Ion Concentration Ratio Research Articles

핵연료 피복관 부식생성물 부착에 관한 Ni/Fe 이온 농도비의 영향

핵연료 피복관 부식생성물 부착에 관한 Ni/Fe 이온 농도비의 영향

Exploration of the fundamental equilibrium behaviour of calcium exchange with weak acid cation resins

This study evaluated the complexity of calcium ion exchange with sodium exchanged weak acid cation resin (DOW MAC-3). Exchange equilibria recorded for a range of different solution normalities revealed profiles which were represented by conventional “L” or “H” type isotherms at low values of equilibrium concentration (Ce) of calcium ions, plus a superimposed region of increasing calcium uptake was observed at high Ce values. The loading of calcium ions was determined to be ca. 53.5 to 58.7g/kg of resin when modelling only the sorption curve created at low Ce values, which exhibited a well-defined plateau. The calculated calcium ion loading capacity for DOW MAC-3 resin appeared to correlate with the manufacturer's recommendation. The phenomenon of super equivalent ion exchange (SEIX) was observed when the “driving force” for the exchange process was increased in excess of 2.25mmol calcium ions per gram of resin in the starting solution. This latter event was explained in terms of displacement of sodium ions from sodium hydroxide solution which remained in the resin bead following the initial conversion of the as supplied “H+” exchanged resin sites to the “Na+” version required for softening studies. Evidence for hydrolysis of a small fraction of the sites on the sodium exchanged resin surface was noted. The importance of carefully choosing experimental parameters was discussed especially in relation to application of the Langmuir–Vageler expression. This latter model which compared the ratio of the initial calcium ion concentration in solution to resin mass, versus final equilibrium loading of the calcium ions on the resin; was discovered to be an excellent means of identifying the progress of the calcium–sodium ion exchange process. Moreover, the Langmuir–Vageler model facilitated standardization of various calcium–sodium ion exchange experiments which allowed systematic experimental design.

Quantitative calibration and germanium SIMS depth profiling in Ge x Si1 − x /Si heterostructures

Methods for minimizing nonlinear matrix effects in the quantitative determination of germanium concentrations in GexSi1 − x layers by secondary ion mass spectrometry are discussed. The analysis conditions with positive SiCs+, GeCs+ and negative Ge−, Si− secondary ions produced during sputtering by cesium ions are used in the TOF.SIMS-5 setup with a time-of-flight mass analyzer. In contrast to published works for TOF.SIMS setups, the linear dependence of the ion-concentration ratio Ge−/Si− on x/(1 − x) is shown. Two new linear calibrations for the germanium concentration as a function of the cluster Ge2− secondary ion yield are proposed. The calibration factors are determined for all linear calibrations at various energies of sputtered cesium ions and Bi+ and probe Bi3+ ions. It is shown for the first time that the best depth resolution among the possible conditions of quantitative germanium depth profiling in GexSi1 − x/Si multilayer heterostructures is provided by the calibration mode using elemental Ge− and Si− negative secondary ions.

Breakthrough in Modeling of Electrodiffusion Processes: Continuation and Extensions of the Classical Work of Richard Buck

The first really successful numerical modeling of electrodiffusion problems was presented in 1978 in the important paper by Timothy Brumleve and Richard Buck [1]. Novelty of their approach consisted of fully implicit method, non-uniform grids, and two different types of finite differences (one for concentrations and second for fluxes) allowed to “create an efficient computer algorithm which permits treatment of multi-ion systems, thick or thin cells (membranes), and interfacial kinetics” [1].In spite of the rapid increase of computational power at the time this approach was not immediately widely recognized and followed by the electrochemical community. However, it has changed to some degree at the beginning of 21stcentury e.g. [2-5,7,8]. But still the majority of present numerical modeling of electrodiffusion processes, e.g. interpretations of ion-sensor response, determination of transient behavior of a system to electrical and chemical perturbations (electrochemical impedance spectra) focus on simplified models based on electroneutrality assumption, equivalent circuit models, equilibrium or steady-state, thus ignoring electrochemical migration and time-dependent effects, respectively [1]. These theoretical approaches, due to their idealizations, make theorizing on ion distributions and electrical potentials in space and time domains impossible.For the above reasons, the approach of Brumleve and Buck based on Nernst-Planck and Poisson (NPP) equations is utilized here to model the transient behavior of various electrochemical processes [11]. Additionally, including several layers and reaction terms in mass balance equation allows extending the applications to such areas as: selectivity and the low detection limit with variability over time, influence of parameters, such as ion diffusivity, membrane thickness, permittivity, rate constants and primary to interfering ion concentration ratios on ion-sensor responses. Moreover solution of the NPP inverse problem allows searching for optimal sensor properties and measurement conditions. The conditions under which experimentally measured selectivity coefficients are true (unbiased) and detection limits are optimized are demonstrated, and practical conclusions relevant to clinical measurements and bioassays are derived [7].Another important field of application includes modeling of durability and diagnosis of reinforced concrete [9]. Based on extended NPP model electrochemical impedance spectra (EIS) can be obtained and analyzed to predict steel and concrete corrosion and finally utilize to prevent material failure.NPP model can be also the useful tool in description of biological systems [10]. The NPP model has the potential to reopen frontiers in the study of variety of the problems related to the electrochemistry of biological membranes. Challenges in modeling of ionic channels in biological systems are discussed.

