bluuebunny/crossref_metadata_2025_split huggingface dataset:
1H and13C NMR investigation of oils extracted from exotic fruits
Authors: Siciliano C , Napoli A , Aiello D , De Luca P , Temperini A 
Published: August 2019

AbstractExotic fruit seeds are waste of industrial preparation of foods and human consumption. The contents in terms of nutrients of oils extracted from exotic fruit seeds are not fully understood, and they remain object of study. We propose a practical, inexpensive, qualitative and quantitative approach based on the use of1H and13C NMR spectroscopy for the fatty acid chain profiling of these oils. The composition of eleven seed oils was investigated. The amounts of linoleic (from 3.5% in Rambutan to 84.6% in Feijoa), oleic (from 6.9% to 68.7% in Papaya), and saturated fatty acid chains (from 7.9% in Feijoa to 49.5% in Rambutan) were determined. The total contents of unsaturated fatty acid (MUFA and PUFA) chains in oils ranged from 37.5% in Mangosteen to 91.5% in Feijoa. The oils were characterized by saturated/unsaturated (SFA/PUFA) ratios ranging from 0.08 to 1.07, with values which were superior to that commonly reported for extra virgin olive oil. These ratios are potentially favorable for human health. The ANOVA test showed the model to be remarkably significant (p < 0.05). Spectral data agreed those reported in the literature for conventional methods. Although linolenic acid was not detected in all oils, their fatty acid chain profiles make them desirable in terms of nutrition and as alternative energy sources.
Influence of slag powder in the cement mortar mixes on the characteristics of compactness and freeze –thaw strength
Authors: Nicula L M , Corbu O , Iliescu M 
Published: August 2019

Abstract
Worldwide, there is a clear imperativeness to reduce the consumption of non-renewable raw materials. The aim of the research is to obtain new ecological materials with applicability in the construction field, but also to efficiently manage these by-products by eliminating it completely and re-introducing it into the economic circuit. We envisaged the use of slag products as a material cementitious characteristics or as artificial aggregates, so that materials embedded in construction produce as little environmental impact as possible. After cooling, the blast furnace slag products was used in the new mortar mixes in two forms: in the form of a powder product milled from the granulated slag, and in the form of an aggregate made of non-granulated slag, sorted to the sized of 0/4 mm. Ground-granulated slag in the form of a powder below 63 μm was used as an addition to the cement mass, and the newly obtained artificial aggregate, sorted to 0/4 mm, was used in various percentages for replacing the natural aggregates in the control mix. The results show that the combined use of slag powder as an addition to the cement mass and artificial slag aggregates, regardless of the percentage of substitution of Natural aggregates in the mortar mortar mix, has led to the development of new mortar mixes with higher compaction than the control mortar. The higher filling rate due to the use of ground slag has influenced the increase of compressive strengths and freeze-thaw strengths from the repeated freeze-thaw action for new cement mortar mixes with blast furnace slag, as compared to the control mortar mix.
Process of magnetizing bulk amorphous alloys Fe43+xCo29-xY8B20 (x=0 or 5)
Authors: Nabialek M , Jeż B , Jeż K , Pietrusiewicz P , Bloch K , Gondro J , Abdullah M M A B , Sandu A V 
Published: August 2019

Abstract
The paper presents the results of investigations of the structure and magnetic properties of Fe43+xCo29-xY8B20 bulk amorphous alloys (x = 0 or 5). Alloy samples were made using injection a liquid alloy into a copper mold. The produced materials were characterized by soft magnetic properties, i.e. a high saturation of magnetisation value (about 1.15T) and a relatively low coercive field value (below 100 A/m). Increasing the cobalt content in alloys affected the high Curie temperature (around 700K). On the basis of H. Kronmüler's theory, an analysis of the magnetisation process in area so-called the approach to ferromagnetic saturation was carried out. The analysis showed that the impact on the process of magnetizing the produced materials have linear defects in the form of pseudo-dislocation dipoles.
Phases and compounds composition analyze of ZnMgCa biodegradable alloy
Authors: Popescu S (Dobriţă) , Stanciu S , Cimpoeşu R , Istrate B , Ştirbu I , Ioniţă I , Prisecariu B A 
Published: August 2019

