Miracle-dz/UniFAR-FTUs huggingface dataset:
Comparison of Metal Uptake Properties of Silica Gel-Bound Ion Exchangers and Some Amine Derivatives

Silica gel bound to some amine derivatives such as semicarbazide, thiosemicarbazide, ethylenediamine and phenylenediamine as well as ion exchangers containing carboxylic groups derived from phthalic anhydride and succinic anhydride were synthesized, and their metal-uptake properties in aqueous solution were studied. The factors controlling and influencing the metal uptake capacity, such as shaking time and pH of the metal ion solution, were also determined to evaluate and compare the performance toward metal ion extraction. The data in this study show that the values of metal capacity of the silica gel-bound complexing agents are higher than those of the ion exchanger analogs, and those of the immobilized aliphatic diamines or acid derivatives are higher than the corresponding values of aromatic analogs. A method of recycling the synthesized phases after metal extraction processes, for the sake of further and successive use of the recycled phases, is also presented.
Microscopic density functional theory of wetting and drying of a solid substrate by an explicit solvent model of ionic solutions

Classical density functional theory (DFT) of inhomogeneous fluids is applied to an explicit solvent ‘semi-primitive’ model (SPM) of ionic solutions to investigate the influence of ionic solutes on the wetting behaviour of a solvent in contact with a neutral or charged planar substrate. The SPM is made up of three species of hard sphere particles with different diameters, interacting via an attractive Yukawa potential to model excluded volume and cohesion. The solvent particles are neutral, while the monovalent anions and cations are oppositely charged. The polar nature of the solvent is modelled by a continuum dielectric permittivity linked to the local solvent density. All three species interact with the impenetrable substrate via an attractive external potential. While excluded volume effects are accurately described by a Rosenfeld ‘fundamental measure’ free energy functional, the short range Yukawa attraction and Coulombic interactions are treated within the mean-field approximation. The ionic solutes are found to have a significant impact on the wetting behaviour of the solvent, in particular on the wetting temperature. Strong electric fields, or long-ranged (weakly screened) Coulombic forces are shown to have the propensity to change the wetting transition from second to first order. The cation–anion size asymmetry leads to charge separation on the liquid–vapour interface of the solution, which in turn can induce a drying transition on the liquid side of liquid–vapour coexistence.
Antioxidative and antimicrobial activity of Reynoutria japonica extracts

Ethanolic (50%, v/v) extract of Reynoutria japonica Houtt. rhizome from the Banja Luka region was prepared. The dry extract was dissolved in methanol, and total phenols content, antimicrobial and antioxidative activities were determined. The total phenols content was determined using modified Folin-Ciocalteu method, the antimicrobial activity by monitoring the optical density, and antioxidative activity by the method of quenching stable free 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals by FRAP and ABTS metods. The antioxidative activity results were compared with control antioxidants: vitamin C, BHA and BHT. In order to determine the antimicrobial extract activity, E. coli, S. aureus and B. cereus were used as test microorganisms. The paper discusses the results of antimicrobial and antioxidative activeties of the R. japonica extract with respect to extract concentration as well as to total phenols content. The extract of R. japonica rhizome shows both, a significant overall antioxidant activity (29.84 mM (FeII)/g of extract) and high activity in quenching DPPH (IC50 = = 13.68 μg/mL) and ABTS+ (99.1%) radicals. It was found that the R. Japonica extract had greater impact on growth rate reduction of B. cereus, E. coli, than S. aureus, expressed in percentages of growth rate, L, 73.6, 59.3 and 52.1% respectively. The greatest decrease in total bacterial count, M, was observed in S. aureus (71.9%), while the decrease in E. coli and B. cereus was approximately equal (about 50%). The total phenols content, expressed as mg of galic acid equivalents/g of extract was 664±15. The high antioxidant and significant antimicrobial activity of the R. japonica extract determined in this work is associated with extremely high total phenols content.
Neutron Diffraction Studies of α‐FeOOH

Neutron spectrometric investigations are made of goethite (α-FeOOH) of mineralogical and synthetic origin (α-FeOOH of natural isotopic composition) and also of α-FeOOD using a monochromatic neutron beam of λ = 1.12 A. Some powder diffraction patterns in the temperature range from −190 to +120°C are measured. The obtained coordinates for all atoms (including those for hydrogen) in the unit cell are given. The existence of antiferromagnetic spin ordering at temperatures below +80°C is observed. A model is proposed in which the spins are aligned parallel to the b-axis.
Standard enthalpies of formation of phenanthrene and naphthacene

