Miracle-dz/UniFAR-FTUs huggingface dataset:
Influence of drying and storage on the lipophilic antioxidants content in rapeseed

During storage, lipids contained in seeds undergo adverse chemical and biochemical processes. The range of these transformations is conditioned mainly by the presence of water and also by the content of natural antioxidants. Among the lipophilic antioxidants occurring in the seeds of oil plants — also rape — are: tocochromanols (-T), plastochromanol-8 (PC-8) and β -carotene. In our climatic zone, the harvested rape seeds require additional drying until their moisture content drops to below 7%. The moisture content of 5–6% is considered the optimum due to high mechanical resistance of the stored seeds, resistance to microorganisms etc. Also the influence of these processes upon the native lipohilic antioxidants significantly determining the stability of lipids in the stored seeds, is of importance. The aim of this study was to investigate the influence of preliminary seed drying — in high as well as in low air temperatures — on the content of natural lipophilic antioxidants immediately after the harvest and after one-year storage. Two rape varieties were considered — Lisek and Kronos (00). Drying temperatures ranged from 60 up to 120°C and also some low air temperatures were applied. After reaching ca 6% moisture content, the seed samples were stored for a year at 18±1°C in darkness. After 12 months, tocopherols, PC-8 and β -carotene were determined again. Qualitative separation and quantitative determination of antioxidants in seeds were carried out by HPLC. It was noted that drying after the harvest resulted in ca 10% total tocopherol loss, and a year storage caused further loss of 50% of these compounds. Similar values were determined for PC-8 (ca 55% in relation to the original content). The smallest loss was determined for β -carotene, and its content in both varieties, Lisek and Kronos, did not exceed 35% and was the lowest in seeds dried at 60°C.
One-Electron Oxidation Reactions of Some Purine and Pyrimidine Bases in Aqueous Solutions. Electrochemical and Pulse Radiolysis Studies

The reduction potentials of some purine and pyrimidine bases and the guanine nucleoside and nucleotide at pH values between 7 and 13 were investigated using the techniques of cyclic voltammetry, differential pulse polarography, and pulse radiolysis. The results clearly show that the lowest reduction potentials, in volts vs NHE, at pH 7 are those of xanthine, 0.88 V, and 1-methylguanine, 1.06 V (NHE). The extrapolated value of guanine is ca. 1.0 V. We also studied the one-electron oxidation reaction of the azide radical with the above compounds. We monitored their transient absorption spectra and determined their formation second-order rate constants. The decay kinetics of these radicals was followed. Radicals derived from the bases decayed via a radical−radical mechanism with a second-order rate constant. However, the guanine nucleosides and nucleotide radicals have shown at all pHs two consecutive processes (first order followed by a second order). The first-order reaction is pH dependent. Formation of a.
Rayleigh and Raman scattering from optically active molecules

The intensity of Rayleigh and Raman scattering from optically active molecules is shown to be slightly different in right and left circularly polarized incident light. The circular intensity differential of the Rayleigh line is dependent on components of the optical activity tensor, and that of the Raman lines is a function of the variation of the optical activity with the vibrational coordinates. This circular intensity differential might be of the order of 10-3 times that of the Rayleigh or Raman intensity.
On the Purity of Laboratory-Generated Sulfuric Acid Droplets and Ambient Particles Studied by Laser Mass Spectrometry

ABSTRACT Particle analysis by laser mass spectrometry (PALMS) was used to examine sulfuric acid particles representative of stratospheric sulfate aerosols (SSAs) and ambient tropospheric aerosols. Sulfuric acid particles were generated in the laboratory by condensing sulfuric acid vapors in a flow stream of particle-free dry air or nitrogen. The purest particles were produced using filtered, high-purity nitrogen in a clean glass and stainless steel system. In contrast, generation techniques using filtered compressed air, Tygon tubing, or Viton o-rings resulted in detectable organic impurities in the positive ion spectra of sulfuric acid droplets. With the PALMS instrument, the lower limit of our detection of organics is at most 0.02 wt% α-tocopherol in sulfuric acid, which in terms of surface coverage corresponds to less than one monolayer on a 0.2-μm-diameter particle. When we eventually deploy the PALMS instrument in the upper troposphere and lower stratosphere, we should be able to detect the presence .
Microstructured Devices for Preparing Controlled Multiple Emulsions

