bluuebunny/crossref_metadata_2025_split huggingface dataset:
Medium Range Order and 1/f Noise in Hydrogenated Silicon Thin Films
Authors: Belich T. J. , Kakalios J. 
Published: March 2017

AbstractMeasurements of the second spectra and correlation coefficients of conductance fluctuations are reported for a series of n-type doped a-Si:H films for which the deposition conditions are systematically varied. The non-Gaussian character of the 1/f noise is found to decrease with decreasing deposition temperature, which is also correlated with an increase in the difference between the conductivity and thermopower activation energies (the Q-function). The decrease in non-Gaussian statistics is interpreted as a decrease in the interactions between inhomogeneous current filaments due to increasing long-range disorder in the material.
Characterization of a-SiCx:H Films for c-Si Surface Passivation
Authors: Vetter M. , Martín I. , Orpella A. , Voz C. , Puigdollers J. , Alcubilla R. 
Published: March 2017

AbstractAmorphous intrinsic silicon carbide (a-SiCx:H(i)) films and amorphous phophorous doped silicon carbide (a-SiCx:H(n)) films deposited by plasma enhanced chemical vapor deposition (PECVD) from silane/methane mixtures provide excellent electronic passivation of p-type c-Si. Effective surface recombination velocities (Seff) lower than 23 cm s-1 have been reported for a- SiCx:H(i) films and Seff < 11 cm s-1 for a-SiCx:H(n) films. The analysis of the dependence of Seff on the injection level indicates that the good electronic passivation is due to field-effect passivation resulting from a high fixed charge (Qf) created in the a-SiCx:H film. In this work the absorption of SiH bonds in infrared transmission spectra of a-SiCx:H films is quantitatively analysed resulting in about 30% smaller amount of SiH bonds in phosphorous doped films compared to intrinsic films. Furthermore, a strong reciprocal correlation of the hydrogen content in the films and the Qf created at the a-SiCx:H/c-Si interface is observed.
Microcrystalline Silicon for Solar Cells at High Deposition Rates by Hot Wire Cvd
Authors: Schropp R. E. I. , Xu Y. , Iwaniczko E. , Zaharias G. A. , Mahan A. H. 
Published: March 2017

AbstractWe have explored which deposition parameters in Hot Wire CVD have the largest impact on the quality of microcrystalline silicon (μc-Si) made at deposition rates (Rd) < 10 Å/s for use in thin film solar cells. Among all parameters, the filament temperature (Tfil) appears to be crucial for making device quality films. Using two filaments and a filament-substrate spacing of 3.2 cm, μc-Si films, using seed layers, can be deposited at high Tfil (∼2000°C) with a crystalline volume fraction < 70-80 % at Rd's < 30 Å/s. Although the photoresponse of these layers is high (< 100), they appear not to be suitable for incorporation into solar cells, due to their porous nature. n-i-p cells fabricated on stainless steel with these i-layers suffer from large resistive effects or barriers, most likely due to the oxidation of interconnected pores in the silicon layer. The porosity is evident from FTIR measurements showing a large oxygen concentration at ∼1050 cm-1, and is correlated with the 2100 cm-1 signature of most of the Si-H stretching bonds. Using a Tfil of 1750°C, however, the films are more compact, as seen from the absence of the 2100 cm-1 SiH mode and the disappearance of the FTIR Si-O signal, while the high crystalline volume fraction (< 70-80 %) is maintained. Using this Tfil and a substrate temperature of 400°C, we obtain an efficiency of 4.9 % for cells with a Ag/ZnO back reflector, with an i-layer thickness of only ∼0.7 μm. High values for the quantum efficiency extend to very long wavelengths, with values of 33 % at 800 nm and 15 % at 900 nm, which are unequalled by a-SiGe:H alloys. Further, by varying the substrate temperature to enable deposition near the microcrystalline to amorphous transition (‘edge’) and incorporating variations in H2 dilution during deposition of the bulk, efficiencies of 6.0 % have been obtained. The Rd's of these i-layers are 8-10 Å/s, and are the highest to date obtained with HWCVD for microcrystalline layers used in cells with efficiencies of ∼6 %.
Thin-Film Transistors on PET at 100°C
Authors: Conde J.P. , Alpuim P. , Chu V. 
Published: March 2017

