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With the development of switching power supplies, miniaturization and high efficiency become hot research issues, and decreasing high-frequency losses is an effective method to achieve it. In this article, the effect of different calcination temperature on the power losses of MnZn ferrites at high frequency (500 kHz) over a broad temperature range is reported. The MnZn ferrites samples were prepared by ceramic process and the effect of calcination temperature was analyzed. The raw materials were calcined at 775 ℃, 800 ℃, 825 ℃, 850 ℃, 875℃, 900 ℃, 925 ℃ and 950 ℃, and the regular fluctuations of particle size (as-calcined), density (as-sintered) and magnetic properties are presented in this work. It is shown that the samples calcined at 850 ℃ exhibit optimal microstructure and magnetic properties. The newly developed MnZn ferrites are characterized by sintered density of 4.61 g/cm³, initial permeability of 1223 (10 kHz/0.1 mT/25 ℃), saturation magnetic flux density of 488 mT (10 kHz/1200 A/m/25 ℃) and power losses of 68 mW/cm³ (500 kHz/50 mT/100 ℃).

Mesoporous CoFe2O4 nanowires (NWs) were prepared with ordered mesoporous SBA-15 silica, and then were used to activate peroxymonosulfate (PMS) to degrade ciprofloxacin (CIP). All results showed that mesoporous CoFe2O4 NWs efficiently activated PMS and greatly improved the degradation of CIP in aqueous solution. The influence of PMS and CoFe2O4 on the CIP removal was taken into accounted, which indicated that the dominant sulfate radicals for the CIP degradation. Mesoporous-structure of CoFe2O4 NWs could absorb CIP and PMS in high concentration near CoFe2O4 NWs and promoted this degradation. The 100 ml CIP (20 mg/L) could be completely removal in the optimum conditions with 2 mM PMS and 0.3 g/L S-130, and the CIP removal presented the excellent recyclability with the CIP degradation as high as about 93% after four consecutive cycles. Owing to the high efficiency, excellent magnetic respond and good reusability, mesoporous-structured CoFe2O4 NWs could be regarded as the promising heterogeneous catalysts for PMS to degrade CIP.

The isotropic nanoparticles (NPs) and anisotropic bulk samples of MnBi were prepared from Mn NPs by using zero-field and field-assisted reactive sintering, respectively. The MnBi NPs are irregular in shape with size d

One-dimensional nickel (Ni) microwires were synthesized by the magnetic-field-induced (MFI) microemulsion-hydrothermal method using Ni nanospheres as seeds. The influence of the chemical conditions and magnetic field on the morphology and magnetic properties of Ni microwires were investigated by X-Ray diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometry (VSM). The strength of magnetic field greatly affected the morphology and magnetic properties of Ni microwires. The growth and morphology of Ni microwires depended on the competition between Brownian motion and magnetic dipole moments from magnetic field. The larger nanoparticles with the higher magnetic moments preferred to form one-dimensional Ni microwires and their length increased up to several millimeters with the increasing magnetic field strength, while the average diameter of Ni microwires decreased. Furthermore, the easy magnetization direction of Ni microwires was parallel to the direction of magnetic field and the Ni microwires axis.

The effect second milling time on the electromagnetic properties of MnZn ferrites has been studied up to MHz range. The average particle sizes of powder ranging from 1.49 to 1.16 μm were obtained by varying the second milling time from 72 to 324min. It is found that the total losses (Pcv) deteriorate when the second milling time over 252 min and the limit particle size is 1.21 μm. The value of initial permeability (μi) reduces by 20% when the particle size is 1.16 μm due to the uneven distribution of grain size, indicating that uniform microstructure demands suitable particle size. Meanwhile, the eddy current loss (Pe) and residual loss (Pr) dominate the total loss at 3 MHz playing a significant role in total losses. The hysteresis loss (Ph) and eddy current loss (Pe) deteriorate gradually at 3 MHz when the particle size is 1.21 μm at 100 °C. The residual loss increases greatly with the particle size decreasing at 3 MHz. An excellent MnZn power ferrite possessing high initial permeability (μi = 887), high saturation magnetic flux density (Bs = 531 mT) and low total losses (Pcv = 1940 kW/m3) at 3 MHz-50 mT is synthesized in this research.

Mesoporous indium (In)-doped hematite (α-Fe 2 O 3 ) nanowires were synthesized with mesoporous SBA-15 silica as a hard template, and then the influence of In dopant on the microstructure and gas-sensing performance was investigated in detail. With characterization by transmission electron microscopy, X-ray diffraction, UV–vis spectroscopy, and nitrogen physisorption experiments, it was shown that the average grain size increased for up to 1 mol% In dopant and then decreased with increasing In dopant content, while the surface area changed in the inverse manner. Because of the low melting point of In, In acted as a fluxing agent and entered the α-Fe 2 O 3 lattice when the In content was low, and the average grain size increased. With higher In content, In precipitated out the lattice and existed at the grain boundary, and the grain size decreased. It is concluded that In in the lattice increased lattice distortion and In at the boundary increased the surface area and oxygen vacancies, which were both beneficial for improving the gas-sensing performance. The response of In-doped α-Fe 2 O 3 nanowires increased by about 30%–50% as compared with that of pure α-Fe 2 O 3 nanowires. The gas sensor based on 3 mol% In–doped α-Fe 2 O 3 nanowires exhibited the best gas response and a rapid response-recovery time toward ethanol at the optimum temperature. Owing to the same valence, In dopant affected only the microstructure and components of the α-Fe 2 O 3 lattice, which was necessary to improve the gas-sensing behavior.

High surface area nickel oxide nanowires (NiO NWs), Fe-doped NiO NWs andα-Fe2O3/Fe-doped NiO NWs were synthesized with nanocasting pathway, and then the morphology, microstructure and components of all samples were characterized with XRD, TEM, EDS, UV-vis spectra and nitrogen adsorption-desorption isotherms. Owing to the uniform mesoporous template, all samples with the same diameter exhibit the similar mesoporous-structures. The loadedα-Fe2O3nanoparticles should exist in mesoporous channels between Fe-doped NiO NWs to form heterogeneous contact at the interface of n-typeα-Fe2O3nanoparticles and p-type NiO NWs. The gas-sensing results indicate that Fe-dopant andα-Fe2O3-loading both improve the gas-sensing performance of NiO NWs sensors.α-Fe2O3/Fe-doped NiO NWs sensors presented the highest response to 100 ppm ethanol gas (55.264) compared with Fe-doped NiO NWs (24.617) and NiO NWs sensors (3.189). The donor Fe-dopant increases the ground state resistance and the absorbed oxygen content in air.α-Fe2O3nanoparticles in electron depletion region result in the increasing resistance in ethanol gas and decreasing resistance in air. In this way,α-Fe2O3/Fe-doped NiO NWs sensor presents the excellent gas-sensing performance due to the formation of heterogeneous contact at the interface.

Mesoporous Co3O4 nanowires were synthesized with the nanocasting method, and then the dispersed Co 3O4 nanowires (Co3O4-DNWs) were separated from the bundled Co3O4 nanowires (Co3O4-BNWs) by the centrifugation technique. From the characterization with TEM, X-ray diffraction, UV–vis spectra and nitrogen adsorption-desorption isotherm, both samples present the same mesoporous-structure, diameter and the similar defects due to the same synthesis conditions. All results indicate that the microstructures and morphology of Co3O4 nanowires greatly affect the toluene gas sensing performance. Owing to the mesoporous-structures with the high surface area, the sensitivities of both samples are higher than others’. Co3O4-DNWs exhibit the higher specific surface area (44.98 m2 g−1) than Co3O4-BNWs, leading to the excellent gas-sensing properties to toluene gas at the optimized operating temperature of 210℃. Moreover, both samples present the excellent stability and selectivity to toluene gas. The gas-sensing mechanism results from the surface oxygen and toluene gas adsorption through comparing the sensitivity of Co3O4-DNWs and Co3O4-BNWs.