Sorption of metal cations on suspended bentonite: effects of pH, ionic strength and complexing anions

Abstract Batch sorption experiments have been carried out to understand the interaction of different metal cations such as Am(III), Eu(III), Sr(II), and Cs(I) with bentonite clay at varying pH (1–9). The effects of other experimental parameters such as ionic strength (0.01–1 M (NaClO4)), clay to metal ion concentration ratio, and the presence of complexing anions such as oxalic acid (ox), carbonate (CO3 2−), ethylenediaminetetraacetic acid (EDTA), and humic acid (HA) on Eu(III) sorption have also been investigated. The sorption of Eu(III) has been found to be invariant with the change in ionic strength suggesting inner-sphere complexation on the bentonite surface. Near quantitative sorption of Eu(III) and Am(III) has been observed in the entire pH range and there is marginal influence of the presence of 1 · 10 –4 M of ox and CO3 2− on the sorption profile. However, the presence of 1 · 10 –4 M EDTA suppresses the sorption of Eu(III) ion onto bentonite. Desorption studies of Eu(III) loaded onto bentonite using varying concentrations of HClO4 (0.01–1.0 M) solutions reveal that higher acidity favors the process. The sorption of Eu(III) on bentonite followed the Langmuir isotherm suggesting monolayer sorption process. The data fitting to D-R isotherm suggested that the Eu(III) sorption on bentonite follows ion exchange mechanism. The sorption capacity of bentonite clay was determined to be 3.8(± 0.1) × 10−4 moles/g using Langmuir and D-R isotherms.

Electrosynthesis of Dysprosium Borides in NaCl–KCl Melt at 973 K

In this work results of joint fluorborate and dysprosium-ions electroreduction and determination of hightemperature electrochemical dysprosium borides synthesis conditions are presented. The electroreduction of dysprosium and boron ions was carried out in KCl-NaCl melts at the 973K on tungsten electrodes by the linear and cyclic voltammetry. As a result of these researches the optimal concentration ratio of dysprosium and boron ions and anion composition in melts were established for the joint Dy and B electroreduction. The analysis of voltammograms showed that the electroreduction process of investigated systems have a kinetic mode. Synthesis of ultra-disperse powders of dysprosium borides was carried out by potentiostatic electrolysis in molten equimolar KCl-NaCl with DyCl3 and KBF4. Electrolysis was carried out on tungsten and silver electrodes in the range of -2.5 to -2.8 V relatively of the quasi-stationary glass-carbon electrode. The electrosynthesis can be represented as sequence stages: an allocation of the more electropositive component (B); an allocation of the more electronegative component (Dy) on deposited boron surface; the diffusion of dysprosium and boron with formation of boride phases. The influence of the electrolyte composition, temperature, current density, voltage, electrolysis duration on synthesis products was studied. Optimal parameters for dysprosium boride DyB6 synthesis were found.

Theoretical simulation of the ion current rectification (ICR) in nano-pores based on the Poisson–Nernst–Planck (PNP) model

Ion current rectification is an important phenomenon for diode-like nano-channels, which can give the ion-selectivity of the channel. Using the PNP model for theoretical simulation can help to investigate the ICR properties, as well as to calculate the rectification ratio and profile of ion concentration along the channel. In this review, we will present the main factors that will influence the ICR effect, which are the surface charge density, the electrolyte solution concentration gradient, and the shape or geometry of the nano-pore. The applications of the PNP model used for the theoretical simulation on these factors will also be discussed.

