Miracle-dz/UniFAR-FTUs huggingface dataset:
Fe3O4 nanoparticles: a highly efficient and easily reusable catalyst for the one-pot synthesis of xanthene derivatives under solvent-free conditions

Magnetically separable Fe3O4 nanoparticles supply an environment- ally friendly procedure for the synthesis of 14-aryl-14H-dibenzo(a,j)xanthene and 1,8-dioxooctahydroxanthene derivatives. These compounds were obtained in high yields and short reaction times by the reaction of dimedone and 2-naph- thol with various aromatic aldehydes under solvent-free conditions. The cata- lyst could be easily recovered using an external magnet and reused for six cyc- les with almost consistent activity.
Short‐term Reestablishment of Soil Water Repellency after Wetting: Effect on Capillary Pressure–Saturation Relationship

Soil water repellency is known to be a dynamic property, which varies in the short term or between seasons. In the short term, its temporal nature is often studied based on soil water content, assuming that it is reestablished after the soil dries out. In this study, we examined the reestablishment of soil water repellency after wetting and subsequent drying. The reestablishment process was studied on: (i) natural water-repellent soils (WRS) subjected to different leaching rates; and (ii) wettable sand subjected to wetting-drying cycles with dissolved organic matter (DOM) solution. After air drying, the soils were packed in columns, rewetted, and from the maximum height of capillary rise for the target soil (H eq1 ) and that of a "reference soil" (H eq0 ) the equilibrium (static) contact angle (ω eq1 ) was calculated, assuming that for the reference soil the contact angle ω eq0 = 0. Increasing the leaching fraction of an initially WRS resulted in a decrease in ω eq1 values. For an initially wettable soil, increasing wetting-drying cycles with DOM solutions resulted in an increase in ω eq1 . The variations in cosω eq1 were reflected in a similar ratio for the capillary-pressure-saturation relations (CSR). The prediction from scaling the "reference soil" CSR curve by cosω eq1 was found to be satisfactory, but more accurate where the effective saturation S 0.5, organic matter is more likely to detach and dissolve, changing the properties of the soil solution by altering its surface tension and the soil particles' surface, i.e., ω eq1 .
Levels of Some Heavy Metals in Tissues of Bonga Fish, Ethmallosa fimbriata (Bowdich, 1825) from Forcados River

The levels of some heavy metals in the tissues of E. fimbriata from Forcados River were investigated to assure the suitability of the fish for human consumption. A total of 344 E. fimbriata fish samples were purchased from fishermen on the bank of the river at Burutu fortnightly for six months during the dry season. Water and sediment samples from the river were also collected using sterile 1litre and 500 ml plastic container for water and sediment samples respectively. All three samples (fish tissues, water and sediment) were analyzed for levels of heavy metals (zinc, cadmium, copper, lead and nickel) using the Atomic Absorption Spectrophotometer. Tissues of E. fimbriata analyzed accumulated some heavy metals. Water and sediment samples from Forcados River were also observed to have heavy metals. The levels of zinc in tissues of E. fimbriata, water and sediment samples were not significantly (P>0.05) different. The levels of cadmium, copper, lead and nickel in tissues of E. fimbriata and water were also not significantly (P>0.05) different. However, sediment samples had significantly (P<0.05) higher levels of cadmium, copper, lead and nickel than in the tissues of E. fimbriata and water samples. The observed levels of zinc and cadmium in this study exceeded the WHO maximum permissible limit while copper, lead and nickel were within the WHO set limits. E fimbriata from Forcados River are contaminated with heavy metals and may be toxic to other aquatic fauna and poisonous to human consumers.
SÍNTESIS Y BIODEGRADACIÓN DE POLIHIDROXIALCANOATOS: PLÁSTICOS DE ORIGEN MICROBIANO

Polyhydroxyalkanoates (PHA) are biopolyesters synthesized by numerous microorganisms as an intracellular carbon and energy storage compound, and they have physical and chemical properties similar to those of petroleum-based plastics. They have been extensively studied since 1980, nowadays they are still an important research topic as substitutes of conventional plastics since PHA are biodegradable and synthesized from renewable resources. They also have an important application as biocompatible materials in the biomedical and pharmaceutical field. In this work is presented an extensive bibliographic review about scientific research on the biosynthesis and biodegradation of PHA, the status of its industrial production and commercialization, and the future perspectives regarding the study and application of these bioplastics.
A green route for the synthesis of novel optically active poly(amide–imide) nanocomposites containing N-trimellitylimido-l-phenylalanine segments and modified alumina nanoparticles

