Miracle-dz/UniFAR-FTUs huggingface dataset:
Influence of Drying Time and Process on Artemisia herba-alba Asso Essential Oil Yield and Composition

Abstract The essential oil content of Artemisia herba-alba Asso decreased along the drying period from 2.5 % to 1.8 %. Conversely, the composition of the essential oil was not qualitatively affected by the drying process. The same principle components were found in all essential analyzed such as α-thujone (13.0 – 22.7 %), β-thujone (18.0 – 25.0 %), camphor (8.6 - 13 %), 1,8-cineole (7.1 – 9.4 %), chrysanthenone (6.7 – 10.9 %), terpinen-4-ol (3.4 – 4.7 %). Quantitatively, during the air-drying process, the content of some components decreased slightly such as α-thujone (from 22.7 to 15.9 %) and 1,8-cineole (from 9.4 to 7.1 %), while the amount of other compounds increased such as chrysanthenone (from 6.7 to 10.9 %), borneol (from 0.8 to 1.5 %), germacrene-D (from 1.0 to 2.4 %) and spathulenol (from 0.8 to 1.5 %). The chemical composition of the oil was more affected by oven-drying the plant material at 35°C. α-Thujone and β-thujone decreased to 13.0 %and 18.0 %respectively, while the percentage of camphor, germacrene-D and spathulenol increased to 13.0 %, 5.5 %and 3.7 %, respectively.
Complexation of steroid hormones: prednisolone, ethinyloestradiol and estriol with β-cyclodextrin. An aqueous 1H NMR study

The inclusion complexes of β-cyclodextrin (β-CD) with prednisolone 1, ethinyloestradiol 2 and estriol 3 in aqueous solution were investigated using 1H NMR and molecular modelling. The NMR spectra of the steroids studied in the presence of β-CD are fully assigned and interpreted by means of 2D GCOSY and NOESY spectra. The parallel interpretation of β-CD chemical shift changes and dipolar contacts allows the mode of binding to be established. On the basis of ROESY data, the “low resolution” β-cyclodextrin complexes of 1, 2 and 3 have been determined by multistep restrained molecular dynamics calculations. Calculated structures of β-cyclodextrin complexes with 1, 2 and 3 fully agree with experimental data. Combined approaches allow the distinction of weak nonspecific binding for 1 as compared to stronger, “through cavity”, inclusion established for 2 and 3.
Molecular dynamics study of reaction kinetics in viscous media

Predicted by stochastic models and observed experimentally in a number of isomerization reactions, viscosity-induced solvent effects manifest themselves in a significant departure of the reaction rates from the values expected on the basis of transition state theory. These effects are well understood within the framework of stochastic models; however, the predictive power of such models is limited by the fact that their parameters are not readily available. Experiment and molecular dynamics (MD) simulations can provide such information and can serve as the testing grounds for various stochastic models. In real solvents, a change in viscosity is inevitably associated with variation of at least one of the three factors – temperature, pressure, or solvent identity, resulting in different solvent–solvent and solvent–solute interactions. A model is proposed in which solvent viscosity is manipulated through mass scaling, which allows one to maintain other factors constant for a series of viscosities. This approach was tested on MD simulations of the kinetics of two model isomerization reactions in Lennard–Jones solvents, whose viscosity was varied over three orders of magnitude. The results reproduce the Kramers turnover and a strong negative viscosity dependence of the reaction rates in the high viscosity limit, somewhat weaker than η −1.
MICELLAR EXTRACTION AND CLOUD-POINT PRECONCENTRATION OF LABDANE DITERPENOIDS FROM ANDROGRAPHIS PANICULATA

Micelle-mediated extraction and cloud-point preconcentration method was developed for the separation and determination of andrographolide (ANDRO) and neo-andrographolide (NEO) from Andrographis paniculata by planar and high performance liquid chromatography with photodiode array detection. Comparative efficiency and feasibility of employing non-ionic surfactants, namely, Triton X-100, Triton X-114, and Genapol X-80 as an alternative and effective solvent have been demonstrated. Ultrasonic assisted extraction, when compared with common organic solvents, at 5% surfactant (Triton X-100) concentration has yielded higher extraction efficiency of ANDRO and NEO than common organic solvents. The preconcentration factor was approximately 7.0 and the cloud-point extraction recoveries for the two labdane diterpenoids were 90.28 and 98.80%, respectively. The HPLC method consisting monolithic column and isocratic elution with water: acetonitrile (75:25, v/v) has shown advantages over C18 column, in terms of noninterference of surfactant peak elution. The elution was monitored with a photodiode array detector and quantitation was performed at 220 nm. The method has shown good sensitivities (LOD- 10, 30 µg/mL; LOQ- 33, 99 µg/mL of ANDRO and NEO, respectively). The results showed that micelle-mediated extraction and cloud-point preconcentration could be employed as an alternative and ecofriendly approach for the rapid analysis of targeted diterpenoids from A. paniculata.
Graphene: a multipurpose material for protective coatings

