Journal articles: 'Magnets – Viscosity'

1

Martinez, J. C., and F. P. Missell. "MAGNETIC VISCOSITY IN NdFeB MAGNETS." Le Journal de Physique Colloques 49, no. C8 (December 1988): C8–649—C8–650. http://dx.doi.org/10.1051/jphyscol:19888294.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

Liu, Jinfang, Helie Luo, and Shuming Pan. "Magnetic viscosity studies of Nd16Fe77B7permanent magnets." Journal of Applied Physics 69, no. 8 (April 15, 1991): 5557–58. http://dx.doi.org/10.1063/1.347948.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Martinez, J. C., and F. P. Missell. "Magnetic viscosity and texture in NdFeB magnets." Journal of Applied Physics 64, no. 10 (November 15, 1988): 5726–28. http://dx.doi.org/10.1063/1.342239.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Skomski, R. "Magnetic Viscosity of Interacting Fine Particle Magnets." physica status solidi (b) 165, no. 1 (May 1, 1991): K27—K32. http://dx.doi.org/10.1002/pssb.2221650134.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

LoBue, M., V. Basso, G. Beatrice, C. Bertotti, G. Durin, and C. P. Sasso. "Barkhausen jumps and magnetic viscosity in NdFeB magnets." Journal of Magnetism and Magnetic Materials 290-291 (April 2005): 1184–87. http://dx.doi.org/10.1016/j.jmmm.2004.11.380.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Givord, D., P. Tenaud, T. Viadieu, and G. Hadjipanayis. "Magnetic viscosity in different Nd‐Fe‐B magnets." Journal of Applied Physics 61, no. 8 (April 15, 1987): 3454–56. http://dx.doi.org/10.1063/1.338751.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Thompson, P. J., and R. Street. "Viscosity, reptation and tilting effects in permanent magnets." Journal of Physics D: Applied Physics 30, no. 9 (May 7, 1997): 1273–84. http://dx.doi.org/10.1088/0022-3727/30/9/002.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Givord, D., A. Lienard, P. Tenaud, and T. Viadieu. "Magnetic viscosity in Nd-Fe-B sintered magnets." Journal of Magnetism and Magnetic Materials 67, no. 3 (July 1987): L281—L285. http://dx.doi.org/10.1016/0304-8853(87)90185-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Villas-Boas, V., J. M. Gonzalez, F. Cebollada, M. F. Rossignol, D. W. Taylor, and D. Givord. "Coercivity and magnetic viscosity of NdDyFeB mechanically alloyed magnets." IEEE Transactions on Magnetics 31, no. 6 (1995): 3647–49. http://dx.doi.org/10.1109/20.489597.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Cornejo, D. R., V. Villas-Boas, and F. P. Missell. "Reversible processes and magnetic viscosity of nanocrystalline permanent magnets." Journal of Applied Physics 83, no. 11 (June 1998): 6637–39. http://dx.doi.org/10.1063/1.367784.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

HART, J. E. "Ferromagnetic rotating Couette flow: the role of magnetic viscosity." Journal of Fluid Mechanics 453 (February 25, 2002): 21–38. http://dx.doi.org/10.1017/s0022112001006590.

Full text

Abstract:

A theory is constructed for rotating plane Couette flow of ferrofluid that is subject to the field generated by a periodic array of magnets. The system that is analysed contains a substantial lateral magnetic buoyancy, or magnetic gravity, allowing the configuration to be used in experimental studies of stratified shear flows in a connected geometry.However, the spatial variation of the magnetic vector field of the magnet stack leads to magnetically generated wavy flows via the action of flow vorticity on the particle orientation in the suspension. The basic rotating Couette flow instabilities may also be affected by the same mechanism, which is sometimes referred to as rotational or ‘magnetic viscosity’. Theoretical calculations show that the directly excited wavy flows are generally small, for anticipated experimental conditions, except when they resonate with the natural linear instabilities of the Couette flow. A weakly nonlinear analysis is carried out in order to predict the behaviour in these cases. Magnetic effects stabilize the fundamental roll instability of rotating Couette flow by about 10% for a typical laboratory realization.

APA, Harvard, Vancouver, ISO, and other styles

12

Espina-Hernández, J. H., Roland Grössinger, Reiko Sato Turtelli, and J. M. Hallen. "A New Measuring System for Determining the Magnetic Viscosity in Permanent Magnets." Advanced Materials Research 68 (April 2009): 12–20. http://dx.doi.org/10.4028/www.scientific.net/amr.68.12.

