Miracle-dz/UniFAR-FTUs huggingface dataset:
Nanomechanics and dynamics of tip–substrate interactions

The consequences of tip–substrate interactions are investigated using large‐scale molecular dynamics simulations for a large (001) gold tip and a Ni(001) surface. The simulations reveal processes of adhesive contact formation upon approach of the tip to the substrate, tip elongation, and formation of an extended ordered neck upon retraction of the tip from contact, (111) reconstruction of the interfacial gold layers and the atomistic mechanisms of tip flattening and increase in contact area upon compression past the adhesive contact point. The hysteresis in the force versus tip to sample distance relationship, found upon approach and subsequent separation of the tip from the sample, is related to processes induced by adhesion and intermetallic bonding. The atomic‐scale mechanisms underlying the jump‐to‐contact phenomenon at small tip to surface separation (∼4.2 A) and of the inelastic processes and structural transformations involved in tip elongation, neck formation, and tip compression are discussed, and the results are compared to our earlier studies of a nickel tip interacting with a goldsurface.
EFFETS DU CADMIUM SUR LA FORMATION DU PHOSPHOGYPSE LORS DE LA PRODUCTION DE L'ACIDE PHOSPHORIQUE

Abstract La teneur maximale en cadmium atteinte dans le phosphogypse prepare selon la voie humide en utilisant une attaque sulfurique du phosphate apatitique est de l'ordre de 0.62%. A faibles concentrations en ions cadmium (inferieur a 0.26%), l'analyse physico-chimie du phosphogypse montre que le cadmium est substitue aux ions calcium dans les phases du sulfate de calcium et de la brushite. Ce qui affecte la solubilite du phosphogypse. Par contre, a fortes concentrations (au dela de 0.26%), la variation de la teneur en cadmium dans l'acide n'a d'effet ni sur la solubilite du phosphogypse ni sur le rendement en P2 O5 du fait que le cadmium qui precipite dans la phase solide se trouve dans des phases separees sous forme de CdSO4, H2 O et CdHPO4,2H2 O. Phosphoric acid manufacture by the wet process, which forms the basis of phosphate fertilizer manufacture, results in redistribution of cadmium in the phosphate ore between the phosphoric add and the waste calcium sulphate. We conclude that the maximum amoun.
Synergistic effect of pulsed corona discharges and ozonation on decolourization of methylene blue in water

The effect of O2 and O3 bubbling on decolourization of methylene blue by pulsed corona discharges in water was studied. The pulsed corona discharges were produced by charging an 80 pF capacitor with a 40 kV DC source, through a 100 MΩ resistor, and discharging it into a needle-plate type reactor at 60 Hz through a rotating spark gap switch. A 20 ml sample of 13.25 mg l-1 methylene blue in distilled water was decolourized in 120 min. Bubbling O2 at 10 ml min-1 through the discharge region reduced the decolourization time to 25 min. Bubbling O2 containing 1500 µmol O3 l-1 at 10 ml min-1 reduced the decolourization time to 8 min. The O3 was produced by fractionating input energy between a water treatment reactor and a O3 generator, i.e. no additional energy was consumed for O3 production. Under the same experimental conditions methylene blue solution in tap water was decolourized in >210 min by corona discharge in solution, in 30 min by corona discharge with O2 bubbling, and in 11 min by corona discharge with bubbling of O2 containing 1500 µmol O3 l-1.
Flammability and thermal degradation behaviors of phosphorus‐containing copolyester/BaSO4 nanocomposites

A novel phosphorus-containing copolyester (PET-co-DDP)/barium sulfate (BaSO4) nanocomposite was synthesized by in situ polymerization. The oxygen index values of the resulting nanocomposites decreased with increasing the content of BaSO4 nanoparticles, but their antidripping behaviors were improved obviously through the UL-94 test. The flammability tests based on the cone calorimetry showed that the introduction of nano-BaSO4 to the copolyester decreased remarkably the heat release rate and effective heat of combustion. The thermal oxidative decomposition behaviors of PET-co-DDP/BaSO4 nanocomposites were studied by a conventional dynamic thermogravimetric analysis in a flowing air atmosphere with a heating rate of 20°C/min. The activation energies determined from Kissinger method, Flynn-Wall-Ozawa method, and Friedman method had a same variation trend. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 564–570, 2006
Remote sensing and on-site characterization of wetlands as potential habitats for malaria vectors – A pilot study in southern Germany

