Miracle-dz/UniFAR-FTUs huggingface dataset:
Single particle ICP-MS combined with a data evaluation tool as a routine technique for the analysis of nanoparticles in complex matrices

Detection and characterization of nanoparticles (NPs) in complex media as consumer products, food and toxicological test media is an essential part of understanding the potential benefits and risks of the application of nanoparticles. Single particle ICP-MS (spICP-MS) was studied as a screening tool for the detection and characterization of nanoparticles in complex matrices such as food and biological tissues. A data evaluation tool was created for the calculation of particle size, concentration and size distribution from the raw data. spICP-MS measurements were carried out on a standard quadrupole instrument as well as on a sector-field instrument. Performance characteristics were determined for four types of NPs. For the quadrupole instrument the size detection limits were 20 nm (Au and Ag), 50 (TiO2) and 200 nm (SiO2). For the sector-field instrument size detection limits are lower, 10 nm (Au). Concentration detection limits ranged from 1 ng L−1 for 60 nm Au NPs to 0.1 μg L−1 for 500 nm SiO2 particles. The dynamic range of spICP-MS is limited to two orders of magnitude and as a consequence sample dilution is often required. The precision of the method was found to be <5% and <10% for the determination of particle size and concentration, respectively while the accuracy for particle size (Au NP only) was <10%. The robustness against potential sample matrix components was investigated. The applicability to routine samples was demonstrated by four examples (food, waste water, culture media and biological tissues). The presented combination of spICP-MS measurements with a powerful data evaluation tool enables the use of this technique as a fast, cost efficient and easy to use screening tool for metal and metal oxide NPs that can be widely implemented in the statutory monitoring of food and consumer products for the presence of NPs, as well as in the analytical evaluation of toxicological studies.
Effect of K2SO4 concentration on extractability and isotope signature (δ13C and δ15N) of soil C and N fractions

Determination of the labile soil carbon (C) and nitrogen (N) fractions and measurement of their isotopic signatures (δ13C and δ15N) has been used widely for characterizing soil C and N transformations. However, methodological questions and comparison of results of different authors have not been fully solved. We studied concentrations and δ13C and δ15N of salt‐extractable organic carbon (SEOC), inorganic (N–NH4+ and N–NO3−) and organic nitrogen (SEON) and salt‐extractable microbial C (SEMC) and N (SEMN) in 0.05 and 0.5 m K2SO4 extracts from a range of soils in Russia. Despite differences in acidity, organic matter and N content and C and N availability in the studied soils, we found consistent patterns of effects of K2SO4 concentration on C and N extractability. Organic C and N were extracted 1.6–5.5 times more effectively with 0.5 m K2SO4 than with 0.05 m K2SO4. Extra SEOC extractability with greater K2SO4 concentrations did not depend on soil properties within a wide range of pH and organic matter concentrations, but the effect was more pronounced in the most acidic and organic‐rich mountain Umbrisols. Extractable microbial C was not affected by K2SO4 concentrations, while SEMN was greater when extracted with 0.5 m K2SO4. We demonstrate that the δ13C and δ15N values of extractable non‐microbial and microbial C and N are not affected by K2SO4 concentrations, but use of a small concentration of extract (0.05 m K2SO4) gives more consistent isotopic results than a larger concentration (0.5 m).
A novel thermal management system for electric vehicle batteries using phase-change material

A novel thermal-management system that incorporates phase-change material (PCM) is proposed and investigated for electric vehicle (EV) applications. A commercial finite-element (FE) software, PDEase2D, was used to simulate the thermal behavior of EV battery modules with a PCM thermal management system. Simulation results show that the temperature profile of the cells integrated in the module design was substantially more uniform during discharge at different rates than without PCM. The PCM system is effective in thermally sensitive batteries such as Li-ion and most Li-polymer batteries with a significant reversible heat effect. The heat generated during discharge and stored as latent heat is then largely utilized during charge, and a smaller part of it is transferred to the surroundings. The stored heat will be rejected to the module when the battery is left to relax or when its temperature drops below the melting point of the PCM. This is an important advantage for EV operation under cold conditions or in space applications where the battery temperature drops significantly when an orbiting satellite moves from the light to the dark side of the earth.
Novel SH-SAW gas sensor based on graphene