Full text

Abstract:

A new system for measuring magnetic viscosity in bulk hard magnetic materials base on a pulsed field method is presented. After the magnetizing field pulse, the stray field of the sample, which is proportional to the magnetic moment, is measured with a compensated set of two Hall probes. The set of Hall probes is driven with an AC voltage source and the Hall voltage is detected using a lock-in amplifier. By this method the system is able to measure the time dependence of the magnetization (viscosity). The magnetic viscosity coefficient (S) is obtained through a linear fitting of the magnetization decay versus ln t. Two typical Nd-Fe-B samples were measured and good agreement with the results from the traditional viscosity experiment was obtained.

APA, Harvard, Vancouver, ISO, and other styles

13

Thompson, P. J., and R. Street. "Magnetic viscosity and barkhausen noise in NdFeB-type permanent magnets." Journal of Magnetism and Magnetic Materials 171, no. 1-2 (July 1997): 153–62. http://dx.doi.org/10.1016/s0304-8853(97)00059-0.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Tejada, J., X. X. Zhang, and Ll Balcells. "Nonthermal viscosity in magnets: Quantum tunneling of the magnetization (invited)." Journal of Applied Physics 73, no. 10 (May 15, 1993): 6709–14. http://dx.doi.org/10.1063/1.352509.

Full text

APA, Harvard, Vancouver, ISO, and other styles

15

Nishimura, K., and M. Inoue. "Repulsive magnets type viscosity sensor using a source of vibration." Journal of Magnetism and Magnetic Materials 310, no. 2 (March 2007): e1002-e1003. http://dx.doi.org/10.1016/j.jmmm.2006.10.1052.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Martinez, J. C. G., F. P. Missell, and F. J. G. Landgraf. "Magnetic viscosity and texture in sintered NdFeB and NdDyFeB magnets." Journal of Magnetism and Magnetic Materials 73, no. 3 (July 1988): 267–72. http://dx.doi.org/10.1016/0304-8853(88)90092-3.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Xiao, Jun, and Joshua U. Otaigbe. "Polymer-bonded magnets: Part I. Analytic thermogravimetry to determine the effect of surface modification on dispersion of Nd–Fe–B fillers." Journal of Materials Research 14, no. 7 (July 1999): 2893–96. http://dx.doi.org/10.1557/jmr.1999.0386.

Full text

Abstract:

The degree of mixing is a critical factor in controlling the magnetic properties and mechanical properties of polymer-bonded magnets. Pretreatment of the NdFeB fillers with a silane coupling agent improved the degree of mixing of the fillers in the polymer matrix. The observed improvement in the degree of mixing of the silanetreated fillers was ascribed to good wetting as evidenced by viscosity reduction of the coupled polymer-bonded magnets. However, traditional materials characterization methods could not be used to quantitatively determine the degree of mixing of the polymer-bonded magnets. This paper describes use of thermogravimetric analysis to quantify the degree of mixing of polymer-bonded magnets. The intensity of segregation of the fillers was calculated from the measured weight change of the magnetic filler in the samples. The results of this work showed that the thermogravimetric analysis method was useful in determining the degree of mixing of NdFeB fillers in polymer-bonded magnets.

APA, Harvard, Vancouver, ISO, and other styles

18

Nishio, H., and H. Yamamoto. "Magnetic Viscosity of Sr-Na-Zn W-Type Hexagonal Ferrite Magnets." Le Journal de Physique IV 07, no. C1 (March 1997): C1–317—C1–318. http://dx.doi.org/10.1051/jp4:19971125.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Jahn, L., R. Schumann, and W. Rodewald. "Magnetic viscosity of modified neodymium iron boron magnets with high coercivities." Journal of Magnetism and Magnetic Materials 153, no. 3 (February 1996): 302–10. http://dx.doi.org/10.1016/0304-8853(95)00550-1.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

SHARIFULLIN, I. A., A. L. NOSKO, E. V. SAFRONOV, and D. V. KIRILLOV. "EXPERIMENTAL STUDY OF EDDY CURRENT BRAKING APPLICABLE TO GRAVITY ROLLER CONVEYOR." Fundamental and Applied Problems of Engineering and Technology 4, no. 1 (2020): 106–16. http://dx.doi.org/10.33979/2073-7408-2020-342-4-1-106-116.

Full text

Abstract:

One of the main elements of safe operation of gravity conveyors used in gravity racks for pallets is the brake roller. The most promising design is a brake roller of magnetic (eddy current) type. A mathematical model of the process of moving pallets on a magnetic brake roller is developed. The equation of the speed of movement of the pallets on the brake magnetic roller obtained. The main parameter that determines the braking functions of the brake magnetic roller, and therefore the speed of movement of the pallet on the gravity roller conveyor is the coefficient of roller, experimental studies have been carried out to determine the magnetic viscosity coefficient. It was found that the coefficient of magnetic viscosity decreases with increasing air gap between the conductive body and the permanent magnets, and this dependence has a power-law character; decreases by 10... 25% with increasing speed of the conductive body; independent of changes in the distance between the centers of the conductive body and the permanent magnet; decreases when an edge effect appears in accordance with the air gap.

