Miracle-dz/UniFAR-FTUs huggingface dataset:
CONCENTRATION OF ZINC IN WATER AND BOTTOM SEDIMENTS IN SMALL WATER RESERVOIRS LOCATED IN RURAL AREAS

Depending on its concentration in the environment, zinc can be either an important bio-element for development of living organisms, or a toxic heavy metal. Small water reservoirs are especially sensitive to contamination, as because of their location in the lowest point of the catchment they tend to receive contaminants from its whole area. The purpose of this work was to assess changes in concentration of zinc in surface, supra-bottom and interstitial water, and in the upper layer of sediment, in five small water reservoirs located in rural areas. The reservoirs G1 and G2 were located in a golf course, water body SW was in a village, very close to farmyards, water body P1 was in the middle of a crop field, and water body P2 was on fallow land. For this research, samples were collected once a month, during three vegetation seasons. The water reservoirs contained an elevated average concentration of zinc in water from 0.026 to 0.063 mg dm–3). The average concentration of zinc in the sediments (from 25.8 to 118.2 mg kg–1) classified the examined reservoirs into the geochemical purity class 1. The highest content of zinc was in the village pond. Highly significant correlations were determined between the content of organic matter and zinc in the bottom sediment in the investigated reservoirs. At the same organic matter content, the zinc concentration in the bottom sediments of the rural pond was find-fold higher than in the other reservoirs. The concentration of zinc in water and the factor of its accumulation in the sediment showed a clear seasonal character of changes. In the spring season, concentration of zinc in interstitial water was lower than in the water depth, whereas in the vegetation season, the zinc concentration was observed to rise in all layers, up to over ten-fold in the interstitial water. In the sediment, the zinc accumulation factor changed in a reverse manner, i.e. it reached thee highest values during spring but fell the lowest in autumn.
Biobased polyesters and other polymers from 2,5-furandicarboxylic acid: a tribute to furan excellency

Motivated by the general concern about sustainability and environmental issues, an intense search for renewable-based polymers has grown exponentially in recent years. This search definitely spotlighted polyesters derived from 2,5-furandicarboxylic acid, among other polymers, as some of the most promising, especially due to the resemblance of this renewable monomer to the well-known petroleum-based terephthalic acid, as well as owing to the possibility of preparing innovative materials. The huge number of recent papers and patents about this family of polymers explore aspects as diverse as synthesis with other renewable-based monomers, leading to the preparation of materials with enhanced thermo-mechanical, biodegradability and liquid crystalline properties, among other features. Additional aspects pursued in such studies are innovation in the synthetic approaches or their optimisation, as well as the development of applications for everyday-life objects for example packaging materials, especially bottles, textiles, coating, and toners, among many other uses. Despite this intense activity, little has been reviewed recently about this unique family of polyesters or derived polymers, as the only reviews on the subject date back to the last century. In this perspective, the present review aims at contributing to filling this literature gap, covering recent aspects related with challenges in developing polyesters, polyamides, or other polymers from 2,5-furandicarboxylic acid and their precursors. Emphasis is placed on monomer synthesis, polymerisation reactions, catalysts and applications.
Impact of road fugitive dust on air quality in Beijing, China.

Abstract An integrated Advanced Regional Prediction System–Community Multiscale Air Quality modeling system was employed to investigate the PM10 air pollution issue in Beijing, China, with a focus on assessing contributions from road fugitive dust (RFD). A two-level nested grid domain with spatial resolutions of 12 and 4 km was designed for the study region, and the months of January, April, July, and October in 2006 were taken as target periods for the model simulations. The RFD emission inventory for 2006 base year was developed and provided to the Advanced Regional Prediction System–Community Multiscale Air Quality modeling system to quantitatively assess the PM10 contributions from RFD in Beijing. Further, both baseline and attainment scenarios in 2010 were designed and run to show the RFD impacts on the PM10 air quality in Beijing. Results show that, independent of the total PM10 mass in Beijing, the absolute contribution of RFD to the total PM10 is around 36%. Variations in the PM10 concentrations a.
Do Hexenuronic Acid Groups Represent the Majority of the Carboxyl Groups in Kraft Pulps?

