Miracle-dz/UniFAR-FTUs huggingface dataset:
Structural Regulation and Optical Properties of One-Dimensional ZnO Nanomaterials in Situ Grown from and on Brass Substrates

One-dimensional ZnO nanostructures have been in situ grown on the conductive brass substrate by directly heating the Cu0.70Zn0. 30 alloy foils in O2/Ar at 550−900 °C. The growth process and products have been well characterized by means of X-ray diffraction, Raman scattering, electron microscopy, X-ray photoelectron, and photoluminescence spectroscopy. The results indicate that more Zn species is lost from the brass foils at the higher temperatures. Zn species is exhausted, and a sharp diffraction peak shift appears around 750 °C due to the quick depletion. The structures of the ZnO products have been systematically regulated and the more oxygen vacancy is associated with the higher reaction temperature. The correlation in between the oxygen vacancy concentration and the green and exciton emission for these products has been experimentally demonstrated and well understood, which is important for luminescence applications.
Segment connectivity, chain-length breathing, segmental stretch, and constraint release in reptation models. II. Double-step strain predictions

Predictions for double-step strain flows are presented using a newly proposed reptation theory that accounts for segment connectivity, chain-length breathing, segmental stretch and constraint release in a self-consistent, full-chain theory. In this part of the work emphasis is on double-step shear strains where the second step is reversed and the imposition time of the second strain is earlier than the estimated retraction time, for which the Doi–Edwards model and single-integral models have been found to be incapable of describing experimental trends. Transient stress relaxation properties of two types of reversing flows, types B and C, have been examined and compared to the predictions obtained from the Doi–Edwards model and a single-integral model. The simulations show excellent agreement with the experimental trends based on recent mechanical and optical measurements.
Contribution of Deep Eutectic Solvents for Biomass Processing: Opportunities, Challenges, and Limitations

Since their introduction in 2004, deep eutectic solvents (DESs) have attracted interest in different fields of chemistry. In the case of biomass, DESs are particularly interesting, not only because of their low cost and biodegradability, but also due to their unique property to interact with hydrogen‐bond donors such as renewably sourced polyols or carboxylic acids. Through selected examples, we report the contribution of DESs for the dissolution of biomass, the extraction/purification of bioderived chemicals, and the conversion of carbohydrates to furanic derivatives. In all examples, we discuss how the DES can impact the selectivity of a chemical process and the limitations associated with the use of DES. In particular, impact of the DES viscosity on extraction, the recovery and recycling of DES, and the stabilization of chemical intermediates in DES are among the key aspects that are discussed.
Photophysical studies on a fluorescence probe labelled fatty acid: chain folding in a micellar environment

The photophysical properties of a 4-aminophthalimide fluorophore labelled detergent, 11-(4-aminophthalimido)undecanoic acid, that is capable of acting as a probe for microheterogeneous media, has been studied in homogeneous and micellar environments. From the surfactant-induced changes in fluorescence intensities, the binding constants and the critical micellar concentrations of three different micelles have been determined. The location of the fluorophore in the micellar environment is determined on the basis of the spectral shift, changes in fluorescence intensity and lifetime in micellar media and fluorescence quenching behaviour towards selected ionic quenchers. It is shown that despite its covalent linking with the non-polar tail of the surfactant chain, the fluorescing moiety localises itself in the interfacial region of the micelle by folding up of the long alkane chain.
Simultaneously measuring ocular aberration and anterior segment biometry during accommodation

In the human eye, accommodation is essential for functional vision. However, the mechanisms regulating accommodation and the ocular parameters affecting aberrations remain to be explored. In order to measure the alterations of ocular aberration and crystalline lens biometry during dynamic accommodative stimuli, we designed an optical coherence tomography with ultra-long penetration depth (UL-OCT) combined with a Shack–Hartmann wavefront sensor (SHWFS). This integrated set up measures human eye's anterior segment as well as monochromatic high-order aberrations (HOAs) with 6 μm resolution and (1/20) λ accuracy. A total of 10 healthy volunteers without ocular diseases were examined. Upon exposure to accommodative stimuli, the wavefront aberrations became larger. Among the anterior segment biometry, the anterior crystalline lens demonstrated significant curvature during accommodation and was the major cause of high-order aberration. These findings suggest that the front surface of the crystalline lens can significantly affect variation among aberrations, which is a key factor underlying the quality of human vision.
Synthesis, Crystal Structure, and Luminescent Properties of a New In(III) Compound Based on 5-Oxyacetateisophthalic Acid

