Miracle-dz/UniFAR-FTUs huggingface dataset:
Particle–Focusing Characteristics of Matched Aerodynamic Lenses

Forming collimated and size–selected particle beams is a necessary component of certain instruments and industrial processes. An ideal aerosol inlet produces particle beams at high efficiency and transmission rate. The particle transmission rate can be maximized by slot geometries to generate a tightly focused particle beam that is confined to a desired volume. Traditionally, orifices and capillaries have been employed to generate focused particle beams where particle inertia is used to separate them from the carrier gas. The goal of this work is to improve the current inlet geometries for enhanced transmission of particles. For this purpose, we propose a novel inlet geometry that comprises a series of matched capped slots upstream of a choked orifice inlet. By adjusting the pressure, the geometry transmits an arbitrary particle size with high efficiency while maintaining a high flow rate. The slot dimensions can be analytically determined by constraining the design such that the slots and choked orifice focus the same particle sizes and have the same mass flow rate. Numerical simulations of the flow and particle trajectories through the inlet are carried out using the CFD code FLUENT. The new geometry is found to enhance the focusing characteristics of the orifice while maintaining the high flow throughput. The geometry is further optimized to maximize the transmission rate.
Heart rate variability training and control of emotions

This thesis outlines an investigation into the effects of heart rate variability training (HRVT) on stress and performance, and participants’ experiences of undertaking HRVT. Data were collected from male Middle-Eastern adolescent student-athletes. Study 1 examined the acute effects of a single 20-minute HRVT session on performance under pressure. Thirty-six participants completed a reactive stress tolerance test after both HRVT and a control condition (group discussion about pre-competition routines). Completing HRVT did not improve performance. Study 2 built on Study 1 by exploring the effects of a 5-week HRVT protocol consisting of five lab-based and five home-based 20-minute HRVT sessions on biomarkers of the stress response. Fifty-seven participants were randomly assigned to an experimental (n=30) and a control (n=27) group, comprising five educational sessions. There were acute effects of HRVT on a-amylase levels within each session, with a-amylase levels decreasing over the course of the session. Both cortisol and a-amylase levels reduced over the course of the 5-week HRVT protocol. There were significantly lower cortisol levels and skin conductance levels in the experimental compared to the control group at the end of the training programme. Study 3 focused on the reflections of 22 participants who took part in the HRVT programme in Study 2. Participants proposed that apart from the identification of the individualized resonant breathing frequency, the customization of the inhalation-exhalation ratio is highly related to the participants’ experience. That change to the HRVT programme may further enhance effectiveness, and, that effectiveness can be increased by practicing it regularly and including it as part of a pre-competition routine.
Laboratory set-up for X-ray diffraction at high pressures

We describe here a simple set-up for X-ray diffraction under high pressure using a diamond anvil cell employing a sealed tube. The set-up works in angular dispersive geometry and is built using rather common components that are available in a research laboratory. We show that using this set-up one can routinely acquire good-quality data for the determination of structural properties under pressure and the equations of state. Technical details are presented along with examples of experimental results for sodium chloride and LiV2O4.
pH‐dependent extraction of soil and soil amendments to understand the factors controlling element mobility

A combination of the pH‐dependent leaching test CEN/TS 14429 and geochemical modelling (LeachXS©‐ORCHESTRA) was used to evaluate the partitioning of major, minor and trace elements in relation to their phosphorus retention capability, the release of non‐nutrient constituents, their reduction of soil acidity and their organic matter retention. One Australian soil sample and two different soil amendments (Red Lime and Alkaloam) were studied. The pH‐dependent leaching test showed that the acid neutralization capacity and the phosphorus retention of the soil were improved, respectively, by a factor of two to five and by a factor of two to ten after addition of these amendments. The amendments improved retention of dissolved organic matter (by a factor of 3–10) and did not increase leachability of undesired contaminants. The partitioning as obtained from modelling between free and dissolved organic‐carbon‐bound metals provides insight into the potential for uptake (bioavailability). This partitioning is very pH‐dependent and therefore testing and associated chemical speciation modelling provide valuable information for judging traditional soil improvers and soil amendments, including the waste‐derived soil amendments Alkaloam and Red Lime.
Alkyl chain motions in columnar mesophases: a quasielastic neutron scattering study of dicopper tetrapalmitate

