bluuebunny/crossref_metadata_2025_split huggingface dataset:
A new biocompatible delivery scaffold containing heparin and bone morphogenetic protein 2
Authors: Thanyaphoo Suphannee , Kaewsrichan Jasadee 
Published: July 2016

Abstract
Silicon-substituted calcium phosphate (Si-CaP) was developed in our laboratory as a biomaterial for delivery in bone tissue engineering. It was fabricated as a 3D-construct of scaffolds using chitosan-trisodium polyphosphate (TPP) cross-linked networks. In this study, heparin was covalently bonded to the residual -NH2 groups of chitosan on the scaffold applying carbodiimide chemistry. Bonded heparin was not leached away from scaffold surfaces upon vigorous washing or extended storage. Recombinant human bone morphogenetic protein 2 (rhBMP-2) was bound to conjugated scaffolds by ionic interactions between the negatively charged SO4
2- clusters of heparin and positively charged amino acids of rhBMP-2. The resulting scaffolds were inspected for bone regenerative capacity by subcutaneous implanting in rats. Histological observation and mineralization assay were performed after 4 weeks of implantation. Results from both in vitro and in vivo experiments suggest the potential of the developed scaffolds for bone tissue engineering applications in the future.
Bioactive chemical constituents of Curcuma longa L. rhizomes extract inhibit the growth of human hepatoma cell line (HepG2)
Authors: Abdel-Lateef Ezzat , Mahmoud Faten , Hammam Olfat , El-Ahwany Eman , El-Wakil Eman , Kandil Sherihan , Abu Taleb Hoda , El-Sayed Mortada , Hassenein Hanaa 
Published: July 2016

Abstract
The present study was designed to identify the chemical constituents of the methanolic extract of Curcuma longa L. rhizomes and their inhibitory effect on a hepatoma cell line. The methanolic extract was subjected to GC-MS analysis to identify the volatile constituents and the other part of the same extract was subjected to liquid column chromatographic separation to isolate curcumin. The inhibition of cell growth in the hepatoma cell line and the cytopathological changes were studied. GC-MS analysis showed the presence of fifty compounds in the methanolic extract of C. longa. The major compounds were ar-turmerone (20.50 %), β-sesquiphellandrene (5.20 %) and curcumenol (5.11 %). Curcumin was identified using IR, 1H and 13C NMR. The inhibition of cell growth by curcumin (IC50 = 41.69 ± 2.87 μg mL-1) was much more effective than that of methanolic extract (IC50 = 196.12 ± 5.25 μg mL-1). Degenerative and apoptotic changes were more evident in curcumin- treated hepatoma cells than in those treated with the methanol extract. Antitumor potential of the methanolic extract may be attributed to the presence of sesquiterpenes and phenolic constituents including curcumin (0.051 %, 511.39 μg g-1 dried methanol extract) in C. longa rhizomes.
Olive leaf extract activity against Candida albicans and C. dubliniensis – the in vitro viability study
Authors: Zorić Nataša , Kopjar Nevenka , Kraljić Klara , Oršolić Nada , Tomić Siniša , Kosalec Ivan 
Published: July 2016

Abstract
Olive leaf extract is characterized by a high content of polyphenols (oleuropein, hydroxytyrosol and their derivatives), which is associated with its therapeutic properties. The objective of the present research was to evaluate the antifungal activity of olive leaf extract against Candida albicans ATCC 10231 and C. dubliniensis CBS 7987 strains. Minimum inhibitory concentrations (MIC) of the extract were determined by several in vitro assays. The extract showed a concentration depended effect on the viability of C. albicans with MIC value of 46.875 mg mL-1 and C. dubliniensis with MIC value 62.5 mg mL-1. Most sensitive methods for testing the antifungal effect of the extracts were the trypan blue exclusion method and fluorescent dye exclusion method while MIC could not be determined by the method according to the EUCAST recommendation suggesting that herbal preparations contain compounds that may interfere with this susceptibility testing. The fluorescent dye exclusion method was also used for the assessment of morphological changes in the nuclei of treated cells. According to the obtained results, olive leaf extract is less effective against the tested strains than hydroxytyrosol, an olive plant constituent tested in our previous study.
A study of compressibility and compactibility of directly compressible tableting materials containing tramadol hydrochloride
Authors: Mužíková Jitka , Kubíčková Alena 
Published: July 2016