In the present study, novel optically active poly(amide–imide)/alumina nanocomposites (PAI/Al2O3 NCs) containing different amounts of modified α-Al2O3 nanoparticles (NPs) were synthesized using the ultrasonic-assisted technique. To improve NPs dispersion and increase the possible interaction between NPs and PAI matrix, the surface of α-Al2O3 NP was modified with bioactive diacid coupling agent. The PAI chains were formed from the polycondensation of N-trimellitylimido-l-phenylalanine diacid with 1,5-diamino naphthalene under green conditions. The obtained polymer and inorganic metal oxide NPs were used to prepare chiral PAI/Al2O3 NCs through the ultrasonic irradiation. PAI/Al2O3 NCs were characterized by Fourier transform infrared spectra, x-ray diffraction patterns, field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and ultraviolet–visible (UV-Vis). TGA results confirmed that the heat stability of the prepared NP-reinforced composites was improved compared with the pure polymer. In addition, TEM and FESEM images showed that NPs were dispersed into the polymer matrix at nanoscale.
Evaluation of TCE and MTBE in situ Biodegradation: Integrating Stable Isotope, Metabolic Intermediate, and Microbial Lines of Evidence

Compound specific isotope analysis (CSIA) was used to investigate biodegradation of trichloroethene (TCE) and methyl tert‐butyl ether (MTBE) at contaminated field sites in Alaska and New York State, respectively. At both sites, geochemical conditions and the presence of metabolic intermediates (cis‐1‐2‐dichloroethene and tert‐butyl alcohol [TBA]) suggested the potential for biodegradation of TCE and MTBE, respectively. Given that in both cases these metabolic intermediates could also have been present as cocontaminants in the source zone, CSIA was undertaken to evaluate the possibility of in situ biodegradation. At the TCE‐contaminated field site in Alaska, δ13C values of TCE in ground water determined in this study showed no evidence of biodegradation (mean δ13C of −27.0 ± 1.0‰ for nine wells), and quantitative‐polymerase chain reaction analyses of ground water from four wells found no evidence of dechlorinator Dehalococcoides sp. at this site. At the MTBE‐contaminated field site in New York, TBA was present in the ground water but was not present in gasoline sampled from underground storage tanks (UST) on‐site, suggesting that at this site, TBA was potentially a metabolite of MTBE biodegradation rather than a cocontaminant. However, at all sampling times and locations, δ13C and δ2H values of MTBE in ground water were within range of published values for undegraded MTBE in gasoline. While the occurrence of a small extent of in situ MTBE biodegradation cannot be ruled out, the findings suggest that it is more likely that multiple gasoline spills occurred through time, and while present day USTs do not contain TBA as a cocontaminant, gasoline spilled at the site in the past may have. At both contaminated field sites, CSIA, chemical, and microbiological lines of evidence suggest that biodegradation was not a significant attenuation process. The results of these two studies underscore the need for an integrated approach to site assessment that draws on measurements of metabolic intermediates, analysis of stable isotopes, and microbial evidence to give a reliable assessment of in situ biodegradation at contaminated field sites.
THE NUCLEATION RATES OF SILICON NANOFILMS

An approach for the calculation of thin film nucleation rate, J is highlighted in this paper. Nucleation is a random process in which the number of nuclei formed in a fixed interval of time is a random quantity and subjected to statistical laws. This normally applies to either the frequency of appearance at time, t of nuclei per unit volume or area of the system under consideration, based on the classical kinetic theory of nucleation. In this work, the nucleation rates, J was calculated using a visual basic programming by identifying appropriate parameters from the pre-exponential factor, contact angle, desorption energy, diffusion energy, supersaturation ratio, etc.) and performing trial and error execution. It was observed that, from the different plots of nucleation rates, J for vapour/liquid and liquid/solid transition was found to lie within the reasonable experimental ranges.
ALGAL FLORA OF AIN HELWAN I. ALGAE OF THE WORM SPRING

