bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling of kinetic interface sensitive tracers reactive transport in 2D two-phase flow heterogeneous porous media
Authors: Tatomir Alexandru , Zhou Dejian , Gao Huhao , Dimache Alexandru-Nicolae , Iancu Iulian , Sauter Martin
Published: February 2019

Fluid-fluid interfacial area plays an important role for mass- and energy-transfer processes across the interface which is relevant in several hydrogeological and engineering applications, e.g. enhanced oil-gas recovery, CO2 storage in geological formations, unconventional geothermal systems, contaminant removal, etc. Kinetic interface sensitive tracers were designed to determine the size of the interface between two fluids by undergoing hydrolysis at the fluid-fluid interface. This study investigates by means of numerical modelling the influence of heterogeneity on the KIS tracer breakthrough curves in six idealized scenarios (S1-S6). It is an extension of the previous work conducted in “one-dimensional” column experiments by Tatomir et al. (2018) [1]. The changes in interfacial area are created by inclusion of heterogeneities at the Darcy-scale. The results show that KIS tracers can be used in two-dimensional experimental setup and can provide information about the size and dynamic evolution of interfacial area. Therefore, this is a first step for the dimensioning of an experimental flume.
Efficiency of tube settler on removal of roagulated particles
Authors: Al-Dulaimi Sofyan , Racoviţeanu Gabriel
Published: February 2019

Tube settler systems are one of the practical applications of the shallow sedimentation theory, which was originally developed to improve the performance of conventional sedimentation systems. The efficiency of these systems depends on multiple variables. In this paper, the influence of the tube settler unit at different inclination angles of 60°, 54°, and 48° and at different surface loading rates 2.4 to 0.42 m3/m2.h upon the coagulated particles has been investigated. A laboratory model has been designed and constructed for this purpose, which basically consists of coagulation-flocculation unit followed by tube settler unit. Tube settler unit consists of four separate circular tubes of 27mm inner diameter, with a length of 150cm each. Through the results, tube settler showed high efficiency in removing coagulated particles resulted from the chemical treatment of meat industry effluents. With respect to removal efficiency, it was observed that the change in the surface loading rate had a greater effect than the change in the inclination angle of the tubes. Also, the results indicated that there was a significant improvement in the flow pattern with the reduction in the Reynolds number, within the sedimentation unit, especially in the upper and lower zones of the tubes.
Numerical modelling of a hemp concrete wall
Authors: Costantine Georges , Maalouf Chadi , Moussa Tala , Polidori Guillaume , Kinab Elias
Published: February 2019

In a global warming context associated to the abuse of energy consumption, actual researches focus more and more on reducing energy costs in the building sector. This target could be achieved by using innovative building materials, such as hemp concrete, due to its positive impacts on thermal and environmental levels. The aim of this work is to carry out a numerical study of a hemp concrete wall subjected to several indoor and outdoor conditions of temperature and relative humidity using the program object oriented SPARK. The hygrothermal behaviour of the wall is investigated taking into account heat and moisture transfer within the wall as well as hysteresis phenomenon between the sorption and desorption curves and their temperature dependency.
Hygric behaviour of a clay-Typha bio-based material for building
Authors: Niang Ibrahim , Maalouf Chadi , Moussa Tala , Samin Etienne , Mai Ton Hoang , Gaye Salif
Published: February 2019

This study deals with the impact of the amount and granulates type of Typha Australis on the hygric performance of building material based on clay. Three compositions are tested: Two of them have the same proportion of granulate but differ by their morphology (transversal or longitudinal cut of the plant). The third composition contains less Typha granulates resulting from the transversal cut. Hygric properties are experimentally, such as permeability, sorption isotherms, and moisture buffering value. Results show an influence of the Typha granulate and its volume content on the hygrothermal properties of the material due to the porosity.
State of art regarding to quantify the consequences associated with building response to an earthquake shaking
Authors: Majdi Ali , Văcăreanu Radu Sorin
Published: February 2019

Earthquake loss estimation (ELE) refers to the analysis and study of the possible effects of an earthquake in a region or population and quantifies the consequences of the earthquake. The objective of this study is to provide an insight into earthquake loss estimation for the most common approaches by seeking to survey the current methodologies for quantifying the earthquakes' negative effects. Naturally, peoples search about desirable approaches to estimate of earthquakes costs and losses which are not predetermined to subsist as usual. Other issues related to those approaches are endeavor to achieve the state of art to quantify the earthquakes consequences, the aspects of a building's response to earthquake. The aspects that will be characterized in this research are: 1) Input data like building information (Structure system, location, occupation, etc.), earthquake hazard; 2) Analysis methods; 3) Output data. ELE methods are categorized in different ways depending on one or more parameter. ELE approaches into two groups (1-a shocked building stock in a specific city or settlement, 2-specific building or structure). The varying and common use have been observed when selecting the approaches of this research. The methods and tools that used in the exploration include QLARM, SELENA, ELER, HAZUS, SLAT and FEMA P-58.
The effect of sodium percarbonate dose on the reduction of organic compounds in landfill leachate
Authors: Muszyńska Joanna , Gawdzik Jarosław , Sikorski Mikołaj
Published: February 2019

