bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Pozzolanic Reaction of Silica Fume
Authors: Jensen Ole M. 
Published: November 2012

ABSTRACTSilica fume is a very important supplementary cementitious binder in High-Performance and Ultra High-Performance Concretes. Through its pozzolanic reaction the silica fume densifies the concrete micro-structure, in particular it strengthens the paste-aggregate interfacial transition zone. In the present paper different aspects of the pozzolanic reaction of silica fume are investigated. These include chemical shrinkage, isothermal heat development and strength development. Key data for these are given and compared with theoretical calculations, and based on presented measurements the energy of activation of the pozzolanic reaction of silica fume is estimated. The results show that the pozzolanic reaction of silica fume has notable differences from Portland cement hydration.
The Importance of Portland cement Composition to Mitigate Sewage Collection Systems Damage
Authors: Rendon Luis Emilio , Lara Maria Eugenia , Rendon Montserrat 
Published: November 2012

ABSTRACTThe damage that the products of microorganism metabolism, in particular biogenic sulfuric acid, do to hardened concrete is known as concrete biodeterioration. These microorganisms, Acidithiobacillus thiooxidans, Acidithiobacillus ferrooxidans and sulfate-reducing bacteria (SRB) are ubiquitous in the environment and they produce either hydrogen sulfide or sulfuric acid that can dissolve and disintegrate the concrete matrix. Their activity plays a very important function in the whole spectrum of degradation processes such as corrosion of reinforced metals and concrete.In Canada and in the northern part of the United States, concrete structure failures from concrete biodeterioration are less common than in the southern part of the United States and in Mexico, nevertheless, it is a serious and expensive problem in hydraulic structures and sewage collection systems, which rapidly deteriorate. Also, leaking sewage systems result in the loss of groundwater resources particularly important in this arid region. Almost every city in the Mexican-American border region, who’s combined population is more than 15 million people, faces this problem. The U.S. cities have made some provision to face these concrete structure problems, but the Mexican cities have made less effort. Additives and admixtures are used to improve the properties of the concrete; nonetheless, we have exposed here the importance of the factual composition of the Portland cement and concrete to mitigate concrete biodeterioration in the hydraulic structures and sewage collection systems.
The Effect of Slag and Limestone Filler on Resistivity, Sorptivity, and Permeability of Concrete with Low Paste Content
Authors: Villagrán Zaccardi Yury A. , Di Maio Ángel A. , Romagnoli Roberto 
Published: November 2012

ABSTRACTThis paper deals with several concrete properties and to what extent they are influenced by slag and limestone filler, either one or both of them are included. Concrete was designed for low paste content, this is, a water reducing admixture (WR) was used to limit mixing water content. The results are compared with concrete made with commercial composite cement, blended during milling. Concrete was tested for compressive strength, sorptivity, resistivity, and water penetration under pressure. The volume of paste in all concrete mixes was the same.Results showed the effect of slag on concrete transport properties. The effect of limestone filler was minimal either admixed solely or in conjunction with slag. On the other hand, blended cement appeared to be less effective on improving concrete transport properties. Compressive strength was less affected than transport properties by slag inclusion.
Polycrystalline Silicon Thin Film Formed By Multiple Pulsed Rapid Thermal Annealing – Intrinsic a-Si Film Thickness Effect
Authors: Kuo Yue , Lin Chi-Chou 
Published: November 2012

ABSTRACTThe polycrystalline n+/intrinsic silicon thin film stacks with various original intrinsic amorphous silicon layer thicknesses were formed using the multiple pulsed rapid thermal annealing process with the Ni-induced crystallization mechanism. The thick polycrystalline silicon stack was prepared by repeated steps of 1) amorphous silicon thin film deposition, 2) solution oxidation, 3) dehydrogenation, 4) pulsed rapid thermal annealing, and 5) oxide stripping. The poly-Si film properties, such as the grain size, orientation, and volume fraction of the crystalline phase, were related to the original intrinsic silicon film thickness and the total thermal budget. This process is effective in preparing the high volume fraction polycrystalline silicon thin film, which is important for low-cost thin-film solar cells, electronic and optoelectronic devices.
Modeling and Experimental Study of SiH4/GeH4/H2 Gas Discharge for Hydrogenated Silicon Germanium Deposition by RF PECVD
Authors: Zhao Lai , Hunsperger Robert , Hegedus Steven 
Published: November 2012