Seasonal water samples were collected during the period of April 2004 to January 2005 and physico-chemical analyses were performed for each sample. Isolation and identification of the different algal species were carried out. Concerning the physical water characteristics, temperature of the water samples, during the period of study, ranged 26 - 30 oC, pH values ranged 6.9 – 7.78 and light intensities, received by the surface of shallow water of the spring, ranged 26.4-115 Klux. On the other hand the values of chemical water characteristics (anions, cations, micronutrients) were seasonally fluctuated and no detection of cobalt and cadmium were recorded. The total identified algal flora in the water samples of the four seasons recorded 209 species and 116 genera belonging to 8 algal divisions; Cyanobacteria, Chlorophyta, Bacillariophyta, Chrysophyta, Xanthophyta, Euglenophyta, Dinophyta and Charophyta. Cyanobacteria were the maximally represented division (91 species and 29 genera) during the period of study, followed by Chlorophyta (59 species and 45 genera), Bacillariophyta (52 species and 35 genera), Chrysophyta and Euglenophyta were represented each by (2 species and 2 genera). While, the least representative algal divisions were Charophyta, Dinophyta and Xanthophyta (1 species and 1 genera). The largest algal biomass was recorded in winter sample (138 species and 92 genera) followed in descending order by autumn (87 species and 56 genera), summer (71 species and 45 genera) and spring samples (48 species and 25 genera). It seemed that the diversity of algal flora in water samples was mainly controlled by and significantly correlated with some physico-chemical characteristics of water samples.
Dinuclear transition metal complexes in carbon nanostructured materials synthesis

Carbon nanomaterials (CNMs) were prepared with two similar techniques using organometallic complexes as catalysts precursors. Chemical vapour deposition (CVD) and pyrolysis with chlorine gas approaches were employed in order to explore the effect of dinuclear transition metal compounds [Fe2(CO)6(μ-S2C6H2X2), (X=OH, Cl)] in synthesis of CNMs. Our to-date results have shown these complexes generate different carbonaceous materials when they are used in bulk, it was also observed that their performances in synthesis differ even though these compounds are analogous. With X=OH complex used in CVD process, metal nanoparticles of ca. 20–50 nm in size and embedded in carbon matrix were obtained. X=C1 complex has been used in pyrolysis experiments and showed an entire volatilisation or no reaction, depending on selected temperature. Furthermore, obtaining of a new tetranuclear iron cluster is presented in this work.
Sensitivity of PBL parameterization schemes of Weather Research Forecasting Model and coupling with AERMOD in the dispersion of NOX over Visakhapatnam (India)

An attempt has been made to develop a pre-processor coupler for offline coupling of atmospheric mesoscale model (WRF) with a dispersion model (AERMOD) to estimate the ground level concentrations due to industrial sources over a coastal city, Visakhapatnam, India. To integrate AERMOD in standalone mode, surface and upper meteorological observations and various planetary boundary layer (PBL) parameters with good temporal resolution are required, that are absent for most locations in India. We have developed an integrated WRF-AERMOD modeling system that gets required PBL parameters the pre-processor coupler. Using this model, evaluation of the dispersion of nitrogen oxides (NOX) over Visakhapatnam during summer month with emission inventory of elevated point sources of various industries is conducted. Sensitivity studies of PBL schemes of WRF after validation reveal that the non-local schemes, Yonsei University (YSU) followed by Asymmetric Convective Model version 2 (ACM2), captured well the characteristic variations of surface meteorological variables, vertical atmospheric structure. After validating with monitored air quality data, it is found that the integrated model with YSU followed by ACM2 is good in simulating ground level concentrations of NOX. The present work advocates that the developed modeling system is useful for better assessment of pollution dispersion over coastal regions. © 2015 Curtin University of Technology and John Wiley & Sons, Ltd.
Preparation and characterisation of green nanocomposites of biodegradable poly(vinyl‐alcohol‐co‐ethylene) and wood dust

