Miracle-dz/UniFAR-FTUs huggingface dataset:
Radar and Lightning Observations of Deep Moist Convection across Northern Alabama during DC3: 21 May 2012

AbstractThe Deep Convective Clouds and Chemistry (DC3) experiment seeks to understand the kinematic and microphysical controls on the lightning behavior of deep moist convection. This study utilized multiple dual-polarization Doppler radars across northern Alabama to quantify microphysical and kinematic properties and processes that often serve as precursors to lightning, such as the graupel echo volume, graupel mass, and convective updraft volume. The focus here was on one multicellular complex that occurred on 21 May 2012 in northern Alabama during DC3. The graupel echo volume and the graupel mass in the charging region correlated well with the total lightning flash rate (FR), and even better than the updraft volumes and maximum updraft velocities. The flash length scales (LS) and flash areas were generally anticorrelated to the FR, while it was correlated to the nonprecipitation ice volume. More specifically, the presence of smaller flashes was associated with a stronger lower positive charge region ca.
Characterizing the soil physical condition in reduced tillage systems for winter wheat on a fine sandy loam using small cores

A tillage study was conducted in Prince Edward Island with winter wheat (Triticum aestivum L.) over two seasons on a Gowanbrae light fine sandy loam, a Humo-Ferric Podzol. One-pass mouldboard ploughing, shallow tillage using a rotary harrow, and direct drilling were evaluated for their effects on crop productivity and soil physical properties. Direct drilling increased plant survival but not grain yield in the first year compared to the other tillage systems. Leaf diseases significantly reduced crop performance under shallow tillage and direct drilling in the second year. None of the tillage systems had adverse effects on soil strength at field capacity over the 0- to 350-mm soil profile depth, as penetrometer resistance values were < 1.5 MPa. Differences in soil macro-aggregation and organic carbon distribution between tillage systems were noted in the Ap horizon. Sequential measurements on soil cores equilibrated at 6 kPa tension for macropore volume, air permeability at low air pressure (0.25 kPa), oxy.
2,3- and 4,5-Secodopa, the Biosynthetic Intermediates Generated from L-Dopa by an Enzyme System Extracted from the Fly Agaric, Amanita muscaria L., and Their Spontaneous Conversion to Muscaflavin and Betalamic Acid, Respectively, and Betalains

An enzyme is extracted from the red peel of Amanita muscaria which cleaves the C(2)–C(3) and the C(4)–C(5) bond of the aromatic ring of L-dopa (1) to form a mixture of 4,5-secodopa (= salt of 6-amino-2-hydroxy-4-(2′-oxoethylidene)hept-2-enedioic acid; 2) and 2,3-secodopa ( = salt of 7-amino-5-formyl-2-hydroxyocta-2,4-dienedioic acid; 3), two hitherto hypothetical biosynthetic intermediates (see Scheme). Though isolation of these products has not been possible, structural evidence is inferred from reaction products, kinetics, and spectroscopical characteristics in comparison with known compounds. Secodopas 2 and 3 are characterized in dilute solution by HPLC and UV/VIS spectroscopy (anions; λmax 424 and 414 nm, resp., ϵ420 = 25500; on acidification, shift to 380 and 372 nm, resp.). They cyclize without enzyme catalysis, optimally at pH 4.5–5; 3 produces muscaflavin (5) and 2 betalamic acid (4). The products arc identified by direct comparison with authentic samples in HPLC, by 1H-NMR of 5, and by condensation of 4 with L-proline to form the well known betalain indicaxanthin (7). The enzymatic conversion of L-dopa (1) via2 to betalamic acid (4; (S)) and its condensation with L-proline leads to pure natural indicaxanthin (7; (2S,115)); correspondingly, the enzymatic conversion of D-dopa to (R)-betalamic acid and its condensation with L-proline produces isoindicaxanthin ((2S,11R)) which is unknown in nature. Particularly relevant is the fact that the same enzyme cleaves pyrocatechol to produce a solution of the enolate form of the known 2-hydroxy-6-oxohexa-2,4-dienoate (secopyrocatechol; 9; see Fig. 5). Dissociation constants of the corresponding enolic functions in the cleavage products are determined by spectrometric titration and compared to those of known systems.
Gradients in valence bond theory

