Attenuation and rheological analysis of magnetic field-induced responsiveness for the magnetorheological elastomer-based composite

2021 ◽  
Author(s):  
Longsheng Chen ◽  
qian Lv ◽  
yao Gong ◽  
Lili Zou
Keyword(s):  
Magnetic Field ◽  
Storage Period ◽  
Morphological Properties ◽  
Future Application ◽  
Magnetorheological Elastomer ◽  
Rheological Analysis ◽  
Cyclic Shear ◽  
Mr Effect ◽  
The Impact ◽  
Storage Temperatures

Abstract A novel self-supporting multi-layer magnetorheological elastomer-based (MRE-based) composite with large magnetic field-induced responsiveness has been designed and fabricated. We characterized its morphological properties, evaluated the impact of fabrication conditions on its field-induced responsiveness, investigated attenuation of its field-induced responsiveness under different storage temperatures along with time and analyzed this mechanism from the perspective of rheology. The results showed that the MRE-based composite had homogeneous dispersing of the magnetic fillers and a clear interface between different layers. The field-induced responsiveness of the MRE-based composite could be affected by the fabrication conditions, and it attenuated at different rates when subjected to different storage temperatures along with time; its attenuation period lasted a few days under room temperature while over one month under low temperature (4℃). The rheological analysis results indicated a long-term cross-linking process over the storage period along with the attenuation of field-induced responsiveness, which might lead to increasing elasticity (indicated by the loss factor tan δ) and rigidity (indicated by the storage modulus G') of the MRE-based composite along with the storage period. What's more, emerging feature of Payne effect could be found on MRE-based composite during cyclic shear, which indicated decline of the mechanical properties due to strain-induced inherent friction. On the other hand, the iron fillers in MRE layer could enhance the shear modulus and lead to MR effect (up to 187%) for the whole composite, which benefits to the magnetic field-induced responsiveness, due to the relative strengthen of the MRE layer against the assist layer. This work presents a better understanding on the attenuation of the field-induced responsiveness, which is important for the future application of the MRE-based composite.

Magnetorheological Elastomer Silicone-Based Containing Corroded Carbonyl Iron Particles

2018 ◽  
Vol 772 ◽  
pp. 51-55 ◽  
Author(s):  
Nor Azlin Nazira Abd Rahman ◽  
Saiful Amri Mazlan ◽  
Siti Aishah Abdul Aziz ◽  
Nur Azmah Nordin ◽  
Ubaidillah ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Carbonyl Iron ◽  
Dilute Hydrochloric Acid ◽  
Weight Percent ◽  
Iron Particles ◽  
Magnetorheological Elastomer ◽  
Magnetorheological Elastomers ◽  
The Matrix ◽  
Mr Effect ◽  
And Storage

In this study, magnetorheological elastomers (MREs) were synthesized using silicone rubber (SR) as the matrix element interspersed with 70 weight percent of corroded carbonyl iron particles (CIPs). The CIPs were corroded in dilute hydrochloric acid (HCl) for 4 hours. The rheological properties related to MR effect were experimentally examined in the absence and presence of magnetic field at various current using a rheometer. The experimental results depicted the MR effect of the MRE with corroded CIPs decreased one-half, 27% as compared to the non-corroded samples, 58%. The correlation between the purity of CIPs and storage modulus of MR elastomer is examined in this study.

Emergence of Twisted Magnetic Flux Related Sigmoidal Brightening

2000 ◽  
Vol 179 ◽  
pp. 263-264
Author(s):  
K. Sundara Raman ◽  
K. B. Ramesh ◽  
R. Selvendran ◽  
P. S. M. Aleem ◽  
K. M. Hiremath
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Magnetic Flux ◽  
Ultra Violet ◽  
Active Regions ◽  
Morphological Properties ◽  
Energy Storage And Conversion ◽  
The Sun ◽  
X Rays ◽  
The Magnetic Field

