Miracle-dz/UniFAR-FTUs huggingface dataset:
Adubação fosfatada no meloeiro-amarelo: reflexos na produção e qualidade dos frutos

The culture of melon (Cucumis melo L.) has a great economic and social expression for the Northeast region of Brazil. Although its importance in the Brazilian agriculture, and the low levels of phosphorus (P) on tropical soils, there are reduced number of researches regarding P fertilization for this culture, even though is frequently mentioned that this nutrient would have preponderant rules on the development, growth and quality of the fruits. Thus, the objective of this study was to evaluate the effect of P doses on the production and quality of yellow cantaloupes, hybrid Goldex F1, growing under Teresina-PI conditions. The experiment was composed by 5 P doses (0, 120, 240, 360 and 480 kg ha-1 of P2O5), carried out in four randomized blocks design. The fruits were harvested at 75 days after planting, and evaluated the total production; production of commercial fruits; mass and number of fruits per plant; length and diameter of fruits; pulp thickness, soluble solids, acidity and maturation index. The results indicated that the total and commercial production, mass and number of fruits as well as acidity increased with P doses, reaching the maximum values at 278 kg ha-1 P2O5. Doses above 278 kg ha-1 P2O5 harmed the productivity. The fruits length and the diameter, and the pulp thickness increased until reaching a maximum in 355 dose kg ha-1 of P2O5, although with little improvement from 278 to 355 kg ha-1 of P2O5. The level of total soluble solids was not affected by P fertilization. Under similar conditions to this research, it is recommended a dose around 275 kg ha-1 de P2O5.
I-V characteristics and liquid motion in needle-to-plane and razor blade-to-plane configurations in transformer oil and liquid nitrogen

Current-voltage (I-V) characteristics are measured in a negative needle-to-plane configuration and a negative razor blade-to-plane configuration in transformer oil and liquid nitrogen. Linear pots of V vs. I/sup 1/2/ in the former configuration of V vs. I/sup 1/3/ in the latter configuration are obtained respectively in the space-charge limitation (SCL). The liquid motions in the above two configurations in SCL are computed respectively from both the Navier-Stokes equation and the continuity equation by the finite-difference method. From the experimental and computational results of the liquid motions, the relations between V and I in two configurations are derived, respectively. >
Effect of oxygen impurities on atmospheric-pressure surface streamer discharge in argon for large gap arc breakdown

We report the results of a computational study that investigates the effect of impurities (molecular oxygen) on the development of argon surface streamers at atmospheric-pressure conditions. A continuous surface streamer has been proposed as a low-voltage mechanism to generate a conductive bridge for arc breakdown of a large interelectrode gap at high pressures. The streamer discharge model is based on the self-consistent, multispecies, continuum description of the plasma. Below a threshold voltage, no streamer discharge is observed and charge is localized only in the vicinity of the anode in the form of a localized corona. Above this voltage threshold in pure argon, a continuous conductive streamer successfully bridges the gap between two electrodes indicating high probability of transition to the arc. For small oxygen impurities (less than 5%), the threshold voltage is found to decrease by a few hundred volts compared to the threshold voltage in pure argon while the streamer induction time increases. No.
A Subject-Independent Machine Learning Model to Recognize Hand Gestures from Surface Electromyography Signals

Surface Electromyography (sEMG) based gesture recognition has enabled many prosthetic and rehabilitation applications. This paper presents a study on the generalization ability of machine learning models for sEMG-based automatic hand gesture recognition to improve the user experience and efficiency of prosthetic and rehabilitation applications. Accordingly, user-independent and multi-day classification algorithms are developed in an effort to reduce calibration times while maintaining considerable accuracies for gesture recognition. The development of the whole processing pipeline is considered, including signal acquisition, preprocessing and filtering, windowing and feature extraction, dimensionality reduction, and classification. Considering implementation on the resource-constraint embedded platform, a lightweight model was aimed in this study rather than a large complex model. Hence, an LDA-based classification algorithm was developed on the publicly available putEMG dataset achieving an average accuracy of 77.89% on subject-independent hand gesture classification, establishing a benchmark for further research.
Synthesis of New Functionalized Chiral Ionic Liquid and Its Organocatalytic Asymmetric Michael Addition

