Miracle-dz/UniFAR-FTUs huggingface dataset:
Comparison in processability and mechanical and thermal properties of ethylene–octene copolymer crosslinked by different techniques

The crosslinking of metallocene ethylene–octene copolymer was investigated. The crosslinked polymers were prepared using two different techniques, i.e., peroxide crosslinking and silane–water crosslinking. In the former, the crosslinking reaction was conducted in a twin-screw extruder, in the presence of dicumylperoxide. In the latter, the polymer was first grafted with vinyl trimethoxysilane in the extruder and subsequently crosslinked with water. The paper aims at investigation of the differences between these two techniques, in terms of processing and product mechanical and thermal properties. The results showed that the silane-crosslinked polymers could be prepared with much higher gel contents than the peroxide-crosslinked samples. The silane-crosslinked polymers also retained the elastomeric characteristics of the pure polymer and showed remarkably higher extensibility, better thermal stability, and energy storage capacity. An explanation for the property differences between peroxide-crosslinked and silane-crosslinked polymers was proposed. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1179–1185, 2004
Isolation and Partial Characterisation of Native Starches of new Banana and Plantain Hybrids (Musa spp.) in Comparison with that of Plantain Variety Orishele

Native starches were extracted from four new banana hybrids (CRBP 14, CRBP 39, FHIA 17 and FHIA 21) and from Orishele, a plantain variety (Musa spp) used as control. Purity (determined by the polarimetric method), iodine complex absorption spectrum (conducted according to Garcia and Lajolo), size and shape of granules (determined with a scanning electron microscope and an optical microscope equipped with a micrometer), swelling power and solubilization patterns (determined according to Leach et al.) were the characteristics under study. For the four banana hybrids, starch purities range from 96.55 to 97.83%, whereas it stands at a medium value in the case of the control (Orishele variety). The absorption maxima of the starch-iodine complexes for the five cultivars occurred between 620 and 630 nm, with absorption averages ranging between 1.11 and 1.85%. Again, the control variety Orishele has medium value for iodine absorption. The majority of starch granules is of oblong shape, and their lengths range from 3.33 to 56.66 μm. CRBP 14 and CRBP 39 have the largest granule sizes, followed by Orishele; hybrids FHIA 21 and FHIA 17 having the smallest sizes. At high temperatures hybrid FHIA 17 shows the lowest increase of swelling and solubilisation. This hybrid also presents the lowest setback, swelling and solubilisation values. This hybrid also has the smallest starch granule sizes together with the lowest iodine absorption. Apart from starch setback, the other three hybrids (CRBP 14, CRBP 39 and FHIA 21) show characteristics that are superior to those of the control. Hybrid FHIA 17 can be classified as of sweet banana type, whereas the three other hybrids are of plantain type.
Synthesis and characterization of PLA nanocomposites containing nanosilica modified with different organosilanes I. Effect of the organosilanes on the properties of nanocomposites: Macromolecular, morphological, and rheologic characterization

Polylactide nanocomposites containing different loadings of nanosilica were prepared by employing bulk ring opening polymerization from lactide. Nanosilica was used as such and after surface treatment with different amounts of two distinct silanes. The effects on the properties of the material were evaluated comparing the samples containing organosilane-modified nanosilica with poly(lactic acid) (PLA) containing unmodified nanosilica. A standard linear PLA and an industrial “film grade” PLA (PLA Natureworks 4032D) were used as reference. Pure silica tends to decrease the molecular weight of the material, deactivating the catalytic system but when silanes are present on the surface, molecular weights are similar to the ones of standard and industrial PLA. Transmission electron microscopy analysis shows that silanes improve the dispersion of the mineral, while rheologic curves suggest that when silanes are present melt viscosity increases markedly at zero shear and decreases faster as the shear rate increases. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Effects of elevated temperature and nitrogen fertilization on nitrogen metabolism and nutrient status of two coniferous species

