Miracle-dz/UniFAR-FTUs huggingface dataset:
Stimulated Intrinsic Recombination Processes in II–VI Compounds†

The intrinsic recombination processes are investigated in highly excited II–VI compound semiconductors which involve the following scattering processes: the exciton-exciton scattering (P2 line), the exciton-electron or -hole scattering, and the sattering of an exciton by emission of a longitudinal optical phonon. From the stationary rate equations the laser threshold and the maxima of the spontaneous and stimulated emission for the various processes are determined. Experimental investigations of these emission processes are carried out for CdS platelets, ZnO and ZnTe crystals. Good agreement between experimental results and theoretical predictions for the temperature dependences of the laser thresholds, and of the emission maxima is obtained. In stark angeregten II–VI-Halbleitern werden die intrinsischen Rekombinationsprozesse untersucht, denen folgende Streuprozesse zu Grunde liegen: die Exziton-Exziton-Streuung (P2-Linie), die Exziton-Elektron oder -Loch-Streuung und die Streuung eines Exzitions unter Emission eines longitudinalen optischen Phonons. Aus den stationaren Bilanzgleichungen werden die Laserschwelle und die Maxima der spontanen und stimulierten Emission der verschiedenen Prozesse bestimmt. Experimentelle Untersuchungen dieser Emissionsprozesse an CdS-Plattchen, ZnO- und ZnTe-Kristallen werden durchgefuhrt. Gute Ubereinstimmung zwischen Experiment und Theorie wird fur die Temperaturabhangigkeiten der Laserschwellen und der Emissionsmaxima erhalten.
Generalized entering coefficients: A criterion for foam stability against oil in porous media

The unique mobility-control properties of foam in porous media make it an attractive choice as an injection fluid for enhanced oil recovery. Unfortunately, in many cases oil has a major destabilizing effect on foam. Therefore, it is important to understand how oil destabilizes foam and what surfactant properties lead to increased stability against oil. To explain the stability of foam in porous media in the presence of oil, we generalize the ideas of spreading and entering behavior using Frumkin-Deryaguin wetting theory. This formulation overcomes the inherent deficiencies in the classical spreading and entering coefficients used to explain foam stability against oil. We find that oil-tolerant foam can be produced by making the oil surface ``water wet``. To test our theoretical ideas, we measure foam-flow resistance through 45--70 {mu}m glass beadpacks, surface and interfacial tensions, and disjoining pressure isotherms for foam and pseudoemulsion films for a variety of surfactant/oil systems. Most notably, we measure pseudoemulsion-film disjoining pressure isotherms for the first time and directly establish that pseudoemulsion film stability controls the stability of the foam in the systems we tested. Moreover, we demonstrate the correspondence between stable pseudoemulsion films, negative entering behavior, and oil-tolerant foams.
Determination of Carbendazim in Water, Soil and Sediment Samples by RPLC with and Without Column Switching and Various Spectrometric Detection Modes

Abstract This study presents the developed and applied methods for the determination of carbendazim in environmental samples originating from several field studies. For water samples sample pretreatment consisted of a solid phase extraction (SPE) on cartridges packed with 200 mg SDB-1. In case of solid samples the performance of microwave assisted solvent extraction (MASE) and classical ultrasonic extraction with acetone-ethyl acetate were studied. The latter technique was selected because of the reduced time of manual operations. Instrumental analysis of extracts of water samples was performed on-line with coupled column reversed phase liquid chromatography (LC/LC) and UV detection (280 nm) allowing to assay carbendazim to a level of at least 0.1 μg/l. Improved column life time was obtained by performing the favorable LC separation of carbendazim at high pH on newly developed 5 μm Extend-pH bidentate C18 material. The combination of a short column packed with 5 μm Inertsil ODS-5 and a mobile phase at low pH material was most adequate as the regards the robust and fast processing of extracts of solid samples and allowed in most cases the screening of carbendazim in soils and sediments to a level of 10μg/kg. The developed procedures yield overall recoveries for carbendazim of 101, 80 and 71 % in water (levels, 0.1—1.2 μg/l: n=12), soil (levels, 10 and 100 μg/kg; n=22) and sediments (levels, 10 and 100 μg/kg; n=11), respectively, with a repeatability and reproducibility below 7 % for all method/matrix combinations. Soil samples with aged residues (level, 100 μg/kg; n=10) provided an overall recovery of 71% and no significant decrease of carbendazim was observed during nine weeks of storage in the refrigerator.
Identificação de extratos etanólicos de madeiras utilizando seu espectro eletrônico de absorção e análise multivariada

