Miracle-dz/UniFAR-FTUs huggingface dataset:
Surface effects on the magnetic behaviour of nanoparticles with core/shell morphology

We study the influence of the surface on the hysteresis behaviour of nanoparticles with core/shell morphology at an atomic level. We use a model that explicitly takes into account the dynamics of the core, interface and surface regions using the Metropolis Monte Carlo simulation algorithm. The presence of uncompensated spins (Nu) and the surface spins' canting strongly influence the magnetic response of antiferromagnetic nanoparticles. The strength of the surface anisotropy in this case determines the behaviour of the temperature dependence of the coercive field. In ferrimagnetic nanoparticles the magnetization and coercivity depend on the details of the surface.
Short-range order and thermal stability in amorphous alloys

Amorphous alloys of the types Zr1-xNix, Zr1-xCox, Zr1-xFex and Zr1-xCux were prepared by melt-spinning and studied by means of differential scanning calorimetry and X-ray diffraction. The crystallisation temperatures (Tx) and the activation energies for crystallisation ( Delta E) were determined. The former values were found to vary only slightly with concentration while the latter show a marked concentration dependence, which is particularly pronounced in Zr1-xNix. The occurrence of compositional short-range ordering (CSRO) in amorphous systems is discussed with respect to its consequences for the hole model proposed earlier. It is shown that the predictions of the hole model are only slightly affected by the occurrence of CSRO, owing to a gross cancellation of the effects of a decreasing hole formation enthalpy and decreasing configuration entropy. The relatively strong temperature dependence of the configurational entropy expected for alloy compositions with strong CSRO leads to an increase in the experimental values of the apparent activation energies. From the concentration dependence of the experimental activation energies indications can be obtained about the concentration dependence of CSRO. It appears that the regions with a maximum CSRO do not, in general, correspond to the concentrations at which intermetallic compounds occur, nor do they correspond in all cases to regions located around the deepest eutectic composition.
Charge Recombination Kinetics in Dye-Sensitized Nanocrystalline Titanium Dioxide Films under Externally Applied Bias

The kinetics of charge recombination were determined following low intensity optical excitation of RuII(2,2‘-bipyridyl-4,4‘dicarboxylate)2(NCS)2 sensitized nanocrystalline TiO2 films as a function of externally applied bias voltage V. These kinetics were found to be multiexponential. The median time (t50%) for charge recombination was found to depend strongly upon bias voltage, reducing from t50% ∼ 200 ms for V = 0 V versus Ag/AgCl to < 30 ns for V ≤ −500 mV. This reduction in t50% was found to follow the equation t50% ∝ exp(qV/1.7kBT). These results are consistent with the charge recombination kinetics being strongly dependent upon the accumulation of electrons in intraband/conduction band states of the TiO2 film. For biases V ≤ −400 mV, the rate of charge recombination was found to exceed the rate of rereduction of the dye cation by an I-/I3- redox couple in solution.
The impact of consumer religiosity on consumer perceptions of risk

This brief provides the conceptual background of current research aiming to improve the understanding of the relationship between consumer religiosity and social and psychological risks associated with adopting new products and technologies. This project includes two main studies framed by Hunt-Vitell’s General Theory of Marketing Ethics and Theory of Moral Potency. Using scenario based experimental 2x2 design, two research questions will be answered upon the completion of the project: what is the nature of the relationship between consumer religiosity and perceptions of psychological and social risk? What is the role of moral potency in the relationship between consumer religiosity perception of psychological and social risk?
Cyanophenyloximes: Reliable and Versatile Tools for Hydrogen-Bond Directed Supramolecular Synthesis of Cocrystals

A systematic structural and spectroscopic examination of the products resulting from cocrystallization reactions between three types of phenyloximes R−CN−OH (where R = H, Me, or CN) and a series of N-heterocyclic hydrogen-bond acceptors demonstrates that the acidity of the oxime -OH hydrogen-bond donor is crucial to the efficacy of the supramolecular assembly process. Cyanophenyloximes are comparable to carboxylic acids, in terms of success rate, whereas the significantly less acidic CH3- and H-substituted analogues are not effective at generating cocrystals despite close similarities in steric and geometric parameters. The importance and validity of using experimental pKa values and calculated electrostatic potential surfaces as a basis for predicting the supramolecular yield of an O−H···N interaction for driving the formation of cocrystals (within a functional group class) is unambiguously established, and six new crystal structures of cocrystals assembled using oxime···heterocycle-based hydrogen bonds .
Morphology and dissolution processes of metal sulfide minerals observed with the electrochemical scanning tunneling microscope