Abstract
The paper evaluates and compares the compressibility and compactibility of directly compressible tableting materials for the preparation of hydrophilic gel matrix tablets containing tramadol hydrochloride and the coprocessed dry binders Prosolv® SMCC 90 and Disintequik™ MCC 25. The selected types of hypromellose are Methocel™ Premium K4M and Methocel™ Premium K100M in 30 and 50 % concentrations, the lubricant being magnesium stearate in a 1 % concentration. Compressibility is evaluated by means of the energy profile of compression process and compactibility by the tensile strength of tablets. The values of total energy of compression and plasticity were higher in the tableting materials containing Prosolv® SMCC 90 than in those containing Disintequik™ MCC 25. Tramadol slightly decreased the values of total energy of compression and plasticity. Tableting materials containing Prosolv® SMCC 90 yielded stronger tablets. Tramadol decreased the strength of tablets from both coprocessed dry binders.
Evaluation of pancreatin stability through enzyme activity determination
Authors: Terra Gleysson De Paula , Vinícius De Farias Marcus , Trevisan Marcello Garcia , Garcia Jerusa Simone 
Published: July 2016

Abstract
Pancreatin is a biotechnological product containing an enzyme complex, obtained from porcine pancreas, that is employed in treating pancreatic diseases. Experiments regarding the stability of the pharmaceutical formulation containing pancreatin were performed using standard binary mixtures with 6 excipients in a 1:1 ratio (m/m) and a commercial formulation. To accomplish these goals, samples were stored for 1, 3 and 6 months at 40 ± 1 °C and 75 ± 5 % relative humidity (RH) and 40 ± 1 °C and 0 % RH. Stress testing was also performed. All samples were analyzed to evaluate the α-amylase, lipase and protease activities through UV/Vis spectrophotometry. The results revealed that the excipient proprieties and the storage conditions affected enzyme stability. Humidity was a strong influencing factor in the reduction of α-amylase and protease activities. Stress testing indicated that pH 9.0 and UV light did not induce substantial alterations in enzyme activity.
Robust aperiodic-disturbance rejection in an uncertain modified repetitive-control system
Authors: Zhou Lan , She Jinhua , Li Chaoyi , Pan Changzhong 
Published: July 2016

Abstract
This paper concerns the problem of designing an EID-based robust output-feedback modified repetitive-control system (ROFMRCS) that provides satisfactory aperiodic-disturbance rejection performance for a class of plants with time-varying structured uncertainties. An equivalent-input-disturbance (EID) estimator is added to the ROFMRCS that estimates the influences of all types of disturbances and compensates them. A continuous-discrete two-dimensional model is built to describe the EID-based ROFMRCS that accurately presents the features of repetitive control, thereby enabling the control and learning actions to be preferentially adjusted. A robust stability condition for the closed-loop system is given in terms of a linear matrix inequality. It yields the parameters of the repetitive controller, the output-feedback controller, and the EID-estimator. Finally, a numerical example demonstrates the validity of the method.
Effect of Heat Treatment on Mechanical Properties and Microstructure Morphology of Low-Alloy High-Strength Steel
Authors: Bolanowski K. 
Published: July 2016

Abstract
The paper analyzes the influence of different heat treatment processes on the mechanical properties of low-alloy high-strength steel denoted by Polish Standard (PN) as 10MnVNb6. One of the findings is that, after aging, the mechanical properties of rolled steel are high: the yield strength may reach > 600 MPa, and the ultimate tensile strength is > 700 MPa. These properties are largely dependent on the grain size and dispersion of the strengthening phase in the ferrite matrix. Aging applied after hot rolling contributes to a considerable rise in the yield strength and ultimate tensile strength. The process of normalization causes a decrease in the average grain size and coalescence (reduction of dispersion) of the strengthening phase. When 10MnVNb6 steel was aged after normalization, there was not a complete recovery in its strength properties.
Computer Simulation of the Relationship between Selected Properties of PVD Coatings
Authors: Śliwa A. , Kwaśny W. , Sitek W. , Bonek M. 
Published: July 2016

AbstractThe possibility to apply the Finite Element Method to calculate internal stresses which occur in Ti+TiN, Ti+Ti(CxN1-x) and Ti+TiC coatings obtained in the magnetron PVD process on the sintered high-speed steel of the PM HS6-5-3-8 type. For the purpose of computer simulation of internal stresses in coatings with the use of MES, the correct model of analyzed specimens was worked out and then it was experimentally verified by comparison of calculation results with the results of computer simulation. Accurate analysis of correlations indicated especially strong dependence between internal stresses and microhardness and between microhardness and erosion resistance what created conditions for establishing the dependence between internal stresses obtained in the result of computer simulation and erosion resistance as basic functional quality of coating. It has essential practical meaning because it allows to estimate predictable erosion resistance of coating exclusively on the base of the results of computer simulation for used parameters in the process of coating manufacturing.
The Influence of Heat Treatment on the Magnetization Process (within Strong Magnetic Fields) for the Alloy: Fe61Co10Y8Cu1B20
Authors: Gruszka K. , Nabiałek M. , Błoch K. 
Published: July 2016

