Miracle-dz/UniFAR-FTUs huggingface dataset:
Crystal packing and physical properties of pyridinium tetrabromocuprate(II) complexes assembled ia hydrogen bonds and aromatic stacking interactions

The compounds (pyH)2[CuBr4] (1) (pyH = pyridinium) and (n-MepyH)2[CuBr4] [n-MepyH = n-methylpyridinium; n = 2 (2), 3 (3) and 4 (4)] have been synthesised from ethanolic solutions containing CuBr2, HBr and the aromatic base in a 1 : 2 : 2 molar ratio. The compounds have been characterised by elemental analysis, IR, UV/VIS and EPR spectroscopies, thermal analysis, variable-temperature magnetic susceptibility measurements and single-crystal X-ray diffraction. In all four crystal structures, the tetrabromocuprate(II) anion is connected to two organic cations through N–H···Br hydrogen bonds to form cation–anion–cation molecular units, which are held together by means of offset face-to-face interactions between the aromatic rings to give one-dimensional chains (1, 2 and 4) or a dimeric entity (3). The hydrogen bond and the aromatic stacking interactions are strongly influenced by the position of the methyl group in the pyridinic ring of the cations. The delicate balance between these non-covalent intermolecular forces, together with the electrostatic interactions, ultimately determines the structure and, as a consequence, the physical properties (thermal stability, density and magnetic behaviour) of the compounds. Magnetic susceptibility measurements of powdered samples show that the compounds exhibit weak antiferro- (1, 2, 4) or ferromagnetic (3) magnetic couplings between the copper centres transmitted through the hydrogen bond and the π-stacking interactions. Compound 1 shows a reversible phase transition at 65 °C with a thermal hysteresis of 4 K.
Chemokine-glycosaminoglycan binding. SPECIFICITY FOR CCR2 LIGAND BINDING TO HIGHLY SULFATED OLIGOSACCHARIDES USING FTICR MASS SPECTROMETRY. VOLUME 280 (2005) PAGES 32200-32208

Glycosaminoglycans (GAGs) have recently been demonstrated to be required for the in vivo activity of several chemokines. Mini-mally, the interaction is thought to provide a mechanism for reten-tion at the site of secretion and the formation of chemokine gradients that provide directional cues for receptor bearing cells, particularly in the presence of shear forces. Thus, a key issue will be to determine the sequence and structure of the GAGs that bind to specificchemokines.Herein,wedescribeamassspectrometryassay that was developed to detect protein-oligosaccharide noncovalent complexes, in this case chemokine-GAG interactions, and to select for high affinity GAGs. The process is facilitated by the ability of electrospray ionization to transfer the intact noncovalent complexes from solution into the gas phase. The elemental composition aswellasthebindingstoichiometrycanbecalculatedfromthemass of the complex. Ligands of the chemokine receptor, CCR2 (MCP-1/ CCL2, MCP-2/CCL8, MCP-3/CCL7, MCP-4/CCL13, and Eotaxin/ CCL11), and the CCR10 ligand CTACK/CCL27 were screened againstasmall,highlysulfated,heparinoligosaccharidelibrarywith
The extrapolation of the vapour—liquid equilibrium curves of pure fluids in the isothermal Gibbs ensemble

A powerful extrapolation scheme is proposed to determine the vapour-liquid equilibrium (VLE) curves of pure molecular fluids over a finite temperature range by performing a single Gibbs ensemble Monte Carlo (GEMC) simulation. The VLE curves of the various thermodynamic quantities are extrapolated as functions of the temperature by second-order Taylor series. The coefficients of the Taylor series, which are the temperature derivatives of these quantities along the VLE curves, can be calculated from a single GEMC simulation using Clapeyron-like equations and fluctuation formulas containing double or triple correlations. It is shown that the application of a Padé approximant considerably widens the temperature range where the extrapolation is accurate. The efficiency of the method is demonstrated by applying it on the Lennard-Jones fluid and a three-site model of carbon dioxide. The procedure is found to be a very useful tool that is able to reproduce the VLE curves over a considerable temperature range. The procedure makes it possible to calculate the saturation heat capacity from fluctuation formulas.
Oxidation of Aniline with Silver Nitrate Accelerated by p-Phenylenediamine: A New Route to Conducting Composites