A gradient method for general valence bond wave functions is presented. The electronic energy is used as a Lagrange multiplier. The derivatives of the normalization and of the first- and second-order cofactors present in the energy expression have to be evaluated, giving rise to first-, second-, and third-order cofactors. This evaluation is done using an extension of methods described previously. The use of gradients is illustrated with some calculations on organic molecules, viz. ethene, 1, 4-butadiene, and benzene.
Defects and dislocations in MgO: Atomic scale models of impurity segregation and fast pipe diffusion

Dislocations are known to influence the formation and migration of point defects in crystalline materials. We use a recently developed method for the simulation of the cores of dislocations in ionic materials to study the energy associated with the formation of point defects close to the core of a ½ {10} edge dislocation in MgO. These are then compared with the energies for the same point defects in otherwise perfect MgO. It is found that all of the defect species are bound to the dislocation core, with binding energies of between 1.5 and 2.0 eV. Vacancies are found to be most stable when they remove under-coordinated ions at the tip of the extra half plane, while the impurities are most stable within the dilatational stress field below the glide plane. By mapping the distribution of energies for point defects around the dislocation line we reveal the coupling between the effective point defect size and the stress field associated with the dislocation. We also examine the energy barrier to diffusion of vacancies along the dislocation line and find that vacancy migration along the dislocation line will be substantially enhanced compared to migration through the dislocation-free crystal structure. Activation energies are 0.85–0.92 of the barrier in the perfect crystal, demonstrating the importance of pipe diffusion along extended defects for low temperature mobility in ionic materials.
Local Structure of Alkaline‐Earth Boroaluminate Crystals and Glasses: II, 11B and 27Al MAS NMR Spectroscopy of Alkaline‐Earth Boroaluminate Glasses

11B and 27Al magic angle spinning nuclear magnetic resonance (MAS NMR) spectra of alkaline-earth boroaluminate glasses show that the structure of these glasses are far more complicated than previously thought. The relative concentrations of 3- and 4-coordinated boron vary as found by previous investigators using continuous-wave NMR methods, but the 27Al NMR spectra indicate the presence of Al in 4-, 5-, and 6-fold coordination, in contrast to previous assignments. Analysis of the data based on local charge balance considerations provides a qualitative model that correctly predicts compositional variations of the NMR peak intensities and 27Al chemical shifts for a wide range of boroaluminate glass compositions.
Coupled-cluster reference values for the GW27 and GW100 test sets for the assessment of GW methods

The vertical ionisation energies of the molecules of the GW27 (27 molecules) and GW100 (100 molecules) test sets are computed in a polarised triple-zeta-valence basis set in the framework of coupled-cluster theory with single, double, and non-iterative triple substitutions. The molecular geometries were kept fixed to those of the two test sets. To demonstrate the usefulness of the coupled-cluster reference values, they are compared with quasi-particle energies obtained in the G0W0 approximation for functionals commonly used in Kohn–Sham density-functional theory (DFT). Furthermore, an approximation is assessed, in which only exchange contributions are added to the DFT orbital energies.
Quasi-Living trans-1,4-Polymerization of Isoprene by Cationic Rare Earth Metal Alkyl Species Bearing a Chiral (S,S)-Bis(oxazolinylphenyl)amido Ligand

A series of chiral mononuclear dialkyl complexes [(S,S)-BOPA]Ln(CH2SiMe3)2 (1, 2) (BOPA = (S,S)-bis(oxazolinylphenyl)amido; Ln = Sc (1); Ln = Lu (2)) and binuclear alkyl complexes [ο-(S)-OPA–C6H4–(CH2SiMe3)C═N–CH(iPr)CH2–O]Ln(CH2SiMe3)}2 (3,4) (OPA = (oxazolinylphenyl)amine; Ln = Y (3); Ln = Tm (4)) have been synthesized in moderate yields via one-pot acid–base reactions by use of the tris(trimethylsilylmethyl) rare earth metal complexes with the chiral tridentate (S,S)-bis(oxazolinylphenyl)amine ligand. In the presence of activator with or without a small amount of AliBu3, the dialkyl complexes 1 and 2 exhibit very high activities (up to 6.8 × 105 g molLn–1 h–1) and trans-1,4-selectivity (up to 100%) in the quasi-living polymerization of isoprene, yielding the trans-1,4-PIPs with moderate molecular weights (Mn = (0.2–1.0) × 105 g/mol) and narrow molecular weight distributions (Mw/Mn = 1.02–2.66).
Study on the Preparation of Starch-Based Polyampholyte and Slow Release Performance