The paper discusses the issue of using classic Fenton’s reagent modification for pre-treatment of leachate from a landfill in Janczyce (Świętokrzyskie Voivodeship, Poland) – sodium percarbonate (2Na2CO3·3H2O2) was used as an alternative source of hydrogen peroxide, and hydrated iron sulphate ((II) FeSO4·7H2O) was the source of iron ions. The tests were carried out at initial process pH = 3, for different doses of the Fe2+ catalyst (ranging within 100÷5400 mgFe/L), and for mass ratio iron (II) to sodium percarbonate – 1:3. Three doses were selected after this stage, for which the following parameters were examined: the effect of initial process pH ranging between 2 and 4, the effect of oxidation process duration (30÷150 min.), and the effect of the ratio Fe2+ to sodium percarbonate (1:3, 1:5 and 1:7). The values of selected parameters (pH, COD, TOC) in leachates, both before and after the treatment process have been determined according to applicable standards. Completed tests have proven, inter alia, that the proposed implementation of the Fenton’s method with sodium percarbonate may be an effective alternative for hydrogen peroxide as an oxidiser; with an increasing dose of the 2Na2CO3.3H2O2, the improvement in landfill leachate remediation efficiency measured by decreasing TOC and COD values reaches certain extent only; the process modified with sodium percarbonate may be effective already at pH=4.
Sustainable formation of urban development on the example of the primary real estate market in Krakow
Authors: Butryn Krzysztof , Jasińska Elżbieta , Kovalyshyn Oleksandra , Preweda Edward
Published: February 2019

Due to the high demand on the housing market, it may seem that every investment will find buyers’ interest and the key is its economic dimension. Meanwhile, in the Krakow real estate market, one can observe the trend of SMART market creation, in which the added value is the quality of life of residents of a given investment, especially in terms of using renewable energy sources and ensuring a well-organized space around the investment. The implementation of intelligent energy networks and the widespread use of renewable energy sources will result in more efficient energy transfer, waste recycling, faster identification of the threat and repair after a possible failure. Using, for example, the resources of the National Fund for Environmental Protection and Water Management, the implementation of ecological solutions is not related to the excessive price of such investments, and guarantees a higher quality of life for new owners. The article presents good practices in the design of housing estates in the city of Krakow. One of such closed settlements is "Osiedle Fi", whose location guarantees good public transport, additionally underground parking places a lot of green areas outside, positively affecting the microclimate of the area. The buildings are made of natural materials and the common parts of the property are illuminated from solar energy. The use of renewable energy sources favors both the environment and reduces the cost of maintaining the property. Rainwater is also used. The next smart housing estate is "Osiedle Ozon". It is a comfortable housing estate with functional land development. Among its main attributes, it is worth mentioning a lot of greenery and naturally diversified terrain. There were used plant species, which have the ability to catch harmful chemicals or dust from soil and air. In this work, a statistical analysis was conducted to compare the prices of housing properties in these two selected settlements to the prices of real estate in the area, indicating statistically insignificant differences in the economic aspect, with significant differences in the quality of life of the potential buyer.
The impact of linear investments on the spatial structure of agricultural regions
Authors: Preweda Edward
Published: February 2019

Linear investments cause irreversible changes in the existing shape and way of using the land located alongside it. In the case of the construction of the highway, these lands are mostly located in rural areas and prior to construction, they were used mostly in agriculture. Losses resulting from such investments affect the natural environment and landscape. Along the impact zone wind conditions change, also exhaust emissions and noise increase. Investors try to avoid the design of wide protection zones of greenery, due to the cost of buying a larger area of land and they usually use it only when it is necessary. Severe ecological losses result from land degradation, disturbances in the drainage system and changes in water relations. Such investments also have a negative impact on the profitability of agricultural holdings, in particular organic farms. The market value of land adjacent to the motorway is also decreasing. Often, on both sides of the motorway there remain land with a small area, access to the ground is difficult or even impossible. In order to reduce the negative impact of linear investments on the spatial structure of agricultural areas, infrastructure integration is carried out. The implementation of consolidations related to the construction of motorways in Poland is not a common and frequent phenomenon, which lacks concrete plans and schemes of actions. The paper presents the objectives of consolidation in the area of the village of Szczepanow in the Lesser Poland Voivodeship.
Combined effects of irrigation management and nitrogen fertilization on soft wheat productive responses under Mediterranean conditions
Authors: Oliveira Patrícia , Patanita Manuel , Dôres José , Boteta Luis , Palma José Ferro , Patanita Maria Isabel , Guerreiro Isabel , Penacho José , Costa Maria Natividade , Rosa Elizabete , Tomaz Alexandra
Published: February 2019