AbstractBottom-gate amorphous silicon thin-film transistors were fabricated on a polyethylene terephthalate substrate. The maximum processing temperature was 100°C. The transistor characteristics are comparable, although still inferior, to those of standard amorphous silicon transistors fabricated on glass substrates. To obtain these characteristics, an extended anneal the processing temperature was required. The devices were fabricated using separately optimized low-temperature active layer, contact layer and gate dielectric layer. To achieve good electronic properties for these layers, hydrogen dilution was required.
Modeling of the Band Gap Profile in the Intrinsic Layer of the a-SiGe:H Material: Application in Solar Cells
Authors: Zambrano Raul Jimenez , Rubinelli Francisco A. , Arnoldbik Wim M. , Rath Jatindra K. , Schropp Ruud E.I. 
Published: March 2017

AbstractA new band gap profile (exponential profile) for the active layer of the a-SiGe:H single junction solar cell deposited by plasma enhanced CVD (PECVD) has been designed and experimentally demonstrated. In this work we study the difference between the experimental results and the computer simulation. Using Rutherford Backscattering Spectrometry (RBS) significant differences were found between the composition profile as expected from variations in the gas phase ratio GeH4/SiH4 during the deposition and the actual Ge/Si depth profile as determined by RBS. This has important implications for the design of bandgap-graded a-SiGe:H cells. Among others, a delayed response of the plasma conditions due to the changes in the GeH4 flow is studied.
Dependence of the Lateral Photoeffect in a-Si:H P-I-N Structures on the Material Characteristics Studied by Means of a Numerical Simulation
Authors: Fantoni A. , Fernandes M. , Vieira M. 
Published: March 2017

AbstractWhen an a-Si:H p-i-n structure is locally illuminated by a light spot, the non uniformity of light causes the appearance of a gradient in the carrier concentration between the illuminated and the dark zone. Carrier start to flow in agreement with such gradients, and when equilibrium is reached, the lateral diffusion process is counterbalanced by the appearance of a lateral component of the electric field vector in addition to the transverse usual one. The lateral fields act as a gate for the lateral flow of the carriers and small lateral currents appears at the transition region between the illuminated and the dark zone. Known as lateral photo-effect, this phenomena depends on the incident light wavelength, light intensity and on the applied bias. Anyway, its intensity can be, depending on the foreseen application, alternatively enhanced or reduced by correct device engineering. We have used the 2D numerical simulator ASCA to analyze the behavior of a-Si:H p-i-n structures under local illumination with the goal of observing the appearance of the lateral components of the electric field and current density vectors. The dependence of the lateral potential redistribution on the doping density, density of defects in the intrinsic layer, and layer thickness have been analyzed. This study aims to show how material properties and device geometry can be combined in order to control the lateral photo-effect.
Short Channel Poly-Si TFT with Single Grain Boundary by Excimer Laser Annealing on Al-masked a-Si Layer
Authors: Jung Sang-Hoon , Lee Jae-Hoon , Han Min-Koo 
Published: March 2017

AbstractA short channel polycrystalline silicon thin film transistor (poly-Si TFT), which has single grain boundary in the center of channel, is reported. The reported poly-Si TFT employs lateral grain growth method through aluminum patterns, which acts as a selective beam mask and a lateral heat sink during the laser irradiation, on an amorphous silicon layer. The electrical characteristics of the proposed poly-Si TFT have been considerably improved due to grain boundary density lowered. The reported short channel poly-Si TFT with single grain boundary exhibits high mobility as 222 cm2/Vsec and large on/off current ratio exceeding 1 × 108.
Supersonic-Free-Jet CVD Growth of Dy-doped Silicon Films for 1.3 Micron LED
Authors: Kawai Shinji , Matsutake Koji , Watanabe Fumiya , Motooka Teruaki 
Published: March 2017

AbstractWe have investigated epitaxial growth of dysprosium (Dy)-doped silicon (Si:Dy) thin films for fabrication of 1.3 μm light-emitting diodes (LEDs) using supersonic-free-jet CVD. The 700-nm-thick Si:Dy films are grown on p+-type, p-type, and n-type Si(100) at a substrate temperature of 800° for 90 min. The doping concentrations of Dy atoms range from 1018 to 1019 cm-3 at the surface region of the film measured by the secondary ion mass spectrometry (SIMS). The particles with average size ~200 nm form at the surface of the film and it suggests the possibility to form Si-nanoparticle (Si quantum dots) from atomic force microscopy (AFM) observation. From the electrical measurements at room temperature, the metal (Al)-Si:Dy junction is a Schottky contact and Dy introduces donor states in Si.
Electron Spin Resonance in Magnetic Nanoparticles. Effects of Temperature and Interparticle Interactions
Authors: Noginova Natalia , Chen F. , Andreyev A. , McClure J. , Giannelis E. P. , Bourlinos A. B. , Atsarkin V. A. 
Published: March 2017

