bluuebunny/crossref_metadata_2025_split huggingface dataset:
AN ENZYMATIC METHOD TO OBTAIN A NEW SCAFFOLD FOR ENGINEERING CARTILAGE
Authors: Giraldo Gomez David M. , Villegas Alvarez Fernando , Garciadiego Cazares David , Sotres Vega Avelina , Piña Barba Maria C. 
Published: March 2013

ABSTRACTThe purpose of this study was to achieve a descellularized scaffold from cartilage tissue, which can be used as xenograft for cartilage tissue regeneration.This work presents the results obtained using one method to wash porcine trachea in order to remove cellular material from the extracellular matrix and to avoid the immune reaction using enzymatic detergent and partial enzymatic degradation with Deoxyribonuclease I (DNase-I), Ethylenediaminetetraacetic Acid (EDTA) and Trypsin. This treatment was qualitatively evaluated by Scanning Electron Microscopy (SEM), and H&E Stain (Histology), and quantitatively evaluated by DNA quantification. The thermal characterization of the descellularized scaffold was carried out using Termogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The type of collagen obtained from the scaffold was determined through SDS-PAGE electrophoresis. When using Enzymatic Treatment (ET) to wash trachea tissue, it is possible to obtain an acellular xenograft; this procedure has the potential to avoid rejection reactions of the xenograft.
Decontamination of Molten Salt Wastes for Pyrochemical Reprocessing of Nuclear Fuels
Authors: Stennett Martin C. , Hand Matthew L. , Hyatt Neil C. 
Published: March 2013

ABSTRACTPyrochemical reprocessing of nuclear fuels, in which electrochemical separation of actinides and fission products is mediated by a molten alkali chloride salt (typically a LiCl-KCl eutectic) is of interest for future nuclear energy cycles. A key challenge in the management of pyrochemical reprocessing wastes is decontamination and recycling of the molten salt medium to remove entrained actinides and radioactive lanthanide fission products. Since pyrochlore oxides are promising candidates for the immobilisation of lanthanides and actinides, we sought to use the “problematic” molten salt to our advantage as a reaction medium for low temperature synthesis of titanate pyrochlores. Through control of reaction time and temperature, we demonstrated the synthesis of lanthanide pyrochlores at temperatures as low as 700 °C in 1 h, compared to 1350 °C in 36 h for conventional solid state synthesis. The importance of this study is in demonstrating the potential feasibility for decontamination of pyrochemical reprocessing wastes by simple addition of TiO2 to form lanthanide and actinide pyrochlores by rapid molten salt assisted reaction at moderate temperature.
Sperm Performance Better on Diamond than on Polystyrene
Authors: Sommer Andrei P. , Zhu Dan , Gagsteiger Friedrich , Fecht Hans-Jörg 
Published: March 2013

ABSTRACTRecently we postulated that polystyrene Petri dishes become soft when in contact with an aqueous milieu. Specifically, we assumed that the effect is restricted to a superficial nanolayer, a condition presumably favoring the establishment of a stable nanolayer of reactive oxygen species (ROS) at the liquid/solid-interface. Cells are known to be hypersensitive to ROS. Previously we used P19 mouse embryonal carcinoma cells and systematically analyzed their capability to climb different substrates placed vertically into a Petri dish. The worst and best performance was found on polystyrene (Petri dish material) and nanocrystalline diamond, respectively. Polystyrene Petri dishes are today standard in laboratories conducting in vitro fertilization (IVF). Here we proceed and extend the investigation to human spermatozoa and show that their performance (vitality) on polystyrene Petri dishes is low compared to that on diamond Petri dishes. This work may propel further research and inspire the development of a new generation of cell-friendly Petri dishes.
Comparison of multi-crystalline silicon PV modules’ performance under augmented solar irradiation
Authors: Hu Yang , Hollingshead Dave , Hossain Mohammad A. , Schuetz Mark , French Roger 
Published: March 2013