APA, Harvard, Vancouver, ISO, and other styles

21

Tejada, J., X. X. Zhang, Ll Balcells, O. Iglesias, and B. Barbara. "Non-Thermal Viscosity in the Magnetic Relaxation of 2 d Random Magnets." Europhysics Letters (EPL) 22, no. 3 (April 20, 1993): 211–16. http://dx.doi.org/10.1209/0295-5075/22/3/009.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Дмитриев, А. И. "Временная стабильность намагниченности наночастиц varepsilon-In-=SUB=-0.24-=/SUB=- Fe-=SUB=-1.76-=/SUB=-O-=SUB=-3-=/SUB=-." Письма в журнал технической физики 44, no. 4 (2018): 17. http://dx.doi.org/10.21883/pjtf.2018.04.45634.16923.

Full text

Abstract:

AbstractThe kinetics of spontaneous demagnetization in nanoparticles of the exotic epsilon-phase of indium-doped iron(III) oxide (ε-In_0.24Fe_1.76O_3) has been studied using the method of accelerated testing of magnets for temporal stability in a magnetization-reversal field. Time dependences of the magnetization of nanoparticles measured in a wide range of magnetic fields exhibited rectification in semilogarithmic coordinates. The dependence of the magnetic viscosity on the magnetic field has been measured and used for determining the fluctuation field and activation volume. A relationship between the magnetic viscosity and magnetic noise caused by random thermoinduced magnetization reversal in separate nanoparticles is established.

APA, Harvard, Vancouver, ISO, and other styles

23

Villas-Boas, V., J. M. González, F. Cebollada, M. F. Rossignol, D. W. Taylor, and D. Givord. "Magnetic viscosity and coercivity analysis in mechanically alloyed and melt-spun NdDyFeB magnets." Journal of Magnetism and Magnetic Materials 185, no. 2 (June 1998): 180–86. http://dx.doi.org/10.1016/s0304-8853(97)01159-1.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Volegova, E. A., S. V. Andreev, N. V. Selezneva, A. N. Urzhumtsev, and A. S. Volegov. "Effect of intergrain exchange interaction on magnetic viscosity of nanocrystalline isotropic NdFeB magnets." Journal of Physics: Conference Series 1389 (November 2019): 012121. http://dx.doi.org/10.1088/1742-6596/1389/1/012121.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Rudl, Johannes, Christian Hanzelmann, Steffen Feja, Anja Meyer, Annegret Potthoff, and Matthias H. Buschmann. "Laminar Pipe Flow with Mixed Convection under the Influence of Magnetic Field." Nanomaterials 11, no. 3 (March 23, 2021): 824. http://dx.doi.org/10.3390/nano11030824.

Full text

Abstract:

Magnetic influence on ferronanofluid flow is gaining increasing interest from not only the scientific community but also industry. The aim of this study is the examination of the potentials of magnetic forces to control heat transfer. Experiments are conducted to investigate the interaction between four different configurations of permanent magnets and laminar pipe flow with mixed convection. For that purpose a pipe flow test rig is operated with a water-magnetite ferronanofluid. The Reynolds number is varied over one order of magnitude (120–1200). To characterise this suspension, density, solid content, viscosity, thermal conductivity, and specific heat capacity are measured. It is found that, depending on the positioning of the magnet(s) and the Reynolds number, heat transfer is either increased or decreased. The experiments indicate that this is a local effect. After relaxation lengths ranging between 2 and 3.5 lengths of a magnet, all changes disappeared. The conclusion from these findings is that magnetic forces are rather a tool to control heat transfer locally than to enhance the overall heat transfer of heat exchangers or the like. Magnetically caused disturbances decay due to viscous dissipation and the flow approaches the basic state again.

