Miracle-dz/UniFAR-FTUs huggingface dataset:
A safe sonochemical route to iron, cobalt and nickel monoarsenides

In this paper, we report a safe method for the preparation of transition metal arsenides. At room temperature, well-crystallized and monodispersed arsenides particles were successfully obtained under high-intensity ultrasonic irradiation for 4 h from the reaction of transition metal chlorides, arsenic (which is the least toxic arsenic feedstock) and zinc in ethanol. Characterization by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), electron diffraction (ED), and X-ray photoelectron spectroscopy (XPS) shows that the product powders consist of nanosize particles. The ultrasonic irradiation and the solvent are both important in the formation of the product.
Impact of land use changes on the hydrological properties of volcanic ash soils in South Ecuador

Abstract. The effect of land use on the water retention capacity of Umbric Andosols in south Ecuador was studied. The objective was to acquire a better insight into the hydrological processes of the ecosystem and the role of the soil, in order to assess the impact of changing soil properties due to land use change on the hydrology of the high Andes region. Field data on the water retention capacity at wilting point of Umbric Andosols were collected for both cultivated field conditions and original bush vegetation. The pH in water and in NaF, texture, organic matter content and dry bulk density were measured to show which physicochemical soil characteristics are responsible for the water retention of the Umbric Andosols and for the irreversible loss in water retention due to air drying. Organic matter content appears to be very important and certainly more important than allophane clay content. Water retention of the organic litter layer was calculated to be 16 mm, this would be lost when vegetation was cleared and the land cultivated.
The kinetics of condensation and evaporation of H2O from pure ice in the range 173–223 K: a quartz crystal microbalance study

The kinetics of evaporation and condensation on ice condensed from the vapor phase at 190 K has been studied in the range 173–223 K using a suitably calibrated quartz crystal microbalance that was put inside a vacuum chamber that could be used either as a molecular or a stirred flow reactor, depending on the measured pumping speed. The Arrhenius representation of the zero order evaporative flux Jev (molecule cm−2 s−1) displays a discontinuity at 193 ± 2 K that could be observed owing to the degree of precision of the present measurements. For 223 > T > 193 K, Jev = (1.6 ± 0.7) × 1028exp((−10.2 ± 0.5)/RT) molecule cm−2 s−1and for 173 < T < 193 K, Jev = (2.2 ± 0.9) × 1030exp((−12.0 ± 0.5)/RT) molecule cm−2 s−1 where R = 1.987 × 10−3 kcal mol−1 K−1. The corresponding measured rate constant kcond for H2O condensation on ice satisfies the known vapor pressure Peq (H2O) together with Jev thereby affording thermochemical closure of the kinetics which results in the heat of sublimation ΔHsubl0 = 11.7 ± 0.6 and 12.3 ± 0.5 kcal mol−1 from the above high and low T-range, respectively. Jev is significantly lower than the maximum theoretically allowed value throughout the T-range in agreement with an uptake coefficient for H2O on ice that is significantly smaller than unity. In addition, the negative temperature dependence of kcond or γ reveals a precursor-mediated adsorption/desorption process for the H2O/ice system. The increased evaporative lifetime of pure ice may be important under atmospheric conditions.
Study of Salinity Tolerance in Rapeseed

Abstract Eight diverse Brassica napus genotypes and their 28 F1s were evaluated in nonsaline and saline environments in sand culture. Combined analysis based on two salinity levels revealed significant salinity-level effects for shoot dry weight, plant height, root length, and ions in shoot tissues, including potassium (K), sodium (Na), Ca/Na, and K/Na. Salinity had no significant effect on shoot calcium (Ca) concentration. Stress intensity (SI) estimates, its larger values indicating the more severe stress intensities, were high for all studied traits except for root length, Ca, and Na. The mean of Na in a saline environment was more than seven times the mean in a nonsaline environment, therefore SI was not calculated for this parameter. Low estimates of SI for root length and Ca indicated the effects of a saline environment for these two traits were less than for the other traits. Significant interactions of genotype and salinity levels were observed for all studied traits. The results of factor analysis based on minimum eigenvalue revealed two factors for eight studied traits in a saline environment. Factor one was detected as a nutritional trait in which Ca, K, Ca/Na, and K/Na had a high coefficients factor loading. Factor two was detected as morphological traits. The results of factor analysis indicated that selection for nutritional traits should be more efficient than selection for morphological traits and, specifically, that selection based on K and K/Na should be more efficient than Ca and Ca/Na. Significant positive correlations were found between shoot dry weight and other traits, including Ca, K, Ca/Na, and K/Na in a saline environment; therefore, these ion relations can be used as good selection criteria for improving shoot dry weight. On the basis of low estimates of the tolerance index (TOL) for shoot dry weight (its large value represents more sensitivity to stress), it was concluded that the genotypes including BL2, Ceres, Shiralee, Falcon × BL2, PF7045/91 × Ceres, and BL2 × Ceres had suitable salinity tolerance in early stages of growth.
ANTIOXIDANT POTENTIAL OF SOME SPECIES OF THE GENUS Bomarea (ALSTROEMERIACEAE)