Abstract
Samples of Fe61Co10Y8Cu1B20 alloy were investigated in the ‘approach to ferromagnetic saturation’ region by using the Kronmüller method. The amorphous material was obtained by radially cooling the molten alloy under a protective atmosphere of inert gas. Following this manufacturing process, static magnetic hysteresis loops were measured for samples, before and after a controlled isothermal annealing process, using a LakeShore vibrating magnetometer (VSM). From analysis of the primary magnetization curves, the distribution of structural defects and the average exchange distance for these defects were determined.
Spark Plasma Sintering of Low Alloy Steel Modified with Silicon Carbide
Authors: Hebda M. , Dębecka H. , Miernik K. , Kazior J. 
Published: July 2016

AbstractThe influence of adding different amounts of silicon carbide on the properties (density, transverse rupture strength, microhardness and corrosion resistance) and microstructure of low alloy steel was investigated. Samples were prepared by mechanical alloying (MA) process and sintered by spark plasma sintering (SPS) technique. After the SPS process, half of each of obtained samples was heat-treated in a vacuum furnace. The results show that the high-density materials have been achieved. Homogeneous and fine microstructure was obtained. The heat treatment that followed the SPS process resulted in an increase in the mechanical and plastic properties of samples with the addition 1wt. % of silicon carbide. The investigated compositions containing 1 wt.% of SiC had better corrosion resistance than samples with 3 wt.% of silicon carbide addition. Moreover, corrosion resistance of the samples with 1 wt.% of SiC can further be improved by applying heat treatment.
Numerical Modeling of Copper Reduction in Fire Refining Process
Authors: Kolczyk E. , Miczkowski Z. , Czernecki J. 
Published: July 2016

Abstract
Copper reduction represents one of the steps in the process of fire refining of blister copper. Process of copper reduction with natural gas as performed in the anode furnace was modeled. Numerical analysis was conducted using the IPSA (Inter- Phase-Slip Algorithm) module of PHOENICS package and standard turbulent model k - ε. The model takes into account the liquid phase - slag and phase of natural gas which is supplied through the tuyere from the bottom of the charge. Calculations were made for two different diameters of tuyeres for supply of reducer. Based on the calculations and analysis, it was found out that the gas flow which causes strong movement in the bath guarantees homogeneous composition of the liquid copper in each process stage. Application of a tuyere with a larger diameter results in a greater intensity of the reduction process and better use of the reducer.
Studies on Cementation of Tin on Copper and Tin Stripping from Copper Substrate
Authors: Rudnik E. , Sikora P. 
Published: July 2016

Abstract
Cementation of tin on copper in acid chloride-thiourea solutions leads to the formation of porous layers with a thickness dependent on the immersion time. The process occurs via Sn(II)-Cu(I) mechanism. Chemical stripping of tin was carried out in alkaline and acid solutions in the presence of oxidizing agents. It resulted in the dissolution of metallic tin, but refractory Cu3Sn phase remained on the copper surface. Electrochemical tin stripping allows complete tin removal from the copper substrate, but porosity and complex phase composition of the tin coating do not allow monitoring the process in unambiguous way.
Protective Coatings in the Power Boilers which are Used to Combust Waste – Surfacing Anticorrosive Layers
Authors: Słania J. , Sacharz – Szewczyk A. 
Published: July 2016

Abstract
General requirements and technological solutions of incinerating plants were presented. Heat processing of waste in fluidized and stoker-fired boilers were described. A problem of corrosion and the methods of preventing it in boilers used to combust waste were shown. Materials of increased resistance to corrosion used in power industry were characterised.
Properties of Copper Doped Neodymium Nickelate Oxide as Cathode Material for Solid Oxide Fuel Cells
Authors: Lee Kyoung-Jin , Choe Yeong-Ju , Hwang Hae-Jin 
Published: July 2016