Abstract Standard enthalpies of combustion of phenanthrene and naphthacene were determined to be − (7048.7 ± 0.9)kJ · mol − 1and − (9005.1 ± 1.8)kJ · mol − 1, respectively, by means of high-precision micro-combustion calorimetry. The former result agrees very well with that reported by Steele et al.(AIChE Symposium Series 279,1990 , 86, 138–154). The latter confirms theoretical predictions. By using standard enthalpies of sublimation from the literature, the standard molar enthalpies of formation of phenanthrene and naphthacene in the gas phase were derived to be (201.7 ± 2.9)kJ · mol − 1and (331.6 ± 4.4)kJ · mol − 1, respectively. The enthalpy of the rearrangement reaction from anthracene to phenanthrene was evaluated to be − (28.4 ± 4.1)kJ · mol − 1.
CLEARER: a new tool for the analysis of X-ray fibre diffraction patterns and diffraction simulation from atomic structural models

Fibre diffraction can provide structural information about polymers and biopolymers that is unobtainable using other methods. This method has been used to elucidate the structures of many polymers, biopolymers and protein assemblies. Extracting structural information from fibre diffraction patterns is a major challenge. A computer program called CLEARER has been developed that aids the detailed analysis of polycrystalline fibre diffraction patterns. It offers an easy-to-use interface that enables diffraction data processing, analysis and simulation of diffraction patterns. It is likely to be applicable to structural determination for a wide range of polymeric fibrous materials. CLEARER simplifies and speeds up the data analysis process and helps to utilize all of the structural information present in the analysed X-ray and electron diffraction patterns.
The Dehydration of 1,4‐Butanediol to Tetrahydrofuran in Supercritical Water

The dehydration of 1,4-butanediol to tetrahydrofuran is a reaction that possesses disadvantages under conventional conditions caused by the use of mineral acids and the corrosion problem interconnected with it. These disadvantages can be remedied by the use of pure supercritical water as reaction medium, as well as catalyst. The selectivity of the reaction regarding THF is nearly 100%. The ionic mechanism, which exists under conventional conditions, could be validated by the examinations of this work not only in the sub- but also in the supercritical range.
Electronic spectra of carbon chains and rings: Astrophysical relevance?

Abstract Our research has focused on the measurement of the electronic spectra of unstable molecules which are presumed to be of relevance to astrophysical observations. Among these are the carbon chains and their ions. Thus we have been using and developing a number of spectroscopic methods to determine their spectra in the gas phase, including absorption via cavity ring-down and REMPI methods. The species are produced in supersonic jets coupled with discharge and laser ablation sources. With the successful laboratory detection of the electronic spectra of a number of key species, such as bare carbon chains Cnn=4,5, comparisons with astrophysical data could be made which lead to interesting implications for the future search for the species which could be responsible for the diffuse interstellar bands. Among the recent relevant observations in the laboratory have been the electronic spectra of carbon rings, Cnn=14,18,22, the development of a method to study transitions in mass-selected ions collisionally relaxed to 20 K and held in a 22-pole radiofrequency trap, and the study of metal containing carbon chains.
Monitoring plasma impedance match characteristics in a multipole inductively coupled plasma for process control

A real-time system is presented to monitor impedance match characteristics of a recently manufactured etch system, where a low pressure planar plasma is provided using multipole magnetic cores. Apart from typical radio-frequency (rf) parameters, the system particularly monitors match positions for the diagnosis of plasma impedance. Sensitivities of match positions to factor variations were examined. Statistical analysis was performed over transient match data to extract further diagnostic clues. Using a real-time rf sensor, meanwhile, match positions were correlated to plasma impedance. The process factors that were varied in the experiments include source power, pressure, Ar, and O2 flow rates. A sublinear relationship was found between each position and source power with much lessened match sensitivity in Ar or O2 flows. Phase match position demonstrated an enhanced sensitivity over impedance match position. Statistical mean analysis of transient match data enabled further detection of shifts in plasma .
Synthesis of Ultra-high Weight Average Molecular Mass of Poly-L-lactide