Wetlands, particularly in developing countries, are common hotspots of insect-borne diseases that are a constant threat to public health, such as malaria. To help identify and characterize potential breeding grounds for mosquitoes, we utilize freely available satellite image data and software in combination with a mosquito trap system. Multispectral time-series analysis of Sentinel-2 and Landsat 5–8 satellite images of Lake Schmiechen (Swabian Alb, southern Germany), used here as a pilot and analog site for other lake and wetland areas potentially populated by malaria vector mosquitoes, reveals non-seasonal periods of flooding and drying and concomitant changes in the distribution of open shallow water. Water distribution maps are derived from spectral indices commonly used for wetland mapping (e.g., the NDWI2) and should be ground-truthed. In combination with the identification and counting of mosquitoes and the integration of other environmental parameters on-site, this approach provides a powerful tool to remotely monitor relatively small bodies and narrow networks of open shallow water that may provide habitats for mosquitoes. Combined remote sensing and on-site monitoring of potential malaria vector habitats can be implemented at low cost and with little effort in regions worldwide where the disease is established or emerging, and can be used to create or refine risk maps on small to large scales. The present approach can, moreover, complement public health programs and humanitarian efforts to fight insect-borne diseases.
Education and intercultural relations: a case study of Ghanaian and Nigerian students in Finland

International Education has gained prominence the world over. Many students migrate to different parts of the world in pursuit of further education. This phenomenon comes with its own benefits and challenges. Many tertiary institutions are now promoting “internationalization”, diversity and multiculturalism, therefore encouraging qualified international students to apply for admission into these institutions. This notwithstanding, the international students come with their own beliefs and perceptions. They initially encounter problems in their attempt to settle in the host country. This research examined intercultural relations/communication problems and challenges that international students in Finland specifically in the University of Eastern Finland faced and how they overcame them. Using thirty (30) international students from Nigeria and Ghana as sample size, the researcher obtained data through questionnaires and gathered information on their experiences and challenges. The research results indicated that majority of the respondents did not speak the Finnish language, thereby, making it very difficult to interact and socialize as well as have access to social services. Some respondents also stated challenges in adjusting to the general Finnish way of life. The data also revealed that some intercultural barriers the respondents encountered were stereotyping, prejudice, etc. Furthermore, some of the respondents stated that they misconstrued and misinterpreted some non-verbal communication symbols like body language, gestures, facial expressions etc. The challenges they experienced however, did not negatively affect their studies as the medium of instruction was English. The research also concluded with recommendations such as compulsory Finnish lessons for international students. Other recommendations included organizing more intercultural programmes to promote interaction e.g. international week, festivals, fun fare, debates, excursions and group discussions. These recommendations are crucial to dispel stereotypes, misinterpretations and other misconceptions that exist in the various cultures. This could serve as an avenue to bond and learn from each other’s cultures.
Rubidium ion hydration in ambient and supercritical water

X‐ray absorption fine structure (XAFS) measurements and analyses are presented for Rb+ in supercritical water solutions. The structure of the first hydration shell at ambient conditions is compared to that in the supercritical region at a temperature of 424 °C and pressures from 382 to 633 bar. For all reported studies, RbBr at a concentration of 0.5 molal was used. XAFS results show that there is a well‐defined hydration shell around the cation even at 424 °C but at these high temperatures the extent of hydration of the Rb cation is reduced by about 40%. A slight contraction of this first shell distance by about 0.10 A is also observed under supercritical conditions. The reduction in the number of water‐ion bonds is analogous to the reduction in the amount of water–water hydrogen bonding that has been observed by others under supercritical conditions. The reduction in waters‐of‐hydration under supercritical conditions may also be in part due to formation of contact‐ion pairs.
In Situ Study of Nanostructure and Electrical Resistance of Nanocluster Films Irradiated with Ion Beams