Seawater inrush assessment based on hydrochemical analysis enhanced by hierarchy clustering in an undersea goldmine pit, China

Seawater inrush is deadly to undersea mine and it is very important to accurately assess the connectivity between seawater and the mine pit. With Xinli gold mine area as a case study, following the analysis of geological setting, a detailed hydrogeological survey and sampling were conducted and conservative ions test of mine water samples was carried out in the laboratory. Furthermore, the physical significances of ion concentration and ion ratios, such as Cl−, γSO4 2−/γCl− and γNa+/γCl−, were checked. The test data analysis, enhanced by the physical significance check and hierarchy clustering analysis, was used to assess the overlying seawater inrush into the mine pit. It was determined that the undersea rock masses in the Xinli mine area bear high-mineralization brine water. The ore-controlling fault gouge and a thin layer of clay in Quaternary block the seepage of overlying seawater into the undersea mine pit to a great extent. The mine water from surrounding rock of the northeast gopher drift is closer to seawater in hydrogeochemical features, which indicates that the connectivity between the northeast of footwall of the ore-controlling fault and seawater is relatively good and should be closely monitored in future production. The mine water from the southwest gopher drift and crosscuts is similar to the brine (salty) water in chemical features, drains the net reserves of brine (salty) water in bedrock fissures and will impose few impacts on production in the near future. This approach is feasible and cost-effective.

Potential application of oat for phytoremediation of salt ions in coastal saline-alkali soil

Improvement of saline-alkali soils by biological means is a strategic soil conservation method. To investigate the capacity of oat for phytoremediation, two factor randomized block design experiments are carried out in coastal North China. The two factors — oat variety (“Ba You-1” – BU, “Hua Zao-2” – HZ and “Bai Yan-2” – BY) and soil salinity (1.0, 2.0 and 3.0gkg−1) — are analyzed for oat biomass, straw ion accumulation and straw-to-soil ion concentration ratio. Results show that oat biomass be affected by harvest time and soil salinity. BU biomass decreases by 0.4tha−1 for harvest delay by 20 days. And BY biomass drops severely which from 3.1tha−1 in low soil salinity to 0.4tha−1 in high soil salinity. The straw ion concentration (except Ca2+) significantly drops when harvest is delayed, but it increases with soil salinity increases though K+ concentration markedly decreases. For the straw ion accumulation, the highest value for harvest time is at maturity (146.4kgha−1 for BU) and for soil salinity is at low level (100.2kgha−1 for BY) and it turns sharp decrease with the time delaying and soil salinity increasing. Ions changes in stem significantly lower than that of in leaf whatever delay harvest time or increases soil salinity. Under medium soil salt concentration, the straw-to-soil total ion concentration ratios are respectively 31.7, 32.5 and 31.3 for BU, BY and HZ. The correlation analysis reveals that oat ion accumulation is positively correlated with biomass. Besides, straw Na+ and Cl− accumulation is respectively negatively (p<0.05) correlated with K+. According to above that oat is a potential plant species in improvement of saline soil. However the low biomass and salinity tolerance limit its practical application in coastal saline-alkali soils North China.

Electrocatalytic performance of poly(o-phenylenediamine)-Pt–Ru nanocomposite for methanol oxidation

The electrocatalytic properties of poly(o-phenylenediamine) (PoPD)-Pt–Ru nanocomposite electrode for methanol oxidation have been investigated by linear sweep and cyclic voltammetry. The Pt–Ru ion concentration ratio in the electrodeposition bath is varied in the ratios of 1:0.25, 1:0.5, 1:1, 1:2, and 1:4. The morphology and particle size of the nanocomposites are obtained from the scanning electron microscopy data. The onset potential for the oxidation of methanol is found to be effectively reduced by 220 mV for the (PoPD)-Pt–Ru (1:1) nanocomposite compared to PoPD-Pt electrode. Also, the PoPD-Pt–Ru (1:1) composite shows a value of 4.2 for the ratio of forward to reverse peak current which is relatively a high value that can be observed among the conducting polymer-based catalysts used for methanol oxidation. The results are substantiated by the polarization and stability data.

