Miracle-dz/UniFAR-FTUs huggingface dataset:
Effets de la terminaison de l’α-alumine sur le comportement au mouillage du zinc

Le procede de galvanisation a chaud se compose d’un recuit continu suivi d’une immersion de la bande d’acier dans un bain de zinc afin de lui conferer une protection contre la corrosion. Au cours de l’etape de recuit de recristallisation des nouveaux aciers, dits a « haute limite elastique », les elements d’addition, tel que l’aluminium, segregent et diffusent en surface ou ils forment des ilots voire des films superficiels qui, mal mouilles par le zinc liquide, nuisent a la qualite du produit final. Dans ce cadre, l’etude s’est attachee d’une part a caracteriser l’oxydation selective d’alliages binaires Fe-Al et d’autre part, dans le cas modele de l’α-alumine (0001), a determiner les effets de la terminaison de surface sur l’energie d’adhesion du zinc, a l’aide d’une approche combinant simulations numeriques ab initio (theorie de la fonctionnelle de la densite) et experiences sous ultra-vide (reflectivite UV-visible, photoemission et desorption thermique). A l’issu de recuits calques sur les conditions industrielles les alliages binaires Fe-Al (1,5 et 8% pds.) presentent en surface une couche couvrante d’γ-alumine de plusieurs nanometres d’epaisseur. Une entree du flux de gaz focalisee sur l’echantillon aboutit a une croissance vermiculaire des grains d’alumine alors qu’un flux de gaz homogene engendre une croissance plus structuree qui montre que l’approche modele Zn/α-alumine (0001) est pertinente.Les simulations numeriques faites aux premiers stades du depot, ont montre que, le zinc interagit faiblement avec la surface stœchiometrique (1x1), ce qui confirme l’experience. Experience et calcul convergent sur la valeur de ≈ 0,5 eV de l’energie d’adsorption. Par contre, un exces de charge de surface peut considerablement renforcer l’adsorption. Deux mecanismes ont ete identifies et decrits en terme de stabilite thermodynamique, en fonction des conditions environnementales (pression, temperature) : (i) une sous-stœchiometrie surfacique en Al, telle que presente sur la terminaison polaire, (ii) un exces de groupements hydroxyles de surfaces, issus de la dissociation de l’eau, operationnel aussi bien sur la terminaison polaire que non-polaire de l’alumine. En parallele avec l’experience, la simulation montre que le zinc est capable d’interagir fortement avec la surface en en deplacant l’hydrogene des groupements hydroxyles de surface. L’energie d’adsorption du zinc ainsi adsorbe, evaluee a 7 eV par le calcul, est du meme ordre que la valeur experimentale de 3,5 eV. L’etude etendue a plusieurs metaux de transition a permis d’identifier le titane comme element montrant l’interaction la plus forte avec l’alumine et qu’un enrichissement en titane de la surface d’alumine peut fortement ameliorer l’adhesion du zinc.
Inter-subband scattering in a 2D electron gas

A new technique, using the absolute amplitude of the low-field Shubnikov-de Haas oscillations, is presented which allows the direct measurement of inter-subband scattering in 2D heterojunction structures. When applied to a heterojunction with two subbands occupied the technique is used to show that inter-subband scattering is independent of temperature between 1 and 4 K. In agreement with previous reports frequency and amplitude intermodulation, which increases with temperature, is also observed. This is attributed to mixing, by thermal or impurity damping, between the two sets of oscillations in the Fermi energy. This explanation is supported by a model calculation which reproduces the features of the experimental results.
Direct observation of the potential distribution within organic light emitting diodes under operation