The application of multivariate analysis to spectrophotometric (UV) data was explored for distinguishing extracts of cachaca woods commonly used in the manufacture of casks for aging cachacas (oak, cabreuva-parda, jatoba, amendoim and canela-sassafras). Absorbances close to 280 nm were more strongly correlated with oak and jatoba woods, whereas absorbances near 230 nm were more correlated with canela-sassafras and cabreuva-parda. A comparison between the spectrophotometric model and the model based on chromatographic (HPLC-DAD) data was carried out. The spectrophotometric model better explained the variance data (PC1 + PC2 = 91%) exhibiting potential as a routine method for checking aged spirits.
Ions at the Liquid/Vapor Interface of Methanol

We studied ions at the liquid/vapor interface of methanol using classical molecular dynamics techniques. Polarizable potential models were used to describe interactions among species. We characterized the transport mechanism of an iodide anion across the methanol interface. The computed potential of mean force showed a relatively small minimum well depth (i.e., −0.60 kcal/mol) located inside the Gibbs dividing surface. During the constrained mean force simulations, we found the iodide anion carrying some methanol molecules with it as it crossed the dividing interface. The computed density profiles of the salt NaI methanol interface indicated that the iodide anions were found nearer to the interface than the sodium cations, and no well-defined maxima were found for neither ion near the interface. By comparing this result with the corresponding result obtained from a simulation of the NaI saltwater interface, we can conclude that the probability of finding iodide anions at the liquid/vapor of water interfac.
Effects of different cooking methods on the vitamin C content of selected vegetables

Purpose – Vegetables are rich in vitamin C, but most of them are commonly cooked before being consumed. The objective of the present study was to evaluate the effects of three common cooking methods (i.e. steaming, microwaving, and boiling) on the vitamin C content of broccoli, spinach, and lettuce.Design/methodology/approach – 100 g of homogeneous pieces of broccoli, spinach, and lettuce was separately processed for 5 minutes by steaming, microwaving, and boiling. A simple UV analytical method was employed to determine the vitamin C content of the vegetables.Findings – Loss of vitamin C in broccoli, spinach, and lettuce during steaming was 14.3, 11.1, and 8.6 per cent, respectively, while the loss of vitamin C during boiling was 54.6, 50.5, and 40.4 per cent, respectively. During microwaving, loss of vitamin C in broccoli, spinach, and lettuce was 28.1, 25.5, and 21.2 per cent, respectively.Practical implications – This study shows that any raw vegetable contains the highest content of vitamin C compared.
The Recovery of Indium Metal from ITO-scrap using Hydrothermal Reaction in Alkaline Solution

E-mail: parkjc@silla.ac. krReceived June 13, 2011, Accepted August 19, 2011Key Words : Recovery, Indium, ITO-scrap, Hydrothermal reaction, Alkaline solutionIndium element is very rare one and tend to occur at lowconcentrations in sulfide minerals rather than as oxides.Indium (0.21 ppm) is similar in abundance to Sb and Cd,whereas Tl (0.7 ppm) is close to Tm and somewhat lessabundant than Mo, W, and Tb (1.2 ppm). Indium, like Ga, isnormally recovered by electrolysis after prior concentrationin processes leading primarily to other elements (Pb/Zn). Indium metal is soft, silvery one with a brilliant lustre, andused to protect bearings against wear and corrosion. Indiummetal frequently uses in low-melting alloys and in electronicdevices as its low melting-point ( ≈ 156
Synthesis of high-quality carbon nanotube fibers by controlling the effects of sulfur on the catalyst agglomeration during the direct spinning process