Extended AbstractWe have examined the morphological properties of a sigmoid associated with an SXR (soft X-ray) flare. The sigmoid is cospatial with the EUV (extreme ultra violet) images and in the optical part lies along an S-shaped Hαfilament. The photoheliogram shows flux emergence within an existingδtype sunspot which has caused the rotation of the umbrae giving rise to the sigmoidal brightening.It is now widely accepted that flares derive their energy from the magnetic fields of the active regions and coronal levels are considered to be the flare sites. But still a satisfactory understanding of the flare processes has not been achieved because of the difficulties encountered to predict and estimate the probability of flare eruptions. The convection flows and vortices below the photosphere transport and concentrate magnetic field, which subsequently appear as active regions in the photosphere (Rust & Kumar 1994 and the references therein). Successive emergence of magnetic flux, twist the field, creating flare productive magnetic shear and has been studied by many authors (Sundara Ramanet al.1998 and the references therein). Hence, it is considered that the flare is powered by the energy stored in the twisted magnetic flux tubes (Kurokawa 1996 and the references therein). Rust & Kumar (1996) named the S-shaped bright coronal loops that appear in soft X-rays as ‘Sigmoids’ and concluded that this S-shaped distortion is due to the twist developed in the magnetic field lines. These transient sigmoidal features tell a great deal about unstable coronal magnetic fields, as these regions are more likely to be eruptive (Canfieldet al.1999). As the magnetic fields of the active regions are deep rooted in the Sun, the twist developed in the subphotospheric flux tube penetrates the photosphere and extends in to the corona. Thus, it is essentially favourable for the subphotospheric twist to unwind the twist and transmit it through the photosphere to the corona. Therefore, it becomes essential to make complete observational descriptions of a flare from the magnetic field changes that are taking place in different atmospheric levels of the Sun, to pin down the energy storage and conversion process that trigger the flare phenomena.

INFLUENCE OF THE DIFFERENT SOIL PREPARATION METHODS ON THE PEA YIELD

2018 ◽  
pp. 16-20
Author(s):  
А. М. Grebennikov ◽  
А. S. Frid ◽  
V. P. Belobrov ◽  
V. А. Isaev ◽  
V. М. Garmashоv ◽  
...  
Keyword(s):  
Field Experiments ◽  
Morphological Properties ◽  
Mineral Fertilizers ◽  
First Year ◽  
Zero Tillage ◽  
Preparation Methods ◽  
Soil Preparation ◽  
Multifactor Analysis ◽  
The Impact ◽  
Central Chernozem

The article assesses the relationships between the morphological properties of agrochernozems and yield of peas on the plots, experience with different methods of basic treatment (moldboard plowing at the depth of 20 - 22, 25 - 27 and 14 - 16 cm, moldboard plowing to a depth of 14 - 16 cm, combined midwater moldboard, mid-water subsurface, surface to a depth of 6 - 8 cm and zero tillage) is inherent in V.V. Dokuchaev Research Institute of Agriculture of the Central Black Earth strip, in the fall of 2014. The research was conducted in 2015 - 2016, with the application of mineral fertilizers (N60Р60К60) and unfertilized background. The highest pea yields in the fertilized as the background, and without the use of fertilizers was observed in dumping plowing and especially in the variant with deep moldboard plowing, which creates in comparison with other ways of handling the best conditions for the growth and development of peas. The lowest yield of pea was obtained with zero processing. Apparently legalistic migrational-mizelial agrochernozems the Central Chernozem zone of minimum tillage in the cultivation of peas are not effective, what is evident already in the first year after the laying of experience with different basic treatments. As shown by the results of applying multifactor analysis of variance studied the mapping properties of the soil can have the same significant impact on the yield of agricultural crops, as options for the field experiments aimed at assessing the impact of various treatments on yield.

MAGNETIC FIELD IMPACT UPON TRIBOTECHNICAL CHARACTERISTICS OF PERMANENT CONNECTIONS IN RELATION TO FRICTION SHOCK ABSORBERS

2020 ◽  
Vol 2020 (10) ◽  
pp. 4-11
Author(s):  
Victor Tikhomirov ◽  
Aleksandr Gorlenko ◽  
Stanislav Volohov ◽  
Mikhail Izmerov
Keyword(s):  
Magnetic Field ◽  
Friction Factor ◽  
Physical Contact ◽  
Active Centers ◽  
Press Fit ◽  
Electro Magnetic Field ◽  
Investigation Methods ◽  
Electro Magnetic ◽  
The Impact ◽  
The Magnetic Field

The work purpose is the investigation of magnetic field impact upon properties of friction steel surfaces at fit stripping with tightness through manifested effects and their wear visually observed. On the spots of a real contact the magnetic field increases active centers, their amount and saturation with the time of dislocation outlet, and has an influence upon tribo-mating. The external electro-magnetic field promotes the increase of the number of active centers at the expense of dislocations outlet on the contact surface, and the increase of a physical contact area results in friction tie strengthening and growth of a friction factor. By the example of friction pairs of a spentonly unit in the suspension of coach cars there is given a substantiation of actuality and possibility for the creation of technical devices with the controlled factor of friction and the stability of effects achieved is also confirmed experimentally. Investigation methods: the fulfillment of laboratory physical experiments on the laboratory plant developed and patented on bush-rod samples inserted with the fit and tightness. The results of investigations and novelty: the impact of the magnetic field upon the value of a stripping force of a press fit with the guaranteed tightness is defined. Conclusion: there is a possibility to control a friction factor through the magnetic field impact upon a friction contact.