Purpose – The purpose of this paper is to report the preparation and characterisation of nanocomposites, which are made of biodegradable poly(vinyl‐alcohol‐co‐ethylene) and wood dust. These nanocomposites can aptly be termed as green by nature as they are totally non‐toxic and ecofriendly.Design/methodology/approach – Sample films containing 5, 10 and 15 wt% fillers are prepared by conventional solvent casting technique using glass plates as casting surfaces. The dispersion of filler in the polymer matrix is investigated by transmission electron microscope (TEM) analysis. Physical and chemical properties of the films are studied by various characterisation techniques (FTIR, X‐ray diffraction (XRD), TEM and TGA). Findings – TEM analysis reveals that the average particle size of the nanodispersed filler in the nanocomposite materials is in the range of 12‐25 nm, which shows that a greater extent of matrix penetrated into fibre capillaries of wood dust. These results are supported by the XRD findings also. Wo.
Ir nanoparticles-anchored reduced graphene oxide as a catalyst for oxygen electrode in Li–O2 cells

Iridium nanoparticles-anchored reduced graphene oxide (Ir-RGO) was prepared by simultaneous reduction of graphene oxide and Ir3+ ions and its catalytic activity for oxygen electrode in Li–O2 cells was demonstrated. Ir particles with an average size of 3.9 nm were uniformly distributed on RGO sheets. The oxygen reduction reaction (ORR) was studied on an Ir-RGO catalyst in non-aqueous electrolytes using cyclic voltammetry and rotating disk electrode techniques. Li–O2 cells with Ir-RGO as a bifunctional oxygen electrode catalyst were subjected to charge–discharge cycling at several current densities. A discharge capacity of 9529 mA h g−1 (11.36 mA h cm−2) was obtained initially at a current density of 0.5 mA cm−2 (393 mA g−1). A decrease in capacity was observed on increasing the current density. Although there was a decrease in capacity on repeated discharge–charge cycling initially, a stable capacity was observed for about 30 cycles. The results suggest that Ir-RGO is a useful catalyst for rechargeable Li–O2 cells.
Polymeric Sorbents for Bile Acids. 5. Polyacrylamide Resins with Ammonium-Containing Pendants

Isotherms have been determined for the sorption of bile salt anions, generally glychocolate (GCA - ), in Tris buffer by cross-linked polyacrylamide resins with ammonium-containing pendent groups having the general structure of P-{(CH 2 ) n N + R 2 Cl - }mR, where R is H or a CH 3 group, and n and m are integers in the range of 2-12 and 1-3, respectively. The sorption capacity increases with the number of ammonium groups per pendant, in accord with the primary importance of electrostatic interactions. In general, the binding affinity of the resins for GCA - also increases with an increase in the hydrophobicity of the pendants. The isotherms for the binding of GCA - by the resins with long hydrophobic spacers have a normal Langmuir shape, while a distinct S-shape is observed for the sorption by resins with shorter spacers. The S-shaped isotherms indicate a positive cooperativity in the binding, probably due to hydrophobic interactions and H-bonding among bile salt anions bound at adjacent positions within the resin beads. On the basis of the sorption characteristics, it is proposed that the binding is accompanied by the development of a considerable degree of order within the beads, involving either the formation of pendent group-bile salt anion reversed mixed micelles or conventional micelles, depending on pendant structure. The resins with C 12 spacers exhibit binding properties that are significantly superior to those of cholestyramine, the bile acid sequestrant currently used clinically for the treatment of hypercholesterolemia.
Do NAD and NAT form in liquid stratospheric aerosols by pseudoheterogeneous nucleation

Laboratory data of the freezing of nitric acid hydrates (NAD, NAT) from HNO3/H2O and HNO3/H2SO4/H2O solution droplets have been evaluated with respect to a “pseudoheterogeneous” (surface-induced) nucleation mechanism of NAD and NAT, which has been argued to possibly lead to the formation of polar stratospheric clouds (PSCs). In addition, a parametrization of pseudoheterogeneous nucleation of NAD and NAT suggested recently (Tabazadeh et al. J. Phys. Chem. A 2002, 106, 10238−10246) has been analyzed, showing that this parametrization should not be used in stratospheric modeling studies. The analysis of several laboratory data sets yields an upper limit of the pseudoheterogeneous nucleation rate coefficient of NAD of 2.2 × 10-5 cm-2 s-1. In contrast, the upper limit of the pseudoheterogeneous nucleation rate coefficient of NAT could not be constrained satisfactorily, since formation of NAT has not been observed at stratospheric conditions in laboratory experiments applying small droplets. Maximum NAD product.
Extended cross-section adjustment method to improve the prediction accuracy of core parameters

