bluuebunny/crossref_metadata_2025_split huggingface dataset:
Block Copolymer Self-assembly on Ethylene Glycol (EG) Self-assembled Monolayer (SAM) for Nanofabrication
Authors: Borah Dipu , Rasappa Sozaraj , Kosmala Barbara , Holmes Justin D. , Morris Michael A. 
Published: July 2012

ABSTRACTNanostructure templates fabrication from P(S-b-MMA) thin films requires precise control of interfacial energies to achieve perpendicular orientation of microdomains to the substrate surface and can be obtained by modifying the oxide layer on silicon with a covalently anchored hydroxyl-terminated random copolymer P(S-r-MMA) termed a “neutral brush”. This commonly employed method enables precise fine-tuning of interfacial energies, but involves a lengthy process, requires starting materials that are commercially available but expensive, and results in a relatively thick under layer that can interfere with subsequent surface processing. We report here the microphase separation behaviour of an asymmetric P(S-b-MMA) diblock copolymer on electronic substrates modified with ethylene glycol (EG) self-assembled monolayer (SAM) as alternative to standard random copolymer brush. The diblock copolymer films deposited on EG SAMs upon thermal annealing spontaneously generates features with sub-lithographic resolution and pitch with perpendicular orientation. Selective etching provides a rapid route for the generation of PS template structures as the PMMA domains are etched at a faster rate. These templates can subsequently be used as etch masks to generate nanoscale features. We use state of the art lithography to generate sub-μm features and within these generate nm sized copolymer templates. Graphoepitaxy method proved a successful approach for the alignment of the microphase separated structures. This method of EG SAM driven self-0assembly provides a simple, rapid, yet tuneable approach for surface neutralization and nanofabrication technique for creating high density nanoscale features for the nanoelectronic industry.
Co-implantation : A simple way to grow doped Si nanocrystals embedded in SiO2
Authors: Mathiot Daniel , Khelifi Rim , Muller Dominique , Duguay Sébastien 
Published: July 2012

ABSTRACTCo-implantation, with overlapping implantation projected ranges, of Si and of the doping species (P, As, or B), followed by a single thermal anneal step, is proved to be a viable route to form doped Si-nc’s embedded in SiO2, with diameters of a few nanometers. Extensive results of the evolution of the Si-nc’s related photoluminescence, as a function of the dopant implanted dose, are presented and discussed. Atomic Probe Tomography (APT) is used to image directly the spatial distribution of the various species at the atomic scale. The 3D APT data demonstrate that n-type dopant atoms (P and As) are efficiently introduced in the "bulk" of the Sinanocrystals, whereas B atoms are preferentially located at their periphery, at the Si/SiO2 interface.
Nuclear Magnetic Resonance (NMR) Characterization of a Polymerized Ionic Liquid Electrolyte Material
Authors: Michan A.L. , Nguyen G.T.M. , Fichet O. , Vidal F. , Vancaeyzeele C. , Michal C.A. 
Published: July 2012

ABSTRACTSolid electrolyte materials have the potential to improve performance and safety characteristics of lithium-ion batteries by replacing conventional solvent-based electrolytes. A candidate solid polymer electrolyte, AMLi/PEGDM, has been synthesized by crosslinking an anionic monomer AMLi, with poly(ethylene glycol) dimethacrylate. The main goal of the synthesis is to produce a single-ion conducting polymer network where lithium cations can move freely and fluorinated anions are immobilized as part of the polymer network. A comprehensive characterization of anion and cation mobility in the resulting material is therefore required. Using pulsed-field gradient nuclear magnetic resonance (PFG-NMR), we are able to measure and quantify the individual diffusion coefficients of mobile species in the material (19F and 7Li) and confirm the extent to which the fluorinated anionic component is immobilized. We have characterized dry (σ~3.0 x10-7 S/cm at 30°C) and propylene carbonate (PC) saturated gel (σ~1.0x10-4 S/cm at 30°C) samples. Experimental results include NMR spin-spin and spin-lattice relaxation times in addition to diffusion coefficient measurements over a temperature range up to 100°C. Practically, the diffusion measurements are extremely challenging, as the spin-spin (T2) relaxation times are very short, necessitating the development of specialized pulsed-field gradient apparatus. Diffusion coefficients for the most mobile components of the lithium cations and fluorinated anions at 100°C in dry membranes have been found to be 3.4 x10-8 cm2/s and 2.1 x10-8 cm2/s respectively. These results provide valuable insight into the conduction mechanisms in these materials, and will drive further optimization of solid polymer electrolytes.
Atomic and electronic structure of superionic solid electrolyte Li10GeP2S12
Authors: Xiong Ka , Pazos Roberto Longo , Cho Kyeongjae 
Published: July 2012

