Miracle-dz/UniFAR-FTUs huggingface dataset:
Orientation relations between four phases of AgI

Starting with wurtzite-type single crystals, AgI was investigated at room temperature and pressures up to 0.5 GPa by means of a polarizing light microscope and with the precession technique. Distinct orientation relations were observed between four different AgI phases that occur suc cessively under increasing pressure. At 0.35 GPa a reverse-obverse (111) twin of zincblende-type AgI is formed with twin plane parallel to the (001) plane of the wurtzite-type structure. The antilitharge type of AgI occurs at 0.39 GPa. Its tetragonal [001] direction runs parallel to one of the (100) directions of the zincblende type. At almost the same pres sure the transformation to the NaCl-type form takes place. This AgI modification shows also twinning on (111) and the basis vectors are oriented parallel to those of the zincblende type. The transition between the zincblende- and the anti litharge-type phase shows a hysteresis: The back transfor mation occurs at 0.35 GPa. NaCl-type AgI transforms di rectly to the zincblende-type form at approximately 0.2 GPa when pressure is released. The observed orientation relations between zincblende-, antilitharge- and NaCl-type AgI support transition mecha nisms that have been proposed earlier [Keen & Hull, J. Phys.: Condens. Matter 5 (1993) 23–32].
HPLC Analysis of Grapevine Phytoalexins Coupling Photodiode Array Detection and Fluorometry

A reversed-phase HPLC method useful for the analysis of the grapevine phytoalexins resveratrol, its β-d-glucoside, e-viniferin, and pterostilbene in leaf extracts was developed by coupling diode array detection and fluorometry. Phytoalexins were extracted from UV-irradiated grapevine leaves with methanol/water (80:20) and prepurified on C18 solid phase extraction cartridges. Separation by HPLC was achieved using a C18 column and a gradient elution with acetonitrile and water (from 10 to 85% acetonitrile). Analyses of grapevine leaf extracts were performed by injecting the equivalent of 1 mg of leaf fresh weight. Recovery was nearly 100% for the three stilbenes resveratrol, pterostilbene, and e-viniferin (ranging from 100.2 to 104.8%), and replicate analyses gave coefficients of variation of 0.6−2.5%. Identification of each phytoalexin was accomplished by line spectral comparisons with known standards, and e-viniferin was further characterized by MS and GC/MS. Simultaneously, stilbenes were detected by flu.
Adsorption-controlled preparation of molecularly imprinted hybrid composites for selective extraction of tetracycline residues from honey and milk

Molecularly imprinted organic–inorganic hybrid composite materials (MIP-HCMs) with controlled swelling and adsorption properties were prepared through copolymerization and the sol–gel process by using doxycycline (DC) as the template molecule, methacrylic acid (MAA) as a functional monomer, methacryloxypropyltrimethoxysilane (KH-570) as a coupling agent and TEOS as an inorganic precursor. By means of changing polymerization conditions as well as the copolymerization ratio of the inorganic precursor and the organic functional monomer, the properties of sorbents can be adjusted for different needs. So the effect of preparation conditions on the structure of the material was studied. The polymer group, thermal stability, adsorption and selectivity characteristics, and the volume swelling degree of the MIP-HCMs were characterized by FTIR, TGA, and dynamic adsorption and swelling experiments, respectively. It was observed that the MIP-HCMs exhibited the highest selectivity (4.9), maximum adsorption capacity (58.2 mg g−1) and good thermal stability. The obtained MIP-HCM was used as an adsorbent for solid-phase extraction of tetracyclines from the milk and honey samples. The average recoveries of three tetracycline antibiotics (DC, tetracycline and chlortetracycline) were obtained in the range of 74.7–115.5% with the precision of 2.1–4.9%. The limits of detection and quantitation of the proposed method were in the range of 4.9–15.3 μg kg−1 and 16.6–51.0 μg kg−1 for the milk samples, and 8.3–15.1 μg kg−1 and 18.3–50.2 μg kg−1 for the honey samples, respectively.
Nonplanar geometries of DNA bases. Ab initio second-order Moeller-Plesset study

