Serial numbers are marks present on several day-to-day objects, created by manufacturers for purposes such as quality control, product tracking and to prevent counterfeiting. In the case of firearms, these characters can be obliterated or damaged by natural processes or intentionally by criminals to prevent positive identification of stolen property. One non-destructive method employed by crime laboratories for the restoration of obliterated characters is the magnetic particle method. The present work aims to study the synthesis and application of waste-made magnetic nanoparticles in the recovery of adulterated markings. A set of analytical-grade materials and metallic waste magnetic nanoparticles were synthesized for comparison purposes. Chemical characterization tests by X-ray fluorescence, morphological tests by scanning electron microscopy (SEM), and magnetization tests by vibrating sample magnetometer (VSM) were performed. The efficacy of the synthesized nanoparticles was tested on 1020 steel plates previously engraved and adulterated by sanding. Both homemade magnetic nanoparticles demonstrated superior performance compared to commercial magnetic particles. The application of homemade magnetic particles, especially using waste as the source of production, decreases the cost of the material and is environmentally friendly. The development of this material makes magnetic serial number restoration a better option for widespread use in forensic procedures. daytoday day objects control counterfeiting firearms property nondestructive non destructive wastemade made markings analyticalgrade analytical grade Xray X ray fluorescence SEM, SEM , (SEM) VSM (VSM performed 102 sanding particles production friendly procedures (SEM 10 1

This work aims to synthesize the alloy Co64Nb30B6 through mechanical alloying using a planetary ball mill. A disc rotation per minute and a ball/powder weight ratio of 300 rpm and 10:1 were used, with a milled time of 10 h, respectively. The characterization of the Co64Nb30B6 alloy was performed by X-ray diffraction (XRD), examined by scanning electron microscope-energy dispersive X-ray spectroscopy (SEM-EDS), thermoanalytical techniques (TGA/DTA), vibrating sample magnetometer (VSM) and confirmed by Braunauer, Emmet e Teller (BET) method type IV isotherms with a hysteresis loop for mesoporous materials. The results indicated that the evolution of the amorphous phase in the Co64Nb30B6 composition through the mechanical alloying process exhibited good soft magnetic properties with the addition of the metalloid element B and its excellent unique ferromagnetic properties. Through thermoanalytical analysis (TGA/DTA), it was shown that at higher temperatures, Co and Nb ions are oxidized by the environment and, therefore, the mass can be slightly increased to 14.9% and a probable contribution of boron in evolution stability thermal and magnetic in the amorphous phase, respectively. This suggests that the newly developed high-performance amorphous alloy Co64Nb30B6 has great application potential. CoNbB Co64Nb30B mill ballpowder powder 30 101 1 10: used h respectively Xray X ray XRD, XRD , (XRD) microscopeenergy microscope energy SEMEDS, SEMEDS SEM EDS (SEM-EDS) TGA/DTA, TGADTA TGA/DTA TGA DTA (TGA/DTA) VSM (VSM Braunauer BET (BET materials temperatures therefore 149 14 9 14.9 highperformance high performance potential 3 (XRD (SEM-EDS (TGA/DTA 14.

Lipases have been used in industrial processes as biocatalysts for transesterification reactions. The synergism between enzymes and magnetic properties may be reached by using magnetic nanoparticles (MNPs) as support to immobilize them in aggregate structures, denominated by magnetic crosslinked enzyme aggregates (MCLEA). One of the advantages of such supports is the possibility of using magnetic separation for enzyme recovery, reducing costs and allowing reuse in continuous systems. Here, porcine pancreatic lipase (PPL) was immobilized onto functionalized magnetite support (Fe3O4-APTS) with a protein binding efficiency of 78.84%. Physical and chemical properties of the nanoparticles and immobilized lipase were characterized by X-ray diffraction (XDR), transmission electron microscopy (TEM), infrared spectroscopy (FTIR), dynamic light scattering (DLS), zeta potential, vibrating sample magnetometer measurements (VSM), and 57Fe Mössbauer spectroscopy. The immobilized lipase additionally exhibited improved stability across wide pH and temperature ranges compared with free lipase. The immobilized derivate also attained good reusability, maintaining 61.37% of its initial activity after 6 reaction cycles. Through magnetic behavior and also because of its surface modification to crosslinking the enzyme, the MCLEA produced in this work has enhanced the biocatalytic activities of PPL. reactions MNPs (MNPs structures MCLEA. . (MCLEA) recovery systems Here PPL (PPL Fe3O4APTS FeOAPTS Fe3O4 APTS Fe O (Fe3O4-APTS 7884 78 84 78.84% Xray X ray XDR, XDR , (XDR) TEM, TEM (TEM) FTIR, FTIR (FTIR) DLS, DLS (DLS) potential VSM, VSM (VSM) reusability 6137 61 37 61.37 cycles (MCLEA FeO Fe3O 788 7 8 78.84 (XDR (TEM (FTIR (DLS (VSM 613 3 61.3 78.8 61. 78.

