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Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The cavitation effect of lubricating film has a significant impact on the seal performance of hydrodynamic pressure mechanical seals.Kerosene-based magnetic fluid lubrication upstream pumping mechanical seal with inclined groove was taken as the research object.By considering the cavitation heat effect as well as the viscous temperature effect, the calculation model of lubricating fluid film was established to study the influences of working conditions and structural parameters on the seal performances using the volume fraction of gas phase in the liquid film as an indicator, and the results were compared with those based on the model only considering the viscous temperature effect. It is found that, due to the cavitation heat model considering the variation of saturated vapor pressure of liquid film medium with temperature,the opening force, leakage rate and volume fraction of vapor phase when considering the thermal effect of cavitation are smaller than the corresponding results when considering the viscosity-temperature effect only, but the variation regularity of each parameter is basically the same under the two conditions. The cavitation effect is enhanced by increasing the rotational speed and the groove diameter ratio, while the cavitation effect is weakened by increasing the inlet pressure, film thickness, radial angle and number of grooves. An increase in rotational speed, groove depth, radial angle, and groove diameter ratio will lead to an increase in leakage rate, while an increase in inlet pressure and groove number can improve sealing performance. [ABSTRACT FROM AUTHOR]

It is important to precisely polish the inner surface of medical-grade TA1 pure titanium capillary tubes in order to reduce sample residue and enhance capillary pipetting precision, ultimately improving the accuracy and reliability of in vitro diagnostic equipment. To address the subpar inner surface quality of TA1 capillary tubes and the challenges associated with titanium material polishing, a novel chemically-assisted magnetic compound fluid polishing method was proposed. This method combines oxidation and mechanical removal to efficiently and precisely polish the inner surface of the tubes. Experimental studies were carried out to examine the effects of iron powder mass, hydrogen peroxide concentration and malic acid concentration on both the material removal rate and the inner surface roughness, with the aim of determining the optimal polishing parameters. The study involved the examination of surface morphology and elemental changes on the inner surface of capillary tubes both before and after polishing. This analysis aimed to assess the overall impact of the polishing technique on the inner surface of pure titanium capillary tubes. The results indicated that following a 90-minute polishing process under the specified conditions of 2 mg of iron powder, a hydrogen peroxide concentration of 7.2% and a malic acid concentration of 6%, the surface roughness of the TA1 capillary tube decreased from Ra 675 nm to Ra 75 nm. In the well-polished area devoid of initial dents, the surface roughness reached Ra 19.5 nm, with a material removal depth of up to 28 µm. Furthermore, the original surface scratches were effectively eliminated, both the depth and width of dents were significantly reduced, and no additional elements were introduced during the polishing process. [ABSTRACT FROM AUTHOR]

In order to improve the surface quality of zirconia ceramic workpieces, the magnetic compound fluid polishing tool were utilized. This was done to lessen the material's surface roughness, minimize surface and subsurface damage. With a focus on the effects of magnet speed, processing gap, and abrasive particle size in the polishing fluid on surface roughness and material removal rate, a 3-factor, 3-level orthogonal test was created using Taguchi's method. The weights of each factor on the two evaluation indices were then analyzed using ANOVA. The best process parameter combination for surface roughness was 300 r/min for the magnet speed, 0.5 mm for the processing gap, and 1.25 µm for the abrasive particle size; the best process parameter combination for material removal rate was 400 r/min for the magnet speed, 0.5 mm for the processing gap, and 2 µm for the abrasive particle size. With these processing parameters, the surface roughness can reach up to 4.5 nm, and the material removal rate can reach up to 0.117 µm/min. The optimization effect is significant. The polishing prediction model was developed using a BP neural network that has been genetic algorithm optimized. The prediction error was 3.948 4%. [ABSTRACT FROM AUTHOR]