Method development for the determination of textural properties of sugar beet roots

2019 ◽  
pp. 392-400 ◽  
Author(s):  
Gunnar Kleuker ◽  
Christa M. Hoffmann
Keyword(s):  
Sugar Beet ◽  
Compression Test ◽  
Storage Period ◽  
Textural Properties ◽  
Small Sample ◽  
Root Tip ◽  
Flexural Test ◽  
Sample Distribution ◽  
The Impact

The harvest of sugar beet leads to root tip breakage and surface damage through mechanical impacts, which increase storage losses. For the determination of textural properties of sugar beet roots with a texture analyzer a reliable method description is missing. This study aimed to evaluate the impact of washing, soil tare, storage period from washing until measurement, sample distribution and number of roots on puncture and compression measurements. For this purpose, in 2017 comprehensive tests were conducted with sugar beet roots grown in a greenhouse. In a second step these tests were carried out with different Beta varieties from a field trial, and in addition, a flexural test was included. Results show that the storage period after washing and the sample distribution had an influence on the puncture and compression strength. It is suggested to wash the roots by hand before the measurement and to determine the strength no later than 48 h after washing. For reliable and comparable results a radial distribution of measurement points around the widest circumference of the root is recommended for the puncture test. The sample position of the compression test had an influence on the compressive strength and therefore, needs to be clearly defined. For the puncture and the compression test it was possible to achieve stable results with a small sample size, but with increasing heterogeneity of the plant stand a higher number of roots is required. The flexural test showed a high variability and is, therefore, not recommended for the analysis of sugar beet textural properties.

THE IMPACT OF A MAGNETIC FIELD ON THE WEAR OF THE GRINDING BODIES, LINING, AND ORE DISINTEGRATION (IN ENGLISH)

2018 ◽  
pp. 75-82
Author(s):  
KHOPUNOV EDUARD AFANAS'EVICH ◽  
◽  
SHATAILOV IURII LEONIDOVICH ◽  
VORONCHIKHIN SERGEI LEONIDOVICH ◽  
SHATAILOV ALEKSANDR IUR'EVICH ◽  
...  
Keyword(s):  
Magnetic Field ◽  
The Impact

scholarly journals X-ray Shielding, Mechanical, Physical, and Water Absorption Properties of Wood/PVC Composites Containing Bismuth Oxide

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2212
Author(s):  
Worawat Poltabtim ◽  
Ekachai Wimolmala ◽  
Teerasak Markpin ◽  
Narongrit Sombatsompop ◽  
Vichai Rosarpitak ◽  
...  
Keyword(s):  
Impact Strength ◽  
Water Absorption ◽  
Attenuation Coefficient ◽  
Bismuth Oxide ◽  
Morphological Properties ◽  
Linear Attenuation Coefficient ◽  
X Rays ◽  
Equivalent Thickness ◽  
X Ray ◽  
The Impact

The potential utilization of wood/polyvinyl chloride (WPVC) composites containing an X-ray protective filler, namely bismuth oxide (Bi2O3) particles, was investigated as novel, safe, and environmentally friendly X-ray shielding materials. The wood and Bi2O3 contents used in this work varied from 20 to 40 parts per hundred parts of PVC by weight (pph) and from 0 to 25, 50, 75, and 100 pph, respectively. The study considered X-ray shielding, mechanical, density, water absorption, and morphological properties. The results showed that the overall X-ray shielding parameters, namely the linear attenuation coefficient (µ), mass attenuation coefficient (µm), and lead equivalent thickness (Pbeq), of the WPVC composites increased with increasing Bi2O3 contents but slightly decreased at higher wood contents (40 pph). Furthermore, comparative Pbeq values between the wood/PVC composites and similar commercial X-ray shielding boards indicated that the recommended Bi2O3 contents for the 20 pph (40 ph) wood/PVC composites were 35, 85, and 40 pph (40, 100, and 45 pph) for the attenuation of 60, 100, and 150-kV X-rays, respectively. In addition, the increased Bi2O3 contents in the WPVC composites enhanced the Izod impact strength, hardness (Shore D), and density, but reduced water absorption. On the other hand, the increased wood contents increased the impact strength, hardness (Shore D), and water absorption but lowered the density of the composites. The overall results suggested that the developed WPVC composites had great potential to be used as effective X-ray shielding materials with Bi2O3 acting as a suitable X-ray protective filler.