ABSTRACTIn developing photovoltaic (PV) systems with reliable lifetime performances, it is critical to have quantitative knowledge of not just initial properties and performances, but also their performance over the warrantied 25 year lifetime. In 2010, the Science for Energy Technology Workshop, convened by U.S Department of Energy (DOE) Basic Energy Science, prioritized photovoltaic module lifetime and degradation science (L&DS), which serve as the basis for quantitative and mechanistic understanding of lifetime performance. In order to better understand degradation rates and mechanisms of PV systems in the real-world environment, the SDLE SunFarm at Case Western Reserve University has been created, which is a highly instrumented outdoor test facility with 148 PV modules and > 8000 samples on sun for weathering and degradation studies of materials components and systems designed for long-lived energy systems. I-V and power performance of 10 multi-crystalline silicon PV modules from different manufacturers, using baseline and continuous power monitoring and comprehensive weather and solar resource monitoring, to enable time series analysis for insights into performance characteristics and initial degradation.Five modules from each manufacturer were exposed using mirror augmentation in typical (Cleveland, OH) climatic conditions. The mirror augmentation used geometric concentration factors of 1X, 1.5X and 1.9X of the nominal 1 sun. The effect of mirror augmentation on the modules' performance is reported. A Daystar multi-tracer was used to measure I-V curves of individual modules every 15 minutes while power output under maximum power point tracking was monitored continuously. Monitoring environmental factors (wind speed, wind direction, rainfall, and humidity), solar resource, and module temperatures allow for determination of the effects of these conditions on module power production. Power data was corrected to standard test condition (STC) according to climatic and solar irradiance. Changes in fill factor, short circuit current, open circuit voltage and maximum power are reported for each module. With time series analysis, a better understanding of the module's performance over time and under environmental conditions can be developed.
Transparent Platinum Counter Electrode for Building Integrated Dye-Sensitized Solar Cells
Authors: Iefanova Anastasiia , Baroughi Mahdi Farrokh , Davoux Daren , Gautam Umesh , Dachhepati Dilip , Nepal Jeevan 
Published: March 2013

ABSTRACTA new type of counter-electrode based on platinum (Pt) nanoclusters has been introduced for semi-transparent dye-sensitized solar cells (DSSCs). This electrode is fabricated using a drop coating method where Pt nanoparticles dispersed in an acetone solvent are applied on a heated indium tin oxide (ITO) coated glass substrate. Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM) images suggest that the Pt nanoparticles form a nanoporous structure with a large surface area while the distribution of Pt appears to be uniform on the surface of the ITO layer. UV/visible/near infrared transmittance spectroscopy showed that the Pt/ITO/glass electrode is highly transparent with a maximum transparency of 80% at 550 nm.
Laser Scribing of W-textured ZnO Substrates Using Green Laser
Authors: Ishikawa Ryousuke , Wada Hidetoshi , Kurokawa Yasuyoshi , Sichanugrist Porponth , Konagai Makoto 
Published: March 2013

ABSTRACTThin-film silicon solar cells have been attracted a lot of intention as low-cost solar cells. One of the most important technologies for improving their performances is light trapping. We have demonstrated the high potential of double-textured zinc oxide (ZnO) thin films used as front transparent conductive oxide (TCO) films due to further enhancement of their light-trapping effects. Although the laser scribing method has already been well established for low-cost thin-film silicon solar cell module manufacturing, laser scribing technique on double-textured ZnO is new and still a challenging issue. In this study, we firstly demonstrated the availability of laser scribing for amorphous silicon (a-Si) solar cells fabricated on double-textured ZnO substrates. It is general to utilize lasers with wavelength of 1.06 μm and 532 nm for scribing of TCO and silicon layer, respectively. Here we attempted to scribe both of TCO and silicon layers using a 532 nm wavelength laser (green laser) for process simplifying.
Growth of SnS van der Waals Epitaxies on Layered Substrates
Authors: Wang S.F. , Fong W.K. , Wang W. , Leung K.K. , Surya C. 
Published: March 2013

ABSTRACTIn this paper we present systematic investigations on the growth of SnS van der Waals epitaxies (vdWEs) on different substrates, including crystalline and layered substrates, by molecular beam epitaxy (MBE). Experimental growth of SnS on conventional 3D substrates, such as GaAs, indicates strong interaction between the SnS layer and the substrate resulting in poor crystallinity in general. Substantial improvement in the film crystallinity can be obtained when the deposition is made on layered substrates, with saturated surface bonds, as observed in SnS films deposited on mica and crystalline substrates with a graphene buffer layer. Crystal size as large as one micron and rocking curve FWHM of 0.118° was observed despite the large lattice mismatches. This represents significant improvement over the reported value of ∼3°. Several symmetric growth orientations are observed for films grown on mica substrates. The results indicate that weak vdW interactions between the saturated bonds of the substrate surface and the SnS unit layer which is an important factor for achieving high quality epitaxy layered materials.
Simulating Constant Current STM Images of the Rutile TiO2 (110) Surface for Applications in Solar Water Splitting
Authors: Sanches F. F. , Mallia G. , Harrison N. M. 
Published: March 2013

