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The objective is to compare magnetic biochar derived from Wodyetiabifurcata seeds to biochar modified with H2SO4 in terms of their ability to remove Cr(VI) ions from synthetic wastewater. Research Tools and Procedures: The biochar was composed of carboxylated biochar obtained from Wodyetiabifurcata seeds and magnetic particles of Fe3O4-NaOH. A reagent for analysis was a 1.5 DPC solution, and a 1000 mgL stock solution of Cr(VI) was created. The purpose of this research is to examine how the adsorption capacities of Cr are affected by pH, concentration, and time (VI). A total of eight samples will be analysed in the investigation. The computations led to an 85 percent G power value. Findings: XRD, field scanning electron microscopy (FSEM), and transmission electron microscopy (FTEM) demonstrated that the magnetic particles were chemically bound to the biochar surface and dispersed uniformly over its surface. Compared to the initial carboxylated biochar, the magnetic biochar had a greater ability to adsorb Cr(VI) ions. Analysis using VSM and XPS showed that the biochar exhibited magnetic characteristics due to the connected magnetic particles, which also allowed for the binding of decreased Cr(III) cations. Results showed that the elimination of Cr increased with increasing pH and contact duration, as discussed in the research (VI). Even though the clearance rate was 99 percent at a pH of 2.0, the p-value was 0.701 (P>0.005), hence the finding was not statistically significant. The research also shown that a concentration of 50 mg/L enhanced the clearance % of Cr(VI). The results showed that the biosorbent had an estimated adsorption capacity of 16.74 mg/g. Based on these findings, it appears that magnetic biochar might be a viable option for treating wastewater that contains Cr(VI) in a practical manner. The maximum percentage of Chromium VI that may be removed by using Wodyetiabifurcata magnetic biochar is 99.4 percent. [ABSTRACT FROM AUTHOR]

Soft magnetic powdered materials are a specific group of materials of remarkable application potential, and they have been intensively studied by scientists to improve their magnetic properties. The shape, in which are usually these materials prepared (conventional sheets, crystalline ribbon prepared by rapid solidification technology etc.), is in many cases not suitable shape for industry applications. One of the ways to prepare material suitable for industrial applications (3-d material) is the compaction of powder, which can be produced by the mechanical milling of mixture of powders, thin ribbons, sheets, etc. The presented work describes the explanation of the influence of the mechanical milling of iron powder. The material prepared by mechanical milling exhibits excellent soft magnetic properties and they are usually part of the compacted material for different applications. [ABSTRACT FROM AUTHOR]

This study used magnetorheological (MR) foam which consist of carbonyl iron particles (CIPs) that were incorporated into a polyurethane foam. The polyurethane was fabricated using two different compositions of CIPs which were 35 and 55 wt.% to investigate the magnetostriction effect with different concentrations of magnetic particles. The magnetostriction of MR foams with influence of temperatures were investigated by using shear oscillatory rheometer that equipped with the temperature's controller applied at a specific temperature, with magnetic fields ranging from 0 to 0.7T. Based on previous research, MR foam has been found to expand in the presence and strength of magnetic fields. However, the magnetostriction of MR foams under different operating temperatures are not yet discovered since it causes changes in its behavior and performance. Therefore, the purpose of this study is to analyze the magnetostriction of MR foams at different operating temperatures between 25 to 50°C, with 5°C increment. The finding revealed that the mag-netostriction has slightly decreased at temperatures between 25 to 40°C. Nevertheless, at temperature between 40 to 50°C, the magnetostriction some-how increased for both MR foam samples. In fact, the magnetostriction for MR foam with 55 wt.% concentration of CIPs achieved higher compared to MR foam with 35 wt.% concentration of CIPs, by about 26.56% particularly at 25°C. Prior to the application of MR foam in sensors and actuators that would experience induced of heat during the operating system, it is crucial to understand the behaviors of MR foam as well as the magnetostriction under different operating temperatures. [ABSTRACT FROM AUTHOR]

A novel type of magnetorheological (MR) foam that provides unique porous structure with embedded magnetic particles somehow could response to magnetic field stimuli continuously, actively and reversibly. Its low density and controllable properties have rendered MR foam to be a new potential smart material for advance applications such as smart actuators or sensors technology. Unfortunately, the rheological properties in terms of stiffness or known as storage modulus of MR foam is still rather limited, in the range of below than 1 MPa to withstand frequencies with high amplitude displacement during the operational system. Therefore, the aim of this research is to enhance the rheological properties of MR foam in terms of storage modulus by adding silica nanoparticles as an additive. In this study, MR foams were fabricated with different compositions of silica nano-particles in the range of 0 to 5 wt.%, with 1 wt.% increment. The rheological testing was carried out using modular compact rheometer (MCR) under different frequency inputs in the range of 1 to 10 Hz, with the absence and presence of magnetic field at 0 T and 0.8 T, respectively. The finding has revealed that the storage modulus of MR foam has significantly increased up to ∼273% during the off-state condition and further increased to ∼346% at the on-state condition, indicating higher stiffness of MR foam with silica nanoparticles as compared to non-additive MR foam. [ABSTRACT FROM AUTHOR]

Magnetorheological (MR) material is a smart material composed of one of the magnetic particles of carbonyl iron (CIP) in a non-magnetic medium that can be controlled via magnetic fields. One of the groups of MR materials is MR plastomer (MRP) which consists of CIPs in the low-crosslinking polymer network such as plastomer, and it is introduced to compromise the limitations in MR fluid and MR elastomer. Somehow, the new modern approach particularly machine learning needs to be highlighted to acquire accuracy in the prediction trend of the MRP's properties, including viscosity. In fact, the approach may reduce time and work consuming in the development process of MRP. Therefore, using an artificial neural network (ANN) as one of the machine learning approaches is an effective medium for forecasting the behavior of the material and resolving constitutive model concerns. [ABSTRACT FROM AUTHOR]