The starch-based polyampholyte (SPAM) was synthesized by graft copolymerization of starch with acrylamide (AM) and acrylic acid (AA). The structural and chemical characteristics of the product, as well as its efficiency in slowing the nitrogen release and water evaporation in soil were examined. The slow-release effect of SPAM was better than starch, starch-g-SPAC (Sodium polyacrylate) and starch-g-PVAC (Polyvinyl ammonium chloride) for urea release, particularly when the pH of SPAM solution was equal to 5(approached or equaled to isoelectric point, IEP). These studies showed that the product with good slow-release and being environmentally friendly is biodegradable carrier materials.
Hydrothermal liquefaction of Chlorella pyrenoidosa in water and ethanol.

This study aimed at converting low lipid content microalgae (Chlorella pyrenoidosa) to biofuels via hydrothermal liquefaction (HTL). In this article, ethanol was introduced as a solvent for the HTL process. The products of the HTL process were separated into gas, residue, bio-crude, and volatile components. The effects of using ethanol as the solvent are discussed in detail and compared with the traditional HTL process. Preliminary results showed that HTL with ethanol, compared with using water as the solvent, resulted in higher bio-crude yield (51.1%) with better thermal stability (95% acetone soluble after drying at 105°C), along with lower gas and residue yields (1.4% and 14.2%, respectively). The effects of operating parameters, including feedstock load ratio, solid load ratio, and initial pressure, on processing pressures and product yields were investigated. Experimental results indicated that HTL with a high feedstock load ratio increased the residue yield. Compared with water, ethanol was more suitable for HTL under high solid load ratio conditions. HTL of Chlorella pyrenoidosa with water as the solvent was fairly insensitive to the investigated processing parameters within the measuring ranges. Yields of bio-crude, gas, and residue had average values of 40.5% ±1.7%, 6.3% ±0.7%, and 20.8% ±2.9%, respectively.
Microwave saturation of EPR spectra of oxidised coal

Microwave saturation of multi-component EPR spectra of oxidized lignite Mequinenza (Spain) with a carbon content of 65.1 wt % and with a high sulphur content of 10.3 wt % was studied. The coal was oxidized with nitric acid (NHO3), peroxyacetic acid (PAA), and in O2/Na2CO3 system. Three different groups of paramagnetic centres exist in the coal samples analyzed. The EPR spectrum of the demineralised coal was a superposition of broad Gauss (ΔBpp = 0.75 mT), broad Lorentz 1 (ΔBpp = 0.42 mT) and narrow Lorentz 3 lines (ΔBpp = 0.08 mT). The three EPR components with linewidths: 0.58–0.77 mT (Gauss line), 0.30–0.39 mT (Lorentz 1 line) and 0.05–0.06 mT (Lorentz 3 line) were recorded for the oxidized coal. The g-values were obtained for the samples studied in the ranges 2.0043–2.0046 (Gauss lines), 2.0035–2.0038 (Lorentz 1 lines) and 2.0032–2.0034 (Lorentz 3 lines). The broad Gauss and Lorentz 1 lines saturate at low microwave powers. The narrow Lorentz 3 lines of demineralised coal were not saturated at microwave power from the range considered. After the coal oxidation with HNO3, PAA and in O2/Na2CO3 system, the microwave saturation of the narrow Lorentz 3 lines was also observed, which indicated a degradation of the multi-ring aromatic structures upon oxidation.
Spectrophotometric Analysis of Water Ice Regions on the Surface of the Comet 9P/Tempel 1

Introduction: The Deep Impact spacecraft encountered Comet 9P/Tempel 1 on July 4th, 2005 [1]. We analyzed publicy available data obtained by the HRI (High Resolution Imager) consisting of a telescope serving both a camera and an imaging spectrometer in the infrared range [2]. We have selected data taken before the impact, where the nucleus is resolved and has a maximum spatial resolution of 120 m per pixel. We started this activity in preparation of the Rosetta rendez-vous with comet 67P/ChuryumovGerasimenko in the second half of 2014. Rosetta carries the VIRTIS imaging spectrometer [3] which has characteristics similar to those of HRI, and will provide large amounts of data, with resolutions never achieved before. Thus the goal of this work is to apply to the HRI data set the unmixing algorithms we intend to use to interpret the 67P/C-G nucleus spectra data and thus retrieve information on the water ice abundance and emplacement on the surface of 9P/Tempel1. Radiance calibrated data from the HRI camera and spectrometer were geometrically corrected and reduced to I/F. Applying the Hapke model [4] in a similar manner as described in [5] we are able to constrain the amount of water ice and the regolith grain size for the ice-rich regions of the comet. Two mixing modalities are investigated: areal and intimate. As endmemebers for the spectral mixing we have considered pure water ice and an average spectra from the non-icy regions of the comet. Adopting the areal mixing we obtain from the spectral fits an average grain size of 30±20 μm in diameter with a percentage of water ice of 0.4±0.2%. In the case of intimate mixing we obtain a grain size of 70±40 μm with a percentage of water ice of 1.0±0.5%. The spectra corresponding to the icy regions are wellfitted with both mixing methods.
CANOLA OIL PRODUCTION AND NUTRIENT UPTAKE AS AFFECTED BY PHOSPHATE SOLUBILIZING AND SULFUR OXIDIZING BACTERIA