We show the first direct measurement of the potential distribution within organic light emitting diodes (OLEDs) under operation and hereby confirm existing hypotheses about charge transport and accumulation in the layer stack. Using a focused ion beam to mill holes in the diodes we gain access to the cross section of the devices and explore the spatially resolved potential distribution in situ by scanning Kelvin probe microscopy under different bias conditions. In bilayer OLEDs consisting of tris(hydroxyquinolinato) aluminum (Alq3)/N, N ′‐bis(naphthalene‐1‐yl)‐N,N ′‐bis(phenyl) benzidine (NPB) the potential exclusively drops across the Alq3 layer for applied bias between onset voltage and a given transition voltage. These findings are consistent with previously performed capacitance–voltage measurements. The behavior can be attributed to charge accumulation at the interface between the different organic materials. Furthermore, we show the potential distribution of devices with different cathode structures and degraded devices to identify the cathode interface as main culprit for decreased performance. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)
Comparison of intermolecular interactions in two phases of MeNSOF2

Abstract MeNSOF2 was crystallised by laser-assisted zone refinement at 150 K. The structure obtained by X-ray diffraction initially on cooling to 140 K was triclinic, P-̄, but this transformed slowly to a second phase, which was monoclinic C2/c. Bond distances and angles are similar to equivalent interactions in (MeN)2 SF2 and SO2 F2. Intermolecular interactions in both phases are dominated by dispersion, though electrostatics are also important in all the most energetic contacts. Though no interatomic contacts fall within the sums of van der Waals radii of the contacting atoms, PIXEL calculations indicate that some intermolecular energies are similar to medium-strength hydrogen bonds. The monoclinic phase is denser than the triclinic phase, having stronger dispersion interactions. PIXEL and DFT calculations indicate that the two phases are energetically very finely balanced, but phase I becomes competitive at higher temperature on account of the entropy advantage of its ‘looser’ structure. DFT phonon energy calculations suggest that the mechanism of the transition may involve coupling between acoustic and low energy optical phonons.
On the folding and conformation of peptides and the development of novel methods for their study

ON THE FOLDING AND CONFORMATION OF PEPTIDES AND THE DEVELOPMENT OF NOVEL METHODS FOR THEIR STUDY Matthias M. Waegele Feng Gai Proteins are polymers, whose complex chemistry and physics, in the course of evolution, permitted their recruitment for immensely diverse functions in the biological machinery. Therefore, the study of protein conformational behavior and interactions of proteins with other entities of the intraand extra-cellular milieu is of great interest. In this Thesis, we do not only quantitatively study the folding of peptide and protein systems using well-established spectroscopic techniques, but also, in recognizing the limits of existing experimental techniques, develop novel methods for studying protein folding, protein-protein and protein-membrane interactions. In the first part of this Thesis, we are concerned with studying the folding process under various conditions using small peptides or proteins as model systems that allow a tractable, quantitative description of the order-disorder transition. Employing a combined site-directed mutagenesis/temperature-jump kinetics approach, we elucidated the folding mechanism of a helical hairpin, which is an important intermediate in protein folding reactions. We further considered how the folding kinetics of such model peptides and proteins are altered in the presence of high concentrations of
Preparation and Characterization of Microfiltration Membrane Embedded with Silver Nano-Particles

The microfiltration 0.2 µm Cellulose Acetate (CA) membrane was modified by embedding antibacterial silver nano-particles in the membrane pores. This novel technique was developed to enhance the capability of the microfiltration membrane for removing microorganism including bacteria. The prepared membrane was characterized using Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectroscopy (EDS), water contact angle measurement and Differential Scanning Calorimetry (DSC). Membrane performance was elucidated by flux and rejection measurements using water samples from the pond of a public recreational park in Tehran. For rejection capability of the membrane, the availability of filament and c-shaped species of the phyla Actinobacteria and Spirochetas in the permeate side of the membrane was estimated. Contrary to virgin membrane, the modified membrane was able to remove 100% of Actinobacteria and Spirochetas species from the infected water. Moreover, the wettability of the modified membrane was remarkably changed leading to higher water flux. A potential application of the modified Ag-CA membrane is "sterile filtration" of temperature sensitive fluids.
Determination of the Li–Hg Intermolecular Potential from Molecular‐Beam Scattering Measurements