To evaluate water-nitrogen interactions on irrigated wheat production, it is important to know: the dose, the fractioning, and the most recommended period of fertilizers application; the best irrigation volumes and schedules for meeting the crop requirements, ensuring the minimum leaching risks, to obtain the highest yields and quality of the grain, while achieving high water and nitrogen use efficiencies. This study evaluated the interactive effect of irrigation and nitrogen fertilization, with conventional and enhanced efficiency fertilizers, on yield, irrigation water use efficiency and grain quality of soft wheat. For this purpose, two trials were carried out during the 2016/2017 in Beja, Alentejo, under two irrigation strategies: D1 (100% of crop evapotranspiration – ETc - throughout the cycle) and D2 (100% of ETc only at four stages: beginning of stem extension; booting; heading; grain filling). In one trial, enhanced efficiency N fertilizers were applied through 6 splitting treatments. In the other, conventional N fertilizer was applied through 5 splitting treatments. The results suggest that, on one hand, early applications of advanced efficiency fertilizers do not compromise the crop yield and, on the other hand, the availability of nitrogen in the booting stage is important to obtain higher grain protein content.
The use of natural soil for the treatment of secondary effluent in a northern climate
Authors: Szpaczyński Janusz A.
Published: February 2019

The aim of this study was to evaluate atomizing freeze crystallization as a valuable option for land application of pre-treated wastewater. Process factors, such as the concentration of nitrogen compounds, phosphorus and conductivity have been adopted as parameters of concern and were used to assess the effectiveness of the freeze crystallization process. Five monitoring wells were installed to control the ground water quality at the site and at its boundaries. It was found that there is no dissolved phosphorus in the ground water. In most measurements, available phosphorus for plants was not detected at a soil depth greater than 50 cm. NO3--N in ground water from the up gradient well and from the down gradient wells was not detected in most sampling events. There was a small increase of NO3--N near the location of the main snowpack, but it was always lower than the drinking water standard. Total ammonia as N in the up gradient control well was at the same level as in the down gradient well. Unfortunately, higher conductivity was reported in all down gradient wells. These conductivity values did not imply risks for vegetation yields or the texture of soil. It was concluded that the method of freezing effluent in the form of man-made snow proved to be effective for cold climate land application treatment.
Determining the possibility of using selected composts to remove aqueous solutions from zinc ions in concentrations of up to 1000 mg.L-1
Authors: Kupich Iwona , Madeła Magdalena
Published: February 2019

The high sorption capacity of compost indicates that it can be a cheap alternative to the currently used sorbents, also in the case of heavy metals. The sorption of zinc from aqueous solutions with the use of the selected compost types not meeting standards was carried out in accordance with the batch method in the constant contact conditions of a liquid (100 mL) and a solid (5,0 g) when the concentrations of Zn2+ were 100, 250, 500, 750 and 1000 mg·L-1. The efficiency of the process decreased with an increasing Zn2+ concentration and was strongly dependent on the quality of the compost and the composition of the initial compost mixture. For the highest concentration of zinc, the best efficiency (nearly 70%) was obtained in case of the commercial compost, while the lowest one (only 25%) in the case of the compost made only from green waste and prepared in a garden compost bin. The experimental results were described using the Freundlich isotherms and the obtained equation parameters show the adsorption process. It was found that compost can serve as an efficient sorbent with regard to zinc ions.
Impact of silver nanoparticles on wastewater treatment in the SBR
Authors: Madeła Magdalena
Published: February 2019

The commonly application of nanoparticles (NPs) in commercial and industrial products inevitably increases their release into the natural environment which poses a threat to human health and ecosystems. A recent study of nanoparticles in wastewater treatment showed that most NPs are retained in the equipment used for biological wastewater treatment. The aim of the study was to determine the effects of silver nanoparticles (Ag NPs) on wastewater treatment in the SBR bioreactor. The effluent from the SBRs was analyzed for total organic carbon (TOC), suspended solids (SS), pH and total silver. Microbial observations of activated sludge were made and, on this basis, the Madonia biotic index was specified. After nanoparticles were added, the composition of microorganism communities of the activated sludge changed, and the largest community was the one of creeping ciliates. The efficiency of the effluent treatment measured by the concentration of TOC removal showed that Ag NPs were found to have remarkable effects on TOC removal in the SBR. The obtained results showed that purified wastewater included a low concentration of Ag nanoparticles. The main removal pathway of Ag NPs was via sorption as well as possible aggregation and sedimentation onto the sludge.
Ozone water treatment in small water purification plants in Poland – Mszana Dolna case study
Authors: Pawełek Jan , Bergel Tomasz
Published: February 2019

The study analyzed possibilities of using ozone for water treatment in supply stations that provide water to small water supply systems. We analyzed a containerized water treatment plant (CWTP) in Mszana Dolna, located in Małopolska region, with a nominal production of 15 m3∙h-1. The plant uses a two step pressure filtration system with indirect water ozonation prior to active carbon filters. The treated water meets all the requirements set for drinking water. A cost analysis was also carried out to find out whether using this type of technology in small water supply stations in Poland is economically justified. The calculations were based on water production and its costs in 2017. The unit cost of water amounted to 0.59 and 0.77 EUR∙m3 for the variant taking into account a nominal water production and a hydraulic load of the station in 2017 that reached 58.7% f a nominal load.
The impact of Bacillus megaterium on the solubilisation of phosphorus from sewage sludge
Authors: Ciopińska Joanna , Bezak–Mazur Elżbieta , Stoińska Renata , Szeląg Bartosz
Published: February 2019