We report the use of a novel electrochemical scanning tunneling microscope (STM) in the study of surface topography and dissolution phenomena on naturally occurring metal sulfide minerals. Real time dissolution studies of galena in sulfate solution showed that at pH=2.7, the step edges are oriented with outward normal vectors parallel to 〈110〉. Atomic resolution images obtained in acidic perchlorate solution showed single vacancy sites, demonstrating the ability of the STM to resolve individual atomic species under electrolyte solutions. A novel syringe pump system was used to directly determine the effect of chloride ions on the surface structure at the onset of the adsorption process. STM images show the chloride ion produces small pits in the outermost layer of the surface. These observations underscore the importance of anionic species and their effects on the surface topography and dissolution rates. Initial investigations on pyrite and covellite suggest a potentially wide application to metal sulfid.
Chronic Tennis Elbow Treated by Platelet-Rich Plasma Versus Steroid Injections: A Comparative Study

Background: Painful elbow joint over the lateral epicondyle especially with resisted wrist extension are common signs of lateral epicondyle tendinopathy, also called tennis elbow. Objective: To evaluate the clinical outcome of local platelet rich plasma (PRP) injection in patients with chronic tennis elbow compared with a steroid (Depomedrol 40 mg) injection. Methods: A total of 88 patients with chronic tennis elbow were treated at Al-Kindy Teaching Hospital and private clinics. All patients had chronic pain for about 24 weeks or more and had failed first line treatment. The patients dividing into two groups, Group A injected with PRP (n = 44), and group B injected with depomedrol 40 mg (n = 44). A good clinical result was demarcated as 25% or more progress on the visual analog scale for pain. All patients followed for 6 months in both group for clinical successful result. Results: At three months (n = 44), in group A reported a perfection of 58.2% in their pain scores while 49.3% in the group B (N = 44). At 6 months follow up, the group A informed a perfection of 74.3% in their pain scores while 58.4 % in the group B. The local elbow tenderness recording at three months was 37.4% in the group A, while in the group B was 48.4%. At six months, 16.1% versus 30.2% recounted major elbow tenderness (P = .009) in groups (A and B) respectively. The clinical improvement rates at three months revealed no changes between both groups while it showed more significant clinically changes in group A ( 87.1%) than in group B (70.1 %) with P value = 0.008 after six months follow up. Conclusion: No important changes were found at 3 months in both groups, but at 6months, clinical significant perfections in patients treated with PRP group (group A)
Antioxidants in soil organic matter and in associated plant materials

The presence of antioxidants in soil could have a significant effect on the dynamics of soil organic matter. In this paper we report some preliminary experiments, which demonstrate that antioxidants can be extracted from soils and that the quantities vary from soil to soil. Extraction with 1.0 m NaOH was effective, and this was then used on a range of mineral and organic soils, and the antioxidant capacity of the resulting extracts was measured. The antioxidant capacities obtained were positively correlated with soil carbon contents and with the dissolved organic carbon contents of the extracts. Expressing the data per mass of soil carbon showed that the antioxidants generally decreased with depth in the soil profile, suggesting that they were subject to degradation during humification. In a follow‐up study, soil, litter and fresh plant samples were collected from 15 sites with a wide variety of vegetation types and analysed for their antioxidant capacities. The aim was to show that the antioxidant capacities in the soils were related to the antioxidant capacities of the fresh plant material and/or litter above. The antioxidant capacities of the soil samples were less than those in either fresh material or litter. While there was a significant positive relationship between the antioxidant capacities of fresh material and litter, no relationship existed between the antioxidant capacities of the soils and those of either fresh material or litter.
Mechanochemical synthesis of hydroxyapatite from calcium oxide and brushite