AbstractThe electron spin resonance technique has been applied to study the magnetization dynamics in broad temperature range in both concentrated magnetic fluid and diamagnetically diluted systems containing superparamagnetic maghemite nanoparticles. The ESR spectrum demonstrates an interesting double feature shape with a narrow peak near g=2, as well as “forbidden” resonances in low fields, and reveals strong dependence on temperature and nanoparticle concentration. The longitudinal spin-relaxation time was estimated. To describe the overall spectrum shape, a “quantization” model is used which involves summation of the resonance transitions corresponding to various orientations of the particle magnetic moment.
51V and 133Cs MAS NMR Investigation of Crystalline Trivanadate and Hexavanadate Phases.
Authors: Durupthy Olivier , Maquet Jocelyne , Steunou Nathalie , Bonhomme Christian , Livage Jacques 
Published: March 2017

AbstractA complete solid state NMR characterization of the vanadium oxides Cs[V3O8] and Cs2[V6O16].0.7H2O is proposed. We used 51V and 133Cs MAS NMR to investigate the local environment of cesium and vanadium nuclei and 2D 1H- 133Cs CP MAS HETCOR experiments to explore the connectivities between cesium ions and water molecules in the interlamellar space.
Coverage Dependence of CO Surface Diffusion on Pt Nanoparticles - an EC-NMR Study
Authors: Wieckowski Andrzej , Kobayashi Takeshi , Babu Panakkattu K , Chung Jong Ho , Oldfield Eric 
Published: March 2017

AbstractWe have studied the effects of CO coverage on surface diffusion rates of CO adsorbed on nanoparticle Pt catalysts in sulfuric acid media by using 13C electrochemical nuclear magnetic resonance spectroscopy (EC-NMR) in the temperature range 253 - 293 K. For CO coverage from θ = 1.0 to 0.36, the diffusion coefficients follow Arrhenius behavior and both activation energy (Ed) and pre-exponential factor (Dco) show CO coverage dependence. Ed increases from 6.0 to 8.4 kcal/mol and DCO varies from 1.1 X 10-8 to 3.7 X 10-6 cm2/s when the coverage is increased from θ = 0.36 to θ = 1.0. On the Pt catalyst surface at partial CO coverage, our data strongly support the free site hopping model of adsorbed CO as the major surface diffusion mechanism, unlike the situation found with a fully CO covered surface where CO exchange between different surface sites is believed to be the major diffusion mechanism. Our results also indicate that the contributions of lateral repulsive interactions exert a stronger influence on the diffusive motion than does the nature of the surface structure. When the diffusion coefficient was estimated from CO stripping measurements by using an electrochemical modeling protocol, the estimated diffusion coefficients were a few orders of magnitude larger than those obtained from the EC-NMR experiments. Overall these results are important for improving our understanding of electrochemical surface dynamics of molecules at interfaces, and may help facilitate better control of fuel cell reactions where the presence of surface CO plays a crucial role in controlling the reaction rates.
Vertical and horizontal composition of fecal pollution indicator bacteria in lotic and lentic ecosystems at Turkish Thrace
Authors: Altinoluk-Mimiroglu Pinar , Camur-Elipek Belgin 
Published: March 2017

Background and Purpose:Although freshwater ecosystems have natural bacterial populations, their distributions are negatively affected by agricultural activities, domestic and industrial discharges. Bacterial composition at different depths can limit the usage of the water column for drinking, irrigation or other intentions. This study was designed to give similar indications concerning the nature of distribution of indicator bacteria in two different freshwater ecosystem types (lotic and lentic biotopes), and also to identify the factors that might be responsible in shaping them.Materials and Methods:For this aim, stagnant and running water resources located in Meric-Ergene River Basin at Turkish Thrace were sampled at three water depths (surface, middle, bottom) and two sediment depths (shore and bottom) between the dates October 2014 and September 2015 at seasonal intervals. While the heterotrophic bacteria, total and fecal coliform bacteria, and Escherichia coli were recorded by the CFU and MPN techniques, some features (temperature, dissolved oxygen, pH, conductivity, salinity, nutrients, ions, and elements) were also measured by classical chemical, chromatographic or spectrometric methods.Results and Conslusions:According to the data, the bacterial distribution in each ecosystem was found as similar for the bottom and the surface water columns. Results were also supported statistically by Bray-Curtis similarity index and correspondence analyse. The relationships between the bacterial distribution and environmental features were evaluated by Spearman correlation index. Consequently, it was observed that the bacterial distribution can differ in both water column/sediment depths and lotic/lentic ecosystems. And, it was suggested that the middle water column in each ecosystem is the most proper column for human usage.
Mean resistive index as a prognostic tool for hydronephrosis in patients with acute renal colic: a study in a tertiary care
Authors: Ravindernath M. L. , Reddy G. Mahender 
Published: March 2017