The effects of soil warming and nitrogen (N) fertilization on nitrogen metabolism and nutrient status of Picea asperata Mast. and Pinus tabulaformis Carr. seedlings were studied in this paper. Infrared heaters increased monthly average soil and air temperature by 2.6 and 2.1°C above the ambient, respectively. Ammonium nitrate (NH4NO3) was added in an amount equivalent to an additional 25 g N m−2 a−1. Interestingly, soil warming, N fertilization, and their combination decreased foliar phosphorus (P) and magnesium (Mg) concentration of Picea asperata seedlings, but increased them in Pinus tabulaformis seedlings. Moreover, the combination of warming and N fertilization induced greater increments of amino acid, area-based N concentration and mass-based N concentration, manganese (Mn) and zinc (Zn), and further decreased P and calcium (Ca) concentration in Picea asperata seedlings. However, this phenomenon was not observed in Pinus tabulaformis seedlings. These results indicated that Picea asperata seedlings are more sensitive to the combination of warming and N fertilizer than Pinus tabulaformis seedlings.
Flame‐retardant and smoke‐suppressant properties of zinc borate and aluminum trihydrate‐filled rigid PVC

The effects of zinc borate (ZB), aluminum trihydrate (ATH), and their mixture on the flame-retardant and smoke-suppressant properties of poly(vinyl chloride) (PVC) as well as their mechanism for flame retardancy and smoke suppression were studied through the limiting oxygen index (LOI) test, smoke density test, TGA, GC–MS, and SEM. The results show that incorporation of a small amount of ZB, ATH, and their mixture can greatly increase the LOI of PVC and reduce the smoke density of PVC during combustion. The mixture of ZB with ATH has a good synergistic effect on the flame retardance and smoke suppression of PVC. TGA and GC–MS analyses results show that incorporation of a small amount of ZB, ATH, and their mixture greatly promotes the char formation of PVC and decreases the amount of hazardous gases such as benzene and toluene released in PVC during combustion. Their mechanism is also proposed. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 3119–3127, 2000
Organizational identification and communication: Employees' evaluations of internal communication and its effect on identification at different organizational levels

People often define themselves in terms of certain group memberships. These social identities are common in current life. People see themselves as being part of a country, gender, race, political movement, sports team or organization. In turn, these groups depend on their members to survive. Tajfel (1972) defined social identity as the individual's knowledge that he (or she) belongs to certain groups together with some emotional and value significance to him (or her) of the group membership. A specific form of group identification is called organizational identification (OI).
The Possibility of near Infrared Spectroscopy for Evaluation of Microbial Nitrogen Content of in Sacco Feed Residues and Duodenal Digesta of Sheep

This study aimed to estimate by near infrared (NIR) spectroscopy the microbial nitrogen content (MN) of feed residues from in sacco degradability trails and duodenal digesta of sheep. NIR spectra from 50 samples of duodenal digesta, and from in sacco residues—110 samples of alfalfa hay and 38 samples of maize silage were obtained using an NIRSystems 4250 spectrophotometer. The microbial nitrogen (MN) content of part of the alfalfa hay in sacco residues (78 samples) was calculated from the percentage of 15N enrichment compared to enrichment in the original samples; for the rest of the alfalfa samples and samples of maize silage residues were determined by diaminopimelic acid (DAPA) as a bacterial marker, and MN of duodenal digesta samples by the purine N (RNA equivalent) content as a microbial marker. The calibration equations were developed by modified least squares as the calibration method. The microbial content of all kinds of samples was accurately calibrated and cross-validated. A standard error of cross validation (SECV) of 0.418 g microbial N kg−1 DM, a coefficient of determination for the cross validation of 0.925 and a ratio of standard deviation of population and the SECV of 3.88 were obtained for the alfalfa 15N labelled hay residues. For maize silage residues, the corresponding values were 0.832, 0.938 and 3.90, and for duodenal digesta samples the values were 1.05, 0.962 and 5.19, respectively. Prediction of MN as percentage of total N of the samples gave approximately the same level of accuracy. For example, the SECV was 2.35% units, cross-validation R2 was 0.953, SD/SECV was 4.60 for alfalfa 15N labelled hay residues. Despite the different origin of the analysed samples (feed residues and duodenal digesta), the NIR spectroscopy determination of MN content of all samples was based on spectral data at very similar wavelengths. The study indicated that NIR spectroscopy has the potential to predict microbial nitrogen content and to distinguish MN from total N content of in sacco feed residues and duodenal digesta.
Laboratory evaluation of absorbents and additives on the fermentation quality of potato hash