The aim of this work was to analyse the influence of Bacillus megaterium bacteria on the solubilisation of phosphorus in a sewage sludge. The tests were carried out for two different temperature conditions, i.e. 21 and 36ºC. In the experiment, lasting 23 days, the course of phosphorus solubilization under the influence of a changing population of bacteria was determined using Golterman’s speciation analysis. This method allows to estimating the fraction of bioavailable phosphorus in the tested samples. The obtained results allow one to state that the population size of Bacillus megaterium bacteria changes, while the intensity of these changes depends on temperature and organic acids produced in metabolic processes change the pH of the environment, which affects phosphorus solubilisation and its speciation. The increase in the population of bacteria is accompanied by the increase in bioavailable phosphorous forms, and thus the release of phosphorus contained in the form of sparingly soluble forms in soil. The above fact is extremely important when considering the use of sewage sludge for natural purposes.
Development of the Polish geothermal sector in the light of current possibilities of financial support for a geothermal investment
Authors: Sowiżdżał Anna , Tomaszewska Barbara , Chmielowska Anna
Published: February 2019

Geothermal energy is an internal heat of the Earth, that is a prospective and sustainable source of renewable energy. In Poland, despite having significant amount of low-temperature geothermal resources, its share in the national energy mix remains marginal but growing. Currently, the utilisation of geothermal resources is related to hydrogeothermal resources, that are used mainly in space heating, recreation and balneotherapy. Nevertheless, the indication of potential electricity production is under research. The utilisation of geothermal resources entails a plenty of environmental benefits that are particularly important in the context of the present pollution problem. Therefore, the development of the geothermal energy sector is of relevant importance and with appropriate legal and financial conditions it may have a bearing on improvement of the environment’s quality and, ipso facto, living in Poland. Thus, this paper presents numerous possibilities of obtaining a financial support for investments in geothermal energy sector. Selected funding and financial backing systems currently available in Poland are discussed. The importance of opportunity of obtaining a financial support for an investment as one of the crucial factors for the geothermal sector development is emphasised. Moreover, the examples of installations implemented in the country in the context of obtained funding are presented.
Treatment Wetland effluent quality improvement by usage sorbents of various origin
Authors: Kasprzyk Magda
Published: February 2019

TWs are finding as low-cost and also effective system to treat domestic wastewater. The aim of this study is to find suitable adsorbing material for application in an additional treatment unit where treatment wetlands do not provide sufficient PO43- reduction level. Material M1 is a fine-grained by-product of thermal treatment of carbonate-siliceous rock (opoka) with high content of calcium carbonate CaCO3 in temperature 700°C. Particular disadvantage of material M1 can be very high level of pH (11-12) and causing alkaline solution. Material M2 is lanthanum-modified bentonite (LMB) and was already used for reducing content of phosphorus compounds in lakes and other water bodies to treat effects of eutrophication process. Lanthanum-modified bentonite consists mostly SiO2 and Al2O3 (~80%). The study was conducted on effluent from small (60 pe) treatment wetland (TW) in northern Poland where Hybrid Treatment Wetland (HTW) system was provided. Sorption capacity of material M1 was low and equal 0.9 mg/g. For material M2 this parameter reached value of 2.1 mg/g. Lanthanum-modified bentonite (M2) has shown better abilities to reduce phosphates from wastewater that material M1 – material containing mostly calcium oxide. Also performed study revealed that presence of others contaminations in wastewater is causing difficulties in phosphates removal.
An optimised system for energy monitoring and data acquisition in substations/domestic applications using IoT
Authors: Rama Krishnan V. Badri , Sandepudi Keerthana , Gazal Shaista
Published: February 2019

The rising demand and tariff rates of electric power have derived the need to develop innovative methods to monitor, manage, economize and save energy. Energy monitoring and conservation are pre-eminent today because of the imbalance between power generation and demand. This paper proposes the outline and application of electrical energy measurement by an Arduino micro-controller that is used to calculate the power consumed by any individual electrical device. The main intention of the presented energy meter is to monitor, acquire and interpret the power consumption data online by integrating smart plugs, sensors at the device level and upload it to the server using IoT based communication protocol. Thus, this project enables the consumer to act accordingly to save power and to render a reliable power supply by making maximum use of energy sources in the cheapest ways.
A case Study on wired and Wireless charger standards in India for Electric Vehicle Application
Authors: M N Shivanand , Maruthi Y. , Babu Bobba Phaneendra , Vuddanti Sandeep
Published: February 2019

