bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimization of Wear Parameters Considering Specific Energy Equivalence during Two-body Abrasion of ‘EPDM’ Rubber
Authors: Mukhopadhyay Abhijit 
Published: March 2014

AbstractWith several renewed and advanced researches in the recent past rubber, a viscoelastic material, emerges as a very suitable and important material for various engineering and other applications. EPDM rubber, one of the dominant elastomer, has a major application as seal in automobile doors, windows and other parts along with different other uses. Rubbers, in general have good abrasion resistance. But abrasion will lead to the impairment of the desired function of the components. Thus, the evaluation of abrasion, whatever small may be, is important.In the present work mere mass loss has not been considered as a measure of abrasion. On the contrary, an ideal function, specific energy has been modeled utilizing the concept of grinding operation. Abrasion has been interpreted in terms of specific energy. The modeled ideal function can be interpreted in two different ways. If abrasion, that is, mass loss is to be minimized then the specific energy of the material should have maximum value. Otherwise, from energy perspective, if the energy is to be minimized then more material must have to be removed in a single pass thus maximizing the mass loss. However, in the present work the objective is to understand the operating conditions which will give minimum loss of EPDM rubber when abrasion takes place. This theoretical study is a part of characterization of EPDM rubber from tribological point of view and primarily based on controlled laboratory experimentation conditions. It is need less to be mentioned that in real life applications the noise factors, as have been selected for the study, are beyond control in that sense and thus abrasion of EPDM can't be predicted through this model. However, in case of automated door and window locking system of automobiles, metros etc. this model will have some meaningful application potential.
A Review on Hard Turning by using Design of Experiments
Authors: Bhemuni V.P. , Chalamalasetti S.R. 
Published: March 2014

AbstractHard turning is the process of machining hardened steels that are above 45HRC. In manufacturing, hard turning has emerged as a potential area because of its many advantages over grinding as a finishing operation. In the present paper, a review is done on Design of Experiment (DOE) techniques that have been employed on various hard turning processes by researchers. DOE is one of the widely used methods for experimental study of many manufacturing processes in engineering. It is a statistical approach in which a mathematical model is developed through a minimum of experimental runs. DOE predicts the possible output, based on the given input parameters in an experiment. The present study predominantly focuses on the usage of Response Surface Method, Taguchi’s method and Factorial method in hard turning.
Synthesis of Uniform and High Density Silver Nanoparticles by using Peltophorum pterocarpum flower Extract
Authors: BALAMURUGAN Matheswaran , SARAVANAN Shanmugam , OHTANI Naoki 
Published: March 2014

ABSTRACTSilver nanoparticle (AgNP) is one of the elegant material because its uses in various fields. In this study, AgNPs have been prepared by using Peltophorum pterocarpum (PP) flower extract as reducing and capping agent and aqueous silver nitrate (aq.AgNO3) as silver precursor. The synthesized nanoparticles were characterized using Ultra Violet - Visible (UV-Vis) spectroscopy, High Resolution Transmission Electron Microscope (HR-TEM) and Fourier Transform Infrared Spectroscopy (FT-IR), which reveals the formation of nanosized particles. The UV-Vis spectrum shows an absorption peak around 430nm. HR-TEM images of AgNPs with clear morphology and well dispersed prepared AgNPs.
Fabrication of Organic Thin Film Transistor Arrays on Plastic and Paper Substrate for Flexible Display Application
Authors: Fujisaki Y. , Nakajima Y. , Nakata M. , Tsuji H. , Yamamoto T. 
Published: March 2014