The preparation of multiple emulsions with controlled droplet sizes and internal structures has been a challenge for a long time. However, in recent years, a major breakthrough has been achieved in the preparation of monodisperse single emulsions by small-scale fluid processing, which has enabled the formation of multiple emulsions with the desired droplet sizes, structures, and compositions. This review deals with the preparation of controlled multiple emulsions in various microstructured devices. The four preparation pathways are discussed individually. They are (a) membrane emulsification, (b) microchannel emulsification, (c) the use of a two-dimensional microfluidic device, and (d) the use of a three-dimensional coaxial microcapillary device. The applications of the prepared multiple emulsions to a novel class of materials are also discussed.
Encapsulation, Compensation, and Substitution of Catalyst Particles during Continuous Growth of Carbon Nanotubes

By sequential feeding of catalyst materials, it is revealed that the active growth sites are at the bottom of the carbon nanotubes (CNTs), and that catalyst particles are constantly encapsulated into nanotubes from the bottom. This gives a better insight into the mechanism of CNT formation and on ways to control the growth process. CNTs encapsulated with different materials should enable the study of their electronic or magnetic properties, with potential applications as building blocks for nanoelectronics and as fillers in composites for electromagenetic shielding.
Impact of Microwaves and Water On Acoustical Signatures of Yard And Kitchen Refuse Compost

Acoustical technologies have been used to evaluate characteristics of ecosystems, including soil, demographics and organism behavior. In our research, the acoustics of four states of yard and kitchen refuse compost were analyzed. These included: compost with and without water, and microwaved compost with and without water. The acoustics generated by the microwaved and non-microwaved composts were recorded in a sound chamber. Water was then added to the control and microwaved samples. Subsequently, the acoustics were recorded again. Sonograms were produced for each of the four treatments and the data analyzed in relation to sound Power Spectral Density (PSD). With the addition of water, the nonmicrowaved compost became acoustically active. The PSD was more than five times greater (p < 0.0001, ANOVA repeated measures) than the microwaved compost with and without water and the non-microwaved compost without water. Most of the PSD for all four treatments was in the lower kHz frequency levels (1-4). KHz frequency level one contained the majority of the sound. Compost plus water, had significantly more PSD at kHz level 1 than the sum of kHz levels 2-11. Most of the remaining PSD was found in the lower kHz frequencies. It is concluded that: 1) compost can be considered as a place where organisms are often dormant, and 2) compost can be activated with water used as a pulsing agent.
Preparation of High Oil Absorption Resins by Suspended Emulsion Polymerization and Their Properties

Porous butyl methacrylate/octadecyl acrylate (BMA/OA) copolymers were first synthesized by suspended emulsion polymerization and evaluated for oil absorbency application. Effects of initiator, cross-linking agent, precipitator, dispersant agent, and emulsifier, water/oil ratio on oil absorbency of BMA/OA copolymers were studied in detail. The maximum oil absorbency to toluene was 23.5 g/g.
Free‐volume change in volume phase transition of polyacrylamide gel as studied by positron annihilation: Salt dependence

Variation of free-volume parameters—average radius size, number concentration, and size distribution—of a polyacrylamide (PAAm) gel containing 4 mol % carboxylate anions is studied during a volume phase transition (VPT) caused by a change of sodium chloride (NaCl) concentration. A positron annihilation lifetime technique is used for the determination of the free-volume characteristics. The measurement is performed in an acetone–water 3 : 2 (v/v) [0.27 : 0.73 (mol/mol)] mixed solvent at 20°C, and the free-volume parameters deduced from the analysis of a positron annihilation curve are utilized. An average free-volume size of the swollen PAAm gel, ∼ 0.32 nm in radius, almost agrees with that of the mixed solvent for a corresponding salt concentration, while the size of the collapsed gel, which is ∼ 0.28 nm in radius, is smaller than that of the mixed solvent. The results for the collapsed gel indicate that the hydrogen bond plays a significant role in the nanoscopic environment. The radius of the free-volume of the swollen PAAm gel seems to be influenced by the composition between acetone and water. An inhomogeneity of the nanoscopic structure inside the PAAm gels is discussed in terms of a dispersion of a size distribution of the free-volume. It is concluded that a change of the nanoscopic environment of the PAAm gel during the VPT can be monitored through the free-volume parameters obtained by the positron annihilation lifetime technique. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 2634–2641, 1999
Size and Fluorescence Measurements for Field Detection of Biological Aerosols