The experimental differential‐cross‐section extrema data of Groblicki and Bernstein have been analyzed and yield a family of potential parameters. These results were combined with the inferences obtainable from the glory extrema in the total cross sections of Rothe and Veneklasen to deduce a potential compatible with both experiments. The resulting potential is found to have a well depth e = 1.70 × 10−13erg ± 3% with a size parameter rm = 3.02 A ± 3%. The long‐range coefficient is C6 = 4.4 × 10−58erg·cm6 ± 60%.
Measurement of the Effective Density of Both Spherical Aggregated and Ordered Porous Aerosol Particles Using Mobility- and Mass-Analyzers

Online measurement of the effective density of both spherical aggregated and ordered porous particles was systematically investigated using differential mobility analyzer-aerosol particle mass analyzer (DMA-APM). Effective density was determined based on the relationship between electric mobility and mass; mobility and mass were measured using DMA and APM, respectively. The particles were prepared using a spray-drying method; a colloidal suspension of silica nanoparticles was used as the precursor, and both nanoparticles and polystyrene latex (PSL) particles were used to generate the aggregated and ordered porous particles. The effective density of aggregated particles decreased from 1916.0 to 1565.2 kg/m3 when the primary particle size was increased from 6 to 100 nm. The effects of pore size and fraction, which were controlled by PSL particle concentration and size, on the effective density of ordered porous particles were also investigated. The effective density of the ordered porous particles decreased from 922.2 to 682.3 kg/m3 with increasing the porosity from 58.1 to 69.0%, and negligibly affected by individual pore size in a particle. The accuracy of the effective density measurement based on the DMA-APM was greater than 97%. In addition, this method effectively determined particle porosity, as compared by the light-scattering method, with a difference of less than 5% between methods.
Characterization and Kinetic study of PAH–degrading Sphingopyxis ummariensis bacteria isolated from a petrochemical wastewater treatment plant

The expansion of a microbial bank for the degradation of polycyclic aromatic hydrocarbons (PAHs) is crucial for removal of these persistent pollutants. In this study, five gram-negative, aerobic, non-fermentative bacterial strains (III-R3, IV-P11, IV-P13, IV-R13, and V-P18) were isolated from the activated sludge of a petrochemical wastewater treatment plant using enrichment pro­ tocol based on phenanthrene. The isolates were capable of utilizing phenanthrene, anthracene, and pyrene as a sole carbon and energy source in an aerobic batch aqueous system. The PAHs biodegradation yields were evaluated by gas chromatography and the bacterial isolates were identified using the 16S rRNA sequencing method. A first-order kinetic model provided the best fit to the phenanthrene degradation profiles with a correlation coefficient value of 0.95-0.98. The phenanthrene biodegradation rate constants and half-lives were measured at the range 0.653--Q.878 day-' and 0.79-1.06 day, respectively. Lower values of Anthracene degradation re­ sulted with the isolates of the current study, while a relatively high percentage of the removal of Pyrene was obtained by some of the isolates. The data obtained in this study shows that bacterial isolates have degradation preference over Mycobacterium sp. and Pseudomonas aeruginosa; and they are comparable with Pseudomonas stutzeri, Sphingomonas sp. , and microbial consortium applied by other researchers. Analysis of the 16S rDNA gene sequence, when compared with the GenBank, indicates that all the strains belong to the genus Sphingopyxis with the nearest type strain being Sphingopyxis ummariensis Ul2 (MTCC 8591T). It is the first time that Sphingopyxis ummariensis is reported for its capability in the degradation of PAHs.
ESTIMATION OF GIBBS FREE-ENERGIES OF FORMATION FOR POLYCHLORINATED-BIPHENYLS