Abstract
Besides biocompatible materials, a new class of metallic materials with medical applications dedicated to specific traumas is that of biodegradable materials. Zinc-based materials are mentioned as the ‘Calcium of the XXI century’. Zn has been considered as one of the newest promising biodegradable metallic metals together with Mg-based and Fe-based alloys. A new experimental composition of ZnMgCa alloy was obtained using an induction furnace from high purity zinc, magnesium and calcium materials. The material chemical compounds and phases were determined using EDS Bruker detector and XRD X’Pert equipment in molded state of the alloy. Microstructure of the alloy was determined using scanning electron microscopy and the distribution of constituents using VegaTescan software.
Obtaining and characterisation of high entropy alloys used for medical applications
Authors: Geantă V , Voiculescu I , Ştefănoiu R , Codescu M , Kelemen H , Pavel G , Vlădescu A , Sandu V A 
Published: August 2019

Abstract
The experimental CrFeMoNbTaTiZr alloys were designed based on the extremely low bio-toxicity of the chemical elements. They are currently used as a basis for alloying of classical alloys used in medical device manufacturing. From this alloying system, were obtained in a Vacuum Arc Remelting (VAR) equipment six alloys: CrFeMoNbTaTi, CrFeMoNbTaZr, CrFeMoTaTiZr, CrFeTaNbTiZr, CrTaNbTiZrMo and FeTaNbTiZrMo. The microstructural analysis of the obtained alloys have been performed by optical and SEM microscopy. The microhardness tests show results in the range of 575 – 1337 HV0.2 / 10. In order to improve the mechanical properties heat treatment procedures have been applied.
The active screen influence of edge effect in plasma nitriding
Authors: Perju M C , Axinte M , Nejneru C , Cimpoesu N , Ţugui C A 
Published: August 2019

Abstract
Plasma nitriding thermochemical treatment has a beneficial effect regarding wearing resistance. One of the disturbing effects for plasma nitriding is edge effect, which modifies the properties uniformities on the edges of the treated part. Edge effect is found in the intersection area of the two surfaces adjacent negative light. The active screen has a role in modifying the plasma field for the entire part, so also in the edges areas. This overcomes and reduces the negative technological consequences of the edge effect. Different analysis for the subjected areas were made, also on the surface parts but also in depth of the parts, in it’s section.
Performance of local fly ash geopolymers under different types of acids
Authors: Burduhos Nergis D D , Vizureanu P , Andrusca L , Achitei D C 
Published: August 2019

Abstract
A new class of ceramic materials, known as geopolymers, possess comparable or even higher mechanical and chemical properties than ordinary Portland cement-based materials. Because geopolymers can be used in a wide variety of areas, from civil engineering applications to decorative objects manufacturing, they can get in contact with different types of acidic corrosive substances. The degradation degree depends mostly on the acidic solution concentration and the exposure time. Due to the interaction between the geopolymer compounds, Al, Si and Fe ions solubility and the corrosive environment substance, there may follow severe consequences on the material mechanical properties. These consequences are highly related to the geopolymers three-dimensional structure degeopolymerization. The performance of geopolymers under severe environmental condition depends on the raw material, mineralogical composition and activation method. The aim of this paper is to present the effects of nitric acid, sulfuric acid and hydrochloric acid exposure on the local fly ash geopolymers compressive strength and microstructure.
In vitro corrosion behavior of Ti-Mo-W alloys in artificial saliva
Authors: Ghica Ş I , Cotruţ C M , Buzatu M , Antoniac I V , Geantă V , Buţu M , Petrescu M I , Ştefănoiu R , Ungureanu E , Iacob G , Ionescu R N 
Published: August 2019