A new In(III) coordination polymer, namely [In(OABDC)(H2O)]n (1 H3OABDC = 5-oxyacetateisophthalic acid), has been successfully synthesized and structurally characterized. Single-crystal X-ray analysis reveals that 1 is a two-dimensional (2D) framework based on dinuclear [In2(COO)2] subunits, and can be simplified into a (3,6)-connected kgd network. Moreover, this compound shows intense luminescence emission at room temperature.
Mitigation of CO2 by Chemical Conversion: Plausible Chemical Reactions and Promising Products

A critical literature analysis was conducted on the viable usage of CO2 in the framework of the attempts to reduce the emissions of CO2 into the atmosphere from various processes or the rate of increase of the concentration of CO2 in the atmosphere. Applications based on the physical properties of CO2 are summarized first. Major examples are applications in supercritical extraction, enhanced oil recovery, and use as inert gas in fire extinguishing and safety application in industry. The various possibilities of use in chemical applications are systematically discussed. CO2 can react with several hydrocarbons and nitrogen-containing compounds (NH3, amines, imines). It can be used as a weak acid or as an oxidizing agent. It can be reduced electrochemically, photochemically, or chemically or by a syngas route. A variety of products can be manufactured from CO2, e.g., acids, alcohols, esters, lactones, carbamates, urethanes, urea derivatives, various copolymers, and polymers. In particular, polycarbonates are.
Impact of Distortion of Porphyrins on Axial Coordination in (Porphyrinato)zinc(II) Complexes with Aminopyridines as Axial Ligands

A series of (porphyrinato)zinc(II) compounds were synthesized with use of 5,10,15,20-tetraphenylporphyrin (H2TPP), 2,3,5,10,12,13,15,20-octaphenylporphyrin (H2OPP), and 2,3,5,7,8,10,12,13,15,17,18,20-dodecaphenylporphyrin (H2DPP). Those compounds form complexes with aniline, pyridine, and 3- and 4-aminopyridines as axial ligands. X-ray crystallography was performed on the complexes with 3-aminopyridine (3-AP) and 4-aminopyridine (4-AP) as axial ligands. 3-Aminopyridine was revealed to bind through the amino group to the Zn(OPP), exhibiting intermolecular π–π interaction between 3-AP and one of the pyrrole rings and intermolecular NH–π interactions of the coordinated amino group with two β-phenyl groups of an adjacent molecule. In solution, the aminopyridines form a single species at ambient temperature and are assumed to have pyridine coordination through the aromatic pyridine nitrogen atom. Variable-temperature NMR spectroscopy in CD2Cl2 indicates that two different species exist at lower temperatures, suggesting that amino-bound complexes of 3-AP can be formed as a metastable species in solution, which is stabilized in the crystal as a result of noncovalent interactions. The binding constants of aminopyridines to the three kinds of (porphyrinato)zinc complexes reveal enhancement of the axial ligation by virtue of the distortion of the porphyrin ring. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Correlation of 13C-NMR analysis with fungal decay tests of polymeric structural wood constituents. II. Ground contact tests

Heat treatment at relatively high tempera- tures (ranging from 150°C to 260°C) appear to be an effective method to improve the durability of wood. This study in- vestigated the reasons for the decay resistance of heat- treated and untreated wood as composed of polymeric structural constituents by solid-state CP-MAS 13 C-NMR analysis after fungal exposure in ground contact. An indus- trially used two-stage heat treatment method under rela- tively mild conditions (200°C) was used to treat the sam- ples. Fungal exposure in ground contact resulted in strong degradation of the carbohydrates (cellulose and hemicellu- lose) of treated and untreated Scots pine, Radiata pine, and Simaruba. Fungal attack of the carbohydrates appeared to occur mainly at C4, resulting in cleavage and eventually depolymerization of cellulose and hemicellulose. The CP- MAS 13 C-NMR spectra of the heat-treated wood revealed similarities but also clear differences after fungal exposure in ground contact with the untreated wood. In ground contact fungi appeared to attack the carbohydrates of heat-treated wood at C1 and possibly at C4 in order to cleave and eventually depolymerize cellulose and hemicellulose. An attack on the out-of-the-ring alcoholic group, OCH2OH, of the carbohydrates of the heat-treated wood was observed (particularly in treated Radiata pine). The fungus possibly tried to cleave the out-of-the-ring CH2OOH group on the main H-bond fixing sites of the crystalline cellulose structure in order to open the cellulose crystalline structure to an amorphous structure to decrease its water repellency and facilitate enzymatic cellulose degradation; this was also ob- served, but to a lesser extent, in untreated Radiata pine and untreated Scots pine. The opening of the glucose pyranose ring in heat-treated Simaruba after fungal exposure, not observed in the untreated wood, was remarkable, and the thermal degradation of alpha-arabinofuranose during heat treatment indicated more extensive decay. Demethoxylation and ring opening of the aromatic structure of lignin were observed, especially in the heat-treated Radiata pine, Doug- las fir, and Simaruba. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 616 - 622, 2006
Ultrafast x-ray pulse generation by focusing femtosecond infrared laser pulses onto aqueous solutions of alkali metal chloride