Abstract A novel recyclable functionalized chiral ionic liquid has been developed to promote asymmetric Michael additions of cyclohexanone to both aryl and alkyl nitroolefins in the presence of 20 mol% of organocatalyst 4 in MeOH. The process affords synthetically valuable chiral products in good yields (up to 93%) and high enantioselectivities (up to 92%). The chiral ionic liquid could be easily reused six times without remarkable decrease in yields and enantioselectivities. GRAPHICAL ABSTRACT
Activation of methane on iron, nickel, and platinum surfaces: a molecular orbital study

Surface metal atom insertion into methane CH bonds (oxidative addition) has been studied for Fe(100), rough Fe(100), Fe(110), Ni(100), Ni(111), and Pt(111) surfaces by using ASED molecular orbital theory and cluster models. All transition states have in common CH stretches of 0.4-0.5 A and three-centered metal-carbon, metal-hydrogen, and carbon-hydrogen bonding derived from two methane sigma orbitals, the empty sigma*, and metal s + d band orbitals. For iron the predicted order of activity is rough Fe(100) > Fe(100) > Fe(110) and for nickel the order is Ni(100) > Ni(111). The higher barriers for the more closely packed surfaces are found to be related to the stronger metal bonds in these surfaces. The calculated activation energies on Ni(100) and Ni(111) are close to recent experimental determinations, and a low value obtained for Pt(111) suggests more experiments are needed.
Optimal Stealthy Attack to Remote Estimator for Estimation Error Regulation

This paper proposes an attack strategy for remote estimators in cyber-physical systems. In contrast with the common approaches by maximizing the state estimation difference and estimation error covariance of a remote estimator, we consider the scenario where attackers expect to regulate the estimation error to the value arbitrarily defined by attackers, which not only enables attackers to release attacks of different intensities according to their intentions, but also reduces the possibility detected by the amplitude detector and the human monitor. By taking advantage of the dynamic programming, an explicit expression of the optimal attack sequence is derived, and its convergence and feasibility are analyzed. Finally, simulation results are presented to validate the effectiveness of the proposed strategy.
The chemistry of methanol on the TiO2(110) surface: the influence of vacancies and coadsorbed species

The chemistry of methanol was explored on the vacuum annealed TiO2(110) surface, with and without the presence of coadsorbed water and oxygen, using temperature programmed desorption (TPD), high resolution electron energy loss spectroscopy (HREELS), static secondary ion mass spectrometry (SSIMS) and low energy electron diffraction (LEED). The vacuum annealed TiO2(110) surface possessed about 8% oxygen vacancy sites, as determined with H2O TPD. Although evidence is presented for CH3OH dissociation to methoxy groups on the vacuum annealed TiO2(110) surface using SSIMS and HREELS, particularly at vacancy sites, the majority of the adlayer was molecularly adsorbed, evolving in TPD at 295 K. Although no evidence of irreversible decomposition was found in the TPD, dissociative CH3OH adsorption at 135 K on the vacuum annealed TiO2(110) surface led to recombinative desorption states at 350 and 480 K corresponding to methoxys adsorbed at non-vacancy and vacancy sites, respectively. Coadsorbed water had little or no influence on the chemistry of CH3OH on the vacuum annealed TiO2(110) surface, however new channels of chemistry were observed when CH3OH was adsorbed on the surface after O2 adsorption at various temperatures. In particular, O2 exposure at 300 K resulted in O adatoms (via dissociation at vacancies) that led to increased levels of CH3O–H bond cleavage. The higher surface coverage of methoxy then resulted in a disproportionation reaction to form CH3OH and H2CO above 600 K. In contrast, low temperature exposure of the vacuum annealed TiO2(110) surface to O2 resulted in low temperature state of O2 (presumably an O2- species) that oxidized CH3OH to H2CO by C–H bond cleavage. These results provide incentive to consider alternative thermal and photochemical oxidation mechanisms that involve the interaction of organics and oxygen at surface defect sites.
Geometric and Mechanical Properties of Mung Bean (Vigna Radiata L.) Grain: Effect of Moisture