Different fabrication process would result to different properties of material. This is due to the properties of porous materials are highly dependent on its structure. In this study, magnetorheological (MR) foam was prepared via two fabrication processes, namely open mould system and constraint volume mould system which was also known as open-mould (O-MRFoam) and closed-mould system (C-MRFoam), respectively. The characteristics and properties of the fabricated MR foam were presented in this paper. The characteristics of MR foam such as morphological and rheological behavior in terms of storage modulus and linear viscoelastic (LVE) region were experimentally investigated. It can be seen that the properties of MR foam were affected by different fabrication processes. In terms of morphological observation, the average area of pores decreases by 39% when a constraint volume mould system was implied to the fabrication process of the MR foam. It is believed that the distribution of magnetic particles become more compact resulting to more bubble nucleation during the foaming process. As a result, the storage modulus of MR foam was successfully enhanced along with the decrement of the size of pores. Therefore, the results obtained from this study would widen the potential MR foam especially for the use of applications with controllable stiffness. [ABSTRACT FROM AUTHOR]

MR foam is a magnetically permeable solid material that composed of micron-sized magnetic particles known as carbonyl iron (CIPs) that are embedded in a porous absorbent matrix of foam. There are two types of methods to fabricate MR foams known as ex situ and in situ methods. In particular, the methods related to the location of CIPs in the structure of MR foams such that in situ MR foam contained of CIPs in the struts of foam. Meanwhile, ex situ MR foam contained of CIPs in the pores of foam rather than in the struts structure. Correspondingly, resultant magnetostriction of each type of MR foam would be different as magnetic responsiveness of MR foams towards the applied magnetic fields would be differ as well. Therefore, three MR foams were fabricated via three methods particularly, ex situ, in situ, and hybrid as a combination of ex situ and in situ methods. Then, the samples underwent the magnetostriction test at various magnetic fields from 0 to 0.8 T using a rheometer that equipped with electromagnetic device. The results show that the hybrid MR foam exhibited the highest magnetostriction, about 36.74%, followed by ex situ- and in situ MR foams. It is attributed to the CIPs that were located in the struts and pores of MR foam which result in a stronger magnetic force between the particles, and towards the applied magnetic fields. [ABSTRACT FROM AUTHOR]

The magnetic abrasive machining (MAM) technique is a well-developed unconventional machining technique. In the manufacturing industry, magnetic abrasive particles (MAP) and the magnetic force required to apply in the machining zone are commonly used in the nano-range for surface finishing of workpieces. It is more precise and faster than traditional methods, and it can produce finished components that are defect-free. This paper illustrates the development of an experimental setup for performing MAF operations on a flat A681 high carbon steel plate. Effect of working gap, rational speed, and abrasive particle size on change in surface roughness and material removal have been studied. Taguchi's L12 design of experimentation technique was used to plan the experiments. After each experiment, we calculated improvement in the surface finish and material removal. The result showed that, the highest improvement value of average surface roughness (ΔRa) was 0.066 µm (56.89 %) at 150 rpm, 1.5 mm gap, 35 µm abrasive particle size. The lowest value of ΔRa was as 0.09 µm (11.11 %) at 360 rpm, 1.5 mm gap, 400 µm abrasive particle size, the highest value of material removal (MR) was 0.026 g at 360 rpm, 1.5 mm gap, 400 µm abrasive particle size. [ABSTRACT FROM AUTHOR]

Serial number restoration refers to scientific techniques of retrieving or restoring a damaged manufacturer's identification. Various techniques have been demonstrated to restore the identification in the literature re-view. However, a non-destructive method is preferable in forensic analysis. The main objective of this paper is to review a few contemporary techniques to restore obliterated serial numbers on vehicles and firearms. Magnetic particle inspection is preferred among these methods due to its effectiveness and portability. [ABSTRACT FROM AUTHOR]

Structural and magnetic properties of greenly synthesized sugar coated Li0.1Fe2.9O4 nanoparticles (LFO NPs) have been investigated. Formation of phase pure sugar coated ∼17nm sized LFO NPs in simple cubic symmetry is affirmed by PXRD, Raman and FTIR analysis. The difference in average crystallite size (∼17nm) and size of magnetic particle (∼15nm) also establishes the sugar coating on the LFO nanoparticles. S-shaped M-H curve fitted with Langevin function revealed that sugar-coated LFO NPs exhibits superparamagnetism with a high saturation magnetization of 72emu/g (∼2.93 µB/f.u.) at room temperature. Surface functionalization via sugar coating and excellent saturation magnetization makes LFO NPs suitable for biomedical applications. [ABSTRACT FROM AUTHOR]

This work reports assessment of a failure of a cold forged gear blank reported from an industry. The damage is observed in the cold forged in form of cracks along the thickness direction. To investigate this problem, the visual examination, composition analysis, hardness, microstructure, residual stress measurement and non-destructive tests such as magnetic particle inspection, ultrasonic detection and radiographic tests were carried out and analyzed. The detailed comprehensive investigation revealed that the crack has occurred in the initial stage itself and acceptance criteria of the material to be evolved. The same has been discussed with the end user to ascertain that this type of failure should not occur again. [ABSTRACT FROM AUTHOR]

Several methods have been developed to achieve desired magnetic nanoparticles and their functionalization. The mixing method during the reaction process becomes one of the parameters that affect the product characteristics. In this research, magnetic-silica (MAGSi) particles were fabricated via different methods: conventional stirring, probe sonication, and bath sonication. The phase, functional group, size distribution, morphology, and magnetic properties of the particles were characterized. The phase and functional groups data show no difference, while the sizes distribution and the electron-microscopy data show that sonication gives a more homogeneous particle size distribution (500 nm) and lowers agglomeration tendency. However, the thicker silica surface impacts the low magnetic saturation of sonication samples with 58, 15, and 14 emu/g for conventional stirring, probe sonication, and bath sonication, respectively. Further, a preliminary experiment of adsorption-desorption of DNA on the MAGSi particles was done. The electrophoresis and spectroscopy data show all MAGSi particles can be used for DNA adsorption-desorption. [ABSTRACT FROM AUTHOR]