This work describes the route to prepare a novel core-shell catalyst based on 1,4-diazabicyclo[2,2,2]octane (DABCO) supported magnetic nanoparticles (MNPs). The morphology and composition of the obtained catalysts were characterized by Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), X-ray powder diffraction (XRD), transmission electron microscopy (TEM), quantum design vibrating sample magnetometer (VSM) and scanning electron microscopy (SEM). These nanomaterials presented high performance as a basic catalyst for Knoevenagel condensation between malononitrile and aldehydes, leading to products with excellent yields (84-99%) and short reaction times (5-60 min). Furthermore, it was also efficient in the condensation of isatins with 4-phenylthiosemicarbazide, resulting in isatin-β-thiosemicarbazones with high yields (81-94%) and short times (60-180 min). It is worth mentioning that the catalyst was recovered and reused in these two kinds of reactions after six cycles without significant yield loss. coreshell core shell 1,4diazabicyclo2,2,2octane 14diazabicyclo222octane diazabicyclooctane 1,4 diazabicyclo 2,2,2 octane 1 4 2 DABCO (DABCO MNPs. MNPs . (MNPs) Fouriertransform Fourier transform FTIR (FTIR spectroscopy TGA, TGA , (TGA) Xray X ray XRD, XRD (XRD) TEM, TEM (TEM) VSM (VSM SEM. SEM (SEM) aldehydes 8499% 8499 84 99% 99 (84-99% 560 5 60 (5-6 min. min min) Furthermore 4phenylthiosemicarbazide, 4phenylthiosemicarbazide phenylthiosemicarbazide phenylthiosemicarbazide, 4-phenylthiosemicarbazide isatinβthiosemicarbazones isatin β thiosemicarbazones 8194% 8194 81 94% 94 (81-94% 60180 180 (60-18 loss 4diazabicyclo2 2octane 14 1, 222 2,2, (MNPs (TGA (XRD (TEM (SEM 849 8 9 (84-99 56 6 (5- 819 (81-94 6018 18 (60-1 4diazabicyclo 22 2,2 (84-9 (5 (81-9 601 (60- 2, (84- ( (81- (60 (84 (81 (6 (8

In this study, the preparation and adsorption properties of cobalt ferrite core-shell nanoparticles coated with silica and decorated with poly(4-vinylpyridine) (CoFe2O4@SiO2-P4VP) applied to bisphenol A (BPA) adsorption were described. The CoFe2O4-based core was coated by a nanometric layer of silica under Stöber conditions and followed by coating with poly(4-vinylpyridine) via surface polymerization in miniemulsion. The characterizations involved transmission electron microscopy (TEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), Fourier transform infrared (FTIR), thermogravimetry (TGA), dynamic light scattering (DLS) and zeta potential. The polymeric core-shell nanoparticle showed a spherical structure with a magnetic core of ca. 11 nm and a layer of silica of ca. 4 nm. The amount of poly(4 vinylpyridine) that decorated the nanoparticle surface was verified by thermogravimetric analysis. CoFe2O4@SiO2-P4VP exhibited the capacity to adsorb bisphenol A. The chemometric model indicated a significant effect between the ionic strength and pH of the solution in the adsorption of bisphenol A. CoFe2O4@SiO2-P4VP presented a superior adsorption capacity towards BPA (46.6 mg g-1) in optimized conditions. The adsorption kinetics of BPA by CoFe2O4@SiO2-P4VP involved a pseudo-second order process. Also, the adsorption isotherm indicated a multilayer process with data well-adjusted by Freundlich equation. The nanomaterial CoFe2O4@SiO2-P4VP can be reused in adsorption of BPA for up to eight cycles. study coreshell shell poly4vinylpyridine polyvinylpyridine poly vinylpyridine poly(4-vinylpyridine CoFe2O4@SiO2P4VP CoFe2O4SiO2P4VP CoFeOSiOPVP CoFe2O4@SiO2 P4VP CoFe2O4 SiO2 CoFe O SiO P VP (CoFe2O4@SiO2-P4VP (BPA described CoFe2O4based CoFeObased based miniemulsion TEM, TEM , (TEM) Xray X ray XRD, XRD (XRD) VSM, VSM (VSM) FTIR, FTIR (FTIR) TGA, TGA (TGA) DLS (DLS potential ca 1 poly4 poly( analysis 46.6 466 46 6 (46. g1 g g-1 pseudosecond pseudo second Also welladjusted well adjusted equation cycles SiO2P4VP CoFe2O4SiO2 CoFeOSiO CoFe2O4@SiO PVP CoFeO CoFe2O (TEM (XRD (VSM (FTIR (TGA 46. (46 g- SiOPVP CoFe2O4SiO (4 (