Graphene based materials have attracted great interest in the development of new and advanced protective coatings due to their excellent chemical resistance, impermeability to gases, adsorption capacity, anti-bacterial properties, mechanical strength, lubricity and thermal stability. This review presents current progress and discusses the major challenges and future potential of graphene in the field of protective coatings. This review specifically focuses on the most recent advances in the application of graphene for corrosion resistant coatings, flame retardant coatings, wear/scratch resistant coatings, anti-fouling coatings, pollutant adsorption coatings and anti-septic coatings.
SIMS INVESTIGATIONS OF GETTERING CENTERS IN ION-IMPLANTED AND ANNEALED SILICON

ABSTRACT High-energy ion implantation in silicon leads to the formation of defects around the mean projected ion range R p. These defects are capable of collecting unwanted impurities like metal atoms. A similar effect has been observed in the depth range around half of the projected ion range, R p/2. This gettering ability around R p/2 is supposed to rely on excess vacancies, generated by the implantation process itself. SIMS is a preferential tool in the detection of gettering centres: If copper is applied at the backside of the sample and trapped in the gettering layers during annealing, enrichments of copper in certain areas can be seen in SIMS depth profiles [1]. If the R p/2-effect was caused by excess vacancies, then one attempt to remove these additional gettering centres would be to implant additional Si atoms which could recombine with the vacancies: In order to test this assumption, three Si+ implanted samples were implanted with additional Si+ ions having a projected range that corresponds to R p/2. After application of copper and annealing, the copper distribution was investigated by SIMS. Furthermore a low-energy-He+-implanted silicon wafer was examined, showing that He+ implantation not only leads to an accumulation of metals but also of oxygen in the R p and R p/2 range.
Reducción de percloroetileno Y cromo hexavalente mediante Fe(0) Y bioestimulación de microorganismos anaerobios

Fe-microorganisms interactions in and around permeable reactive barriers, for reduction of perchloroethylene and hexavalent chromium in polluted aquifers were examined. Biostimulation was done by the addition of a co-substrate for microbial communities already present in the soil. An hydrogen release compound (HRC), a commercial cosubstrate which releases lactic acid at slow rates in presence of water was selected. Results show that HRC addition increases (>100 %) the reduction of PCE in iron-containing systems. Nevertheless, reductive dechlorination was not complete and caused accumulation of toxic metabolites such as trichloroethylene. For chromium reduction, bioestimulation enhanced reduction capability of the systems by 20 %. In this case, the effect was not stimulation of Cr-reducers, but the improvement of redox conditions.
Infrared and Raman Spectra of the Cellulose from the Cell Wall of Valonia ventricosa

Comparison of the laser‐Raman spectra with the polarized infrared spectra of native cellulose from the cell walls of the algae Valonia ventricosa has allowed greater confidence to be placed on the vibrational assignments than was possible previously from infrared data alone. The major details of the chain conformation and packing are already known from x‐ray and electron diffraction studies, but the relative chain polarities and the nature of the intra‐ and intermolecular hydrogen bonding remain unknown. The present work indicates that only one rotational conformation is present for the −CH2OH side chains, which reduces considerably the number of structural possibilities.
Tailoring Electronic and Magnetic Properties of MoS2 Nanotubes

We have studied the electronic and magnetic structures of MoS2 nanotubes by using a first-principles method. Various kinds of defects such as substitution and vacancy are examined for triggering spin magnetic moments toward one-dimensional diluted magnetic semiconductors. Our results suggest that the presence of impurity states within the energy gap and its large contribution to the density of states at the Fermi level are the key factors in inducing a magnetic moment. In particular, the nanotube curvature turns out to affect the energy level of impurity states, which can be exploited for tailoring magnetic properties. Also, 3d transition metal impurities (V, Mn, Fe, and Co atoms) on a Mo site can create large magnetic moments.
Comparison of deep levels in GaN grown by MBE, MOCVD, and HVPE