ABSTRACTSolar water splitting has shown promise as a source of environmentally friendly hydrogen fuel. Understanding the interactions between semiconductor surfaces and water is essential to improve conversion efficiencies of water splitting systems. TiO2 has been widely adopted as a reference material and rutile surfaces have been studied experimentally and theoretically. Scanning Tunneling Microscopy (STM) is commonly used to study surfaces, as it probes the atomic and electronic structure of the surface layer. A systematic and transferable method to simulate constant current STM images using local atomic basis set methods is reported. This consists of adding more diffuse p and d functions to the basis sets of surface O and Ti atoms, in order to describe the long range tails of the conduction and valence bands (and, thus, the vacuum above the surface). The rutile TiO2 (110) surface is considered as a case study.
Room Temperature Ferromagnetism and Band Gap Investigations in Mg Doped ZnO RF/DC Sputtered Films
Authors: Mahadeva Sreekanth K. , Quan Zhi-Yong , Fan J. C. , Albargi Hasan B , Gehring Gillian A , Riazanova Anastasia , Belova L. , Rao K. V. 
Published: March 2013

ABSTRACTMg@ZnO thin films were prepared by DC/RF magnetron co-sputtering in (N2+O2) ambient conditions using metallic Mg and Zn targets. We present a comprehensive study of the effects of film thickness, variation of O2 content in the working gas and annealing temperature on the structural, optical and magnetic properties. The band gap energy of the films is found to increase from 4.1 to 4.24 eV with the increase of O2 partial pressures from 5 to 20 % in the working gas. The films are found to be ferromagnetic at room temperature and the saturation magnetization increases initially with the film’s thickness reaching a maximum value of 14.6 emu/cm3 and then decreases to finally become diamagnetic beyond 95 nm thickness. Intrinsic strain seems to play an important role in the observed structural and magnetic properties of the Mg@ZnO films. On annealing, the as-obtained ‘mostly amorphous’ films in the temperature range 600 to 800°C become more crystalline and consequently the saturation magnetization values reduce.
Vitrification of high molybdenum feeds in the presence of reprocessing waste liquor
Authors: Short Rick , Dunnett Barbara , Gribble Nick , Steel Hannah , Steele Carl James 
Published: March 2013

ABSTRACTAt Sellafield, the Post Operational Clean Out (POCO) of solids from the base of the highly active waste storage tanks, in preparation for decommissioning, will result in a high molybdenum stream which will be vitrified using the current Waste Vitrification Plant (WVP). In order to minimise the number of containers required for POCO, the high molybdenum feed could be co-vitrified by addition to reprocessing waste, using the borosilicate glass formulation currently utilised on WVP. Co-vitrification of high molybdenum feeds has been carried out using non-active simulants, both in the laboratory and on the Vitrification Test Rig (VTR) which is a full scale working replica of a WVP processing line.In addition, a new borosilicate glass formulation containing calcium has been developed by NNL which allows a higher incorporation of molybdenum through the formation of a durable CaMoO4 phase, after the solubility limit of molybdenum in the glass has been reached. Vitrification of the high molybdenum feed in the presence of varying quantities of reprocessing waste liquor using the new glass formulation has been carried out in the laboratory. Up to ∼10 wt% MoO3 could be incorporated without any detrimental phase separation in the product glass, but increasing the fraction of reprocessing waste was found to decrease the MoO3 incorporation. Soxhlet and static powder leach tests have been performed to assess the durability of the glass products. This paper discusses the results of the vitrification of high molybdenum feeds in the presence of reprocessing liquor in both the borosilicate glass formulation currently utilised on WVP and the modified formulation which contain calcium.
Comparative Raman and Transmission Electron Microscopy Analysis of the Evolution of Platelet Defects in Plasma Hydrogenated and Annealed Czochralski Silicon
Authors: Job R. , Beaufort M.-F. , Barbot J.-F. , Ulyashin A. G. , Fahrner W. R. 
Published: March 2013