ABSTRACTA one-dimensional model has been developed for radio frequency (RF) glow discharge of SiH4/GeH4/H2 3-gases mixture at a high pressure regime based on the fluid model. The behavior of electrons, neutrals, radicals and ions with corresponding rate constants is described by driftdiffusion equations that are coupled with the Poisson’s equation and solved with an explicit central-difference discretization scheme. The germanium (Ge) content in the deposited film and germane (GeH4) radical fraction in the gas phase are found to decrease as total gas pressure increases in contrast to the increased deposition rate, which are explained by the fact that GeHx-group species are more thoroughly depleted and less promoted by the denser plasma at high pressure compared to SiHx-group species. The multiplied population of electrons and hydrogen atoms in the quadratically denser plasma also boosts secondary reactions which are favorable for SiH3 and GeH3 and consume SiH2 and GeH2for high order radicals.
Diffuse Reflectance and Absorption Characteriation of a Plasmonic Back Reflector for Application in Thin Film Si Solar Cells
Authors: Sesuraj R.S.A. , Temple T. L. , Bagnall D.M. 
Published: November 2012

ABSTRACTA plasmonic back reflector has been fabricated for light-trapping application in thin film Si photovoltaic devices. The back reflector comprises of a 2D array of self-organized Ag NPs separated from a planar Ag mirror by a ZnO layer deposited by atomic-layer deposition. The diffuse reflectance and parasitic absorption losses can be modulated by varying the ZnO thickness. A maximum diffuse reflectance peak value of 30% at 950 nm, with a bandwidth of 400nm, is observed for ∼100 nm diameter NPs at a distance of 50 nm from the Ag mirror. Finite-difference time-domain simulations of a 100nm Ag sphere near a mirror were used to understand the experimentally observed trends in diffuse reflectance and parasitic absorption, with distance from the mirror. Particles very close to the mirror can couple to delocalized surface plasmons or exhibit Fano resonance effects, thereby increasing parasitic absorption. Particles situated away from the mirror are influenced by driving-field effects due to the interaction of incident and reflected photons, which modulate the scattering cross-section.
Light Induced Changes in PIN Solar Cells: Beyond the Staebler-Wronski Effect
Authors: Kim Ka-Hyun , Johnson Erik V. , Kasouit Samir , Roca i Cabarrocas Pere 
Published: November 2012

ABSTRACTHydrogenated polymorphous silicon (pm-Si:H) is one of the most promising candidates for a stable top cell material in multi-junction thin film solar cells. Solar cells using pm-Si:H as their absorbing layer show very interesting degradation kinetics when compared to hydrogenated amorphous silicon (a-Si:H), summarized by macroscopic structural changes and irreversible changes in solar cell characteristics, while nevertheless preserving a higher stabilized efficiency. Notably, pm-Si:H solar cells, once degraded, respond to neither annealing nor further light-soaking. Such results suggest a device degradation mechanism including structural changes, active hydrogen motion, and interface delamination mediated by fast hydrogen diffusion and accumulation at the interface. Interestingly, a similar behavior was reported for a-Si:H solar cells under severe light soaking conditions (at 350 °C or under 50 suns) while pm-Si:H solar cells show such behavior under 1 sun at 40 °C.
Artificial Photosynthesis - Use of a Ferroelectric Photocatalyst
Authors: Dunn Steve , Stock Matt 
Published: November 2012

ABSTRACTThe solid-gas phase photoassisted reduction of carbon dioxide (artificial photosynthesis) was performed using ferroelectric lithium niobate and titanium dioxide as photocatalysts. Illumination with a high pressure mercury lamp and visible sunlight showed lithium niobate achieved unexpectedly high conversion of CO2 to products despite the low levels of band gap light available and outperformed titanium dioxide under the conditions used. The high reaction efficiency of lithium niobate is explained due to its strong remnant polarization (70 μC/cm2) thought to allow longer lifetime of photo induced carriers as well as an alternative reaction pathway.
Stimulating living cells with air DBD plasma
Authors: Favia P. , Pignatelli D. , Dilecce G. , Pistillo B. R. , Nardulli M. , Gristina R. 
Published: November 2012