Gibbs free energies of formation for gas, subcooled liquid, and aqueous solution phases were estimated for all 209 polychlorinated biphenyl (PCB) congeners at 298.15 K and 100 000 Pa. A literature search was conducted to locate experimental data or predicted data for PCBs. Where other data were not available, the standard-state enthalpies of formation of the gas and absolute standard-state entropies of the gas were estimated using the NIST Structures and Properties Database and Estimation Program based on Benson's group additivity method. Resultant Gibbs free energies of formation in aqueous solution, as well as all intermediate quantities used in their calculation, are tabulated. Implications of the data relative to dechlorination are briefly discussed.
Non-portability of Algorithmic Fairness in India

Conventional algorithmic fairness is Western in its sub-groups, values, and optimizations. In this paper, we ask how portable the assumptions of this largely Western take on algorithmic fairness are to a different geo-cultural context such as India. Based on 36 expert interviews with Indian scholars, and an analysis of emerging algorithmic deployments in India, we identify three clusters of challenges that engulf the large distance between machine learning models and oppressed communities in India. We argue that a mere translation of technical fairness work to Indian subgroups may serve only as a window dressing, and instead, call for a collective re-imagining of Fair-ML, by re-contextualising data and models, empowering oppressed communities, and more importantly, enabling ecosystems.
Effect of polyaniline‐graphene nanosheets modified cathode on the performance of sediment microbial fuel cell

BACKGROUND The limitation on output power is a great challenge for the practical application of sediment microbial fuel cells (SMFC). One of the effective strategies to overcome this problem is to develop better-performing cathodes. RESULTS Polyaniline (PANI)-graphene nanosheets (GNS) modified cathodes were fabricated and applied as the cathodes of SMFCs to improve their electricity generation capacity. PANI-GNS cathodes were fabricated through situ-polymerization of aniline in a solution containing homogeneously dispersed GNS. The mass ratio between aniline and GNS in the polymerized solution was the key factor controlling the properties of the modified cathode and the optimum ratio was 9:1. Because of the outstanding electrical conductivity of GNS, PANI-GNS cathodes outperform the control (blank) and PANI cathodes. The PANI-GNS0.1-SMFC exhibited the highest output voltage of 640 mV, 5 times that of the blank SMFC; the maximum power density was improved from 0.85 mW m-2 with the blank SMFC to 99 mW m-2 of the optimal PANI-GNS0.1-SMFC. CONCLUSIONS This study provides a simple electrode modifying method to enable an as-synthesized PANI-GNS cathode to dramatically promote the performance of an SMFC. © 2013 Society of Chemical Industry
Buffer gas cooled beams and cold molecular collisions

The vast majority of techniques for cooling, manipulating, and trapping molecules demonstrated to date rely on specific and unusual features of the molecular species being studied. We present here a suite of tools for cooling a wide variety of molecules, and for creating bright, cold, and slow molecular beams. The buffer gas techniques used depend only on very general qualities of the molecule and we demonstrate them to be widely applicable. Current and future applications to studies of new physics and chemistry are presented.
Molecular structure of the uranyl mineral zippeite – An XRD, SEM and Raman spectroscopic study

Raman spectra at 298 and 77 K and infrared spectra of the uranyl sulfate mineral zippeite, K2[(UO2)6(SO4)3O(OH)6]. 4 H2O, were studied. Observed bands were tentatively attributed to the (UO2)2+ and (SO4)2- stretching and bending vibrations, the OH stretching vibrations of water molecules and hydroxyls, H2O bending vibrations and libration modes, and ￤ U-OH bending vibrations. Empirical relations were used for calculation of U-O bond lengths in uranyl R = f(￮3 or ￮1 (UO2)2+) A. This was found in agreement with U-O bond lengths from the single crystal structure analysis. The number of observed bands supports the conclusion from single crystal structure analysis that at least two symmetrically distinct U6+ (in uranyl) and S6+ (in sulfate), and water molecules and hydroxyls may be present in the zippeite crystal structure. Some O-H…O bond lengths were attributed to the hydrogen-bonding network in zippeite crystal structure.
Surface Binding Properties of Tetraoctylammonium Bromide-Capped Gold Nanoparticles