High purity in high yield L-lactide was prepared using a new purification method, and poly-L-lactide (PLLA) with ultra-high weight average molecular mass and narrow polydispersity index was synthesized by ring-opening polymerization. The effects of the purification method on the purity and yield of L-lactide were investigated, and the influences of initiator concentration, polymerization temperature and polymerization time on the weight average molecular mass of PLLA were also studied. A synthetic purification method involving a water bath and two times recrystallization could improve the purity of L-lactide to 100%. The yield of L-lactide reached 40.6% and increased 12.1% compared with the recrystallization method. Poly-L-lactide with a weight average molecular mass of about 102.4 × 104 and a polydispersity index of 1.16 was obtained when polymerization was conducted with molar ratio of monomer to initiator ([M]/[I]) of 12000 for 24 h at 140°C.
Simulation studies of at high pressure

The negative thermal expansion recently observed over a wide range of temperatures in the ambient pressure phase was attributed to the existence of low-frequency phonon modes which propagate with minimal distortion of the tetrahedra and octahedra, the so-called `rigid unit modes'. The flexibility afforded this structure by these modes raises questions about the structure's behaviour with pressure. Further experiments found a high-pressure phase which also exhibited negative thermal expansion. Calculations using the rigid unit mode model have shown that the mechanism described earlier in the context of is consistent with the negative thermal expansion in . Atomistic simulations have been used to calculate further properties of these two phases (e.g. transition pressure, compressibilities) using interatomic potentials derived for the earlier work on . The reproduction of the cell parameters and bond lengths measured for does not imply a substantial change in the bonding character of the W-O interactions.
CONTINUOUSLY TUNABLE EXTENDED CAVITY DIODE LASER AT 780 nm FOR HIGH RESOLUTION SPECTROSCOPY

In this communication we have investigated and compared the tuning abilities of an ECDL system, using a grating in Littrow configuration, depending on the laser diode (LD) used. We have achieved experimentally a wide continuous frequency tuning range by applying translation-rotational movement of the grating together with appropriate injection current correction. The fluorescence spectrum of Rb in the vicinity of 780 nm has been recorded in an external absorption cell. The wide mode-hop free frequency tuning gave us the possibility to reach exactly the maximum of each fine component of the Rb D2 line. By scanning the applied magnetic field strength, sub-natural width resonance (SNWR), with FWHM in the kHz range, have been observed in the fluorescence signal and in the transmitted output power. Such resonance is very appropriate for measuring weak magnetic fields.
Stability of ruthenium nanoparticles synthesized by solvothermal method

One of the major obstacles to the synthesis of nanoparticles and nanocatalyst is the stability of particles. In the present study, polymer stabilized ruthenium nanoparticles were synthesized by solvothermal method using solutions of ruthenium chloride in ethylene glycol in presence of poly(N ‐vinyl‐2‐pyrrolidone) (PVP) as a stabilizing agent. Stability of nanoparticles was studied by varying different parameters e.g. PVP/RuCl3 molar raio, RuCl3 concentration, reaction temperature and time and expressed in terms of particle size and size distribution. Transmission electron microscope (TEM) analysis revealed the presence of metallic clusters with a uniform size of about 20‐65 nm. Dispersion destabilisation of colloidal nanoparticles was detected by Turbiscan. Polymer stabilized ruthenium nanoparticles were dispersed on γ‐alumina to prepare uniformly disperse Ru/γ‐Al2O3 catalyst by mechanical strirring and sonication. Inductively coupled plasma‐optical emission spectroscopy (ICP‐OES), X‐Ray powder diffraction (XRD), Transmission electron microscopy (TEM) and Thermo gravimetric analysis (TGA) were used to characterize the supported catalyst. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthese von optisch aktiven, natürlichen Carotinoiden und strukturell verwandten Naturprodukten. VIII. Synthese von (3S,3′S)‐7,8,7′,8′‐Tetradehydroastaxanthin und (3S,3′S)‐7,8‐Didehydroastaxanthin (Asterinsäure)