ABSTRACTOrganic thin-film transistors (OTFTs) are the most promising candidates for flexible electronics owing to their flexible structures, the simplicity of processing large-area devices, and excellent compatibility with flexible substrates. To date, many studies have been reported that have aimed at developing a wide range of plastic electronics such as flexible displays, sensors. In this paper, we discuss our recent work, focusing on OTFT arrays and their application to flexible display. An active-matrix (AM) backplane using a low-temperature cross-linkable olefin-type polymer as the gatedielectric and an air-stable DNTT as the organic semiconductor (OSC) was successfully fabricated on a plastic substrate. The short-channel TFT array exhibited a high hole mobility of over 0.5 cm2/Vs, a low subthreshold slope of 0.31, and excellent environmental and operational stability. A 5-inch flexible OLED display exhibited a high luminescence of over 300 cd/m2 by driving of the DNTT-based OTFTs. Solution-processed OTFTs are also attracting considerable attention owing to both their simple manufacturing process and excellent transistor performance. We present a simple patterning process for a solution-processable OSC that can be used to develop a high-mobility short-channel TFT array. The OSC film was directly patterned on the confined active channel region by a simple lamination coating technique and the resulting TFTs showed a high mobility of up to 1.3 cm2/Vs. In the final section, we report on eco-friendly paper-based organic TFT array. A transparent cellulose nanofibers paper was firstly applied to a flexible substrate for the TFT backplane. A solution-processed TFT on the transparent paper exhibited a high mobility exceeding 1 cm2/Vs, good air stability, and excellent mechanical stability.
Mesoporous Au–TiO2 Nanoparticle Assemblies as Efficient Catalysts for the Chemoselective Reduction of Nitro Compounds
Authors: Tamiolakis Ioannis , Lykakis Ioannis N. , Armatas Gerasimos S. 
Published: March 2014

ABSTRACTHere, we propose novel mesoporous Au-loaded TiO2 nanoparticle assemblies (Au-MTA) as highly effective catalysts for the reduction of nitroaromatic compounds into the corresponding aryl amine products. The obtained materials possess a continuous network of interconnected gold and anatase TiO2 (ca. 9 nm in size) nanoparticles with controllable gold particle size (i.e. ranging from ∼3.2 to ∼9.4 nm) and exhibit large and accessible pore surface area (ca. 100–160 m2/g), as evidenced by SAXS, XRD, TEM and N2 physisorption measurements. Interestingly, the Au-MTA mesophases have exhibited remarkable activity and selectivity for the reduction of nitro into amine groups using NaBH4 as reducing agent. Indeed, the Au loading and particle size have a key effect on hydrogenation reactions, affecting significantly the yield and product composition.
Au-Rh and Au-Pd Nanoalloys supported on well-defined Rutile Titania Nanorods for Aromatics Hydrogenation Applications
Authors: Konuspayeva Zere , Berhault Gilles , Afanasiev Pavel , Nguyen Thanh-Son , Auyezov Ali , Burkitbayev Mukhambetkali , Piccolo Laurent 
Published: March 2014

ABSTRACTTiO2-supported bimetallic Au-Rh and Au-Pd nanocrystals were synthesized using both impregnation and colloidal approaches employing HAuCl4 and RhCl3 as precursors. The as-obtained bimetallic catalysts were then supported onto TiO2 rutile nanorods in order to provide catalytic systems with well-defined metal-support interactions for HRTEM characterization. The results revealed the superiority of the colloidal approach over the impregnation technique to obtain bimetallic nanoparticles (4 nm in size) with tunable composition. However, for Au-Rh/TiO2, optimization of the procedure of the sol immobilization onto the TiO2 support was required to avoid possible Rh re-dissolution. Preparation of Au-Pd/TiO2 followed the same procedure but with more acidic conditions necessary to perform immobilization on the support. UV-vis spectroscopy and XRD results suggest formation of a Rh-rich shell over an Au core center for Au-Rh NPs, while Au-Pd NPs present a pure alloy structure. Au-Rh/TiO2 was used for performing the high-pressure hydroconversion of tetralin in the presence or not of H2S. The results indicate a strong thioresistance induced by the addition of Au to Rh.
Genome-wide Chromatin Mapping Defines AP2α in the Etiology of Craniofacial Disorders
Authors: Enkhmandakh Badam , Bayarsaihan Dashzeveg 
Published: March 2014