ABSTRACTWe investigate the electronic structure of interstitial Li and Li vacancy in Li10GeP2S12 by first principles calculations. We find that the Li vacancy and interstitial Li+ ion do not introduce states in the band gap hence they do not deteriorate the electronic properties of Li10GeP2S12. The energy barrier for Li interstitial diffusion in Li10GeP2S12 is estimated to be 1.4 eV, which is much larger than that of the Li vacancy in Li10GeP2S12. This fact suggests that the ion conductivity arises from the migration of Li vacancy.
Density modulated multilayer silicon thin films as li-ion battery anodes
Authors: Demirkan M. Taha , Li Xin , Wei Bingqing , Karabacak Tansel 
Published: July 2012

AbstractIn this work, we demonstrate a new density modulated multilayered silicon thin film anode approach that can provide a robust high capacity electrode for Li-ion batteries. These films have the ability to tolerate large volume changes due to their controlled microstructure. Silicon films with alternating layers of high/low material density were deposited using a DC sputtering system. Density of the individual layers was controlled by simply changing the working gas pressure during sputtering. Samples of Si films having thicknesses of 460 nm with different number of high/low density layers have been deposited on Cu current collectors. The electrochemical performance of the multilayered anode material was evaluated using a galvanostatic battery testing system at C/10 rate. After reaching a stabilized phase the battery cell showed a high coulombic efficiency of 96% to 99% and reversible specific capacity of 666 mAh g-1 (after 100 cycles). Low-density layers are believed to be acting as compliant sheets during volume expansion making the films more durable compared to conventional Si film anodes. The results indicate that density modulated multilayer Si thin films can be used to improve the mechanical properties of Li-ion battery anodes leading to high reversible capacity values even after high number of cycles.
Investigating the Photoelectrochemistry of Transparent ZnO Grown on ITO/Plastic for Flexible Photoelectrochemical Cell and Photovoltaic Application
Authors: Suzuki Yuji , Kathirgamanathan Poopathy , Nathan Arokia 
Published: July 2012

AbstractZnO was electrochemically grown on ITO coated polyethylene (PET) substrate. By sandwiching the electrolyte (sodium para-toluene sulfonate) with so grown ZnO/ITO/PET substrate with another ITO/Plastic substrate, a transparent ZnO based flexible PV cells was fabricated. The efficiency of 0.3% was obtained when shined under UV light. It was concluded that there will be a significant trade-off between with its performance although the optical transparency is very attractive.
Does rapid maxillary expansion induce adverse effects in growing subjects?
Authors: Lione Roberta , Franchi Lorenzo , Cozza Paola 
Published: July 2012

Abstract

Objective:
To assess the scientific evidence that rapid maxillary expansion (RME) causes Adverse Effects on the midpalatal suture, vertical dimension, dental and periodontal structures in growing subjects.

Materials and Methods
Electronic databases were searched for articles dated through December 2011. The quality of the studies was ranked on a 13-point scale in which 1 was the low end of the scale and 13 was the high end.

Results:
Thirty relevant articles were identified. The amount of midpalatal suture opening ranged from 1.6 to 4.3 mm in the anterior region and from 1.2 to 4.4 mm in the posterior region. At the end of the active phase, RME resulted in slight inferior movement of the maxilla (SN-PNS +0.9 mm; SN-ANS +1.6 mm), increased tipping of anchored teeth from 3.4° to 9.2° and bending of the alveolar bone from 5.1° to 11.3°. In the long term, RME did not modify the facial growth patterns, and no significant changes on dentoalveolar structures were observed. Of the 30 studies, 2 were medium-high quality, 8 were medium quality, and 20 were low quality.

Conclusions:
RME always opened the midpalatal suture in growing subjects. The vertical changes were small and transitory. In the long-term evaluation, an uprighting of anchored teeth was observed and periodontal structures were not compromised.
A prospective randomized split-mouth study on pain experience during chairside archwire manipulation in self-ligating and conventional brackets
Authors: Bertl Michael H. , Onodera Kanji , Čelar Aleš G. 
Published: July 2012

ABSTRACT

Objective:
To investigate patient discomfort during archwire engagement and disengagement in patients treated with self-ligating and conventional brackets using a split-mouth design.