Due to the complexity of working conditions and physical fields, the clearance flow field of the magnetic fluid sealing device for the main shaft of hydraulic turbine has always been a difficult point in the research of magnetic fluid seal. To study the flow characteristics of magnetic fluid in the clearance of the magnetic fluid sealing device for the main shaft of a hydraulic turbine, a numerical model of the flow field in the seal clearance of the main shaft was established and verified through experiments. The influence of the seal clearance, the width of the pole tooth, the height of the pole tooth and the width of the pole tooth slot on the flow of the magnetic fluid was studied by numerical calculation. The results show that the magnetic fluid near the pole tooth is not affected by the structural parameters and basically remains stationary. When the seal clearance is less than 0. 6 mm, the magnetic fluid in the clearance basically does not flow. When the seal clearance exceeds 0. 6 mm, the magnetic fluid near the pole slot and permanent magnet increases with the increase of the seal clearance, and the speed increases linearly. The flow of magnetic fluid near the pole tooth slot and permanent magnet decreases with the increase of the width of the pole tooth, and the velocity decreases linearly at first, decreases sharply at the width of the pole tooth from 3. 0 mm to 3. 5 mm, and finally tends to be stable. With the gradual increase of the height of the pole teeth and the width of the pole tooth slot, the magnetic fluid flow near the pole teeth and the permanent magnet will weaken. The magnetic fluid velocity near the pole teeth and slots will decrease sharply at the the height of the pole tooth from 1. 0 mm to 3. 5 mm and the width of the pole teeth from 3. 0 mm to 12 mm and finally become stable, while the magnetic fluid velocity near the permanent magnet has been decreasing linearly. [ABSTRACT FROM AUTHOR]

To investigate the corrosion of metals in nano magnetic fluids under magnetic field conditions, a two-step method was used to prepare nano NiFe2O3 magnetic fluids. The corrosion rate of copper sheets in nano magnetic fluid media under magnetic field conditions was investigated using the gravimetric method, and the effects of different dispersants and their mass fractions, pH values, nano NiFe2O4 particle mass fractions, and magnetic field strength on the corrosion rate of copper sheets were analyzed. The experimental results indicate that both oleic acid and sodium dodecyl sulfate inhibit the corrosion of copper sheets. And the inhibitory effect of sodium dodecyl sulfate is better. The corrosion rate of copper sheets under alkaline conditions is lower than that under acidic conditions. The addition of nano magnetic particles promotes the corrosion of copper sheets to a certain extent. The magnetic field strength can improve the corrosion resistance of copper sheets in nano magnetic fluid media. As the magnetic field strength increases, the corrosion rate of copper sheets gradually decreases. [ABSTRACT FROM AUTHOR]

In order to realize the simultaneous measurement of magnetic field and temperature, a Mach-Zehnder interferometer based on sphere-thin core fiber-sphere sensing structure was fabricated. The double parameter sensing was studied by using magnetic fluid as the sensing structure external environment. When the external magnetic field and temperature change, the refractive index of magnetic fluid changes regularly, and the magnetic field and temperature can be measured at the same time. But the extinction ratio of the structure is poor, so a spherical-multi mode fiber-thin core fiber-sphere sensor structure is improved. The results show that the magnetic field and temperature sensitivity of the sphere-thin core fiber-sphere sensing structure obtained by single-peak demodulation are -0.0967 nm/mT and 0.0667 nm/°C, respectively. The improved sphere- multi mode fiber-thin core fiber-sphere structure has a good interference effect, and the magnetic field and temperature sensitivity are 0.1267 nm/mT and -0.1213 nm/°C, respectively. It has the characteristics of low cost, high sensitivity, noise resistance and good application. The research can provide reference for the design of magnetic field and temperature double parameter sensor. [ABSTRACT FROM AUTHOR]

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bearing is the property of Bearing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bearing is the property of Bearing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of South China University of Technology (Natural Science Edition) is the property of South China University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to research the sedimentation stability of water-based magnetic fluid, the sedimentation stability of water-based Ni0.5Zn0.5 Fe2O4 magnetic fluid at different pH values was studied, and the experimental phenomena were analyzed. The results show that when the mass fraction of OA (oleic acid) is 4%, the mass fraction of SDS (sodium dodecyl sulfate) is 3%, and the mass fraction of Ni0.5Zn0.5 Fe2O4 is 2. 5%, the magnetic fluid as-prepared has the best stability. When pH value is <7, the sedimentation stability of magnetic fluid decreases with the decrease of pH value, but the viscosity increases with the decrease of pH value. When pH is >7, the sedimentation stability of MHD decreases with the increase of pH value. The higher the temperature is, the better the dispersion is. The pH value has a certain influence on the thermal dispersion of the magnetic fluid. The pH value has an important influence on the magnetic field settling stability and magnetic viscosity of magnetic fluid. Under the action of constant or increasing magnetic fields, the settling coefficient and viscosity of magnetic fluid change with the change of magnetic field and pH value. [ABSTRACT FROM AUTHOR]