This study was conducted to determine the ensiling potential of potato hash (PH) with poultry litter (PL) and hay as absorbents, and whey and molasses as additives. Mixtures of 800 g/kg PH and 200 g/kg of either PL or hay were produced and treated with no additive, whey and molasses. The experiment was conducted in a 2 absorbents × 3 additives factorial design. Mixtures were ensiled in 1.5 L anaerobic jars, and sampling was done on days 0, 4, 10, 20, 40, 60, and 90 for the determination of fermentation quality and nutritive value. Further, an aerobic stability test was done on day 90 by exposing silage to air for 5 days. Ensiling PH with hay compared to PL resulted in a better quality silage as indicated by (P < 0.05) improved fermentation characteristics and chemical composition. Although, the addition of PL significantly increased (P < 0.05) the crude protein (CP) and ash contents in PH silage, fermentation, and the aerobic stability of silage was poor and could influence animal performance negatively. It seems that whey and molasses were effective in improving the in vitro organic matter digestibility (IVOMD) and fermentation characteristics of PH. Further studies are needed to elucidate these effects on animal performance. Key words:
Composition of 15–85 nm particles in marine air

Abstract. The chemical composition of 15–85 nm diameter particles was measured at Mace Head, Ireland, during May 2011 using the TDCIMS (thermal desorption chemical ionization mass spectrometer). Measurable levels of chloride, sodium, and sulfate were present in essentially all collected samples of these particles at this coastal Atlantic site. Acetaldehyde and benzoic acid were also frequently detected. Concomitant particle hygroscopicity observations usually showed a sea-salt mode and a lower hygroscopicity mode with growth factors near to that of ammonium sulfate. There were many periods lasting from hours to about 2 days during which the 10–60 nm particle number increased dramatically in polar oceanic air. These periods were correlated with the presence of benzoic acid in the particles and an increase in the number of lower hygroscopicity mode particles. Very small (
Steric contributions to CO binding in heme proteins: a density functional analysis of FeCO vibrations and deformability

Non-local Density Functional Theory (DFT) is applied to the calculation of geometry and vibrational frequencies of FeII(porphine)(imidazole)(CO), a model for CO adducts of heme proteins. Bond distances and angles are in agreement with crystallographic data, and frequencies are correctly calculated for C–O and Fe–C stretching and for Fe–C-O bending. This last mode is actually the out-of-phase combination of Fe–C–O bending and Fe–C tilting coordinates, which are heavily mixed because of a large bend–tilt interaction force constant. The in-phase combination is predicted at a very low frequency, 73 cm-1, and to have a low infrared intensity; attempts to detect it in far-IR spectra via 13C18O isotope sensitivity have been unsuccessful. The stretch–bend interaction lowers the energy required for FeCO distortion. A soft potential may account for the wide range of crystallographically determined Fe–C–O displacements and orientations in myoglobin (Mb). The minimum energy path for displacement of the O atom from the heme normal was calculated by relaxing the structure while constraining only the O atom displacement from the heme normal. Energies of 0.2 to 3.5 kcal mol-1 are required for the range of reported displacement, 0.3–1.3 A. However, vibrational spectroscopy limits the allowable displacement to the low end of this range. The O atom displacement is computed via DFT to be 0.6 A for a 7 ° angle of the C–O stretching IR dipole relative to the heme normal, the maximum value compatible with IR polarization measurements on MbCO. FeCO distortion is predicted to diminish both νCO and νFeC, thereby producing deviations from the well-established backbonding correlation; the scatter of the data permits a maximum displacement of 0.5 A. This displacement would cost about 1.6 kcal mol-1 of steric energy. A small distortion energy is consistent with the CO affinity changes produced by mutations of the distal histidine residue in Mb. Taking the leucine mutant as reference, we estimate the 1.6 kcal mol-1 affinity loss in the wild-type protein to be the resultant of a 0.0–1.6 kcal steric inhibition, a 0.5 kcal mol-1 attraction of the distal histidine sidechain for the bound CO [weak H-bond], and a 0.5–2.1 kcal mol-1 attraction of the same side-chain for a water molecule in the deoxy protein. The observed 2.3 kcal mol-1O2 affinity increase in the wild-type protein relative to the leucine mutant then implies a 2.8–4.4 kcal mol-1 attraction of the histidine sidechain for bound O2, consistent with a substantial H-bond interaction with the distal histidine. Thus steric inhibition can account for only a minor fraction of the discrimination factor against CO and in favor of O2 which is produced by the heme–myoglobin interaction.
Efficient Methods For Arsenic Removal From Groundwater

