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We report on the development of a new prototype magnetic field induced flow mixer for application to flow equipment in research laboratories. This new device, designed for both agitating and mixing in tubular reactors has proven u...
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We report on the development of a new prototype magnetic field induced flow mixer for application to flow equipment in research laboratories. This new device, designed for both agitating and mixing in tubular reactors has proven useful under a number of experiments. Furthermore, the simple design allows a variety of different sized devices to be assembled straightforwardly.
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Samples of a typical tetrameric protein, the hemoglobin, at the concentration of 150 mg/ml in bidistilled water solution, were exposed to a uniform magnetic field at 200 mT at different temperatures of 15 degrees C, 40 degrees C a...
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Samples of a typical tetrameric protein, the hemoglobin, at the concentration of 150 mg/ml in bidistilled water solution, were exposed to a uniform magnetic field at 200 mT at different temperatures of 15 degrees C, 40 degrees C and 65 degrees C. Fourier Transform Infrared Spectroscopy was used to analyze the response of the secondary structure of the protein to both stress agents, heating and static magnetic field. The most relevant result which was observed was the significant increasing in intensity of the Amide I band after exposure to the uniform magnetic field at the room temperature of 15 degrees C. This result can be explained assuming that protein's alpha-helices aligned along the direction of the applied magnetic field due to their large dipole moment, inducing the alignment of the entire protein. Increasing of temperature up to 40 degrees C and 65 degrees C induced a significant reduction of the increasing in intensity of the Amide I band. This effect may be easily explained assuming that Brownian motion of the protein in water solution caused by thermal molecular agitation increased with increasing of temperature, contrasting the effect of the torque of the magnetic field applied to the protein in water solution. (C) 2018 Elsevier B.V. All rights reserved.
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The influence of the interplanetary magnetic field (IMF) B_y component on the field-aligned currents (FACs) in the plasma sheet boundary layer (PSBL) in the magnetotail during the northward IMF were investigated using the data fro...
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The influence of the interplanetary magnetic field (IMF) B_y component on the field-aligned currents (FACs) in the plasma sheet boundary layer (PSBL) in the magnetotail during the northward IMF were investigated using the data from Cluster. There are 748 FACs cases selected to do analysis. We present that the IMF B_y component plays a very important role in controlling the flow direction of the FACs in the PSBL in the magnetotail. In the northern hemisphere, the influence of the positive (negative) IMF B_y is an earthward (tailward) FACs. To the contrary, in the southern hemisphere, the effect of the positive (negative) IMF B_y is a tailward (earthward) FACs. There is a clear north-south asymmetry of the polarity of the FACs in the PSBL when IMF B_y is positive or negative, and this asymmetry of the polarity is more distinct when IMF B_y is positive. The FAC density is controlled by IMF B_y only when |IMF B_y| is large. When |IMF B_y| is more than 10 nT the absolute FAC density in the PSBL has an obvious positive correlation with the |IMF B_y|. When |IMF B_y| is less than 10 nT, there is no correlation between the absolute FAC density and |IMF B_y|. There is a clear dusk-dawn asymmetry in the current densities for the FACs in the PSBL, with the dawn currents appearing larger than the dusk currents. The FAC with the largest (smallest) density is located in the range of 0100 ≤ MLT < 0200 (2100 ≤ MLT < 2200).
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The thickness dependence of a magnetic field from which the rotational hysteresis loss has vanished was experimentally investigated for CoCrPtB perpendicular recording media. It was clarified that (1) in Co_(72)Cr_(16)Pt_8B_4 medi...
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The thickness dependence of a magnetic field from which the rotational hysteresis loss has vanished was experimentally investigated for CoCrPtB perpendicular recording media. It was clarified that (1) in Co_(72)Cr_(16)Pt_8B_4 media with film thickness d_(mag.) under 200 nm and Co_(64)Cr_(24)Pt_8B_4 media with d_(mag.) under 100 nm, a homogeneous structure was realized, except for the existence of an initial growth region with a thickness of about 2nm; (2) for both media, the perpendicular rotational hysteresis loss W_r, the maximum field of W_r, H_p, and the filed where W_r=0, H_(wr)=0, increase with increasing d_(mag.) (3) for both media, H_(Wr=0) increases with increasing d_(mag.) and saturates at a field of about magnetic anisotropy field H_k~(grain); and (4) for a medium with a thin magnetic film, at an applied field H_(Wr=0)收起
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Highly precise magnetic field calculations must be conducted for superconducting bulk magnets at least 3 mm above the surface for cryocooler-cooling applications; in practice, calculations must be conducted for those at a distance...