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

It is an important and effective means to use a pipeline internal robot driven by the pipeline′s own fluid and equipped with magnetic flux leakage detection equipment to carry out long-distance transmission pipeline detection.The principle of pipeline magnetic flux leakage internal detection, algorithm of defect magnetic flux leakage and driving force of internal detection robot were introduced.Through adaptability, speed control and magnetic flux leakage detection module design related to defect detection effect, the results of the above project were applied to practical industrial practice.The results show that the internal detection robot developed in this project has stronger detection adaptability and can further improve the detection sensitivity and resolution of defects, which can be popularized and applied in the industry. [ABSTRACT FROM AUTHOR]

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objectives: The Poincaré force related to the precession of Earth's axis is usually omitted in the solution of the dynamo equations as its effects are minimal. But in fact, the period of Earth's axial precession is still a term that is worth considering compared to the period of Earth's magnetic field reversal. Methods: This paper compares and analyzes different dynamo models with Ekman number and Rayleigh number by introducing Earth's axis precession velocity with a period of 25 960 years. Results: It is found that Earth's axial precession stabilizes the kinetic energy and magnetic energy fluctuation of spherical shell magnetic fluid in a smaller range than the benchmark dynamo, and increases the toroidal kinetic energy of spherical shell magnetic fluid by more than 10% - 20%, which leads to significantly accelerated westward drift rate of the magnetic field. Based on the magnetic field strength and magnetic Reynolds number at the core ⁃mantle boundary of those dynamos, it is found that the introduction of the precession item of Earth's axis makes magnetic energy more tend to kinetic energy conversion. And by comparing the core ⁃mantle boundary dipolarity, it is found that the introduction of the precession item will reduce the dipolarity. But for the dynamos in this article, the influence is not strong enough to make it become less Earth ⁃ like. Conclusions: From the comparison and analysis of the dynamo models, the introduction of Earth's axis pre⁃ cession would possibly change the dynamo model with a small Ekman number to a multipole dominant dynamo model. It can be inferred that the term of Earth's axis precession should be considered in more precise research of the numerical dynamo simulation for more. [ABSTRACT FROM AUTHOR]

The effect of magnetic particle volume fraction on the lubrication performance of ferrofluid solid-liquid interface was studied by molecular dynamics simulation. The ferrofluid model of Fe304 with volume fraction of 5%, 9.6% and 14.7% was established, and the ferrofluid solid-liquid interface lubrication model was constructed. The structure of the lubrication model was optimized and annealed, and the optimized model was simulated. The simulation results show that with the increase of the magnetic particle volume fraction, the friction coefficient is reduced, so the lubrication performance of the ferrofluid is improved. The friction coefficient of the ferrofluid with volume fraction of 14.7% magnetic particles is about 67% lower than that of the ferrofluid with the volume fraction of 5% magnetic particles. Based on the data of mean square displacement, kinetic energy, van der Waals potential energy and temperature change, the effect of magnetic particle content on the lubrication performance of ferrofluid was explored from a microscopic point of view, and the mechanism of the effect of magnetic particle content on the lubrication of ferrofluid solid-liquid interface was revealed. The results show that the increase of magnetic particle content will enhance the diffusion ability of molecules in the magnetic fluid, make some molecules in the magnetic fluid adhere to the surface of the solid layer, and form a penetration layer or diffusion layer with strong friction reducing and anti-wear, so as to improve the lubrication performance of the magnetic fluid. In addition, the increase of magnetic particle content will reduce the van der Waals force between molecules in the magnetic fluid, change the viscosity of the magnetic fluid, and enhance the thermal conductivity and heat transfer performance, so as to improve the lubrication performance of solid-liquid interface. [ABSTRACT FROM AUTHOR]

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the emergence of more and more emerging functional materials, magnetic nanoparticles become an ideal option. Tn recent years, the magnetic fluids synthesized by nano-Fes()i particles have become a research hotspot due to unique physical and chemical properties as well as the wide range of applications. The development and the preparation methods of different magnetic fluids are introduced in this study and several types of special magnetic fluids are discussed. Finally, the existing problems of preparation and application of magnetic fluids are proposed and the development prospects are predicted. [ABSTRACT FROM AUTHOR]