Abstract
Mixed ionic and electronic conducting K2NiF4-type oxide, Nd2Ni1-xCuxO4+δ (x=0~1) powders were synthesized by solid state reaction technique and solid oxide fuel cells consisting of a Nd2Ni1-xCuxO4+δ cathode, a Ni-YSZ anode and ScSZ as an electrolyte were fabricated. The effect of copper substitution for nickel on the electrical and electrochemical properties was examined. Small amount of copper doping (x=0.2) resulted in the increased electrical conductivity and decreased polarization resistance. It appears that this phenomenon was associated with the high mean valence of nickel and copper and the resulting excess oxygen (δ). It was found that power densities of the cell with the Nd2Ni1-xCuxO4+δ (x=0.1 and 0.2) cathode were higher than that of the cell with the Nd2NiO4+δ cathode.
Cr Poisoning On Nd2Ni0.95Cu0.05O4+δ Cathode for Solid Oxide Fuel Cells
Authors: Choe Yeong-Ju , Lee Kyoung-Jin , Hwang Hae-Jin 
Published: July 2016

Abstract
In this study, Nd2Ni1-xCuxO4+δ (x=0, 0.05, 0.1, and 0.2) layered perovskite powders were synthesized by the glycine nitrate process (GNP) and the chromium poisoning effect on the electrochemical performance of the Nd2Ni0.95Cu0.05O4+δ and La0.6Sr0.4Co0.2Fe0.8O3-δ cathodes were investigated. In the case of the LSCF cathode, the strontium chromite phase formed after the exposure of the gaseous chromium species, while there was no additional phase in the Nd2Ni0.95Cu0.05O4+δ cathode. The area specific resistance (ASR) of the Nd2Ni0.95Cu0.05O4+δ cathode did not change significantly after the exposure of the gaseous chromium species at 800°C.
Characterization of Three-Dimensional Printed Composite Scaffolds Prepared with Different Fabrication Methods
Authors: Szlązak K. , Jaroszewicz J. , Ostrowska B. , Jaroszewicz T. , Nabiałek M. , Szota M. , Swieszkowski W. 
Published: July 2016

Abstract
An optimal method for composites preparation as an input to rapid prototyping fabrication of scaffolds with potential application in osteochondral tissue engineering is still needed. Scaffolds in tissue engineering applications play a role of constructs providing appropriate mechanical support with defined porosity to assist regeneration of tissue. The aim of the presented study was to analyze the influence of composite fabrication methods on scaffolds mechanical properties. The evaluation was performed on polycaprolactone (PCL) with 5 wt% beta-tricalcium phosphate (TCP) scaffolds fabricated using fused deposition modeling (FDM). Three different methods of PCL-TCP composite preparation: solution casting, particles milling, extrusion and injection were used to provide material for scaffold fabrication. The obtained scaffolds were investigated by means of scanning electron microscope, x-ray micro computed tomography, thermal gravimetric analysis and static material testing machine. All of the scaffolds had the same geometry (cylinder, 4×6 mm) and fiber orientation (0/60/120°). There were some differences in the TCP distribution and formation of the ceramic agglomerates in the scaffolds. They depended on fabrication method. The use of composites prepared by solution casting method resulted in scaffolds with the best combination of compressive strength (5.7±0.2 MPa) and porosity (48.5±2.7 %), both within the range of trabecular bone.
Electrophoretic Deposition and Characterisation of Chitosan Coatings on Near-Β Titanium Alloy
Authors: Jugowiec D. , Kot M. , Moskalewicz T. 
Published: July 2016

Abstract
In this study, chitosan coatings were electrophoretically deposited (EPD) on near-β Ti-13Nb-13Zr alloy. The influence of colloidal solution composition and EPD parameters on the quality of chitosan coatings was investigated. It was established that the uniformity of as-deposited chitosan coatings is highly dependent on the chemical composition of the solution used for EPD, the pH, electrophoretic mobility and zeta potential of chitosan colloidal molecules, as well as EPD parameters, such as potential difference value and deposition time. The microstructure of the coatings was investigated using electron microscopy and X-ray diffractometry. The coatings 350 nm thick were homogeneous and exhibited an amorphous structure. The coatings had low hardness and Young’s modulus. The effect of surface of the substrate preparation prior to coating deposition on the adhesion of chitosan coatings to the Ti-13Nb-13Zr alloy was also investigated. The coatings exhibited good adhesion to the non-acid-etched surface of the titanium alloy.
Numerical Analysis of a Skew Rolling Process for Producing a Stepped Hollow Shaft Made of Titanium Alloy Ti6Al4V
Authors: Pater Z. , Bulzak T. , Tomczak J. 
Published: July 2016

