Miracle-dz/UniFAR-FTUs huggingface dataset:
Infrared spectroscopic study of SiOx films produced by plasma enhanced chemical vapor deposition

We have studied the local atomic structure of silicon suboxide (SiOx, x<2) thin films using infrared (IR) spectroscopy. The films were prepared by plasma enhanced chemical vapor deposition (PECVD) of silane (SiH4) and nitrous oxide (N2O) mixtures, which were then diluted with He. The IR spectra were found to vary significantly with the degree of He dilution. Films grown with no He showed SiN, NH, and SiH bonding groups in addition to the three characteristic vibrations of the Si–O–Si linkage. The addition of He reduced the strength of the SiN, NH, and SiH absorption bands, and resulted in systematic increases in the frequency of the Si–O–Si asymmetric stretching vibration. The frequency of this Si–O–Si stretching vibration scales linearly with the oxygen concentration from approximately 940 cm−1 in oxygen doped amorphous silicon to 1075 cm−1 in stoichiometric noncrystalline SiO2. A deposition temperature of 350 °C and a He dilution of 50% gave a film composition close to SiO1.9. We propose a model for the.
Behaviour of fipronil in soil under Sahelian Plain field conditions

The behaviour of fipronil, a phenylpyrazole insecticide used for locust control, was studied under sub-Saharan conditions in soils of the Niamey region of Niger. A formulation of fipronil (Adonis®) was applied to uncultivated soils at Banizoumbou and Saguia. Soil was sampled at 0–10, 10–20 and 20–30 cm depths for up to two months after treatment. Residues were analysed by gas chromatography using electron capture and mass detectors. For both soils, a rapid initial decrease of fipronil was observed, with rapid formation for the most part of a photodegradate. Three other metabolites of fipronil were also detected throughout the study. These metabolites displayed different dissipation kinetics. Fipronil and its metabolites did not move beyond 10 cm depth, except for the amide, which is not considered a toxicologically significant metabolite. © 1998 SCI.
Environmental factors affecting the formation of methylmercury in low pH lakes

Recent studies have demonstrated elevated levels of mercury in fish from remote, low alkalinity and low pH lakes. The mechanisms of this enhanced bioaccumulation are poorly understood, but the amount of methylmercury produced in a lake can play a major role. Decreased pH stimulates methylmercury production at the sediment-water interface and possibly in the aerobic water column. Decreased pH also decreases loss of volatile mercury from lake water and increases mercury binding to particulates in water – factors that may increase methylation at low pH by enhancing the bioavailability of mercury for methylation. In anoxic subsurface sediments, decreased pH decreases the rate of mercury methylation, suggesting that methylmercury formation in the water column and at the sediment-water interface may be most important in acidified lakes. Sulfate-reducing bacteria are important mercury methylators in acidified lakes. Whether enhanced sulfate reduction stimulates methylmercury production in low pH lakes is presently unclear, although most of the available data do not support this hypothesis.
Aggregation of Anionic and Nonionic Poly(oxyethylene) Surfactants in Multicomponent Systems, as Studied by the Spin Probe Technique: Location of the Vinyl Acetate Component

A structural characterization of the multicomponent system poly(oxyethylene)surfactant/water/ethanol/vinyl acetate has been attempted, using the spin probe technique. Four spin probes with various polarities have been used to probe the formation of surfactant aggregates, as well as their structural characteristics (local polarity, microviscosity, and order of the surfactant chains) vs composition for a series of monophasic samples with a constant ethanol/vinyl acetate ratio. The composition ranges where aggregation occurs are shown. It has been shown that, while vinyl acetate is solubilized in the poly(oxythylene) region of the aggregates, ethanol does not seem to be involved in the aggregate construction.
The Impact of e-NPQEL on the Continuance Intention of Using e-Training among Aspired School Leaders in Malaysia