The effects of sulfur on the size of iron catalyst particles and synthesized carbon nanotubes (CNTs) were investigated during the direct spinning of CNT fibers. CNT fibers containing mainly double-walled CNTs (DWCNTs) 5–10 nm in diameter were synthesized from acetone, ferrocene, and thiophene, whereas CNT fibers containing mainly single-walled CNTs (SWCNTs) 1–1.5 nm in diameter were obtained from methane, ferrocene, and sulfur. The differences in the products arose from the anti-agglomeration effects of the sulfur atoms, which were adsorbed onto the surfaces of the iron catalyst particles, as indicated by direct experimental evidence. A model for the interplay between sulfur atoms and the iron catalyst particles was proposed based on these results, and experimental confirmation of this model was sought by modulating the sulfur injection time into the reactor at different temperatures. This simple experimental modification was used to control the majority of CNTs in the CNT fibers synthesized from SWCNTs, through DWCNTs, and finally to multi-walled CNTs (MWCNTs), with corresponding IG/ID ratios that varied from 26.9 to 1.5.
Surface charge sensing by altering the phase transition in VO2

Detection of surface charges has various applications in medicine, electronics, biotechnology, etc. The source of surface charge induction may range from simple charge-polarized molecules like water to complicated proteins. It was recently discovered that surface charge accumulation can alter the temperature at which VO2 undergoes a Mott transition. Here, we deposited polar molecules onto the surface of two-terminal thin-film VO2 lateral devices and monitored the joule-heating-driven Mott transition, or conductance switching. We observed that the power required to induce the conductance switching reduced upon treatment with polar molecules and, using in-situ blackbody-emission direct measurement of local temperature, we show that this reduction in power was accompanied by reduction in the Mott transition temperature. Further evidence suggested that this effect has specificity to the nature of the species used to induce surface charges. Using x-ray absorption spectroscopy, we also show that there is no det.
Infrared spectroscopy of Si(111) surfaces after HF treatment: Hydrogen termination and surface morphology

Polarized internal reflection spectroscopy has been used to characterize HF‐treated Si(111) surfaces. The silicon‐hydrogen stretching vibrations indicate that the surface is well ordered, but is microscopically rough, with coupled monohydride, dihydride, and trihydride termination.
RESPONSE OF TURFGRASS GROWTH IN A BLACK CHERNOZEMIC SOIL AMENDED WITH MUNICIPAL SOLID/BIOSOLID WASTE COMPOST

High transportation cost is a barrier which prevents land application of compost far away from where the compost is produced. As a result, use of compost in lawns is becoming a popular alternative in municipalities where compost is produced from municipal solid/biosolid waste. A four-year (2002 to 2005) field experiment was conducted on turfgrass [20% Kentucky Blue (Poa pratensis L.) + 80% Creeping Red Fescues (Festuca rubra L.)] grown on a Black Chernozem soil near Edmonton, Alberta, Canada, to determine the effect of rate and frequency of spring application of compost (prepared from soild/biosolid waste of city of Edmonton) on biomass, sward color, concentration and uptake of nutrients of sward, and soil chemical properties. There were three compost treatments: 50 Mg ha−1 annual; 100 Mg ha−1 (1st year) + 50 Mg ha−1 (2nd year) split, and 150 Mg ha−1 once in three years (2002, 2003 and 2004) applications. In addition, there were check (no fertilizers or compost) and annual nitrogen-phosphorus-potassium-sulfur (NPKS) fertilizer application (100 kg N + 20 kg P + 42 kg K + 20 kg S ha−1 annual) treatments. In the fourth year (2005), residual effect of applied compost on turfgrass growth was determined. Annual application of compost at 50 Mg ha−1 had more green color of leaf, and higher sward N concentration and biomass production of turfgrass for prolonged periods than the check treatment. In comparison with annual application, high initial compost and split applications generated greater turfgrass growth only in the first two years, but produced higher cumulative biomass over the three- or four-year period. Both annual and cumulative biomass yields were highest in treatments receiving NPKS fertilizers. After four growing seasons, there was no residual mineral N in soil from both compost and NPKS fertilizer, and no residual sulfate-S in soil from NPKS fertilizer treatments. The amounts of extractable P and exchangeable K in soil were greater in compost treatments than in the NPKS fertilizer treatment. There was downward movement of extractable P into the 15–30 cm soil depth in one-time initial and split compost and NPKS fertilizer treatments, and of sulfate-S in all compost treatments. In conclusion, annual application of compost in spring at 50 Mg ha−1 is recommended for sustainable color and growth of turfgrass.
DNA three-way junction–ruthenium complex assemblies