Poly(acrylic acid-co-maleic acid) for the enhanced treatment of Cu (II)-loaded aqueous solution and its reuse by ultrafiltration–electrolytic process

A hybrid ultrafiltration–electrolytic process is proposed for the recovery of copper from synthetic aqueous effluents, using poly(acrylic acid-co-maleic acid) (PMA) as water-soluble polymer. The three necessary stages, namely, metal retention, polymer regeneration, and polymer reuse were studied. In a previous stage, the optimal operation parameter of pH was obtained for a copper retention yield of 99.84% with a PMA/Cu(II) ion concentration ratio of 6:1. The effect of PMA on membrane surface fouling morphology was also investigated. In the electrodeposition stage, metal recovery and polymer regeneration were studied. Scanning electron microscopy–energy dispersive spectroscopy of cathode surface was conducted to determine the effect of polymer on metal deposition morphology. Finally, a discontinuous mode of experiments was conducted to investigate the reuse of regenerated PMA for metal retention and to determine the capabilities of functional groups for complexation.

A study on electrodeposited Co–Mo alloys thin films

Cobalt–Molybdenum (Co–Mo) induced electrodeposition has been studied from a sulphate bath on Ru electrodes at pH 4. The conditions of electrodeposition of Co–Mo alloys were determined using the cyclic voltametry at different ions concentration ratios. The theoretical model of Scharifker-Hills was used to analyse the current transients for studying the first stage of nucleation of Co–Mo alloys. The electrodeposited coatings were analysed by scanning electron microscopy, X-rays diffraction and alternating gradient force magnetometer techniques. The cyclic voltametry shows that the codeposition of Co–Mo alloys was accompanied by concurrent reactions such as the formation of the molybdenum oxides and the hydrogen evolution reaction. For the electrodeposited Co–Mo, the nucleation is in good agreement with the instantaneous nucleation and three-dimensional (3D) diffusion-limited growth. Co–Mo thin films of an hcp structure have been obtained, and the electrodeposition parameters such as the applied potential have a great influence on the structure, morphology and magnetic properties.

On the Concept of Resting Potential—Pumping Ratio of the Na+/K+ Pump and Concentration Ratios of Potassium Ions Outside and Inside the Cell to Sodium Ions Inside and Outside the Cell

In animal cells, the resting potential is established by the concentration gradients of sodium and potassium ions and the different permeabilities of the cell membrane to them. The large concentration gradients of sodium and potassium ions are maintained by the Na⁺/K⁺ pump. Under physiological conditions, the pump transports three sodium ions out of and two potassium ions into the cell per ATP hydrolyzed. However, unlike other primary or secondary active transporters, the Na⁺/K⁺ pump does not work at the equilibrium state, so the pumping ratio is not a thermodynamic property of the pump. In this article, I propose a dipole-charging model of the Na⁺/K⁺ pump to prove that the three Na⁺ to two K⁺ pumping ratio of the Na⁺/K⁺ pump is determined by the ratio of the ionic mobilities of potassium to sodium ions, which is to ensure the time constant τ and the τ-dependent processes, such as the normal working state of the Na⁺/K⁺ pump and the propagation of an action potential. Further, the concentration ratios of potassium ions outside and inside the cell to sodium ions inside and outside the cell are 0.3027 and 0.9788, respectively, and the sum of the potassium and sodium equilibrium potentials is -30.3 mV. A comparative study on these constants is made for some marine, freshwater and terrestrial animals. These findings suggest that the pumping ratio of the Na⁺/K⁺ pump and the ion concentration ratios play a role in the evolution of animal cells.

Kinetics of acetaminophen degradation by Fenton oxidation in a fluidized-bed reactor

Acetaminophen (ACT), an analgesic and antipyretic substance, is one of the most commonly detected pharmaceutical compound in surface waters and wastewaters. In this study, fluidized-bed Fenton (FB-Fenton) was used to decompose ACT into its final degradation products. The 1.45-L cylindrical glass reactor had inlet, outlet and recirculating sections. SiO2 carrier particles were supported by glass beads with 2–4mm in diameter. ACT concentration was determined by high performance liquid chromatography (HPLC). During the first 40min of reaction, a fast initial ACT removal was observed and the “two-stage” ACT degradation conformed to a pseudo reaction kinetics. The effects of ferrous ion dosage and [Fe2+]/[H2O2] (FH ratio) were integrated into the derived pseudo second-order kinetic model. A reaction pathway was proposed based on the intermediates detected through SPME/GC–MS. The aromatic intermediates identified were hydroquinone, benzaldehydes and benzoic acids while the non-aromatic substances include alcohols, ketones, aldehydes and carboxylic acids. Rapid initial ACT degradation rate can be accomplished by high initial ferrous ion concentration and/or low FH ratio.