BACKGROUND: Sentinel lymph node biopsy (SLNB) is performed for staging and prognostication of breast cancer (BC) in cases with a clinically and radiologically negative axilla. Using blue dye and a radioactive colloid injection is considered the gold standard for SLNB. This study aims to evaluate the SLNB outcomes before and after the introduction of Sentimag at an academic breast unit. Sentimag uses an injection of superparamagnetic iron oxide which is then detected in the sentinal lymph node using a magnetometer METHOD: A retrospective cohort study was performed comparing SLNBs done from 1 January 2017 to 31 December 2018. During 2017, a nuclear medicine technique was used for all SLNBs, while the Sentimag system was used in 2018 RESULTS: There was no difference between the two groups comparing age, T-stage, size of tumour, and molecular status. The only statistically significant difference found was more higher-grade tumours in the group where a nuclear medicine technique was used in 2017 (p = 0.04). There was no difference in the type of surgery performed comparing mastectomy and breast-conserving surgery rates between the two groups. There was an 11% increase in the number of patients who had an SLNB done with the Sentimag technique (2018). In 2017, 42% (58/139) had an SLNB and in 2018, 53% (59/112) had an SLNB CONCLUSION: This result demonstrates the feasibility of the magnetic technique for SLNB in a resource-limited setting. This new method shows promise as a safe and effective technique for SLNB - it is a valuable alternative in the absence of nuclear medicine (N.Med) facilities

Abstract We report on the magnetization of core-shells nanoparticles. Magnetic nanoparticles (MNPs) with a core of magnetite of 13 nm diameter covered with a shell of dopamine (1.1 nm thickness) are studied through vibrating sample magnetometer (VSM), Monte Carlo (MC) computer simulations, and using an analytical model. All parameters involved in the theoretical analysis are experimentally determined, namely, the magnetic moment, temperature, magnetic field, core diameter, shell thickness, magnetic anisotropy, and particle concentration. The dependence of the magnetization with the magnetic field obtained through VSM and MC shows a 1% discrepancy in the magnetic saturation and up to 40% in the initial magnetic susceptibility. However, the dependence of the magnetization with the temperature obtained by MC indicates that the MNPs obey the Curie law above a critical temperature of 100 K. Furthermore, our findings indicate that the dipolar interactions play an important role on the magnetization in the interval 20 < T < 100 K. That critical temperature domain is very close to the blocking temperature measured following the zero-field-cooled and zero-cooled protocols, where the dipolar interactions between MNPs become significant. Further analysis shows a Langevin-like behavior for both experimental and theoretical magnetizations.

Abstract In this work, neodymium (Nd3+) doped strontium hexaferrite was obtained using the sol-gel based Pechini method. The cation distribution was modified by doping with different amounts of Nd3+ ions when 0.0 ≤ x ≤ 0.4 according to the chemical expression Sr1-xNdxFe12O19 the powders were sintered at 1100 °C for 1 h. The influence of the neodymium was analyzed, and the magnetic and structural properties have been associated with the fabrication method. The crystalline phases, structure, and particle morphology of the samples were determined by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. In addition, the magnetic properties were measured at room temperature using a vibrating sample magnetometer with an applied field of up to 20 kOe. Moreover, magnetization and coercivity values are influenced by the neodymium content. The results showed that the Pechini sol-gel method allows a limited solubility of the Nd3+ ions on the hexaferrite structure.

Abstract Aflatoxin B1 (AFB1) is a highly toxic mycotoxin that enters the human body through the food chain and poses a serious threat to human health. In this paper, polydopamine (PDA)-coated Fe3O4 magnetic nanoparticles (Fe3O4@PDA MNPs) were prepared by the co-precipitation method to enrich aflatoxin from edible oil. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and vibrating sample magnetometer were used to characterize the Fe3O4@PDA MNPs. Using the obtained Fe3O4@PDA MNPs as an adsorbent, a simple method for enriching AFB1 from samples by magnetic solid phase extraction (MSPE) combined with fluorescence rapid detection was developed. The effects of the ratio of Fe3O4 MNPs to PDA, adsorption dosage, sample volume, adsorption time, and elution time on enrichment of AFB1 were investigated to determine the optimal experimental conditions. This method has good intraday and daytime precision.