Interactions of DNA bases represent a crucial source of DNA conformational variability. Oligonucleotide crystal studies revealed a number of base-base interactions which seem to be stabilized by nonplanar DNA base amino groups. Therefore, an accurate description of the geometry and deformability of the DNA base amino groups is very important. Here, the second-order MOller-Plesset (MP2) 6-31G * -optimized nonplanar geometries of adenine, cytosine, guanine, thymine, and isocytosine are presented. The amino groups of the bases exhibit significant sp 3 pyramidalization. The dihedral angles between the cytosine and adenine rings and their amino group hydrogen atoms range from 10 to 25 o , and the nonplanar cytosine and adenine are 0.4 kcal/mol more stable than the planar molecules
Ag(I) Complexes Containing Flexible N,N‘-Di(2-pyridyl)adipoamide Ligands: Syntheses, Structures, and Ligand Conformations

A new flexible ligand N,N‘-di(2-pyridyl)adipoamide), LCDCl3 (1), and L·2H2O (2), and a series of polymeric complexes of the types [AgLNO3]∞, (3); [AgLPF6]∞, (4); [AgLBF4CH3CN(H2O)0.5]∞, (5); [AgLCl.
Electrochemical Kinetics and X-ray Absorption Spectroscopic Investigations of Oxygen Reduction on Chalcogen-Modified Ruthenium Catalysts in Alkaline Media

The oxygen reduction reaction (ORR) in alkaline media has been investigated on chalcogen-modified ruthenium nanoparticles (Ru/C, Se/Ru/C, Se/RuMo/C, S/Ru/C, S/RuMo/C) synthesized in-house via aqueous routes. In acidic medium, it is well known that modification by a chalcogen prevents the oxidation of the underlying transition-metal (Ru) surface, thereby promoting direct molecular O2 adsorption on the Ru metal. On an unmodified Ru catalyst in alkaline media, the surface oxides on Ru mediate the 2e– reduction of molecular O2 to a stable peroxide anion (HO2–) intermediate via an outer-sphere electron-transfer mechanism. This increases the activity of HO2– near the electrode surface and decreases the overpotential for ORR by effectively carrying out the reduction of HO2– to OH– at the oxide-free ruthenium metal site. An increase in ORR activity of Ru is observed by modification with a chalcogen; however, the increase is not as significant as observed in acidic media. Ternary additives, such as Mo, were found.
Catalytic Hydrocracking of Pyrolytic Lignin to Liquid Fuel in Supercritical Ethanol

Pyrolytic lignins (PLs) are the major components in fast pyrolysis bio-oils and have detrimental effects on bio-oil properties. The existence of PLs also makes bio-oil upgrading rather difficult due to their nonvolatility and thermal instability. In this study, PL produced from rice husk was hydrocracked at 260 °C in supercritical ethanol under a hydrogen atmosphere by the use of Ru/ZrO2/SBA-15 or Ru/SO42−/ZrO2/SBA-15 catalyst. Trace amount of tar or coke was produced after the hydrocracking process, and most of the PL was converted into liquid fuel consisting of stable organic compounds with a heating value as high as 34.94 MJ/kg. The liquid product distribution was investigated by gas chromatography/mass spectrometry (GC-MS). The results demonstrated that, under supercritical ethanol conditions, Ru/ZrO2/SBA-15 and Ru/SO42−/ZrO2/SBA-15 were effective catalysts to convert PL to stable organic compounds such as phenols, guaiacols, anisoles, esters, light ketones, alcohols, long-chain alkanes, etc.
Corrigendum to "Thermodynamics of reactions of ClHg and BrHg radicals with atmospherically abundant free radicals" published in Atmos. Chem. Phys. 12, 10271–10279, 2012

3. We mischaracterized the compounds described by Balabanov and Peterson (2003, cited as 2003b in the original paper). Balabanov and Peterson (2003) listed compounds as HgBrO and HgClO, following a convention of stoichiometric formulae in which atoms are listed from least to most electronegative. We misread these stoichiometricformulae asstructuralformulae for HgBrO and HgClO (a mercury atom bound to the halogen atom of a BrO or ClO radical). In fact, Balabanov and Peterson (2003) were describing divalent Hg(II) compounds with structural formulae BrHgO and ClHgO (a mercury atom bound directly to both an oxygen atom and a halogen atom). Note these same divalent Hg(II) compounds are described by stoichiometric formulae in another paper by Balabanov and Peterson (2004). In fact, no previous paper describes molecules with the structural formula HgBrO or HgClO.
Production of geranyl propionate by enzymatic esterification of geraniol and propionic acid in solvent‐free system