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Highly precise magnetic field calculations must be conducted for superconducting bulk magnets at least 3 mm above the surface for cryocooler-cooling applications; in practice, calculations must be conducted for those at a distance of 5 mm from the surface. However, the reflection of the fluxoid affects the precision of the magnetic field calculations for superconducting bulk magnets but this effect has yet to be accounted for. Here, this effect was approximated and incorporated into the magnetic field calculations for superconducting bulk magnets. The numerical results were then compared with the experimental results. The data shows that the error was less than 4% at distances above 3 mm from the bulk surface in the magnetic field calculations performed by the new method. It is expected that the calculation error can be corrected in future studies by comparing the extra-polative semi-empirical model, like that presented here, with mesoscopic calculation models. These findings will be useful in the design of devices containing highly homogeneous superconducting magnets.
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A magnetic solid phase extraction method based on agarose coated magnetic nanoparti-cles)ACMNPs(coupled to a new magnetic field agitation (MFA) device was developed and investigated for the separation, preconcentration and determi...
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A magnetic solid phase extraction method based on agarose coated magnetic nanoparti-cles)ACMNPs(coupled to a new magnetic field agitation (MFA) device was developed and investigated for the separation, preconcentration and determination of Pd(II) in aqueous solutions. For the first time, the formation of the nanoparticles and their encapsulation in agarose micro-flakes was conducted in a single step. For this purpose, preparation of the magnetic iron oxide nanoparticles was performed in an alkaline agarose solution. The sizes of Fe3O4 nanoparticles, and agarose micro-flakes were 10-14 nm and 90-130 μm, respectively. The nanomagnetic agarose particles were functionalized by iminodiacetic acid and subjected to magnetic field agitation in the MFA device. The influence of different analytical parameters such as pH, ionic strength, type and volume of desorption solvent and amount of the adsorbent on the preconcentration of Pd(II) were investigated. Eight replicated analysis at the optimized conditions, resulted in a recovery of 94.1% with an RSD of 5.2% for Pd(II). The detection limit of the method (3σ) was 47 ng L~(-1) for the analyte. The method was successfully applied to the determination of Pd(II) in natural water samples.
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The performance of synchrotron radiation facilities and free electron lasers facilities relies not only on the quality of the electron beam but also on that of the undulator. To shim field errors stemming from the undulator's manu...
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The performance of synchrotron radiation facilities and free electron lasers facilities relies not only on the quality of the electron beam but also on that of the undulator. To shim field errors stemming from the undulator's manufacturing process, precise magnetic field measurements are imperative. The traditional measurement approach involves point-by-point assessments using Hall probes. However, deploying Hall probes for magnetic measurements becomes significantly more challenging when confronted with circumstances such as small gaps, closed gaps, or mechanical constraints, as is the case with superconducting undulators. In the pulsed wire method, an extremely thin wire is employed, allowing for direct measurement of the first and second integrals of the magnetic field, even within confined spaces. This method comes with several drawbacks, including wire sagging due to its weight, dispersion effects, attenuation of transverse waves in the wire, and the potential for stray signals resulting from wire irregularities or impurities. Nevertheless, after years of refinement, this method's accuracy has markedly improved. This paper introduces the development of the pulsed wire method at the Shanghai Synchrotron Radiation Facility.
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Measuring the magnetic field of permanent magnets can be challenging, but recent research has demonstrated the potential of using deformed diamagnetic liquids to estimate the magnetic field. In this article, we explore two methods...
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Measuring the magnetic field of permanent magnets can be challenging, but recent research has demonstrated the potential of using deformed diamagnetic liquids to estimate the magnetic field. In this article, we explore two methods for measuring the magnetic field from the response of the diamagnetic liquid. The first method involves measuring the profile of the deformed liquid with a laser and then calculating the square of the magnetic field using an appropriate equation. The second method involves measuring the maximum slope of the liquid and numerically calculating the magnetic field distribution using the model of an ideal solenoid. We present the experimental results using these methods and compare them with other established methods for measuring magnetic fields. The results show that the proposed methods are effective and have potential for use in a variety of applications. The proposed methods can help address the challenge of measuring magnetic fields in situations where other methods are not suitable or practical.
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The technology of capsule endoscopy becomes very popular nowadays for its painlessness, effectiveness, usability and uniqueness. In this paper, a magnetically based controllable wireless endoscope capsule is reviewed. A capsule co...
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The technology of capsule endoscopy becomes very popular nowadays for its painlessness, effectiveness, usability and uniqueness. In this paper, a magnetically based controllable wireless endoscope capsule is reviewed. A capsule contains magnets in theshape of doughnuts, which enables to control it by means of magnetic setup and control panel. A setup contains superconducting magnet, which provides the high intensity of magnetic field, and this enables to examine patient of any constitution. The external control over the location of a capsule is conducted by the effect of low frequency or even steady magnetic field, which does not have side effect and is able to penetrate freely with biological tissue without significant weakening.
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