Objective The aim of this study is to identify direct AP2α target genes implicated in craniofacial morphogenesis. Design AP2α, a product of the TFAP2A gene, is a master regulator of neural crest differentiation and development. AP2α is expressed in ectoderm and in migrating cranial neural crest (NC) cells that provide patterning information during orofacial development and generate most of the skull bones and the cranial ganglia. Mutations in TFAP2A cause branchio-oculofacial syndrome characterized by dysmorphic facial features including cleft or pseudocleft lip/palate. We hypothesize that AP2α primes a distinctive group of genes associated with NC development. Human promoter ChIP-chip arrays were used to define chromatin regions bound by AP2α in neural crest progenitors differentiated from human embryonic stem cells. Results High-confidence AP2α-binding peaks were detected in the regulatory regions of many target genes involved in the development of facial tissues including MSX1, IRF6, TBX22, and MAFB. In addition, we uncovered multiple single-nucleotide polymorphisms (SNPs) disrupting a conserved AP2α consensus sequence. Conclusions Knowledge of noncoding SNPs in the genomic loci occupied by AP2α provides an insight into the regulatory mechanisms underlying craniofacial development.
Evaluation of Premature Membrane Exposure and Early Healing in Guided Bone Regeneration of Peri‐Implant Dehiscence and Fenestration Defects With a Slowly Resorbing Porcine Collagen Ribose Cross‐Linked Membrane: A Consecutive Case Series
Authors: Scheyer E. Todd , McGuire Michael K. 
Published: March 2014

Introduction: Guided bone regeneration (GBR) is a well‐known and accepted procedure for effective treatment of oral bony defects that is dependent on sustained barrier membrane function for adequate new bone formation. Cross‐linking between collagen fibrils with various agents has proven to be effective in prolonging membrane integrity and function, both critical to positive bone regenerative outcomes. Overlying mucosal dehiscence with membrane exposure may lead to less than adequate new bone formation. The current case series examines guided bone regenerative outcomes for peri‐implant defects using a ribose cross‐linked porcine collagen membrane that appears to reduce the risk of cross‐linking–associated membrane exposure.Case Series: Seven patients with nine sites having peri‐implant dehiscence and fenestration defects were enrolled in this consecutive case series pilot study. At surgery, the linear range of implant thread exposure was 5 to 10 mm (mean of ≈6.3 mm). After implant insertion, grafting with mineralized allograft, and placement of a ribose cross‐linked collagen membrane, patients were followed for a minimum of 6 months. At 6‐month reentry surgery, all dehiscence and fenestration defects were eliminated with newly regenerated bone covering previously exposed implant threads. No membrane exposure occurred during this study.Conclusions: Successful GBR outcomes may be enhanced by avoiding premature membrane exposure. Although collagen cross‐linking may be associated with increased mucosal dehiscence, the ribose cross‐linked membrane examined in the current study may help promote positive regenerative outcomes by sustained functional and structural integrity and a reduction in membrane exposure incidence.
Head and Neck Squamous Cell Carcinoma: Prognosis using molecular approach
Authors: Mazumder Tarikul , Nath Sayantan , Nath Nibendu , Kumar Munish 
Published: March 2014

Abstract
Head and neck squamous cell carcinoma (HNSCC) is the fifth most prevalent cancer worldwide. Apart from various known clinicopathogical factors, it is still a major concern as many genetic and epigenetic alterations bring about the possibility of this deadly disease. The aim of this review is to explore the possible role of DNA repair pathways and the polymorphic status of DNA repair genes (XPA, XPC, XPD, XRCC1 and XRCC3) in the onset of HNSCC, along with sequence variations in genes such as Glutathione S-transferases (GSTT1, M1 and P1) that are significantly associated with HNSCC risk. We also focus on the p53 gene mutation induced by various etiological agents and threat factors with its implications towards HNSCC, and emphasise the current therapeutic interventions in treating HNSCC.
Combined pharmacological therapy of the acute radiation disease using a cyclooxygenase-2 inhibitor and an adenosine A3 receptor agonist
Authors: Hofer Michal , Pospíšil Milan , Dušek Ladislav , Hoferová Zuzana , Komůrková Denisa 
Published: March 2014