Information and communication technology (ICT) has become an important platform for e-training as it offers many advantages in providing new knowledge and skills for professional development. This study aims to examine the impact of e-NPQEL on the continuance intention of using online learning among aspired school leaders in Malaysia. From the data analysis, results revealed the features of e-NPQEL that influence the perceived usefulness of the participants on the program and the mediating effect of this aspect on the relationship between e-NPQEL features and continuance intention. The results of this study imply to the Human Resource managers that intend to have e-training for their professional development agendas.
High tar reduction in a two-stage gasifier

The work with a 100-kWth two-stage gasifier at the Technical University of Denmark (DTU) has resulted in a gas with a very low tar content. The reduction in tar has come about by combining the partial oxidation of the pyrolysis gas with the reactions that follow on a charcoal bed in the char gasification unit. Tar is defined as organic contaminants which have retention times equal to or greater than those of phenol on a nonpolar GC column. Two test series were made with wood chips as feedstock, before and after the gasifier was optimized. The effect on tar reduction of a charcoal bed has been investigated by measuring the tar content and composition of the gas after the partial oxidation (above the charcoal bed) and after the passage of the gas through the charcoal. By introducing the correct supply of air, the tar content in the gas after its partial oxidation was about 3000 mg/kg dry wood chips. Furthermore, a conclusive high tar reduction of the aromatic hydrocarbons including PAH was obtained by avoid.
Effects of the dietary grain content on rumen and fecal microbiota of dairy cows

Abstract: Six non-lactating Holstein dairy cows received diets with forage to grain mixture ratios of 100:0 (G0), 75:25 (G25), and 50:50 (G50) that contained 0.5%, 10.0%, and 19.5% dry matter (DM) of starch, respectively. Rumen fluid and feces were sampled, and methane emissions were determined during the last week of 5 wk experimental periods. Taxonomic compositions of microbiota were determined using Illumina 16S rRNA sequencing. Increased grain feeding increased the acidity and volatile fatty acid concentrations of rumen fluid and feces, and decreased methane emissions expressed as L·kg−1 DM. Microbial diversities were highest for G25. The numbers of identified genera in rumen fluid were 185, 182, and 171 for G0, G25, and G50, respectively. In feces, these numbers were 197, 182, and 171 for these diets, respectively. In rumen digesta, seven genera were correlated positively to G0 and negatively to G50, and six genera were correlated negatively to G0 and positively to G50. In feces, 16 genera were correlated positively to G0 and negatively to G50, and 13 genera were correlated negatively to G0 and positively to G50. Increasing grain feeding affected a limited number of genera in rumen digesta and feces. This could not explain treatment effects on the functionalities of microbiota.
Improved Fine Coal Dewatering by Ultrasonic Pretreatment and Dewatering Aids

The effects of ultrasonic pretreatment and surface active reagents to improve the efficiency of fine coal dewatering in high frequency vibrating screen have been carried out. The results showed that hydrophobic surface active reagents increased the contact angle and decreased surface tension of the solution reducing the moisture content of fine coal particles. Polyethylene glycol 400 monooleate (PEG-400) was found to be the most effective reagent. Furthermore, when ultrasonic pretreatment was introduced to the fine coal slurry, the residual total moisture content of the fine coal was further decreased.
Determination of Mercury Binding Forms in Contaminated Soils: Mercury Pyrolysis versus Sequential Extractions

Binding forms of mercury (Hg) in contaminated soils were studied by means of a pyrolysis method and a sequential leaching procedure (SEP). Changes of the Hg-binding forms occurring during the sequential extraction procedure were characterized by determination of the thermal mercury release characteristics after each extraction step. Soil samples were selected from the site of a former chloralkali plant, a wood preservation site, and two mining areas contaminated by metallic mercury (Hg0), mercury(II) chloride (HgCl2), or mercury sulfide (HgS), respectively. The results show that Hg0, matrix-bound Hg, and HgS occurring in the studied soils could be identified by their thermal release behavior. In contrast, results obtained from sequential leach ing did not allow the identification of any specific Hg compounds as in all samples most of the Hg is extracted in the nonspecific residual Hg fraction. Results of pyrolitic measurements after each extraction step demonstrated the insufficient selectivity of the use.
Resuspension of Dust Particles in a Chamber and Associated Environmental Factors