X-ray pulses were generated by focusing femtosecond infrared laser pulses (775 nm, 130 fs, 0.58 mJ/pulse) onto an alkali metal (Cs or Rb) chloride aqueous solution jet. The mechanism of x-ray pulse generation was studied by measuring x-ray emission spectra and transmitted laser pulse spectra. Addition of CsCl to distilled water was found to enhance markedly x-ray intensity and x-ray cutoff energy. The frequency-up-shift observed in transmitted laser pulses was larger in CsCl solution than in distilled water. The results suggested that a high-density plasma-like medium was produced in CsCl solution due to secondary electrons.
Synthesis and structural characterizations of [chromophore]+‐saponite/polyurethane nanocomposites

In this study, three chromophores—p-nitroaniline, 4-(4-nitrophenylazo)aniline, and 4-[(E)-2-{4-[(E)-2-(4-nitrophenyl)-1-diazenyl]phenyl}-1-diazenyl]aniline—were intercalated into layered aluminosilicate saponite and then dispersed into the polyurethanes matrix. The intercalated chromophore/saponite complexes were examined by inductively coupled plasma emission and element analysis technologies. The molecular orbital package computation simulation and X-ray diffraction (XRD) analysis showed that possible configurations of chromophore ions on the gallery surfaces of saponite suggest that the chromophore molecules lie parallel to the basal planes of silicate as an inclined paraffin structure or as pseudo-multilayers. The XRD and transmission electron microscopy analysis indicated that the delamination of organoclay in the polyurethanes matrix exhibited nanolayers, exfoliated structure, or both. In particular, even at high doping levels up to 15 wt % of organoclay, the [chromophore]+-saponite/polyurethanes film did not display a macroscopic aggregation of layered silicates and showed high transparency. The thermal stability of chromophore was significantly enhanced as intercalated into the layered aluminosilicate saponite, and the glass-transition temperature of [chromophore]+-saponite/polyurethanes nanocomposites proportionally increased with increased clay content. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 1690–1703, 2002
Optical Resolution of 1-(3-Methoxyphenyl)ethylamine with Enantiomerically Pure Mandelic Acid, and the Crystal Structure of Less-Soluble Diastereomeric Salt

Enantiomerically pure 1-(3-methoxyphenyl)ethylamine (1), which is a key intermediate of new phenyl carbamate drugs, was obtained by a diastereomeric method with high resolution efficiency (E) by using enantiomerically pure mandelic acid (2) as a resolving agent. The first crystallization of the mixture of diastereomeric salts from methanol gave a less-soluble diastereomeric salt in 70% yield with 99% diastereomeric excess. Recrystallization of the salt from 2-propanol gave (R)-1·(R)-2 in 97% yield with 100% diastereomeric excess (total E = 68%). The crystal structure of the less-soluble diastereomeric salt, (R)-1·(R)-2, was determined by X-ray crystallography. The crystal data are: Monoclinic, space group P21, a = 12.642(4), b = 5.890(2), c = 10.855(4) A, β = 103.68(3)°, V = 785.4(5) A3, Z = 2, R = 0.058 for 1450 unique reflections. The X-ray crystallography revealed that the high resolution efficiency was due to a layer-like arrangement of the enantiomerically pure acids, of which two layers sandwiched a.
A simple preconcentration-storing technique based on sulfide precipitation for multipoint monitoring of mercury in rainwater and snow by cold vapor atomic absorption spectrometry