Abstract
Combined approaches to the treatment of acute radiation disease are preferred to single-agent therapies due to proven or anticipated better outcomes comprising increased therapeutic efficacy and decreased incidence of undesirable side effects. Our studies on post-exposure treatment of mice irradiated by sublethal or lethal doses of ionizing radiation included testing the effectiveness of meloxicam, a cyclooxygenase-2 inhibitor, and IB-MECA, an adenosine A3 receptor agonist. The efficacy of meloxicam and IB-MECA to positively influence the progress of the acute radiation disease has been tested in situations of their combined administration with granulocyte colony-stimulating factor (G-CSF) or with each other. The results of our studies revealed a significantly improved regeneration of hematopoietic cell populations ranging from the bone marrow progenitor cells to mature blood cells following combined treatments. Also, survival of mice exposed to lethal radiation doses was highest in the animals treated with a combination of the two drugs. It can be inferred from the results that if the drug combinations employed were used in humans, e.g. in the treatment of victims of radiation accidents, a better therapeutic outcome could be expected. Therefore, further studies directed at clinical applications of meloxicam and IB-MECA in radiation victims is recommended.
Biological properties of novel chitosan-based composites for medical application as bone substitute
Authors: Przekora Agata , Ginalska Grażyna 
Published: March 2014

Abstract
Hydroxyapatite is the main inorganic component of bones and teeth. In order to improve mechanical properties and surgical handiness of bioceramics, a plasticizing agent e.g. polysaccharide can be added. Chitosan is a polysaccharide with biological properties that make it an ideal component of bioceramics-based composites for medical application as bone substitute. In this study, biocompatibility of two types of novel krill chitosan-based composites was evaluated. In vitro experiments were carried out using human foetal osteoblast cell line. Cytotoxicity, cell adhesion, and bone ALP activity tests were performed to assess biocompatibility of the composites. Osteoblast growth on composites was observed using confocal microscope. Our results demonstrated that fabricated novel composites are non-toxic, are favorable to cell adhesion and growth, and provoke increase in b-ALP activity with time, thus inducing osteoblast differentiation. Based on this data composites have promising clinical potential as a bone defect filler in regenerative medicine. It is worth emphasizing that our work resulted in fabrication of flexible and surgical handy, bone substitutes that possess absolute biocompatibility with structural and mechanical properties similar to trabecular bone.
Thermal resistance of GaAs/AlAs superlattices used in modern light-emitting diodes
Authors: Żak D. , Nakwaski W. 
Published: March 2014

AbstractSuperlattices are used in modern light-emitting diodes to modify intentionally electron, phonon and/or photon transport within their volumes, which leads to their expected performance characteristics. In particular, superlattices may have a dramatic impact on device thermal properties. Superlattice thermal resistance is anisotropic and usually distinctly higher than its values in constituent bulk materials, which results from phonon reflections and/or phonon scatterings at numerous layer interfaces. In the present paper, thermal resistance of a typical superlattice of layer thicknesses neither much higher nor much lower than the phonon free path is discussed. Besides, as an important example, thermal resistance of the typical GaAs/AlAs superlattice is determined theoretically and compared with its measured values known from literature.
Intracavity polarization control in mode-locked Er-doped fibre lasers using liquid crystals
Authors: Nikodem M. , Krzempek K. , Zygadlo K. , Dudzik G. , Waz A. , Abramski K. , Komorowska K. 
Published: March 2014

AbstractIn this paper we present a novel configuration of an NPR mode-locked Er-doped laser. This new optical setup uses voltage controlled LC cells to replace standard retarders (quarter-and half-waveplates) inside the laser cavity. Using this novel, mechanical-adjustment-free setup a mode-locking was obtained with sub-500 fs pulse duration and an average power exceeding 40 mW. Presented results show that using simple LC cells, an optical layout of an NPR mode-locked laser can be greatly simplified.
Compositional arrangement of rod/shell nanoparticles: an approach to provide efficient plasmon waveguides
Authors: Ahmadivand A. , Golmohammadi S. 
Published: March 2014