In this research, selected geometric and mechanical properties of mung bean grain were evaluated as a function of moisture content. Five levels of moisture content ranging from 7.28 to 17.77% d.b. (dry basis) were used. The average length, width, thickness, arithmetic and geometric mean diameters, sphericity, thousand grain mass and angle of repose ranged from 5.145 to 6.199 mm, 3.760 to 4.474 mm, 3.537 to 4.223 mm, 4.147 to 4.965 mm, 4.090 to 4.893 mm, 0.795 to 0.789, 52.3 to 64.6 g, and 25.87 to 29.38° as the moisture content increased from 7.28 to 17.77% d.b. , respectively. The bulk density was found to be decreased from 821.3 to 745.2 kg/m3, whereas the grain volume, true density, porosity, terminal velocity, and projected area were found to be increased from 27.88 to 47.33 mm3, 1230.0 to 1456.7 kg/m3, 30.43 to 46.57%, 4.86 to 5.29 m/s, and 17.48 to 19.26 mm2, respectively. There is a 43% increase in surface area from grain moisture content of 7.28 to 17.77% d.b. The static coefficient of friction on various surfaces increased linearly with the increase in moisture content. The rubber as a surface for sliding offered the maximum friction followed by galvanised iron, medium density fibreboard, stainless steel, aluminium and glass sheet. As moisture content increased from 7.28 to 17.77%, the rupture forces values ranged from 67.39 to 39.44 N; 63.86 to 42.18 N, and 53.96 to 41.79 N for thickness (Z axis), length (Y-axis) and width (X-axis), respectively.
Role of coulombic centers on insulator surface breakdown characteristics

Pulse surface breakdown (flashover) and conditioning characteristics of polycrystalline alumina and single crystal quartz in vacuum were investigated. An electrode system which greatly facilitates time-coordinated electrical and optical measurements of surface discharges along insulators was designed and validated. The surface flashover characteristics obtained using the electrode system are discussed and compared with those obtained using the conventional parallel plane electrode system. A procedure for the conditioning of insulators in vacuum is presented. The single crystal quartz specimens were found to exhibit higher conditioned breakdown strength ( approximately 350 kV/cm) compared to polycrystalline alumina ( approximately 230 kV/cm). The mechanisms associated with the breakdown characteristics are discussed in terms of negative and positive space charge formation involving coulombic centers (traps) and adsorbed layers. The pre-breakdown and breakdown X-ray activities and luminosity are also presented and discussed. >
Increasing root and leaf growth and yield in Mg‐deficient faba beans (
 Vicia faba
 ) by MgSO
 4
 foliar fertilization

Magnesium (Mg) deficiency reduces yield and quality of crops as Mg is involved in carbohydrate and protein anabolism. Foliar application of MgSO4 represents a means of ameliorating the nutritional status of crops growing under conditions of deficiency. Foliar Mg application has been demonstrated to increase the chlorophyll concentration and vegetative yield of plants. However, in crop plants used for seed production, the limited number of available studies provides only conflicting results in terms of the efficiency of Mg leaf application on yield and quality. We have examined the effect of increasing Mg foliar application rates on differentially developed leaves and leaf stages with regards to Mg concentration, chlorophyll concentration and biomass formation. Our data reveal that in order to obtain significant effects MgSO4 concentrations in the spraying solution should be higher than 50 mM, as lower concentrations did not lead to significant changes in the vegetative or generative material. Positive effects of the foliar application on chlorophyll concentration and leaf area were only measured in leaves treated with 200 mM foliar MgSO4. The application of Mg did not affect the parameters chlorophyll, ion concentration and leaf area in the newly developing leaves, but it had an important influence with regard to yield traits, especially on the formation of pods. The quality of the seeds with regard to the protein concentration was reduced in response to the magnesium deficiency treatment, but the application of foliar magnesium prevented a significant loss of protein.
Thermodynamics of struvite formation

Struvite is a phosphate mineral that can form hard-scale deposits in the recycle components of livestock waste management systems that utilize recycled lagoon effluent to transport waste. Previous research of struvite formation in piping systems has been hindered by the presence of erroneous solubility constant values in the literature and the use of a set of less-than-comprehensive equilibrium equations. This article identifies the erroneous solubility product constant commonly found in text books and documents an apparently correct value.
Comparison of Catalyzed and Noncatalyzed Oxidation of Azo Dye and Effect on Biodegradability