Fine hydroxyapatite (HA) powders were prepared by mechanically activating a mixture of calcium oxide and brushite powders in a high-energy shaker mill. A defective HA phase was formed when the starting powder mixture was activated for ≤20 h. When the mixture was calcined at 800°C, it was converted to β-tricalcium phosphate. In contrast, a nanocrystalline HA phase was formed when the mechanical activation was extended to 30 h. The material was transformed to a HA compound (Ca 10 (PO 4 ) 6 (OH) 2 ) of high crystallinity when it was calcined at 800°C.
Interactions of the trimethyltin(IV) cation with carboxylic acids, amino acids, and related ligands

The interactions of the trimethyltin(IV) cation, [Sn(CH3)3(H2O)2]+, with water, acetic, oxalic, malonic, succinic, tartaric, and citric acids, 4,4,4-trifluoro-1-(2-thienyl)butane-1,3-dione, pyridine, 2,2′-bipyridyl, pentane-2,4-dione, glycine, aspartic acid, histidine, 2-aminoethanethiol, cysteine, 2-mercaptoethanol, penicillamine, mercaptosuccinic acid, British Anti Lewisite (2,3-dimer-captopropan-1-ol), glutathione, orthophosphate, adenosine5′-monophosphate, inosine 5′-monophosphate, and pyrophosphate were investigated at 25 °C and ionic strength 0.3 mol dm–3(NaClO4) using the potentiometric technique. The proton formation constants of the ligands have been determined and the compositions and log β values of the complexes formed with the trimethyltin(IV) cation are also reported.
Synthesis of Graphene and Its Applications: A Review

Graphene, one-atom-thick planar sheet of carbon atoms densely packed in a honeycomb crystal lattice, has grabbed appreciable attention due to its exceptional electronic and optoelectronic properties. The reported properties and applications of this two-dimensional form of carbon structure have opened up new opportunities for the future devices and systems. Although graphene is known as one of the best electronic materials, synthesizing single sheet of graphene has been less explored. This review article aims to present an overview of the advancement of research in graphene, in the area of synthesis, properties and applications, such as field emission, sensors, electronics, and energy. Wherever applicable, the limitations of present knowledgebase and future research directions have also been highlighted.
Temperature dependence of three-point correlation functions of viscous liquids: the case of glycerol

What causes the dramatic slowing down of flow and relaxation that leads to glass formation in liquids as temperature decreases is hardly understood so far and is the subject of intensive research work. It is tempting to ascribe the strong temperature dependence of the dynamics, irrespective of molecular details, to a collective or cooperative behavior characterized by a length scale that grows as one approaches the glass transition. To access this length experimentally, we use the recently introduced three-point dynamic susceptibility, from which the number of molecules dynamically correlated during the structural relaxation, Ncorr, can be extracted. The three-point functions are related to the sensitivity of the averaged two-time dynamics to external control parameters, such as temperature and density. We studied Ncorr values in an important temperature range for a large number of liquids, and found that it systematically grows when approaching the glass transition. Here we specially emphasize the case of glycerol for which we combined dielectric and neutron spin echo spectroscopy to cover more than 16 decades in relaxation time.
The Notion of a DNA Minimal Cell: A General Discourse and Some Guidelines for an Experimental Approach

The staggering complexity of even the simplest living microorganisms on Earth elicits the question of whether such complexity is really necessary for life, or whether, instead, the basic functions of cellular life (homeostasis, reproduction, and evolution) can be, in principle, expressed by much simpler unicellular entities that contain only a few dozen genes. This suggests the notion of a minimal cell, i.e., the (potential) cell having the minimal sufficient molecular components to be defined as alive. The conceptual and practical implementation of such minimal cell(s) for our understanding of the notion of life, and also for possible biotechnological applications, is discussed here.
RAMAN SPECTRA OF CHONDRODITE AT VARIOUS TEMPERATURES