In this article, a novel gas sensor platform has been studied. Several layers of graphene have been deposited on a SH-SAW, as a sensitive layer. Innovative methods of graphene solutions have been prepared in order to explore gas sensing applications. The real time detection measurement of the coated sensor under ethanol and humidity is presented. The adsorption of vapors leads to a frequency shift of 10.5 kHz and 22.7 kHz, at exposure of 100 ppm of ethanol and 6.22% of Relative Humidity, respectively. The experiments have been realized at room temperature; rapid response and recovery time were observed.
A Parametric Study on the Bixin Oil Suspensions Produced Using Annatto Seeds (Bixia Orella) and Its Potential Application in Coloring Margarine Products

Bixin obtained from Annatto seeds (Bixinella orella), has been used by the food industry as a source for natural color for a long time due to its low toxicity and high colorific value. Given its potential applications in dairy and meat industry to obtain a desired reddish orange hue, a method was sought, which would quickly extract the desired pigment from the seed coat at low cost and allow for its direct application in the desired product. The bixin mass was extracted using demineralized water (D.M.W), sunflower oil or methanol and was then resuspended in sunflower oil to a bixin strength of 10%. A study of the extraction process, viscosity and color hue (L*a*b value) of the 10% formulated product in margarine at low doses of 0.1% was carried out. Data indicated that methanol extraction provided the desirable reddish hue in margarine and yielded a product with lowest viscosity.
Prediction of Ethene+Oct-1-ene Copolymerization Ideal Conditions Using Artificial Neuron Networks

The most influential parameters on polymerization of ethene + oct-1-ene using a metallocene catalyst system are temperature, ethene pressure, and the amount of hydrogen used for polymerization. An implemented artificial neural network (ANN) is a supervised back-propagation model with different architectures. An ANN for determining the conditions in the copolymerization of ethene + oct-1-ene using a metallocene catalyst system to produce a copolymer with specific chains has been implemented. It has been shown that the proper functioning of the ANN is implemented with satisfactory R values. Therefore, it is concluded that the ANN developed is an effective tool to determine the conditions of copolymerization of ethene and oct-1-ene.
Primary structure and solution conditions determine conformational ensemble properties of intrinsically disordered proteins

xvi 1 Intrinsically disordered proteins (IDPs) have distinctive sequence characteristics and exhibit an ensemble of conformations . 1 1.1 The importance of sequence-ensemble relationships . 5 1.2 Limiting models from polymer physics as descriptors of conformational heterogeneity . 8 1.3 Toward more realistic polymer models for IDPs . 11 1.4 Aqueous solutions are poor solvents for generic polypeptide backbones 15 1.5 Polar tracts form compact globules in aqueous solutions . 17 1.6 IDPs with charged residues constitute a distinct archetype from polar tracts . 18 1.7 References . 19 2 Net charge per residue modulates conformational ensembles of intrinsically disordered proteins . 30 2.
Ammonolytical conversion of microcrystalline gallium antimonide GaSb to nanocrystalline gallium nitride GaN: thermodynamics vs. topochemistry

Reaction of microcrystalline powders of readily available gallium antimonide GaSb with ammonia gas at elevated temperatures afforded in one step high yields of nanocrystalline powders of the semiconductor, gallium nitride GaN. In particular, temperatures of 900–1000 °C and suitable reaction times of 36–170 hours resulted in complete nitridation in the system. GaN was prepared as a mixture of the major stable hexagonal and the minor metastable cubic polytypes. Formation of the cubic GaN was consistent with topochemistry playing a meaningful role in the ammonolysis of the cubic GaSb substrate. Specific experimental conditions, including variations in the reaction temperature/time and manual grinding or high energy ball milling of the substrate, had a significant impact on the final GaN polytype make-up and average crystallite size, the latter ranging from a few to a few tens of nanometers. Under the applied conditions, all by-products were conveniently removed from the reaction mixture as volatile species, thus affording chemically pure GaN nanopowders of very good quality.
The composition and concentration of n‐alkanes in retail samples of edible oils