Materials and Methods:
Eighteen consecutive patients (15 female, 3 male; age: 22.2 ± 6.4 years) who requested treatment with fixed orthodontic appliances were randomly assigned for bonding with SmartClip self-ligating brackets on one side of the dentition and conventional standard edgewise brackets on the other. During the course of treatment, patients rated the discomfort experienced during every archwire engagement and disengagement using a numeric rating scale. Results were evaluated for round and rectangular nickel titanium and rectangular stainless steel, titanium molybdenum, and Elgiloy archwires. Patients also rated their overall experience retrospectively for both bracket systems.

Results:
Regardless of archwire type, disengagement was rated as being significantly more painful on the SmartClip side (P  =  .027). For rigid, rectangular archwires, engagement and disengagement were rated as being significantly more painful on the SmartClip side (P  =  .031; P  =  .004). Retrospective ratings favored conventional brackets beyond ratings recorded during treatment.

Conclusion:
Engagement and disengagement of rigid rectangular archwires caused more pain with SmartClip self-ligating brackets than with conventional ones. Careful archwire manipulation and patience during full alignment are essential for limiting chairside pain. Low pain levels will help ensure treatment satisfaction and compliance.
Limiting distribution for a simple model of order book dynamics
Authors: Kruk Łukasz 
Published: July 2012

Abstract
A continuous-time model for the limit order book dynamics is considered. The set of outstanding limit orders is modeled as a pair of random counting measures and the limiting distribution of this pair of measure-valued processes is obtained under suitable conditions on the model parameters. The limiting behavior of the bid-ask spread and the midpoint of the bid-ask interval are also characterized.
Evaluating Fertilizer Application Strategy for Improving Crop Yields and Reducing Mineral Nitrogen Leaching in High Rainfall Areas of Taiwan
Authors: Adhikari Keshav R 
Published: July 2012

A 2-yr pot experiment conducted on an upland sandy clay loam soil in National Taiwan University, Taipei evaluated crop yields and mineral nitrogen (Nmin) leaching as affected by fertilizer application strategy, viz., inorganic (100% N from urea), organic (100% N from compost), combined (compost plus urea) and a zero control (Ctrl) treatments. Cabbage (Brassica oleracea L.) and corn (Zea mays L.) were grown in annual rotation under simulated high rainfall conditions. The Nmin leaching was monitored adding 83 and 62 mm of water fortnightly to cabbage and corn respectively for a total of 28 times. One-way ANOVA was used to determine the statistical significance of treatment effect and Tukey test for means comparisons (p = 0.05). Treatment differences were subtle for dry matter yields (DMY) but the treatments were strikingly different for 2-yr cumulative Nmin leaching (6.66% in organic, 30.6% in inorganic and 8.10% in combined treatments). This difference was largely related to the ability of soil to an increased retention of added N under organic and combined fertilization treatments. Unlike reported elsewhere, N recoveries were relatively high in compost applied soils, with or without urea fertilizer application. It is concluded that framers’ practices of fertilization that has inherent problem of excessive N leaching in high rainfall areas of Taiwan could be improved by proper compost and urea combinations within agronomically recommended rate of N application.DOI: http://dx.doi.org/10.3126/njst.v12i0.6472 Nepal Journal of Science and Technology 12 (2011) 7-16
Effect of Integrated Nutrient Management on the Growth, Yield and Soil Nutrient Status in Tomato
Authors: KC Prativa , Bhattarai BP 
Published: July 2012

A field experiment was conducted at the Integrated Research Farm of Himalayan College of Agricultural Sciences and Technology (HICAST) at Bandegaon, Lalitpur, Nepal during 2009 to scrutinize the effect of Integrated Nutrient Management (INM) on the growth, yield and soil nutrient status to tomato (Lycopersicon lycopersicum (L.) Karsten). Following a randomized complete block design, 9 treatments with 3 replications were maintained. The study revealed that the integration of organic manures in combination with inorganic fertilizers was found significant in improving the overall plant growth, yield and soil macro nutrient status than the sole application of either of these nutrients. Maximum plant height and number of leaves per plant were observed with treatment 16.66 mt/ha FYM + 8.33 mt/ha Vermicompost + NPK. The earlier of days to 50% flowering was observed in treatment 20 mt/ha FYM. Highest number of fruit clusters, maximum fruit weight and fruit yield (25.74 mt/ha) were recorded in treatment 16.66 mt/ha FYM + 8.33 mt/ha Vermicompost + NPK. The pH value was found near to neutral in treatment 10 mt/ha vermicompost. Similarly, the maximum organic matter percentage was also recorded in treatment 10 mt/ha vermicompost. The highest available nitrogen, phosphorus and potassium were found in treatment ½ NPK + 15 mt/ ha vermicompost.DOI: http://dx.doi.org/10.3126/njst.v12i0.6474 Nepal Journal of Science and Technology 12 (2011) 23-28
Effect of Azotobacter and Nitrogen Levels on Fruit Yield and Quality of Bell Pepper
Authors: Bhattarai Dhruba R , Poudyal Krishna P , Pokhrel Shanta 
Published: July 2012