The effect of temperature on the Raman spectra of natural and synthetic chondrodite was investigated over the range 81 to 873 K at atmospheric pressure. All samples remained intact up to 873 K. This high-temperature stability is unusual, and contrasts with the behaviour of all other synthetic dense hydrous magnesium silicates which have, so far, been found to dehydrate at temperatures below 873 K at atmospheric pressure. Also, unlike the other dense hydrous magnesium silicates, the Raman-active OH-stretching bands of both natural and synthetic chondrodite were observed to decrease in wavenumber with increasing temperature. The negative temperature dependence of these vibrations suggests that there is a rather open environment around the OH bonds. All the Raman-active modes below 1000 cm−1 (except the 571 cm−1 band in synthetic, F-free, chondrodite) have a negative temperature dependence in accord with most other silicates. The temperature data, combined with published high-pressure data, were also used to determine the intrinsic anharmonicity of the Raman-active modes. Synthetic chondrodite was found to have smaller intrinsic anharmonic parameters (ai) than natural chondrodite. Comparison of the OH-stretching modes with the internal modes of synthetic chondrodite showed that they were similar but had opposite behaviour, while the internal modes of natural chondrodite were found to have much larger ai parameters. The modes at 931 and 966 cm−1 in natural chondrodite had the highest levels of intrinsic anharmonicity indicating that they may arise from SiOH vibrations rather than SiO4 vibrations. The larger temperature dependence of the Raman-active modes and the higher intrinsic anharmonicity of natural chondrodite indicate that the presence of fluorine atoms has a strong influence on the vibrational properties of chondrodite and the OH vibrations in particular. Copyright © 1999 John Wiley & Sons, Ltd.
The velocity of sound with derived state properties in helium at −175 to 150 °C with pressure to 150 atm

The velocity of sound was determined in helium on 14 equally spaced isotherms from −175 to 150 °C and at pressures from 10 to 150 atm. The results were correlated with an abbreviated perturbation equation of state which employs both the Lennard‐Jones (n,6) and the exponential repulsion potentials. Six parameters in the equation of state were adjusted to fit the velocity data within the experimental precision of about 0.001%. The derived results reliably predict literature (P,V,T) values and other velocity‐of‐sound data for pressures as high as 7000 atm and for temperatures from −223 to 577 °C. A value of the gas constant was derived, R=8314.79±0.35 J K−1⋅kmol−1, which is statistically consistent with the accepted value. The results also support a recent gas thermometry result that indicates the 1968 temperature scale may be in error by 0.012 K at −183 °C.
Dispersion and Absorption in Dielectrics II. Direct Current Characteristics

In the first paper of this series [J. Chem. Phys. 9, 341 (1941)], it was shown that the complex dielectric constant, e*, of many liquid and solid dielectrics is given by a single very general formula e*=e∞+(e0−e∞)/[1+(iωτ0)1−α]. In this equation e0 and e∞ are the ``static'' and ``infinite frequency'' dielectric constants, ω = 2π times the frequency, τ0 is a generalized relaxation time and α is a constant, 0 < α < 1. The transient current as a function of the time, t, after application of a unit constant potential difference has been calculated from this expression in series form. For times much less than τ0, the time dependence is of the form (t/τ0)−α, and for times much greater than τ0, it is of the form (t/τ0)−(2—α). The transition between these extremes occurs for the range in which t is comparable with τ0. The total absorption charge, which is the integral of the exact expression, is always finite. Although many transient data for dielectrics are of the predicted form, none have been taken over a suff.
The interior interfaces of a semiconductor/metal nanocomposite and their influence on its physical properties

A semiconductor/metal hybrid system with silicon as base material and embedded metal nanostructures is fabricated in two steps by anodizing the silicon substrate in an aqueous hydrofluoric acid solution and a subsequent electrodeposition process. The achieved self-assembled nanoscopic hybrid system consists of a quasi-regular 3-dimensional arrangement of metal nanostructures embedded within the pores of the silicon matrix. The used metals are Ni, Co and their alloys, whereas mainly Ni is considered in the following. In such a hybrid system the interface between metal and silicon nanostructures is of interest in correlation with the properties of the material and can be influenced by different fabrication conditions. If the matrices are aged in ambient air before filling with a metal the inner surface of the porous silicon template offers a native SiOx layer due to the oxidation of the hydrogen terminated surface of the pore-walls. Using as-etched samples for deposition of the metal into the pores leads to the formation of a more complex interface during the cathodic deposition procedure which is observed by FTIR-spectroscopy. Knowledge about the composition and the formation of the interior surface of the porous silicon matrix as well as the interface between semiconductor and metal is necessary on the one hand for interpretation of the gained experimental results and on the other hand to figure out possible applications of the fabricated hybrid system. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Nonionic bilayers in dilute solutions: effect of additives