ABSTRACTCells positioned at the bottom of a Petri dish were exposed, in a home-made plasma source, to pulsed Dielectric Barrier Discharges operated in air in order to investigate the effect of the plasma species on their viability and growth. Processes with different number of pulse, respectively 1,3,9 and 27 pulse, were performed to study the influence on viability and cell growth of two different cell lines, Saos 2 and NHDF. Atmospheric air discharges applied on the two selected cell lines have shown an effect strongly dependent on cell type. At certain doses we have measured increased activity of the NHDF fibroblasts cell line. On the other side, an inhibition of cell adhesion and growth on the Saos 2 osteoblastoma cell line, directly dependent on the plasma doses, was clear. This study shows that by properly tuning the dose of exposure of cells to air plasma it is possible to induce both positive and negative effects on cell growth, that would be useful in several branches of Medicine.
Degradation of Influenza Virus Nucleoprotein by N2 Gas Plasma
Authors: Sakudo A , Hayashi N , Shimizu N , Imanishi Y , Shintani H 
Published: November 2012

ABSTRACTUsing a N2 gas plasma apparatus (BLP-TES, NGK Insulators, Ltd), we showed that N2 gas plasma treatment of influenza A virus caused degradation of viral nucleoproteins. These findings suggest that N2 gas plasma treatment may contribute to infection prevention control for influenza.
An Algorithm for Finding Optimized Interface Morphologies in Thin Film Silicon Solar Cells
Authors: Jäger K. , Fischer M. , van Swaaij R.A.C.M.M. , Zeman M. 
Published: November 2012

ABSTRACTWe recently developed a scattering model based on the scalar scattering theory. In this contribution we present how we used the scattering model to investigate interface textures with optimized scattering properties. We used the simulated annealing algorithm to find optimized surface textures and applied the ASA device simulator to evaluate the influence of these optimized textures on the performance of thin film silicon solar cells. We found that the lateral feature size of the textures is crucial for efficient scattering of the incident light.
The Optical Analysis and Application of Size-controllable Si Quantum Dots Fabricated by Multi-hollow Discharge Plasma Chemical Vapor Deposition
Authors: Seo Hyunwoong , Wang Yuting , Uchida Giichiro , Kamataki Kunihiro , Itagaki Naho , Koga Kazunori , Shiratani Masaharu 
Published: November 2012

ABSTRACTQuantum dot-sensitized solar cells (QDSCs) based on the multiple exciton generation (MEG) of QD are attractive in the field of photochemical cells because the improvement of conventional sensitized solar cells has been stagnant recently. The distinctive characteristics of QDs are their strong photo-response in the visible region and quantum confinement effects. Its theoretical efficiency is much higher than that of solar cell based on the single exciton generation (SEG). Moreover, QDs have tunable optical properties and band-gaps depending on the particle size. But QD materials widely used for QDSC have some disadvantages of toxicity and scarcity. On the other hand, Si as one of good QD materials is abundant and not toxic. Also, Si QD has high stability against light soaking and a high optical absorption coefficient due to quantum size effects. However, the research on Si QD is rare although the quantum effect of Si was already verified. It is one of reasons that the fabrication and collection of Si nano-particles are too difficult. Therefore, this work proposed multi-hollow plasma discharge chemical vapor deposition (CVD). It is possible to collect Si particles unlike conventional CVD and solve the problems of the wet process. The optical properties of Si particles were controlled by varying experimental conditions. In this work, Si particles were fabricated with various sizes and their characteristics were analyzed. Based on the results, Si QD was applied to Si QDSC.
Electron Spin Resonance (ESR) Observation of Radicals on Biological Organism Interacted with Plasmas
Authors: Ishikawa Kenji , Moriyama Hiroko , Tamiya Kazuhiro , Hashizume Hiroshi , Ohta Takayuki , Ito Masafumi , Iseki Sachiko , Tanaka Hiromasa , Takeda Keigo , Kondo Hiroki , Sekine Makoto , Hori Masaru 
Published: November 2012