India has taken major step in adopting the electric vehicle by means of FAME Scheme (Fast Adoption and Manufacturing of Electric Vehicles), a government initiative. ARAI (Automotive Research Authority of India) and DHI (Department of Heavy Industry) have published standardization protocol for both EV charging infrastructure. Many of those standards are derived from the SAE (Society of Automotive Engineers) Internationals and IEC (International Electrotechnical Commission). USA, Europe and China are also following the same standards to build the EV (Electric Vehicle) infrastructure. This paper provides the Indian standards to build EV charging infrastructure and comparing it with other countries. Glimpses on energy demand for electric vehicles in Indian market. It also provides the demanding wireless power transfer technology in EV’s. Status of Standards provided by the industry on wireless power transfer. Factors that are necessary to be considered before drafting the standards for WPT.
Communication between PHEV’s and Smart Grid using Zigbee Protocol
Authors: R Karthik Rao , P Sai kiran , Babu Bobba Phaneendra
Published: February 2019

Plug-in-hybrid electric vehicles commonly known as PHEV’s are hybrid electric vehicles that use rechargeable batteries for operation. Since PHEV’s run on electric batteries, they require charging after the charge reaches a certain minimum level. The batteries can be charged using external sources usually a smart grid. This requires a wireless technology that can be used to send the information of the battery charge to the smart grid so that it can be charged. This paper is a detailed description of how this communication can be achieved using the ZigBee wireless technology. The battery level information can be sent to the smart grid using this technology and the smart grid operator can then decide whether the PHEV needs charging or not. If not, the battery can be used to provide Vehicle-to-grid (V2G) services i.e. the charge from the vehicle can be sent back to the grid depending on the will of the vehicle owner. Thus, in this way a system can be developed where in both the PHEV driver and the grid operator can benefit.
V2G Transfer of Energy to Various Applications
Authors: Sree lakshmi Dr. G. , Divya G. , Sravani G.
Published: February 2019

In today’s world, there is a need of verge of significantant transformation in Electrical Power System. The Vehicle-to-Gird (V2G) concept optimizes this transformation. The PEV typically has a higher capacity Energy Storage System (ESS). Each PEV stores approximately 5-40kWh of energy. This energy can be transferred to the Vehicle-to-Grid (V2G), Vehicle-to-Home (V2H) and Vehicle-to-Building (V2B) as most of the time the vehicle is kept in parking as idle. This paper presents the concept of V2G technology, their classifications, battery storages and types of batteries for V2G.
Non-isolated Modified Quadratic Boost Converter with Midpoint Output for Solar Photovoltaic Applications
Authors: Ravivarman Shanmugasundaram , Natarajan Karuppiah , Raja Gopal Reddy B
Published: February 2019

This paper presents a boost DC-DC converter topology with non - isolated high gain and output midpoint, to boost the voltage obtained from solar photovoltaic panels. The three-level boost converter is coupled to the output port of the single-switch quadratic boost converter to derive the proposed converter topology. The voltage gain of the proposed converter is greater than that of the classical boost converter. The voltage stress on the switches of the proposed converter is equal to half of the converter output voltage. Static analysis, operating modes, experimental waveforms in continuous current conduction and discontinuous current conduction modes are shown. A 520 W prototype converter was implemented in the laboratory and its results are presented.
Peak Detection Control Strategy based STATCOM for Suppression of Power Quality Problems
Authors: Bangarraju J. , Rajagopal V. , Sharada V. , Lakshmaiah K.
Published: February 2019

This paper explains about control of VSC using uni-polar switching based Static Compensator (STATCOM) using Peak Detection Control Strategy for elimination of PQ Problems. The proposed STATCOM are operated in PFC (Power Factor Correction) mode and ZVR (Zero Voltage Regulation) mode. Under these operation modes of STATCOM is able to suppression of harmonics, PFC at source, reactive power compensation, load balancing and compensation of neutral current. A non-isolated star/three individual single- phase transformers are connected at PCC (Point of Common Coupling) to mitigate neutral current. The Peak Detection Control Strategy is simple to implement for estimating switching pulses for VSC. This peak detection control strategy based STATCOM is modelled, simulated results are validated using MATLAB R2013b.
Acoustic analysis methods for particle identification with superheated droplet detectors
Authors: Felizardo M. , Reis M. , Fernandes A. C. , Kling A. , Morlat T. , Marques J.G.
Published: February 2019

A superheated droplet detector (SDD) consists of a uniform dispersion of over-expanded, micrometric-sized halocarbon droplets suspended in a hydrogenated gel, each droplet of which functions as a mini-bubble chamber. Energy deposition by irradiation nucleates the phase transition of the superheated droplets, generating millimetric-sized bubbles that are recorded acoustically. A simple pulse shape validation routine was developed in which each pulse is first amplitude demodulated and the decay constant then determined through an exponential fit. Despite this, low amplitude (< 3 mV) events embedded at naked eye in the noise level are not counted for calibration purposes with neutron and alpha sources. The solution found was to filter the data with a low band-pass filter in the region that the bubbles nucleate (typically from 450 to 750 Hz). After this, a peak finding algorithm to count all the events was implemented. The performance demonstrates better than a factor 40 reduction in noise and an extra factor 10 reduction with the filtering application. The lowering of noise and discovery of low signal amplitudes by the acoustic instrumentation and acoustic analysis permits a capability of discriminating nucleation events from acoustic backgrounds and radiation sources and, having a 95% confidence level on identifying and counting events in substantial data sets like in calibrations.
Design, Construction and In Situ Testing of a Muon Camera for Earth Science and Civil Engineering Applications
Authors: Lázaro Roche Ignacio , Bitri Adnand , Bouteille Simon , Decitre Jean-Baptiste , Jourde Kevin , Gance Julien , Truffert Catherine , Gaffet Stéphane
Published: February 2019