Experiments investigating particle resuspension from human activities were conducted in a full-scale experimental chamber. The experiments tested three types of flooring (vinyl tiles, new and old level-loop carpets) and two ventilation configurations (ceiling and side wall supply systems). The floorings were seeded with 0.1–10 μ m test particles. The airborne particle concentration was measured by an array of optical particle counters (OPCs) in the chamber. Resuspension rates were estimated in size ranges of 0.8–1, 1.0–2.0, 2.0–5.0, and 5.0–10 μm ranging from 10−5–10−2 hr−1, with higher resuspension rates associated with larger particles. Resuspension via walking activity varied from experiment to experiment. “Heavy and fast” walking was associated with higher resuspension rates than less active walking, most likely due to a combination of increased pace, increased air swirl velocity, and electrostatic field effects established by the walking. The type of floorings also influenced the particle resuspension. Given the same size and mass distribution of test particles per unit floor area, resuspension rates for the seeded new level-loop carpet were significantly higher than those for the vinyl tile flooring for larger particles (1.0–10 μ m) under the ceiling air supply system.
Year and Industry-level Accounting Narrative Analysis: Readability and Tone Variation

In this study, I examine variations in the textual complexity of annual report narrative disclosures using the Fog Readability Index and Fin-Neg word list Tone Index given year and industry effects. I analyse accounting narrative Readability and Tone based on firm years, associations between the two narrative measures, and industry data. Tests of the relationship between Readability and Tone show that negative narratives have higher Readability scores, supporting the obfuscation hypothesis that bad news tends to be more difficult to read. A year analysis shows that the negative relationship between Readability and Tone increases in significance over time (2006-2011). An industry analysis shows that the observed obfuscation tends to persist in basic materials; consumer services; financial; technology; and utilities industries. This study shows that considering the effect of variations between industry and firm years can inform annual report textual complexity research and associated empirical analyses.
Synthesis and Characterization of Ordered Mesoporous Carbon/Silica Hybrid Thin Films

Carbon/silica nanocomposite films with a hexagonal P6mm structure were fabricated directly by the oxidation and carbonization of surfactant/silica nanocomposite films, which were obtained by a dip-coating technique through a combination of sol-gel and evaporation-induced self-assembly. The as-synthesized nanocomposite films were characterized by scanning electron microscopy, X-ray diffraction, transmission electron microscopy and N2 adsorption-desorption. These analyses reveal that the carbon/silica nanocomposite films, with a narrow pore size distribution of mesopores, have an ordered symmetric structure. The pore sizes of this hybrid film can be controlled within a certain range by changing the carbonization temperature. In addition, the films are composed of a continuous silica matrix and a continuous carbon coating in about 1 nm adhered well to the silica matrix. The formation of carbon coatings from surfactant acts as a framework support to prevent the pore size of the silica matrix from shrinking.
Service centers: analysis of challenges at different developmental stages

Purpose – To link the different levels of maturity of Service Centers (SCs) in multinational companies to the challenges faced by this organizational arrangement. Design/methodology/approach – Using a qualitative approach, we conducted a multiple case study with data collection, via semi-structured interviews, with managers of three multinational companies, based in SCs in southern and southeastern Brazil. The interviews were recorded and transcribed, and a content analysis was made based on four pre-defined categories using a theoretical framework. Findings – Results show that challenges arise depending on the Center's level of development and are related to organizational structure; cost reduction; customer relationship management; and processes. Some challenges have always recurred at SCs, others are not relevant initially, and then become more important, while others decrease in complexity over time. Originality/value – As a theoretical contribution, in addition to proposing a three-stage analysis, this study demonstrates the importance of examining each with its specific challenges. The understanding that a SC develops based on tensions and solutions demonstrates the dynamics and complexity of this phenomenon. The study also encourages and guides managers in organizations, who are planning a SC or who already have one set up, to align their resources and work with the measures needed to deal with the challenges of each stage and maximize the use of resources for better results at the SC. Keywords - Service Center. Service Center Stages. Organizational management
Cryptococcal Meningitis Presenting as Endophthalmitis in an Otherwise Asymptomatic Patient