Canola (Brassica napus L.) is a very important agricultural and industrial crop. Hence, the effects of chemical and biological treatments on canola oil production and nutrient uptake, under calcareous conditions, were evaluated in a field experiment. Phosphorus (P) fertilizer and sulfur (S)-oxidizing bacteria (Thiobacillus sp.) increased canola oil production by a maximum of 548 and 335 kg ha−1, respectively. P-solubilizing bacteria (Bacillus sp.) and Thiobacillus sp. enhanced the uptake of different nutrients including nitrogen (N), P, potassium (K), zinc (Zn), and manganese (Mn). Monthly measurements of soil P indicated that soil P fluctuations can be managed using the applied treatments for proper P fertilization in canola production. The results indicated the important role of chemical and biological (Bacillus sp.) P sources and S-oxidizing bacteria for canola growth and oil production as they resulted in significant increase in canola oil production and nutrient uptake. This can be very beneficial for the farmers and industry.
High-Pressure Intrinsic Oxidation Kinetics of Two Coal Chars

Chars were produced from two coals (North Dakota lignite and Pittsburgh No. 8 hva bituminous coal) in a flat flame burner at atmospheric pressure. Intrinsic char reactivities to oxygen were then measured in a high-pressure thermogravimetric analyzer as a function of temperature, total pressure, and partial pressure of oxygen. Care was taken to avoid mass transfer effects. Reactivities were normalized by the available mass of char at any given time (g/(g avail .S)). Reactivity data were obtained over a wide range of char burnout and were found to be independent of burnout level between char burnouts of 20 and 60%. Data were obtained at pressures from 1 to 32 atm and at temperatures from 598 to 823 K and were analyzed using the nth order rate law and Arrhenius temperature dependence. The reaction order of each char was shown to be constant at 0.7 for total pressures ranging from 1 to 32 atm and for partial pressures of oxygen ranging from 0.03 to 12.8 atm, and was essentially the same for both chars. Activation energies determined for each char were also determined to be constant with total pressure and partial pressure of 02.
Micellization of two triquaternary ammonium surfactants in aqueous solution

As part of our current studies of oligomeric amphiphiles, two trimeric surfactants containing three dodecyl chains and three quaternary ammonium headgroups connected by 1,3-propanediyl groups, the methyldodecylbis[3-(dimethyldodecylammonio)propyl] ammonium tribromide and trichloride, referred to as 12-3-12-3-12,3Br - and 12-3-12-3-12,3Cl - have been synthesized and purified, and their micellization behavior has been investigated in aqueous solution. On a weight/volume basis, the cmc's of the trimeric surfactants are well below those of the corresonding monomeric and dimeric surfactants (dodecyltrimethylammonium bromide, or DTAB, and 1,3-bis(dodecyldimethylammonio)propane dibromide or 12-3-12,2Br - ), whereas the micelle ionization degrees of the monomeric, dimeric, and trimeric surfactants are rather close. At a given concentration (weight/volume basis), the solution of 12-3-12-3-12,3Br - is much more viscous than that of the corresponding monomeric and dimeric surfactants, indicating a much stronger tendency to micelle growth. Measurements of micelle aggregation numbers at low surfactant concentrations supported this conclusion.
Polylactones, 50: The reactivity of cyclic and noncyclic dibutyltin bisalkoxides as initiators in the polymerization of lactones