Catalytic and noncatalytic oxidations of diluted (0.5 g/L) aqueous azo dye (Orange II) solutions were performed at temperatures from 180 to 240 °C and oxygen partial pressure of 10 bar. The catalyst consisted of alumina and copper and zinc oxides. Dye−decay curves indicate that nearly complete removal of Orange II was achieved after 10 min at 240 °C in experiments without the catalyst while only about 3 min was needed in the presence of the catalyst at 180 °C. The TOC removal rates were found lower than those of the dye, thus implying the formation of intermediate products that are more resistant to further oxidation to carbon dioxide. On the basis of concentration−time behavior and the intermediate products identified, it is concluded that both catalytic and noncatalytic oxidations of Orange II obey a parallel consecutive reaction pathway involving free radicals. Aerobic biodegradability of Orange II solutions treated by catalytic and noncatalytic oxidation processes increases with time. The ratio of BOD.
Two Different Surface Properties of Regenerated Cellulose due to Structural Anisotropy

Contact angles of water droplet on regenerated cellulose films as an index of wettability were positively correlated with the orientation of (1-10) crystal planes and crystallinity. Because hydroxyl groups of cellulose are located at the equatorial positions of glucopyranose rings, corresponding to the surface of (1-10) crystal planes, the hydrophilicity of the (1-10) surface is expected to be very high. It is natural, therefore, that higher planar orientation of (1-10) planes and crystallinity lead to higher density of hydroxyl groups on the surface of regenerated cellulose films resulting in higher wettability. In contrast, hydrogen atoms are located at the axial positions of the glucopyranose rings, corresponding to the surface of (110) planes. Thus, the (110) surface is expected to be hydrophobic, and the surface energy obtained by computer simulations was far lower than that of the (1-10) surface. This suggests that cellulose with complementary properties, i.e., hydrophobicity, may be created by structural controls such as reversing the planar orientation from (1-10) to (110). Although it was not possible to reverse this orientation completely, post-treatments with a nonpolar solvent (e.g., hexane), liquid ammonia or hot glycerol can somewhat control the wettability of regenerated cellulose films.
Assessment of Heavy Metal Contamination of Wetland Soils from a Typical Aquatic–Terrestrial Ecotone in Haihe River Basin, North China

Surface soils were collected in the aquatic–terrestrial ecotone (ATE) of Yongnianwa wetland, downstream of Haihe River basin of North China in June of 2007. Samples were subjected to a total digestion technique before they were analyzed for total concentrations of Cr, Cu, Ni, Pb, and Zn to investigate their pollution levels in the ATE. The contamination index, integrated contamination index, geoaccumulation index, toxic units, and sum of toxic units were adopted to assess the heavy metal contamination levels and ecotoxicity, respectively. The results showed all the selected element concentrations in upland soils of the ecotone were relatively higher than those in the lowland soils. No Cr pollution was observed in all soil samples, but almost all samples were slightly polluted by Cu, Ni, Pb, and Zn except for Site 1. The contamination indexes and geoaccumulation indexes consistently presented no contamination for Site 1 and slight contamination for other sites. The STUs increased from lowland to upland, but the whole level of toxicity in this ecotone was relatively low.
Properties of sub soils in relation to various measures of surface area and water content

SUMMARY Neither the specific surface area values (from N, sorption) nor the ethylene glycol monoethyl ether (EGME) retention values of 21 soil samples from New Zealand and Fiji could all be accounted for by the sum of the contributions from their component minerals. Much EGME is probably retained by internal surfaces of interlayered and interstratified clay minerals. EGME retention correlated well with cation exchange capacity (CEC) and a number of measures of water content of these soils. The water contents of air-dried soils (measured as ‘moisture factors’ or the ratios of air-dry and oven-dry weights) showed almost as close a relationship to CEC as EGME retention for this set of 21 subsoils. Moisture factors and CEC were closely related, within groups defined by dominant clay mineralogies, for a much wider selection of 1318 New Zealand soil horizons with low carbon contents. The relationships between surface area and a number of other soil properties including dispersibility of soils were also examined.
How anion and cation species influence the tribology of a green lubricant based on ionic liquids