Background: Uretolithiasis is one of the most common cause of urinary tract obstruction which leads to the admission into the emergency ward. The detection of urolithiasis or acute renal colic is by the radiography, conventional ultrasonography (US) and intravenous urography (IVU). A colour Doppler USG measures this change as a resistive index (RI) of the arcuate arteries at the corticomedullary junction or the interlobar arteries.Methods: 84 patients between the ages 15-50 years, who were admitted to the Emergency department of our hospital with unilateral renal colic were included into our study. Detailed demographic data was collected from all the patients and they were all subjected to a thorough physical and clinical examination. Bladder ultrasound was taken along with color Doppler for all the patients at the time of admission for every 6 hours. Thus, an increased RI index signifies an obstruction without a dilatation.Results: Left flank pain was slightly more than the right flank pain, although this was not found to be significant. Most of the patients were presented with vomiting or nausea and dysuria was seen in 48 patients. there were 41 cases of hydronephrosis in total and all of them were positive for mean RI. The specificity with the mean resistive index with color Doppler was 90%, while the sensitivity was 100%. Around 95% of the prediction was accurate with mean resistive index, with more than 90% efficiency.Conclusions: The mean resistive index is a very good tool for the diagnosis of hydronephrosis, with a very high level of specificity and sensitivity.
Role of procalcitonin and C-reactive protein in urinary tract infection diagnosis in adults
Authors: M. S. Bharath , Hiremath Ramesh S. , Basu Arini 
Published: March 2017

Background: Urinary tract infections are a common group of infections encountered in adults, and their treatment and prognosis are closely correlated with the location of infection. Clinical presentation and laboratory tests are insufficient to differentiate between upper urinary tract infection and lower urinary tract infection. So this study was conducted to explore a non-invasive diagnostic method for upper and lower urinary tract infection differentiation.Methods: A case-control study included 2 groups of patients –30 cases and 30 controls. Cases further classified into 2 groups- a) Patients having upper urinary tract infection; b) Patients having lower urinary tract infection. Patients were subjected to following tests – complete hemogram, blood C-reactive protein levels, serum procalcitonin levels, urinalysis, ultrasound abdomen.Results: Procalcitonin (PCT) and CRP values with upper urinary tract infection were significantly higher than those in with lower urinary tract infection. PCT has higher -sensitivity and a specificity than CRP.Conclusions: Both procalcitonin and CRP can be used for upper and lower urinary tract infection differentiation, but Procalcitonin has higher sensitivity and specificity in predicting Upper urinary tract infection than CRP.
To study cardiac manifestations in patients presenting with dengue infection and to find out the correlation of cardiac manifestations to warning signs of dengue
Authors: Yadav Rakesh Kumar , Kumar Sujit 
Published: March 2017

Background: This study was done to observe the presence of Electrocardiographic (ECG) changes in patients presenting with dengue infection and to evaluate whether there were any related clinical cardiac manifestations and to find out the correlation of cardiac manifestations to warning signs of dengue.Methods: The study was conducted at MLN Medical College, Allahabad in the Department of Medicine between July 2016 to December 2016. One hundred consecutive patients aged 18 years or more with positive dengue serology were interviewed and examined. ECG was done for all patients. The data was analyzed using statistical significance tests.Results: Thirty-six patients had no warning signs, 64 patients had warning signs, out of which 43 patients had two or more warning signs while 21 patients had single warning sign. Most common warning sign in this study was abdominal pain (50%) and Vomiting (45 %) while hepatomegaly was the least common warning sign. The most common cardiac abnormalities noted were rhythm abnormalities of which the commonest was sinus bradycardia, found in 60 percent. There was statistically significant correlation between cardiac manifestations and all the warning signs except lethargy/restlessness and hepatomegaly.Conclusions: The most common cardiac manifestations noted were transient rhythm abnormalities, of which sinus bradycardia was the commonest. There was no evidence of myocarditis in any of the patients. There was statistically significant correlation between cardiac manifestations and all the warning signs except lethargy/restlessness and hepatomegaly.
Rusnano i Skolkovo – czołowe rosyjskie przedsięwzięcia na drodze do innowacji
Authors: Wdzięczak Janusz 
Published: March 2017