Synthesis of Optically Active Natural Carotenoids and Structurally Related Compounds. VIII. Synthesis of (3S,3′S)-7,8,7′,8′-Tetradehydroastaxanthin and (3S,3′S)-7,8-Didehydroastaxanthin (Asterinic Acid) The synthesis of all-trans-(3S,3′S)-3,3′-dihydroxy-7,8, 7′,8′-tetradehydro-β, β-carotene-4,4′-dione (1), of all-trans-(3S,3′S)-3,3′-dihydroxy-7, 8-didehydro-β,β-carotene-4,4′-dione (2) (asterinic acid = mixture of 1 and 2), and of their 9,9′-di-cis- and 9-cis-isomers is reported starting from (4′S)(2E)-5-(4′-hydroxy-2′, 6′,6′-trimethyl-3′-oxo-l′-cyclohexenyl)-3-methyl-2-penten-4-ynal (8). The absolute configuration (3S,3′S) for both components 1 and 2 of asterinic acid ex Asterias rubens is confirmed on the basis of spectroscopic and direct comparison.
Generation of charged drops of insulating liquids by electrostatic spraying

Development of a new method for the generation of microparticles of controlled size and charge is reported. The method, which is particularly suited for insulating liquids, is to generate stable fine jets through electrostatic spraying. Charge in the liquid is produced by placing a sharp electrode inside the liquid and raising it to a high potential. High electric fields then disrupt the liquid to form fine jets which later break up into small drops. A theoretical explanation of these phenomena is presented and compared with experimental results with a qualitatively good agreement. Among the possible applications of this work is generation of cryogenic droplets for refueling fusion reactors and for laser fusion targets.
A New Monolithic‐Type HPLC Column For Fast Separations

Summary The application of a new silica-based, monolithic-type HPLC-column for fast separations is presented. The column is prepared according to a new sol-gel process, which is based on the hydrolysis and polycondensation of alkoxysilanes in the presence of water soluble polymers. The method leads to “rods” made of a single piece of porous silica with a defined pore structure, i. e. macro- and mesopores. The main feature of silica rod columns is a higher total porosity, about 15% higher than of conventional particulate HPLC columns. The resulting column pressure drop is therefore much lower, allowing operation at higher flow rates including flow gradients. Consequently, HPLC analysis can be performed much faster, as it is demonstrated by various applications.
KINETICS OF LACTIC ACID EXTRACTION WITH QUATERNARY AMMONIUM SALT

Extraction and stripping kinetics of lactic acid in extractive fermentation were studied using tri-n-octylmethylammonium chloride, a quaternary ammonium salt, as an extractant and oleyl alcohol as a diluent. The kinetic analysis was performed through simulated time course studies of lactate concentration in both the extraction and stripping phases. Dependences of extraction rate on initial lactate and extractant concentrations and those of stripping rate on initial chloride and extractant-lactate complex concentrations were examined. Because diffusion through the organic film was a rate-controlling step, the experimental results of both extraction and stripping could be explained well by a simple equation.
Fungus-mediated synthesis of silver nanoparticles and their immobilization in the mycelial matrix: a novel biological approach to nanoparticle synthesis

A novel biological method for the synthesis of silver nanoparticles using the fungus Verticillium is reported. Exposure of the fungal biomass to aqueous Ag+ ions resulted in the intracellular reduction of the metal ions and formation of silver nanoparticles of dimensions 25 ± 12 nm. Electron microscopy analysis of thin sections of the fungal cells indicated that the silver particles were formed below the cell wall surface, possibly due to reduction of the metal ions by enzymes present in the cell wall membrane. The metal ions were not toxic to the fungal cells and the cells continued to multiply after biosynthesis of the silver nanoparticles.
Ion pairing in model electrolytes: A study via three-particle correlation functions

A novel integral equations approach is applied for studying ion pairing in the restricted primitive model electrolyte, i.e., the three-point extension (TPE) to the Ornstein–Zernike integral equations. In the TPE approach, the three-particle correlation functions g[3](r1,r2,r3) are obtained. The TPE results are compared to molecular dynamics (MD) simulations and other theories. Good agreement between TPE and MD is observed for a wide range of parameters, particularly where standard integral equations theories fail, i.e., low salt concentration and high ionic valence. Our results support the formation of ion pairs and aligned ion complexes.
Microwave-Assisted Hydrothermal Synthesis of Brookite Nanoparticles from a Water-Soluble Titanium Complex and Their Photocatalytic Activity

