Miracle-dz/UniFAR-FTUs huggingface dataset:
EVALUATION AND MODELING OF TWO-STAGE OSMO-CONVECTIVE DRYING OF APPLE SLICES

ABSTRACT Two-stage drying kinetics of cylindrical pieces of apples were evaluated by subjecting test samples first to various osmotic treatments and then to convective air drying to complete the drying process. Osmotic drying was carried out with cut apple cylinders of three different sizes (12, 17 and 20 mm diameter), all with a length to diameter ratio of 1 : 1, in a well agitated large tank containing the osmotic solution at the desired temperature. Solution to fruit volume ratio was kept greater than 60. After the osmotic treatment, apple slices were further dried in a cabinet drier at an average temperature 58°C. A central composite rotatable design (CCRD) with five levels of sucrose concentrations (34–63°Brix) and five temperatures (34–66°C) was used for osmotic treatment. Half-drying time and solids gain time were used as measures of rate of drying and associated diffusion coefficients for moisture loss and solids gain were evaluated. Half-drying time decreased with an increase in temperature or concentration, or a decrease in sample size. Diffusion coefficients were lower for smaller samples, and were higher for migration of moisture as compared to solids. For a given level of moisture removal, air drying times were shorter than osmotic drying times. Composite models were developed to describe the effect of process variables and particle size on the drying behavior of apple slices.
Detection of Density Jump in Laser-Induced Shock Wave Plasma Using a Rainbow Refractometer

A special interferometric technique with high sensitivity has been devised on the basis of rainbow refractometry without the use of an additional and delicate amplitude-splitting setup. This new technique was used for the characterization of shock wave plasma induced by a Q-switched Nd:YAG laser on various metal samples under reduced surrounding gas pressures. An unmistakable signal of the density jump was detected simultaneously with the observation of the emission front signal. It proved that the emission front and the front of the blast wave coincided and moved together with time at the initial stage of the secondary plasma expansion. However, at a later stage, the emission front began to separate from and left behind the blast wave front propagating in the surrounding gas at low pressures. With the use of Cu and Zn samples, the experimental results showed that the separation of the emission front and blast wave front took place at about 5 mm above sample surface for laser energy of 140 mJ.
Analyzing Molecular Current-Voltage Characteristics with the Simmons Tunneling Model: Scaling and Linearization

Use of the Simmons model for analyzing tunneling transport across molecular junctions is reviewed, and its inherent limitations are examined, specifically for cases where there are no molecular length-dependent data (to extract a decay parameter), be it for experimental reasons or because of changes of the molecular energetics or packing with molecular length. The potential barrier across a molecular junction is shown to be strongly bias-dependent, much more so than is assumed in the commonly used version of the Simmons model. The means to distinguish true tunneling from conduction via pinholes (or hot spots) are also considered. Power expansion to the Simmons model shows that I/V vs V2 plots should be linear over that range, thus providing a simple and standardized parameter extraction. From such plots, we can extract values for the equilibrium conductance and for the “shape factor”, a complementary parameter that describes the shape of the I−V relations. The applicability of these two parameters for des.
Femtosecond intervalley scattering in GaAs

We report the measurement of intervalley scattering rates for optically excited carriers in GaAs. The measurements were performed using optical pulses of 6 fs duration and an energy distribution centered at 2.0 eV. The average rates for Γ→X and Γ→L intervalley scattering were separately estimated by varying the sample temperature.
Retention of Nitrogen by a Nitrogen‐Loaded Scotch Pine Forest