This work evaluated the antioxidant activity of ethanol extracts from 11 species of the genus Bomarea (Alstroemeriaceae) by means of two in vitro methods. Values of CE50 between 51 and 333 μg/mL were obtained for DPPH the test, and the highest activity levels were found for B. glaucescens, B. setacea, B. pardina and B. euryantha, which presented a similar CE50 or lower than the reference used, silymarin (70.6 μg/mL). Likewise, the TBARS method showed that the maximum inhibition of lipid peroxidation of the linoleic acid was produced by B. hirsuta (malondialdehyde = 0.429 μM), followed by B. bredemeyerana (0.474 μM), B. callejasiana (0.479 μM), B. euryantha (0.489 μM), B. glaberrima (0.497 μM), and B. setacea (0.500 μM). Additionally, the concentration of phenol compounds was evaluated by the Folin-Ciocalteau method, finding that B. setacea presented the highest content of these (159.75 gallic acid equivalents/mg of extract). Bomarea setacea showed the highest antioxidant properties demonstrated by its free-radical scavenging and significant inhibition capacity of the oxidation of linoleic acid.
Imaging the isotope effects in the ground state reaction of Cl CH4 and CD4

The ground state reactions of Cl + CH4 and CD4 were studied in a crossed-beam experiment, in which the ground state methyl products were probed using a time-sliced velocity imaging technique. By taking the images over the energy range of chemical significance - from reaction threshold to about 10 kcal/mol, the reactive excitation functions as well as the dependences of product angular distributions and of the energy disposals on initial collision energies were obtained. Comparing the dynamical attributes of the two isotopic reactions revealed an interesting isotope effect in product angular distributions. The previous reduced-dimensional quantum scattering calculations of Yu and Nyman appear to reproduce this isotope effect rather well. Yet, a physical understanding of its origin awaits further theoretical investigations.
Preparation and properties of photocurable unsaturated oligoester acrylourethanes

Syntheses of several photocurable resins and their properties before and after photocuring are investigated. Unsaturated oligoester acrylourethanes (IIIa–IIId) are prepared by addition reaction between four types of hydroxy-terminate unsaturated oligoesters (Ia–Id) and intermediate of adduct II. The former is prepared by addition-condensation reaction of glycols and maleic anhydride, while the latter is prepared from 2,4-TDI and equivalent HEMA by addition reaction in the presence of stannous octoate with THF as solvent. From the decrease of NCOs characteristic absorption peak at 2250 cm−1 of IR spectrum, the conversions of the reaction of 2,4-TDI with HEMA and hydroxy-terminated unsaturated oligoesters were calculated. The unsaturated photocurable resins are compared with saturated oligomers (obtained by replacing maleic anhydride with succinic anhydride) with regard to curing rates and mechanical properties. Properties of pure oligomers are determined both before and after hardening. If added with reactive monomers, the oligomers thus cured are found to possess better properties than otherwise. Among the monomers, HEMA proves to be especially helpful in the increase of mechanical properties. Above all, combined use of IIIb oligomer and HEMA serves the best purpose for metal coating.
Simultaneous 2nd order derivative spectrophotometric determination of sorbic and benzoic acids in soft drinks