The uncertainties in particle velocity and position-time data collected using embedded magnetic gauges are presented. Data were also collected on the resistance change of gauge elements under shock loading and the effect of the element width, as opposed to length, on the observed rise times, as two factors that can affect the data quality and uncertainty analysis. A new method of fitting to the shock tracker data using cubic smoothing splines is also proposed. The data were collected using gas gun experiments on Comp-B and Polychlorotrifluoroethylene (PCTFE) targets. For a well characterized setup, the uncertainty in the particle velocity data can be reduced to such a level that noise and other 'random' variations in the data can be more significant. This highlights the importance of reducing these factors and collecting high quality data but also investigating additional sources of error, such as the resistance change of the elements under shock loading, in order to determine the true uncertainty. [ABSTRACT FROM AUTHOR]

This talk considers the numerical treatment of the differential equation that describes the motion of electric particles in a strong magnetic field. A standard integrator is the Boris algorithm which, for small stepsizes, can be analysed by classical techniques. For a strong magnetic field the solution is highly oscillatory and the numerical integration is more challenging. New modifications of the Boris algorithm are discussed, and their accuracy and long-time behaviour are studied with means of modulated Fourier expansions. Emphasis is put on the situation where the stepsize is proportional to (or larger than) the wavelength of the oscillations. [ABSTRACT FROM AUTHOR]

Polluted water that contains heavy metals, especially lead [Pb(II)] and copper [Cu(II)] could cause many health issues which could be controlled by adsorption. Magnetically modified watermelon rind (MMWMR) were successfully made to adsorb Pb(II) and Cu(II) in synthetic wastewater. Watermelon rind is modified with Fe2O3 at several variation of ratios [1:1, 1:2, 1:3, 1:4, and 1:5 (w/w)] and conducted in several variation of dosage [0.5, 1.0, 1.5, 2, 2.5 grams] and temperature [30°C, 40°C, 50°C, and 60°C]. Adsorbents are characterized by FTIR and AAS. The analysis results showed that modifying watermelon rind with magnetic particles has a very good potential for the development of low-cost bio sorbent. MMWMR has a potential to adsorb Pb(II) and Cu(II) well with in modifier ratio 5:1 at 60°C, the adsorption removal are 98% and 96%, respectively. [ABSTRACT FROM AUTHOR]

Ferrogels are functional materials where a soft gel matrix is filled with ferromagnetic and usually nanosized particles. Such composition provides opportunity to tune the mechanical behavior of ferrogels by an external magnetic field. This feature along with a biocompatibility of material components makes ferrogels prospective for utilization in various bio-medical applications. We propose a model of the small ferrogel sample on the basis of the coarse-grained molecular dynamics approach. The material is represented as an ensemble of spherical objects of two types (magnetic particles and polymer "blobs") bound by Lennard-Jones interaction and partly interlinked by elastic bonds. The latter are established during the initial stage of calculation, which provides a coherent and, at the same time, random internal structure of the sample. There is performed test simulation of the response of model samples with different concentrations of a magnetic filler on the external magnetic field and uniaxial mechanical load. [ABSTRACT FROM AUTHOR]

Soft magnetic materials (SMMs) are widely used in many industries, for example, in conventional transformers (where electric steel is used) as well as cosmology or medicine [1-2]. The elements such Fe, Ni, Co and their alloys can be included into SMMs. Permalloy (Fe-Ni), Supermalloy (Fe-Ni-Mo) and their modifications are widely known [3]. Depending on the way of their preparation they can be divided into two main groups: soft magnetic compacts or soft magnetic composites. Soft magnetic compacts are made by compacting ferromagnetic powder without adding any insulation, so it is conventional soft magnetic material but in the desired shape. Soft magnetic composite materials are progressive materials which are made from ferromagnetic insulated and compacted powder. The aim of this work was the investigation of the possibility for optimalization of magnetic properties of the powdered compacts. Mechanical milling leads to the decrease of powder size elements and on the other hand introduces structural defects of the material strongly negative affected magnetic properties of the compacts. One of the important aspects is determination of optimum conditions for mechanical milling, as ball to powder ratio (BPR) and milling time. By investigation of three samples of pure iron powder particles prepared by different ball to powder ratio has been detected that the most suitable magnetic properties exhibit the sample milled for BPR 9:1. [ABSTRACT FROM AUTHOR]

Soft magnetic compacts and composites are an important group of soft magnetic materials prepared by powder metallurgy methods. Although they have been known to researchers and manufacturers for over a century, emerging new technologies continue to enable their development. The study of the influence of imperfections in the shape of particles has proved that they have a substantial impact on the mechanical properties of the final product. Rough surfaces also present an obstacle to the displacement of domain walls in ferromagnets. This paper describes the effect of the process of mechanical surface treatment of powder particles on the magnetic properties of the resulting compact. The conclusions are based on the study of four samples formed from iron-based powders that have been subjected to a treatment process designed to smooth the surface and reduce impurities. [ABSTRACT FROM AUTHOR]

Soft magnetic compacted powder materials represent a specific material class with remarkable application potential, exhibiting excellent magnetic properties as low core losses, high permeability and 3-D isotropic magnetic behavior. They are intensively studied by physicists, chemists and materials scientists with an effort for further improving the magnetic properties of these materials. However, the ferromagnetic particles surfaces of the porous structure of powder compacts are responsible for the arise of inner demagnetizing fields which negatively affect the magnetic permeability. The demagnetizing field reduces the value of the internal magnetic field in compacted material and causes the reduction of the permeability value of the compact. The article describes the calculation of the influence of inner demagnetization factor on the decrease of permeability of the compact in comparison with the permeability of the powder particles. The resulting calculation was verified on two different compacts prepared from iron powder, one of which having particles with surfaces smoothed by an innovative method that removes sharp edges of powder particles and contaminated layers. [ABSTRACT FROM AUTHOR]