AbstractStandard p- and n-type Czochralski (Cz) silicon wafers were hydrogenated by a RF (13.56 MHz) hydrogen plasma at moderate temperatures (250 °C). After plasma hydrogenation and subsequent annealing up to 600 °C the formation and of H2 molecules in voids and platelets was investigated by Raman spectroscopy. The Raman intensities of the H2 vibration modes at ∼ 4150 cm-1 exhibited significant intensity modulations in dependence on the annealing temperature. The intensities of the H2 Raman lines indirectly monitor the evolution of the voids and platelets upon annealing. This assumption was verified by cross-sectional transmission electron microscopy (XTEM), which was applied for comparison. The intensity modulations of the H2 Raman signal can be explained by the evolution of the well known {111} and {001} platelets. At lower annealing temperatures (< 500 °C) platelets laying in {111} planes are dominant, while at elevated temperatures (> 500 °C) [001]-oriented platelets become more and more important. In addition in p-type material by XTEM also {110} platelets could be observed.
Partial annealing of defects in boron-implanted p-type silicon by hydrogen implantation
Authors: Tokuda Yutaka , Iwata Hiroyuki 
Published: March 2013

AbstractHydrogen implantation has been used to anneal defects produced in p-type silicon by boron implantation. Boron implantation is performed with an energy of 300 keV to a dose of 1×109 cm-2. Deep level transient spectroscopy measurements show the production of four hole traps (Ev + 0.21, 0.35, 0.50, 0.55 eV) by boron implantation. Subsequent hydrogen implantation is performed with energies of 60, 90, 120 and 150 keV to a dose of 2×1010 cm-2. Among four traps produced by boron implantation, the most significant effect of hydrogen implantation is observed on one trap (Ev + 0.50 eV). A 62% decrease in concentration is caused for this trap by hydrogen implantation with energies of 120 and 150 keV. This partial annealing is ascribed to the reaction of boron-implantation-induced defects with point defects produced by hydrogen implantation.
Doping of Oxidized Float Zone Silicon by Thermal Donors - a Low Thermal Budget Doping Method for Device Applications?
Authors: Job R. , Ulyashin A.G. , Huang Y.L. , Fahrner W.R. , Simoen E. , Claeys C. , Niedernostheide F.-J. , Schulze H.-J. , Tonelli G. 
Published: March 2013

AbstractThermal donor formation was studied in oxygen enriched high resistive float zone silicon (FZ Si:Oi). Such substrates are used e.g. for radiation hard detectors or high voltage devices. RF Plasma hydrogenation (110 MHz, 50 W) was carried out at 250°C for 1 hour. Subsequent annealing was done at 450°C/air for up to 50 h. The plasma treated and annealed FZ Si:Oi samples were analyzed by spreading resistance probe, capacitance-voltage and DLTS measurements. It is shown that a rapid formation of donors can be observed in oxidized FZ Si:Oi, but in a somewhat different way than in Czochralski (Cz) Si. While in Cz Si the hydrogen enhanced formation of ‘old’ thermal double donors occurs under the applied processes, in FZ Si:Oi most probably the formation of new hydrogen related shallow donors can be assumed.
Design Evolution of Drilling Tools to Mitigate Vibrations
Authors: Bailey J. R. , Elsborg C. C. , James R. W. , Pastusek P. E. , Prim M. T. , Watson W. W. 
Published: March 2013