Copyright of Imaging Science & Photochemistry is the property of Imaging Science & Photochemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Beijing University of Technology is the property of Journal of Beijing University of Technology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Jilin University (Science Edition) / Jilin Daxue Xuebao (Lixue Ban) is the property of Zhongguo Xue shu qi Kan (Guang Pan Ban) Dian zi Za zhi She and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND:The 40Ar/39Ar dating of sericites is a very important method for constraining the age of deposits, but the purity of sericite remains a problem. The sericite aggregate acquired by the available separation and purification method commonly contains microline. For example, the content of microline obtained by the conventional magnet-heavy liquid method in this study is 0-28%, whereas the content of microline obtained by the conventional suspension method is 3%-45%. When the content of microline in the sericite aggregate exceeds 10%, it will directly affect the accuracy of dating. OBJECTIVES:To find a useful method to increase the content of sericite and decrease the content of microline while the grain size is not too fine to cause 39Ar recoil loss during the irradiation. METHODS:The purification effects of conventional magnetic separation-heavy liquid method and conventional suspension method are firstly investigated. The experimental results show that the purity of sericites obtained by the two methods are low, and the particle size of the conventional suspension method is irregular and cannot meet the requirements of dating. The ultrasonic disaggregation-suspension method was used to carry out conditional experiments on the microline-bearing sericite aggregates obtained by the magnetic separation-heavy liquid method. RESULTS:Using the ultrasonic disaggregation-suspension method, the content of sericite increased sharply while the content of microline decreased greatly. For example, the content of sericite for one experiment increased from 28% to 77% and the content of microline relative to sericite decreased from 12.5% to zero. The fraction of the grain size <1μm was above 95% and the smallest grain size was >0.356μm which was larger than 0.08μm estimated for the 39Ar recoil distance. Such grain size cannot obviously cause 39Ar recoil loss and did not have obvious effects on the age of middle to high temperature steps. CONCLUSIONS:When the content of microline relative to sericite in the sericite-bearing aggregates concentrated by magnet-heavy liquid method is more than 10%, the ultrasonic disaggregation-suspension method can be used to further increase the content of sericite and decrease the content of microline to improve the accuracy of 40Ar/39Ar dating. [ABSTRACT FROM AUTHOR]

A novel small-caliber safety and arming (S&A) device is proposed to improve the fuze performance of modern small caliber projectile within a limited space, for which the “locking” and “unlocking” properties of magnetorheological (MR) grease with/without the presence of magnetic field are used. Based on the principle of MR grease flow through an abrupt contraction-expansion under squeezed pressure, the delay time for arming the firing section was obtained. The delay time mathematical model of reflecting the factors, such as structure size and fluid elasto-viscosity characteristics, is further derived by analyzing the fluid dynamic and magnetic fields. Simulated and experimental results show that the modified local damping coefficient favors to reduce the maximum model error to 6.7%. A delay time range of 9-84 ms was successfully achieved by adjusting the physical parameters, including orifice diameter, spinning rate and particle concentration, etc. Owning to a wide temperature operation range and reliable working mechanism, the proposed MR grease S&A device is expected to have extensive application prospects in small and medium caliber fuze systems. [ABSTRACT FROM AUTHOR]

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, bilayered spherical model is used in magnetic fluids hyperthermia. The uniform magnetic field is generated by Helmuz coil for magnetic fluids hyperthermia. Electromagnetically induced heating and bioheat transfer for self-formed CoFe2 O4 magnetic fluids are numerical analyzed by the finite element analysis method. The temperature of tumor and healthy tissue first increased with time and then reached a stable value. The highest temperature was found in center of tumor and the temperature first decreased with the increasing distance to the center of tumor, and then kept a stable value. The temperature of healthy tissue was a security value and the desired effect of magnetic fluids hyperthermia was obtained in a suitable parameters. The larger the radius of tumor tissue was, the slower the temperature droped and the higher the stability temperature was. The drop rate of temperature was flat in tumor tissue, but reached a stable value in healthy tissue. The temperature increased with the increasing volume fraction of magnetic fluids in the center of tumor tissue. [ABSTRACT FROM AUTHOR]

