existing nearby waterfront infrastructure. Being adjacent to waterfront structures and due to the limited available space, these structures are typically tall and narrow, and exert average soil pressures on the order of 300KPa. These loads can only be accommodated by ground with an adequate bearing capacity. This publication presents case studies of waterfront projects like grain silos storage facility. Available results for the certification and monitoring of the works are also presented, as well as other considerations based on the author’s experience.

Open access
The Quest for the Ideal Darcy-Weisbach Friction Factor Equation from the Perspective of a Building Services Engineer

Abstract

The calculation of the friction factor involved in the Darcy-Weisbach equation has a key role in the accurate assessment of distributed head losses. For the turbulent flow regime, this friction factor was mathematically expressed in the form of the Colebrook-White (C-W) equation, widely accepted by engineers and scientists. Nevertheless, the C-W equation is an implicit one and must be solved using numerical methods. This is a major disadvantage for the average engineer, who always prefers an explicit equation which could be easily integrated into his familiar spreadsheet environment. The present paper is investigating some of the most used explicit alternatives to the C-W equation, with respect to several case scenarios taken from typical Building Services hydraulic calculations.

Open access
Removal of Methylene Blue by Activated Glass Foams with TiO2 in Dark and Simulated Solar Light

Abstract

The effect of germanium trapezoidal profile shape on the direct current (DC) current gain (βF), cut-off frequency (fT) and maximum oscillation frequency (fMAX) of silicon-germanium (SiGe) hetero-junction bipolar transistors (HBTs) has been investigated. The energy balance (EB), hydrodynamic (HD) and drift-diffusion (DD) physical transport models in SILVACO technology computer aided design (T-CAD) simulator were used. It was found that the current gain values using energy balance model are higher than hydrodynamic and much higher than those corresponding to drift-diffusion. Moreover, decreasing the germanium gradient slope towards the collector side of the base enhances the maximum oscillation frequencies using HD and EB models whilst, they remain stable for DD model.

Open access
A Screening Method by Gas Chromatography-Mass Spectrometry for the Quantification of 24 Aerosol Constituents from Heat-Not-Burn Tobacco Products

Summary

A screening method allowing the quantification of 24 aerosol constituents using gas chromatography-mass spectrometry has been developed to assess the aerosol chemistry of heat-not-burn tobacco products.

The aim of this method was to quantify phenol, o-cresol, m-cresol, p-cresol, catechol, resorcinol, hydroquinone, 1,3-butadiene, isoprene, benzene, acrylonitrile, toluene, pyridine, styrene, 1,2-propylene glycol, menthol, 2-furanmethanol, acrylamide, naphthalene, nicotine, acetamide, quinoline, triacetin, and glycerine in the aerosol emitted by heated tobacco products. The aerosol was generated by an electrically heated tobacco system (PMI’s Heated Tobacco System (THS 2.4)) with one single aerosol collection method, using the Health Canada smoking regimen and analyzed with two analytical methods.

The method was validated according to the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use and the Association of Official Analytical Chemists guidelines.

A regression model based on a linear relationship between concentration and response ratio with a 1/x weighting factor was selected for phenol, o-cresol, m-cresol, p-cresol, 1,3-butadiene, isoprene, benzene, acrylonitrile, toluene, pyridine, styrene, 2-furanmethanol, acrylamide, naphthalene and acetamide. A quadratic regression model with a 1/x weighting factor was chosen for catechol, resorcinol, hydroquinone, 1,2-propylene glycol, menthol, nicotine, quinoline, triacetin and glycerine. Coefficients of variation for repeatability were determined between 7.9% and 17.8% and for intermediate precision between 8.1% and 19.9%.

The matrix effect of the heated tobacco aerosol extract was assessed by performing a recovery study, where the aerosol extracts were spiked at different concentrations for the compounds to be analyzed. In addition, the mainstream smoke from 3R4F reference cigarettes was analyzed, and results were compared with previously published studies. The method was successfully validated, providing data consistent with published data and it was shown to be selective, precise and accurate.

Open access
Solutions of the Dirac Equation in a Bardeen Black Hole Geometry

Abstract

In this paper we study the Dirac equation in the geometry of a (regular) Bardeen black hole. We will focus on finding new analytical solutions in the vicinity of the black hole horizon. These solutions can be used with the asymptotic solutions (derived in a previous paper) to compute numerical phase shifts that define the scattering amplitudes.

Open access
The Specifics of Use of Composite Materials in Consolidation of Historical Monuments

Abstract

The use of composite systems in protecting, preserving and maintaining historical monuments has become more and more used. There are several consolidation procedures with fiber-reinforced polymeric polymers that can be applied as required or on the basis of the basic material (concrete, masonry, wood, etc.). Besides the many advantages it provides, the application of composite systems in the rehabilitation of heritage buildings and historical monuments requires minimal workmanship. More and more cities are actively involved in the rehabilitation and preservation of heritage buildings and historical monuments by launching good practice guides to preserve local cultural heritage by applying composite elements as robust as possible without the need to modify the overall dimensions of the buildings through a classic covering.

Open access
Spin Coating Method Fabricated of In2O3 Thin Films

Abstract

In this work, the In2O3 thin films have been fabricated using a spin coating technique; this technique was prepared in our laboratory. The effect of the layer times (3, 5, 7 and 9 times) on optical and structural properties was investigated. In2O3 thin films were fabricated by dissolving 0.2 M of the indium chloride dehydrate InCl3.2H2O in the absolute H2O. The In2O3 thin films were crystallized at a temperature of 600 °C with pending time of 1 hour. The optical property shows that the prepared In2O3 thin films for 3 and 5 times have a transmission of about 85 %. The maximum bandgap energy was 3.69 eV for 5 times and the lowest Urbach energy was 0.47 eV for 9 times. From XDR all fabricated In2O3 thin films having one diffraction crystal plan is (222) peak intensity, this attribution have good crystalline structure with minimum crystallite size of the (222) plan is 59.69 nm. The prepared In2O3 thin films can be used in photovoltaic applications due to the existing phase and higher transmission.

Open access
Study on irradiated D-mannose isolated from cranberry

Abstract

The stable EPR signal produced by ionizing radiation in crystalline D-mannose (C6H12O6) and separated from cranberries (Vaccinium oxycoccus) was studied. The isothermal heating of irradiated sample at 95°C for 10 minutes (melting point of D-mannose is 132°C) resulted in the modification and simplification of the EPR signal involved. The isotropic quartet has been recognized in the EPR signal of heat-treated sample. Molecular structure of the isotropic quartet identified in the complex EPR signal of D-mannose crystallite is proposed.

Open access
Study on the Non-Compliant Landfill from Bârlad in Vaslui County

Abstract

This paper presents a part of a comprehensive study on non-compliant landfill in Vaslui County. We have been tracking the subsidences taking place in the body of waste dumps and the amount of gas removed to take the best post-closure monitoring measures. In order to trace the behavior regarding the subsidence in the landfill body, there were placed in the ground 11 milestones/topographic landmarks of plastics, painted in white and red to be easily identified visually. Keeping them on the same positions made possible the analysis in the present study. Topographic surveys in the ground were performed once a month between April 2014 and September 2015. The results, interpretations and proposed solutions are presented in this paper.

Open access