The reaction between two nonconducting compounds, aniline and silver nitrate, yields a composite of two conducting products, PANI and silver. While the oxidation of aniline with silver nitrate is slow and takes over several months, the addition of a small amount of p-phenylenediamine, 1 mol % relative to aniline, shortens the reaction time to a few hours and, with higher concentrations of p-phenylenediamine, even to tens of minutes. Nonconducting aniline oligomers, however, are also present in the oxidation products as a rule. The chemistry of individual oxidation pathways is discussed. Higher concentrations of p-phenylenediamine in the reaction mixture with aniline give rise to copolymers, poly[aniline-co-(p-phenylenediamine)]s, and their composites with metallic silver. p-Phenylenediamine alone can similarly be oxidized with silver nitrate to poly(p-phenylenediamine) composite with silver. Silver is present in the composites both as nanoparticles of ∼50 nm size and as larger objects. The composites have.
EXTRACTION OF CAROTENOPROTEIN FROM BLACK TIGER SHRIMP SHELLS WITH THE AID OF BLUEFISH TRYPSIN

ABSTRACT The effect of bluefish (Pomatomus saltatrix) trypsin on the recovery and characteristics of carotenoprotein from black tiger shrimp (Penaeus monodon) shells was investigated. Trypsin concentration and reaction time both affected the hydrolysis and the recovery of carotenoproteins (P < 0.05). The recovery of carotenoproteins from shrimp shells was maximized by the hydrolysis of shrimp shells using 1.2 trypsin units/g shrimp shells for 1 h at 25C. Freeze-dried carotenoprotein recovered contained 70.20% protein, 19.76% lipid, 6.57% ash, 1.50% chitin, and 87.91 µg total astaxanthin/g sample, indicating a substantial reduction in the levels of antinutrients associated with shrimp waste, while enriching the product in carotenoid pigments and valuable essential nutrients (proteins and lipids). Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of the recovered carotenoprotein revealed that protein with molecular weight of 45 kDa was the major constituent. When hydrolytic activities of bluefish and bovine trypsins toward carotenoproteins in black tiger shrimp shells were compared, the recovery efficacy of protein and pigment by bluefish trypsin was similar to that achieved by trypsin from bovine pancreas. Therefore, bluefish trypsin could be used as an alternative cheap proteinase for extraction of carotenoproteins from black tiger shrimp shells. PRACTICAL APPLICATIONS Carotenoproteins from black tiger shells, the byproduct of shrimp processing, can be recovered with the aid of fish trypsin. This product can be used for both food and feed applications. Additionally, the fish trypsin can be used instead of bovine trypsin. As a whole, the utilization of fish and shellfish processing wastes can be maximized.
Low divergence edge‐emitting laser with asymmetric waveguide based on one‐dimensional photonic crystal

We report on the lasers with a waveguide designed as a one-dimensional photonic band crystal with an irregularity (defect) to achieve low-divergence emission. Small vertical divergence less than 10o, high differential efficiency of 85% and CW output power of 1.8 W (10.6 W pulsed) have been obtained. For lasers with increased modal spot size very small vertical divergence emitting angle of 4.8o has been realized. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Nitrogen fertilization of strawberries: Nmin, leaf dry matter, and leaf sap analyses as control methods

Abstract In a three‐year survey several control methods of nitrogen (N) supply in strawberry were investigated. It was found that Nmin analysis could be used as a measurement of control from the beginning of the season, indicating the need of additional N supply. Leaf dry matter analysis, taken during flowering, could be used as an indicator thus making it possible to make corrections within the season, if needed. When leaf dry matter analysis was compared to leaf sap analysis, correlations were evident for the majority of nutrients, N being an important exception. It was concluded that the use of Nmin‐ and leaf dry matter analyses combined might make corrections in N fertilization within the same year possible.
Modifications of cellulose using ionic liquids