AbstractTitanium and its alloys are preferred materials used for medical devices manufacturing due to their specific properties. The corrosion behavior in artificial saliva of the newly developed Ti-Mo-W alloys, with elastic modulus closer to the human bone value was studied by means of linear polarization technique in the following steps:i)measurement/monitoring of open circuit potential (EOC) over 6 hours;ii)tracing linear polarization curves from ±200 mV (vs. OCP) - Tafel plots, with a scan rate of 0.167 mV/s. Electrochemical tests were performed according to ASTM G59-97 (2014)using a Potentiostat/Galvanostatto which a low current interface (LCI) was coupled. The tests were performedin Fusayama Meyer artificial saliva with a pH of 5.2 at the human body temperature (37±0.5°C) which mimic the oral environment. The results indicate that the alloys Ti15Mo7W and Ti15Mo11W have better corrosion behavior than Ti6Al4V.
Accumulation of stress induced martensite in Fe43.5Mn34Al15±xNi7.5∓X shape memory alloys
Authors: Apostol V , Lohan N M , Mihalache E , Comăneci R I , Cimpoesu N , Pricop B , Popa M , Bujoreanu L G 
Published: August 2019

Abstract
Fe43.5Mn34Al15Ni7.5 shape memory alloys (SMAs), have drawn considerable attention from the part of scientific community due to its superelastic behaviour, stable over a large thermal range (from -50 to +150°C) [1]. After cyclic heat treatment, solution treatment and ageing, the specimens became oligocrystalline and were reinforced by NiAl nanoprecipitates. The typical thermomechanical processing routine, before cyclic heat treatment of FeMnAlNi alloys, involves hot rolling, annealing and cold rolling [2]. The present paper discusses the effects of ± 1.5 at. % aluminium substitution with nickel, by correlating tensile behaviour with microstructural observations. The SMA specimens with chemical composition Fe43.5Mn34Al15±1.5Ni7.5∓1.5 were subjected to tensile tests, comprising loading-unloading cycles, based on which recoverable strain and energy storage efficiency were calculated. Considering that, in each cycle, a permanent strain was obtained, it follows that not all of the amount of stress induced martensite completely reversed to austenite, but a small part of it was accumulated in each cycle. By optical and scanning electron microscopy, the microstructural changes correlated with stress induced martensite accumulation were emphasized, while considering the effects of ± 1.5 at. % Al substitution with Ni.
A probabilistic model for predicting grain growth processes in alloys
Authors: Réti T , Felde I , Réger M , Tóth L , Fried Z 
Published: August 2019

Abstract
This paper deals with a possible generalization of the traditional grain growth kinetic functions. A novel probabilistic model devoted to the grain growth prediction in alloys is presented. It is based on the extension of the traditional power law kinetic equation proposed by Beck. The Beck’s isothermal kinetic equation is defined as D(t)=A*exp(-E/RT)*tm where D(t) is the grain size (diameter), t is the time, E is the activation energy, A is the preexponential factor, m is the time exponent, R is the universal gas constant and T is the absolute temperature. The novel probabilistic model proposed is based on the concept of the mixture of probability density functions. In this model it is assumed that during grain growth the activation energy (E) is not constant, but its distribution is determined by the initial grain morphology of alloys. More exactly speaking, it is supposed that the activation energy is a random variable which is characterized by the probability density function g(E) of the activation energy. By using appropriately selected probability density functions, different types of generalized grain growth kinetic equations can be established. Based on computer simulations, the application of the extended grain growth kinetic models is demonstrated by examples.
Optimization of the objective function –surface quality by end-milling dimensional machining of some aluminum alloys
Authors: Ţîţu M A , Pop A B , Ţîţu Ş , Pop G I 
Published: August 2019