Arsenic may be found in water that has fl owed through arsenic-rich rocks. Arsenic is a toxic, trace element that is ubiquitous in nature. It can easily be transported from the sediment to the surrounding pore-water. Severe health effects have been observed in populations drinking arsenic-rich water over long periods in countries worldwide. A 2007 study found that over 137 million people in more than 70 countries are probably affected by arsenic poisoning of drinking water. In groundwater, arsenic combines with oxygen to form inorganic pentavalent arsenate and trivalent arsenite. Most arsenic treatments fall into four process categories: ion exchange, membrane process, adsorption, or chemical precipitation. This study investigates the potential of removing arsenic from groundwater by using two process categories ‐ activated alumina and lime softening. Arsenic adsorption by commercially available activated alumina is surveyed and its effi ciency investigated. We have incorporated some of the valuable literature on arsenic remediation by adsorption. According to results of three activated alumina pilot studies, considering infl uence of adsorption time, temperature, pH, alumina quantity, arsenic concentration, and different alumina production resources, it has high effi ciency for arsenic removal. Adsorption isotherm for both species of arsenic (III and V) is compatible with both Freundlich and Langmuir models (correlation coeffi cient >0.93). The prevalent pH range for arsenate was between 6 and 8. Modifi ed activated alumina can remove arsenate at the infl uent pH of 8.1 ± 0.4 to below the maximum concentration level (MCL). The exhausted media passed the Toxicity Characteristic Leaching Procedure (TCLP) test with respect to arsenic. Lime softening operated within the optimum pH range of more than 10.5 is likely to provide a high percentage of arsenic removal (90%) for infl uent concentrations of up to 0.05 mg/L. It may be diffi cult to reduce consistently to 0.01 mg/L by lime softening alone. Systems using lime softening may require secondary treatment to meet that goal.
Pressure and temperature dependence of the self diffusion coefficient of water and oxygen-18 water

The self diffusion coefficients of water, DS(H216O), and of oxygen-18 water, DS(H218O), have been measured over the temperature range 277–333 K and to pressures of 300 MPa by the n.m. r. spin echo technique. The precision was ± 1%. The isotherms show the now familiar broad maximum below ≈ 308 K. The ratio of DS(H216O) to DS(H218O) is constant over the whole region studied and is equal to [m(H218O)/m(H216O)]½. Comparison of the self diffusion data with tracer data for HTO in water show the data to be consistent with a slightly greater coupling of translational and rotational motion of HTO relative to H2O in pure water at low pressures, i.e. the pressure dependence of DS is less marked for H2O, though the effect is rather small.
Emission of carbon dioxide influenced by nitrogen and water levels from soil incubated straw

An incubation study was carried out to investigate the influence of nitrogen rates to determine optimum C/N ratio under various moisture levels for straw decomposition and sequester carbon (C) in the soil. The aim was to observe straw carbon mineralization through measuring the amount of CO 2 evolution. A clay loam topsoil mixed with maize straw was supplied with four nitrogen rates (0.04, 0.08, 0.16, 0.32 g N/kg) using (NH 4 ) 2 SO 4 to adjust C/N ratios at 82, 42, 20, and 10. Soil moisture was maintained at 55%, 70%, 85%, and 100% of field capacity incubated at 25°C for 53 days. The experiment was set up with 16 treatments arranged in complete randomized design. Results showed that mixing of straw with soil increased 50% cumulative CO 2 -C compared to controls. Averagely, about 44% of added maize straw C was mineralized to CO 2 -C. Straw addition along with nitrogen and moisture had significant relationships (P < 0.05) to cumulative CO 2 -C, soil organic C and microbial biomass C. There was a highly signifi cant relationship (R 2 = 0.99) between CO 2 -C emission and incubation time.
Modeling Osmotic Salinity Effects on Yield Characteristics of Substrate-Grown Greenhouse Crops