This project was focused on the modi cations of cellulose using ionic liquids. Cellulose is the most highly abundant natural biopolymer on earth. However the utilisation of cellulose requires chemical modi cation or physical dissolution in a suitable solvent. Recently ionic liquids have become the solvent of choice for cellulose and other biopolymers. This is because of their unique solvency power and the desirable properties such as nonammability, thermal stability, and recyclability. The use of cellulose/ionic liquid combinations not only supports the green chemistry concept but also helps in the development of sustainable resources which could be used as replacement for petroleum feed stocks. In this research ionic liquids were used to dissolve cellulose. The ionic liquids used in this study were 1-butyl-3-methylimidazolium chloride, 1-allyl-3methylimidazolium chloride, and 1-ethyl-3-methylimidazolium acetate. Rheology, heating FTIR and Raman studies were performed with ionic liquids and cellulose solutions to understand the properties of ionic liquids and cellulose solutions. The spectra from the heating studies were subjected to two dimensional correlation analyses. The rheology studies suggest that the ionic liquids themselves exist in two states, liquid state and a network state and the two dimensional analyses of the heating spectra reveals that the hydrogen bonding between C2H of the imidazolium ring, anion and moisture was responsible for this network formation. The cellulose was regenerated or fractionally precipitated from solutions using water, ethanol or acetonitrile as non-solvent. This investigation suggests that protic solvents like water and ethanol are good solvents for gel formation and acetonitrile is a desirable solvent for fractionation. The regenerated and fractionated cellulose samples were characterised by SEM, NMR, FTIR, XRD, DSC, TGA and SEC-MALLS analyses. Nano/sub-micron sized particles of cellulose were produced iii from the fractionation of cellulose from solutions in 1-ethyl-3-methylimidazolium acetate. SEC-MALLS data indicate that fractionation according to molecular weight is possible with dilute solutions in ionic liquids. It was also observed that samples regenerated from solutions in 1-ethyl-3-methylimidazolium acetate were more ordered than the samples regenerated from chloride containing ionic liquids. These preliminary results show that the use of ionic liquids in the processing of cellulose has the potential to have many possible applications.
Ion bombardment in rf plasmas

Ion bombardment energy and angle distributions have been measured in an argon plasma. The measured ion angle distribution at 10 mTorr shows that 30% of the ions have incident angles greater than 10° from the surface normal. However, ions with large incident angles have much lower energies than those incident perpendicular to the surface. At 500 mTorr a very large fraction of the ions have large incident angles, and the average energies of these ions are relatively independent of incident angle. Monte Carlo simulations of the sheath kinetics predict the trends shown in the experimental data for ion energy and angle distributions. Fine structure in the ion energy distribution was observed below 50 mTorr and is shown to be caused by charge‐exchange collisions in the sheath. The average ion energy in a symmetric parallel plate system is linearly related to the voltage applied across the electrodes for measured plasma pressures up to 500 mTorr.
Displacement washing of kraft pulp cooked from a blend of hardwoods

The aim of this work was to investigate the displacement washing of kraft pulp manufactured from a blend of hardwoods. The experiments were carried out in a laboratory washing cell. In order to characterise the pulp fibres, the degree of freeness, kappa number, fibre length, as well as the specific volume and specific surface of swollen fibres were determined. The displacement washing process was described by displacement washing curves recorded for alkali lignin as a tracer. Mathematical treatment of the washing curves, obtained as a response to the step input signal, gave the Péclet number characterising the displacement of alkali lignin from the pulp pad. For detailed description of the displacement washing process, further parameters, such as the traditional wash yield, axial dispersion coefficient as well as the mean residence time and the space time were also evaluated. The results obtained for hardwood pulp were compared with those for softwood pulp published earlier. With respect to different chemical composition and morphological characteristics affecting both concentration of alkali lignin in mother liquor and physical properties of pulp pad, the displacement washing efficiency of hardwood pulp was found to be unambiguously greater in comparison with softwood pulp.
Solvent Extraction of U(VI) by Calix[6]arenes