Dibutyltin bisethoxide and bis(2,2,2-trifluoroethoxide), the cyclic alkoxides derived from cis-1,4-butenediol, 1,4-butanediol, 1,8-octanediol and triethylene glycol as well as bis(4-nitrophenoxide), bis(4-meth-oxyphenoxide) and tetrabutylstannoxane bisacetae were used as initiators in the polymerization of e-caprolactone (e-CL) and β-BL). Most polymerizations were conducted at 60°C with 2 M solutions in chlorobenzene, and time-conversion curves were recorded. The less reactive initiators yielded sigmoidal time-conversion curves with autoacceleration during the first stage of polymerization. Dibutyltin bisethoxide and the cyclic 1,8-octane dioxide showed the highest reactivities. The less reactive initiators yielded degrees of polymerization (DPs) exceeding the monomer/initiator (M/I) ratios after short reaction times, but a longer reaction times, an equilibration between unreacted initiator and the poly(e-CL) chain took place. The slower polymerizing β-BL yielded DPs paralleling the M/I ratio even with less reactive initiators. The stannoxane and the dibutyltin bisphenoxides were considerably less reactive than the bisalkoxides were considerably less reactive than the bisalkoxides, and only traces of phenylester endgroups were detectable by 1 H NMR spectroscopy. MALDI-TOF mas spectrometry proved the formation of cyclic oligolactones with masses greather than 600 Da for reaction temperatures ≥60°C.
Experimental studies on seed production of tropical grasses in Kenya. 1. General introduction and analysis of problems.

The development of grass seed production in Kenya is described. A discussion is given of the problems in seed growing, of which tjie most pressing are the low yield and quality of the seed. Low yields and quality are due to: — prolonged head emergence within plants; — prolonged flowering within heads; — decreased duration of flowering in late emerged heads; — low seed setting; — low number of head producing tillers ; — extended spread in heading time between plants in a variety; — other factors including low seed retention, spikelet diseases and bird damage. All cultivated varieties show a varying combination of these factors. Some results, together with ways of improvement through agronomic techniques and breeding, are presented and discussed.
Risk Element (As, Cd, Cu, Pb, and Zn) Contamination of Soils and Edible Vegetables in the Vicinity of Guixi Smelter, South China

Risk element (As, Cd, Cu, Pb, and Zn) contamination in soils and in two edible vegetables (Solanum melongena L. and Capsicum annum L.) was investigated in the vicinity of Guixi Smelter, South China. Soil As concentrations averaged 23.9 mg/kg. Sites near the smelter tailings recorded the highest levels of As and heavy metals in soils. The concentration order of heavy metals in soils was Cd < Pb < Zn < Cu. Cu and Cd in soils were abundant in the exchangeable and bound to carbonate fraction, while Pb and Zn were in the residual fraction, limiting their potential toxicity as pollutants. The proportions of the metals in the mobile fraction followed the order Pb < Zn < Cu < Cd. In Solanum melongena L. and Capsicum annum L. , Zn concentration was the highest, followed by Cu, Cd, and Pb, different from that in soils and in the mobile fraction. Concentrations of heavy metals in the labile fractions in soils and in vegetables presented significant correlation (p < 0.05). Both of the two vegetables are not the Cu and Zn accumulators. As for Cd and As, Capsicum annum L. poses a higher risk to animal and human health than Solanum melongena L. , with soil-plant transfer coefficients more than three. Root-stem is the main barrier for most of the heavy metals and As in the two vegetables, resulting in higher metal concentrations in roots relative to other plant tissues. The low stem-fruit transfer coefficients for Zn in Solanum melongena L. and for Pb in Capsicum annum L. suggested that very few of them could reach the fruits.
Simplified embedding schemes for the quantum-chemical description of neutral and charged point defects in SiO2 and related dielectrics

Embedding methods specifically designed to treat large molecules with bulky ligands or in polar solvents are used to describe the electronic structure of point defects in the covalently bonded solids SiO2, Si3N4, and Si2N2O. The mechanical relaxation of the lattice around a given defect, in particular an anion vacancy or interstitial, is described using the ONIOM approach where the system is partitioned in two regions, the local defect treated at the gradient corrected DFT level, and the surrounding matrix treated with a semiempirical Hamiltonian. In this way clusters of 100 atoms and more are used to describe a portion of the solid of 10–15 A of diameter. The long-range lattice polarization induced by a charged defect, a charged oxygen vacancy or a proton bound to O or N atoms, is estimated by means of the isodensity polarized continuum model, IPCM, and compared with the approximate Born’s formula. The two simplified embedding schemes provide a simple way to improve cluster models of neutral and charged .