Abstract: A range of edible oils were purchased from a variety of retail outlets and analysed for their n-alkane (Σ33/15) content. The concentrations ranged from 7 to 166 mg kg−1, the lowest being walnut oil and the highest sunflower oil. n-Alkanes with chain lengths of C27, C29 and C31 predominated in all of the plant oils except olive oil where C23, C25 and C27 were the most significant. The results of this pilot survey suggest that the n-alkanes are indigenous and that their composition may be useful in characterising a specific plant seed oil. Two of the 42 samples analysed showed markedly different alkane patterns in which profiles similar to petroleum-based sources dominated the contribution from odd carbon n-alkanes typical of seed oils.
Pyrochemical neutron multiplicity counter design

Pyrochemical process materials are difficult to measure using conventional neutron counting methods because of significant self- multiplication and variable ({alpha},n) reaction rates. Multiplicity counters measure the first three moments of the neutron multiplicity distribution and thus make it possible to determine sample mass even when multiplication and ({alpha},n) rate are unknown. A new multiplicity counter suitable for inplant measurement of pyrochemical process materials has been designed using Monte Carlo simulations. The goals were to produce a counter that has high neutron detection efficiency, low die-away time, a flat spatial efficiency profile, and is insensitive to the neutron energy spectrum. Monte Carlo calculations were performed for several prototype models consisting of four rings of 71-cm active length {sup 3}He tubes in a polyethylene body. The cadmium-lined sample well is 25 cm in diameter to accommodate a wide variety of inplant sample containers. The counter can be free-standing or in-line without mechanical modification. The calculations were performed to determine the above design criteria for several configurations of tube spacing, cadmium liners, and sample height. Calculations were also performed for distributed sample sources to understand the integrated effects of variable neutron spectra on the counter. 5 refs., 8 figs., 1 tab.
Conformational changes in twitchin kinase in vivo revealed by FRET imaging of freely moving C. elegans

The force-induced unfolding and refolding of proteins is speculated to be a key mechanism in the sensing and transduction of mechanical signals in the living cell. Yet, little evidence has been gathered for its existence in vivo. Prominently, stretch-induced unfolding is postulated to be the activation mechanism of the twitchin/titin family of autoinhibited sarcomeric kinases linked to the mechanical stress response of muscle. To test the occurrence of mechanical kinase activation in living working muscle, we generated transgenic C. elegans expressing twitchin containing FRET moieties flanking the kinase domain and developed a quantitative technique for extracting FRET signals in freely moving C. elegans, using tracking and simultaneous imaging of animals in three channels (donor fluorescence, acceptor fluorescence, and transmitted light). Computer vision algorithms were used to extract fluorescence signals and muscle contraction states in each frame, in order to obtain fluorescence and body curvature measurements with spatial and temporal precision in vivo. The data revealed statistically significant periodic changes in FRET signals during muscle activity, consistent with a periodic change in the conformation of twitchin kinase. We conclude that stretch-unfolding of twitchin kinase occurs in the active muscle, whereby mechanical activity titrates the signalling pathway of this cytoskeletal kinase. We anticipate that the methods we have developed here could be applied to obtaining in vivo evidence for force-induced conformational changes or elastic behavior of other proteins not only in C. elegans but in other animals in which there is optical transparency (e.g zebrafish).
Single Scattering Albedo Monitor for Airborne Particulates