Inorganic fertilizers alone cannot sustain high levels of productivity. It may cause deterioration of soil environment leading to low productivity. An investigation was carried out to develop integrated nutrient management technology for fruit yield of bell pepper (Capsicum annuum L.). The experiment was conducted at Horticulture Research Division, Nepal Agricultural Research Council Khumaltar, Lalitpur during 2010/011. The experiment was laid out in a randomized block design with three replications and having seven treatments viz., Control (100% NPK), Azotobacter + 25% N + PK, Azotobacter + 50% N + PK, Azotobacter + 75% N + PK, Azotobacter + FYM + 25% N + PK, Azotobacter + FYM + 50% N + PK, Azotobacter + FYM + 75% N + PK. Among the tested treatments, T7 (Azotobacter + FYM + 75 % N + PK) recorded the maximum plant height (66.18 cm), number of primary branches (8.20) and fruit yield (18.08 kg) per plot.DOI: http://dx.doi.org/10.3126/njst.v12i0.6475 Nepal Journal of Science and Technology 12 (2011) 29-34
Optimization of RAPD-PCR Conditions for the Study of Genetic Diversity of Centella asiatica
Authors: Devkota Anjana , Bimb Hari P , Bajracharya Jwala , Jha Pramod K 
Published: July 2012

Random amplified polymorphic DNA (RAPD) is one of the molecular marker tools available for detecting the polymorphism in plant species. It has been used extensively for genetic diversity studies. In the present investigation, the RAPD reaction and cycling conditions were optimized for generating RAPD fingerprints of twenty one ecotypes of Centella. asiatica (L.) urban collected from different locations of Nepal. To determine the optimum conditions for PCR amplification, different concentrations of master mix ( 2X mix , Promega USA), template DNA, primer and PCR cycling conditions were varied. Reproducible amplified products were observed using 0.5 ?M of primer, 12.5?l master mix (2X), and 100 ng of template DNA in 25?l reaction volume of PCR. Cycling conditions were optimized with varying annealing temperature and initial denaturation temperature. The best cycling condition comprised of an initial denaturation of 3 min at 94°C, followed by 30 cycles of denaturation for 45 sec at 94°C, annealing for 1 min at 37°C, and extension for 1 min at 72°C and final extension at 72°C for 7 min . Of the 21 random primers tested, only 8 primers produced the best and reproducible amplification products. The optimized RAPD-PCR conditions and selected primers were subsequently used for the study of genetic diversity in C. asiatica.DOI: http://dx.doi.org/10.3126/njst.v12i0.6482 Nepal Journal of Science and Technology 12 (2011) 69-74
Micropropagation of Cymbidium iridioides
Authors: Pant Bijaya , Swar Sangeeta 
Published: July 2012

Seeds of Cymbidium iridioides D. Don, a highly collected orchid species of Nepal, has been developed were cultured on Murashige and Skoog, 1962 (MS) static media solidified with 0.8% agar. Complete seedlings were obtained from asymbiotically germinated seeds on MS media supplemented with 6- benzyalaminopurine (BAP) 1 mg/l plus ?-naphthaleneacetic acid (NAA) 1 mg/l in eight weeks of primary culture. The shoot tip explants were obtained from in vitro grown seedling for the shoot multiplication. Maximum number of shoots were developed from shoot tip explants on MS media supplemented with BAP 0.5 mg/l (8.25 shoots per single shoot). This ability did not decline even after a year of subculture. For rooting of shoots the media was supplemented with various auxins. Media supplemented with 1mg/l indole-3-butyric acid (IBA) was the ideal condition for root formation. Thus obtained complete plantlets were able to grow in community pots after a short period of acclimatization. This result suggests that the methodology might be applied as an alternative to minimize the over exploitation of the natural population of this species.DOI: http://dx.doi.org/10.3126/njst.v12i0.6485 Nepal Journal of Science and Technology 12 (2011) 91-96
X-ray Photoelectron Spectroscopic Study on the Anodic Passivity of Sputterdeposited W-Ta Alloys in 12 M HCl
Authors: Bhattarai Jagadeesh 
Published: July 2012