An in situ study is reported on the structural evolution in nanocluster films under He+ ion irradiation using an advanced helium ion microscope. The films consist of loosely interconnected nanoclusters of magnetite or iron‐magnetite (Fe‐Fe3O4) core‐shells. The nanostructure is observed to undergo dramatic changes under ion‐beam irradiation, featuring grain growth, phase transition, particle aggregation, and formation of nanowire‐like network and nanopores. Studies based on ion irradiation, thermal annealing and electron irradiation have indicated that the major structural evolution is activated by elastic nuclear collisions, while both electronic and thermal processes can play a significant role once the evolution starts. The electrical resistance of the Fe‐Fe3O4 films measured in situ exhibits a super‐exponential decay with dose. The behavior suggests that the nanocluster films possess an intrinsic merit for development of an advanced online monitor for fast neutron radiation with both high detection sensitivity and long‐term applicability, which can enhance safety measures in many nuclear operations.
The variability of times to detect growth from individual Clostridium botulinum type E endospores is differentially affected by high pressure treatments

High pressure thermal (HPT) processing is a candidate technology for the production of safe and stable food. However, little is known about the effect of HPT or high hydrostatic pressure (HHP) treatments at ambient temperature on the variability of times to detect growth from individual spores. We investigated this effect by treating Clostridium botulinum type E spores with HHP (200–600 MPa, 20°C) and HPT (600 MPa, 80°C and 800 MPa, 60°C). Our results indicate that the mean detection times increase and the frequency distribution shifts toward longer times when HHP treatment intensity is increased. HPT treatments result in a highly scattered distribution. In contrast, pressure levels ≤300 MPa decrease detection times and heterogeneity of their distribution, which could lead to an increase in the potential risk originating from C. botulinum type E spores. Data provided here could help to refine risk assessment regarding this important food intoxicator.
Water extraction as a soil‐testing procedure for phosphate

Abstract A water‐extraction procedure which is specific for a pool of P defined by a sorption model based on the Langmuir equation was evaluated in a glasshouse experiment using perennial ryegrass grown in three contrasting soils. For each of three harvests, water‐extractable P values determined at the beginning of each period of growth gave a very much better relationship with dry matter yield responses than did Olsen and Truog P values. Also, the initial water‐extraction values were as useful as the Olsen or Truog values in predicting responses over three harvests. Water extraction appears to have potential as a soil‐testing procedure for determining the P status of soils which have received fertilizer P.
Tetrafunctional Multigraft Copolymers as Novel Thermoplastic Elastomers

Tensile properties and morphology of tetrafunctional multigraft copolymers are investigated dependent on PS volume fraction and number of branch points. It is found that tetrafunctional multigraft copolymers with 22 vol % PS and seven branch points show a surprising high strain at break of about 2100%, about double that of commercial thermoplastic elastomers (TPE's) such as Kraton. With increasing number of branch points, strain at break and tensile strength increases, and strain at break is about 2300% for a sample with 10 branch points. Investigation of morphology using transmission electron microscopy indicates that a sample with 22 vol % PS has a wormlike microphase-separated structure with much lower long range order than other TPE's s such as Kraton. The multigraft copolymers of this study have two PS arms at each branch point. This, together with a large number of branch points per molecule, allows the elastic PI backbone to couple into a large number of reinforcing PS domains, resulting in huge el.
Excess Heat Capacity Surfaces for Water-Alkanol Mixtures by the UNIQUAC Model