We describe a robust, compact, field deployable instrument (the CAPS PMssa) that simultaneously measures airborne particle light extinction and scattering coefficients and thus the single scattering albedo (SSA) on the same sample volume. With an appropriate change in mirrors and light source, measurements have been made at wavelengths ranging from 450 to 780 nm. The extinction measurement is based on cavity attenuated phase shift (CAPS) techniques as employed in the CAPS PMex particle extinction monitor; scattering is measured using integrating nephelometry by incorporating a Lambertian integrating sphere within the sample cell. The scattering measurement is calibrated using the extinction measurement. Measurements using ammonium sulfate particles of various sizes indicate that the response of the scattering channel with respect to measured extinction is linear to within 1% up to 1000 Mm−1 and can be extended further (4000 Mm−1) with additional corrections. The precision in both measurement channels is less than 1 Mm−1 (1s, 1σ). The truncation effect in the scattering channel, caused by light lost at extreme forward/backward scattering angles, was measured as a function of particle size using monodisperse polystyrene latex particles (n = 1.59). The results were successfully fit using a simple geometric model allowing for reasonable extrapolation to a given wavelength, particle index of refraction, and particle size distribution, assuming spherical particles. For sub-micron sized particles, the truncation corrections are comparable to those reported for commercial nephelometers. Measurements of the optical properties of ambient aerosol indicate that the values of the SSA of these particles measured with this instrument (0.91 ± 0.03) using scattering and extinction agreed within experimental uncertainty with those determined using extinction measured by this instrument and absorption measured using a multi-angle absorption photometer (0.89 ± 0.03) where the uncertainties are derived from best estimates of the accuracy of the two approaches. Copyright 2015 American Association for Aerosol Research
A comprehensive approach based on SVM to model pitting corrosion behaviour of EN 1.4404 stainless steel

Potentiodynamic polarisation tests have been widely used to evaluate pitting corrosion behaviour of stainless steels. This technique involves two principal steps: the interpretation of the polarisation curve and the microscopic analysis of the material surface. Therefore, analysing the influence of all possible environmental conditions on pitting corrosion behaviour can be complex. To deal with this problem, automatic models based on Bayes classifier (BC) and support vector machines (SVMs) techniques are presented in this work. The principal environmental variables involved in pitting corrosion: chloride ion concentration, pH and temperature are considered. Based on the obtained results related to precision and accuracy terms, SVMs models using linear or radial basis function kernels outperform models based on Bayes theory. In addition, ROC analysis reveals that SVMs models using linear kernel is the best option providing maximum values of sensitivity and specificity. These results reflect the validity of the presented model to be applied in the automatic determination of the corrosion state of austenitic stainless steel as function of environmental conditions, not requiring the use of polarisation tests.
Assessment of Two Electro-Rheological Fluids for Use in Recoil Abatement Applications

Abstract : The electrical and rheological properties of two state-of-the-art electro-rheological (ER) fluids have been evaluated from 0 to 60 deg C, using a unique constant-stress viscometer. The measurements were performed at the facilities of ER Fluid Developments, Ltd. (ERFD), a small British company located in Sheffield, United Kingdom, that specializes in developing and marketing ER fluid-based technology. In addition to these measurements, the response time of the fluids was determined using another instrument located at the nearby University of Sheffield. The constant-stress viscometer, or dynamic rig, developed and owned by ERFD, permits the yield stress, plastic viscosity, and direct current (DC) current density of an ER fluid to be determined as a function of electric field and temperature. The yield stress, plastic viscosity, current density, and response time of each fluid were found to strongly depend on temperature. The first fluid appears to be stronger (i.e., has a higher yield stress), with lower current densities at lower temperatures up to 40 deg C. In that temperature range, the second fluid is somewhat weaker, susceptible to electrical breakdown at or above 2.0 kV/mm, and generally draws more current At higher temperatures, however, the current density of the first fluid dramatically increases to exceed the desired level of 10 mu-A/sq cm. The corresponding current density increase of the second fluid is significantly smaller. In light of the differences between the measured properties, the results and their implications associated with the intended use of the fluids are discussed. A general description of ER fluid behavior, as well as the theories of operation of the instruments, are also described.
NiO nanosheets as efficient top hole transporters for carbon counter electrode based perovskite solar cells

Herein, we present fully printable carbon electrode based perovskite solar cells using highly crystalline NiO nanosheets as top hole transport layers, mesoporous TiO2 nanoparticles as a bottom electron transport layer and ZrO2 as an intermediate spacer layer, respectively. Time-resolved photoluminescence decay measurements, electron impedance spectroscopy and transient photovoltage decay measurements have revealed that the NiO nanosheets as top hole transporters exhibit superior charge collection efficiency and a prolonged charge lifetime. As a result, an impressive power conversion efficiency of 14.2% is achieved under standard testing conditions.
Trace gas chemistry in a young biomass burning plume over Namibia: Observations and model simulations