ABSTRACTWe report the kinetic analysis of radicals on fungal spores of Penicillium digitatum interacted with charged-neutral oxygen species (O*) generated plasma discharge using real time in situ electron spin resonance (ESR) measurements. The ESR signal from the spores was observed at a g-value of around 2.004 with a line width of approximately 5G. We have successfully obtained information regarding the reaction mechanism with free radicals and realtime in situ ESR has proven to be a useful method to elucidate plasma-induced surface reactions on biological specimens
A multi-institution collaborative approach to a productive undergraduate research program in material science
Authors: Silversmith A.J. , Boye D.M. , Hoffman K.R. 
Published: November 2012

ABSTRACTWe describe our approach to a student-centered interdisciplinary research program in material science. Our work in the synthesis and optical characterization of sol-gel materials provides an ideal research setting for undergraduates interested in physics and chemistry. Students fabricate all samples and perform laser spectroscopic measurements. The work is accessible to undergraduates but also of current interest to a wide community of scientists interested in new rare earth based optical materials. Students make meaningful contributions to publishable work, and many go on to do graduate work in physics or chemistry. Two recent students have been recognized with national awards for their research, and many have presented work at international meetings.
Preparation and Characterization of Platinum/Ceria-based Catalysts for Methanol Electro-oxidation in Alkaline Medium
Authors: Menéndez Christian L. , Mayol Ana-Rita , Cabrera Carlos R. 
Published: November 2012

ABSTRACTPlatinum/Cerium oxide-based catalysts for methanol electro oxidation were prepared by the occlusion deposition technique. Composite glassy carbon (GC) electrodes were modified and then tested towards the methanol electro oxidation half reaction in acid and alkaline medium. Cyclic voltammetry and chronoamperometry techniques were used to test the catalytic response of the composite electrodes. AFM studies were carried out in order to have a measurement of the particle size and distribution of the platinum/ceria catalyst on HOPG.
An Improved In-line Inkjet Printing Process for 3D Multilayer Passive Devices
Authors: Yakoub A. , Saadaoui M. , Cauchois R. , Li J-M. , Benaben P. 
Published: November 2012

ABSTRACTThis paper describes an in-line process for the realization of 3D electronic components on A4 format substrate by piezo inkjet printing. This process is developed within a semi-industrial prototype system named “JETPAC”. JETPAC includes an oxygen plasma torch for surface preparation and post-process modules as a variable frequency microwave oven and an UV lamp for metal selective sintering and dielectric ink curing, respectively. JETPAC is used to achieve passive components by chaining conductor and dielectric layers on kapton® substrate: silver nanoparticles based ink is used to print conductors. For multilayer component elaboration, the metal ink is deposited both on kapton® and on printed dielectric materials. Due to a low surface energy (S.E) of the printed dielectric, the realization of efficient silver tracks is compromised. A special process combines O2 plasma treatment and UV exposure before printing, allowing the reaching of S.E. value on dielectric near the optimum one (55mN/m). This pre-process allows printing of well-defined conductive structures on top of the dielectric. In-line sintering of printed structures is then performed using variable frequency microwave source. The process allows the elaboration of multilayer structures including stacked resistors and capacitors. These results make the developed process very promising for the realization by inkjet printing of passive devices for smart tag applications.
Fecundity of Japanese Barberry (Berberis thunbergii) Cultivars and Their Ability to Invade a Deciduous Woodland
Authors: Brand Mark H. , Lehrer Jonathan M. , Lubell Jessica D. 
Published: November 2012