APA, Harvard, Vancouver, ISO, and other styles

26

Munakata, M., K. Maki, and H. Kronmüller. "Magnetizing field dependence of the viscosity parameter SV of Nd-Fe-B sintered magnets." Journal of the Magnetics Society of Japan 15, no. 2 (1991): 237–40. http://dx.doi.org/10.3379/jmsjmag.15.237.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Nishio, H., S. Hashimoto, K. Yajima, and A. Fukuno. "Effects of Sn Addition on the Magnetic Viscosity of Nd-Fe-B Sintered Magnets." Journal of the Magnetics Society of Japan 20, no. 2 (1996): 225–28. http://dx.doi.org/10.3379/jmsjmag.20.225.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Thompson, P. J., and R. Street. "A technique for simulating the effect of long-term magnetic viscosity in permanent magnets." Journal of Magnetism and Magnetic Materials 171, no. 1-2 (July 1997): 163–69. http://dx.doi.org/10.1016/s0304-8853(97)00055-3.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Garraud, Alexandra, Camilo Velez, Yash Shah, Nicolas Garraud, Bettina Kozissnik, Elena G. Yarmola, Kyle D. Allen, Jon Dobson, and David P. Arnold. "Investigation of the Capture of Magnetic Particles From High-Viscosity Fluids Using Permanent Magnets." IEEE Transactions on Biomedical Engineering 63, no. 2 (February 2016): 372–78. http://dx.doi.org/10.1109/tbme.2015.2458783.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Eckert, D., K. H. Muller, P. A. P. Wendhausen, M. Wolf, D. Givord, M. F. Rossignol, and V. Villas-Boas. "Magnetic viscosity of Zn-bonded Sm/sub 2/Fe/sub 17/N/sub x/ magnets." IEEE Transactions on Magnetics 30, no. 2 (March 1994): 574–76. http://dx.doi.org/10.1109/20.312339.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Kameoka, Takayuki, Akifumi Takahashi, Vibol Yem, Hiroyuki Kajimoto, Kohei Matsumori, Naoki Saito, and Naomi Arakawa. "Assessment of Stickiness with Pressure Distribution Sensor Using Offset Magnetic Force." Micromachines 10, no. 10 (September 27, 2019): 652. http://dx.doi.org/10.3390/mi10100652.

Full text

Abstract:

The quantification of stickiness experienced upon touching a sticky or adhesive substance has attracted intense research attention, particularly for application to haptics, virtual reality, and human–computer interactions. Here, we develop and evaluate a device that quantifies the feeling of stickiness experienced upon touching an adhesive substance. Keeping in mind that a typical pressure distribution sensor can only measure a pressing force, but not a tensile force, in our setup, we apply an offset pressure to a pressure distribution sensor and measure the tensile force generated by an adhesive substance as the difference from the offset pressure. We propose a method of using a magnetic force to generate the offset pressure and develop a measuring device using a magnet that attracts magnetic pin arrays and pin magnets; the feasibility of the method is verified with a first prototype. We develop a second prototype that overcomes the noise problems of the first, arising from the misalignment of the pins owing to the bending of the magnetic force lines at the sensor edges. We also obtain measurement results for actual samples and standard viscosity liquids. Our findings indicate the feasibility of our setup as a suitable device for measuring stickiness.

APA, Harvard, Vancouver, ISO, and other styles

32

Yamamoto, Hiroshi, Takashi Kumanbara, Hiroaki Nishio, and Shunji Suzuki. "Magnetic properties of SmNdFeCoN compounds and magnetic viscosity of their bonded magnets." Journal of Alloys and Compounds 222, no. 1-2 (May 1995): 67–72. http://dx.doi.org/10.1016/0925-8388(94)04919-x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

de Julián, C., and J. M. González. "Magnetic viscosity in melt spun magnets prepared by crystallization of amorphous precursors using different heating rates." Journal of Magnetism and Magnetic Materials 140-144 (February 1995): 1055–56. http://dx.doi.org/10.1016/0304-8853(94)01255-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Gopinadhan, Manesh, Youngwoo Choo, Kohsuke Kawabata, Gilad Kaufman, Xunda Feng, Xiaojun Di, Yekaterina Rokhlenko, et al. "Controlling orientational order in block copolymers using low-intensity magnetic fields." Proceedings of the National Academy of Sciences 114, no. 45 (October 23, 2017): E9437—E9444. http://dx.doi.org/10.1073/pnas.1712631114.

Full text

Abstract:

The interaction of fields with condensed matter during phase transitions produces a rich variety of physical phenomena. Self-assembly of liquid crystalline block copolymers (LC BCPs) in the presence of a magnetic field, for example, can result in highly oriented microstructures due to the LC BCP’s anisotropic magnetic susceptibility. We show that such oriented mesophases can be produced using low-intensity fields (<0.5 T) that are accessible using permanent magnets, in contrast to the high fields (>4 T) and superconducting magnets required to date. Low-intensity field alignment is enabled by the addition of labile mesogens that coassemble with the system’s nematic and smectic A mesophases. The alignment saturation field strength and alignment kinetics have pronounced dependences on the free mesogen concentration. Highly aligned states with orientation distribution coefficients close to unity were obtained at fields as small as 0.2 T. This remarkable field response originates in an enhancement of alignment kinetics due to a reduction in viscosity, and increased magnetostatic energy due to increases in grain size, in the presence of labile mesogens. These developments provide routes for controlling structural order in BCPs, including the possibility of producing nontrivial textures and patterns of alignment by locally screening fields using magnetic nanoparticles.

APA, Harvard, Vancouver, ISO, and other styles

35

Matsumoto, Michiaki, Takuya Yamaguchi, and Yoshiro Tahara. "Extraction of Rare Earth Metal Ions with an Undiluted Hydrophobic Pseudoprotic Ionic Liquid." Metals 10, no. 4 (April 11, 2020): 502. http://dx.doi.org/10.3390/met10040502.