Purpose: Cryptococcus neoformans is a budding yeast that has a tropism for the central nervous system where it may cause meningitis, which has a high mortality rate. Endophthalmitis is rare and typically occurs in the setting of meningitis and disseminated disease. This report describes an atypical presentation of cryptococcal endophthalmitis and outlines the appropriate workup and management for this disease. Methods: A case report is presented. Results: A 66-year-old man on chemotherapy who presented with blurry vision without any extraocular symptoms was diagnosed with cryptococcal endophthalmitis and found to have underlying bloodstream and central nervous system infection on subsequent workup. He was treated with intravenous and intravitreal antifungals and remained systemically well, although a large subretinal mass lesion remained stable at 2-month follow-up. Conclusions: Cryptococcal endophthalmitis may be the initial presentation of disseminated cryptococcal disease. If vitreous cultures grow Cryptococcus, clinicians should presume that meningitis is present, regardless of symptoms, until proven otherwise.
Well-defined colloidal tin(IV) oxide particles

Spherical and rod-like SnO_2 particles of narrow size distribution have been obtained by aging at 100°C acidified tin(IV) chloride solutions in the presence of urea or formamide. It was shown that spherical particles, the x-ray diffraction of which was characteristic of cassiterite, consisted of a large number of much smaller subunits. The rod-like particles had the same structure, but of higher degree of crystallinity. Infrared spectra of these powders were evaluated in terms of the theory of the average dielectric constant (TADC), in order to gain additional information on the particle morphology and the state of aggregation.
Comparison of Regenerative Potential of Platelet-rich Fibrin Alone and in Combination with Bovine Bone Graft in Intraosseous Defect by Single Flap Approach: A Clinical and Radiographic Study

ABSTRACT Aim: To compare the regenerative potential of platelet-rich fibrin alone and in combination with bovine bone graft in intraosseous defect by the single flap approach. Materials and Methods: A total of 32 sites of intrabony defects were selected and were treated with platelet-rich fibrin (PRF) alone or in combination with bovine bone graft. Clinical parameters [Gingival index (GI), probing depth (PD), clinical attachment level (CAL), Gingival recession, and radiographic parameters (defect fill, alveolar crest level, and defect depth)] were recorded at baseline, 3 months, and 6 months. Results: Statistical analysis was done by independent and paired t-test. There were statistically significant changes in GI, PD reduction, CAL gain, defect fill, alveolar crest level changes, and defect depth resolution from baseline, 3 months, and 6 months in both the groups (P < 0.001). On intergroup comparison, Group II showed statistically significant changes in a reduction in pocket depth and defect depth resolution at P < 0.001. Conclusion: PRF in combination with bovine bone graft was more effective in the treatment of intrabony defects.
Watching of Scary TV Shows by Children and Youth, Identification With Characters, and Resulting Fears and Nightmares

The identification of children and adolescents with characters from the television programs they watch is not limited to the time when they view the program. The connection with the characters continues across the use of various digital means and in various realms of the children’s lives. The purpose of the present study was to examine the connections between patterns of use of various media, the degree of identification with characters from the programs watched, and the fears and nightmares experienced by the children after watching these programs. This is a mixed-method study. Two hundred ninety-six Israeli children and adolescents participated in the study; 45 children and adolescents among those who completed questionnaires were interviewed. The data were collected in 2017-2018. The data revealed that negative identification with the show characters was higher among children than in adolescents. Positive identification with the characters was higher among viewers of scary programs, among those who suffered from nightmares and fears, and among those who perceived the characters and plot as realistic. It was found that interest in programs involving tension, drama, and action increases the risk of nightmares and fears after watching these programs.
Constituent properties of HMX needed for mesoscale simulations