A preconcentration-storing technique that does not require any special or expensive apparatus and reagents was developed to monitor mercury in rainwater and snow at many points as simultaneously as possible. A commercially available sodium hypochlorite solution was added to the sample solution to prevent a decrease in mercury concentration after sampling. Mercury(II) ion (0.5-50 ng) in 500 mL of the sample solution was concentrated by adding zinc(II) ion and a small amount of sulfide ion and then coagulating/coprecipitating with Zn(OH) 2 or ZnS after reduction of residual hypochlorite by addition of hydroxylammonium chloride. The supernatant solution was discarded by decantation, and the solution including the precipitates could be stored for at least 20 days without any loss of mercury. The recoveries of mercury(II) ion from the 500 mL of the sample solutions spiked with mercury(II) ions were 99-109%, with standard deviation ranges of 3-8%, although the recovery of methylmercury(II) ion was 68 ± 5%. Using this technique, the determination of mercury in rainwater and snow was demonstrated at Toyama Prefecture, Japan, from April 2004 to February 2005; mercury levels ranging from 2.7 to 33.7 ng L -1 were found.
An acoustical method for determining the thermal and momentum accommodation of gases on solids

The velocity and absorption of sound in He, Ne, and Ar have been measured at room temperature and pressures ranging from 6.0−0.3 torr. The gases were contained in a tungsten tube 0.953 cm i.d. Flashing this tube at approximately 1900°C in a high vacuum before the measurements produced a marked increase in the sound velocity and a marked decrease in the sound absorption. The effect has been attributed to a decrease in the thermal and momentum accommodation coefficients produced by removing the adsorbed gases from the tungsten surface. In the presence of mischmetal getter, the accommodation coefficients for the surface after flashing remained constant for a period of two weeks. When oxygen was admitted to the system momentarily to a pressure of a few torr and then pumped out, the sound velocity and absorption in the noble gases returned to values corresponding to higher accommodation coefficients. The effect was repeatable. Comparison of the measured absorption and velocity with theoretical curves places re.
Simulation of Interaction of Coal Associates with Solvents Using the Molecular Dynamics Calculation

The extract obtained from a carbon disulfide−N-methyl-2-pyrrolidinone mixed-solvent extraction at room temperature for Upper Freeport coal (APCS1) was fractionated with acetone and pyridine into three fractions, i.e., acetone-soluble (AS), acetone-insoluble−pyridine-soluble (PS), and pyridine-insoluble (PI) fractions. For the three extract fractions, the model structures based on the structural parameters were constructed, and the energy-minimum conformation was calculated by the molecular mechanics and molecular dynamics methods. As the fractions got heavier, more stable associates formed among the model structures by several cooperative interactions through aromatic−aromatic interactions, hydrogen bonds, and electrostatic interactions. Furthermore, the molecular dynamics calculation in the presence of pyridine showed that a part of the coal associates was broken by their interactions with pyridine molecules. When benzene or methanol was used as the solvent, the breaking of coal associates did not take p.
Influence Prediction of Alkylamines Upon Electrical Percolation of AOT-based Microemulsions Using Artificial Neural Networks

Abstract Simulations for the electrical percolation of AOT/iC8/H2O w/o microemulsions added with alkylamines have been carried out by means of multilayer perceptron. Five variables have been elected as inputs: amine concentration, molecular weight, log P, hydrocarbon chain length (as number of carbons), and pKa. As a result, a neural model consisting in five input neurons, two middle layers (with fifteen and ten neurons respectively) and one output neuron was chosen because of its better performance, with a RMSE of 0.54 °C for the prediction set, with R2 = 0.9976.
Surface plasmon waveguide Schottky detectors operating near breakdown

Surface plasmon waveguide Schottky detectors were investigated experimentally at room temperature near junction breakdown. The detectors consist of an Au stripe on n‐Si forming a Schottky contact thereon and supporting strongly confined surface plasmons localised at the Au/Si interface. The detectors were excited by end‐fire coupling at λ0 = 1310 nm where the detection mechanism is the internal photoelectric effect. A ∼10× increase in responsivity was measured at strong reverse biases compared to no bias due to plasmon‐induced junction breakdown. A maximum responsivity of 2.35 mA/W is reported.
Spectroscopic and quantum-control aspects of ultrashort-pulse synthesis through impulsive high-order stimulated Raman scattering