Research reveals the results of welding carbon steel with SMAW position 3G in the Diploma IV Mechanical Engineering Study Program. The welding results of students were tested using the Liquid Penetrant Testing and Magnetic Particle Testing methods by ASME standards. This research uses quantitative descriptive research to explain the facts. The sample used is the workpieces of student practice, totalling 25 workpieces. The results of this study explain that there are still many defects in student workpieces that result in not passing the welding results when tested using Liquid Penetrant and Magnetic Particle methods with ASME standards. Most defects are found on the surface of the workpiece, such as cracks, porosity, undercuts, lack of penetration. Welding defects found in the practice results indicate that students' experience, knowledge, and competence in welding are still low and need improvement. [ABSTRACT FROM AUTHOR]

This research continues previous research on non-destructive test welding results with visual test methods. The purpose of this study is to analyze the level of test clearance, the number of welding indications, and the cause of indications from the results of welding students of 3G Shielded Metal Arc Welding (SMAW) positions with magnetic particle test methods based on American Welding Society (AWS) and The American Society of Mechanical Engineers (ASME) standards. This research method uses descriptive research with a quantitative approach—the number of samples used as many as 25 students majoring in engineering education. The object of this study is the result of welding the students with SMAW welding machine position 3G and carbon steel material (mild steel). Data collection methods use instruments from AWS and ASME as well as documentation. The data that has been collected is then analyzed and transcribed based on existing facts. The results showed that many objects from student welding escaped if tested using magnetic particle methods. The level of independence is based on AWS standards to 20 students, while based on ASME standards, as many as 12 students. The most significant number of indications on student welding workpieces is rounded. The cause of the many indications that appear is due to improper preparation of the workpiece and incorrect selection of welding parameters such as inappropriate currents, welding speed, and inconsistent welding angles. [ABSTRACT FROM AUTHOR]

Nanoparticles such as gold, quantum dots and magnetic Nano particle possess exclusive size and shape dependent optoelectronic properties. In current ages, these sole properties have attracted much attention in the biomedical field and drug delivery system.The optical behavior of quantum dots, gold nanoparticle and magnetic nanoparticle can be tuned by their high brightness, size and high surface-to-volume ratio make them excellent candidates for imaging, and therapeutic delivery. In this review we discuss recent advances and challenges of nanoparticle and their biomedical applications. [ABSTRACT FROM AUTHOR]

Permanent magnets of the Fe – Nd – B system are widely used in technology for their production, methods of powder metallurgy are often used for powder obtained by quenching from a liquid state. The most optimal magnetic properties are characteristic of a nanocomposite system of grains of the main hard magnetic phase and an iron-enriched soft magnetic phase. The maximum values of the remanent induction of the magnet are achieved by texturing, i.e., by arranging the magnetoanisotropic grains of the main magnetic phase so that the directions of their axes of easy magnetization are co-directed. To inhibit the development of the domain structure inside the grains, it is necessary to create a certain microstructure, which prevents nucleation and movement of domain walls. For this, additional processes are performed that cause rearrangements in the microstructure. As a rule, such processes are accompanied by a high temperature close to the melting temperature of the intergranular phase. The article considers such additional effects on the microstructure as annealing (at 500-650 °C), hot pressing and hot deformation, spark pressing or hybrid sintering in an electric field and laser treatment. [ABSTRACT FROM AUTHOR]

The goal of this paper is to investigate the theoretical effects of a ferrofluid lubricated with couple stress fluid on a curved circular plate in a magnetic field. Further combining the Shliomis model for magnetic particle rotation, magnetic moments, and fluid volume concentration with the Stokes model for couple stress fluid.The modified Reynolds equation is obtained and the results for the film squeeze performance is presented. It is observed that result is more prominent for non-Newtonian ferro fluid as compared to Newtonian non-ferro fluid, also effect volumetric concentration of particles and Langevin parameter enhances the squeeze film characteristics. Further, it is found that the squeeze film pressure, load carrying capacity and response time is more pronounced for concave plate (β*˂0)in.comparison with convex plate (β*˃0) [ABSTRACT FROM AUTHOR]

Properties of magnetic nanoparticles arrays embedded in nonmagnetic insulator or semiconductor substrates are considered. employing the band structure based shell model for a nanoparticles. We show that such systems display ferromagnetic coupling leading to a superferromagnetic structure properties. Superferromagnetic structures are studied accounting for quantum fluctuations due to the discrete level structure and disorder within the randomly jumping interacting states model. The occurrence of self-organized criticality is found to indicate an existence of spinodal regions and critical points in superferromagnetic state equation and phase diagram. The magnetodynamics show jerky behaviour displayed as erratic stochastic discontinuities for magnetic induction. Magnetic noise correlations are proposed as model-independent analytical tools employed in order to specify, quantify and analyse magnetic structure and origin of superferromagnetism. We briefly overview some results for a sensor mode of SFM reactivity associated with spatially local external fields, i.e., a detection of magnetic particles. Favorable designs of superferromagnetic systems for sensor implications are revealed. [ABSTRACT FROM AUTHOR]

The use of new lubricants (modified magnetic fluids containing nanodispersed magnetic particles) in friction units of machines and mechanisms makes it possible to increase their reliability, quality and expand their functionality. In order to predict the operational properties of friction units lubricated with magnetic oil, the specific physicochemical features of the processes occurring on solid surfaces after applying a magnetic lubricant have been studied in detail. The energy changes occurring on the surface after applying magnetic oil to it were evaluated from the work function of electrons. The dynamics of change in the contact potential difference between metal surfaces lubricated with magnetic oil and its components has been studied. It is shown that the lubricating properties of the studied liquids correlate with the magnitude of the change in the contact potential difference after their application. In general, the contact potential difference between surfaces lubricated with magnetic oils is higher than those lubricated with a dispersion environment of magnetic oils. Using a two-component magnetic oil, the effect of dispersed magnetite particles on the work function has been studied. Particles of magnetite adhere to the surface under the action of van der Waals or dipole interaction and partially screen it. It follows from the data obtained that the addition of magnetic particles to the liquid of triethanolamine does not lead to a significant change in the work function in the entire time range. At the same time, magnetite particles covered with a layer of adsorbed fatty acid molecules increase the work function of electrons. Based on a large amount of empirical data, it can be qualitatively concluded that the work function of the sample surface from a magnetized material, which is covered with magnetic oil, stabilizes faster than for the surface of a demagnetized sample. It is not possible to quantify this difference due to the low reproducibility of the results. [ABSTRACT FROM AUTHOR]