scholarly journals Qualitative and quantitative assessment of magnetic vestibular stimulation in humans

2020 ◽  
Vol 30 (6) ◽  
pp. 353-361
Author(s):  
Rebecca S. Dewey ◽  
Rachel Gomez ◽  
Chris Degg ◽  
David M. Baguley ◽  
Paul M. Glover
Keyword(s):  
Magnetic Field ◽  
Objective Measure ◽  
Quantitative Measure ◽  
Vestibular Stimulation ◽  
Initial Study ◽  
Clinical Test ◽  
Healthy Control ◽  
Student’S T ◽  
The Impact ◽  
The Magnetic Field

The sensation of phantom motion or exhibition of bodily sway is often reported in the proximity of an MR scanner. It is proposed that the magnetic field stimulates the vestibular system. There are a number of possible mechanisms responsible, and the relative contributions of susceptibility on the otolithic receptors and the Lorentz force on the cupulae have not yet been explored. This exploratory study aims to investigate the impact of being in the proximity of a 7.0 T MR scanner. The modified clinical test of sensory interaction on balance (mCTSIB) was used to qualitatively ascertain whether or not healthy control subjects who passed the mCTSIB in normal conditions 1) experienced subjective sensations of dizziness, vertigo or of leaning or shifting in gravity when in the magnetic field and 2) exhibited visibly increased bodily sway whilst in the magnetic field compared to outside the magnetic field. Condition IV of the mCTSIB was video recorded outside and inside the magnetic field, providing a semi-quantitative measure of sway. For condition IV of the mCTSIB (visual and proprioceptive cues compromised), all seven locations/orientations around the scanner yielded significantly more sway than at baseline (p < 0.01 FDR). A Student’s t-test comparing the RMS velocity of a motion marker on the upper arm during mCTSIB condition IV showed a significant increase in the amount of motion exhibited in the field (T = 2.59; d.f. = 9; p = 0.029) compared to outside the field. This initial study using qualitative measures of sway demonstrates that there is evidence for MR-naïve individuals exhibiting greater sway while performing the mCTSIB in the magnetic field compared to outside the field. Directional polarity of sway was not significant. Future studies of vestibular stimulation by magnetic fields would benefit from the development of a sensitive, objective measure of balance function, which can be performed inside a magnetic field.

Probiotic Greek yogurt: effect of the addition of prebiotic fat substitutes on the physicochemical characteristics, probiotic survival, and sensory acceptance

2021 ◽  
Vol 88 (1) ◽  
pp. 98-104
Author(s):  
Sofia Sestito Dias ◽  
Damarys de Souza Vergílio ◽  
Arthur Marroni Pereira ◽  
Suellen Jensen Klososki ◽  
Vanessa Aparecida Marcolino ◽  
...  
Keyword(s):  
Negative Impact ◽  
Storage Period ◽  
Titratable Acidity ◽  
Physicochemical Characteristics ◽  
Modified Starch ◽  
Sensory Acceptance ◽  
Ph Values ◽  
Fat Substitutes ◽  
Gastrointestinal Conditions ◽  
The Impact

AbstractIn this research communication we evaluate the impact of the addition of prebiotic components (inulin, polydextrose, and modified starch, 40 g/l) as fat substitutes on the physicochemical characteristics, probiotic survival, and sensory acceptance of probiotic (Lacticaseibacillus casei 01, 108 CFU/ml) Greek yogurts during storage (7 °C, 28 d). All formulations had probiotic counts higher than 107 CFU/ml during storage and simulated gastrointestinal conditions (SGIC). The prebiotic components increased the probiotic survival to the enteric phase of the SGIC, with inulin producing the most pronounced effect. Inulin addition resulted in products with lower pH values and consistency and higher titratable acidity during storage, with negative impact on the sensory acceptance (flavor, texture, and overall impression) at the end of the storage period. Modified starch addition impacted negatively on the acceptance of the products (appearance, flavor, texture, and overall impression). Polydextrose addition resulted in products with lower consistency, but similar sensory acceptance to the full-fat yogurt. It can be concluded that it is possible to prepare potentially synbiotic Greek yogurts by desorption technique using L. casei as probiotic culture and inulin, polydextrose or modified starch as prebiotic components, with the utilization of polydextrose being advisable.

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