Three-way junction building blocks were designed to construct novel 2D ruthenium–DNA assemblies. Discrete three-branched DNA motifs were formed with 1 to 3 sticky ends of 14-, 20- and/or 24-mer nucleotides. Hybridization with the complementary mono Ru–DNA conjugates afforded the formation of a family of three-way assemblies with 1 to 3 peripheral ruthenium complexes. The use of sticky ends of different lengths allowed us to modulate the number of metallic complexes introduced and also to extend the structure. Indeed, our construction strategy associated with the use of bis ruthenium–DNA conjugates permitted the assembly of double three-way junctions linked by DNA duplexes with or without ruthenium complexes in their centre.
AVALIAÇÃO DA BIODEGRADABILIDADE ANAERÓBIA DE LIXIVIADOS DE ATERRO SANITÁRIOS

The objectives of this article were to investigate the favorable environment and operational conditions to the development of the anaerobic biodegradability test for landfill leachate. The evaluated conditions were the relation food/microrganismo (A/M), seed acclimatization, and toxicity due to high ammonia concentration. The results indicated that A/M relation equivalent to 0,45 was presented as most favorable to the accomplishment of the test, and that the seed used presented good capacity of adaptation to the leachate, not demanding previous acclimatization. The leachate in question presented relatively low anaerobic biodegradability, and associated to the results of previous studies of aerobic biodegradability suggest that a significant fraction of organic substance is refractory to the aerobic and anaerobic metabolism, indicating that the physical-chemical treatment must be used as form of pre or post-treatment.
Variability in Elemental Accumulations Among Leafy Brassica oleracea Cultivars and Selections

Abstract The vegetable brassicas are consumed in part for their nutritional values of calcium (Ca), magnesium (Mg), potassium (K), iron (Fe), and zinc (Zn). However, information on the genetic variability of elemental accumulation within kale and collards (Brassica oleracea L. var. acephala DC) is limited. Therefore, 22 kale and collard cultivars and selections suitable for the northeastern United States were field grown under similar fertility regimes over two years and evaluated for elemental accumulation. Leaf tissues were analyzed using inductively coupled argon plasma–atomic emission spectrometry. Significant variability among cultivars and selections was observed for tissue Ca, Mg, K, Fe, and Zn. On average, a two-fold difference in elemental accumulation among the cultivars and selections was measured. Tissue Ca levels ranged from 1.2 (“Crimson Garden”) to 3.1% (“NZ Thousand Head”), tissue Mg ranged from 0.3 (“Crimson Garden”) to 0.6% (“NZ Thousand Head”), tissue K ranged from 2.1 (“NZ Thousand Head”) to 3.5% (30665-96G11), tissue Fe ranged from 53.1 (“Winterbor F1”) to 114.2 mg/kg (“Giant Jersey Kale”), and tissue Zn ranged from 29.1 (“Shetland”) to 71.9 mg/kg (“Redbor F1”). Significant year-to-year variability occurred for Ca, Mg, Fe, and Zn accumulation. Despite these yearly changes, ranking of the cultivars and selections for elemental accumulation, as determined by Spearman's rank correlation coefficient, did not change from year 1 to year 2. Overall, the cultivar with the highest elemental leaf accumulation was “Redbor F1”. Information on genotypic variability for elemental accumulation may be important for producers and consumers looking to select kale and collards with higher nutritional levels of beneficial dietary elements.
The nutritive value of field peas (Pisum sativum) in an oat-based diet for laying hens.

In an experiment with laying hens, an oat-based diet containing one-third ground field peas (Pisum sativum) supported egg production which was only half that on a control diet containing fishmeal. Either the addition of methionine to the diet or processing the peas by heating and flaking, increased egg production to about three-quarters of the control output. Methionine supplementation in addition to heat processing of the peas allowed full egg production.
The Growth of an Electron Avalanche Retarded by its Own Space Charge

In this paper calculations are given showing how the ionization coefficient α, and the total multiplication in the avalanche, vary with the distance travelled when the positive ions formed have an appreciable effect. The time taken for an avalanche to develop is also worked out. Plane parallel geometry is considered, and two important cases are treated, namely constant field at the electrodes, or constant potential across them. A simple and exact solution is obtained for constant field, and an approximate solution for constant potential. The latter shows that α may decrease or increase depending on the initial conditions, and that it tends finally to a constant value. The equations are general and thought to be of wide application.
Time-resolved study of pulsed Ar–N2 and Ar–N2–H2 microwave surfaguide discharges using optical emission spectroscopy