Abstract The formation of hexenuronic acid groups during kraft pulping via demethylation of the 4‐O‐methylglucuronic acid groups attached to the wood xylan backbone was discovered a long time ago. In recent years, the formation of hexenuronic acid groups has attracted new interest and it has been stated that they represent the majority of the uronic acid groups in kraft pulps. However, the values reported in the literature are scattered. Furthermore, the data reported recently are partly in conflict with the earlier observations, which are based on analytical methods of a different type. It is obvious that more reliable and quantitative methods are needed for the determination of hexenuronic acids in pulps in order to assess their influence on factors associated with the bleaching process and pulp quality.
Pulsed Bipolar Electrodeposition of Palladium onto Graphite Powder

The pulsed bipolar electrodeposition of palladium onto 1-2 μm graphite particles was investigated. The amount of palladium deposited was strongly correlated with field intensity, showing an abrupt increase at 2-3 kV/cm. The electrodeposition was successful for frequencies ranging from 500 Hz to 20 kHz, and the amount of deposited palladium was independent of the frequency used. These results demonstrate that the preparation of bipolar electrodeposited catalysts can be achieved within a very large frequency window. Palladium surface area measurements indicate an increase in dispersion with increasing frequency. Sonication of the graphite prior to deposition leads to significantly greater palladium dispersion. Electron microscopy characterization reveals three types of growth: surface-bound, ramified, and amorphous. The surface-bound growth appears as spherical deposits on the order of 5 nm in both dc and pulsed-field experiments. The ramified deposits consist of interconnected 25-50 nm diam spherical structures extending from the graphite particles and appear in the samples prepared at all studied frequencies.
Aluminium solubility mechanisms in moderately acid Bs horizons of podzolized soils

The processes controlling the retention and release of aluminium in acid forest soils are still subject to controversy, and therefore a universal hypothesis as to what mechanisms are operating has not been firmly established. By studying the Bs horizons of Swedish and Swiss podzolized soils, and by analysing data in the literature, we have found that aluminium hydroxide, and in some cases also poorly ordered imogolite, may control Al solubility in moderately acid (pH > 4.2–4.3) Bs horizons. The strongest evidence in support of the presence of a quickly reacting Al(OH)3 pool came from the temperature dependence of Al solubility in a Bs horizon, which was consistent with the reaction enthalpy of an Al(OH)3 phase such as gibbsite, and from the observation that the ion activity product for Al(OH)3 was the same regardless of whether equilibrium was reached from over‐ or undersaturation. The pool of Al(OH)3 is commonly small and may be completely dissolved after large additions of acid. This may be explained by the continuing redissolution of reactive Al(OH)3 to form less soluble imogolite‐type phases. By using the same methods it was found that soil suspensions did not reach equilibrium with poorly ordered imogolite even after 17 days. Thus, imogolite probably does not control Al solubility in the short term in many soils despite the common occurrence of this mineral. This is due to the relatively slow kinetics of imogolite formation and dissolution, especially at low temperatures and at small solution H4SiO4 concentrations.
Surface Segregation Maps Derived from Tight-Binding Ising Model

Surface segregation in transition metals can be analysed within a generalised Ising model,derived from Tight-Binding electronic structure calculations, which identiﬁes three driving forces:the difference in surface energy and atomic volume between the two components and their tendencyto order or phase separate in the bulk. Using this ”three effects” rule, we present here general mapswhich predict the tendency of the solute metal element to segregate (or not) at the surface of a metalmatrix, for the 702 solute/matrix systems that can be formed with transition metal elements. Ourpredictions compare fairly well to the existing ab initio calculations and experimental data availableon these systems. The few exceptions, which mainly concern given matrix elements are discussed indetails.
Electrolytic Reduction of Spent Light Water Reactor Fuel Bench-Scale Experiment Results