The capacity of forests to store added N and how this excess N might interact with other nutrients is not well understood. We studied N retention in a Scotch pine (Pinus sylvestris L.) forest that had received two decades of annual additions of N as NH 4 NO 3 at four rates (N0-N3, equivalent to 0, 36, 72 and 108 kg N ha -1 yr 1 ), with and without supplementary additions of P and K. The highest N treatment (N3) was suspended three years before this study. Leaching of inorganic N was measured beneath lysimeters with and without living tree roots inside them, and the fate of 15 N injected into the mor layer was traced by sampling understory vegetation, soil to 20-cm depth, and leachates. Leaching of inorganic N increased with increasing N dose and was dominated by NO 3 on plots to which N had been added. In the suspended N3 treatment, leaching of N was lower than in the N2 treatment. The presence of tree roots greatly reduced leaching of N. The occurrence of labeled NO - 3 under lysimeters to which labeled NH + 4 had been added showed that nitrification was important in treatment N2, but not in N1, suggesting that additions of >30 kg N ha -1 yr -1 are needed to induce larger net nitrification at this site. Our data showed (i) that trees were an important sink for N, (ii) that additions of P and K had a marginal positive effect on N retention, and (iii) that leaching from previously N-loaded forest rapidly decreased when the N load was removed.
New View to Obtain Dryer Food Foams with Different Polysaccharides and Soy Protein by High Ultrasound

The objective of this work was to determine the effects of high intensity ultrasound application on the foaming properties of soy protein-polysaccharides mixed solutions. To this end, foaming parameters during foam formation were analyzed. The samples were sonicated for 20 min using ultrasonic processor Vibra Cell Sonics, and model VCX 750 at a frequency of 20 kHz and an amplitude of 20%. The foams were produced by a Foamscan instrument. The evolution of the bubble size change in the foam was also determined by a second CCD camera. For all foamed systems, at two pHs 3 and 7, Foam expansion and Relative Foam Conductivity showed a great increase after ultrasonic treatment. Other parameters studied did not show difference. On the other hand, Final Time of Foaming and the Total Gas Volume incorporation for foams formation were correlated with the Relative Foam Conductivity decrease and the Foam Expansion increase when HIUS were applied in every system. Comparative bubble size and shape during the foam formation according to the treatments and pH used confirmed the parameters results.
Groundwater Quality under Conventional and No Tillage: II. Atrazine, Deethylatrazine, and Metolachlor

The effect of no tillage (NT) and conventional tillage (CT) on the contamination of shallow groundwater by atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine), deethylatrazine (2-chloro-4-amino-6-isopropylamino-s-triazine), and metolachlor (2-chloro-N-(ethyl-6-methylphenyl )-N-(2-methoxy-1 -methylethyl) acetamide) at nominal depths of 1.2, 1.8, 3.0, and 4.6 m was studied during four successive crop-years in four corn (Zea mays L.) fields with loam soil. Atrazine and deethylatrazine were almost always present in the shallow groundwater. Atrazine concentrations were below the U.S. Environmental Protection Agency (USEPA) lifetime health advisory (LHA) of 3 μg/L in more than 99% of the 920 groundwater samples from the two tillage treatments. Atrazine concentrations, although low, were significantly higher under NT than CT (P < 0.05) at the 1.8 and 3.0 m depths. Deethylatrazine concentrations were also low but were generally higher than those of the parent compound. They were significantly higher under NT than CT at the 1.2 and 1.8 m depths (P < 0.1), as well as at 3.0 m (P < 0.01). Metolachlor was detected in only 25% of the samples and concentrations were well below the USEPA LHA of 100 μg/L. There was no tillage treatment effect on metolachlor concentration. Results from this study suggest a low potential for serious pollution of shallow groundwater from application of atrazine and metolachlor at agronomically recommended rates in tile-drained corn fields in cold humid regions under both CT and NT practices. However, atrazine leaching appears to be greater under NT than under CT.
Characterization of agarose as immobilization matrix model for a microbial biosensor

Microbial biosensors are promising tools for the detection of specific substances in different fields, such as environmental, biomedical, food or agricultural. They allow rapid measurements, no need for complex sample preparation or specialized personnel and easy handling. In order to enhance the managing, miniaturization and stability of the biosensor and to prevent cell leaching, bacteria immobilization is desirable. A systematic characterization procedure to choose a suitable immobilization method and matrix, was proposed in this study. Physical properties, storage stability mass transport phenomena and biocompatibility were evaluated, employing agarose as the model matrix. Preliminary essays with bioluminescent bacteria detecting Tributyltin were also carried out.
Effects of Silica Dioxide Nanoparticles on the Embryonic Development of Zebrafish