Abstract In a series of experiments with different osmotic potentials in the root environment, various vegetables, and ornamentals were grown in a substrate system. The osmotic potential was varied by addition of nutrients. Yield characteristics of the crop were related to the osmotic potential of the nutrient solution. Experimental results were fitted to a discontinuous piecewise linear response model introduced by Maas and Hoffman in 1977 and this study extended the investigation by introducing a polynomial and an exponential test model. The correlation coefficients for the polynomial and exponential model were generally higher than with the piecewise linear model. The polynomial model has the drawback that calculation of the salinity yield decrease (SYD) value is not possible. Salinity threshold values could be calculated with all models tested. The average values did not show great differences and the EC values found were 2.4, 2.1, and 2.2 dS m−1 for the polynomial, exponential, and peace wise linear model, respectively. It is argued that the exponential equations showed the closest relationships between the EC in the root environment and the yield characteristics of the crops. Fifth order polynomial equations yielded at least equal or even higher correlation coefficients, but these equations are very responsive to accidental positions of observations. The traditional discontinuous linear fitting gave reasonable results, but only when experimental observations below the threshold value were selected and discarded. This undermines the power of this model, because exclusion of observations is always arbitrary. Furthermore, a discontinuous relationship between crop yield and EC in the root environment is not likely, because yield response is of biological nature. Nevertheless, when the number of observations is not sufficient for the quantification of the exponential equation, mostly reasonable estimations of the salinity parameters can be obtained with the Maas and Hoffman model.
Size and Shape of Calcium Alginate Beads Produced by Extrusion Dripping

Alginate hydrogel beads are widely used as an encapsulation medium for biomedical, bioprocessing, and pharmaceutical applications. The size and shape of the beads are often critically controlled since in many usages the beads are monodisperse in size and spherical in shape. Extrusion dripping is a well-known method to produce alginate beads. Nevertheless, the production of beads of desired size and spherical shape is often achieved based on one's experience or trial and error. An overview is provided on alginate properties, formulation and preparation of alginate and gelling solutions, production conditions, and post-production treatment that may influence the bead size and shape. Various methods of bead size and shape measurement are also discussed.
On the Porod law

The Porod law states that i(h), the intensity of X-radiation scattered by an ideal multiphase noncrystalline system, for `large' momentum transfer values (≡ h) approaches lh−4 and that l is linearly related to the interphase surface areas. A more general expression is obtained which relates the value of the correlation-function derivative at the origin to the integral of the discontinuity of the electron density fluctuation along the discontinuity surface. Debye's assumption, by which the continuous electron density of the sample is approximated by a discrete-valued one, is critically discussed. The validity of the approximation results in the presence of a Porod plateau [h4i(h) = constant]. The momentum transfer range where the plateau is observed is related to the scale of lengths where the sharp-boundary idealization remains essentially unchanged. It is argued that the scattered intensity can show more than one Porod plateau and some examples of correlation functions with this behaviour are reported. The problem of the background subtraction is discussed and the corresponding coefficients are related to the electron densities relevant to the real and to the associated sharp-boundary sample.
N-dimensional diamond, sodalite and rare sphere packings

The diamond, lonsdaleite and sodalite structures are generalized to N dimensions and described. Ring counts and coordination sequences for the N + 1-connected nets are given for N ≤ 6. Simple analytic expressions are given for coordination sequences for diamonds, sodalites and the primitive hypercubic lattice. Replacing the vertices of diamonds and sodalites by regular simplices produces rare (open) stable sphere packings; general expressions for the density of these are given.
The kinetics of package life. III. The isotherm

Published equations for the sorption isotherms of hygroscopic materials cannot be used in solving the Package Life equation, but it has been found empirically that Pearson's typo XII Frequency curve can be fitted to the isotherms of many non-crystalline commodities. Approximate solutions of the equation for the shelf-life of water-sensitive packages are derived. Separate equations are derived for absorption and desorption: the agreement of each with results observed in exposure trials is demonstrated.