W artykule zaprezentowano zagadnienia związane z rozwojem rosyjskiej gospodarki opartej na innowacji, a także rolę, jaką odgrywa państwo we wspieraniu rozwoju innowacji. Dokonano tego na przykładzie dwóch inicjatyw: Skolkovo i Rusnano, a także przeprowadzono próbną ocenę efektywności tych działań.
Gender Pay Gap in Poland
Authors: Oczki Jarosław 
Published: March 2017

The aim of the article is to investigate the actual and explained gender pay gaps in Poland in comparison with selected highly developed countries, and to discuss the factors determining wage disparities between men and women. Data from Eurostat EU-SILC and the International Labour Organization were used. The article concludes that the gender pay gap in Poland is relatively small and decreasing, and that estimates of the explained gender pay gap published by the International Labour Organization do not consider the influence of some important variables shaping wages.
A fuzzy model for the evaluation of suppliers of material resources to machine-building enterprises
Authors: Kozlova Evgeniya , Volynsky Vladimir 
Published: March 2017

The subject of our research is the process of selecting a supplier of material resources to machine-building enterprises. The aim of this work is to identify factors that improve the process of supplier selection of material resources to large enterprises. Testing this model is made on the example of the “KRANEKS” machinebuilding enterprise. The methodological basis of the scientific research is work in the fields of systems analysis, management accounting, and econometrics. As a result of the research, a methodology and estimation algorithm of suppliers was developed, as well as a hierarchical model of fuzzy inference to supplier evaluation. These developments are mainly aimed at supporting decision making in choosing the best provider for a machine-building enterprise. These developments mainly focused on decision support in choosing the best provider for an engineering enterprise whose list of material resources runs into the thousands. They are aimed at improving the efficiency of administrative decisions in the supplier selection process of machine-building enterprises and improving the work process of their purchasing departments.
Międzynarodowa pozycja inwestycyjna netto krajów Unii Europejskiej w latach 2006–2014
Authors: Maciejczyk-Bujnowicz Iwona 
Published: March 2017

Celem opracowania jest próba ocenienia zmian, jeśli chodzi o międzynarodową pozycję inwestycyjną netto45w krajach Unii Europejskiej w latach 2006–2014 w kontekście przestrzegania zaleceń w ramach ogłoszonej procedury zakłóceń makroekonomicznych. W niniejszej pracy dokonano przeglądu najważniejszych koncepcji teoretycznych, będących punktem wyjścia dalszych rozważań. W tym celu przeanalizowano literaturę przedmiotu oraz dane statystyczne dotyczące międzynarodowej pozycji inwestycyjnej krajów w latach 2006–2014. Na tej podstawie spróbowano ocenić współczesne tendencje dotyczące salda netto MPI w UE. W krajach UE występują znaczące różnice w przepływach kapitału mierzonego międzynarodową pozycją netto. Wybuch kryzysu w 2008 r. wywołał zmiany w tendencji w kształtowaniu się struktury kapitału w MPI. W okresie 2006–2014 następuje wzrost absolutnych wartości aktywów oraz pasywów MPI. W większości krajów UE pogłębia się ujemne saldo przepływów finansowych międzynarodowej pozycji inwestycyjnej względem PKB badanych krajów.
Disclosure of risk information in the European banking sector
Authors: Klepczarek Emilia 
Published: March 2017

A debate on the scope of bank information disclosures seems to be essential, especially after the Global Financial Crisis. The adequate quantity of data provided to the public domain is a condition of transparency of the banking sector which should assure the optimization of market participants’ decisions. There is also a tendency to unify global accountancy standards, and they are expected to ensure the same scope of disclosed information for the global financial market. The aim of the study is to investigate if there are any differences with the number of risk disclosures among the banks using GAAP and IFRS accounting standards, and if more stable banking sectors tend to report a wider scope of data. Finding out the nature of the determinants of disclosures is an important aspect in terms of working out the procedures which will increase the transparency and stability of the financial markets.