To assess the aquatic ecosystem safety of silicon dioxide (SiO2) nanoparticles (NPs), we studied the toxicity of the SiO2 NPs and SiO2 bulk particles (BPs) using zebrafish. Our results show that the SiO2 NPs can significantly affect the development of zebrafish embryos, while there is no obvious effect on survival and development of embryos was found in SiO2 BPs exposure group. The content of malondialdehyde (MDA) in zebrafish larvae exposed to the SiO2 NPs for 108 hours, increased significantly in dose-dependent manner. These results suggest that the SiO2 NPs have toxic effects on the development of zebrafish embryos and the effects could be resulted by oxidative damage.
Structural turbulence in polymer solutions

The appearance of structural turbulence in polyisobutylene solutions at low Reynolds numbers has been detected and analyzed. This type of turbulence is characterized by a critical shear stress rather than a critical Reynolds number. The critical shear stress decreases with increasing molecular weights of dilution. The role of deformability of the polymer chains under shear flow is found to be significant.
NUCLEOBASE-SPECIFIC QUENCHING OF FLUORESCENT DYES. 1. NUCLEOBASE ONE-ELECTRON REDOX POTENTIALS AND THEIR CORRELATION WITH STATIC AND DYNAMIC QUENCHING EFFICIENCIES

Intermolecular static and dynamic fluorescence quenching constants of eight coumarin derivatives by nucleobase derivatives have been determined in aqueous media. One common sequence of the quenching efficiency has been found for the nucleobases. The feasibility of a photoinduced electron transfer reaction for the nucleobase-specific quenching of fluorescent dyes is investigated by the calculation of the standard free energy changes with the Rehm−Weller equation. A complete set of one-electron redox potential data for the nucleobases are determined electrochemically in aprotic solvents for the first time, which are compared with values obtained by various other methods. Depending on the redox properties of the fluorescent dyes, the sequences of the quenching efficiencies can be rationalized by the orders of electrochemical oxidation potentials (vs NHE) of nucleosides (dG (+1.47 V) < dA < dC ≈ dT < U (≥ +2.39 V)) and reduction potentials (dG (< −2.76 V) < dA < dC < dT < U (−2.07 V)). The correlation between.
Cultivo de cana-de-açúcar em argissolo tratado com lodo de esgoto: I - Disponibilidade de nitrogênio no solo e componentes de produção

Sewage sludge (SS) may be used as a nutrient source in agricultural soils, resulting in environmental and economical benefits, provided that specific technical criteria are applied. Unlike field conditions, residue application rates are estimated based on N mineralization trials under optimum temperature and humidity conditions. The objective of this study was to verify whether it is necessary an addition of mineral N (0, 60 and 120 kg ha-1 N) to sewage-sludge (14 and 16 t ha-1, dry weight) applied to sugarcane ratoon. Sugarcane (RB855536) was cultivated under field conditions on an Ultisol. The experiment was evaluated twice (from October 2002 to August 2003 - 2003/2004 growing season and October 2003 to October 2004 - 2004/05 growing season). Eight treatments were tested: (a) control; (b) mineral fertilization (120 kg ha-1 N + 150 kg ha-1 K2O); (c) LE + 0N, incorporated into soil soon after application (ISA); (d) LE + 0N, incorporated into soil 60 days after application (IS60A); (e) LE + 60 kg ha-1 N (ISA); (f) LE + 60 kg ha-1 N (IS60A); (g) LE + 120 kg ha-1 N (ISA); and (h) LE + 120 kg ha-1 N (IS60A). The SS was obtained by an aerobic-biological based process and application rates were calculated considering N mineralization to supply 120 kg ha-1 N. SS application resulted in organic nitrogen increments in the two study periods in the 0-20 cm layer only. An increase in soil inorganic N (N-NO3- + N-NH4+) was observed with N fertilization in the 20-40 cm layer in 2003/04 and in 0-20 and 20-40 cm in 2004/05. SS application resulted in a higher stalk production of around 27 %, compared to the treatments without SS. The sugarcane sucrose content expressed as recoverable total sugar (RTS) was statistically greater due to SS application in the 2004/05 growing season. In this case, no differences were observed between the addition of 60 or 120 kg ha-1 mineral N.
Heterogeneous Chemical Processing of 13NO2 by Monodisperse Carbon Aerosols at Very Low Concentrations