The MUST2 (MUon Survey Tomography based on Micromegas detectors for Unreachable Sites Technology) camera is based on a thin Time Projection Chamber read by a resistive Micromegas. This innovative combination presents interesting distinctive features compared to existing muon detection technologies. It allows a wide angular acceptance of the detector with a low weight and compact volume, well adapted for confined spaces or underground operation. The current work presents the results obtained during the calibration measurements at the reference site, the Low Background Noise Laboratory (LBNL). Preliminary results from field measurement campaign carried out at the dam overlooking the village of Saint-Saturnin-les-Apt (South-East of France) are presented and discussed.
A first inventory of the labile biochemicals found in Avignon groundwater: can we identify potential bacterial substrates?
Authors: Rousset Ludivine , Gillon Marina , Duport Catherine , Clavel Thierry , Lagrée Marie , Traikia Mounir , Panagiotopoulos Christos , Berge Odile
Published: February 2019

Groundwater is a major source of water for irrigation of vegetables, especially in the Mediterranean basin. Contamination of aquifer by pathogens has been responsible for numerous disease outbreaks worldwide. Several studies reported that groundwater dissolved organic matter (DOM) can serve as a source of carbon and energy for heterotrophic metabolism of pathogens. In this study, we aimed to investigate the DOM composition of groundwater collected at Avignon. Six liters of groundwater were filtered (0.2 µm) and freeze-dried following appropriate cleaning procedure. The bulk analyses of powder sample were performed using 1D and 2D nuclear magnetic resonance spectroscopy and liquid chromatography coupled with mass spectroscopy. Several components were found at concentrations around 1 µM and comprise: (i) humic and fulvic acids originated from land-derived material or soils and, (ii) various acids, esters and alcohols of different sizes including acetate, lactate and formate, these may result from microbial metabolism. In conclusion, the Avignon groundwater DOM contains a heterogeneous mixture of dissolved organic components with a rather low potential bioreactivity based on the low level of labile biogeochemicals such as carbohydrates.
RF CMOS Oscillators Design for autonomous Connected Objects
Authors: Haddad Fayrouz , Rahajandraibe Wenceslas , Ghorbel Imen
Published: February 2019

Voltage controlled oscillator (VCO) is an integral part of IoT wireless transceiver components. In this paper, VCOs operating around 2.4 GHz have been designed in CMOS technology. The relation between their components and specifications is studied for their performance optimization. Ultra-low power, less than 270 µW, has been obtained, while performing a frequency tuning range of about 10% between 2.1 and 2.4 GHz. Investigations on phase noise performance have been also achieved.
A global modeling approach of the leakage phenomena in dielectrics
Authors: Postel-Pellerin Jérémy , Micolau Gilles , Chiquet Philippe , Joelson Maminirina , Decitre Jean-Baptiste
Published: February 2019

Thanks to its low noise level, the LSBB environment provides particular environment to carry out high quality electrical characterizations. In this paper, we propose a complete modeling approach of the experimental results from our experimental microelectronic setup. The tested device is a Metal Oxide Semiconductor (MOS) floating gate capacitor which can be found in electrostatic non volatile memories such as Flash. The main idea is to characterize and model the leakage current through the tunnel oxide. We proposed, in a previous work, a model for charge loss considering a fractional Poisson process, involving only two parameters, expressed as a Mittag-Leffler (ML) function. Here, we also propose a combo of Fowler-Nordheim (FN) and Poole-Frenkel (PF) models for leakage currents, based on tunnel effect transport through the oxide. It gives the leakage current on a medium-to-long scale of time while the ML model can possibly take into account a shorter time step. The perspective is to find a relationship between these different models, used in various fields, to propose a generic model of phenomena involving leakage in complex and porous materials at different scales of time and space.
Measure and analysis of 4H-SiC Schottky barrier height with Mo contacts
Authors: Zhang Teng , Raynaud Christophe , Planson Dominique
Published: February 2019

Current–voltage (I–V) and capacitance–voltage (C–V) characteristics of Schottky Mo/4H-SiC diodes have been measured and analyzed as a function of temperature between 80 and 400 K. The I–V characteristics significantly deviate from ideal characteristics predicted by the thermionic emission model because of the inhomogeneity of Schottky contact. After a brief review of the different existing models, the main parameters (ideality factor, barrier height, and effective Richardson constant) of both diodes have been extracted in the frame of a Gaussian barrier height distribution model, whose mean and standard deviation are linearly dependent on voltage and temperature, as well as in the context of the potential fluctuation model. The results are compared with the values extracted by C–V and the values in the literature. A link is established between these two models. Diodes of different I–V  characteristics, either identified as single barrier or double barrier, have been analyzed by Deep Level Transient Spectroscopy (DLTS) to investigate the deep level defects present. No noticeable difference has been found.
Single-Pass Cladding Process Using Hot-wire Gas Metal Arc Welding Technique
Authors: Suntiniwat Pattanawit , Warinsiriruk Eakkachai , Joy-A-Ka Sutep
Published: February 2019