The spectroscopic and quantum-control aspects of short-pulse synthesis through the generation of multiple Stokes and anti-Stokes sidebands in an impulsively pre-excited Raman-active medium are considered. The use of sequences of short laser pulses leading to a resonant excitation of Raman modes is shown to allow the generation of multiple Stokes and anti-Stokes sidebands to be considerably enhanced, with the characteristic length of the spectral broadening of a probe pulse propagating in a Raman-active medium pre-excited by a sequence of short pulses being inversely proportional to the number of pulses in this sequence. Coherent four-wave mixing techniques are shown to be a convenient tool for visualizing the result of impulsive preparation of a Raman-active medium. The results of Raman spectroscopic studies are used to specify Raman-active molecules with sufficiently short periods of Raman vibrations and high efficiencies of Raman scattering, which offer especially much promise for the generation of few-cycle light pulses in Raman-active media. Copyright © 2002 John Wiley & Sons, Ltd.
Synthesis and Properties of a Novel Bismaleimide Resin Containing 1,3,4-Oxadiazole Moiety and the Blend Systems Thereof With Epoxy Resin

A new bismaleimide monomer, 2-((4-maleimidophenoxy)methyl)-5-(4-maleimidophenyl)-1,3,4-oxadiazole (Mioxd), was designed and synthesized. The chemical structure of the monomer was confirmed by means of Fourier transform infrared (FTIR) spectroscopy, proton nuclear magnetic resonance (1H NMR) spectroscopy and elemental analysis, and its thermal properties were characterized using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Mioxd as a reactive modifier was blended with epoxy resin based on bisphenol A diglycidyl ether (DGEBA) in weight ratio of 5, 10, and 15%, using 4,4′-diaminodiphenyl sulfone (DDS) as hardener. The effect of Mioxd addition on the cure behavior and thermal properties of the blend resins was studied by DSC, TGA, and dynamic mechanical analysis (DMA). DSC investigations showed that the main exothermic peak temperature (Tp) of the blend systems did not obviously shift with increasing Mioxd content whereas a new shoulder appeared and gradually grew on the high temperature side of the exothermic peak. The results of DMA measurements exhibited the glassy storage modulus (G') and glass transition temperatures (Tg) increased as the Mioxd content was increased, the cured blends investigated were miscible and no phase separation occurred. Further, the thermal decomposition temperature first decreased and then increased, but the char yield at 600°C increased with an increase in Mioxd content. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
The complex chemistry of N-(phosphonomethyl)glycine (glyphosate): preparation and characterization of the ammonium, lithium, sodium (4 polymorphs) and silver(I) complexes

A series of complexes with the herbicide glyphosate [N-(phosphonomethyl)glycine = H3L] has been synthesized and characterized using infrared spectroscopy, and in the case of five of these, by single crystal X-ray diffraction. The compounds are ammonium glyphosate [NH4][H2L] 1, lithium glyphosate Li(H2L) 2, sodium glyphosate hemi-hydrate Na(H2L)·0.5H2O 3, sodium glyphosate monohydrate Na(H2L)·H2O 4, sodium glyphosate dihydrate Na(H2L)·2H2O 5, disodium glyphosate nonahydrate Na2(HL)·9H2O 6 and disilver glyphosate Ag2(HL) 7. The crystal structures of 1, 3, 4, 6 and 7 have been determined. Compound 1 consists of a hydrogen-bonded lattice structure in which all of the available ammonium protons are involved in hydrogen bonding, together with the zwitterionic amine group and the single phosphonate proton. Compounds 3 and 4 are both polymeric and based on dimeric repeating units with six-co-ordinate sodium centres. Complex 6 is based on both discrete octahedral [Na(HL)(H2O)5]− anionic complex units with the unidentate glyphosate ligand bonded via a carboxylate oxygen, together with a cationic [Na2(H2O)8]2+ ribbon polymer. All structures have extensive hydrogen bonding interactions. The silver complex 7 is a polymer structure which involves the phosphonate ligands in linear chains joined through the carboxyl group at one end (via bis-O,O′ bridged silver dimers) and silver co-ordinated phosphonate oxygens at the other.