Hydroorganic mixtures are industrial solvents that can serve as media to solubilize either water in hydrocarbon or a hydrophobic substance in water. In many cases the solubilizing capability is obtained via a homogeneous complex aqueous mixtures containing an alcohol. Since excess heat capacity, C p E , is very sensitive to structural changes in mixtures, concentration and temperature dependence of C p E have been calculated by using the UNIQUAC model for the mixtures methanol(1)-water(2), ethanol(1)-water(2), and 1-propanol(1)-water(2). The temperature-dependent parameters of the model estimated directly from C p E data at more than one different isotherm are used in the calculations. The overall deviations between the calculated and experimental data points change in the range 6.52-10.15%, which indicates the satisfactory representation of C p E data by the model for engineering calculations. The temperature range of experimental data for the mixtures is 288.15 and 308.15 K. Surfaces of reduced, apparent, and partial molar excess heat capacities are also derived. The concentration and temperature dependencies of these functions suggest the existence of transitions of microstructure in the water-rich region, qualitatively similar to micellization. The surface of these thermodynamic functions facilitates a better understanding of thermodynamic properties and association of alcohol-water mixtures over a whole or certain concentration and temperature range. Such thermodynamic surfaces may be represented satisfactorily by the UNIQUAC model at low pressures
Genesis and structural properties of alkoxide-prepared titania–silica xerogels

Titania–silica mixed oxide gels with a 1 : 4 Ti : Si molar composition were prepared from the hydrolysis of tetraethoxy orthosilicate (TEOS) and tetraisopropoxy orthotitanate (TIOT), using different amounts of water, acid or base, and hydrolysis procedure. Surface area, pore structure, and crystallinity were compared in relation to sol-gel process conditions. Gels in which the TEOS was hydrolysed using a basic medium possessed larger mesopores and correspondingly lower surface area than gels prepared with acid-hydrolysed TEOS, but were more resistant to mesopore collapse upon drying, owing to the spherically shaped silica subunits in these gels. Gels hydrolysed by a two-stage procedure, involving partial hydrolysis of TEOS in acid, followed by mixing with pure TIOT and completion of hydrolysis, are most susceptible to pore collapse upon drying, producing a completely microporous xerogel. Pore collapse did not occur when the wet-gel material was aged in slightly basic medium for several days. All gels prepared by the two-stage hydrolysis procedure remain X-ray amorphous after treatment in air at 870 K, whereas gels produced by mixing completely hydrolysed component sols show crystallization of the titania. Thermal analysis runs show water loss primarily results from weakly bound water. In general, a residual amount of unreacted alkoxy groups is present in gels prepared without a large excess of hydrolysis water. Highest residual organic amounts of 2–8 wt. % were found with the two-stage hydrolysed gels. Rutile was only detected in gels prepared in excess water, but the extent of rutile formation, as well as crystallite growth, is considerably less than in similarly prepared pure titania gels.
Principal Component Analysis of the Modified Clinical Test Ofsensory Interaction in Healthy Adult Humans

A number of mechanisms and sensory systems in humans are associated with the maintenance of balance. Diagnosis and monitoring of balance dysfunctions could be assisted by exploring deviations of data recorded from patients with comparative or reference data from healthy individuals. To this effect, principal component analysis (PCA) was applied to accelerometry obtained time domain balance data. The data were recorded from 21 healthy adults (10 males and 11 females, mean age 24.5 years, standard deviation 4.0 years, mean height 173.6 cm, standard deviation 6.8 cm, and mean weight 72.7 kg, standard deviation 9.9 kg) in the medio-lateral (ML) and anterior- posterior (AP) directions. The subjects performed tasks specified in the modified clinical test of sensory interaction on balance (mCTSIB) while an accelerometry device was attached at their lower back, in the position of the iliac crest. Eighteen-time domain measures that quantified body's displacement, velocity and acceleration were obtained and processed using PCA. Based on the observations from PCA, further investigations were carried out on the root mean square (RMS) velocity using the Bland and Altman plots and other statistical related analysis. It was observed that the anterior and posterior directions were more sensitive to the absence or presence of balance sensory (visual, somatosensory and vestibular) inputs as compared to the mediolateral (ML) direction. A greater coherence in sway information was observed in the somatosensory system as compared to the visual and vestibular systems. There was more stability in the interaction between the somatosensory and the vestibular systems as compared to that of the visual and vestibular systems. The results obtained could be helpful to clinicians in balance related analysis and diagnosis.
Poly (1-Butene)/Clay Nanocomposites: A Crystallization Study