Background: This work reports the optimization of geranyl propionate production by esterification of geraniol and propionic acid in a solvent-free system using a commercial lipase as catalyst. For this purpose, a sequential strategy was performed applying two experimental designs. Results: The operating conditions that optimized geranyl propionate production were determined to be 40 °C, geraniol to propionic acid molar ratio of 3:1, 150 rpm and 10 wt% of enzyme, with a resulting reaction conversion of about 93%. After determining the optimum reaction parameters, a kinetic study was carried out evaluating the influence of substrates molar ratio, enzyme concentration and temperature on reaction conversion. Results obtained in this step allow one to conclude that an excess of alcohol (acid to alcohol molar ratio of 1:6), relatively low enzyme concentration (5 wt%), temperature of 40 °C and substrates molar ratio of 1:1 afforded nearly complete reaction conversion after 30 min of reaction. Conclusion: New experimental data on enzymatic esterification of geraniol and propionic acid for geranyl propionate production are reported in this work, showing a promising perspective of the technique to overcome the well-known drawbacks of the chemical-catalyzed route. Copyright © 2010 Society of Chemical Industry
Separation of BTEX aromatics from n-octane using a (tetrabutylammonium bromide + sulfolane) deep eutectic solvent – experiments and COSMO-RS prediction

Separation of aromatics from aliphatics is a challenging process because of the close range of their boiling points and the formation of several combinations of azeotropes. Until now, no feasible separation process is available for aromatic concentrations below 20 wt%. In this work, we have investigated the possibility of using a selected deep eutectic solvent (DES) for the liquid–liquid extraction of benzene, toluene, ethylbenzene and m-xylene (BTEX) aromatics. The DES used in this work was synthesized by combining tetrabutylammonium salt and sulfolane. Equilibrium data for the ternary system consisting of BTEX aromatics, n-octane and DES were measured at 25 °C and atmospheric pressure. The results showed that the used DESs have comparable distribution ratios and selectivities to those of commercial solvents. In all tested systems, sulfolane was not present in the hydrocarbon layer. It was also found that the selectivity decreases with decreasing polarity of the aromatic compound. The Non-Random Two Liquid (NRTL) model was successfully used to correlate the experimental tie-lines and to calculate the phase compositions of the ternary systems. In addition, the performance of COSMO-RS to predict the ternary tie-lines for the studied systems was evaluated and the σ-profiles were used to explain the interaction between the DES and the aromatic compounds.
DFT study of hydrogen adsorption on Al13 clusters

In this work, adsorption of hydrogen on Al13 clusters has been investigated theoretically using the density functional theory (DFT) approach. We have performed geometry optimization of atomic and molecular hydrogen in the proximity of Al13 and calculated the binding energy and electronic properties of the stable Al13+Hn assemblies. We have also calculated the energy barrier for the hydrogen atom transition between different adsorption sites on Al13 cluster as well as the activation energy for the dissociation and adsorption of molecular hydrogen. We found that the hydrogen atom adsorbs on the surface of Al13 cluster, without an energy barrier onto atop, bridge and hollow sites. A small barrier for H atom transition from one adsorption site to another together with the minor energy difference between the most stable isomers points towards high mobility of the hydrogen atom on the surface. The calculated dissociation–adsorption barrier for the hydrogen molecule of ∼14 kcal/mol and a desorption barrier of ∼19 kcal/mol together with a high theoretical storage capacity of Al13 clusters suggest further investigations of Al nanostructures for application in hydrogen storage.
Synthesis of Nanosized TiO2-Ag-SiO2 Sols by Modified Sol-Gel Method and their Application for Methane Hydrate Formation

Nanosized TiO2-Ag-SiO2 sols were prepared with modified sol-gel method using reduction agent. The physical properties of the prepared particles were investigated by TEM, XRD and FT-IR. The titanium tetraisopropoxide (TTIP, 98% Aldrich), teraethylorthosilicate (TEOS, 98% Aldrich) and silver nitrate were used as precursors of titania, silica and silver, respectively. Sodium citrate tribasic dihydrate (C6H5Na3.2H2O, Aldrich) was used as a reduction agent. This paper presents the effect of nanosized TiO2-Ag-SiO2 sols on the formation of methane hydrate in a semi-batch vessel. The micrographs of TEM showed that the TiO2-Ag-SiO2 particles possessed a spherical morphology with a narrow size distribution. The crystallite size of particles decreased with an increasing the SiO2 content. In addition, the water solution with 1.0 wt% of TiO2-Ag-SiO2 particles acted as promoter for methane hydrate formation.
Characterization of Polymetal Gate Transistors With Low-Temperature Atomic-Layer-Deposition-Grown Oxide Spacer