This study presents the latest technology to produce axial induction motors for application in electric vehicles. A review of current state-of-the-art technology is performed on the solutions with soft magnetic powder core or machined parts that are not appropriate for mass production. Therefore, new technology is proposed, based on analyzed production technologies specifics. It involves use of a standard metal strips to make both stator and rotor cores. This design includes a spirally wound strip of magnetically conductive material and stacked trapezoidal lamellas. The trapezoidal lamellae are cut using waste-free technology for e.g., guillotine, without specialized punches as in traditional engines. As a result, metal cutting operations are significantly simplified and require widely used production equipment in the industry. The developed technology is appropriate for mass production due to its relatively low cost and eases adaptability. The proposed design is at the physical prototyping and testing stage. Thus, it will be validated by testing the physical prototype in the real industrial environment. This innovative technology is patented and currently under commercialization. [ABSTRACT FROM AUTHOR]

The effect of hydrogen pressure on kinetics of hydrogen-induced direct phase transformation in the industrial Nd2Fe14B type (R36.4Fe62.45B1.15, where R Nd, Pr, Ce, Dy) hard magnetic alloy for powder permanent magnets has been studied. It has been determined that, as the hydrogen pressure increase, a direct phase transformation significantly accelerates. It has been shown that the kinetics of direct phase transformation controlled by the Fe atoms diffusion and that the rate growth of new Nd2Fe14B phase increase with increase of initial hydrogen pressure. On the base of the Kolmogorov's and Lyubov's kinetic models the kinetic equation for describing of hydrogen pressure influence on the kinetic of this transformation in Nd2Fe14B type alloys has been presented. [ABSTRACT FROM AUTHOR]

Mesoporous magnetic silica (MMS) particle can be developed as a material for theragnostic-agent. It can offer therapeutic ability through hyperthermia treatment and drug-carrying possibility, while the magnetic particle can also be expected as an MRI contrast agent for diagnostic purposes. An effective MMS theragnostic agent should have high magnetic moment, small size and high surface area. In this work, MMS was synthesized with a variation of the magnetic and silica ratio. The magnetic nanoparticle was synthesized first through the co-precipitation method. The synthesize of MMS was conducted with two variations of magnetic and silica ratio (MMS 1:1 and 2:1) and the porous system was formed during hydrolysis of CTAB at the controlled sintering process. The samples were characterized using FTIR, XRD, VSM, PSA, and nitrogen adsorption-desorption. The MMS 2:1 result shows a larger particle size (more than 300 nm), lower magnetic moment (25 emu/g) compared to the MMS 1:1 (less than 300 nm in particle size and 35 emu/g for the magnetic moment). The nitrogen adsorption-desorption isotherm profiles confirm the formation of a mesoporous structure with nearly the same pore diameter for the two samples but a higher surface area for MMS 1:1. Further analysis should be done to confirm the magnetic nanoparticle position the formation of the mesoporous structure of the materials. [ABSTRACT FROM AUTHOR]

In this work, magnetite (Fe3O4) was derived from mill scale has been used as a potential scavenging agent in wastewater treatment due to its high adsorption capacity and its shorter sedimentation time during wastewater treatment. The Fe3O4 obtained from the mill scale oxidation reaction method by milled using High Energy Milling (HEM) to produce homogeneous of powder size under 400 mesh. The mill scale powder then calcined at temperature 300 °C for 0.5, 1 and 2 hours, with graphite addition to produce CO2 as an oxidant agent. The X-ray diffraction (XRD) test were performed to study the characteristic and purity of the obtained powder, vibrating sample magnetometer (VSM) to study the magnetic properties of the powder, and particle size analyzer (PSA) to know the distribution particle size of oxidation mill scale powder. The Fe3O4 powder then mixed and separated with dye solution with ratio of 1 : 5 vol.% by centrifuge process to know the magnetite powder adsorption characteristic. The clear part of the solution (treated wastewater) was filtered out and adsorption efficiency of Fe3O4 powder was compared and observed by manual photograph. [ABSTRACT FROM AUTHOR]

Nano-Crystalline powder of 0.6BiFeO3−0.4PbTiO3 solid solution was synthesized by sol-gel method. It is already being reported that bismuth ferrite (BiFeO3) is one of the most favourable multiferroic materials which show Curie temperature and Néel temperature, both are well above the room temperature. This raise the possibility of developing new kinds of devices based on coupling of magneto-electric at room temperature. The magneto-electric coupling is an interesting phenomenon where cross-coupling exists between electric and magnetic interactions. This kind of coupling is very important from the applications point of view for developing new generation multifunctional sensor, actuator and data storage devices. The synthesis has been successfully achieved by using maleic acid as chelating agent. The calcinations of gel at 550 °C yielded pure BF-0.4PT powders, with average particle size of 40 nm as determined using scanning electron microscopy (SEM). Rietveld analysis of room temperature x-ray diffraction data of BF-0.4PT shows that the system has two tetragonal phases with tetragonality of 8.82% and 1.18%. Room temperature M-H measurement reveals exchange bias of ~100 Oe, which confirms core-shell type structure present in nano BF-0.4PT powder. [ABSTRACT FROM AUTHOR]