We have investigated the effect of alcohols and other additives on the binary phase diagram wate-C 12 E 5 . In particular, we have located the dilute lamellar L α phase and the L 3 phase as function of additive concentration on the temperature scale. In the L α phase undulations stabilize bilayer membranes at distances on the order of hundred nanometers. We have determined their repeat distance quantitatively by light scattering. By addition of medium-chain alcohols, the projected area of the undulating membranes was found to increase drastically
Synthesis and mesomorphic properties of symmetric tetradentate Schiff bases based on azo-containing salicylaldimines and their copper(II) complexes

Two new tetradentate Schiff bases, in which two identical aromatic bent core mesogenic units containing phenylazo are connected via a 1,2-phenylene spacer, N,N′-di-(5-(4-alkoxyphenyl)azo)-salicylidene-1,2-phenylene diimine (alkoxy = decyloxy, dodecyloxy), and their copper(II) complexes were synthesized and studied for their mesomorphic character. The ligands were prepared by the condensation of 5-((4-alkoxyphenyl)azo)salicylaldehydes with 1,2-phenylene diamine. The ligands and their copper complexes have been characterized by IR, 1H-NMR, electronic spectra, mass spectroscopy, and elemental analyses. The copper complexes were also studied by magnetic moment and electrical conductance measurements. The liquid crystalline properties of the ligands and the related copper complexes were investigated by differential scanning calorimetry (DSC) and by using a polarizing microscope equipped with a heating and cooling stage. None of the free ligands exhibit liquid crystalline behavior but the copper complexes display an enantiotropic smectic C mesophase.
Aromatic Triazoles as Corrosion Inhibitors for Mild Steel in Acidic Environments

Abstract 3-hydroxyphenyl-4-phenyl-5-mercapto-1,2,4,triazole (HPMT); 3-aminophenyl-4-phenyl-5-mercapto-1,2,4,triazole (APMT); 3,4-diphenyl-5-mercapto-1,2,4-triazole (DPMT); and 3-cinnamyl-4-phenyl-5-mercapto-1,2,4,triazole (CPMT) were synthesized in the laboratory, and their influence on the inhibition of corrosion of mild steel in 1 N hydrochloric acid (HCl) and 1 N sulfuric acid (H2SO4) was investigated by weight loss and potentiodynamic polarization techniques. The inhibition efficiency of these compounds was found to vary with concentration, temperature, and immersion time. Good inhibition efficiency was evidenced in both acid solutions. The adsorption of these compounds on the steel surface for both acids was found to obey Temkin's adsorption isotherm. The potentiodynamic polarization data showed that the compounds studied were filming (adsorption) inhibitors.
Effects of Alkaline Extraction on Micro/Nano Particles of Phyllostachys pubescens Biomass

Bamboo forest was a dominantly ecological and sustainable economic recources. However, bamboo extractives and hemicellulose were nearly complete dissolved out in preparation of the fiber, this would result in more serious water pollution and meanwhile bring a great waste of biological resources. Thereby, In order to obtain the way to lower the negative impact of the extractives and hemicellulose, the Phyllostachys pubescens biomass was treated in alkaline solutions at room temperature and the extractives obtained was analyzed by SIZER basen on the full-factor method. The results were following as: (1) Sort of alkaline and concentration of alkaline had a significant influence on the leaching rate of particles at 0.01 level. And the optimal concentrations of KOH, NaOH, LiOH were 16.0%, 17.5% and 17.5% at 25°С, respectively. (2) Pretreatment, extraction time and sort of alkaline had no influence on the leaching rate of particles. But the benzene/ethanol pretreatment was valuable and necessary. when 16% NaOH and 17.5% KOH were used, the optimal extraction time were all 16h to untested and tested samples.