Surface interaction of gold nanoparticles with solvents and functionalized organic molecules is probed using the changes in the surface plasmon absorption band. A red shift in the surface plasmon band is observed with increase in solvent dielectric constant for solvents that do not complex with metal surface. A plot of the square of the observed position of the surface plasmon bands of Au nanoparticles in these solvents as a function of medium dielectric function shows a linear dependence. Interestingly, the surface plasmon band position remains unaffected in polar solvents (with nonbonding electrons) and is attributed to the direct interaction of these solvents with the gold surface. Binding of gold nanoparticles with organic molecules containing functional groups such as −SCN or −NH2 were found to dampen the surface plasmon bands. Binding of phenyl isothiocynate (PITC) and 15N-labeled benzylamine to gold nanoparticles was probed using NMR techniques, and in both cases, two sets of signals were observed,.
Phenotypic variation and polymorphism confirmed among white-bellied swiftlets of the Collocalia esculenta group (Apodidae, Collocaliini) by mitochondrial and nuclear DNA evidence

Summary. Among white-bellied glossy swiftlets of the Collocalia group, A. R. Wallace was first to recognise the Makassar Strait, separating Borneo and Sulawesi, as a geographical barrier between different phenotypes: plain-tailed to the west and spot-tailed to the east. Other morphological characters used to define species within the group have been blue or green gloss to the dorsal plumage, and the presence or absence of a single minute tufted feather on the hallux. The value of these characters as taxonomic markers is now known to be unreliable due to the discovery of phenotypically mixed populations east of the Makassar Strait, from North Maluku province, I ndonesia, through Papua New Guinea to New Ireland. We combine field observations of plumage characters with genetic evidence to establish taxonomy of Collocalia group swiftlets. Sequencing specific mitochondrial genes (Cytb and ND2), the nuclear-encoded Fib gene, and a subset of mitochondrial genomes provided data for phylogenetic analysis. Genetic divergence of c.4. 7% is observed between two Collocalia clades either side of the Makassar Strait: the plain-tailed C. affinis cyanoptila sampled at Fraser's Hill, Peninsular Malaysia, and a phenotypically mixed population of C. esculenta spilura from North Maluku, Indonesia. Each population formed high-affinity genetic clades, within which divergence was <0.5%. These findings are consistent with geographic but not phenotypic separation between populations. We therefore conclude taxonomy based on these plumage features in glossy swiftlets of the Collocaliini is unreliable.
Stability of Curcumin Microencapsulated by Spray and Freeze Drying in Binary and Ternary Matrices of Maltodextrin, Gum Arabic and Modified Starch

Curcumin yellow dye is considered as an antioxidant, susceptible to light and oxidative degradation. Microencapsulation improves its stability and facilitates its use. This work aimed to investigate the effects of different formulation wall materials (gum arabic, a binary mixture of maltodextrin and modified starch, and a ternary mixture of gum arabic, maltodextrin and modified starch) and different drying methods (for spray and lyophilization) on the stability of microcapsules of turmeric oleoresin. The drying method affected retention curcumin powder in the drying process and storage of the microcapsules under incident light. Curcumin retention during lyophilization was greater than spray drying, but showed the opposite behavior during storage; spray-dried capsules had a higher retention of curcumin after 8 weeks under light exposure. As a result, the ternary mixture of gum arabic, modified starch and maltodextrin was more effective to prevent loss of curcumin and color changes in the microcapsules. Practical Applications The main function of turmeric oleoresin is to give color and tempered aroma in certain foods such as pickles and mustard. The knowledge of encapsulation techniques allows the control of the bioactive components, the release time and dosage of turmeric oleoresin in the structure of the food. Moreover, the encapsulation of oleoresin helps to reduce oxidation process by exposure to the environment, increasing the shelf life and the solubility. The results of analysis of this work lead to the use of bioactive components for implementation in similar products, thereby improving their stability.