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To effectively control the dispersion and avoid the aggregate of Fe3O4 nanoparticles in the water, the dispersion of Fe3O4 nanoparticles was investigated before and after ultrasonic bath in different concentration of NaCl solution. The experimental results showed that the dispersion of Fe3O4 nanoparticles was little of aggeregates in the 0.4 mol/L NaCl solution. Furthermore, the magnetic Fe3O4-10-Hydroxycamptothecin compounds were prepared by refining pH values of 10-Hydroxycamptothecin system, and then the Fe3O4-HCPT@SiO2 core-shell structural nanoparticles were prepared, of which the diameter of the composite nanoparticle is about 120 nm. The drug release process proves the feasibility of this preparation method. [ABSTRACT FROM AUTHOR]

Magnetic fluid seal is one of the most mature applications of magnetic fluid. It is found that the anti-pressure capacity of the static or dynamic magnetic fluid seal may rise over time. If it is a dynamic seal, the starting torque will increase. These phenomena are investigated through experiment. Then the concept of yield stress of magnetic fluid is introduced to explain qualitatively the phenomena. And the formulas of anti-pressure capacity and torque are improved. The results show that the yield stress of magnetic fluid is the main factor inducing the increase in the anti-pressure capacity and torque of magnetic fluid seal. The greater the yield stress is, the higher the anti-pressure capacity is, and the larger the starting torque is. The results provide a design basis to reduce the starting torque and improve the anti-pressure capacity of magnetic fluid seal. [ABSTRACT FROM AUTHOR]

In some special applications, especially in the military industry, a magnetic liquid sealing technique is needed to solve the problem of leakage in the large gap. To improve and verify the pressure capability of magnetic liquid seal with large gaps, a magnetic liquid sealing structure with multiple magnetic sources is designed. The sealing capability and self-healing capability of magnetic liquid seal with multiple magnetic sources with 0.4 mm, 0.5 mm, 0.6 mm and 0.7 mm gaps are investigated by using experimental methods. The relations between the experimental results of magnetic liquid seal with multiple magnetic source and the theoretical results of magnetic liquid seal with single magnetic source are analyzed. The results show that the sealing capability and self-healing capability of magnetic liquid seal with multiple magnetic source decrease with the increase in gap height; the pressure capabilities of magnetic liquid seal with multiple magnetic source are 4. 7 , 3. 8 , 2. 8 and 2. 5 times of that of a magnetic liquid seal with single magnetic source for four different sealing gaps. In addition, the magnetic liquid seals with large gaps and multiple magnetic sources have good self-healing capabilities. [ABSTRACT FROM AUTHOR]

A ferrofluid damper with simple structure is proposed. Dynamic model of the flow of the ferrofluid in the damper is built according to Newton's second law and the continuity equation. Combining this dynamic model with the oscillating energy of a elastic cantilever beam, the expression for logarithmic decay rates of the beam installed with the damper can be obtained, which are also measured experimentally using different dampers composed of magnets with different radius, different gaps between the shells and the magnets or ferrofluid with different saturation magnetization. The experimental results show good agreement with the predictions by the theory. We can also find that the damping effects are enhanced when the radius of the magnets increases and there exists an optimal gap between the shell and the magnet, using which the vibrating beam can attain its maximal logarithmic decay rate. [ABSTRACT FROM AUTHOR]

The magnetic hydrostatic equation and the magnetic hydrodynamics equation are investigated as a basic theory which lays the cornerstone for decoupled computation and application. The method used for decoupled computation is the Boundary-Step by step-Hand and hand Iterative Method. Under the effect of traveling wave magnetic field, the flux of magnetic fluid has a direct relationship with the rotating angle of magnetic pole of the permanent magnetic rotor which is used to produce traveling wave magnetic field. The flux increases with the enlarged rotating angle of the permanent magnetic rotor. The intensity of traveling wave magnetic field also influences the magnetic fluid flux. At the same rotating angle of the magnetic pole of permanent magnetic rotor, the flux increases with the strengthened magnetic field; the frequency of traveling magnetic field only affects the flow velocity of magnetic fluid, and it has no direct influence on the flux. [ABSTRACT FROM AUTHOR]