Deep levels in n-type GaN grown by molecular beam epitaxy, metalorganic chemical vapor deposition, and hydride vapor phase epitaxy were characterized for comparison between the different methods of growth. The deep level energies, capture cross sections, and concentrations were determined for each using deep level transient spectroscopy on Schottky diodes from 80 K to 700 K, to characterize traps up to ~1.2 eV. The capture kinetics and bias dependence were also measured for the main traps in each, in order to determine if they are related to threading dislocations, and if they are donor-type traps. Several traps were detected in samples from each growth method. The field dependence and the capture kinetics were not the same for peaks appearing in the same temperature in deep level spectra, associated with different growth method. Traps in HVPE GaN at 0.212 eV and 0.612 eV uniquely showed field dependence indicating singly charged donors. Overall, the thick hydride vapor phase epitaxy GaN samples showed the lowest concentration of traps.
Synthesis and Molecular Characterization of Polythiophene Block Co-, Ter-Polymers and Four-Arm Star Homopolymer

Abstract We report the synthesis of polythiophene (PT) block copolymers with polystyrene (PS) or polyisoprene of increased 3,4 microstructure (PI3,4) and triblock terpolymer of the PS-b-PI-b-PT type. Tetrathienylsilane (C16H12S4Si) was also prepared in order to react with thiophene and eventually synthesize a four-arm star PT homopolymer. The preparation of the functional precursors and intermediate products (PS, PI, PS-b-PI3,4, and C16H12S4Si) was achieved through high vacuum techniques, and PT was synthesized under ambient conditions via the corresponding chemical oxidative polymerization reaction. The final polymers and the intermediate precursors were molecularly characterized by size exclusion chromatography (SEC), membrane osmometry (MO), proton nuclear magnetic resonance (1H-NMR), and carbon nuclear magnetic resonance (13C-NMR) spectroscopies.
Long‐term stability of dye‐sensitised solar cells

Accelerated ageing tests on large numbers of nanocrystalline dye‐sensitised solar cells (nc‐DSC) show that, to first order, separation between the effects of the stresses of visible light soaking, UV illumination and thermal treatment on long‐term stability is possible. The corresponding mechanisms are electrochemical, photochemical and purely chemical in nature. It was found that visible light soaking alone is not a dominant stress factor. A dramatic improvement in UV stability has been achieved by using MgI2 as additive to the electrolyte. Thermal stress appears to be one of the most critical factors determining the long‐term stability of nc‐DSC and is strongly related to the chemical composition of electrolyte solvents and additives. Encouraging stability results have been obtained for cells based on pure nitrile‐based solvents: (1) A minor decrease in performance of initially 5.5% solar efficient cells has been found after 2000 h at 60°C without light soaking; (2) After 900 h ageing at 85°C, a decrease of 30% in maximum power has been observed; (3) After 3400 h of combined thermal stress and continuous light soaking (45°C, 1 sun equivalent) good stability with 15% decrease in maximum power can be demonstrated. It should be noted that such good thermal stability has not been reported previously for dye‐sensitised solar cells so far. Copyright © 2001 John Wiley & Sons, Ltd.
Phase relations among tellurides, sulfides, and oxides; I, Thermochemical data and calculated equilibria

Thermodynamic data for binary tellurides are compiled and combined with available data for sulfides and oxides to calculate phase relations among tellurides, sulfides, and oxides at low temperatures (100 degrees -300 degrees C). Limits on the natural range in f (sub Te 2 ) , f (sub S 2 ) , and f (sub O 2 ) values during telluride deposition and/or reequilibration are estimated from natural assemblages relative to reactions, such as 2Fe 3 O 4 + 3S 2 + 3Te 2 = 3FeS 2 + 3FeTe 2 + 4O 2 and 2HgS + Te 2 = 2HgTe + S 2 . Calculated equilibria show that tellurides of Mo, Sn, Mn, and Zn are unstable with respect to corresponding sulfides and/or oxides in natural systems and that some tellurides, such as As 2 Te 3 , are likely to occur in nature, although they have not yet been found as minerals. The composition of electrum in equilibrium with hessitc is useful as a sliding-scale indicator of the fugacity of Te 2 at relatively low values of f (sub Te 2 ) . The calculated phase relations explain particular associations or antipathies among ore minerals and may be used to predict other minerals which should be present at equilibrium.
Numerical Determination of Two-Phase Material Parameters of a Gas Diffusion Layer Using Tomography Images