The aim of this study is to improve cladding process productivity by high production rate with low dilution process by specifying technique as hot-wire GMAW process. The base metal of carbon steel A516 Gr70 was cladded by austenitic stainless steel 309LSi for creating a buttering layer and stainless steel 308LSi for hot-wire filler for topping a cladding layer in a one-pass run. The studied parameters this experiment consist of the feeding ratio of hot wire feeding speed per GMAW wire feeding speed and travel speed. Welding phenomenon during welding was observed by CCD camera with specifying the optical device to see the appropriate condition. The result showed the hot-wire GMAW cladding process could reduce cycle time 3.5 times compare with conventional FCAW cladding process. Moreover, dilution of this process could decrease lower than 15% with acceptable FN 3 on the top of weld surface. Therefore, single pass cladding process achieved by using this method with low dilution by still keep microstructure capability.
The Influence of Heat Input to Mechanical Properties and Microstructures of API 5L-X65 Steel Using Submerged Arc Welding Process
Authors: Suryana  , Pramono Agus , Muda Iskandar , Setiawan Ade
Published: February 2019

API 5L-X65 steel is the type of high strength low alloy (HSLA) steel, widely used in the manufacture of pipe. Submerged arc welding (SAW) is widely used for the fabrication of the pipe, the extent of use submerged arc welding caused it could be done automatically and high reliability. The results of the welding process will lead to differences and changes in the microstructure in heat affected zone (HAZ) and weld metal that will affect the mechanical properties of the output, so as to obtain good welding results required the selection of welding parameters accordingly. As the use of the heat input during welding is very important influence on the mechanical properties and microstructure of the weld. The purpose of this study to determine the effect of heat input on the microstructure, hardness and toughness of welds in submerged arc welding. Welding currents used were 200, 300, 400 and 500 Ampere with a voltage were used 25, 27 and 30 Volt. The results showed that the higher heat input will result in a growing area of HAZ region width and grain size increased. Highest hardness values are the results of the weld heat input with a low of 244.69 HVN caused by the rapid cooling rate of the weld area. The highest toughness values are the results of the highest heat input that was dominated by acicular ferrite phase.
Innovate Method for Friction Stir Welding of Al-Mg-Si Alloy Thin Plate
Authors: Fu Li , Liu Fenjun
Published: February 2019

Al-Mg-Si (6061-T6) alloy with 0.8 mm thick plate was welded successfully by use of high speed friction stir welding (FSW) technology. The microstructural characteristics and mechanical property of the butt joints prepared by high speed FSW were analyzed in detail, the influence of welding parameters, fixture condition and after welding heat treatment were also explored. The results shown that sound surface topography and defect-free bonding interface were observed in the nugget zone (NZ). The microhardness of the as-welded joint was lower than that of the base metal because of the welding heat effect. Compared with the conventional speed FSW, the number of β-Mg2Si, Al2CuMg and Al8Fe2Si precipitated phases existed in the high speed FSWed NZ increased, which made the microhardness in the NZ improved significantly. The rod-shaped precipitates (Mg2Si) have the greatest influence on the microhardness distributions. The maximum tensile strength of 301.8 MPa, which was 85.8% of the base metal, was obtained at high rotation speed of 8000 rpm and fast welding speed of 1500 mm/min. The tensile strength of the ultra-high speed FSWed butt joints were improved significantly by post-weld artificial aging, with a maximum joint efficiency of 90.4%.
Fatigue Life Prediction of Welded Joint by Microstructure-based Simulation
Authors: Shiraiwa Takayuki , Briffod Fabien , Enoki Manabu
Published: February 2019

This paper proposes a numerical framework to predict fatigue life on welded joints by integrating several computational techniques. The framework consists of five steps: i) materials properties estimation; ii) welding simulation using thermo-mechanical finite element method; iii) macroscopic stress field analysis under cyclic loading; iv) mesoscopic stress field analysis using crystal plasticity finite element method (CPFEM); v) analysis of fatigue crack growth. The total number of cycles to failure is eventually obtained by the sum of initiation life calculated by CPFEM and propagation life calculated by X-FEM. A fatigue life of butt joint is evaluated by the proposed method. The results demonstrated the possibility of evaluating the fatigue life and its scattering by the proposed framework.
Residual Stress Assessment of PWMT Butt Joint with 10mm HSLA S460G2+M Steel using HFMI/PIT FEA and XRD
Authors: Nordin Noridzwan , Mat Muhd. Faiz , Manurung Yupiter H. P. , Saidin Salina , Andud Dahia
Published: February 2019