An extended cross-section adjustment method has been developed to improve the prediction accuracy of target core parameters. The present method is on the basis of a cross-section adjustment method which minimizes the uncertainties of target core parameters under the conditions that integral experimental data are given. The present method enables us to enhance the prediction accuracy better than the conventional cross-section adjustment method by taking into account the target core parameters, as well as the extended bias factor method. In addition, it is proved that the present method is equivalent to the extended bias factor method when only one target core parameter is taken into account. The present method is implemented in an existing cross-section adjustment solver. Numerical calculations verify the derived formulation and demonstrate an applicability of an adjusted cross-section set which is specialized for the target core parameters.
Utilization of Titanate Nanotubes as an Electrode Material in Dye-Sensitized Solar Cells

In this study, titanate H 2 Ti 3 O 7 nanotubes with a multiwall structure, synthesized by a hydrothermal process, were successfully used as an electrode material for dye-sensitized solar cells. The best efficiency, 7.5%, was achieved for an opened cell under illumination of simulated AM 1.5 solar light (100 mW cm -2 ). The relationship between the photovoltaic performance and physicochemical properties of titanate nanotube was also investigated.
Swelling kinetics and release characteristic of crosslinked chitosan : polyether polymer network (semi-IPN) hydrogels

The aqueous swelling kinetics of a series of crosslinked chitosan (cr-CS) with glutaraldehyde (GA) interpenetrating polyether hydrogels have been studied as functions of pH, the N-deacetylation degree of chitosan, the amount of crosslinking agent, the electrolyte composition in solution, temperature, and gel composition. Based on these results, the swelling mechanism of the hydrogels was discussed. The release profiles of chlorhexidini acetas from the semi-IPN were also investigated. © 1994 John Wiley & Sons, Inc.
Selected Ion Monitoring – Gas Chromatography/Mass Spectrometry Determination of Halothane Fumes in Operating Theatres

Halothane vapour, used as an inhaled anaesthetic for narcosis, is released during surgical operations causing occupational exposure to medical staff and nurses. The current work continues the controversial issues related to the biological side effects of halothane, and gives a simple method for sampling and determining the air concentration of the anaesthetic in different rooms used for surgical operations. Air contaminants were collected on active charcoal, using a portable pump. Liquid extraction with toluene was followed by injection of the eluate onto a GC capillary column coupled to a quadrupole mass detector. The method was validated with respect to linearity, precision and accuracy. The concentration of halothane in the air was found to depend on room volume, air ventilation rate inside the theatres, and on the technical condition of the vaporiser and anaesthesia devices. Introduction
Comparison of two treatment couch model in Monaco treatment planning system

Objective To construct the uniform electron density couch model (model A ED=0.25) and two components non uniform electron density couch model (model B FD=0.5and foam core=0.1) in the Monaco treatment planning system for the iBEAM® evo Extension 415, and to compare which model can better quantify the treatment couch influence on radiation dose. Methods Phantom was positioned in the center of the couch, the attenuation of the couch was evaluated with 6 MV for a field size of 10 cm×10 cm. Dose measurements of couch attenuation were performed at gantry angles from 180.0° to 122.8°, using a 0.125cc semiflex ionization chamber (PTW), isocentrically placed in the center of a homogeneous cylindrical phantom. Each experimental setup was first measured on the linear accelerator and then reproduced in the TPS.By adjusting the relative-to water electron density (ED) values of the couch, the measured attenuation was replicated. The model accuracies of the model A and model B were evaluated by comparing the measured and calculated results at the minimum computational grid (2 mm) and maximum computing grid (5 mm), respectively. Results The maximum measured and calculated percentage deviation for the central phantom position was 4.01%. The couch model was included in the TPS with a uniform ED of 0.25 or a 2 component model with a fiber ED=0.5 and foam core ED=0.1. For model A and B under 2 and 5 mm voxel grid size, the mean absorbed dose with couch was reduced to 0.61%, 0.84%, 0.71% and 0.92% from 2.8% without couch. Conclusions Model A has a good agreement between measured and calculated dose distributions for all different voxel grid sizes and gantry angles. It can accurately describes the dose perturbations due to the presence of the couch and should therefore be used during treatment planning. Key words: Carbon fiber treatment couch; Treatment couch model; Monaco treatment planning system; Dose attenuation