In this paper, we give a complete description of the process of determining two-phase material parameters for a gas diffusion layer: Starting from a 3D tomography image of the gas diffusion layer the distribution of gas and water phases is determined using the pore morphology method. Using these 3D phase distributions, we are able to determine permeability, diffusivity, and heat conductivity as a function of the saturation of the porous medium with comparatively low numerical costs. Using a reduced model for the compression of the gas diffusion layer, the influence of the compression on the parameter values is studied.
M2B5 or M2B4? A Reinvestigation of the Mo/B and W/B System

Abstract. The literature states different compositions (M/B 1:2 vs. 2:5) and structures for diborides of molybdenum and tungsten.Using X-ray and neutron powder diffraction as well as energy andwavelength dispersive electron microprobe analysis, the Mo/B andW/B systems were now reinvestigated. Molybdenum diboride cry-stallizes as a stoichiometric compound Mo 2 B 4 (formerly describedas Mo 2 B 5 ) in space group R 3¯ m (No. 166, a , b 3.01375(2) A˚ , c 20.9541(3) A˚ ), and as a non-stoichiometric compound MoB 2 x (formerly described as MoB 2 )in P 6 /mmm (No. 191, a , b Introduction For the Mo/B and W/B system, compounds like MB, MB 2 ,M 2 B 5 ,M 0.8 B 3 , and MB 4 are reported in the literature. Suchcompounds have interesting electrical and mechanicalproperties, which indicate possible applications as high-tem-perature ceramic materials [1 7]. Recently, Telle et al.showed that W 2 B 5 -based materials display unique fracturebehaviours and delamination phenomena [6, 8 10]. The first one to structurally characterize the dimetalpentaborides Mo
Enhanced Catalytic Combustion Using Sub-micrometer and Nano-size Platinum Particles

Sub-micrometer and nano-size catalytic particles are significantly more reactive than their bulk counterparts and can be used to enhance the performance of catalytic combustors. Their high specific surface areas (typically 1−200 m2/g) and unique morphologies contribute to their enhanced reactivity. Differences in adsorbed species and/or their distributions may also play an important role yet are not clear. The purpose of this study is to quantify the effects of particle size, catalyst loading, and flow residence time on the reactivity of methanol−air premixtures over dispersed platinum (Pt) nanoparticles. As such, experiments were conducted in an atmospheric flow tube reactor seeded with 2−5, 200, and 500 nm Pt particles distributed on a substrate made from deactivated fused silica wool. Temperature measurements and exhaust gas species analyses were obtained for the different size particles, catalyst loadings, and flow conditions. Materials characterization of the particles was also conducted, and scannin.
Kinetics of Natural Organic Matter as the Initiator, Promoter, and Inhibitor, and Their Influences on the Removal of Ibuprofen in Ozonation

Natural organic matter (NOM) can simultaneously act as the initiator, promoter and inhibitor in water ozonation. This study presents an explicit method that can be used to determine these rate constants via the integration of the transient steady-state hydroxyl radical (•OH) model, the Rct concept and the pseudo first-order ozone decomposition model. The theoretical background of this method was provided, and the method was validated with model compounds. The rate constants of three NOM isolates were determined using the developed method. With these rate constants, the influences of NOM on the degradation of ibuprofen, an •OH-reactive pharmaceutical compound, can be quantitatively described. [Supplementary materials are available for this article. Go to the publisher's online edition of Ozone Science & Engineering for the following free supplemental resources: tables, figures, and equations. ]
Surfactant-assisted growth of uniform nanorods of crystalline tellurium

Uniform tellurium single crystal nanorods with diameters of 14 nm and lengths of 300 nm were prepared through reduction of [TeS4]2− by SO32− with use of a suitable surfactant, sodium dodecyl benzenesulfonate (NaDDBS). Te nanorods with various diameters can be prepared by carefully adjusting the concentration of NaDDBS or the initial concentration of TeS42−. The nucleation and growth processes of Te nanorods were interpreted by solid–solution–solid transformation and surfactant-assisted growth mechanism.
Hygroscopic mineral dust particles as influenced by chlorine chemistry in the marine atmosphere