Electro-magneto-hydrodynamic flow of non-Newtonian fluid (blood) suspended with magnetic particles (erythrocytes) through tapered stenosed inclined artery is explored in this study. The fluid is influenced by a pulsatile constant pressure gradient and an inclined magnetic field. Governing partial differential momentum equations are solved and the fluid and particles axial velocity formula is derived in the analytical form. Further, closed form expressions are obtained for wall shear stress, flow resistance and volumetric flow rate. Graphical analysis of various physiological dynamics against embedded parameters is developed by MATLAB coding. Effects of pertinent parameters are examined and results are discussed. It is noted that both fluid and particle velocity profiles are reduced with increasing values of Hartmann number. In contrast, the electrokinetic number increases the velocities of the fluid and particle. Thus, the fluidic flow can be regulated by applying strong and adequate electromagnetic field which plays a vital role in diagnosing cardio vascular diseases and the respective medical care. [ABSTRACT FROM AUTHOR]

The possibility of synthesizing Fe-Cr-Co powder magnetic materials with low and medium cobalt content (8 to 16%) at a low sintering temperature of 1100 °C is shown. The relative density of the sintered specimens after sintering is about 94%. When the cobalt content in the material is 8%, the alloy is single-phase (α-phase). With an increase in the cobalt content to 16%, faint traces of the γ-phase (about 1%) appear. The magnetic hysteresis characteristics of the synthesized specimens are measured, and they have values that are acceptable for practical use according to GOST 24897-81. The functional properties of the obtained materials at a low sintering temperature of 1100 °C are compared with the properties of materials sintered at temperatures of up to 1400 °C. [ABSTRACT FROM AUTHOR]

This work deals with theoretical approach and mathematical modeling of hyperthermia effect by single– domain ferro-nanoparticles. The magnetic particles have the Neel relaxation particles of the easy magnetization axes. The system is happened under external magnetic field. Two situations of systems, system of approximation of non-interaction chaotic particles like single particle and system of chain-like two particles are considered into account whereas these particles are in strong magnetic anisotropy. Our analysis shows the chain of particles with strong magnetic anisotropy weakens the thermal effect of hyperthermia under the effect of easy magnetization axes of ferro-nanoparticles. [ABSTRACT FROM AUTHOR]

Nano-zircon-reinforced poly (methyl methacrylate) (n-Z/PMMA) composites were prepared using a liquid mixture approach and their tensile storage moduli were investigated using a dynamic mechanical analyzer (OMA). The effect of the n-Z concentration, i.e., 1, 2.5, and 5 wt%, on the storage moduli of the PMMA-based composites was the focus of this work. The n-Z powder was synthesized from natural zircon sand from Kereng Pangi, Central Kalimantan. The natural zircon sand had been extracted to give pure zircon powder by magnetic separation, milling, leaching with HCl 2M, and reacting with NaOH. XRO patterns confirmed the formation of a single phase of zircon. A quantitative analysis of XRO data of 15h-milled zircon powder showed that the crystallite size of the zircon powder reduced to 33±1 nm (n-Z). The PMMA/n-Z composites were prepared by mixing the melted polymer and the n-Z powder at the desired concentration. OMA measurement was carried out to characterize the storage modulus of the composites. Results showed that the maximum storage modulus was reached by the composite with n-Z of 5 wt%. The composite exhibited storage modulus 1239 MPa higher than that of pure PMMA. The glass transition temperature of the PMMA/n-Z also increased, i.e., from 73°C for the pure PMMA to 86°C for the composite with 5 wt% n-Z addition. [ABSTRACT FROM AUTHOR]

In this work, the magnetic carbon sand (MCS) have been successfully prepared by the chemical vapor deposition (CVD) on sands using adamantane (C10H16) as a precursor. The MCS was obtained by the deposition of adamantane precursor on sand at 1050 °C. The magnetization of MCS has been measured by the vibrating sample magnetometer (VSM) with applied magnetic field in the range between -15 and 15 kOe. From VSM results, the magnetic hysteresis loop is observed in MCSs indicating the ferromagnetic behavior without the presence of magnetic elements. The saturated magnetization has been observed as high as 72 m-emu/g at room temperature. From the Raman-spectroscopy measurement, the observed ferromagnetism in MCS may come from the unpaired electrons in carbon (i.e. dangling bond) resulted by calcining adamantane at high temperature. This finding suggests an inexpensive method for preparing magnetic particles which can be applied in broad applications such as bio-compatible drug delivery and large-scale magnetic shielding. [ABSTRACT FROM AUTHOR]

A series of six shots were performed using a graded areal density quasi-isentropic loading (ramp wave) generation technique, this is in order to develop and validate a non-metallic materials capability which is compatible with the magnetic particle velocity gauge technique. Building upon previous work using rapid prototyped alumina flyers, this trial used machined sapphire components which offered superior material quality. The aim of this series was to observe the loading generated in a target using Het-V diagnostics at multiple spatial locations in order to determine the uniformity of the loading, and then to compare the results with Autodyn modelling. Six shots were fired on a single stage gas gun using several system variations at a velocity range of 200 to 700 ms−1. The ramp loading in a lithium fluoride (LiF) target was found to be approximately uniform in all cases using Het-V probes spaced over a ∼17 mm square central region. Comparison with 3-D Autodyn modelling was reasonable at the higher end of the impact velocities, but poor at the lower end. This is attributed to issues with the Johnson Holmquist sapphire strength/failure model parameters used which were not independently validated. Further experimental and modelling work would be of interest in order to inform a predictive design capability for the loadings generated by the system. [ABSTRACT FROM AUTHOR]