Full text

Abstract:

Recovering and concentrating rare earth metals (Nd and Dy) from waste permanent magnets rather than discarding them into the environment without pretreatment is critical for metal recycling and environmental responsibility. In this work, we used an undiluted hydrophobic pseudoprotic ionic liquid composed of trioctylamine and decanoic acid as an extractant to separate rare earth metals from aqueous media with a solvent extraction technique. This ionic liquid proved to be excellent with low viscosity and extractability reaching 100% for Nd and Dy in the presence of salts like sodium chloride and sodium nitrate. In acidic media, extractability decreased with increasing acid concentrations. Under all our experimental conditions, the rare earth metals (Nd and Dy) were found to be preferentially extracted compared to nickel with the distribution ratios of Dy higher than those of Nd.

APA, Harvard, Vancouver, ISO, and other styles

36

Givord, D., C. Hieden, A. Hoehler, P. Tenaud, T. Viadieu, and K. Zeibig. "Dependence of the coercive field and magnetic viscosity coefficient in Nd-Fe-B magnets on the magnetic history of the sample." IEEE Transactions on Magnetics 24, no. 2 (March 1988): 1918–20. http://dx.doi.org/10.1109/20.11645.

Full text

APA, Harvard, Vancouver, ISO, and other styles

37

Melatos, A. "Bumpy Spin-Down of Anomalous X-Ray Pulsars: The Link with Magnetars." International Astronomical Union Colloquium 177 (2000): 691–94. http://dx.doi.org/10.1017/s0252921100060991.

Full text

Abstract:

AbstractIt is argued that bumps in the timing histories Ω(t) of the anomalous X-ray pulsars (AXPs) IE 1048.1-5937 and IE 2259+586 are the signature of a magnetar undergoing radiative precession, wherein the hydromagnetic deformation of the neutron star couples to an oscillating component of the vacuum-dipole radiation torque to produce an anharmonic wobble with periodτpr∼ 10 yr. An analysis of Euler’s equations of motion for a biaxial magnet reproduces the amplitude and recurrence time of the bumps for IE 1048.1-5937 and IE 2259+586, predicts Ω(t) for the next 20 years for both objects, and predicts a testable statistical relation betweendΩ/dtandτprfor the AXP population overall. Radiative precession of soft gamma-ray repeaters is also discussed, together with implications for the internal (e.g. viscosity) and magnetospheric (e.g.e+e−pair currents) properties of magnetars.

APA, Harvard, Vancouver, ISO, and other styles

38

Sharifullin, I. A., A. L. Nosko, and E. V. Safronov. "Сomparative analysis of calculated and experimental studies of pallet movement speed on magnetic type brake roller." Russian Automobile and Highway Industry Journal 18, no. 2 (May 20, 2021): 148–59. http://dx.doi.org/10.26518/2071-7296-2021-18-2-148-159.

Full text

Abstract:

Introduction. Increasing the efficiency of using a warehouse with a constant volume is an urgent task, the solution of which is possible through block or deep-lane storage systems. One such solution is the pallet flow rack, which saves up to 25% of the distance travelled by a forklift compared to the single-deep racks. The main element of the safe operation of the gravity roller conveyors used in a pallet flow rack is a brake roller. The most promising design is a magnetic (eddy current) type brake roller.The purpose of the work is to carry out a comparative analysis of the results of the calculated and experimental studies to determine the speed of movement of a pallet along a magnetic brake roller.Materials and methods. The research area is the magnetic brake roller. Its construction and description of work presented. The results of calculated and experimental study of the coefficient of magnetic viscosity presented.Results. The calculated and experimental dependences of the pallet movement speed along the magnetic brake roller were obtained. It was found that with an increase in the speed of movement of the pallet along the magnetic brake roller, the error of the mathematical model increases, and, first of all, after crossing with the straight line of a drag peak speed.Conclusions. A comparative analysis of the results of the calculated and experimental studies to determine the speed of movement of the pallet along the magnetic brake roller carried out. It was found that the developed design of a magnetic brake roller in the operating range of the pallet masses from 100 to 600 kg with up to 16 magnets located on one side of the disc, and from 100 to 1150 kg with up to 8 pairs of the magnets located on both sides of the disc, provides a speed control within the limits not exceeding the permissible speeds of the pallet movement on the gravitational roller conveyor. The verification of the mathematical model showed that the average value of the error of the mathematical model in the entire range of the pallet masses at speeds not exceeding the permissible speeds of pallet movement on a gravitational roller conveyor and below the drag peak speed is no more than 8.2%.