A series of experiments were performed to demonstrate the electrolytic reduction of spent light water reactor fuel at bench-scale in a hot cell at the Idaho National Laboratory Materials and Fuels Complex. The process involves the conversion of oxide fuel to metal by electrolytic means, which would then enable subsequent separation and recovery of actinides via existing electrometallurgical technologies, i.e., electrorefining. Four electrolytic reduction runs were performed at bench scale using ∼500 ml of molten LiCl–1 wt% Li2O electrolyte at 650°C. In each run, ∼50 g of crushed spent oxide fuel was loaded into a permeable stainless steel basket and immersed into the electrolyte as the cathode. A spiral wound platinumwire was immersed into the electrolyte as the anode. When a controlled electric current was conducted through the anode and cathode, the oxide fuel was reduced to metal in the basket and oxygen gas was evolved at the anode. Salt samples were extracted before and after each electrolytic reduction run and analyzed for fuel and fission product constituents. The fuel baskets following each run were sectioned and the fuel was sampled, revealing an extent of uranium oxide reduction in excess of 98%.
Chemical investigation of ceylonese plants. Part VII. Extractives of Calophyllum thwaitesii Planch and Triana and Calophyllum walkeri Wight (Guttiferae)

The bark and timber extractives of C. thwaitesii Planch and Triana and C. walkeri Wight have been studied. The former contained taraxerol and friedelin in the bark whilst the latter had taraxerol and β-simiarenol. In addition a new di-isoprenylated xanthone, named thwaitesixanthone, has been isolated from the former and shown to be 13-hydroxy-3,3,10,10-tetramethyl-3H,10H-dipyrano[3,2-a:2′,3′-i]xanthen-14-one (IV) while calabaxanthone, 5-hydroxy-8-methoxy-2,2-dimethyl-7-(3-methylbut-2-enyl)-2H-pyrano[3,2-b]xanthen-6-one (I) was isolated from the latter. The timber extractives of both species gave 1,5-dihydroxyxanthone, 1,7-dihydroxyxanthone, jacareubin (IIa), and β-sitosterol. The latter species also contained guanandin (VIII), 1,3,5-trihydroxy-2-(3-methylbut-2-enyl)xanthone (X), and the new metabolite 1,5-dihydroxy-2,3-dimethoxyxanthone (IX).
Behavioral Changes in Gym Attending Due to COVID-19 Pandemic: A Descriptive Survey

Introduction: On the declaration of the COVID-19 pandemic lockdown clearance in Saudi Arabia, the high-profile precautions were applied as a major step to resume the normal life activities and to coexist with the pandemic. One of those resumed activities is the reopening of the gym and fitness centers. The perception and the commitment with safe precautions in terms of personal hygiene and sterilization have dramatically changed due to the COVID-19 pandemic. The purpose of this study was to assess the behavior of gym attendees toward preventive precautions prior to the pandemic and the behavioral changes that will be accommodated after the new policy and procedure of attending a gym and fitness centers. Methods: A cross-sectional descriptive study was conducted in February 2020, a 1 month prior to the complete lockdown announcement in Saudi Arabia as a result of the COVID-19 pandemic outbreak. An electronic questionnaire was provided during a personal interview with gym and fitness centers' participants. Results: The majority of participants never use sterile wipes or any sterile product before or after using gym equipment (61.6%), and 35.4% of gym attendants do not use any sterilization materials distributed through fitness centers. In addition, most of the participants have had an episode of skin infections or respiratory infection at the fitness center for the past 12 months (22.2%), whereas 80.8% do not know about tinea microbial that causes athlete's foot, and 65.7% of them utilize the shower in the gym after their workout. Conclusion: The lack of awareness of previous and new gym members regarding safety precautions during indoor exercise should be overcome by more future educational intervention and emphasizing on following the Ministry of Sports in Saudi Arabia, even after the complete clearance of COVID-19 pandemic.
Lead intoxication: Histological and oxidative damage in rat cerebrum and cerebellum

The present experiment was designed to study the neurotoxic consequences of lead exposure on antioxidant enzymes like glutathione, glutathione peroxidase, super oxide dismustase, and catalase along with structural changes both in cerebrum as well as cerebellum. Lead was administrated orally in the doses of 50 mg/kg for a period of 8 weeks and study was performed at the end of exposure. Decrease in the concentration of all the antioxidant enzymes was observed, and after lead treatment, transverse sections of cerebrum showed degeneration of neurons. Disruption of normal arrangement of cell layers was seen. Cells were bigger in size with large vascular spaces around them. Lead treatment for 8 weeks also was enough to disrupt the normal arrangement of cellular layer of cerebellum. Large spaces in between purkinje cell layer and granular layer were seen. J. Trace Elem. Exp. Med. 17:45–53, 2004. © 2004 Wiley-Liss, Inc.
Thermal stability and thermo-mechanical properties of magnetron sputtered Cr-Al-Y-N coatings