AbstractIn this work, we investigated the optical properties of a novel compositional configuration of gold nanorod and silver nanoshell which is embedded in a SiO2 substance. The proper geometrical sizes for compositional rod/shell arrangement have been obtained based on the position and peak of plasmon resonance at λ ∼1550 nm. Adjusting the plasmon resonance position at declared spectrum helps us to provide an arrangement which shows high efficiency and minimum losses. The influence of destructive components such as internal damping and scattering on the rod/shell combination is demonstrated by corresponding diagrams. Moreover, we proposed a nano-array based on examined configuration and the quality of light transmission along the array is studied. We figured out and depicted optical properties of the array such as transmission loss factors, group velocities, transmitted power, transmission quality, and two-dimensional snapshots of surface plasmons (SPs) coupling between nanoparticles arrangements under transverse and longitudinal modes excitations. Ultimately, it is shown that the suggested nanostructure based on studied nanoparticles configuration has a potential to utilize in designing nanophotonic devices such as splitters, couplers, and routers. Finite-difference time-domain method (FDTD) as a major simulation model has been employed to study the features of the waveguide.
Study of the effect of director fluctuations on liquid-crystalline molecular reorientation
Authors: Sierakowski M. , Woliński T. , Orzechowski K. 
Published: March 2014

AbstractInitial phase of field-induced molecular reorientation in threshold geometry of a liquid-crystalline structure is essentially influenced by thermal orientational fluctuations. Still not quite clear is the way in which the reorientation starts and how it runs over an LC-structure in its initial phase. Fluctuations are stochastic events in time and also in space. This feature suggests, that the reorientation process may be induced by director fluctuations locally in a particular part of the LC-structure. In this work we have studied the impact of fluctuations on the molecular reorientation in nematics involving optical nonlinear interaction. The restricted area of a nematic layer was excited by light beam that amplified director fluctuations locally. By manipulation of optical excitation we were able to affect the dynamics of the effect. Since the threshold-type configuration of nematics is used in a number of optical devices, the obtained results may have practical aspect contributing to a new way of controlling the field-induced transition.
Development of biomimetic gelatin–chitosan/hydroxyapatite nanocomposite via double diffusion method for biomedical applications
Authors: Raz Majid , Moztarzadeh Fathollah , Shokrgozar Mohammad A. , Azami Mahmoud , Tahriri Mohammadreza 
Published: March 2014

Abstract
In this research, nanocomposite scaffolds were prepared from gelatin/chitosan and hydroxyapatite via a biomimetic method. The prepared scaffolds were then evaluated by means of commonly used bulk techniques: X-ray diffraction, scanning electron microscopy and Fourier transform infra-red spectroscopy. In this study, the gelatin–chitosan/apatite nanocomposite scaffolds were fabricated using the applied biomimetic method accompanied by freeze drying. The apatite was formed using double diffusion within the gelatin/chitosan hydrogel at similar pH and temperature to the human body. The obtained nanocomposites were soaked in glutaraldehyde solution in order to enhance their mechanical properties and also make them insoluble in water. Diffusion of calcium and phosphate ions from lateral sides into the hydrogel middle caused formation of a white layered precipitate. Analysis of precipitates formed within the hydrogel middle for the samples showed that detected materials are composed of carbonated hydroxyapatite and amorphous dicalcium phosphate dihydrate. After incubation in simulated body fluid, the amorphous phase converted to crystalline hydroxyapatite, which process is similar to bone formation in the human body. Mechanical properties obtained for the scaffolds were comparable to spongy bone. Also in this work, MTT assay and alkaline phosphatase activity on the prepared scaffolds were evaluated and discussed. Finally, the obtained experimental results ascertained that the nanocomposite prepared with chitosan/gelatin (20/80) had appropriate properties for bone tissue engineering scaffold.
Classical controlled rolling of low C steels microalloyed with Ti and Mo
Authors: Calvo Jessica , Collins Laurie , Yue Stephen 
Published: March 2014

Abstract
Two low-C steels, one microalloyed with Ti and the other with Ti and Mo were subjected to a classical controlled rolling schedule using torsion testing. The specific torsion schedules were a simulation of an industrial schedule adapted to the characteristic transformation temperatures of each steel. It is shown that such steels can develop a pancaked austenite, despite the fact that the alloys do not contain Nb. However, compared to Nb bearing steels, restoration between deformation passes is relatively rapid in the pancaking region. In order to reduce the loss of pancaking, the temperatures of the finishing rolling schedule were shifted to lower temperatures. This appeared to greatly reduce the restoration rates, but the transformation in the two phase region occurred towards the end of the final deformation pass. When comparing the two steels, it could be detected that Mo increases the temperature range for pancaking and reduces the restoration rates between deformation passes in the pancaking region.