Abstract
In the aerospace industry, the milling of aluminum alloy parts is a machining process with the primary purpose of removing high volumes of material. Aluminum alloys are materials that have relatively good machinability, which helps the process because many of the components of the aircraft are of high dimensions. These parts have many pockets more or less deep, and the removal by cutting off about 90% of the initial volume of the workpiece is a matter of consideration. The manufacturing process is protracted and involves long semi-finishing and finishing operations, so it is recommended that any researcher who begins and finishes an experimental study should do it base on a specific experimental plan. Mathematical statistics techniques and methods are used, but also optimization methods that lead to a rational choice of process parameters, process input data and objective functions that need to be improved. This scientific paper presents applied research based on an extremely pertinent active experiment that has led to some practical solutions applied in the aerospace industry worldwide. The dedicated objective function on which the study conducted in this case was the mean arithmetic deviation of the surface profile. The independent variables were chosen by the concrete application of a dispersion analysis applied to the milling process, namely the cutting speed, the cutting depth and the feed per tooth. Interpretation of the results was performed by a graphical evaluation of the normality of the data distribution, by presenting the histogram responses as well as by the dispersion diagrams. It was used for a better correlation a 3D graphical analysis that followed the Ra variation of the mean arithmetic deviation of the machined surface profile under the influence of the cutting parameters and the independent variables respectively. The obtained conclusions led to the validation of the experimental model and the application of the research presented within an aerospace industry organization with important global valences.
Treatment of industrial slag zinc ferrite by zeolitic sludge
Authors: De Luca P , Bernaudo I , Candamano S , Siciliano C , Macario A 
Published: August 2019

Abstract
The study reports the results in the removal efficiency of the metals released by zinc ferrite in aqueous systems, using a zeolitic sludge as an ion exchanger The so-called zinc ferrite is an industrial waste produced during the treatment of minerals for zinc extraction. The zeolitic sludge used in the experimental campaign is a by-product that derives from industrial processes and contains a combination of synthetic zeolites such as 4A (LTA) and 13X zeolite (FAU). Initially, different systems have been prepared, with predefined weight ratios of zeolitic sludge/zinc ferrite/water. The systems were analyzed, at different times, by plasma mass spectrometry (ICP-MS) that allowed to measure the variation of concentration of Fe, Mg, Ca, Zn, Mn, Pb, Na, K ions. Zeolitic sludges were efficient for the total absorption of Pb and Zn ions.
Brackish water treatment with carbon nanotubes
Authors: Foglia P , Vuono D , Siciliano C , Napoli A , Nagy J B. , De Luca P 
Published: August 2019

Abstract
The present work aims to experiment the action of carbon nanotubes (MWCNTs) in the removal of sodium chloride from aqueous systems, not using them as a membrane but dispersing them directly in solution, in order to evaluate possible applications in the desalination of brackish water. For this purpose, different aqueous systems have been prepared by varying the sodium chloride concentration and the amount of carbon nanotubes dispersed therein. The systems were stirred for scheduled times and then the amount of residual sodium chloride was measured by drying, after filtration, the systems and weighing the dry residue. In the final part of the experimentation, after having identified the best system, the tests were carried out directly on sea water and using different types of carbon nanotubes such as not oxidized (MWCNTs) and oxidized (MWCNTS-ox) ones.
Investigation of mode II interlaminar fracture toughness of lignocellulosic laminated specimens – an experimental and numerical approach
Authors: Baba M N , Ulea M , Roşca I C , Mihălcică M , Scutaru M L 
Published: August 2019

Abstract
Mode II interlaminar fracture toughness of lignocellulosic laminate composite materials made of beech veneer with urea formaldehyde resin and rye flour was investigated using the end notched flexure specimens (ENF). In order to determine the critical value of the strain energy release rate GIIc
associated with the interlaminar crack onset, the experimental data analysis was conducted by means of a mixed mode bending device in conjunction with a compliance calibration approach for data reduction. The interlaminar crack propagation under pure mode-II loading was also simulated by finite element analysis using general contact in Abaqus/Explicit, with Virtual Crack Closure Technique (VCCT) as fracture criterion. Good agreements between the load-displacement curves obtained through the use of finite element analyses and the experimental testing results were obtained.
Influence of process parameters for Selective Laser Melting on the roughness of 3D printed surfaces in Co-Cr dental alloy powder
Authors: Baciu A M , Bejinariu C , Corăbieru A , Mihalache E , Lupu–Poliac M , Baciu C , Baciu E R 
Published: August 2019