Cr1−xAlxN coatings are promising candidates for advanced machining and high temperature applications due to their good mechanical and thermal properties. Recently the authors have shown that reactive magnetron sputtering using Cr-Al targets with Al/Cr ratios of 1.5 and Y contents of 0, 2, 4, and 8 at % results in the formation of stoichiometric (Cr1−xAlx)1−yYyN films with Al/Cr ratios of ∼1.2 and YN mole fractions of 0%, 2%, 4%, and 8%, respectively. Here, the impact of Y on thermal stability, structural evolution, and thermo-mechanical properties is investigated in detail. Based on in situ stress measurements, thermal analyzing, x-ray diffraction, and transmission electron microscopy studies the authors conclude that Y effectively retards diffusional processes such as recovery, precipitation of hcp-AlN and fcc-YN, grain growth, and decomposition induced N2 release. Hence, the onset temperature of the latter shifts from ∼1010 to 1125 °C and the hardness after annealing at Ta=1100 °C increases from ∼32 to .
High‐field and current‐induced positive charge in thermal SiO2 layers

The generation of a bulk positive charge in SiO2 layers of silicon gate metal‐oxide‐silicon (MOS) devices, under the conditions of high‐field and charge injection is studied. The time dependence of the positive charge and its spatial distribution as a function of the oxide thickness and electric field are all consistent with an impact ionization‐recombination model which takes into account both the spatial and the field dependence of the ionization probability. The nature of the ionization, either band‐to‐band, or traps ionization, is still unknown. Bulk positive charge of the same nature is also formed in Al gate oxides. Nevertheless, it was not always observed in previous works since a much larger Si‐SiO2 interfacial positive charge is also generated in these samples.
Universal Mixing Rule for Cubic Equations of State Applicable to Symmetric and Asymmetric Systems: Results with the Peng−Robinson Equation of State

A mixing rule for cubic equations of state (CEoS) applicable to all types of system asymmetriesreferred to hereafter as the universal mixing rule (UMR)is proposed. For the cohesion parameter of the CEoS, the mixing rule involves the Staverman−Guggenheim part of the combinatorial term and the residual term of the original UNIFAC Gibbs free energy expression. For the covolume parameter of the CEoS, the quadratic concentration-dependent mixing rule is used with the combining rule for the cross parameter bij = [1/2(bi1/2 + bj1/2)]2. This UMR is applied to the volume-translated and modified version of the Peng−Robinson equation of state of Magoulas and Tassios (Fluid Phase Equilib. 1990, 56, 119), leading to what is referred to as the UMR−PR model. Very satisfactory results are obtained using the existing interaction parameters of the original UNIFAC model for vapor−liquid equilibrium predictions at low and high pressures for a wide range of system asymmetries including mixtures containing polymers. Satisfacto.
PREDICTION OF RUNNING FORCES IN HIGH CURVATURE WELL BORES USING FINITE ELEMENT ANALYSIS AND ARTIFICIAL NEURAL NETWORK

Estimation of the vertical force at the kick-off point (k.o.p) is of major concern to field engineers involved in horizontal drilling. Prior knowledge of the level of magnitude of the vertical force assists engineers in selecting appropriate hole paths to be drilled in order to minimize the risk of pipe failure. Current methods employed to approximate the vertical force are based on simple mathematical models that are not necessarily representative of field conditions. This paper presents a new approach based on the use of Artificial Neural Network (ANN) to predict the vertical forces at the k.o. p, which is required to push pipes through curved hole sections. The artificial neural network learns the relationship between field variables and the vertical forces through generated results using a finite element package and offers a quick and efficient way of estimating vertical forces at the k.o. p for various field conditions. The effect of pipe stiffness, hole radius (build-up rate), hole roughness, and the horizontal drag force applied at the end of build (e.o.b) are investigated. The finite element analysis and ANN results showed that the running force variation at the k.o. p increases as the horizontal force, buildup rate and drag increase. The results also showed that the pipe stiffness has negligible effect on the variation of running force at high buildup rate whereas a significant effect is observed at low buildup rate.
A collaborative platform to empower local actions against energy poverty