Abstract A method is developed for the simultaneous 2nd order spectrophotometric determination of 1 to 7 μg. mL−1 of each of benzoic and sorbic acids in non vegetal soft drinks, using a blank prepared from the same soft drink to be analyzed in order to avoid the interferece from other additives and colouring matter present.
Dense plasma formation on the surface of a ferroelectric induced by a driving pulse with a fast fall time

Experimental results are presented of dense plasma formation on the surface of a BaTi-based ferroelectric sample during the fall time of a driving pulse. A negative or positive driving pulse (⩽14 kV), with a slow rise time (∼450 ns) and a fast fall time (40–200 ns), was applied to the rear electrode of the ferroelectric. It was found by different electrical, optical, and spectroscopic diagnostics that this method allows one to form a plasma with a larger density (∼3×1013 cm−3) as compared with that formed by a driving pulse with a fast rise time (⩽4×1012 cm−3). It was shown that the shorter the fall time of the driving pulse the more intense plasma formation occurs. The most uniform and dense plasma formation occurs with a positive driving pulse. In addition, it was found that the shorter the fall time of the positive driving pulse the larger are the current amplitude, the energy, and the divergence of the emitted electrons. The obtained results are discussed in terms of the surface plasma formation and t.
Biogenic iron compounds: XRD, Mossbauer and FTIR study

AbstractMaterials based on biogenic iron oxides, which are a product of the metabolic activities of the neutrophilic iron-oxidizing bacteria (NIOB) from Sphaerotilus-Leptothrix group, were investigated. Natural microbial probes were collected from freshwater flow from Vitosha Mountain (Bulgaria) and cultivated under laboratory conditions in respect to select suitable cultures and conditions (nutrition media) for biomaterial accumulation of biogenic oxides. Samples were studied by physicochemical methods: X-ray diffraction, Mossbauer spectroscopy and IR spectroscopy. Their phase composition and physicochemical properties were obtained. Presence of both amorphous and crystal phase (ultra- and highly dispersed particles) was proved. Iron-containing compound in the natural biomass consists of α-FeOOH. The cultivated materials have more complex composition with iron-containing ingredients as α-FeOOH, Γ-FeOOH, Γ-Fe2O3 and Fe3O4. The sample of natural biomass was tested in reaction of CO oxidation and it showed potential to be used as catalyst support.
Study of n-hexane adsorption in MCM-41 mesoporous materials: a scaling effect approach of capillary condensation processes

The adsorption of hexane on mesoporous MCM-41 materials having different pore sizes has been studied by thermodynamic means. Additional information about their textural properties has been found using the BET model and by tracing comparison plots. Extremely low CBET parameters have been found, confirming the very low affinity of alkanes for siliceous surfaces while comparison plots evidenced true mesoporous materials. The adsorbate-adsorbent interactions have been derived from the isosteric method. A correlation between the heat of condensation and the pore size has been demonstrated and is discussed. The enthalpic contribution of the liquid–gas interface to the overall process has been derived and precisely matches the difference between the enthalpy of condensation in the bulk and the enthalpy condensation in mesopores as large as 10 nm.
Effect of dimethyl sulfoxide on drug permeation through human skin

The effect of the presence of dimethyl sulfoxide (in admixture with water) on the sorption and permeation rate of scopolamine base in human skin in vitro has been measured as a function of drug concentration in aqueous solution. The equilibrium sorption of scopolamine by skin from solution appears to be unaffected by the presence of even high concentrations of dimethyl sulfoxide in the solution phase. In the absence of a transdermal gradient of DMSO (or water), the permeability of skin to scopolamine in the presence of DMSO is about twofold higher than in its absence, suggesting that the diffusivity of scopolamine in the stratum corneum is somewhat elevated by the solvating action of DMSO. When, however, a gradient of DMSO concentration is impressed across the skin (irrespective of whether that gradient is of the same or opposite sign to that of the drug), the permeability of the skin to scopolamine is increased by one to two orders of magnitude. Microscopic examination of the skin subjected to such treatment reveals marked swelling, distortion, and intercellular delamination of the stratum corneum, which is only partially reversible following complete extraction with water. These effects are believed due to development of very high osmotic stresses produced within the stratum corneum, as both water and DMSO are transported into the tissue.
Chiral arene hydrates of naphthalene: enzymatic and chemical syntheses

Bacterial metabolism of the dihydronaphthalenes 1 or 3 using cultures of Pseudomonas putida UV4 yielded the arene hydrates of naphthalene 2 or a mixture of 4 and 5 respectively; these arene hydrates have also been obtained in homochiral form either by synthesis from enantiomerically pure alcohols 10 and 12 and arene oxide 11 precursors or by chiral stationary phase HPLC separation of arene hydrate enantiomers.
Mechanics of generalized continua: construction by homogenizaton

La mecanique des milieux continus generalises fournit des outils pour decrire les effets d'echelle que presentent certains materiaux heterogenes. Cependant les liens entre les nouveaux degres de liberte que certains de ces milieux introduisent et la microstructure ne sont clairement etablis que pour quelques cas extremes (cristaux liquides.). Dans ce travail, on essaie de construire un milieu de Cosserat homogene equivalent a un milieu classique micro-heterogene, par des methodes d'homogeneisation generalisees. Ces techniques permettent alors de rendre compte des champs de contraintes et de deformation dans un materiau heterogene sollicite de telle sorte que la taille de l'element de volume representatif ne soit pas negligeable devant la longueur d'onde des sollicitations.
Effets des toxines de Bacillus anthracis sur le cytosquelette des cellules immunitaires : implication sur la phagocytose et les fonctions immunitaires

Bacillus anthracis, agent de la maladie du charbon, est aussi un agent majeur de la menace biologique. Sa virulence est liee a deux principaux facteurs : une capsule et deux toxines, la toxine oedemateuse (ET = EF + PA) et la toxine letale (LT = LF + PA). EF est une adenylate cyclase, calcium et calmoduline dependante, produisant une elevation de la concentration en AMPc intracellulaire tandis que LF est une metalloprotease a zinc clivant la majorite des Mitogen Activated Protein Kinase Kinases. Les toxines jouent un role central dans la pathogenie de la maladie du charbon et dans la deregulation des fonctions des cellules du systeme immunitaire. Le cytosquelette d'actine participe activement aux fonctions de phagocytose et de migration des macrophages et des cellules dendritiques.Cependant, peu d'etudes analysent l'implication du cytosquelette d'actine des cellules immunitaires dans la physiopathologie des toxines. ET induit une retraction temps-dependant des cellules dendritiques et des macrophages normalises sur des micropatterns de fibronectine, s'accompagnant d'une depolymerisation de l'actine et d'une perte des points d'ancrage des cellules dendritiques. Precocement, ET active la cofiline par l'activation de la voie de signalisation AMPc – PKA – Proteines phosphatases. Malgre ces alterations du cytosquelette d'actine, ET n'induit pas de modification des capacites phagocytaires des cellules dendritiques, a l'exception d'une deregulation de la maturation des phagosomes. ET conduit egalement a une augmentation de la migration des cellules dendritiques in vitro par activation et expression de CCR7 et CXCR4 a la surface des cellules dendritiques.A l'inverse, LT conduit a un etalement temps-dependant des cellules dendritiques normalisees, accompagne d'une deregulation de la dynamique de l'actine provoquant des regroupements anormaux d'actine filament. LT active les myosines phosphatases via la voie RhoA-ROCK pour dephosphoryler les myosines II. A la difference de ET, LT inhibe les capacites phagocytaires des cellules dendritiques mais ne conduit pas a une modification de la migration des cellules dendritiques in vitro.
Fractionation of heavy metals in contaminated soils surrounding non-ferrous metals smelting area in the North China Plain

Abstract The accumulation of heavy metals in soil is a serious environmental problem. The risk of metals in soil is associated critically with their species. Operationally determined speciation analysis of Cr, Mn, Ni, Cu, Zn, Sb, Cd and Pb was carried out in the area of non-ferrous metals-smelting in the North China Plain, using inductively coupled plasma-mass spectroscopy after sequential chemical extraction. The average potential mobility fraction was calculated. The average potential mobility of the metals had the following order: Cd(44.7%) > Pb(29.6%) > Mn(14.8%) > Zn(12.5%) > Cu(5.9%) > Sb(5.0%) > Ni(2.1%) > Cr(0.8%). It is concluded that there is a distinct spatial heterogeneity in the concentration of heavy metals in the studied area. The results indicate that the polluting heavy metals, in particular Cd and Pb, have high potential mobility.
Cooperativity in binding of proteins to DNA

Three different, linear, three-site binding models are presented for the binding of proteins, such as a repressor, to DNA. The first model assumes that the DNA is rigid and all correlations between the ligands are due to direct ligand–ligand interactions. In the second and third models conformational changes in the DNA are induced by the binding process. In these models we find both direct and indirect correlations between the ligands. Examination of the indirect correlation reveals two characteristic features that, in general, are negligible in the direct correlation. (1) Long range correlation, between nonadjacent sites. (2) Nonadditivity of the triplet correlations. It is shown that these two features cannot be neglected in the indirect correlations. The arguments for explaining these features are similar to those which explain long range and nonadditivies of correlations in the liquid state.
Pengaruh Subtitusi Lemak Susu Dengan Berbagai Minyak Nabati Terhadap Total Bahan Padat , Tekstur Dan Waktu Pelelehan

Susu merupakan bahan makanan yang diperlukan untuk pertumbuhan dan perkembangan tubuh. Salah satuprodukolahansusu yang digemariolehmasyarakatadalah es krim. Penelitian ini bertujuan mengetahui pengaruh substitusi lemak susu dengan berbagai minyak nabati terhadap kandungan total bahan padat, tekstur, dan waktu pelelehanes krimHasil yang diperoleh pada penelitian ini adalah substitusi lemak susu dengan minyak nabati (2%) berpengaruh nyata (P 0,05) pada total bahan padat es krim. Manfaatdaripenelitian ini dapatmenambah informasi tentang pengaruh substitusi lemak susu dengan berbagai minyak nabati terhadap kandungan total bahan padat, tekstur dan waktu pelelehan es krim. Kata Kunci : Total Bahan Padat, Tekstur, Waktu Pelelehan, es krim, Minyak Nabati Abstract Milk is a necessary food for growth and development of the body. One of the most popular dairy products is ice cream. This study aims to determine the effect of substitution of milk fat with various vegetable oils on the total content of solid materials, texture, and time of melting ice cream. The results obtained in this study are substitution of milk fat with vegetable oil (2%) significantly (P 0.05) on total solid ice cream. The benefits of this study can add information about the effect of substitution of milk fat with various vegetable oils to the total content of solids, textures and time of melting ice cream.
Analisa The Day of The Week Effect Terhadap Return Mata Uang Virtual Pada Pasar Kriptokurensi

Tujuan penelitian ini adalah untuk mengetahui dan menganalisis pengaruh hari perdagangan terhadap return mata uang virtual pada pasar kriptokurensi. Penelitian ini merupakan studi empiris pada hari perdagangan dan return mata uang virtual. Sampel yang digunakan dalam penelitian ini adalah data return harian kriptokurensi yang terdaftar pada periode 1 Januari 2018 sampai dengan 31 Desember 2018 yaitu berjumlah 26 kriptokurensi. Metode analisis yang digunakan adalah metode analisis deskriptif dan metode analisis regresi linier berganda dengan variabel dummy. Jenis penelitian ini adalah penelitian asosiatif dan data yang digunakan adalah data sekunder yang sudah diolah dan dipublikasikan. Data diolah secara statistik dengan program EViews, yaitu model uji t, uji f Hasil penelitian ini menunjukkan bahwa secara serempak hari perdagangan berpengaruh signifikan terhadap return kriptokurensi. Secara parsial, variabel hari Selasa, Kamis, dan Jumat berpengaruh positif dan signifikan terhadap return mata uang virtual. The purpose of this study was to determine and analyze the influence of the day of the week effect on virtual currency return at the cryptocurrency market. This research was an empirical study on trading day and virtual currency returns. This research was taking 26 cryptocurrencies that listed during January, 1st 2018 until December, 31st 2018 and used daily return of each virtual currencies. The analytical method used is descriptive analysis method and multiple linear regression analysis methods with dummy variables. This type of research is associative research and the data used are secondary data that has been processed and published. Data is processed statistically with the EViews program, namely the t-test model and f test. The results of this study indicate that simultaneously the trading days have a significant effect on virtual currency return. Partially, trading day variables of Tuesday, Thursday, and Friday have a positive and significant effect on virtual currency return.