Rate redox-controlled green photosynthesis of gold nanoparticles using H3 + x PMo12 − x V x O40

Stabilized and size-controlled gold nanoparticles were synthesized using molybdophosphoric acid (H3[PMo12O40], HPMo) and its vanadium-substituted mixed addenda (H3 + x [PMo12 − x V x O40], (x = 0–3); and HPMoVx) under UV irradiation by a simple green method. In the process, HPMo and HPMoV x play the role of photocatalyst, reducing agent and efficient stabilizer. Control of gold nanoparticles size was achieved by variation of initial gold ions concentration and molar ratio of HPMo to gold ions. The synthesis rate of Au nanoparticles was found to be parallel to an increasing x value in the order of: HPMoV3 > HPMoV2 > HPMoV > HPMo, which leads to smaller and more uniform particles. Also, by substitution of vanadium instead of molybdenum in the HPMo formula, the morphology of nanoparticles was gradually changed from spherical-shaped nanoparticles in the presence of HPMo to nanorods in the case of HPMoV3.

Fabrication of Zinc Oxide Semiconductor Nanoparticles in the Apoferritin Cavity

We developed a liquid phase ZnO nanoparticles (NPs) fabrication method which employed the cage-shaped protein apoferritin as a biotemplate. The suppression of the chemical reaction outside apoferritin by stabilizing Zn2+ with ammonia allowed the selective NP synthesis inside the cavity at room temperature. The composition of synthesized NPs was confirmed to be that of ZnO, and their size was determined to be 5.1 ± 0.8 nm in diameter through energy-dispersive X-ray spectroscopy and high-resolution transmission electron microscopy. In-depth studies about the effect of anion species on the NP formation proved that the anion introduction through the channels was competitive and also that the decrease in hydroxide ion (OH–) concentration ratio in the reaction solution led to less ZnO NPs formation.

SU-E-I-78: Neuromelanin in the Subthalamic Nucleus of Patients with Parkinson's Disease: An Electron Spin Resonance Spectroscopy Study.

Parkinson disease and related syndromes are associated directly with the concentrations of neuromelanin, iron and other heavy metals, and nowadays it is discussed the possible protective role of neuromelanin by the sequester redox active iron ions, reducing the formation of free hydroxyl radicals and therefore inactivating the iron ions that induce oxidative stress. The aim of this work is to study the concentration ratios between iron ions and neuromelanin in subthalamic nucleus of patients with Parkinson's disease (PD) using Electron Spin Resonance (ESR). Necropsy samples of subthalamic nucleus from eight human brains were studied: three non-affected by any neurodegenerative disease and five with Parkinson's disease. The samples were stored in formaldehyde and washed with a solution of 0.01 molar of ethylenediaminetetraacetic acid. ESR experiments were development in a JEOL FA-200 X-Band spectrometer at different temperatures between -170° C to room temperature. The relative concentrations of each species were estimated from the double integral values of the fitted spectra. For all samples, ESR spectra showed to be composed of three different signals following the Curie's law. One signal was attributed to high-spin ferric ions (g∼ 4.3) in rhomboedric symmetry, Cu(II) ions (close to g=2.0) and neuromelanin (g∼ 2.01). The ferric ions concentration ratio between patients and controls was 3.0±0.2. The same ratio for neuromelanine was 0.24±0.06. Our preliminary results indicated a significant increment of iron concentration in PD samples which agrees with previous histochemical and biochemical reports. This finding and the clear reduction of neuromelanin concentration in PD samples suggest the possible role of neuromelanin as iron ions storage.