The role of a simultaneous additions of tungsten and tantalum on the anodic passivity of the passive films of the sputter-deposited nanocrystalline W-xTa alloys was studied using immersion tests, electrochemical measurements and X-ray photoelectron spectroscopic (XPS) analysis. The formation of spontaneous passive film on the alloys, which is composed of double oxyhydroxide of tungsten and tantalum ions are responsible for their higher corrosion resistance than those of the alloy-constituting elements in 12 M HCl solution open to air at 30°C. The quantitative surface analysis by XPS is clarified that the improved anodic passivity of the alloys than those of alloy-constituting elements is based on the formation of new anodic passive oxyhydroxide films composed of W6+ and Ta5+ ions. These films have higher protectiveness and stability than those of passive oxyhydroxide films of alloy-constituting elements, that is, oxyhydroxides of hexavalent tungsten and pentavalent tantalum after potentiostatic polarization for 1 h in 12 M HCl.DOI: http://dx.doi.org/10.3126/njst.v12i0.6492 Nepal Journal of Science and Technology 12 (2011) 139-148
Influence of Uncoupled Diblock Molecules on Mechanical Properties of Styerene/Butadiene/ Styrene Triblock Copolymers
Authors: Adhikari Rameshwar 
Published: July 2012

The influence of the presence of uncoupled polystyrene-block-polybutadiene (SB) diblock chains to polystyrene-block-polybutadiene-block-polystyrene (SBS) triblock copolymers on the mechanical properties of the latter has been studied by means of tensile testing and dynamic mechanical analysis preparing several lamellae forming SBS/ SB blends through solution casting. The microphase-separated morphology of the samples was investigated by transmission electron microscopy. Both large strain deformation tensile deformation behaviour and viscoelastic properties of the SBS block copolymers were found to be affected appreciably by the presence of uncoupled SB diblock. The storage modulus of linear SBS was found to drop more sharply in the plateau region than for the radial SBS at the same SB content. At low SB content (up to 20 wt.-% for linear SBS and still higher for radial one), the overall tensile properties was not negatively influenced. On the whole, star block copolymers were found to be less sensitive towards the presence of diblock.DOI: http://dx.doi.org/10.3126/njst.v12i0.6493 Nepal Journal of Science and Technology 12 (2011) 149-156
Brine-shrimp Bioassay for Assessment of Anticancer Property of Essential Oils from Spices
Authors: Bajracharya Gan B , Tuladhar Sarbajna M 
Published: July 2012

The potential anticarcinogenicity of essential oils from spices was investigated against brine-shrimp (Artemia salina) nauplii. The essential oils were extracted by hydro-distillation. The lethal concentration at the dose levels 10, 100 and 1000 ìg/ml displayed high mortality towards actively swarming Artemia. Asafoetida (LC50 = 4.64 ×10–23 ìg/ml) and cumin oil (LC50 = 0.53 ìg/ml) were extremely toxic. Essential oils of ajowan, small cardamom, cinnamon, clove, coriander, cubeb, dill, fennel, ginger, mace, nutmeg, long pepper, rosemary, tarragon and thyme were shown high toxicity. While big cardamom oil and black pepper oil were displayed moderate toxicity.DOI: http://dx.doi.org/10.3126/njst.v12i0.6495 Nepal Journal of Science and Technology 12 (2011) 163-170
Phytochemicals, Traditional Uses and Processing of Aconitum Species in Nepal
Authors: Shyaula Sajan L 
Published: July 2012

The tuberous roots of genus Aconitum are commonly applied for various diseases, such as rheumatic fever, painful joints and some endocrinal disorders. It stimulates the tip of sensory nerve fibers. These tubers of Aconitum are used in the herbal medicines only after processing. At the mean time, there remain high toxicological risks of the improper usages of Aconitum. The cardio- and neurotoxicity of this herb are potentially lethal. Some of the species like A. ferox and A. spicatum are deadly poisonous while others like A. oreochryseum and A. bisma are used as the antidote for Aconitum poisoning. It is therefore, a valuable drug as well as an unpredictable toxic material. In the current review, assessments of Aconitum species are carried out, to increase knowledge for the safety uses, in context of Nepal. The traditional uses, phytochemical studies, its processing techniques and toxicological principles are reviewed.DOI: http://dx.doi.org/10.3126/njst.v12i0.6496 Nepal Journal of Science and Technology 12 (2011) 171-178