A group of halide-free ionic liquids involving two different anions (methyl sulfate and methyl sulfonate) and four types of cations (short-chain tetraalkylammonium, dialkylpyrrolidinium, choline, and methoxycholine) were investigated as 2.5 wt% additives in glycerol as a model base fluid, yielding highly biodegradable polar lubricants for study of ionic liquid interaction with a substrate. The results were compared to the behavior of conventional bis(trifluoromethylsulfonyl)imide ([Tf2N]) ionic liquids with identical counter-ions. The neat ionic liquids (100 wt%) were tested in identical manner and compared to the behavior when they operate as additives. Tribotests were performed in a ball-on-disc configuration under boundary conditions, by lubricating steel–steel couples at room temperature and at 100°C. Wear reduction was achieved for all temperatures, and the results were strongly anion-dominated, with good results for methyl sulfates and the [Tf2N] references. Particularly for higher temperatures, ionic liquids were also able to reduce friction by a substantial amount, with a clear order between the individual anions, and the lowest values were again obtained for methyl sulfates. Cationic influence on the test results was found to be subordinate for both temperatures. It could be recognized that at elevated temperatures, the newly formulated lubricants containing an ionic liquid as an additive behaved similarly to neat ionic liquids in terms of friction and wear reduction. Using X-ray photoelectron spectroscopy analyses, the formation of a beneficial iron sulfide film was detected, with the sulfur originating from the sulfate of the ionic liquid, presumably as a result of a redox reaction with metallic iron. For this mechanism, a hypothesis for possible reaction pathways was developed.
SO2-Ethanol-Water (SEW) Pulping: II. Kinetics for Spruce, Beech, and Wheat Straw

Abstract SO2-ethanol-water (SEW) delignification kinetics for spruce, beech, and wheat straw are presented. All these species produce pulps using SEW cooking liquor and follow first order delignification kinetics at similar bulk delignification rates. However, residual delignification is much slower for beech than for spruce. The hemicelluloses retention (135°C) and cellulose degradation kinetics are also characterized for beech SEW pulping. Xylan and glucomannan are removed from the pulp following first-order kinetics with a higher rate constant for xylan. Cellulose is retained in the fibers until kappa number 9, after which it starts to dissolve in the liquor. The yield also drops significantly in the region of kappa numbers 9–7. Cellulose degradation is followed by intrinsic viscosity measurements and is found to be zero order in cellulose. The rates are higher at 135 and 145°C for beech SEW pulping than for spruce.
Chemical and Antimicrobial Properties of Essential Oils of Five Moroccan Pinaceae

Abstract The composition of the essential oils isolated from the needles of Pinus halepensis M. , P. canariensis C. , P. pinaster S. , P. pinea L. and P. brutia grown in Morocco were investigated by GC and GC/MS. The oil of P. halepensis was found to be rich in monoterpenes hydrocarbons (78.1%), with α-pinene (23.3%) being the major component. The most abundant compound in P. pinea oil was also α-pinene (37.0%), while the oil of P. brutia contained β-pinene (33.6%) as a major component. Sesquiterpene hydrocarbons were found to dominate the composition of P. canariensis (91.6%) and P. pinaster (64.6%), with the main components being germacrene D (62.5%) and β-caryophyllene (22.2%), respectively. The oils and α-pinene, myrcene and β-caryophyllene were tested for their inhibitory effect against 21 strains of bacteria. Examination of the antibacterial activity revealed that only P. pinaster and P. pinea oils exhibited a definite activity against all organisms tested. Compared to gentamicin, tetracycline and chloramphenicol, both oils showed a marked antiseptic activity.
Dependence of the average transversal on the longitudinal dimensions of statistical coils formed by chain molecules

The transversal dimension of the statistical coil formed by a long-chain molecule in solution or in bulk rubber is independent of the longitudinal dimension, h1, of the coil as long as h1 is small compared with the length of the stretched molecule. On the other hand, the lateral dimension of a coil whose longitudinal vector, h1, is oriented in the direction of stretch undergoes a forced contraction during the deformation of bulk rubber. The forced contraction of the transversal dimension is therefore supplying an extra contribution to the entropy change. Its amount has been estimated in earlier work and it influences the numerical factor occurring in the formula connecting the strain-stretch relation for rubber with the molecular weight of the net fragments.