[1] We investigated trace gas emissions from a biomass fire near Otavi, northern Namibia, on 13 September 2000 as part of the Southern African Regional Science Initiative 2000 (SAFARI 2000). Observations included fast measurements of carbon monoxide (CO), ozone (O3), acetone (propanone, CH3COCH3), and acetonitrile (ethanenitrile or methyl cyanide, CH3CN). Additionally, flask samples were taken and analyzed for nonmethane hydrocarbons (NMHCs). Measurements close to the fire were used to quantify the emissions of the different compounds. Several transects were flown through the plume downwind to study the chemical changes in the plume during the first 2 hours after the emission. Fast production of O3 was observed, with the O3/CO molar enhancement ratio ER(O3/CO) reaching ∼0.10 in the plume after 2 hours. Acetone molar enhancement ratios (ER(acetone/CO) were ∼5 × 10−3 in the very young plume but ∼9 × 10−3 after 1–2 hours of aging, pointing to a substantial fast secondary acetone formation. To understand the chemical processes occurring in the plume, we simulated the plume chemistry with a dilution box model. The fast O3 production is well reproduced, whereas acetone mixing ratios in the aging plume are underestimated by the model. This points to additional yet unidentified acetone precursors. The model suggests an overall molar enhancement ratio of these compounds with respect to CO of 7.5 × 10−3 and a reaction rate coefficient of 6 × 10−11 cm3 s−1 for the reaction with HO radicals. The secondary acetone production may cause the net acetone source from biomass burning to be underestimated when only data from observations immediately near the fires are considered. The atmospheric implications of these findings are discussed.
Development and validation of a HPTLC method for simultaneous estimation of Atorvastatin calcium and Losartan Potassium in combined dosage form

A simple, precise, rapid and accurate HPTLC method has been developed for the simultaneous estimation of Atorvastatin calcium (ATO) and Losartan Potassium (LOS) in bulk and pharmaceutical dosage form. Precoated silica gel 60 F254 plate was used as stationary phase. The separation was carried out using Toulene: Methanol (8:2 v/v) as mobile phase. The densitometric scanning was carried out at 260 nm. The Rf values was found to be 0.15 ± 0.01 for ATO and 0.09 ± 0.01 for LOS. The linearity was obtained in the range 200-1200 and 500-3000 ng/band ng/band with correlation coefficients (r 2 = 0.9994) and (r 2 = 0.9999) for ATO and LOS. The method was validated for specificity, linearity, accuracy, precision, LOD, LOQ and robustness. The percentage recovery obtained for ATO and LOS were in the range of 99.25-101.5 % and 100.75-101.26 %, respectively. The proposed method was optimized and validated as per the ICH guidelines. Keywords: Atorvastatin calcium, Losartan Potassium, HPTLC, Method Validation.
Isolation of nonvolatile, organic solutes from natural waters by zeotrophic distillation of water from N,N-dimethylformamide

Nonvolatile, organic solutes that comprise the dissolved organic carbon (DOC) in saline waters were isolated by removal of the water by distillation from a N,N-dimethylformamide-formic acid-acetonitrile mixture. Salts isolated with the DOC were removed by crystallization of sodium chloride and sodium sulfate from the solvent mixture, removal of silicic acid by acidification and precipitation, removal of boric acid by methylation and volatilization, and removal of phosphate by zinc acetate precipitation. Chemical alteration of the organic solutes was minimized during evaporative concentration steps by careful control of acid concentrations in the solvent mixture and was minimized during drying by conversion of the samples to pyridinium and sodium salts. Recoveries of various hydrophilic organic standards from aqueous salt solutions and recoveries of natural organic solutes from various water samples varied from 60 to 100%. Losses of organic solutes during the isolation procedure were nonselective and related to the number of salt- and precipitate-washing cycles in the procedure.