Nanoparticles of brookite titanium oxide were prepared by microwave-assisted hydrothermal (MH) method at 200°C (heating time 5 min) for 0-60 minutes starting from the titanium peroxo glycolate complex in basic solution. The effect of microwave heating on the morphology of the brookite particles was examined. The samples were characterized by X-ray diffraction (XRD), Raman spectroscopy and transmission electron microscopy (TEM). It was found that all powders were composed of single phase brookite and contained two different types of particles. The activity in photodecomposition of oxalic acid by the samples prepared using MH method was higher than activities of brookite nanoparticles synthesized by the conventional hydrothermal method.
Optimization and Miniaturization of a Fiber-Optic ф-OTDR Distributed Vibration Sensor

This thesis evaluated the performance of a portable Phase Optical Time-domain Reflectometer (φ-OTDR) system employed as a distributed vibration sensor. Firstly, the technique was studied and a literature review was performed. Then, a miniaturized φ-OTDR was built and tested, in order to be capable to perform on-field measurements. In order to test the capacity limits of the developed sensor, a poled fiber was inserted in the optical fiber under test and sinusoidal signals of different frequencies were applied, testifying a capability of the system to measure frequencies up to 80 kHz. Furthermore, a Fiber Bragg Grating (FBG) array was inserted in the fiber under test, aiming to investigate the interaction between both sensing techniques, which resulted in vibration measurements with higher signal-to-noise ratio and the capability to remove an amplifier from the miniaturized distributed sensor, reducing its total cost. Lastly, the portable sensor was evaluated on a field trial, where it was capable to detect vibrations in rotating bearings.
Specific antiserum staining of two‐dimensional electrophoretic patterns of human plasma proteins immobilized on nitrocellulose

Human plasma proteins separated by high‐resolution two‐dimensional electrophoresis have been electrophoretically transferred to sheets of nitrocellulose using a modification of the method of Towbin, Staehelin, and Gordon [8]. Although the proteins have been denatured in sodium dodecyl sulfate and separated into subunits, the nitrocellulose‐bound molecules still react with appropriate specific antisera even after storage of the transfer in air at room temperature for 5 months. Of 25 proteins whose location in the pattern had been previously determined, 24 are specifically revealed on transfers of whole plasma patterns by appropriate antiserum. In addition, 6 previously unidentified proteins (prothrombin, C1s, C4γ, C1s inhibitor, Ig J‐chain, and a1AP glycoprotein) have been identified in the pattern for the first time using the transfer technique. It therefore seems likely that a large majority of proteins (> 96 % in this study) retain sufficient conformation throughout the analytical procedure (or can regain it easily afterwards) to be recognized immunologically. The transfer technique thus constitutes a generally useful immunological “third‐dimension” in the high‐resolution separation of proteins. Of three monoclonal antibodies similarly tested, none could detect antigen transferred to nitrocellulose from a two‐dimensional gel, while each bound specifically to the appropriate antigen absorbed in native form to the nitrocellulose.
Multiscale molecular simulations of the nanoscale morphologies of P3HT:PCBM blends for bulk heterojunction organic photovoltaic cells

In this study, we developed a multiscale molecular simulation framework including coarse-grained (CG) molecular simulation, reverse-mapping, and morphology evaluation schemes to investigate the nanoscale morphologies of bulk heterojunction (BHJ) blend films comprising poly(3-hexylthiophene) (P3HT) and the methanofullerene derivative PCBM. A stable and phase-separated blend film with the fibrillar P3HT structure was observed after CG simulation of the thermal annealing process, and by the reverse-mapping technique the atomistic details—showing strong π–π interaction between thiophene rings—were retrieved. To evaluate the morphologies of P3HT:PCBM blends, a spatial-discretization scheme was developed. With such a scheme, we estimated the average domain sizes, interface-to-volume ratios, and percolation ratios of the blends at different P3HT:PCBM weight ratios. The average domain sizes determined through these simulations were in excellent agreement with those reported experimentally. Moreover, our simulations indicated that blend films having weight ratios close to 1 : 1 would have the highest interface-to-volume ratio and the most balanced charge carrier transport in both the P3HT and PCBM phases, consistent with the experimental observation that a 1 : 1 weight ratio is optimal for P3HT:PCBM blends. The multiscale molecular simulation framework proposed herein can be extended to investigating the morphologies of other photoactive layers of organic photovoltaic cells.