APA, Harvard, Vancouver, ISO, and other styles

39

Kovalevskyy, S., and O. Kovalevska. "MAGNETIC RESONANCE PROCESSING OF MATERIALS." Odes’kyi Politechnichnyi Universytet Pratsi 3, no. 62 (December 2020): 29–38. http://dx.doi.org/10.15276/opu.3.62.2020.04.

Full text

Abstract:

Acoustic devices for determining the elasticity modulus based on the measurement of the samples frequency resonant oscillation due to the sample exposure to acoustic waves with consistently changed frequencies. Objective: Development of an algorithm for increasing the hardness of materials due to magnetic resonance imaging. Materials and methods: The paper shows the possibility of using as a uniform flux to influence the volume of thematerial of the magnetic field formed by powerful permanent magnets. The process of influencing the volume of material of the experimental samples was that the effect of a uniform magnetic flux permeating the sample is initiated in a result of resonant oscillations of the sample caused by broadband exposure of equal amplitude using a “white noise” generator and a piezoelectric emitter. Results: Treatment of samples of materials placed in a uniform magnetic field, resonant polyfrequency vibrations with nanoscale amplitude in the range of 20...80 nm, allows you to change the viscosity of the material, the modulus of elasticity of the material and the hardness of material samples to improve the performance of these materials . Conclusions: Nanoscale amplitudes of natural oscillations of objects of complex shape in energy fields, which include uniform magnetic fields, can correct the physical and mechanical properties of materials of such objects in order to achieve their identity or add strictly defined properties.

APA, Harvard, Vancouver, ISO, and other styles

40

Thirupathi, Gadipelly, and Rajender Singh. "Magneto-viscosity of MnZn-ferrite ferrofluid." Physica B: Condensed Matter 448 (September 2014): 346–48. http://dx.doi.org/10.1016/j.physb.2014.03.042.

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Wierzcholski, Krzysztof, and Andrzej Miszczak. "Electro-magneto-hydrodynamic lubrication." Open Physics 16, no. 1 (May 30, 2018): 285–91. http://dx.doi.org/10.1515/phys-2018-0040.

Full text

Abstract:

Abstract The topic of the presented paper aims to demonstrate a new principle of hydrodynamic lubrication in mechanical, thermal and electro-magnetic fields. Up till now, when dealing with the hydrodynamic theory lubrication, many authors of scientific papers have assumed the constant oil dynamic viscosity value without variations caused by temperature crosswise the film thickness. Simultaneously, due to the numerous AFM measurements, it appears that oil temperature gradients and oil viscosity changes in the bearing gap height directions cannot be omitted. Therefore, in this paper, the problem of the viscosity changes across the lubricant thin layer was resolved as the main novelty in principles of mechanical thermal lubrication. The method of solving the mentioned problem was manifested by a general model of semi-analytical solutions of isothermal electro-magneto-elastohydro-dynamic and non-Newtonian, lubrication problem formulated for two deformable rotational surfaces in curvilinear, co-ordinates.

APA, Harvard, Vancouver, ISO, and other styles

42

Yun, Dong Won, Kyung Jinho, and Soo Hyun Kim. "Study on the Water Proof Seal for Underwater Robot Using MR Fluid." Advanced Materials Research 378-379 (October 2011): 759–62. http://dx.doi.org/10.4028/www.scientific.net/amr.378-379.759.

Full text

Abstract:

Water proofing is an obvious problem in developing successful underwater robots. In previous research, most underwater robots have used a mechanical seal for water proofing. However, this kind of seal has not proved reliable because of friction and wear between the stationary parts and moving parts. This paper presents a method to seal the moving parts in underwater robots, especially robot fish. The proposed seal for under water robots is developed using Magneto Rheology (MR) fluid. MR fluid is a kind of smart material, of which the viscosity varies with the external magnetic field. This fluid is composed of silicon oil and small magnetic particles, which are micrometer sized, and when an external magnetic field is applied to the fluid, the small particles align with the magnetic flux line. The arrays of magnetic particles in the fluid inhibit the fluid flow, which changes the viscosity of fluid. Taking advantage of this phenomenon, we devised a seal with a permanent magnet and MR fluid. Our analysis demonstrates the performance of the developed seal. The magnetic equivalent circuit method and FEM (Finite Element Method) are used to calculate the magnetic field and the analysis results show that the developed seal can sustain 10 atm pressure.

APA, Harvard, Vancouver, ISO, and other styles

43

Kawasaki, Jumpei, Yuki Nakamura, and Yasukazu Sato. "Viscosity Control of Magnetorheological Fluid by Power Saving Magnetizing Mechanism Using Movement of Permanent Magnet." Journal of Robotics and Mechatronics 32, no. 5 (October 20, 2020): 977–83. http://dx.doi.org/10.20965/jrm.2020.p0977.

