Miracle-dz/UniFAR-FTUs huggingface dataset:
A metastable Cr carbide of NaCl structure formed by carbon-ion implantation into chromium films

A metastable NaCl-structure Cr carbide was formed by 50 keV carbon-ion implantation into pure chromium metal films. The structure of the carbide phase was identified by selected-area electron diffraction to be face-centred cubic (FCC) with a lattice constant of 0.403 nm. The carbide phase was stable only up to temperature of about 250 degrees C and was destabilized at higher temperature, probably because of oxidation. The formation of Cr carbide was also confirmed by Auger spectroscopy measurements. The heat of formation of the phase was calculated to be less negative than those for Ti and V carbides, i.e. -7 kcal mol-1, which reflected to some extent the metastability of the carbide formed.
Experimental Measurement and Numerical Study of Particle Deposition in Highly Idealized Mouth-Throat Models

Particle deposition in the human mouth-throat is an important factor in evaluating efficiency of drug delivered by inhalation devices, such as pMDIs or DPIs. Current USP standard impactor induction ports (which serve as an in vitro representative of the adult mouth-throat) underpredict in vivo mouth-throat deposition. However, preliminary experimental data in the prototype geometry of a highly idealized mouth-throat has indicated that it is a promising replacement for the USP mouth-throat (Zhang et al. 2004). In this study, partial optimization design of the highly idealized mouth-throat was performed using computational fluid dynamics (CFD) simulations. The performance of six candidate highly idealized mouth-throat geometries, each with a straight tube inlet of inner diameter 17.3 mm, was evaluated experimentally by measuring monodisperse particle deposition efficiency. Gravimetry was used to determine particle deposition in these geometries. Monodisperse particles of di-2-ethylhexyl-sebecate (DEHS) oil with mass median diameters of 2.1–7.5 μm (GSD < 1.1) were used at two steady inhalation flow rates of 30 and 90 l/min. The results showed that, at the higher flow rate of 90 l/min, a mouth-throat with a bend region 8.5 mm in diameter and a curvature radius of 50 mm follows the in vivo average summarized by Stahlhofen et al. (1989) most closely. In contrast, at the lower flow rate of 30 l/min, the mouth-throat with a bend region 7.5 mm in diameter mimics the above in vivo curve but the in vivo-in vitro match is worse than for 90 l/min case. Enhanced particle deposition caused by a Reynolds number effect was observed in all geometries studied. Overall, an adequately designed highly idealized mouth-throat can largely reproduce in vivo mouth-throat deposition. For different flow rates, different key dimensions are required with the present highly idealized mouth-throats in order to adequately reproduce the in vivo average curve.
Tailored Anatase/Brookite Nanocrystalline TiO2. The Optimal Particle Features for Liquid- and Gas-Phase Photocatalytic Reactions

Anatase−brookite composite nanocrystals were synthesized successfully by a controlled sol−gel reaction followed by a prolonged hydrothermal aging or by mild calcinations (300 and 450 °C). The physicochemical and photocatalytic properties of the synthesized TiO2 composites were studied along with several commercially available nanocrystalline TiO2 samples showing different features. Rietveld refinements of the powder X-ray diffraction pattern were used to track the brookite content systematically and to generally assess the phase composition of the different samples and their crystallite sizes. SEM, TEM, and HRTEM were used to characterize the particle morphology, size, and surface faceting. BET/BJH analyses combined with mercury porosimetry determinations were employed to characterize the surface area, porosity, and pore size distribution. The surface state of the TiO2 samples was analyzed by XPS by studying, in detail, the region of oxygen 1s to produce the OH/Otot surface ratio. The photocatalytic activ.
Formation process, reactivity and physicochemical properties of SiO nanoparticles: spectroscopic and computational study

Synthesis and spectral (infrared, Raman and inelastic neutron scattering) examination of SiO thin film, powder and products of their oxidation are reported. Processes of SiO formation and interaction with small species, occurring in gas phase, have been simulated in molecular approach by PM3 quantum chemical (QC) method. The QC-simulated model of the SiO nanoparticle was used as a basic model to QC simulate the interaction of SiO molecules and nanoparticle with O2, CO and H2O in the cluster approach. Structures of nanoparticles, resulting from such interaction, and their vibrational spectra have been QC simulated. Inverted vibrational problems have been solved in each case in order to verify the QC-evaluated models. Mechanism of the SiO high-temperature oxidation in gas phase is proposed and discussed. QC-evaluated models and complete range of corresponding theoretical and experimental vibration spectra represent molecular interactions with the nanoparticles of SiO and related changes in spectral characteristics.
Even-order high-harmonic generation from solids in velocity gauge

We present a velocity-gauge model for the generation of even-order high harmonics, and reveal that the even-order harmonics originate from the multiple-step transitions among the energy bands in momentum space, while the odd-order harmonics are mainly from direct transitions. The lower valence band is found vital for the generation of even harmonics. Relative intensity of even-order harmonics versus the odd orders is calculated and shows a growing trend as the laser field amplitude increases.
Decomposição e liberação de nutrientes acumulados em leguminosas herbáceas perenes consorciadas com bananeira

Evaluating the decomposition of cover crop residues added to the soil allows improving the comprehension of appropriate nutrient supply for commercial crops. This study was carried out under field conditions aiming to evaluate the decomposition and nutrient release from the shoots of perennial herbaceous legumes. The treatments were green cover crops intercropped with banana: groundnut (Arachis pintoi Krapov. & W.C. Gregory.), tropical kudzu (Pueraria phaseoloides (Roxb.) Benth. ), siratro (Macroptilium atropurpureum (Sesse & Moc. ex DC.) Urb. ) and spontaneous vegetation (mainly Panicum maximum Jacq.). These species were cut during the dry (April 1997) and rainy seasons (January 1998). Aboveground cover crop samples were placed in litterbags, which were distributed on the plots soil surface. Dry matter decomposition and nutrient release were monitored through collection of litterbags at 5, 10, 15, 30, 60, 90, 120 and 150 days after cutting the cover crops. Dry matter decomposition of groundnut was the fastest and the spontaneous vegetation was the slowest. The decomposition constants decreased and residue half-lives increased during the dry season. There was a faster release of N, Ca and Mg in the legumes, while spontaneous vegetation presented similar results for P. Among the chemical variables under study, the cellulose and hemicellulose contents were correlated with dry matter loss. N release was correlated with C and hemicellulose contents. Results indicate the potential of perennial herbaceous legumes for nutrient release, particularly in the case of tropical kudzu and siratro.
Efficient Synthesis of Heteroatom (N or S)‐Doped Graphene Based on Ultrathin Graphene Oxide‐Porous Silica Sheets for Oxygen Reduction Reactions

Heteroatom (N or S)‐doped graphene with high surface area is successfully synthesized via thermal reaction between graphene oxide and guest gases (NH3 or H2S) on the basis of ultrathin graphene oxide‐porous silica sheets at high temperatures. It is found that both N and S‐doping can occur at annealing temperatures from 500 to 1000 °C to form the different binding configurations at the edges or on the planes of the graphene, such as pyridinic‐N, pyrrolic‐N, and graphitic‐N for N‐doped graphene, thiophene‐like S, and oxidized S for S‐doped graphene. Moreover, the resulting N and S‐doped graphene sheets exhibit good electrocatalytic activity, long durability, and high selectivity when they are employed as metal‐free catalysts for oxygen reduction reactions. This approach may provide an efficient platform for the synthesis of a series of heteroatom‐doped graphenes for different applications.
Mechanisms of diamond oxidation and their bearing on the fluid composition in kimberlite magmas

Abstract Diamond oxidation experiments were undertaken in a piston-cylinder apparatus at 1150 to 1500 °C and 1 GPa to understand the mechanism of diamond oxidation in kimberlite melts and to determine the main rate-controlling parameters for this process. Only surface graphitization, and no diamond resorption, occurs in melts that are fluid undersaturated (synthetic kimberlite, carbonate melt, alkaline basalt, CaO-MgO-SiO2-H2O-CO2 melts). In contrast, fluid oversaturated conditions (as evidenced by the presence of bubbles) produce resorption features commonly seen in natural diamonds recovered from kimberlites. The diamond oxidation rate is the same in the melts with a free fluid phase, in a pure H2O or CO2 fluid, suggesting that the process of diamond oxidation is its reaction with the fluid and not with the melt. Both CO2 and H2O oxidize diamonds at a similar rate, but produce very different surface features. Therefore, the surface features of natural kimberlite-hosted diamonds may provide information on the relative proportion of H2O and CO2 in the kimberlitic fluid. The common diamond morphologies imply significant amount of H2O. The absence of diamonds with surface graphitization and the abundance of resorbed diamonds in kimberlites suggest the presence of a free fluid phase in kimberlite magmas for hours or days. We found no correlation between the rate and character of diamond oxidation and the physical properties of diamonds (nitrogen content, color).
Short Communications : Reduction of Bacillus cereus Contamination in Biofilms on Stainless Steel Surfaces by Application of Sanitizers and Commercial Detergent

We established the effectiveness of a washing, detergent and sanitizer treatments for reducing Bacillus cereus (B. cereus) contamination in biofilms on stainless steel surfaces. A water treatment did not affect biofilms and chlorine treatments at 200 ppm for 10 min and 300 ppm for 5 min, iodophor at 200 ppm for 10 min, and QAC at 400 ppm for 10 min were used to eliminate all B. cereus cells. B. cereus cells after detergent treatment were eliminated by chlorine at 100 ppm for 10 min, 200 ppm for 5 min, and 300 ppm for 3 min, and with iodophor at 100 ppm for 10 min and 200 ppm for 10 min, and QAC at 400 ppm for 10 min.
Hydration of ions under confinement

Molecular dynamics simulations are used to examine the changes in water density and hydration characteristics of NaCl solutions confined in slit-shaped graphitic pores. Using a structural signature, we define the hydration limit as the salt concentration at which a sharp drop in the hydration number is observed. At small pores (H = 8.0–10 Å), confined water does not possess bulk-like features and remains in a layered arrangement between two surfaces. Despite this high degree of confinement, ions are able to form a quasi-2D hydration shell between two surfaces. Our results indicate the strong propensity of ions to form the first hydration shell, even under extremely confined aqueous environments. The hydration of ions is seen to weakly perturb the oxygen density distributions between two surfaces. The hydration number of Na+ reduces to about 4.15 at a pore width of H = 0.8 nm, when compared with the bulk hydration number of 6.25. At larger pore widths, above H = 16 Å, where bulk-like water densities are observed in the central regions of the pore, the hydration number is above 6.
Extraction of Selected Mono‐ to Tetravalent Metal Ions by 2,6‐Di‐(5,6‐Dialkyl‐1,2,4‐triazin‐3‐yl)Pyridines

Abstract The extraction of selected metals by 2,6‐di(5,6‐diethyl‐1,2,4‐triazin‐3‐yl)‐pyridine (DETP) and 2,6‐di(5,6‐dipropyl‐1,2,4‐triazin‐3‐yl)pyridine (DPTP) was studied. DPTP in 1‐butanol extracts Fe(II) chloride with high selectivity over Cu(II) chloride, while Cu(I) chloride is well extracted. DPTP in 4‐methyl‐2‐pentanone extracts In(III) and Ga(III) thiocyanates with a modest In(III)/Ga(III) separation factor, while In(III) nitrate is extracted very selectively over Ga(III) nitrate. DPTP in the same diluent extracts Nd(III) and Lu(III) thiocyanates with a moderate to good selectivity over Y(III). In extracting nitrates, DPTP in cyclohexanone and DETP in 1,1,2‐trichloroethane/4‐methyl‐2‐pentanone (3/2) discriminate unsatisfactorily between Nd(III) and Y(III). A good selectivity for Nd(III) over Y(III) is attained with DPTP in 1,1,2‐trichloroethane.
Carboniferous Ostracodes in the Rhadamès Basin of Western Libya: Paleoecological Implications and Comparison with North America, Europe and the Ussr

Carboniferous ostracode assemblages from two boreholes in the Rhadames Basin of western Libya are compared with ostracode assemblages of the same age in North America, Western Europe and the USSR. The assemblages of the M'rar and Assedjefar Formations are characteristic of intertidal environments. These are compared with intertidal ostracode faunas from the late Devonian to early Dinantian of Belgium, and with near-shore faunas from the Upper Carboniferous of Spain and northwestern Europe. The assemblage of the Dembaba Formation is characteristic of a substital environment. Similar ostracode faunas have been described from subtidal or offshore deposits in the Devonian and Carboniferous of North America, Western Europe and the USSR. One genus (Rhadamesella) and nine species (Mammoides bouckaerti, Monoceratina kockeli, Marginohealdia africana, Marginohealdia paprothae, Paracavellina fernetae, Cribroconcha streeli, Graphiadactyllis beckeri; Rhadamesella rhadamesensis and Rhadamesella bourdoni) are new.
Physical properties of polymers based on itaconic acid

Mono and diesters of itaconic acid have been pi'epared using linear , branched or cyclic alkane structures . These have been homo and copolymerized to produce a wide range of polymers with differing properties. These range from polyacids to polydiesters to ionomeric structures. Their physical behaviour has been examined and is reviewed herein.
SEED YIELD OF TWO ALFALFA GENOTYPES UNDER DIFFERENT ENVIRONMENTS

A field experiment was conducted at the Agricultural Experiments and Researches Station, Cairo University, Giza, Egypt from 2008 to 2011 to study the influence of cutting treatment before seed production and plant densities on seed yield of two alfalfa genotypes (Laboon and El-wadi El-Gadid). In General, El-wadi El-Gadid surpassed Laboon in seed yield/feddan. Cutting genotypes twice before seed production recorded the highest seed yield and its components. Seed yield was significantly increased with increasing plant density from 8.400 to 134.400 plant/fed. The interaction between harvesting treatment and genotypes was significant for seed yield in 2010 and 2011 years. El-wadi El-Gadid produced the highest seed yield when cut twice. It also recorded the heaviest seed yield under plant density of 134.400 plant/fed. The second order interaction (El-wadi El-Gadid × cutting twice ×134.400 plant/fed) gave the highest seed yield in both years. Highly significant and negative correlation was observed between seed yield and number of pods /plant (-0.32) and seed index (-0.34).
Conformational and Structural Relaxations of Poly(ethylene oxide) and Poly(propylene oxide) Melts : Molecular Dynamics Study of Spatial Heterogeneity, Cooperativity, and Correlated Forward-Backward Motion

Performing molecular dynamics simulations for all-atom models, we characterize the conformational and structural relaxations of poly(ethylene oxide) and poly(propylene oxide) melts. The temperature dependence of these relaxation processes deviates from an Arrhenius law for both polymers. We demonstrate that mode-coupling theory captures some aspects of the glassy slowdown, but it does not enable a complete explanation of the dynamical behavior. When the temperature is decreased, spatially heterogeneous and cooperative translational dynamics are found to become more important for the structural relaxation. Moreover, the transitions between the conformational states cease to obey Poisson statistics. In particular, we show that, at sufficiently low temperatures, correlated forward–backward motion is an important aspect of the conformational relaxation, leading to strongly nonexponential distributions for the waiting times of the dihedrals in the various conformational states.
Determination of Spatial Variability of Nutrient Composition of Soil Solutions in Greenhouses by Using Suction Cups

The spatial variability of pH, EC and concentrations of K+, Ca2+, Mg2+, Na+, and Cl− in the soil solution of a fertigated soil in a greenhouse was studied using suction cups. The considered factors that modify the composition of the soil solution were: soil depth (0.10 and 0.25 m), distribution of nutrients before and after irrigation, evolution during the growth cycle, and location inside the greenhouse. Each parameter was studied separately to determine its effect on the nutrient composition of the soil solution, and consequently to standardize the soil solution sampling and design of fertilizer applications. Significantly higher levels of EC and concentrations of Mg2+, Na+, and Cl− were found at 0.25 m, whereas higher concentrations of and K+ were obtained with suction cups in the topsoil horizon (0.10 m). Irrigation with nutrient solution modified the concentrations of and significantly, and during the growth period the concentrations of pH, and Na+ varied significantly. A simple linear model to estimate the actual soil solution composition from the soil moisture and previous soil solution composition was obtained, showing a close relationship with the experimental values found by means of suction cups after irrigation. This model can be of use in the calculation of the composition of optimized nutrient solutions by means of suction cups. This procedure can also be relevant in the design of optimized nutrient solutions for fertigation, maximizing plant production and minimizing excessive use of fertilizer and pollution in intensive horticultural ecosystems.
Recent advances in cowpea breeding

Cowpea is an important grain legume throughout the tropics and subtropics, covering Asia, Africa, and Central and South America, as well as parts of southern Europe and the United States of America. The use patterns, seed preferences, and cropping systems vary from region to region. Insect pests, diseases, nematodes, parasitic weeds, and drought are major production constraints. Early maturity is preferred everywhere so that cowpeas can be grown in the niches of cereal-based cropping systems, but medium-and late-maturing varieties, with and without photosensitivity, are also required in some regions, to suit the prevalent cropping systems and meet grain and fodder needs. Considerable progress has been made during the past decade in cowpea breeding, and a range of varieties has been developed, combining diverse plant type and maturity with resistance to several diseases, insect pests, and parasitic weeds. Improved varieties have also been developed for grain and fodder and for intercropping with maize, cassava, yam, millet, and sorghum for the benefit of smallholder farmers who practice intercropping and use little or no inputs.
Free-volume distributions of polystyrene probed by positron annihilation : comparison with free-volume theories

The free-volume hole distribution in polystyrene (T g = 95°C, molar weight 106000) has been investigated as a function of temperature. The hole volume distributions are determined from orthopositronium distributions. The hole volumes are distributed between 35 and 200 A 3 . The fractions of free volumes are distributed from 2.0% to 11% of total volume. The obtained free-volume distributions are compared and discussed with the experimental distributions obtained by photochromic and florescent probes and with the Turnbull-Cohen free-volume theory. The distributions of free-volume fractions fit well with the theoretical function according to the Simha-Somcynsky lattice model
Efeito da frequência e amplitude de vibração sobre a derriça de frutos de café

Quality parameters influence directly the coffee price. However, selective coffee harvesting is frequently associated to good quality of this product. This procedure can be performed by mechanical vibration. Therefore, the study of the frequency and amplitude parameters is important for the design of a specific harvesting machine. The objective of this work was to evaluate the effect of the frequency and amplitude of vibration, the coffee variety and the ripeness condition of the fruits upon the harvesting efficiency. The vibration tests were done in laboratory using an electromagnetic shaker. The tests were done using amplitudes in the range of 3.75 to 7.50 mm and frequencies in the range of 13.33 to 16.67 Hz. Branches of coffee plants of Mundo Novo variety were tested. The highest harvesting efficiency was obtained when using the 26.67 Hz frequency of vibration. The highest harvesting efficiency was obtained when an amplitude of 7.5 mm was used. It was also observed that the number of fruits per stem influences the harvesting efficiency of the coffee fruits of the Mundo Novo variety.
Adsorption and Desorption of Reactive Dyes onto Chitin and Chitosan Flakes and Beads

A study was undertaken to analyze the adsorption and desorption of four Reactive dyes, i.e. Reactive Yellow 84 (RY 84), Reactive Red 11 (RR 11), Reactive Black 5 (RB 5) and Reactive Black 8 (RB 8), onto chitin (sorbent 1) and chitosan in the form of flakes (sorbent 2) and beads (sorbent 3). The maximum adsorption capacity of sorbents 1, 2 and 3 and the quantity of desorbed dye were determined for the four dyes and the three types of sorbent examined. For all the Reactive dyes, the adsorption capacities of sorbents 2 and 3 were higher than that of sorbent 1, with the desorption efficiency being lower than the efficiency of the adsorption process. The highest efficiency of dye release, ca. 90%, was obtained for sorbent 1 and the chlorotriazine dyes.
Heterosis in numbers of differentiated, degenerated, and surviving spikelets and their relations to the dry matter production in F1 hybrids of rice

Abstract Heterosis in the number of differentiated, degenerated, and surviving spikelets in two important Chinese F1 hybrids Shanyou 63 (SY63) and Yayou 2 (YY2) and their parents was observed under solution culture conditions. The results indicated that the number of differentiated, degenerated, and surviving spikelets all showed a very high value for mid-parental (MP) heterosis in the hybrids at both panicle and plant levels. The increase in the number of surviving spikelets primarily depended on that of the number of differentiated spikelets. The percentage of degenerated spikelets showed a positive value for MP and higher-parental (HP) heterosis (increase) in SY63, while it showed a negative value for MP and HP heterosis (decrease) in YY2. Morphologically, the components of the number of surviving spikelets increased in the hybrids, especially the number of surviving secondary rachis branches. Dry matter production at heading showed a high value for MP and HP heterosis. However, the ratio of dry matter weight to the number of differentiated spikelets did not show a MP heterosis. The hybrids showed a lower percentage of degenerated spikelets for the same ratio of dry matter weight to the number of differentiated spikelets. The N uptake in the hybrids showed a MP and HP heterosis, but the efficiency of the N in producing the number of surviving spikelets showed a negative value for MP and HP heterosis. The MP and HP heterosis in the sink-source ratio of the number of surviving spikelets to the leaf area varied considerably with the combinations. These findings suggested that still many characters could be further improved in F1 hybrid rice.