Abstract
The paper describes a rolling process for a hollow Ti6Al4V alloy shaft used in driving systems of light trucks. The shaft is formed by skew rolling using three tapered rolls. The principle of this forming process was discussed stressing its universality due to the potential of applying it for forming various products by one set of rolls. The numerical analysis results (product shape progression in rolling, wall thickness distribution, effective strain, temperature and variations in loads and torques) confirm that the proposed technique can be used for producing hollow long shafts.
Cast Hybrid Composites Designated for Air Compressor Pistons
Authors: Dolata A. J. , Dyzia M. , Jaworska L. , Putyra P. 
Published: July 2016

Abstract
The main purpose of the investigations was to develop the phase composition of the composite assuming that the component selection criterion will be the formability of piston work surfaces during the machining. Wear resistance under the friction conditions was assumed as the additional parameter for the assessment of composite material. In the study were used AlSi7Mg/SiC+Cg and AlSi7Mg/SiC+GR hybrid composites prepared by the stir casting method.
Microstructural Aspects of Twin-Spot Laser Welding of Dp-Hsla Steel Sheet Joints
Authors: Stano S. , Grajcar A. , Wilk Z. , Różański M. , Matter P. , Morawiec M. 
Published: July 2016

Abstract
The article presents the possibility of using twin-spot laser welding (i.e. laser welding with focusing a laser beam on two spots) for making overlap joints made of 0.8-1 mm thick HSLA and DP type high strength steel sheets. Joints were made using a Yb:YAG disc laser having a maximum power of 12 kW and a welding head by means of which it was possible to focus a laser beam on two spots, 0.6 mm and 1 mm away. The angle between focuses amounted to 0° or 90°, whereas the power distribution was 50%-50%. With settings as presented above it was possible to obtain high-quality overlap joints. The geometrical parameters of the joints were primarily affected by beams positions (in relation to each other) and, to a lesser degree, by the distance between the focuses. It was possible to obtain a 10% hardness reduction in the fusion zone of the DPHSLA steel joints if the angle between the beams amounted to 90°. The tests also involved microstructural examinations of individual zones of the joints
The Effect of Long-Term Impact of Elevated Temperature on Changes in Microstructure and Mechanical Properties of HR3C Steel
Authors: Zieliński A. , Sroka M. , Hernas A. , Kremzer M. 
Published: July 2016

Abstract
The HR3C is a new steel for pressure components used in the construction of boilers with supercritical working parameters. In the HR3C steel, due to adding Nb and N, the compounds such as MX, CrNbN and M23C6 precipitate during service at elevated temperature, resulting in changes in mechanical properties. This paper presents the results of microstructure investigations after ageing at 650, 700 and 750 °C for 5,000 h. The microstructure investigations were carried out using scanning and transmission electron microscopy. The qualitative and quantitative identification of the existing precipitates was carried out using X-ray analysis of phase composition. The effect elevated temperature on microstructure and mechanical properties of the examined steel was described.
Corrosion of Biocompatible Mg66+xZn30-xCa4 (x=0.2) Bulk Metallic Glasses
Authors: Nowosielski R. , Cesarz-Andraczke K. , Sakiewicz P. , Maciej A. , Jakóbik-Kolon A. , Babilas R. 
Published: July 2016

Abstract
The aim of this paper was to investigate the corrosion resistance of Mg66Zn30Ca4 and Mg68Zn28Ca4 metallic glasses and evaluate the ability of this amorphous alloy use for medical applications as biodegradable medical implants. Taking into account the amount of Mg, Zn, Ca elements dissolved in multielectrolyte physiological fluid (MPF) from Mg66+xZn30-xCa4 (x=0.2) alloys the daily dose of evolved ions from alloys components was determined. Additional goal of the paper was determination of corrosion rate (Vcorr) and amount of hydrogen evolved from amorphous magnesium alloys in simulated environment of human body fluids during 24h immersion and during electrochemical tests. Corrosion studies were done in the multielectrolyte physiological fluid (MPF) at 37°C. The amount of hydrogen evolved [ml/cm2] and corrosion rate Vcorr [mm/year] of amorphous Mg66Zn30Ca4 and Mg68Zn28Ca4 alloys were compared. The work also presents characterization of Mg-based bulk metallic glasses structure in the form of 2 mm thickness plates. Samples structure was analyzed by means of X-ray diffraction. Fracture and surface morphology of magnesium alloy samples were identified using scanning electron microscopy.