AbstractJapanese barberry is an important landscape shrub that has a demonstrated potential to be invasive in ∼30 states across the central and northern United States. Forty-six cultivars were evaluated for their potential to produce fruits and seeds in a randomized, replicated field planting. Seeds from a subset of cultivars were evaluated for their ability to germinate and survive as seedlings in a deciduous woodland. Seed production for cultivars varied from no seeds to more than 12,000 seeds plant−1and the number of seeds per fruit ranged from 0.1 to 1.8. Five cultivars produced fewer than 100 seeds plant−1, and two cultivars failed to produce fruit. When plants were allowed to mature for 4 to 5 yr beyond the first evaluation time, cultivars exhibited significant increases in fruits per plant, producing as much as 35,000 fruits plant−1(‘Sparkle’). ‘Golden Devine’ and ‘Red Chief’, fruitless cultivars at the first evaluation, produced 165 and 20 fruit plant−1, respectively, at the follow-up evaluation, demonstrating that long-term evaluation of cultivars is necessary to accurately assess sterility. Between 12.5 and 31% cultivar seed sown in a deciduous woodland germinated, and seedlings survived at rates between 5.6 and 29.3%. Coupling cultivar seed-production data with germination and survival data in a deciduous woodland suggests that even cultivars producing as few as 100 seeds annually have the potential to contribute a few seedlings each year to a natural area.
Clinical Trial Registration in Physiotherapy Journals: Recommendations From the International Society of Physiotherapy Journal Editors
Authors: Costa Leonardo O.P. , Lin Chung-Wei Christine , Grossi Debora Bevilaqua , Mancini Marisa Cota , Swisher Anne K. , Cook Chad , Vaughn Dan , Elkins Mark R. , Sheikh Umer , Moore Ann , Jull Gwendolen , Craik Rebecca L. , Maher Christopher G. , De Jesus Guirro Rinaldo Roberto , Marques Amélia Pasqual , Harms Michele , Brooks Dina , Simoneau Guy G. , Strupstad John Henry 
Published: November 2012

Clinical trial registration involves placing the protocol for a clinical trial on a free, publicly available, and electronically searchable register. Registration is considered to be prospective if the protocol is registered before the trial commences (ie, before the first participant is enrolled). Prospective registration has several potential advantages. It could help avoid trials being duplicated unnecessarily and it could allow people with health problems to identify trials in which they might participate. Perhaps more importantly, however, it tackles 2 big problems in clinical research: selective reporting and publication bias. Prospective clinical trial registration is of great potential value to the clinicians, consumers, and researchers who rely on clinical trial data, and that is why the International Society of Physiotherapy Journal Editors (ISPJE) is recommending that members enact a policy for prospective trial registration. J Orthop Sports Phys Ther 2012;42(12):978–981. doi:10.2519/jospt.2012.0111
A prospective study of physician-observed concussion during a varsity university hockey season: white matter integrity in ice hockey players. Part 3 of 4
Authors: Koerte Inga K. , Kaufmann David , Hartl Elisabeth , Bouix Sylvain , Pasternak Ofer , Kubicki Marek , Rauscher Alexander , Li David K. B. , Dadachanji Shiroy B. , Taunton Jack A. , Forwell Lorie A. , Johnson Andrew M. , Echlin Paul S. , Shenton Martha E. 
Published: November 2012

Object
The aim of this study was to investigate the effect of repetitive head impacts on white matter integrity that were sustained during 1 Canadian Interuniversity Sports (CIS) ice hockey season, using advanced diffusion tensor imaging (DTI).

Methods
Twenty-five male ice hockey players between 20 and 26 years of age (mean age 22.24 ± 1.59 years) participated in this study. Participants underwent pre- and postseason 3-T MRI, including DTI. Group analyses were performed using paired-group tract-based spatial statistics to test for differences between preseason and postseason changes.

Results
Tract-based spatial statistics revealed an increase in trace, radial diffusivity (RD), and axial diffusivity (AD) over the course of 1 season. Compared with preseason data, postseason images showed higher trace, AD, and RD values in the right precentral region, the right corona radiata, and the anterior and posterior limb of the internal capsule. These regions involve parts of the corticospinal tract, the corpus callosum, and the superior longitudinal fasciculus. No significant differences were observed between preseason and postseason for fractional anisotropy.

Conclusions
Diffusion tensor imaging revealed changes in white matter diffusivity in male ice hockey players over the course of 1 season. The origin of these findings needs to be elucidated.