The heterogeneous reaction of NO2 with different carbon aerosol particles was investigated in situ. The NO2 was labeled with the β+-emitter 13N (half-life 10.0 min) which allowed application of NO2 at very low concentrations. The carbon aerosol was either produced by a spark discharge generator using graphite electrodes or by a brush generator resuspending commercial soot material. Monodisperse size cuts between 50- and 490-nm diameter were selected and mixed with the 13NO2. After a defined reaction time, the different reaction products were separated by means of selective traps and detected on-line by γ-spectrometry. A sticking coefficient for chemisorption of NO2 between 0.3 × 10-4 and 4.0 × 10-4 and a rate constant for the reduction of adsorbed NO2 to NO(g) between 4.0 × 10-4 and 9.4 × 10-4 s-1 were determined for both aerosols. The sticking coefficient obtained in this study in situ with aerosol particles is 2 orders of magnitudes smaller than the uptake coefficient recently reported with bulk carbon .
ROLE OF LEAF LITTER IN INITIATING TRACER TRANSPORT PATHWAYS IN A WOODLAND HILLSLOPE SOIL

It has been suggested that the leaf litter layer influences soil infiltration processes in hillslopes. This paper examines the effect of the presence of the leaf litter layer in an oak woodland on conservative tracer transport measured in situ using time domain reflectometry (TDR) probes. This was done using repeated tracer miscible displacement studies, first with the litter layer intact and then again after removal of the litter layer. Tracer transport, as measured breakthrough curves (BTCs), was characterized using temporal moment analyses. These plot scale studies, performed at a field location in northern California, did not identify consistent changes in tracer transport patterns in the vertical transport plots before and after litter layer removal. In contrast, downslope lateral tracer displacement in the upper 20 cm of the soil did change after litter removal. However, no differences were evident deeper in the soil (30–50 cm) in temporal moments before and after litter removal during lateral tracer transport. This result demonstrates that the litter layer had a localized (near soil surface) influence on lateral transport. This influence may be explained by vertical anisotropy in effective soil hydraulic conductivity on the direction of lateral flow relative to the soil surface in the hillslope plots. It was demonstrated that the litter presence promotes a more vertical direction for the lateral flow in the first 20 cm of the soil. Despite the small changes in the first 20 cm observed in tracer transport after litter removal, the physical presence of the leaf litter layer was not found to be a major influence on tracer transport at the 30- to 50-cm depth in this hillslope soil where most of the lateral flow occurs.
Determination of the Density of Water Emulsions in the Crude Oil Dehydration Process

The salt elimination from produced crude oil is an important stage in oilfield processing and it is considered as a compulsory requirement in the oil industry. In most cases, salt is found a dissolved component in the brine phase in contact with oil. Different compositions of various salts might exist in the brine; however, sodium chloride (NaCl) has the highest fraction in the solution. The water existing in the crude oil is seen as very small drops dispersed in the bulk of oil. In the current study, a simple predictive strategy for density determination of aqueous salty solution in crude oil as a function of salinity (in vol% of sodium chloride concentration), temperature, and pressure is proposed through combination of an Arrhenius-type asymptotic exponential function and the relationship introduced by Spivey et al. (2004). The developed method predicts the amount of salt in the crude oil for temperatures up to 373 K, sodium chloride concentrations up to 250,000 ppm (25% by volume), and maximum pressure of 200 MPa, upon availability of the required input data. Estimations obtained from the proposed approach are found to be in very good agreement with the reported data in the literature so that the absolute error percentage varies in the range of 0.003–1.681%. The technique introduced in this research appears to provide reliable value for the oil engineers to attain a fast estimation of the salt content in the crude oil at various operating conditions without conducting laboratory tests. It is believed that the approach would be user-friendly without complicated computations for chemical and petroleum engineers and researchers. It can be also combined with existing thermodynamic software packages, resulting in an accurate and fast predictive model for practical applications.
1 H nuclear magnetic resonance spectra and conformations of alditols in deuterium oxide

The 1H n.m. r. spectra of the tetritols, pentitols, and hexitols in deuterium oxide have been recorded at 400 MHz, and the shifts and coupling constants obtained by computer simulation of the spectra. The shifts and 3J coupling constants were used to derive conformational data which support previous results on acyclic polyols.
Exciton localization in InGaN quantum well devices