Full text

Abstract:

Generally, the magnetic field applied to a magnetorheological fluid (MRF) is generated by electromagnets. Electromagnets consume electric power during MRF magnetization, which is an issue. In this study, we examine two kinds of magnetizing mechanism using a permanent magnet, instead of electromagnets, to save electric power and generate a magnetic field on the MRF. One mechanism linearly moves the permanent magnet into the magnetic circuit composed of yokes. The magnetic field intensity on the MRF is then controlled by changing the overlap between the magnet and the yokes. The other mechanism rotates a permanent magnet in the magnetic circuit. The magnetic field intensity on the MRF is then controlled by changing the relative angular position between the magnet and the yokes. These two mechanisms normally generate force or torque on the magnet toward a magnetically stable position concerning the magnet, and the force or torque causes power consumption to hold and move the magnet. We design herein special magnetic circuits and a cancelation mechanism for the force or torque that drastically reduce the power consumption during the MRF magnetization compared with an electromagnet-type magnetizing device.

APA, Harvard, Vancouver, ISO, and other styles

44

Kaptsov, I., O. Nalivaiko, O. Romashko, and R. Tkachenko. "INVESTIGATION OF THE EFFECT OF THE PERMANENT MAGNETIC FIELD OF THE MAGNETIC ANTI-PARAFFIN DEVICE ON THE STRUCTURE ASPHALT-RESIN-PARAFFIN SEDIMENT." Municipal economy of cities 4, no. 157 (September 25, 2020): 146–51. http://dx.doi.org/10.33042/2522-1809-2020-4-157-146-151.

Full text

Abstract:

The limited world oil reserves force to actively develop and use fields with relatively low debit wells, as well as fields with difficult oil production conditions, with high-viscosity oil and with a significant content of foreign inclusions. One of the most unpleasant and serious complications in oil equipment is asphalt-resin-paraffin deposits. Therefore, one of the most important tasks is to study the mechanism and conditions of formation of asphalt-resin-paraffin deposits, as well as the development of effective methods to combat them. Analysis of wells in which asphalt-resin-paraffin deposits are observed, shows that the presence of paraffin, regardless of its amount in oil, poses many technological and technical tasks related to the elimination of complications associated with asphalt-resin-paraffin deposits. The presence of asphalt-resin-paraffin deposits leads to a decrease in the flow rate of wells due to clogging of pores and deterioration of filtration of oil-saturated formations. During downhole oil production, asphalt-resin-paraffins accumulate in the form of deposits on the walls of pump-compressor pipes (tubing) and oilfield equipment, thereby reducing the cross section of pipelines and lead to a decrease in the flow rate of wells. In a given hour, there are close to twenty new ways of fighting with embedded paraffin. Leather with methods of combating paraffin waxing in the process of choosing effective methods for preserving and visualizing paraffin waxes without preserving the trivial mid-repair period of robotics in the drill holes, for improving the efficiency of mathematics. The use of magnetic oil treatment devices is effective in preventing these problems. The high practical efficiency of such devices is evidenced by the increasing attention paid to the development of these devices and their patenting by various foreign firms. One such device, called a magnetic anti-paraffin device, will be discussed in detail in this paper. The device was tested at the Boryslav field from 2002 to 2007, where it gave good results in contrast to other methods. MAP has significantly reduced the percentage of asphalt-resin-paraffin deposits formation in the production area and transferred the process of their utilization to the refinery №10 in Boryslav, which in turn allows to preserve valuable components of asphalt-resin-paraffin deposits for their further use and improve the environmental condition of oil fields. The use of magnetic antiparaffin device can be effective both in the gushing of the well and in the operation of its deep-rod centrifugal and diaphragm pumps, as well as on oil pipelines. The maintenance period due to the use of magnetic antiparaffin device, in particular at OJSC Ukrnafta, increased 1.5-2.6 times. The advanced MAP device differs from other magnetic devices for liquid processing in that no power supply to the device is required for work as it works on permanent magnets. Keywords: pipeline transportation of petroleum products, trunk oil pipelines, high viscosity oil, paraffin deposition, permanent magnetic field.

APA, Harvard, Vancouver, ISO, and other styles

45

Jain, M. K., S. Schmidt, C. Mungle, K. Loiselle, and C. A. Grimes. "Measurement of temperature and liquid viscosity using wireless magneto-acoustic/magneto-optical sensors." IEEE Transactions on Magnetics 37, no. 4 (July 2001): 2767–69. http://dx.doi.org/10.1109/20.951301.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Johannsen, Benita, Lara Müller, Desirée Baumgartner, Lena Karkossa, Susanna Früh, Nagihan Bostanci, Michal Karpíšek, Roland Zengerle, Nils Paust, and Konstantinos Mitsakakis. "Automated Pre-Analytic Processing of Whole Saliva Using Magnet-Beating for Point-of-Care Protein Biomarker Analysis." Micromachines 10, no. 12 (November 30, 2019): 833. http://dx.doi.org/10.3390/mi10120833.