Energy Poverty alleviation measures often require large public investments. However, successfully targeting the beneficiaries can be hard due to the territorial specificity of the issue. Decentralized collective impact ecosystems leveraging on social innovation schemes of public authorities, creating shared value for market actors and ensuring the widest outreach to the voluntary sector would enhance the effectiveness of coping programs. A multi-disciplinary platform to tackle energy poverty composed of academic institutions, private stakeholders and charities is presented in this paper. Charities offer the confidence framework for a “door-to-door” engagement, academic institutions provide technical and socio-economic significance, bridging with the local administration. Profit companies contribute in the context of their CSR/CSV and explore new possible business models. A first project involved 60 households from six cities in North-West Italy. An international-wide do-ityourself company donated customized kits of energy saving devices, designed in accordance with building energy needs. Inputs are based on site surveys disseminated by charity volunteers, which investigated socio-economic aspects too. Volunteers attended a dedicated educational program on domestic energy appliances, household economy and energy billing beforehand. The first outcomes of the project are presented herewith.
Nonequilibrium molecular dynamics simulations of steady-state heat and mass transport in distillation

Coupled transport phenomena across gas/liquid interface, relevant for distillation, were studied by nonequilibrium molecular dynamics simulations. The simulations were set in the context of bulk irreversible thermodynamics. It was then shown that mole fraction profiles in the liquid phase and the gas phase of ideal isotope mixtures are linear. For nonideal mixtures, Fick`s law cannot be applied in the interface region, because the activity coefficients change dramatically across the interface. Fourier`s law has a constant heat conductivity for both types of liquid mixtures but not for gas mixtures. The coupling between heat and mass transfer becomes negligible for distillation in the special case of ideal mixtures with constant molal overflow. In all other cases, the heat of transfer contributes significantly to the heat flux and causes deviations from Fourier`s law in the gas phase. This all means that coupled flux equations are needed to describe distillation and that the properties of the surface are important for a description of the heat and mass fluxes involved. The value of the heat of transfer has a bearing on the calculation of the number of theoretical stages in the column. When considered as a function of distance from the surface, the local entropymore » production rate has a peak or a shoulder (depending on the conditions) slightly into the vapor. The entropy production rate in the liquid cannot be neglected compared to that of the gas. The second law efficiency of distillation was quantified from this knowledge. « less
Intermolecular potential functions from spectroscopic properties of weakly bound complexes

Goal is to consolidate the information from high resolution spectroscopy of weakly bound cluster molecules through a theoretical model of intermolecular potential energy surfaces. The ability to construct analytic intermolecular potential functions that accurately predict the interaction energy between small molecules will have a major impact in chemistry, biochemistry, and biology. This document presents the evolution and capabilities of a potential function model developed here, and then describes plans for future developments and applications. This potential energy surface (PES) model was first used on (HCCH){sub 2}, (CO{sub 2}){sub 2}, HCCH - CO{sub 2}; it had to be modified to work with HX dimers and CO{sub 2}-HX complexes. Potential functions have been calculated for 15 different molecular complexes containing 7 different monomer molecules. Current questions, logical extensions and new applications of the model are discussed. The questions are those raised by changing the repulsion and dispersion terms. A major extension of the PES model will be the inclusion of induction effects. Projects in progress include PES calculations on (HCCH){sub 3}, CO{sub 2} containing complexes, (HX){sub 2}, HX - CO{sub 2}, CO{sub 2} - CO, (CO{sub 2}){sub 3}, and (OCS){sub 2}. The first PES calculation for a nonlinear molecule will be formore » water and ammonia complexes. Possible long-term applications for biological molecules are discussed. Differences between computer programs used for molecular mechanics and dynamics in biological systems are discussed, as is the problem of errors. 12 figs, 74 refs. (DLC)« less