This report examines a series of 5 plate-impact experiments on the HMX-based explosive PBX 9404 (94%wt HMX, 3%wt CEF, 2.9%wt NC, 0.1%wt DPA), Lot 10102Y. These experiments were performed using single- and 2-stage gas guns at Los Alamos National Laboratory, and cover a pressure range of 3–6.7 GPa. Through the use of an embedded magnetic particle velocity gauge technique, in situ particle velocity histories and shock wave times of arrival (ToA) are obtained at 11 gauge locations and 116 'shock tracker' points, respectively. Analysis yielded measurements of the reactant Hugoniot in the shock velocity-particle velocity plane, and run distances to detonation as a function of initial pressure. The shock Hugoniot was found to agree with the work of Ramsey and Popolato (4th Detonation Symposium) but differ from a legacy Hugoniot published in "LASL Explosive Property Data". Run to detonation data agree within error, but with a small systematic shift. This shift may be at least partially attributed to the legacy analysis techniques used in in the older data set. Hugoniot and Pop pot fits for this lot of PBX 9404 are reported, and detailed particle velocity and ToA data are available for use by the modeling community in the LANL Small Scale Database. [ABSTRACT FROM AUTHOR]

A comparative study of structure, stability and magnetic properties of Ni nanoparticles (NPs) synthesized by NaBH4 reduction method (SBR) and Polyol process (PP) has been carried out. Temperature and field dependence magnetization measurements suggest that 600 °C air annealed for 1 hour samples exhibit weak and strong magnetic properties for samples prepared by PP and SBR methods respectively. From the structural and magnetic measurements we conclude that Ni particles prepared by SBR and annealed at 600 °C air develops in to core-shell structure NPs while PP NPs under similar conditions show heterogeneous magnetic (Ni/NiO) behavior. [ABSTRACT FROM AUTHOR]

The nanocrystalline cobalt ferrite (CoFe2O4) was successfully synthesized by dextrose assisted sol-gel auto combustion method. The structural, morphological and magnetic properties of prepared sample were studied using standard technique. Pure phase formation of cobalt ferrite without additional impurity was observed in X-ray diffraction pattern. The average crystallite size (t = 20.6 nm), lattice parameter (a = 8.38 Å) and other structural parameters were calculated from XRD data. The SEM image shows good homogeneity and sponge like morphology of the prepared sample with average grain size of 69.8 nm. The presence of the peak around 608 cm−1 and 415 cm−1 in IR spectrum confirmed that the formed product is spinel ferrite. The values of saturation magnetization (Ms) and remanent magnetization (Mr) were obtained from M-H curve and found to be 74.5 emu/gm and 44.1 emu/gm respectively. Thus, it is observed from experimental results that dextrose can be used as a fuel for synthesis of cobalt ferrite nanoparticles with smaller size particles and improved magnetic properties for various technological applications. [ABSTRACT FROM AUTHOR]

CoFe2O4/SiO2 magnetic nanoparticles have been prepared by co-precipitation methods. The structure, morphology and magnetic properties were analyzed using various characterization such as XRD, FTIR, TEM, and VSM respectively. The surface was modified using silica in order to create new active sites as a potential adsorbent to remove Ni and Cu ions from wastewater. The result obtained that the crystal size of CoFe2O4/SiO2 increased compared to uncoated magnetic nanoparticles. The size of crystal before and after coated using silica was found about 8 nm and 11 nm, respectively. The FTIR results suggested that stretching vibration of Fe/Co-O occurs at a wavenumber of 470.63 cm−1 and 399.47 cm-1, and wavenumber of 1033.85cm-1 indicate bending vibration of Si-O-H. It confirmed that SiO2 was successfully coated the nanoparticles. The magnetic properties of coated material were found decreased after the silica addition is about 22.34 emu/g, while the magnetic saturation (Ms) of uncoated cobalt ferrite is about 37.56 emu/g. The decrease of the value is due to the presence of silica properties as non-magnetic materials and the presence of impurity (α-Fe3O4) on the core material. In the adsorption process, the other factors were also observed (e.g. the effect of particles size and magnetic properties). The adsorption capacity of silica-coated CoFe2O4 reaches about 77.48 mg/g and 74.46 mg/g for Ni and Cu ions, respectively. The smallest particles size has a wide surface area and the highest magnetic saturation gives the greatest influence on the adsorption capacity of Ni and Cu ions. The results confirm that the silica-coated CoFe2O4 magnetic nanoparticles could be a potential adsorbent for the effective removal of heavy metals from aqueous solutions. [ABSTRACT FROM AUTHOR]

The composite of hybrid magnet consists of a combination of NdFeB magnetic particles with SrFe12O19 (Sr-ferrite) and uses epoxy resin as binder. This study was done to analyse the physical, mechanical (compressive strength) and magnetic properties of composite of hybrid magnets. The composition ratio Sr-ferrite–NdFeB in weight % was varied into several values: 90% : 10%, 80% : 20%, 70% : 30% and 60% : 40%, while the epoxy resin composition was 3% of total mass of magnetic particles. The process of forming pellet samples were done by cold compression using a 10 tonf force. Sample hybrid composite magnet systems Sr-ferrite–NdFeB with 30% and 40% NdFeB contents have the highest density (5.65–6.02 g/cm3) and magnetic flux (710–820 gauss). The composition ratio Sr-ferrite–NdFeB strongly affects the bulk density and magnetic flux, but it gives small influence on shore hardness, remanence, and coercivity. [ABSTRACT FROM AUTHOR]

In this research, acrylic acid based hydrogels were prepared and impregnated with magnetic nanoparticles to enhance the efficiency of the adsorption and desorption of heavy metals. Acrylic acid and itaconic acid both are short chain and possess -COOH group, therefore, they are easily copolymerized and hydrophilic in nature. The acrylic based hydrogel acts as a support to hold the magnetic nanoparticles. Hydrogels were synthesized by using acrylic acid and itaconic acid as monomers at different monomer ratios. The magnetic particles were incorporated through in situ precipitation method by immersing into 0.25 M Fe (II) and 0.5 M Fe (III) ion aqueous solutions in the molar ratio of 1:2 for metal ions loading. The swelling behaviour of the plain acylic acid hydrogel and plain acrylic acid-co-itaconic acid hydrogel that were soaked in two different water solutions such as sea water and distilled water were studied. Result shows that plain acrylic acid-coitaconic acid hydrogel has the tendency to swell more than plain acrylic acid hydrogel. The absorption and desorption capacity of the materials were tested in 0.1 M of cobalt and lead solutions. The materials show promising results and can be used to remove pollutants from industrial effluent. [ABSTRACT FROM AUTHOR]