This paper describes an instrument developed to monitor the biological fraction of an aerosol. The instrument simultaneously sizes individual particles in a flowing air stream and measures their total fluorescence following excitation at 266 nm. Laboratory data show that these two parameters enable discrimination between individuals of certain bacterial species. Field measurements are presented in which bacterial samples were aerosolized and subsequently detected 800 m downwind.
Determination of thallium at trace levels by electrolyte cathode discharge atomic emission spectrometry with improved sensitivity

An analytical method using electrolyte cathode discharge atomic emission spectrometry (ELCAD-AES) has been described for the trace determination of thallium after improving its sensitivity. Parameters influencing the sensitivity of thallium are investigated at its emission wavelength of 377.572 nm. Maximum enhancement of sensitivity is obtained with the combination of a surfactant (Triton X-114) and potassium iodide. Sensitivity of thallium is improved 12 times with the use of an optimised composition of 3.5% v/v Triton X-114 and 0.2% w/v of KI. Under the optimized conditions, the achieved detection limit is 1 μg L−1 which is 100 times better compared to the detection limit obtained without addition of the surfactant and KI. The precision of the method is 2% for thallium of 500 μg L−1 concentration. The accuracy of the proposed method has been validated by analyzing a NIST 1633b coal fly ash certified reference material and a IAEA 394 coal fly ash material. On comparison, the ELCAD-AES results are found to be in agreement with the certified values and the results obtained by high resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS-GFAAS). The detection limit of thallium for coal fly ash has been found to be 134 ng g−1. Determinations of spiked thallium at trace levels in ground water samples are carried out by ELCAD-AES and HR-CS-AAS and the results are in agreement with each other.
The controlled fabrication of “Tip-On-Tip” TERS probes

Tip-enhanced near-field Raman spectroscopy has exhibited a great ability to detect in situ chemical and structural information on a sample surface with the highest lateral resolution combined with a high sensitivity at the same time. A key challenge in the TERS field is the development and improvement of the fabrication of reproducible metal tip geometries with a sharper apex. In this study, one novel apertureless “Tip-On-Tip” TERS probe with a special plasmonic nanostructure is designed, and a simple Ar+-ion sputtering route has been developed to fabricate silver nanoneedle arrays on the scanning probe microscopy (SPM) cantilevers for tip-enhanced Raman spectroscopy (TERS) probes. These silver nanoneedles possess a very sharp apex with an apex diameter of 15 nm and an apex angle of 20°. The novel TERS probes exhibit enhanced near-field Raman signals compared to an Ag-coated SPM probe, which are attributed to the intense electromagnetic field around the apexes of the Ag nanoneedles and the periodic structure of the Ag nanoneedles.
Elucidation of Mercury Ion Binding Property of a New Aryl Amide Type Podand by Electrochemical and Fluorescence Measurements

Abstract A new aryl amide type podand (AAP), 1,8-bis(o-amidophenoxy)-3,6-dioxaoctane, was synthesized and its mercury ion binding property was elucidated by electrochemical and fluorescence measurements. The effects of supporting electrolyte, pH and scan rate on the electroreduction of AAP and on cyclic voltommogram of mercury ion were investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). It was observed that the complex formation between AAP and mercury ion exhibited pH-dependent behavior in different electrolyte solutions. Elucidation of such properties makes the AAP intriguing candidates as a modifying agent in sensor application for determination of mercury ion in mixture of aqueous solution.
Deep Surface Trap Filling by Photoinduced Carriers and Interparticle Electron Transport Observed in TiO2 Nanocrystalline Film with Time-Resolved Visible and Mid-IR Transient Spectroscopies