In this letter, W/WNx/poly-Si gate DRAM transistors with oxide spacers grown by low-temperature atomic layer deposition (ALD) have been fabricated, and the electrical characteristics are analyzed. The low-temperature ALD oxide effectively prevents the oxidation of exposed tungsten, and the fabricated devices show superior electrical properties to those with nitride/oxide spacer. The data retention time is improved by 30%, and the hot-carrier degradation characteristics are also enhanced. The threshold voltage of the fabricated W/WNx/poly-Si gate n-channel transistors with ALD oxide spacer is increased due to the suppression of boron deactivation by hydrogen. In particular, the transconductance of n-channel transistors in core/peripheral circuits was found to be enhanced by less-compressive stress in ALD oxide spacers.
Revised phase diagram and X‐ray data of The Mn3O4 ? Al2O3 System in air

The phase diagram of the quasi-binary Mn3O4Al2O3 system in air has been redetermined at temperatures from 850 to 1550°C with the help of the X-ray powder diffraction technique including high-temperature diffractometry. Lattice constants of manganese aluminates and the powder diffraction patterns of Mn3O4, MnAl2O4 and Mn2AlO4 are presented. The influence of specimen cooling on the cubic-to-tetragonal transition of MnAl spinels is demonstrated. The inversion degree of the spinal compounds is discussed. Revision des Phasendiagramms und der Rontgendaten des Systems Mn3O4Al2O3 in Luftatmosphare. Mit Hilfe der Pulvermethode, einschlieslich Hochtemperaturrontgenaufnahmen, ist des Phasendiagramm des quasi-binaren Systems Mn3O4Al2O3 in Luft und bei 850–15500C von neuem untersucht worden. Die Gitterparameter der Manganaluminate und die Rontgenbeugungsdiagramme von Mn2O4, MnAl2O4 und Mn2AlO4 werden angegeben. Der Einflus des Abkuhlens auf den Ubergang von kubischen zu tetragonalen Manganaluminatspinellen wird dargestellt. Der Inversionsgrad der Spinelle wird besprochen.
Toward a standardised thermal-optical protocol for measuring atmospheric organic and elemental carbon: the EUSAAR protocol

Abstract. Thermal-optical analysis is a conventional method for determining the carbonaceous aerosol fraction and for classifying it into organic carbon, OC, and elemental carbon, EC. Unfortunately, the different thermal evolution protocols in use can result in a wide elemental carbon-to-total carbon variation by up to a factor of five. In Europe, there is currently no standard procedure for determining the carbonaceous aerosol fraction which implies that data from different laboratories at various sites are of unknown accuracy and cannot be considered comparable. In the framework of the EU-project EUSAAR (European Supersites for Atmospheric Aerosol Research), a comprehensive study has been carried out to identify the causes of differences in the EC measured using different thermal evolution protocols; thereby the major positive and negative biases affecting thermal-optical analysis have been isolated and minimised to define an optimised protocol suitable for European aerosols. Our approach to improve the accuracy of the discrimination between OC and EC was essentially based on four goals. Firstly, charring corrections rely on faulty assumptions – e.g. pyrolytic carbon is considered to evolve completely before native EC throughout the analysis –, thus we have reduced pyrolysis to a minimum by favoring volatilisation of OC. Secondly, we have minimised the potential negative bias in EC determination due to early evolution of light absorbing carbon species at higher temperatures in the He-mode, including both native EC and combinations of native EC and pyrolytic carbon potentially with different specific attenuation cross section values. Thirdly, we have minimised the potential positive bias in EC determination resulting from the incomplete evolution of OC during the He-mode which then evolves during the He/O2-mode, potentially after the split point. Finally, we have minimised the uncertainty due to the position of the OC/EC split point on the FID response profile by introducing multiple desorption steps in the He/O2-mode. Based on different types of carbonaceous PM encountered across Europe, we have defined an optimised thermal evolution protocol, the EUSAAR_2 protocol, as follows: step 1 in He, 200 °C for 120 s; step 2 in He 300 °C for 150 s; step 3 in He 450 °C for 180 s; step 4 in He 650 °C for 180 s. For steps 1–4 in He/O2, the conditions are 500 °C for 120 s, 550 °C for 120 s, 700 ° C for 70 s, and 850 °C for 80 s, respectively.
Comparison of Conventional and Polymer Coated Urea as Nitrogen Sources for Lowland Rice Production