Resumen Este artículo reporta la síntesis y caracterización de Bi1-xLuxFeO3 (x = 0.00, 0.02 and 0.04) producido por reacción de estado sólido, con el fin de evaluar la influencia del catión lutecio sobre las propiedades estructurales y magnéticas de la ferrita de bismuto (BiFeO3). Las muestras fueron caracterizadas por difracción de rayos X (DRX), microscopia electrónica de barrido (MEB), espectroscopia de energía dispersiva de rayos X (EDX) y análisis magnético por medio de magnetometría de muestra vibrante (VSM) en un rango de temperatura de 50 a 320 K. Los resultados obtenidos permitieron confirman la formación de materiales cristalinos de estructura romboédrica, grupo espacial R3c (161), de morfología definida y tamaños de partícula entre 2.25 y 4.50 μm. La inserción de Lu3+ en la estructura provocó un aumento en la magnetización, la pureza de BiFeO3 y una disminución en la temperatura de síntesis en comparación con lo reportado en la literatura.

Abstract This paper reports the synthesis and characterization of Bi1-xLuxFeO3 (x = 0.00, 0.02, and 0.04) produced by solid-state reaction, in order to evaluate the influence of lutetium on the structural and magnetic properties of bismuth ferrite (BiFeO3). The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and magnetic analysis by vibrating sample magnetometer (VSM) in the temperature range from 50 to 320 K. The obtained results allowed confirming the formation of crystalline materials of rhombohedral structure, space-group R3c (161), defined morphology and particle sizes between 2.25 and 4.50 μm. The Lu3+ insertion in the structure caused an increase in magnetization, purity of BiFeO3, and a decrease in the synthesis temperature as compared with the reported in the literature.

Abstract We prepared 42P2O5-40ZnO-(18-x)Na2O-(x)NiO glasses doped with xNiO where 1 ≤ x ≤ 6 mol.%. The optical absorption indicates that the nickel ions exist in both sites tetrahedral and octahedral as the concentration of NiO is increased. This investigation has provided the increasing degree of disorder in the glass network at higher concentrations of NiO. The magnetic characteristics investigated using two techniques: electron spin resonance spectra and magnetic properties using vibrating sample magnetometer at room temperature. The electron spin resonance spectra exhibit resonance signal without hyperfine interaction of all the investigated glass samples. It is found that Ni2+ ions were in octahedral sites and it has 3A 2g as ground state. The spin-Hamiltonian parameters are evaluated from the electron spin resonance spectra and we found a variation of g || and g ⊥ with different nickel concentration. Interesting results are found for the number of Ni2+ ions participating in resonance (N) and paramagnetic susceptibility (χ). The magnetic properties were performed at room temperature under an applied field of 20 kOe and the hysteresis loops of the powders were extracted for all the considered samples.

In this study, a novel deep eutectic solvent (DES) containing choline chloride and ethylene glycol was synthesized, and the magnetic polydopamine (PDA) was modified with this deep eutectic solvent to form Fe3O4@PDA-DES. Fourier transformed infrared spectroscopy, scanning electron microscopy, and vibrating sample magnetometer were used to characterize the proposed adsorbent. Then, this magnetic material was used as an adsorbent in the magnetic solid phase extraction process for the extraction of four sulfonylurea herbicides in water samples. The main parameters relevant to this method were investigated. Under the optimum conditions, the linearity was obtained by five points in the concentration range of 1.0-200 µg L-1 and with the correlation coefficients (r) ≥ 0.9927. The enrichment factors were in a range of 495 to 615 and the relative standard deviations were less than 4.3%. The limits of detection varied from 0.0092 to 0.0113 µg L-1. The recoveries of environmental water samples were 61.9 to 100.1%, and the recoveries of drinking water samples were 71.1-101.9%. All results highlighted the excellent potential of magnetic solid phase extraction coupled with ultra-high performance liquid chromatography strategy in selective separation and extraction of sulfonylurea herbicides in water samples.