Abstract This paper focuses on the solvent extraction of U(VI) traces by 1,3,5‐OMe‐2,4,6‐OCH2CONHOH‐p‐tert‐butylcalix[6]arene (LH3). The global extraction equation of U(VI) has been established. The complex formed in the organic phase is (UO2)(LH) with an apparent extraction constant equal to 7.1×10−5 M (I=0.04 M). Distribution data show that LH3 efficiently extracts U(VI) from NaNO3 media at pH 5 and that the stripping of U(VI) can be achieved in nitric acid solutions. Finally a comparison with previous results obtained with the 1,3,5‐OMe‐2,4,6‐OCH2COOH‐p‐tert‐butylcalix[6]arene (L′H3) shows that the hydroxamate groups are as efficient as the carboxylate ones for uranyl extraction.
Effects of added organic matter on iron and manganese redox systems in sediment

Abstract Addition of five types of organic matter to Lake Washington sediments resulted in release of high concentrations of iron, organic carbon, and manganese into the interstitial water, and caused an increase in observed sediment oxygen consumption rates. The depressed electrode potentials (Eh < —150 mV) that should accompany such reduction processes did not occur, indicating that Eh was being poised by redox systems present in the sediment. Iron redox systems [Fe(OH)3‐Fe2+, Fe3(OH)8‐Fe2+, and Fe(OH)3‐Fe3(OH)8] were shown to be poising the Eh of control sediments throughout 13 weeks of incubation and dominating the potential of several of the organically amended sediments following the first three weeks of incubation. Depression of calculated iron system Eo values relative to that of the control sediment early in the incubation appeared to be due to the decreased pH and non‐equilibrium conditions in the organic matter‐amended sediment during the first weeks of incubation. Manganese redox systems exert.
Drying Characteristics of Porous Materials in Superheated Steam Fluidized Bed under Reduced Pressure

The drying characteristics of porous materials immersed in a superheated steam fluidized bed under reduced pressure were examined. The effect of pressure in the drying chamber on the drying characteristics was compared with that of hot air fluidized bed drying.The sample temperature in drying is almost equal to the boiling point of water in the case of superheated steam fluidized bed drying, and the temperature is higher than that in the case of hot air fluidized bed drying. The sample temperature becomes lower as the pressure in the drying chamber decreases, since the boiling point of water decreases. The effect of the mass velocity of the drying gas is not significant when the fluidization state is sufficiently vigorous. As the pressure in the drying chamber decreases, the difference of drying characteristics between superheated steam fluidized bed drying and hot air fluidized bed drying becomes small.
Leucaena leucocephala Meal as Replacement to Soybean Meal in Growing Goat Diets

Eight goats of 7-8 months old and an average body weight (BW) of 20 ± 5.0 kg were used in double 4 × 4 Latin square design. The treatments were the four levels of leucaena meal replacement for soybean meal in concentrates at 0%, 25%, 50% and 75% of crude protein. The results showed that roughage intake (% BW and g/kgBW^(0.75)) increased linearly (P ＜ 0.01) with increasing levels of leucaena meal while total feed intake was not significantly different among dietary treatments. Similarly, dry matter, organic matter, neutral detergent fiber digestibility and ruminal ammonia nitrogen (NH3-N) were not significantly different among dietary treatments. However, crude protein digestibility, ruminal pH (6 hr after feeding), nitrogen (N) intake, N absorption, N retention and total volatile fatty acids increased quadratically (P ＜ 0.01) with the increasing levels of leucaena meals. It could be concluded that leucaena meal could replace up to 50% of soybean meal in the diet without any negative effect on feed intake, nutrient digestibility and rumen fermentation of meat goats.
Reactivity of electrogenerated free hydroxyl radicals and activation of dioxygen on boron-doped diamond electrodes