Nitrogen (N) is one of the most yield limiting nutrients in lowland rice production. Improving N use efficiency is essential to reduce cost of crop production and environmental pollution. A greenhouse experiment was conducted with the objective to compare conventional and polymer coated urea for lowland rice production. Grain yield, straw yield, panicle density, maximum root length, and root dry weight were significantly increased in a quadratic fashion with the increase of N rate from 0 to 400 mg kg−1 soil. Nitrogen source X N rate interactions for most of these traits were not significant, indicating that lowland rice responded similarly to change in N rates of two N sources. Based on regression equations, maximum grain yield was obtained with the application of 258 mg N kg−1 soil and maximum straw yield was obtained with the addition of 309 mg N kg−1 soil. Nitrogen use efficiency (grain yield per unit of N applied) was maximum for polymer coated urea compared to conventional urea. Root length and root dry weight improved at an adequate N rate, indicating importance of N fertilization in the absorption of water and nutrients and consequently yield. Polymer coated urea had higher soil exchangeable calcium (Ca) and magnesium (Mg), Ca saturation, Mg saturation, base saturation, and effective cation exchange capacity compared to conventional urea. There was a highly significant decrease in soil exchangeable potassium (K) with increasing N rates at harvest of rice plants.
Characterization and performance of dodecyl amine functionalized graphene oxide and dodecyl amine functionalized graphene/high-density polyethylene nanocomposites: A comparative study

Dodecyl amine (DA) functionalized graphene oxide(DA-GO) and dodecyl amine functionalized reduced graphene oxide (DA-RGO) were produced by using amidation reaction and chemical reduction, then two kinds of well dispersed DA-GO/high-density polyethylene (HDPE) and DA-RGO/HDPE nanocomposites were prepared by solution mixing method and hot-pressing process. Thermogravimetric, X-ray photoelectron spectroscopy, Fourier transforms infrared spectroscopy, X-ray diffractions, and Raman spectroscopy analyses showed that DA was successfully grafted onto the graphene oxide surface by uncleophilic substitution and the amidation reaction, which increased the intragallery spacing of graphite oxide, resulting in the uniform dispersion of DA-GO and DA-RGO in the nonpolar xylene solvent. Morphological analysis of nanocomposites showed that both DA-GO and DA-RGO were homogeneously dispersed in HDPE matrix and formed strong interfacial interaction. Although the crystallinity, dynamic mechanical, gas barrier, and thermal stability properties of HDPE were significantly improved by addition of small amount of DA-GO or DA-RGO, the performance comparison of DA-GO/HDPE and DA-RGO/HDPE nanocomposites indicated that the reduction of DA-GO was not necessary because the interfacial adhesion and aspect ratio of graphene sheets had hardly changed after reduction, which resulting in almost the same properties between DA-GO/HDPE and DA-RGO/HDPE nanocomposites. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39803.
Aerosol number–size distributions during clear and fog periods in the summer high Arctic: 1991, 1996 and 2001

The present study covers submicrometer aerosol size distribution data taken during three Arctic icebreaker expeditions in the summers of 1991, 1996 and 2001. The size distributions of all expeditions were compared in log-normally fitted form to the statistics of the marine number size distribution provided by Heintzenberg et al. (2004) yielding rather similar log-normal parameters of the modes. Statistics of the modal concentrations revealed strong concentration decreases of large accumulation mode particles with increasing length of time spent over the pack ice. The travel-time dependencies of both Aitken and ultrafine modes strongly indicate, as other studies did before, the occurrence of fine-particle sources in the inner Arctic. With two approaches evidence of fog-related aerosol source processeswas sought for in the data sets of 1996 and 2001 because they included fog drop size distributions. With increasing fog intensity modes in interstitial particle number concentrations appeared in particular in the size range around 80 nm that was nearly mode free in clear air. A second, dynamic approach revealed that Aitken mode concentrations increased strongly above their respective fog-period medians in both years before maximum drop numbers were reached in both years. We interpret the results of both approaches as strong indications of fog-related aerosol source processes as discussed in Leck and Bigg (1999) that need to be elucidated with further data from dedicated fog experiments in future Arctic expeditions in order to understand the life cycle of the aerosol over the high Arctic pack ice area.
Improved method of analysis for ergovaline in tall fescue by high-performance liquid chromatography

A rapid HPLC method of analysis for ergovaline in tall fescue plants is presented; it offers the advantages of utilizing readily available materials that are safer to use than those in previous methods. In addition, the sample preparation and chromatographic method allow for the detection and quantification of both C-8 epimers of the target alkaloid. Inclusion of the epimer in the analysis procedure provides a more accurate method of determining total ergovaline in plant materials. Keywords: Festuca arundinacea; Neotyphodium coenophialum; Acremonium coenophialum