Recovery of Heavy Metal Using Solvent Impregnated Resin (SIR) Coupled with Donnan Dialysis

A membrane process for metal recovery from aqueous solutions was studied. Metal ions diffused from the feed compartment to the stripping compartment through an hybrid Donnan dialysis which consists to combine two ion exchange membranes with solvent impregnated resin (SIR). The aim of this work is to study the recovery of Pb(II), Ag(I) and Cu(II) from nitrate solutions by using SIR combined with classical Donnan dialysis. The resin has been prepared by impregnating the Amberlite XAD-4 using three different extractants namely: di-2-ethyl hexyl phosphine acide (D2EHPA), tris-octyl phosphine oxide (TOPO) and Diphenylthiourea (DPT). Experiments were performed as a function of nature of the extractant impregnated on the XAD-4 resin as well as the concentration in the resin phase, the stripping pH, the concentration ratio of metal ions in the feed compartment and the nature of the counter ions in strip compartment. The results show that the D2EHPA is the better extractant for the metal ions used in this work, and it’s shown a good selectivity for the separation between ions.

Struvite 결정화 반응을 이용한 고온 소화 여과액의 N, P 처리 특성

Recently, auto-thermal thermophilic aerobic digestion (ATAD) has a great attention for destruction of wasted sludge biomass in wastewater treatment plant. Reduction of sludge concentration has been successfully achieved with pilot scale ATAD and ceramic filtration process in field condition. However, high concentration of COD, total nitrogen (TN) and total phosphorus (TP) was observed in filtrate, which should be treated before recirculation of filtrate to biological wastewater treatment plant. This study was focused on removal of nitrogen and phosphorus contained in the filtrate of ATAD, using struvite crystallization method. The effect of operational and environmental parameters (such as, N, P and Mg ion concentration and molar ratio, pH, reaction time, agitation strength, seed dosage, and reaction temperature) on the treatment of TN and TP with struvite crystallization were evaluated. Magnesium (as MgCl26H2O) and phosphorus (as K2HPO4) ions were, if necessary, added to increase nitrogen removal efficiency by the crystal formation. Average concentration of NH4-N and PO4-P of the filtrate were 1716.5 mg/L and 325.5 mg/L, respectively. Relationship between removal efficiencies of nitrogen and phosphorus and molar ratios of Mg and PO4-P to NH4-N was examined. Crystal formation and nitrogen removal efficiencies were significantly increased as increasing molar ratios of magnesium and phosphorus to nitrogen. As molar ratio of Mg : PO4-P : NH4-N were maintained to 2 : 1 : 1 and 2 : 2 : 1, removal efficiencies of nitrogen and phosphorus were 71.6% and 99.9%, and 93.8% and 98.6%, respectively. However, the effect of reaction time, mixing intensity, seed dose and temperature on the struvite crystallization reaction was not significant, comparing to those of molar ratios. Settled sludge volume after struvite crystallization was observed to be reduced with increase of seed dose and to be increased at high temperature.

Fabrication of CoZn alloy nanowire arrays: Significant improvement in magnetic properties by annealing process

Highly ordered arrays of Co 1− x Zn x (0 ≤ x ≤ 0.74) nanowires (NWs) with diameters of ∼35 nm and high length-to-diameter ratios (up to 150) were fabricated by co-electrodeposition of Co and Zn into pores of anodized aluminum oxide (AAO) templates. The Co and Zn contents of the NWs were adjusted by varying the ratio of Zn and Co ion concentrations in the electrolyte. The effect of the Zn content, electrodeposition conditions (frequency and pH) and annealing on the structural and magnetic properties (e.g., coercivity (Hc) and squareness (Sq)) of NW arrays were investigated using X-ray diffraction (XRD), scanning electron microscopy, electron diffraction, and alternating gradient force magnetometer (AGFM). XRD patterns reveal that an increase in the concentration of Zn ions of the electrolyte forces the hcp crystal structure of Co NWs to change into an amorphous phase, resulting in a significant reduction in Hc. It was found that the magnetic properties of NWs can be significantly improved by appropriate annealing process. The highest values for Hc (2050 Oe) and Sq (0.98) were obtained for NWs electrodeposited using 0.95/0.05 Co:Zn concentrations at 200 Hz and annealed at 575 °C. While the pH of electrolyte is found to have no significant effect on the structural and magnetic properties of the NW arrays, the electrodeposition frequency has considerable effects on the magnetic properties of the NW arrays. The changes in magnetic property of NWs are rooted in a competition between shape anisotropy and magnetocrystalline anisotropy in NWs.