Synthetic boron-doped diamond (BDD) thin film is an electrode material with high chemical and dimensional stability, low background current and a very wide potential window of water stability. Upon anodic polarization, BDD generates hydroxyl radicals that mediate the oxidation processes in the vicinity of the electrode surface. These hydroxyl radials are assumed to be free, i.e., not adsorbed on the electrode surface. Hydroxyl radicals are formed on BDD during water discharge, which is the rate determining step of oxygen evolution reaction. Oxygen evolution on BDD occurs at a high overpotential (over 1 V) with respect to the thermodynamic potential for O2 formation (E0OER = 1.23 V vs. SHE), but very close to the thermodynamic potential of HO• formation (E0HO• = 2.38 V vs. SHE). In the presence of organics, the onset potential of HO• formation changes, which affects the current–potential curves. As a consequence, oxidation of most of organic compounds on BDD results in a shift of the current–potential curves toward lower potentials. An exception is acetic acid, which adsorbs on the electrode surface causing auto-inhibition of its oxidation (oxidation is shifted toward higher potentials). In general, however, oxidation of organics on BDD is a fast reaction, controlled by the mass transport of organics to the anode surface. In the presence of an organic compound, hydroxyl radicals initiate chain reactions resulting in involvement (activation) of molecular oxygen dissolved in aerated aqueous solution. Direct evidence for this process was found during oxidation of acetic acid solution saturated with isotopically labelled 18O2. As a result, C18O2 and C16O18O were evolved proving that molecular oxygen participates in the mineralization of acetic acid. This electrochemically induced activation process is probably initiated by organic free radicals (R•) formed during reaction between organic compounds and hydroxyl radicals. Organic free radicals react further with molecular oxygen to form peroxy radical (RO2•). Organic peroxy radicals are very reactive and can initiate subsequent chain reactions leading, via several possible intermediates, to complete oxidation of organic compound. In fact, similar mechanism has been reported in radiolysis (upon X-ray or γ-ray) of aqueous solutions of acetic acid. This non-faradaic enhancement of the electrooxidation processes opens the possibilities for designing a less energy consuming degradation of organic pollutants on BDD anodes.
Vitrification during the Isothermal Cure of Thermosets: Comparison of Theoretical Simulations with Temperature-Modulated DSC and Dielectric Analysis

Vitrification during the isothermal cure of a thermoset, which is monitored by dynamic techniques such as temperature-modulated differential scanning calorimetry (TMDSC) or dielectric analysis (DEA), is analyzed in terms of its dependence on frequency. A simulation was used to obtain the vitrification time as a function of frequency, considering it as the time when the (frequency-dependent) glass transition temperature, Tg, of the curing system reaches the cure temperature. Simulations were carried out at different cure temperatures. Other parameters, such as the exponents (reaction orders) in the Kamal equation, l in the DiBenedetto equation (controlling the dependence of Tg on the degree of cure), and the activation energy for the frequency dependence of Tg, were also considered. The results are compared with those obtained experimentally by a TMDSC technique at low frequencies and by DEA at high frequencies. From the simulations it is found that the vitrification time decreases nonlinearly with log(frequency) in the low frequency range but approaches a linear dependence at high frequencies, in agreement with experimental data.
Assessing the Moderating Relationship for Mobile Learning Apps: A study of students in college context

On the verge of information and technology advancement, mobile applications are used creatively in different areas such as learning, communication, networking, banking, entertainment, security etc. In the education, the mobile device has a variety of mobile learning apps to learn the basic concepts and to attain up to date information on different subjects such as marketing, HR, finance, mathematics, computer science, general knowledge etc. The current study was conducted to identify various factors affecting the usage of mobile apps among students for learning purpose. This study explored the impact of content quality, user-friendly and layout and graphic design of mobile apps on perceived self-performance among students in academics. The study also identified the moderating effect of mobile learner’s perceived motivation on perceived self-performance in academics. The study tried to find out the difference between gender (male and female) on using all the variables in the current study. Data was collected from students studying in private management institutions. The results were found positive based on the hypothetical model in the current study i.e., content quality, user-friendly, layout design, were taken as an independent variable and perceived self-performance was used as dependent variable and meanwhile the moderating role of perceived motivation was evaluated.
A facile synthesis of cysteine-ferrite magnetic nanoparticles for application in multicomponent reactions-a sustainable protocol

A facile, simple and environmentally friendly Fe3O4–cysteine MNP was synthesized without any additive or additional source of linkers. Fe3O4–cysteine MNPs were successfully used for the synthesis of β-amino carbonyl and hydroquinoline compounds, which were obtained in excellent yields via multicomponent reactions. Magnetic organocatalysts can be easily recovered by simple magnetic decantation and their catalytic activity remains unaltered after 9 consecutive cycles, making them environmentally friendly and widely applicable due to their efficiency, ease of handling, and cost effectiveness.