Pulsed surfaguide microwave discharges operating at 2.45 GHz in several Ar–N2 and Ar–N2–H2 gas mixtures are studied using optical emission spectroscopy. Time-resolved measurements of Ar, N2, , N, and H emission lines are presented. The gas temperature, and N2 rotational and vibrational temperatures are also analyzed. Various discharge conditions, dependent on the applied power, discharge pressure, nitrogen and hydrogen content are examined. Time-resolved measurements confirm that N2 dissociation in the discharge depends mainly on the presence of nitrogen ions (dissociative recombination). Gas temperature is found to be a power-dependent parameter, whereas vibrational temperature is mainly determined by nitrogen content and by the presence of H2 in the mixture. Our data show that a negligible (∼0.2%) addition of H2 dramatically changes the N2 dissociation mechanism, as well as the time evolution of the emission lines during the pulse. These effects are explained by the disappearance of generation due to the quenching of the N2(A) metastable level by molecular hydrogen.
Specific Near‐IR Absorption Imaging of Glioblastomas Using Integrin‐Targeting Gold Nanorods

Molecular imaging using nanoprobes with high resolution and low toxicity is essential in early cancer detection. Here we introduce a new class of smart imaging probes employing PEGylated gold nanorods (GNRs) conjugated to cRGD for specific optical imaging of αvβ3 integrins from glioblastoma. GNRs exhibiting an optical resonance peak in the near‐infrared (NIR) region were synthesized using the seed‐mediated growth method. CTAB (cetyl trimethylammonium bromide) bilayer on the GNRs was replaced with a biocompatible stabilizer, heterobifunctional polyethyleneglycol (COOH‐PEG‐SH). Further, the carboxylated GNRs (PGNRs; PEG‐coated GNRs) were functionalized with cRGD using EDC‐NHS chemistry to formulate cRGD‐conjugated GNRs (cRGD‐PGNRs) for αvβ3 integrins. In order to assess the potential of the cRGD‐PGNRs as a targeted imaging probe, we investigated their optical properties, biocompatibility, colloidal stability and in vitro/in vivo binding affinities for cancer cells. Consequently, cRGD‐PGNRs demonstrated excellent tumor targeting ability with no cytotoxicity, as well as sufficient cellular uptake due to stable and prolonged blood circulation of cRGD‐PGNRs.
Efficient Synthesis of 3-R-Boc-amino-4-(2,4,5-trifluorophenyl)butyric Acid

Abstract 3-R-Boc-amino-4-(2,4,5-trifluorophenyl)butyric acid (9) was obtained from L-methionine in six steps with a total yield of 32%. The α-amino acid segment of L-methionine was transferred to chiral aziridine by amino protection, reduction, hydroxyl derivation, and cyclization. After ring opening of 2,4,5-trifluoro-phenyl magnesium bromide, the methylthiomethyl group was then hydrolyzed to β-amino alcohol and oxidized to the target β-amino acid. GRAPHICAL ABSTRACT
Measurement of Three-Dimensional Solubility Parameters of Nonyl Phenol Ethoxylates Using Inverse Gas Chromatography

Abstract Reported here is a novel technique, based on inverse gas chromatography (IGC), to measure the three-dimensional solubility parameters of nonionic surfactants—nonyl phenol ethoxylates—with different ethylene oxide chain lengths at two different temperatures. These solubility parameters can then be used to characterize the relative oil and water affinities of the surfactant. The three-dimensional solubility parameters of these surfactants were determined on the basis of the measured interaction parameters and known three-dimensional solubility parameters of the solvents (probe molecules) used in the IGC experiments. In particular, it was assumed, based on the regular solution theory, that the occurrence of a zero or negative interaction parameter is evidence of thermodynamic compatibility of the particular probe and surfactant. The three-dimensional solubility parameters of the surfactant are obtained by averaging the corresponding values of the compatible low-molecular-weight probe substances. In this way, combination of the lattice model of solutions (which allows negative enthalpies of solution) and the solubility parameter theory (which accounts for endothermic solutions only) is not required. As a result, measured negative interaction parameters are not a stumbling block for obtaining Hildebrand and three-dimensional solubility parameters. The method described is applicable to measurement of three-dimensional solubility parameters of all materials. Surfactants were used here as a convenient illustration only.