TiO2 nanocrystal and TiO2−xSiO2 core/shell films were investigated by band gap excitation followed by detection of the photoinduced carriers with time-resolved transient absorption spectroscopy in both the visible and mid-IR range. The passivation of the TiO2 nanocrystal with the SiO2 shell has two goals, that is, reducing the surface-trapped states and segregating the TiO2 nanoparticles in the sintered film to prevent interparticle carrier migration. The results show that within the accessible mid-IR range (5−6.5 μm) the observed transient absorptions of the TiO2 crystal and TiO2−xSiO2 core/shell films exhibit an IR spectrum typical of intraband transition of free electrons where the observed absorption intensity is proportional to λp (λ = wavelength/μm), and p was determined as 2.6 for the TiO2 nanoparticle film and 4.9 for the TiO2−xSiO2 core/shell composite film, respectively. Three typical kinetic phases for the transient IR absorption decay profile of the TiO2 film have been observed, that is, a rap.
Using dispersion decreasing fiber to generate pulse delay and compensate the pulse distortion

Dispersion effect in stimulated Brillouin scattering (SBS) slow light is studied to compensate the pulse distortion using SBS - dispersion decreasing fiber (SBS-DDF). SBS-DDF has the feature of the dispersion increasing and effective area decreasing, hence intensity increasing along the fiber. This increased intensity is used to balance the intensity decreasing of the pump beam from pump and probe interaction in Brillouin medium at the Brillouin frequency and fiber attenuation. The same principle is applied to the counter propagating Stokes wave, that decreased intensity due to the effective core area increasing is used to eliminate Stokes beam saturation through Brillouin loss interaction. A minimum pulse distortion with high delay of 1.8ns over 2ns pulse is achieved.
Nanoseashells and Nanooctahedra of MoS2: Routes to Inorganic Fullerenes

Nanooctahedra of MoS2 are considered to be the true inorganic fullerenes, exhibiting different properties from the bulk and also other closed-cage morphologies of the same material. These structures are produced in high energy systems where the synthesis is performed far from equilibrium conditions, and the reaction mechanism involved remains unknown. Here, the discovery of two imperfect structures of nanooctahedra-the distorted octahedra and seashell structures with meander-like cross sections-is reported and studied in detail using transmission electron microscopy and quantum-mechanical methods. These nanoparticles can serve to understand the synthesis route by establishing the basic principles of their morphology and stability. The fundamental properties of the inorganic lattice are the basis for matching the projections observed in microscopy images with a suggested atomistic model, Quantum-mechanical calculations are used to estimate their stability and electronic properties. It was concluded that the production of nanooctahedra involves a high temperature stage, where lattice defects enable the formation of a closed structure Without a templating particle. Thereafter at lower temperatures, the mixture of products is carried forward and the annealing contributes to the enrichment of the product with more symmetric structures.
Analytic approximations for degenerate accumulation layers in semiconductors, with applications to barrier lowering in isotype heterojunctions

The Joyce‐Dixon approximation for the Fermi energy in a degenerate semiconductor is used to obtain rapidly converging series expansions for both the potential and the electric field for degenerate accumulation layers in semiconductors, as functions of the electron concentration. The expressions are valid for electron concentrations up to about 20 times the effective density of states. The approximation is applied to Schottky barriers on degenerate semiconductors, where it leads to an increase in the value of the Gummel‐Scharfetter correction in the C‐V relation for Schottky barriers. A detailed quantitative treatment is given for the barrier lowering in abrupt n‐N heterojunctions with increased reverse bias. Both barrier lowering and reverse bias are given as closed‐form parametric expressions, with the electron concentration at the bottom of the heterojunction notch as the independent variable.
DNA Biosensor Investigations in Fish Bile for Use as a Biomonitoring Tool