A rubber composite magnet was made by using magnetic particle of Sr-ferrite (SrFe12O19) and silicon rubber (SR) as a binder with composition 10%, 20 %, 30%, and 40 % wt. of SR, both raw materials are mixed until homogen and then formed by casting method. Furthermore the samples which have been formed in sheet form were dried at room temperature for 6 hours. Characterization of samples was carried out which included tensile strength testing, hardness and magnetic properties using VSM. The characterization result shows that the value of tensile strength (UTS) tends to increase with increasing of SR content, but the elongation value tends decrease with increasing of SR content. It means that the samples with high content of SR become soft and flexible, maximum value of UTS and elongatiaon are 7.08 MPA and 178 % respectively. The result of hardness measurement shows that the sample rubber magnet composite has a shore hardness value of around 23-38 HA.The highest value of each magnetic property is achieved in a sample with 10% SR which has a remanence value of 56 emu / g and a coercivity value of around 1900 Oe. [ABSTRACT FROM AUTHOR]

In this work, we prepared magnetic nano particles in format (CoxZn1-x Fe2 O4). The method used is microwaveassisted combustion with type of fuel, glycine. This method is characterized via the rapid acquisition in nanoparticles with a boundary of (30-12 nanometers) in 20 minutes. Structure and magnetic properties were tested using XRD, FESEM, FTIR, and finally the Vibrating Sample Magnetometer (VSM), which revealed the presence of Super para magnetic samples. The x-ray spectrum shows that the pattern of the particles formed is of the face -centered cubic and the theoretical values of the lattice constant and crystal density (dx) and crystalline size (D) are calculated. The FTIR spectrum shows two absorption bands ranging between 400 and 600 cm-1. These bands indicate that the composition of the spectrum for all the samples is ferrite. [ABSTRACT FROM AUTHOR]

It has been shown that high activity at interaction of particles of finely divided powders of ferromagnetic materials leading to development of aggregates and increase of internal friction hampers the production of high-quality powder parts. A special technology has been offered as an effective solution of this problem, which is based on the application of a variable magnetic field under the influence of which weighing of particles and setting them in intensive magneto-vibrational motion and destruction is provided. A design model of magneto-vibrational destruction of aggregates has been developed which establishes the dependence of the destruction degree of aggregates of finely divided powders of hard-magnetic materials under the conditions of their magneto-vibrational interaction from induction and a gradient of a variable magnetic field induction. This article presents the results of pilot studies of the impact of induction and a gradient of a variable magnetic field induction on destruction degree of aggregates of finely divided powders under the conditions of their magneto-vibrational interaction with the application of a method of sieve classification in the highgradient electromagnetic field. It has been established that the increase of induction of a direct component of magnetic field leads to the increase in aggregate resistance to external factors; and its destruction is effective only at small values of induction of a magnetic field. Besides, the increase of productivity of a magneto-vibrational technology for account of reduction of production time of one magnet in comparison with a wet-mud technology has been noted. [ABSTRACT FROM AUTHOR]

The BGO-OD experiment at the ELSA accelerator facility uses an energy tagged bremstrahlung photon beam to investigate the internal structure of the nucleon. The setup consists of a highly segmented BGO calorimeter surrounding the target, with a particle tracking magnetic spectrometer at forward angles. BGO-OD is ideal for investigating low momentum transfer processes due to the acceptance and high momentum resolution at forward angles. This enables the investigation of strangeness photoproduction where t-channel exchange mechanisms play a dominant role. A detailed understanding of this low-momentum transfer region is also crucial for constraints in hypernuclei electroproduction, and sensitive to any extended, molecular-like interactions that may contribute to reaction mechanisms. Progress in the study of K+Λ(1405) differential cross sections and line shapes, K0 photoproduction, and differential cross section measurements for K+Λ and K+Σ0 photoproduction at extremely forward angles is presented. Opportunities for hypernuclei studies are also discussed. [ABSTRACT FROM AUTHOR]

In the present study, the investigations on an ultra thin wedge thin film prepared by Ion Beam Sputtering (IBS) technique are presented. This film consists of a Co ultra thin wedge layer (thickness ranging from 0.5nm-4nm)sandwiched between a pair of Au layers. The thickness dependent structural and magnetic properties measured are reported. Three different locations, the lowest, middle and the highest thickness were probed for the present work. The X-ray reflectivity measurements reveal roughness induced intermixing of Co and Au layers. However, no signature of alloy formation is observed. X-ray diffraction measurements show polycrystalline nature of film. The hysteresis loops are not properly seen on lowest thickness side of film due to very less number of magnetic Co particles, but when the thickness is high enough show the ferromagnetic character then clear ferromagnetic hysteresis loop is observed and the coercivity is seen to increase with increase in Co layer thickness. The overall results are interpreted in terms of growth of Co particles in between adjacent Au layers. [ABSTRACT FROM AUTHOR]

A series of MnxZn1–xFe2O4 (x = 0.5, 0.6, 0.7) nanoferrites have been produced by sol-gel auto combustion method in order to study their structural and magnetic properties. XRD patterns revealed the formation of ferrite phase along with the co-existence of secondary phases. Themodynamical stability of Mn2+ in the spinel structure improved the formation of ferrite phase with the substitution of Mn2+. The saturation magnetization is increased with the increase in Mn2+ ion concentration. Cation redistribution between tetrahedral and octahedral sites seems to be more predominant in the present ferrite systems which are affecting the magnetic properties of the ferrite systems. In the present manuscript the results of structural and magnetic studies are reported. [ABSTRACT FROM AUTHOR]