Abstract
The development of methods to characterize the relative vibration tendency of alternative bottomhole assemblies (BHA) has enabled deliberate tool redesign to reduce vibrations. To achieve the greatest benefit, tool redesign is most effective if applied early in the tool design cycle where important configuration parameters are most easily adjusted. This paper outlines several design issues that need to be resolved so the future generations of tools have inherently lower vibration levels.
The use of multiple special-purpose tools (such as logging tools, rotary steerable assemblies, and ream-while-drilling tools) generates significant constraints on BHA configuration options. A redesign methodology to achieve lower vibration indices can be used to investigate modified components, dimensions, and configurations to select the best BHA configuration for specific drilling operating conditions.
Case studies are used to investigate BHA designs with flex stabilizers above rotary steerable tools. The flex stabilizer comprises a stabilizer with a smaller diameter connecting flex sub to facilitate rotary steerable directional objectives. It is typically wired for tool signals and is frequently run by vendors. In another case study, the spacing below a reamer is evaluated and drilling data is compared to other assemblies in the same formation. In this example, the spacer provides an increase in the distance between contact points to allow both the stabilizer and reamer to seek the centerline with less interference. The fourth case study evaluates changing contact locations in the BHA by swapping the order of logging tools resulting in different borehole contact positions. Finally, a theoretical study illustrates how changing BHA components and dimensions affect the model vibration indices.
The operator has field experience with BHA redesign that has directly led to significant improvement in drilling performance. The benefits include higher rate of penetration (ROP), longer time on bottom, less wear of drilling tool components, and reduced frequency of trips.
The Combined Application of Azimuthal Deep Resistivity and Multi-Lateral Technologies Maximizes Extra-Heavy Oil Recovery and Improves Production Rates in Junin Block of the Orinoco Oil Belt
Authors: Palermo J. , Gutierrez R. , Ramos J. , Toledo O. , Garcia W. , Rondon L. , Cohen D. , Mendez O. 
Published: March 2013

Abstract
Petroleos de Venezuela, S.A. (PDVSA) Petrocedeno has encountered challenges in achieving higher production rates and maximizing extra-heavy oil recovery from complex reservoirs in the Junin block of the Orinoco oil belt of Venezuela. These complex reservoirs are located in heterolytic deltaic depositional environments, with heterolitic thicknesses ranging from 10 to 20 ft. This block produces 150,000 B/D from more than 700 horizontal wells. Most of these wells were drilled in relatively homogeneous sands with good thickness; however, large extra-heavy oil reserves are trapped in a more geologically and operationally complex deltaic reservoir sand. Horizontal wells in this area show poor production results.
For these reservoirs, the geosteering technique with azimuthal deep resistivity technology was proposed to maximize oil recovery by positioning the wellbore in a better pay-zone; advanced drainage multilateral architecture was proposed to improve production rates by increasing reservoir exposure. Multilateral technology has been used successfully in the area. Sand problems, observed in some multilateral wells, were solved by using a junction support tool to provide mechanical and hydraulic integrity at the junction area. A real-time geosteering technique enabled a flawless wellbore placement within this reservoir with challenging stratigraphy and complex sedimentological environment in which more than 60 wells have been drilled with azimuthal deep resistivity tools.
The well YC-36 well plan included drilling two laterals with the geosteering technique, which would improve the production rate to an estimated 343 B/D. After installing a multilateral level IV junction and positioning YC-36 100% in the net oil sand, the reported production increased to 650 B/D for an increase of approximately 300%, as compared to an average single well production from the block. This paper describes the combined application of multilateral and geosteering technologies in the YC-36 well and details about the results of the application.
Maximizing the Value of Real-Time Operations for Diagnostic and Optimization at the Right Time
Authors: Al-Jasmi A. , Goel H. K. , Al-Abbasi A. , Nasr H. , Velasquez G. , Carvajal G. A. , Cullick A. S. , Rodriguez J. A. , Scott M. 
Published: March 2013

Abstract
Although oilfield workflow automation processes have been implemented in the oil and gas industry during the last decade, the full impact and value of these technologies has yet to be realized. Tremendous potential still exists to implement new technology to maximize production, increase operational efficiency, and reduce down time/non-productive time. The Kuwait Integrated Digital Field project (KwIDF) is a novel intelligent digital oilfield operation for Kuwait Oil Company, the operator of the Sabriyah field in North Kuwait.
The project has successfully implemented improvements in field&#39;s operational efficiency by reducing the down time in artificial lift completion, increasing well productivity, and preventing water production. This paper provides an overview of the project from the perspective of field data acquisition, data analysis, model analysis, diagnostics, and operational optimization conducted in "right time" in the operator&apos;s state-of-the-art collaboration center.
The automated workflow system orchestrates integrated solutions that not only provide monitoring in real time, but also enable diagnostics and optimization for individual wells. The automated workflow integration and orchestration conducted by the production team within a collaborative work environment covers the following aspects described in this paper: production surveillance (including alarming and alert events), well performance, production losses, artificial lift optimization, and key performance monitoring.