Abstract Polycyclic aromatic hydrocarbons (PAH) are responsible for a number of adverse effects on aquatic biota due to their persistence and potential for accumulation. The recognition and quantification of biliary PAH metabolites from exposed fish represents a valuable tool in the evaluation of warning signals indicative of exposure. In this work, an electrochemical DNA biosensor is proposed as a screening device for the rapid detection of PAH metabolites in fish bile samples. Preliminary studies were performed using the 3-hydroxy-benzo(a)pyrene as a model compound. The effect of the 3-hydroxy-benzo(a)pyrene on the surface-confined DNA was found to be linearly related to the concentration of the PAH derivative in solution. Then, the DNA biosensor was used to investigate the presence of PAH metabolites in fish bile samples. The sensor was able to clearly distinguish PAH-exposed fish bile samples from unexposed control samples. A total analysis time of 7 min was established (including electrode surface pre-treatment, dsDNA immobilization and interaction steps) and only 10 μL of diluted sample solution were needed. DNA biosensors are cost effective and sensitive; moreover, the coupling of a portable and battery-operating potentiostat with disposable carbon strips meets the requirements for in situ measurements.
The crystal structure of Sr-hardystonite, Sr2ZnSi2O7

Abstract A synthetic strontium isomorph (Sr2ZnSi2O7) of the hardystonite structure (Ca2ZnSi2O7) was investigated with X-ray powder diffraction. The average structure (S.G. P-421m), a = 8.0007(1) Å, c = 5.1722(1) Å, was refined by Rietveld method and a RF2 = 0.0216 was achieved using 394 independent reflections. The results show that Sr-hardystonite has a melilite-type structure with no incommensurate modulations. Its geometrical and bonding features are consistent with trends defined by the other so-called normal and modulated melilite structures.
Conducting IPN based on polyaniline and crosslinked cellulose

Polyaniline/crosslinked cellulose conductive interpenetrating polymer networks (IPNs) were prepared by oxidative polymerization of aniline within the self-synthesized cellulose network using ammonium persulphate as oxidant. The conductivity of the IPN increases and then decreases with decrease in the aniline/(NH 4 ) 2 S 2 O 8 ratio, with increase in the HCl/aniline ratio, with increase in aniline content, as well as with increase in reaction time. In addition, the conductivity of the films strongly depends on the amount of tetraethyl orthosilicate crosslinker. In comparison with polyaniline/cellulose acetate composites, the conductivity increases by an order of one to two magnitudes in spite of the lower polyaniline content in this work.
Improvements in the visual evaluation of soil structure

Spade methods to visually evaluate soil structural quality (Sq) are simple, quick, cheap and can be used by farmers, gardeners, consultants and the scientific community. However, European and Brazilian users of one such method, viz. visual evaluation of soil structure (VESS) which is a development of the Peerlkamp test, have been concerned about its subjectivity. The method of soil slice break‐up and operator influence on scores have been questioned. Thus, our aim was to make soil scoring by the VESS technique more objective and thus to revise the scoring guide. We compared scoring with normal breaking up of the soil slice by hand with scoring after breaking up the slice by dropping (drop shatter) to make the soil break‐up more operator independent. After slice break‐up, aggregates were split by hand and their internal porosity was evaluated to develop the use of visible porosity as an aid to scoring. This proved inconclusive on its own, so a method of reducing larger aggregates to 1.5–2.0 cm core fragments and describing their shape and porosity was developed to score soil Sq. Breaking up a spadeful of soil by hand or by dropping resulted in the same Sq score. The method of reducing aggregates and evaluation of their shape improved VESS, particularly in the middle range of soil quality and the revised chart is shown. VESS was sensitive to changes in Sq in layers within the profile and its use for diagnosing Sq in different layers allows targeted soil improvement by tillage.
RELATIONSHIP OF USDA MARBLING GROUPS TO PALATABILITY OF COOKED BEEF

As marbling increased from“practically devoid” to“moderately abundant”, loin steaks were more palatable (P<0.05) about 2/3 of the time, round steaks were more palatable (P<0.05) about 1/8 of the time, and loin steaks were more likely to be assigned high (≥6.00) panel ratings and to have low (≤3.63 kg) shear values. However, increases in marbling from“slight” to“moderately abundant” (A maturity) and from“small” to“moderately abundant” (A+B maturity) had little or no efect on percentage incidence of loin or round steaks with panel ratings ≤2.99 or ≥4.00, or with shear values ≥6.35 kg or ≤4.99 kg. Differences in marbling explained about 33% (loin) and 7% (top round) of the variation in overall palatability ratings in A, B, C, and A+B maturity carcasses.