ABSTRACT In this study, cobalt ferrite nanomaterial with inverse spinel structure was synthesized via a co-precipitation method using Co(NO3)3.6H2O and Fe(NO3)3.9H2O. A 15% NH4OH solution was used as an alkaline agent for pH adjustment. Oleic acid was used as a coating agent on the surface of the synthesized cobalt ferrite nanoparticles. PXRD analysis confirmed that the obtained material had a main CoFe2O4 cubic crystal structure with space group Fd-3m and lattice parameters a=b=c= 8.40 Å (JCPDS standard card no = 01-077-0426). According to the SEM analysis, the pseudo-spherical particles size distribution and morphology of the as-synthesized nanomaterial were homogeneous. The magnetic behavior of the obtained material was analyzed by vibrating-sample magnetometer (VSM). Besides, anti-cancer effect of the as-synthesized cobalt ferrite nanoparticles was examined on an experimental model of acute myeloid leukemia (CML) K562 cell line for the first time. Inhibition of cell growth and cytotoxicity (apoptosis) that are characteristics features of cobalt ferrite nanoparticles are tested on K562 cell line. The results showed growth and viability inhibition and induction of apoptosis in K562 cells treated with the nanoparticles.

Resumo Nanopartículas de ferrita de cobalto dopada com Y3+, CoYxFe2-xO4 (x=0,00, 0,05, 0,10, 0,15), foram sintetizadas usando a técnica de autocombustão sol-gel. A estrutura de espinélio cúbico monofásica foi confirmada pela técnica de difração de raios X. O parâmetro da rede aumentou com o aumento do teor de Y3+ na ferrita de cobalto e variou de 8,3876 para 8,4271 Å. Imagens de MEV mostraram que as amostras possuíram nanopartículas cristalinas distintas de forma esférica com pequena aglomeração. Os resultados de EDAX mostraram boa concordância com a composição especificada. A medição magnética usando o magnetômetro de amostra vibrante (VSM) registrou uma redução na magnetização de saturação (Ms) e coercividade (Hc) pela substituição de Y3+. Os valores de Ms e Hc variaram de 66,61 a 17,52 emu/g e 1168,9 a 801,9 Oe, respectivamente. As propriedades elétricas da ferrita de cobalto substituído com Y3+ foram estudadas por meio da medição de constante e perda dielétrica. Com o aumento da frequência o valor da constante dielétrica diminuiu, conforme comportamento natural da ferrita.

Abstract Y3+-doped cobalt ferrite nanoparticles, CoYxFe2-xO4 (x=0.00, 0.05, 0.10, 0.15), were synthesized using the sol-gel auto-combustion technique. Single-phase cubic spinel structure was confirmed by the X-ray diffraction technique. The lattice parameter increased with the increase of Y3+ content in the cobalt ferrite and varied from 8.3876 to 8.4271 Å. FE-SEM images showed that the samples had distinct crystalline nanoparticles of spherical shape with small agglomeration. EDAX results showed good agreement with the particularized composition. Magnetic measurement using a vibrating sample magnetometer (VSM) recorded a reduction in saturation magnetization (Ms) and coercivity (Hc) by Y3+ substitution. The values of Ms and Hc ranged from 66.61 to 17.52 emu/g and 1168.9 to 801.9 Oe, respectively. The electrical properties of Y3+-substituted cobalt ferrite were studied by measuring the dielectric constant and loss. With increasing frequency, the value of the dielectric constant decreased, as a natural behavior of the ferrite material.

Abstract: The technique proposed in this research demonstrates a real time nonlinear data fusion solution based on extremely low-cost and grade inertial sensors for land vehicle navigation. Here, the utilized nonlinear multi-sensor data fusion (MSDF) is based on the combination between extremely low-cost micro electrical mechanical systems (MEMS) inertial, heading, pressure, and speed sensors in addition to satellite-based navigation system. The integrated navigation system fuses position and velocity states from the Global Positioning System (GPS), the velocity measurements from an odometer, heading angle observation from a magnetometer and navigation states from an inertial navigation system (INS). The implemented system performance is assessed through the post-processing of collected raw measurements and real time experimental work. The system that runs the real-time experiments is established on three connected platforms, two of them are based on a 32-bit ARMTM core and the third one is based 16-bit AVR ATMEL microcontroller. This microcontroller is connected to an on-board diagnostics (OBD) shield to collect the vehicle speed measurements. The raw data obtained from the integrated sensors is saved and post processed in MATLAB®. In normal conditions, the estimated position errors are reduced through the usage of INS/GPS integration with heading observation angle from a magnetometer. In GPS-denied environments, the integrated system uses the observations from INS, magnetometer in addition to the velocity from odometer to ensure a continuous and accurate navigation solution. A complementary filter (CF) is implemented to estimate and improve the pitch and roll angles calculations. In addition to that, an unscented Kalman filter (UKF) is used cascaded with the designed CF to complete the designed sensors fusion algorithm. Experimental results show that the designed MSDF can achieve a good level of accuracy and a continuous localization solution of a land vehicle in different GPS availability cases and can be implemented on the available in the market processors to be run in real time.