The dynamical behaviour of the alkyl chains in dicopper tetrapalmitate is investigated in the columnar liquid crystal phase, using incoherent quasielastic neutron scattering by several selectively deuterated derivatives. A mathematical model is developed for the evaluation of the scattering function which yields the free volume accessible to each hydrogen atom along the chains, approximated by a sphere. It is shown that the hydrogen atoms linked to the carbons close to the core undergo very little motion. The radius of the spheres is a nearly linear function of the distance from the core between the first and the fifth carbons and then reaches a limiting value directly related to the spacing between the stacked molecules. These results were fully confirmed by the analysis of the overall quasielastic broadening of the spectra as a function of the momentum transfer.
Preservation of Microstructure in Peach and Mango during High-pressure-shift Freezing

A histological technique was used to evaluate modifications on the microstructure of peach and mango due to classical methods of freezing and those produced by high-pressure-shift freezing (HPSF). With the high-pressure-shift method, samples are cooled under pressure (200 MPa) to -20°C without ice formation, then pres- sure is released to atmospheric pressure (0.1 MPa). The high level of supercooling (approximately 20°C) leads to uniform and rapid ice nucleation throughout the volume of the specimen. This method maintained the original tissue structure to a great extent. Since problems associated with thermal gradients are minimized, high-pressure-shift pansion when the unfrozen inner part of the product undergoes phase transition. When the stress generated in the interior of the product exceeds the resistance of the frozen material at the surface, freeze-cracking takes place. With high-pressure-shift freezing (HPSF), this problem may be avoided since the initial formation of ice is instantaneous and homogenous throughout the volume of the product, thus eliminating internal stresses. High pressures can be applied during freezing of foods in dif- ferent ways: Phase transition can occur either under constant pressure (pressure-assisted freezing to obtain ice I or other types of ice: ice II, ice III, and so on) or due to a pressure change (pressure-shift freezing) as Knorr and others (1998) pointed out. Two types of high-pressure-shift freezing can be distinguished: one in which expansion occurs gradually (always near the equi- librium curve), and the other in which expansion to atmospher- ic pressure occurs suddenly, thus achieving considerable super- cooling at atmospheric pressure. Fuchigami and others (1997a, 1997b) conducted pressure-assisted freezing experiments to ob- tain several ices different from ice I, and high-pressure-shift freezing experiments with gradual expansion (lasting 1 min from 200 MPa to atmospheric pressure) in carrots. They found that the less harmful freezing methods, for vegetable structure, were pressure-assisted freezing inducing formation of ice III, with smaller specific volume than liquid water, and gradual high-pressure shift freezing. However, these authors did not use high-pressure-shift freezing with abrupt expansions. The objective of the present work was to analyze the effect of freezing on the microstructure of 2 whole fruits of large size— peach and mango —by comparing traditional methods and high-pressure-shift freezing with abrupt expansions.
Impacts of clearcut harvesting and wildfire on soil nutrient status in the Quebec boreal forest

Wildfire has historically been the major cause of stand initiation in the boreal forest, shaping species diversity, successional and ecosystem processes. Clearcut harvesting may differ from fire in its effects on soil and vegetation processes and thus may cause long-term changes in stand productivity or biodiversity. This study compared the soil properties of mesic black spruce (Picea mariana) stands burned 2, 14, 21 yr prior to sampling, with stands clearcut within ±3 yr of each wildfire and recently undisturbed control stands. The forest floor (FH) and mineral soil (0-10 cm) were sampled volumetrically, air dried and analysed for pH, organic carbon content, available P, Ca, Mg, and K, mineralizable N and nitrification. Forest floors were also digested and analysed for total N, P, K, Ca and Mg. Significant differences between disturbed and control stands were observed in all study areas, with disturbance effects generally decreasing with time since disturbance. Burned stands generally had forest floors w.
Estimation of pKa Using Semiempirical Molecular Orbital Methods. Part 1: Application to Phenols and Carboxylic Acids.

The electronic properties of small molecules can be calculated quickly and with a reasonable degree of accuracy using semiempirical QM methods. In this study a set of QM properties derived from frontier electron theory have been used to produce a predictive model of the dissociation constants of phenols, benzoic acids and aliphatic carboxylic acids. The pK a values and structures of nearly 500 compounds were extracted from the Physprop database for this purpose. Multiple linear regression was used to search for relationships between pK a and the calculated QM properties. In most cases only a single independent variable, electrophilic superdelocalisability, was needed to produce a good model of pK a . The advantages of our approach are in the speed of calculation and the simplicity of the resultant models. The merits of using semiempirical methods to predict pK a are discussed in relation to previous studies.
Rapid Gas Sensor Measurements To Determine Spoilage of Capelin (Mallotus villosus)

Changes in volatile compounds of capelin were monitored by gas sensor measurements, sensory evaluation, and TVB analysis. Capelin was stored at 5 and 0 °C for 8 days, and the effect of 0.2% added acetic acid was studied at 5 °C. An instrument with electrochemical gas sensors was developed to monitor the volatile compounds of capelin during spoilage such as alcohols, amines, and sulfur compounds. The results of the gas sensor measurements showed good reproducibility, and the responses of selected sensors correlated well with classical TVB measurements. GC analysis of sulfur compounds was done simultaneously to identify and determine the relative abundance of these compounds in the headspace of capelin during storage, and a descriptive sensory evaluation scheme was developed.
Rotation of methyl side groups in polymers: A Fourier transform approach to quasielastic neutron scattering. 1: Homopolymers

The rotational motion of the ester methyl group in poly(methyl methacrylate) (PMMA) was investigated using quasielastic neutron scattering (QENS). A comparison between the authors results and the QENS data reported in the literature for PMMA-d{sub 5} indicates that the amount of quasielastic broadening is highly dependent upon the energy resolution of the spectrometer. This anomalous behavior is here attributed to the method of analysis, namely, the use of a single rotational frequency. Such a procedure leads to a non-Arrhenius temperature dependence, to a temperature-dependent elastic incoherent structure factor, and to values of rotational frequency which are resolution dependent. They propose an alternative approach to the analysis of the QENS data which accounts for the existence of a distribution of rotational frequencies. The frequency data are Fourier transformed to the time domain, and the intermediate scattering function is fitted using a stretched exponential or Kohlraush-Williams-Watts function. The excellent overlap between data from different spectrometers leaves no doubt on the adequacy of their procedure. Measurements of the ether methyl group rotation in poly(vinyl methyl ether) (PVME) are also reported. The PVME data confirm that the behavior observed for PMMA-d{sub 5} is likely to be a common feature to all polymeric systems.
Distribution of iron and sulfur and their speciation in relation to degradation processes in wood from the Swedish warship Vasa

Wood samples from the Swedish warship Vasa were analysed by scanning electron microscopy and X-ray absorption spectroscopy with the focus on speciation and distribution of iron and sulfur compounds in the wood matrix. Both these elements were found at high concentration (10–100 mg g−1) in the surface region as a result of former accumulation of iron sulfides, elemental sulfur and reduced organic sulfur species (ROSS). Below the surface region, iron was the dominating element (1–10 mg g−1) present both as iron(II) and iron(III) compounds, which diffused into the wood matrix from corroding iron bolts and other iron items during the time in the sea (1628–1961). Electron microscopy results revealed that iron and sulfur are present in a variety of particles of different sizes and compositions in the surface region, in contrast to the interior where few particles were found. Here, the presence of iron compounds of nano-particle size inside the cell walls enables a close contact between the wood polymers and reactive oxygen species originating from reactions with iron compounds. The presence of ROSS seems to have played an important role as scavengers of reactive oxygen species. Samples with high iron : ROSS ratio displayed evident signs of degradation as indicated by depolymerisation of wood components accompanied by increased acidity due to low molecular organic acids. The observations strengthen the hypothesis of the pro-oxidative and antioxidant properties of iron and ROSS compounds, respectively, and that the chemical activities of these elements play crucial roles in the long term preservation of wooden maritime artefacts.
Aqueous Partitioning of Minor Actinides by Different Processes

Actinide partitioning is a proposed strategy for effective mitigation of the long-term hazards associated with high-level waste (HLW). Octyl-(phenyl)–N,N-diisobutyl carbamoyl methyl phosphine oxide (CMPO) and diphenyl–N,N-diisobutyl carbamoyl methyl phosphine oxide (DφCMPO) are amongst the promising extractants extensively studied since the 1980s for actinide partitioning from wastes of different origin. During the last two decades, substituted malonamide extractants such as N,N'-dimethyl-N,N'-dibutyl tetradecyl malonamide (DMDBTDMA) and N,N'-dimethyl-N,N'-dioctyl hexylethoxy malonamide (DMDOHEMA) have emerged as viable green alternatives to phosphine oxides. During the last decade, diglycolamide-based extractants such as N,N,N′,N′-tetraoctyl diglycolamide (TODGA) and N,N,N′,N′-tetra-2-ethylhexyl diglycolamide (TEHDGA) have received considerable attention due to overwhelmingly favourable extraction and stripping efficiencies of minor actinides from different types of transuranium (TRU) wastes. The focus of the present review is to carry out comparative evaluation of the key physical and chemical properties of these extractants for hydrometallurgical applications. Merits of flow sheets proposed for the separation and recovery of minor actinides from high-level wastes have also been discussed.
ULTRAVIOLET ACTION SPECTRA (280 to 380 nm) AND SOLAR EFFECTIVENESS SPECTRA FOR HIGHER PLANTS

Several ultraviolet (UV) action spectra that typify the responses of higher plants to irradiation by wavelengths between 280 nm and 380 nm are shown. An attempt is made to generate common spectra that may be used, at least temporarily, to represent the effects of UV on such important biological parameters as photosynthesis. The goal is to provide an estimate of plant response to solar UV and to the potential increase in ground level UV postulated for a depleted stratospheric ozone layer. Solar plant damage effectiveness curves are generated under “normal” solar UV conditions, and under an assumed UV increase corresponding to a 16% depletion in total ozone. Additional effects due to ozone depletion are concentrated in the UV‐B region, especially at wavelengths between about 297 nm and 315 nm. Common features of these effectiveness curves are noted, and limitations are pointed out. As expected, no common spectrum has been found that can substitute for any specific spectrum nor that is unique enough to provide more than a limited first approximation of a plant damage spectrum. Additional information must be generated to fulfill this need.
Kinetics of Aldehyde Oxidation by Chlorous Acid

Chlorous acid is known to react with aldehydes. This study investigated the oxidation kinetics of different aldehydes by chlorous acid. Reaction rates with chlorous acid at 25 °C were obtained for formaldehyde (11.0 M−1 s−1), vanillin (0.59 M−1 s−1), veratraldehyde (1.00 M−1 s−1), benzaldehyde (5.6 M−1 s−1), glucose (3.39 × 10−3 M−1 s−1), glycolaldehyde (39.0 M−1 s−1), and 5-formyl-2-furancarboxylic acid (5.2 M−1 s−1). The activation energies varied between 26 and 63 kJ/mol. The rate-determining step was shown to be the addition of chlorous acid to the aldehyde structure. The practical significance of the Cl(III) reaction with aldehyde structures in chlorine dioxide bleaching was discussed. It was concluded that various aldehydes present in cellulosic pulp are at least partly responsible for the consumption of Cl(III) in chlorine dioxide bleaching.
Application of the central composite design to optimization of petroleum hydrocarbons removal from oilfield water using advanced oxidation process

In the last few years, RSM method has been used widely to analyze, optimize and evaluate the interaction of independent factors for chemical, biochemical, and environmental processes. This study examined and evaluated the applicability of this method to manage Oilfield Produced Water to prevent marine environment due to the presence of hard degradable compounds by ozonation process. In this study simulated oil-water sample and a homogenizer reactor was used. The main reactor used in this study was impeinger equipped with sintered glass filter through which the treated oil-water was entered to reactor in the form of discontinuous flow. After ozonation and at the end of the reaction time (60 min), the concentration of oil hydrocarbons was determined by a gas chromatography device equipped with a flame ionization detector. The performance of the central composite design (CCD) approach was evaluated by the F-Value, P-Value, R2, lack of fit test and Adequate Precision parameters to determine the influence of effective factors, including ozonation time, pH, ozone dose, and TPH concentration on the TPH removal efficiency. The mean TPH efficiency obtained from the design of the 30-step experiment resulting from surface-response method was 49.903%, with a standard deviation of 12.47. This study showed the high power of model adopted from the central composite design to predict the hydrocarbons removal from oilfield water using advanced oxidation process, and it was proved that this model can be used alone to determine the design space nature. © Copyright by Polish Academy of Sciences.
Suction Cup Materials and their Potential to Bias Trace Metal Analyses of Soil Solutions: A Review

We reviewed the effects of physical and chemical characteristics of filter materials on trace metal concentrations in soil solutions to evaluate their suitability for porous sections of suction cups. Among the materials described in the literature, e.g. ceramics, Al 2 O 3 , sintered Ni or glass, and various plastic filters, a great variation in bubbling pressure, pore size, permeability, chemical composition and stability, CEC, and trace metal dissolution/precipitation or adsorption/desorption processes was found. A low adsorption capacity suggests plastic materials are suitable, provided the bubbling pressure is high enough. All other materials have disadvantages in one or more properties, e.g. release of trace metal impurities into the soil solution, clogging of pores by precipitation of previously dissolved compounds, or sorption of trace metals. Many reported experiments on sorption of trace metals by various materials are not relevant because of the unrealistic high metal concentrations of the test solutions. Our experiments with realistic concentrations revealed that sorption processes during the extraction may alter trace metal concentrations in soil solutions significantly. Ceramic or Al 2 O 3 cups are commonly used, but they adsorb appreciable amounts of trace metals. Therefore, we conclude that metal fluxes and budgets based on such data have to be interpreted with caution. To improve data comparability, detailed description of suction cup materials in the method sections of papers would be required. Moreover, more development and testing with plastic materials should be done, aimed at the optimization of both physical and chemical properties.
KAPASITAS ANTIOKSIDAN SENYAWA GOLONGAN TRITERPENOID PADA DAUN PRANAJIWA (Euchresta horsfieldii lesch benn)

Isolation, identification, and anti-oxidant assay of triterpenoid compound from Euchresta horsfieldii lesch benn) have been conducted. Maseration of 600 g pranajiwa leaves powder with n-hexane produced 6,1 g n-hexane extract which gave yellow to purple colour change with Lieberman-Burchard reagent. The separation with column chromatography using silica gel 60 obtained 3 fractions (F1, F2, F3) which were then analyzed with triterpenoid test. The positive fraction of triterpenoid (F1) produced 2 g yellow isolate. Infrared spectra indicated that the isolate was a triterpenoid, with characteristic functional groups of OH, –CH, C=O, –C=C, –CH 2 , –CH 3 , and C–O alcohol. Ultraviolet-visible spectra showed broad peak at 217 nm. The result of anti-oxidant capacity test of triterpenoid was 94,67%, showing that triterpenoid from pranajiwa leaves can be use as an anti-oxidant.