Abstract
Modern technologies of Additive Manufacturing type allow for the obtaining of the metal components specific to medical prosthetics in the best conditions. Selective Laser Melting (SLM) method is frequently used in dental medicine since there is an obvious trend to replace the classical casting techniques especially for non-noble Co-Cr alloys. According to the values of processing parameters (SLM) there will be parts having different roughness of the exterior surfaces. The conducted studies analysed the influences exercised by three process parameters (laser power – P, scan speed – vscan and exposure time – te) on roughness amplitude expressed by value (Ra). By combining the three distinct values adopted for each parameter we made nine sets of lamellar samples on whose non sandblasted surface, surface sandblasted once and surface sandblasted in two successive stages we carried out roughness measurements. Based on the results obtained for (Ra) parameter we formulated some recommendations for the technological parameter values that may provide surface roughness adequate to the subsequent destination of the processed parts (SLM).
Heat treatment behavior of alternator shafts steels
Authors: Ghiban B , Bran D T 
Published: August 2019

Abstract
The present paper analyzes properties such as the hardness, the tensile and toughness behaviour and the microstructure for multiple bars of C40 and C45 steel used for shafts in alternators. The materials have been manufactured by rolling processes, followed by normalization treatments or forging processes followed by normalization treatments. Heat treatments are performed on steels to produce different microstructural phases that affect the mechanical properties. Microstructural changes during austenite decomposition depend on the transformation temperature region and cooling rate. Over the years, many experimental studies have been performed to reveal the microstructural changes during isothermal holding or continuous cooling of austenite for various kinds of steels. The isothermal transformation (IT) diagram, which is also called the time-temperature-transformation (TTT) diagram, and the continuous cooling transformation (CCT) diagram have been developed to graphically characterize the decomposition transformation as a function of time and temperature. However, when these diagrams are based on experimental measurements, several limitations are present. Each diagram is limited because the temperatures at which specific transformations occur can vary due to several factors, such as: the chemical composition of steel, the solid solution condition in the austenite prior to cooling and transformation, the presence of precipitates in austenite, the prior austenite grain size, and the applied stresses during the transformation.
Influence of surface roughness and current intensity on the adhesion of high alloyed steel deposits - obtained by thermal spraying in electric arc
Authors: Haraga R A , Bejinariu C , Cazac A , Toma B F , Baciu C , Toma S L 
Published: August 2019

Abstract
In this paper the surfaces of some steel samples, low alloyed, were covered by electric arc thermal spray with a steel layer, high alloyed, containing FeNiCrSiB-WC/TiC, using a core wire. In order to study the influence of process parameters on obtained deposits, the surface roughness and the intensity of electric current varied on three levels and the rest of the technological parameters were kept constant. The microstructural characteristics, chemical composition, physical and mechanical properties of the obtained deposits were investigated by SEM analysis of microhardness and by X-ray diffraction. The deposition porosity was investigated by optical microscopy. The adhesion of the layers was investigated by the traction test. Studies have shown that by increasing the intensity of the electric current respectively the arc temperature, the deposition porosity decreases by 23,4%, the microhardness HV and the adherence of the samples subjected to the test increases. The FeNiCrSiB-WC/TiC layers, deposited on low alloyed steel support, can be considered as convenient solutions for obtaining hard, wear-resistant surfaces.
Optimization of processing parameters for graphitization of oil palm trunk waste at lower heating temperature
Authors: Karim N A , Ghazali C M R , Ramli M M , Sandu AV , Chirila E , Abdullah M M A 
Published: August 2019

Abstract
Previously synthetic graphite was produced at higher temperature which is around 2,500 °C in complex processing method. The method bear the name of the scientist whose discover the synthetic graphite namely “Acheson Process”. However, via pyrolysis process, in controlled heating condition, and specific heating rate by utilizing oil palm trunk waste, synthetic graphite was managed to produce at much lower heating temperature. In this research, the heating temperature were varied in the range of 500 °C, 800 °C, and 1,000 °C. The heating rate applied also varied, from 5 °/min to 10 °/min and 20 °/min. After heating treatment, the samples were characterized using X-ray Diffraction (XRD) and analysed by X’Pert Highscore Plus software. Graphitic nature of the synthetic graphite produced was further supported by RAMAN analysis. The morphological study was carried out by using Scanning Electron Microscope (SEM). Based on the analysis, optimum processing parameters was optimized. It is at the temperature of 800 °C and at the heating rate of 20 °/min.