Emission mechanisms of a device-quality quantum well (QW) structure and bulk three dimensional (3D) InGaN materials grown on sapphire substrates without any epitaxial lateral overgrown GaN base layers were investigated. The InxGa1−xN layers showed various degrees of in-plane spatial potential (band gap) inhomogeneity, which is due to a compositional fluctuation or a few monolayers thickness fluctuation. The degree of fluctuation changed remarkably around a nominal InN molar fraction x=0.2, which changes to nearly 0.08–0.1 for the strained InxGa1−xN. This potential fluctuation induces localized energy states both in the QW and 3D InGaN, showing a large Stokes-like shift. The spontaneous emission from undoped InGaN single QW light-emitting diodes (LEDs), undoped 3D LEDs, and multiple QW (MQW) laser diode (LD) wafers was assigned as being due to the recombination of excitons localized at the potential minima, whose lateral size was determined by cathodoluminescence mapping to vary from less than 60 to 300 nm.
Detailed Investigation of Multiphase (Gas–Liquid and Gas–Liquid–Liquid) Flow Behaviour on Inclined Plates

This paper deals with the detailed investigation of homogeneous and heterogeneous liquid flow behaviours as it e.g., appears on distillation column packings. The flow is investigated experimentally as well as numerically. One main aspect is the validation of a multiphase CFD code for this complex application, which offers various difficulties like film flow and film break-up with rivulet and droplet flow. Experimental data of the flow is obtained with optical methods; numerical investigations are carried out with CFX 5, Ansys Inc. The multiphase flow in the first case is composed of one liquid phase and one gas phase (two-phase flow) and in the second case of two immiscible liquid phases and one gas phase (three-phase flow). For validation surface velocities and the spreading of the liquid phases are taken into account as well as morphologies of the flow.
Effect of Temperature, Ionic Strength, Background Electrolytes, and Fe(III) on the Reduction of Hexavalent Chromium by Soil Humic Substances

The rate of hexavalent chromium reduction by soil humic substances (SHSs) was investigated in aqueous solutions where the temperature, ionic strength, background electrolyte, [Fe(III)], and [Cr(III)] were independently varied. Rate experiments were conducted with an excess of SHS over Cr(VI). An Arrenhius plot for the reduction of Cr(VI) by a soil fulvic acid and a soil humic acid indicates that the activation enthalpies for oxidation of these substances are nearly the same (63 ± 1 and 61 ± 3 kJ mol-1, respectively) and the activation entropies are significantly different (−160 ± 5 and −203 ± 9 J mol-1 K-1, respectively). Rates of reduction are not significantly altered due to changes in either background electrolyte or ionic strength. The presence of Cr(III) slightly inhibits the rate of reduction by soil humic acid, but not that of soil fulvic acid. Ferric iron increases the rate of Cr(VI) reduction, even when only a small amount of Fe(III) is added to the system. Fe may enhance the reduction of Cr(VI) .
Two-phase flow in random network models of porous media

To explore how the microscopic geometry of a pore space affects the macroscopic characteristics of fluid flow in porous media, the authors have used approximate solutions of the Navier-Stokes equations to calculate the flow of two fluids in random networks. The model pore space consists of an array of pores of variable radius connected by throats of variable length and radius to a random number of nearest neighbors. The various size and connectedness distributions may be arbitrarily assigned, as are the wetting characteristics of the two fluids in the pore space. The fluids are assumed to be incompressible, immiscible, Newtonian, and of equal viscosity. In the calculation, the authors use Stokes flow results for the motion of the individual fluids and incorporate microscopic capillary force via the Washburn approximation. At any time, the problem is mathematically identical to a random electrical network of resistors, batteries and diodes. From the numerical solution of the latter, the authors compute the fluid velocities and saturation rates of change, and use a discrete time-stepping procedure to follow the subsequent motion. The scale of the computation has so far restricted the authors to networks of modest size (100-400 pores) in two dimensions. Within these limitations,more » the authors discuss the dependence of residual oil saturations and interface shapes on network geometry and flow conditions. « less