Plastic-bonded explosives are heterogeneous materials. Improved burn models for weak initiation relevant to accident scenarios require a better understanding of the physics associated with the formation and growth of hot spots. Since the relevant length scale is subgrain in extent, mesoscale simulations are needed to study hot spots. Mesoscale simulations require as input constitutive properties of an explosive grain. In addition, it is essential to account for physical dissipative mechanisms since hot spots represent local peaks in the fluctuations of the temperature field. Here, constitutive properties of the explosive HMX needed for mesoscale simulations are discussed and experimental data reviewed. Because some decomposition may occur during a measurement, it is difficult to account for systematic error in the data. To get a sense of the uncertainties in material parameters, it is necessary to examine all the available data. In addition, we discuss results from molecular dynamics simulations of some properties for which experimental data are lacking.
Methodology for public monitoring of total coliforms, Escherichia coli and toxicity in waterways by Canadian high school students

Abstract Public control and management of the environment and official decisions about environmental issues increasingly require public environmental monitoring by citizens. The aim of public monitoring is not to replace official monitoring. The difference is that official monitoring aims to determine if regulations are being broken, thus relying on accurate measurements obtained by court-acceptable procedures. Public monitoring, on the other hand, aims to determine if a site of concern to local citizens is a source of pollution; this requires the establishment of a pattern of pollution, which can be obtained by a variety of methods, as long as they are scientifically sound and reliable. Once such a pattern is established by the public, the official agencies can determine if regulations are being broken at the site of concern. Accessible methods for public monitoring are validated in this work by comparing the results of monitoring of a group of local urban waterway sites using simplified and inexpensive methods accessible to the public, with the results of monitoring the same sites using more expensive and modern officially accepted methods. The measurements were of total coliforms per 100 ml water sample, percent total coliforms that are Escherichia coli , and toxicity, using D. magna as endpoint. We found that high school students were able, after suitable training, to produce values for the above parameters comparable to those of an expert (G.S.) and to those using more expensive and modern officially accepted methods.
Synthesis and characterization of poly(urethane‐benzoxazine) films as novel type of polyurethane/phenolic resin composites

Poly(urethane-benzoxazine) films as novel polyurethane (PU)/phenolic resin composites were prepared by blending a benzoxazine monomer (Ba) and PU prepolymer that was synthesized from 2,4-tolylene diisocyanate (TDI) and polyethylene adipate polyol (MW ca. 1000) in 2 : 1 molar ratio. DSC of PU/Ba blend showed an exotherm with maximum at ca. 246 °C due to the ring-opening polymerization of Ba, giving phenolic OH functionalities that react with isocyanate groups in the PU prepolymer. The poly(urethane-benzoxazine) films obtained by thermal cure were transparent, with color ranging from yellow to pale wine with increase of Ba content. All the films have only one glass transition temperature (Tg ) from viscoelastic measurements, indicating no phase separation in poly(urethane-benzoxazine) due to in situ polymerization. The Tg increased with the increase of Ba content. The films containing 10 and 15% of Ba have characteristics of an elastomer, with elongation at break at 244 and 182%, respectively. These elastic films exhibit good resilience with excellent reinstating behavior. The films containing more than 20% of Ba have characteristics of plastics. The poly(urethane-benzoxazine) films showed excellent resistance to the solvents such as tetrahydrofuran, N,N-dimethyl formamide, and N-methyl-2-pyrrolidinone that easily dissolve PUs. Thermal stability of PU was greatly enhanced even with the incorporation of a small amount of Ba. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4165–4176, 2000