Full text

Abstract:

Saliva offers many advantages for point-of-care (PoC) diagnostic applications due to non-invasive, easy, and cost-effective methods of collection. However, the complex matrix with its non-Newtonian behavior and high viscosity poses handling challenges. Several tedious and long pre-analytic steps, incompatible with PoC use, are required to liquefy and homogenize saliva samples before protein analysis can be performed. We apply magnet-beating to reduce hands-on time and to simplify sample preparation. A magnet in a chamber containing the whole saliva is actuated inside a centrifugal microfluidic cartridge by the interplay of centrifugal and magnetic forces. Rigorous mixing, which homogenizes the saliva sample, is then initiated. Consequently, fewer manual steps are required to introduce the whole saliva into the cartridge. After 4 min of magnet-beating, the processed sample can be used for protein analysis. The viscosity of whole saliva has been reduced from 10.4 to 2.3 mPa s. Immunoassay results after magnet-beating for three salivary periodontal markers (MMP-8, MMP-9, TIMP-1) showed a linear correlation with a slope of 0.99 when compared to results of reference method treated samples. Conclusively, magnet-beating has been shown to be a suitable method for the pre-analytic processing of whole saliva for fully automated PoC protein analysis.

APA, Harvard, Vancouver, ISO, and other styles

47

Li, Fu, Li Ping Lin, Wei Hu, and Guang Lei Meng. "Control Technology of Magneto-Rheological Damper Based on Impact Load." Applied Mechanics and Materials 204-208 (October 2012): 4664–67. http://dx.doi.org/10.4028/www.scientific.net/amm.204-208.4664.

Full text

Abstract:

Magneto-rheological damper is an adjustable damping smart drive. Its advantage lies that the magneto-rheological fluid can rapidly and reversibly change Newtonian fluid with good liquidity into plastic solid with high viscosity and low liquidity in the millisecond time. And then it can be easily combined with control. MR damper has obtained a certain application in vibration control of automotive, machinery, construction and other areas. In this paper, the writer focus on describing control strategy present situation and the advantages and disadvantages of various control strategies of magneto-rheological damper based on impact load. And he makes a more detailed analysis of difficulties and future trends of magneto-rheological damper based on impact load.

APA, Harvard, Vancouver, ISO, and other styles

48

SHIBAYAMA, A., T. OTOMO, Y. AKAGAMI, K. SHIMADA, and T. FUJITA. "PREPARATION AND ABRASION PROPERTIES OF MAGNETO-RHEOLOGICAL FLUID OF DISPERSED SILICA-COATED IRON." International Journal of Modern Physics B 19, no. 07n09 (April 10, 2005): 1121–27. http://dx.doi.org/10.1142/s021797920502995x.

Full text

Abstract:

In this study, a magneto-rheological fluid dispersed by silica-coated iron was developed and its properties such as fluid viscosity (shear stress or shear rate) and abrasion were investigated. The metallic iron coated by silica dispersed in magneto-rheological fluid was prepared by H 2 reducing of precipitated magnetite ( Fe 3 O 4). Then, the magneto-rheological fluid (MR fluid) for the seal was prepared with silica-coated iron or carbonyl iron (HQ type; diameter of 1.6-1.9 10-6m) and two solvent oils i.e. silicon oil (SH200cv, 10000cSt) and CVT oil (T-CVTF, automobile transmission oil). It was observed that the MR fluid viscosity of CVT oil with HQ particles is lower in every fluid condition. Furthermore, the surface roughness of polyvinyl plate after abrasion test for MR fluid with silica coated iron and CVT oil as solvent was higher compared to the other types of MR fluids. The results indicated that carbonyl iron (spherical particles) and silica-coated iron particles dispersed in silicon oil are feasible to be used where the low abrasion in mechanics is required.

APA, Harvard, Vancouver, ISO, and other styles

49

Kang, Ensil, and Jihoon Lee. "Regularizing Model for the 2D MHD Equations with Zero Viscosity." Abstract and Applied Analysis 2012 (2012): 1–7. http://dx.doi.org/10.1155/2012/212786.

Full text

Abstract:

We consider the regularity of two dimensional incompressible magneto-hydrodynamics equations with zero viscosity. We provide an approximating system to the equations and prove global-in-time existence of classical solution to this approximating system. By using approximating system, a priori estimates for the equations can be justified.

APA, Harvard, Vancouver, ISO, and other styles

50

Gautam, Nisha, Gadipelly Thirupathi, and Rajender Singh. "Magneto-viscosity of hydrothermal synthesized Cu-Zn ferrite ferrofluids." AIP Advances 7, no. 5 (March 1, 2017): 056727. http://dx.doi.org/10.1063/1.4977759.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Magnets – Viscosity'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles