Miracle-dz/UniFAR-FTUs huggingface dataset:
Theory of concentration polarization in crossflow filtration

A novel theory is developed for concentration polarization of non-interacting particles in crossflow-filtration systems. This theory reveals that the extent of concentration polarization, as well as the behaviour of the permeate flux, are characterized by an important dimensionless filtration number (NF= 4πa3pΔP/3kT). There is a critical value of the filtration number for a given suspension and operational conditions. When the filtration number is smaller than the critical value, a polarization layer exists directly over the membrane surface and the wall particle concentration is determined by the pressure and temperature. At higher filtration numbers, a cake layer of retained particles forms between the polarization layer and the membrane surface. Mathematical models are constructed for both cases and analytical solutions for the permeate flux are derived. An increase in permeate flux with increasing pressure is predicted for all operational conditions.
Imidazolium chiral ionic liquid derived carbene-catalyzed conjugate umpolung for synthesis of γ-butyrolactones

A serial of imidazolium chiral ionic liquids starting from commercially available (−)-menthol as a chiral pool have been synthesized and successfully used for catalyzing conjugate umpolung of α,β-unsaturated aldehydes to stereoselectively synthesize γ-butyrolactones. The catalytic activities of these ionic liquids are examined and compared. The reaction of trans-cinnamaldehyde and p-methoxycarbonyl benzaldehyde as a model has been investigated in detail, and the reaction conditions have been optimized. Under the selected conditions, the ionic liquid catalyst can catalyze the annulations of trans-cinnamaldehyde with different aromatic aldehydes to afford differently substituted γ-butyrolactones. The recyclability of the ionic liquid catalyst is investigated, and the results have indicated that the catalyst can be recycled six times without obvious activity decreasing.
In‐line analysis of a fluid bed pellet coating process using a combination of near infrared and Raman spectroscopy

Near infrared (NIR) and Raman spectroscopic analyzers applied through an immersion Lighthouse Probe (LHP) were used for simultaneous in‐line monitoring of a fluid bed pellet coating process. Multivariate curve resolution analysis of data, collected from four pilot‐scale batches, has shown that the two techniques deliver complementary information about the process and their combination may be synergistic. This data analysis enabled a much better understanding of some of the process observations and also gave some interesting insights into the best way to use the techniques themselves.
Influence of Homofermentative Lactobacilli on Physicochemical and Sensory Properties of Cheddar Cheese

Cheddar cheeses were produced under pilot plant conditions using a commercial Streptococcus culture amended with one of 10 homofermentative Lactobacillus strains. During the ripening period, pH, acidity, salt, moisture, fat, texture, fissure formation, gas development and sensory status were evaluated. Lactobacillus treated cheese did not differ much from the control in pH and acidity but acidity increased substantially after draining and cheddaring. Lactobacillus numbers increased at all stages as compared with the uninoculated control. High quality Cheddar cheese was produced by L. casei-subsp-casei (119-10/62) and L. casei-subsp-pseudoplantarum (137-10/62) from 7 to 12 vats aged for 2 months at 15°C and for a further 10 months at 7°C or 15°C. Fissure formation was observed in cheese made with L. casei-subsp-rhamnosus, one of the four cultures of L. casei-subsp-casei (LH13) and two of the three strains of L. casei-subsp-pseudoplantarum (83-4-12/62 and L3E). Certain Lactobacillus strains produced cheese with slight flavor defects. Other strains, in particular L. casei-subsp-rhamnosus, contributed to high acidity (72 - 0.89° domic) and low pH (5.2) at salting.
The effective electron affinity estimation from the simultaneous detection of thermally stimulated luminescence and exoelectronic emission. Application to an -alumina single crystal

A method of estimating the electron affinity value of an insulator has been developed. The measurement was carried out from the simultaneous detection of thermoluminescence and thermostimulated exoelectronic emission (TSEE) curves presented by the material. This is possible when the TSEE phenomenon is governed by the thermoionic model and when the electron concentration of the considered trap becomes weaker than that of thermally disconnected traps. The application to an -alumina single crystal shows that the electron affinity can be evaluated as from the thermostimulated peak at 275 K and at from the thermostimulated peak at 440 K. The validity of the model and the signification of the results are discussed.
Effect of preharvest application of calcium on the postharvest physiology of apricot fruit

Abstract The effect of preharvest calcium (Ca) foliar application on ethylene (C2H4) production, respiratory rate, soluble polyuronides, and fruit firmness of ‘Bebekou’ apricot fruits was determined. The study was carried out in two experimental years, 1991 and 1992. Calcium was applied 21, 17, and 13 days before harvest for 1991 at the concentration of 0.5% calcium chloride (CaCl2) each time and 16 and 12 days before harvest for 1992 at the concentrations of 0.8 and 0.7% CaCl2, respectively. Calcium treatment resulted in a 30–76% increase in the Ca content of fruit flesh. Treated fruits had significantly lower C2H4 production rates than control during (i) four (1991) or five days (1992) at 21°C out of the 7‐day period examined immediately after harvest, and (ii) one (1991) or two days (1992) at 21°C out of the seven‐day period examined immediately after a 3rd‐ (1991) or 4th‐week (1992) storage period at 0°C. After harvest, Ca‐treated fruits displayed one day delay to reach the peak rate of C2H4 productio.
Graphite Oxide: Chemical Reduction to Graphite and Surface Modification with Primary Aliphatic Amines and Amino Acids

The chemical reduction of graphite oxide (GO) to graphite by either NaBH4 or hydroquinone and also its surface modification with neutral, primary aliphatic amines and amino acids are described. Treatment of GO with NaBH4 leads to turbostatic graphite that upon calcination under an inert atmosphere is transformed to highly ordered graphitic carbon, while the reduction with hydroquinone yields directly crystalline graphite under soft thermal conditions. On account of the surface-exposed epoxy groups present in the GO solid, its surface modification with neutral, primary aliphatic amines or amine-containing molecules (amino acids and aminosiloxanes) takes place easily through the corresponding nucleophilic substitution reactions. In this way, valuable GO derivatives can be obtained, like molecular pillared GO, organically modified GO affording in organic solvents stable organosols or hydrophilic GO affording in water stable hydrosols and possessing direct cation exchange sites. The potential combination of s.
Facile synthesis of magnetic nanocomposites of cellulose@ultrasmall iron oxide nanoparticles for water treatment

We report a facile in situ approach to synthesize magnetic nanocomposites of cellulose@ultrasmall iron oxide nanoparticles by co-precipitation using ionic liquid as co-solvent for cellulose and iron salt. The as-prepared γ-Fe2O3 nanoparticles showed ultrasmall particle size (∼4.6 nm) and uniform distribution (the standard deviation is less than 10%). The magnetic nanocomposites displayed excellent adsorption efficiency for Pb(II) and methylene blue compared with other reported magnetic materials. The adsorption capacities of the magnetic nanospheres for the removal of Pb(II) and methylene blue were 21.5 and 40.5 mg g−1, respectively. Furthermore, the prepared magnetic nanoadsorbent could be efficiently recycled and reused by applying an external magnetic field. The approach presented in this paper promotes the use of renewable natural resources to prepare a variety of hybrid inorganic–organic materials for the purpose of adsorbents, biomedical and other potential applications.
Etching of high aspect ratio structures in Si using SF6/O2 plasma

We have investigated etching of deep (∼10 μm) submicron diameter holes with high aspect ratios (>10) using plasmas maintained in mixtures of SF6 and O2 gases. The etching experiments were conducted in a low-pressure (5–80 mTorr), high-density, inductively coupled plasma etching reactor with a planar coil. We have studied the effects of pressure, rf-bias voltage, and SF6-to-O2 gas ratio on the etch rate, selectivity, and feature profile using Si wafers patterned with 0.35–0.5 μm diameter holes in a SiO2 mask. Visualization of the profiles with scanning electron microscopy is used in conjunction with plasma diagnostics such as optical emission and mass spectroscopies to understand the key factors that control the anisotropy, selectivity, and etch rate. The F-to-ion flux ratio and F-to-O flux ratio are found to be the important plasma parameters that determine the etch rate and anisotropy. Increasing the SF6-to-O2 ratio in the feed gas increases the F-to-O ratio in the plasma. At high SF6-to-O2 ratio, the ma.
Failure Modes and Mechanisms of DC-Aged GaN LEDs

This paper presents failure modes observed in long-term aging of high-brightness GaN/InGaN LEDs. The blue LEDs submitted to DC aging test present large decrease of emitted optical power and increase of diode reverse leakage current. Increase of parasitic series resistance, suggesting contact degradation, has also been found in stressed sample, together with apparent carrier density increases and reduction of the junction depletion width. Furthermore stressed LEDs present modification of a specific trap property: trap activation energy decreases from 340 meV in the virgin sample down to 75 meV in the stressed sample. Generation of non-radiative recombination centers seems to be one of the dominant failure mechanisms responsible for the observed electrical and optical LED degradations.
Thin-film transistor behaviour and the associated physical origin of water-annealed In–Ga–Zn oxide semiconductor

A transparent In–Ga–Zn oxide semiconductor was thermally annealed in an ambient atmosphere of water vapour and the associated electrical and physical properties of the film were investigated. After annealing in water vapour, the resulting thin-film transistor (TFT) exhibits n-type behaviour with a field effect mobility of 11.4 cm2 V−1 s−1, and an on/off current ratio of 6.65 × 109. The annealing process in water vapour induces changes in the elemental composition and chemical bonding states of Zn and O. These phenomena affect the changes of band alignment including the band gap and conduction band offset (Δ(ECB − EF)) of InGaZnO semiconductors, which is the basis for the improved operation and performance of these TFTs.
Calculation of Lennard‐Jones energies of molecular fluids

In view of the ever increasing awareness of the importance of dispersion forces to chemical solvent effects, reliable liquid Lennard‐Jones (LJ) energies are eagerly required in order to assess the dispersion component of nonionic solvation. For this purpose two major methods of calculating LJ energies—one based on nonpolar gases solubilities and the other on the generalized van der Waals (GvdW) equation of state—are critically reexamined and updated by applying modern liquid state theories. The former method is improved over previous evaluations by including the cavity formation term according to the Boublik–Mansoori–Carnahan–Starling–Leland equation and by a molecular‐based calculation of the solute solvation energy due to both dispersion and induction forces. For the second approach, the attraction parameter of the GvdW equation of state is separated into the contributions of (i) dipole–dipole (permanent and induced) and (ii) dispersion interactions. The first part (i) is treated in the Wertheim theory .
Review of progress in extreme ultraviolet lithography masks

Extreme ultraviolet lithography (EUVL) is a leading next generation lithography technology. Significant progress has been made in developing mask fabrication processes for EUVL. The mask blank for EUVL consists of a low thermal expansion material substrate having a square photomask form factor that is coated with Mo/Si multilayers. SEMI standards are being developed for mask substrates and mounting. Several commercial suppliers are developing polishing processes for LTEM substrates, and they are progressing toward meeting the requirements for flatness, surface roughness, and defects defined in the a draft SEMI standard. One of the challenges in implementing EUVL is to economically fabricate multilayer-coated mask blanks with no printable defects. Significant progress has been made in developing mask blank multilayer coating processes with low added defect density. Besides lowering the added defect density, methods to reduce defect printability, such as defect compensation and buffer layer smoothing, are b.
Fütterungsabhängige Veränderungen der Pansenschleimhaut von Hochleistungskühen im Zeitraum von der Trockenstellung bis acht Wochen post partum

Summary Feed dependent changes of the ruminal mucosa of high producing dairy cows during the dry period and first eight weeks post partum: Rumen mucosa samples were obtained from the ventral sack of the rumen (via rumen fistula) from two groups of Israeli-Holstein-Friesian cows (group A, n = 6; B, n = 5) during the time period from 9 weeks before to 8 weeks after parturition. Both morphometric and histological examinations were performed. Group A cows were switched from a low energy dry period ration to a production ration 14 days prepartum, whereas the ration change for group B occurred at calving. All animals experienced a continuous reduction in rumen mucosa after transition to a dry period ration. The mucosa of group A cows began to proliferate again after the prepartum ration change, but the mucosal degeneration in group B continued until parturition. At the end of the control period (eight weeks post partum) mucosal development in both groups surpassed quantitatively and qualitatively the initial level at the end of lactation. The importance of ration-dependent transformation processes in the rumen for pH-regulation of the forestomach contents and for energy balance (reparatory feeding, postpartum energy deficit) is discussed. Zusammenfassung In zwei Gruppen von Israeli-Holstein-Friesian-Kuhen (A/n = 6; B/n = 5) wurden im Zeitraum von 9 Wochen vor bis 8 Wochen nach dem Partus aus dem ventralen Pansensack Schleimhautproben (via Pansenfistel) entnommen und sowohl morphometrisch als auch histologisch untersucht. Gruppe A wurde 14 Tage a. p., Gruppe B zur Zeit der Kalbung von energiearmem Trockenstehfutter auf Leistungsration umgestellt (Tab. 1). Ergebnisse: Nach Ubergang zur Trockenstehration trat bei allen Tieren ein kontinuierlicher Abbau der Pansenschleimhaut ein (Abb. 1). Wahrend die Mukosa in Gruppe A nach dem prapartalen Futterwechsel wieder zu proliferieren begann, setzte sich in Gruppe B der Abbau bis zum Partus fort (Abb. 1). Am Ende der Kontrollperiode (acht Wochen post partum) ubertraf die Schleimhautentwicklung in beiden Gruppen quantitativ und qualitativ deutlich das Ausgangsniveau zu Laktationsende. Die Bedeutung der futterungsabhangigen ruminalen Umbauvorgange fur die pH-Regulation im Vormageninhalt wie fur den Energiehaushalt (Vorbereitungsfutterung, Energielucke p.p.) wird diskutiert.
A study of Schottky contacts on indium phosphide

The Schottky‐barrier energy φB for Al, Ni, Pd, Co, Au, and Ag contacts on chemically etched 〈100〉 surfaces of both p‐ and n‐type InP was measured and the metallurgical behavior of the contact structures was studied using Auger‐electron spectroscopy. No simple linear relationship could be found between the measured Schottky barrier energies on InP and the work functions or the electronegativities of the contact metals. Therefore, the results could not be explained in terms of the traditional Schottky and Bardeen theories. However, a very well defined relationship was observed between the Schottky barrier energies and the heats of reaction per formula unit ΔHr for the most stable metal phosphides that could be formed between the contact metals and the InP substrate. The contact metals Au and Ag whose phosphides are less stable than InP (i.e., ΔHr >0) produced diffuse interfaces, characterized by extensive outdiffusion of In, and yielded low values of φBp, the Schottky‐barrier energy on p‐type InP; whereas t.
The promotive effect of selenium on plant growth as triggered by ultraviolet irradiation

Selenium is known to be important in antioxidation in human and animals, but little attention has been paid to its role in higher plants. Chemically it is a photovoltaic element, and in order to study its effects on plants, ryegrass (Lolium perenne L.) and lettuce (Lactuca sativa L.) were cultivated in a pot experiment without or with H 2 SeO 4 (0.1 and 1.0 mg Se kg -1 ) under normal light or subjected to UV(B)-irradiation episodes. Without Se addition, UV(B) diminished markedly the yield of lettuce (by 8%) but not that of ryegrass. The lower Se dosage had no effect on yields under normal light conditions, but in combination with UV(B) it enhanced plant growth. This indicates that UV light acted as a trigger for the growth-promoting effect of Se. The higher Se dosage was toxic to plants, but the toxicity was alleviated under UV(B). The positive interaction between the high-energy light and Se was manifested also as increased concentrations of nucleic acids and soluble proteins. The synergistic effect was partly attributable to the antioxidative function of Se, shown as inhibition of lipid peroxidation and promotion of glutathione peroxidase (GSH-Px) activity. Some other possible mechanisms of the positive action of Se are discussed.
Particle shape characterization using morphological descriptors

Two descriptors based on mathematical morphology are described which permit discrimination between convex and concave polygonal shapes which often characterize crystalline particles. Their computation is based on the comparison between the silhouette of the particle and a reference shape. Three reference shapes are discussed: the convex hull, the circle circumscribed to the particle and the equivalent circle.
Determination of Arsenic(III) and Arsenic(V) in Coal and Oil Fly Ashes

Abstract Total arsenic has been determined for fly ashes generated by conventional combustion of pulverized western coal, oil, a coal-oil mixture, a coal-water mixture, and from the fluidized-bed combustion of North Dakota lignite. For most of the ashes the total arsenic levels were between 100 and 200ppm, but the coal-water mixture ash contained 348 ppm. Leaching with 0.5 N H2SO4 or a pH 5 1 M citrate solution resulted in the removal of 78 to 97% of the total arsenic from the particles. This clearly indicates a high surface enrichment of arsenic on the particles, in agreement with numerous previous studies on coal fly ash. The pH5 citrate solution was more effective for the removal of arsenic from the particles without significant oxidative loss of arsenic(III). Speciation of arsenic in the citrate leachate by hydride atomic absorption spectrometry indicated that in most cases less than 2% of the soluble arsenic was arsenic(III). The only exception was the leachate of the coal-oil mixture ash, which cont.
Transition Probabilities in Molecular Collisions: Computational Studies of Rotational Excitation

Exact numerical solutions are presented for the coupled-state formulation of a rigid-rotor–structureless-atom collision, and are compared with qualitative ideas and semiquantitative decoupling approximations for the system. The advantages of using an adiabatic basis for the internal states of the system are demonstrated, in distorted-wave-type computations and in accounting for the direct part and the resonance energies in slow inelastic collisions, in the absence of curve crossing. The diabatic regime is also considered, and a diabatic basis is used for a curve-crossing problem. For these slow, head-on collisions, the Franck–Condon factors are not exponentially small, and significant (>10−1) transition probabilities are possible.
Qualidade física do solo em pomar de laranjeira no noroeste do paraná com manejo da cobertura permanente na entrelinha

The traffic of agricultural machinery and soil compaction occur near the canopy of citrus trees, which increases soil physical restrictions to root growth. Soil management strategies include the use of permanent groundcover in the interrows of orange tree plantations, although the effects of these practices on the soil physical quality are largely unknown. The objective of this study was to assess the impact of groundcover management systems on some indicators of soil physical quality for orange tree orchards. The study was performed in a long-term experiment with 'Pera' orange grafted onto 'Rangpur' lime combined with groundcover systems, established in 1993, in the Alto Parana county, northwestern Parana state, Brazil, in a Typic Paleudult with a sandy surface horizon. Bahiagrass (Paspalum notatum) or perennial peanut (Arachis pintoi) groundcover treatments were compared with the usual management in which weeds are controlled by post-emergence herbicide. The experimental design consisted of randomized blocks with three replications. In May 2003, soil samples were collected from under and between the wheel tracks. The following indicators were assessed in undisturbed soil samples from the mid 0-15 cm layer: water content at field capacity, total porosity and bulk density. The data were used to estimate soil aeration and water storage capacity indicators. Disturbed soil samples were collected in the 0-5 cm and 10-15 cm depths to measure the organic carbon content and calculate the soil organic carbon stratification ratio. The soil aeration capacity, water storage capacity and organic carbon stratification ratio were efficient indicators to evaluate groundcover management systems in citrus. Bahiagrass maintained better soil physical conditions both under and between wheel tracks. The soil physical quality was negatively affected under the wheel tracks on perennial peanut groundcover and under the wheel tracks and between tracks on the usual control of spontaneous vegetation with post-emergence herbicide.
Supramolecular Synthons in Crystal Engineering—A New Organic Synthesis

A crystal of an organic compound is the ultimate supermolecule, and its assembly, governed by chemical and geometrical factors, from individual molecules is the perfect example of solid-state molecular recognition. Implicit in the supramolecular description of a crystal structure is the fact that molecules in a crystal are held together by noncovalent interactions. The need for rational approaches towards solid-state structures of fundamental and practical importance has led to the emergence of crystal engineering, which seeks to understand intermolecular interactions and recognition phenomena in the context of crystal packing. The aim of crystal engineering is to establish reliable connections between molecular and supramolecular structure on the basis of intermolecular interactions. Ideally one would like to identify substructural units in a target supermolecule that can be assembled from logically chosen precursor molecules. Indeed, crystal engineering is a new organic synthesis, and the aim of this article is to show that rather than being only nominally relevant to organic chemistry, this subject is well within the mainstream, being surprisingly similar to traditional organic synthesis in concept. The details vary because one is dealing here with intermolecular interactions rather than with covalent bonds; so this article is divided into two parts. The first is concerned with strategy, highlighting the conceptual relationship between crystal engineering and organic synthesis and introduces the term supramolecular synthon. The second part emphasizes methodology, that is, the chemical and geometrical properties of specific intermolecular interactions.