Abstract Nanocomposites of poly (1-butene) (PB)/clay were prepared by melt intercalation. Organically modified clay was used to facilitate the melt intercalation. The effect of modified layered silicate on crystallization, spherulitic structures and polymorphism of PB was investigated. Isothermal crystallization studies clearly indicate enhancement in crystallization rate by the clay. Incorporation of layered silicate in the polymer disturbs the spherulitic morphology as evidenced by optical microscopy. The crystallization of PB in the presence of layered silicates occurs in form II, similar to pristine PB. However, the phase transformation studies reveal that the phase transformation from form II to form I at room temperature takes place faster in the case of PB nanocomposites.
New Synthetic Methodologies for Amphiphilic Multiblock Copolymers of Ethylene Glycol and Propylene Sulfide

A new one pot synthetic method has been developed for preparing amphiphilic block copolymers. The method makes use of episulfide anionic polymerization for generating symmetric or asymmetric tri- or multiblock copolymers with living mechanism. Important features of the method are (a) the use of in situ generated thiolates, which ensures reproducibility in the initiator concentration; (b) the mild character of the reactive species; therefore, also sensitive bioactive groups could be easily incorporated into the polymer structure; (c) the tolerance to impurities in the reagents and the one pot character, which allow the use of the method also by operators with limited skills in organic synthesis.
Study of Gustave Moreau's black drawings: identification of the graphic materials by Raman microspectrometry and PIXE

The identification of graphic materials with the naked eye is not always straightforward. A new collaboration with the Gustave Moreau museum in Paris offered the opportunity to test the combination of two analytical techniques in order to improve the knowledge of the materials used by this artist. The French painter Gustave Moreau (1826–98) made many monochromatic drawings on paper with black materials containing carbon such as black chalk, graphite or inks, and sometimes both materials on the same sheet. The nature of the support and that of the materials used prohibits any sampling and visual examination alone is not sufficient to identify all the materials. In order to provide a reference for the identification of the graphic technique, a first series of six drawings stored in the Gustave Moreau museum was brought to the Centre for Research and Restoration of the Museums of France for an extensive investigation. Examinations under a binocular microscope, using IR radiation, combined with PIXE analyses with the external beamline of the ion beam analysis facility and by Raman microspectrometry resulted in the identification of graphite pencil, pure graphite, reconstituted black chalk and two inks, one of which was probably a 19th century ink and made with logwood. The analysis of this first set of drawings enabled us to determine the graphic techniques of 10 other drawings by simple visual observation. Copyright © 2004 John Wiley & Sons, Ltd.
Review of deposition monitoring methods

Deposition monitoring may generally serve at least one of the following purposes: (a) determining ecosystems at risk, (b) evaluating temporal and spatial trends, (c) developing numerical models, or (d) estimating deposition effects. In this paper, an overview of available knowledge about monitoring methods is given. Furthermore, it is tried to illustrate the (dis)agreement between results obtained using different methods. It might be concluded that throughfall, micro meteorological methods (supplemented/supported by inference) and watershed balance methods (S saturated systems) yield similar estimates of the annual mean total deposition of sulphur, within generally acceptable uncertainly limits (∼ 30%). A larger uncertainty exists to estimate reduced or oxidized nitrogen and base cation fluxes. It is clear that for individual ecosystems deposition in general, and dry deposition in particular, can still not be quantified with sufficient accuracy. The various methods have different advantages and drawbacks and the choice of a certain method for estimation of the flux of a specific pollutant to a specific ecosystem may in many cases depend on the purpose of the study and on requirements on accuracy and costs. DOI: 10.1034/j.1600-0889.1994. t01-1-00001.x