This research involves the assessment of the residual stress of HSLA S460G2+M steel on butt joints which were welded using manual GMAW and further treated with HFMI/PIT process. The assessment began by manually welding 3-pass butt joint specimens using GMAW with ER80S-N1 as filler wire and mixed shielding gas (80%Ar-20%CO2). The weld toe of the specimens was then treated using HFMI/PIT operating at a peening frequency of 90Hz and a pneumatic pressure of 6 bar. The residual stress on the surface of treated and untreated specimens were measured using the X-ray diffraction method. Following the measurements, a simulation was conducted using non-linear solver FEA software MSC Marc/Mentat. The HFMI/PIT treatment process was simulated using a quasi-dynamic model approach for the force of the hammering pin. A customized spring function applying a consistent force onto the surface of the weld joint was modelled with this method. The material behavior model used for the specimen was based on a simplified Hensel-Spittel model obtained from the material database software MatILDa. It is observed that the HFMI/PIT-treated specimens induces compressive residual stress on the weld toe that is beneficial for fatigue life and the simulation demonstrated good agreement with the actual process.
Preliminary Assessment of 22Cr and 15Cr Materials Selection for CO2 Enhanced Oil Recovery Program
Authors: Prabowo Harris , Pratesa Yudha , Ulum Reza M. , Munir Badrul , Soedarsono Johny W.
Published: February 2019

Enhanced Oil Recovery (EOR) program to increase oil production from mature fields are now being implemented in Indonesia amid concern over the continuous decrease of oil production level. The mature fields and EOR process have the tendency to carry relatively high impurities components (CO2, H2S, chloride ions) that results in early corrosion occurrence, creating damages in the subsurface equipment (wellhead, tubing, Xmas tree, etc). In Java area with 0.09 TSCF potential gas reserves, 49.3 MMSTB oil and + 23% CO2 content, such amount of CO2 gas and possibility of H2S and chloride from the reservoir will require a higher grade material than the conventional carbon steel. This paper discuss the preliminary materials selection process in the program plan based on the existing condition. The material selection based on the evaluation of closest field data, literature review as a comparison, material, and fluid analysis test. Duplex 22Cr-15 Cr materials are the main study in the paper as the candidate for the tubing material in high CO2, high H2S and chloride environment. The polarization result in 27°C and 50°C showed that the chrome 22 %Cr material had pitting tendency in chloride ion 25,000 ppm, while at high temperature (80 °C) the pitting tendency shifted to 5,000 ppm of chloride ion.
Effects of High Frequency Mechanical Impact on Fatigue Life of Semi-Automated Gas Metal Arc Welding (GTAW) of HSLA Butt Weld
Authors: Saidin Salina , Andud Dahia , Manurung Yupiter H. P. , Mat Muhd. Faiz , Nordin Noridzwan , Leitner Martin
Published: February 2019

This paper deals with a comprehensive investigation of fatigue life enhancement on semiautomated Gas Metal Arc Welding (GTAW) butt weld joint which is found almost everywhere in Malaysia welding structure steel sectors. The selected material in this study was high strength low alloy steel S460G2+M commonly used extremely in steel structure due to its outstanding mechanical properties. In this investigation, the method for joining the butt weld was conducted by unprofessional welder using semi-automated GMAW. At first, suitable welding parameters were identified and formulated into welding procedure specification (WPS) qualification conforming to AWS D1.1 standard. The test specimens were prepared and tested to ensure the welding quality. Further, the HFMI using Pneumatic Impact Treatment (PIT) technique were applied at the weld toe of the butt weld as tool for fatigue life enhancement. To investigate the influence of HFMI/PIT on the fatigue strength, the specimens were undergone fatigue test using universal fatigue machine using a constant amplitude loading. Finally, the comparison of the fatigue strength of as welded and treated specimens to indicate the beneficial influence of the treatment. Yes, the conduction by unprofessional welder using semi-automatic GMAW, the findings showed the improvement of fatigue strength and slope of S-N curves. In addition, the fracture location of test specimen shows physically affected by shifting from critical weld transition to base metal. The tensile test and hardness value also showed a slight difference as compared to untreated specimens.
Assessment of Offshore Piping Composite Repair Technology for Life Extension Program Case in Pertamina Hulu Energy West Madura Offshore
Authors: Arifin Muhamad , Cahyono Arif , Putra Idam , Munir Badrul
Published: February 2019

The pipe work repair method such as clamps and pipe connector as the use of metallic repair component have been used for maintenance and repair application in oil and gas industry and cover the most common types of defect to pressurize system like internal and external corrosion and also cover situations where the damage is severe. On the other hand with a process safety precausion and production concern, in oil and gas facility the use of metallic repair is very challenging and most of the time will come as last option scenario. Composite repair which are now increasing in application to pipe repair situations may come as a solution. This paper provides assessment of offshore piping composite repair for life extension program of pressure system in West Madura Offshore. Assessment come to a conclusion that the composite repair at field PHE WMO which operate on envelop of 700 psi and temperature range of 20°C-80°C are still in good condition and retain the integrity of the asset, from where then the repair is considered to extent its lifetime.