Morphology and elemental compositions of individual dust particles were investigated with the use of Asian dust samples collected at a site along the Sea of Japan side of the archipelago. Our results indicate the preferential formation of chloride in Ca‐containing dust particles (0.1 < Cl/Ca < 0.65) in cases when the particles contain little or no sulfate. Most of them are in an amorphous state and nearly spherical even under high vacuum. A likely explanation for the results is that highly soluble salts such as calcium chloride (CaCl2) are formed as a result of heterogeneous reactions of dust particles with chloride precursor gases (mostly, HCl) in the marine atmosphere. The chloride formation is expected to play an important role in enhancing the hygroscopicity of dust particles.
State selective population of H2(v″=1, J″=1) and D2(v″=1, J″=2) and rotational relaxation in collisions with H2, D2, and He

Single rotational states were populated in vibrationally excited hydrogen by stimulated Raman pumping. The population in H2 X 1∑+g(v″=0,1) and D2 X 1∑+g(v″=0,1) was probed state selectively by tunable vacuum ultraviolet (VUV) laser radiation around λ=110 nm, and the fluorescence induced when exciting the hydrogen molecules in the (0–0), (1–0), (2–0), (3–1), and (4–1) Lyman bands of the (B 1∑+u←X 1∑+g) transition monitored. From a comparison of line heights, the stimulated Raman pumping efficiency is estimated to be 30%–50% in the focal volume. Rotational transitions in X 1∑+g(v″=1) were induced in collisions with H2, D2, and He. State‐to‐state rotational relaxation rates were measured for the (J″=1→J″=3) transition in H2(v″=1) and for the (J″=2→J″=0,4) transitions in D2(v″=1). These rates were found to be generally higher than the corresponding previously determined ones in ground state hydrogen, in qualitative accord with recent theoretical calculations. A comparison with available theoretical state‐to‐s.
Lateral structures of thin films of ampholytic diblock copolymers adsorbed from dilute aqueous solution at the solid/liquid interface

The lateral structures of dried thin films of the ampholytic diblock copolymer poly((methacrylic acid)-block-((dimethylamino)ethyl methacrylate)) adsorbed from dilute aqueous solution onto silicon substrates were investigated by scanning force microscopy (SFM) and diffuse X-ray scattering. The adsorbed amount of polymer, as a function of pH, reveals a maximum near the isoelectric point (IEP) of the polyampholyte. Different lateral structures are determined for samples adsorbed at pH values above the maximum of the adsorbed amount, as compared to the ones adsorbed at pH values below this maximum. At a pH around the IEP, the polyampholyte precipitates and the layers are formed by adsorption of flocks with sizes in the micrometer range. Lateral structures measured by SFM are similarly detected by diffuse X-ray scattering. The later technique delivers a statistical description of the lateral surface structures averaged over a larger area. The structures investigated are related to the polyampholyte structure .
Ab initio calculation of atomic axial tensors and vibrational rotational strengths using density functional theory

We document a new density functional theory (DFT) methodology for the ab initio calculation of atomic axial tensors (AATs) using direct, analytical derivative methods and gauge-invariant atomic orbital (GIAO) basis sets. AATs are calculated for ethylene oxide. Their accuracy is assessed using AAT sum rules and the experimental electric dipole moment and paramagnetic susceptibility tensor. AATs calculated for the chiral molecule 6,8-dioxabicyclo[3.2. 1]octane, in combination with DFT harmonic force fields and atomic polar tensors, are used to predict vibrational rotational strengths and vibrational circular dichroism (VCD) spectra. Their accuracy is assessed by comparison with the experimental rotational strengths and VCD spectrum.The dependence of calculated results on density functional and basis set is explored. The DFT calculations are compared to SCF (Hartree-Fock) calculations carried out in parallel.
Kinetics of interaction of palm ethyl biodiesel with three different polymer materials

Diesel diffuses into neoprene matrices 10% faster than palm ethyl biodiesel at 20°C. In contrast, the palm biodiesel soaks highly plasticized PVC five times faster than diesel. Phthalate plasticizer leaks from the PVC matrix 14 times faster when biodiesel is the absorbed liquid, relative to petrodiesel. This biodiesel penetrates polybutadiene-styrene resins at rates that depend on the ratio of phenyl to CHCH units in the resins. Copyright © 2008 John Wiley & Sons, Ltd.