Porous perovskite lanthanum ferrites (LaFeO3) powders were synthesized under the different pH value by sol-gel technique and self-propagating combustion method. After the characterization with XRD, SEM, VSM, nitrogen adsorption-desorption isotherm and UV–Vis spectroscopy, the magnetic properties, photocatalytic activity and gas-sensing performance are discussed in detail. All LaFeO3 samples exhibit ferromagnetism for the spin mismatch due to oxygen vacancies. LaFeO3 powders present the good photocatalytic performance to MB and could be easily separated by magnetic separation technique after photocatalysis. Furthermore, the LaFeO3 gas sensors exhibited the considerable sensitivity to ethanol gas. Among all samples, LF-1 (LaFeO3 powders prepared at pH = 1) present the highest removal rate of MB (68%), the largest saturation magnetization (4.57 emu/g) and the best gas response to ethanol. The highest response for LF-1 sensor reaches (263.4) at the optimized operating temperature of 250 °C to 100 ppm ethanol gas, which should be attributed to the higher oxygen vacancies.

The mesoporous α-Fe 2 O 3 nanowires (NWs) were successfully synthesized by changing the calcination temperature from 550 to 750 °C (marked NWs-550, NWs-650 and NWs-750) via using SBA-15 silica as the hard templates with the nanocasting method. The characterization results indicated that the bandgap of the as-prepared samples hardly changed and the high BET surface areas changed a little with the calcination temperature from 550 to 750 °C. Mesoporous α-Fe 2 O 3 NWs had been found to possess the remarkable gas-sensing performance to ethanol gas. The gas-sensing behavior indicated that α-Fe 2 O 3 NWs-650 exhibited the higher response than that of α-Fe 2 O 3 NWs-550 and α-Fe 2 O 3 NWs-750. The calcination-temperature-dependent gas-sensing properties were mainly attributed to the competition of surface defects and body defects by the crystallization temperature. The lower calcination temperature could create more surface defects to improve the gas-sensing response, while the higher temperature would reduce the body defect and make the charge carriers transport easily. As the result, the suitable calcination temperature was desired to optimize the defects of nanostructures to improve the gas sensitivity.

Ultra-high purity CrO 2 was prepared by decomposing CrO 3 in O 2 with gas pressures up to 40 MPa, which were maintained throughout the decomposition process of CrO 3 to prevent the formation of any other phases of chromium oxides. Our method is different from the traditional methods that start from or under ambient pressures. The high oxygen pressure makes the meta-stable CrO 2 stable from the initial stage of preparation. As a result, the purity of the as-prepared CrO 2 is improved, and this has been further proved by the highest magnetization of the samples. The as-prepared CrO 2 particles show very large grains with flat surfaces, octagonal cross-section, and straight edges, owing to the high mobility of Cr ions in CrO 2 at temperatures above its melting point. The lattice parameters of CrO 2 are a = 4.4176 A and c = 2.9144 A. The maximum value of the magnetic entropy change of the high purity CrO 2 particles is ∼2.83 J/kg·K for an applied field of 1.5 T. The preparation of pure CrO 2 is important for studying its intrinsic properties and for applications in spintronic devices.

Multiferroic heterostructures CoPd/0.68Pb(Mg1/3Nb2/3)O3–0.32PbTiO3 (001) (CoPd/PMN–PT) with the thickness of 10 nm were fabricated via magnetron sputtering. The effect of electric field on remanent magnetization, coercivity, and magnetization reversal have been subsequently investigated. A large electric field modulation of magnetism is obtained in strain-mediated CoPd/PMN–PT multiferroic heterostructures. Not only the remanent magnetization but also the magnetic coercivity of CoPd film can be effectively modulated by an electric field. Up to 30.7% of magnetization difference is observed by electric field at the vicinity of the magnetic coercivity. Taking the advantage of the different coercivity controlled by electric field, the magnetization reversal can be assisted by electric field. The magnetization reversal process of the CoPd/PMN–PT heterostructure is dominated by the Kondorsky model. Our results provide great opportunities for electric field-controlled magnetic devices.

High density MnAl–C magnets with enhanced coercivity and remanent magnetization were prepared by high-pressure compaction of the $$\uptau $$ -phase obtained by annealing the as-prepared gas-atomized powders, which are spherical in shape with size in the range of 1–7 $$\upmu $$ m. The as-prepared gas-atomized powders were composed of $$\upvarepsilon $$ - as the major phase and $$\upgamma _{2}$$ - as the minor phase. The massive phase transformation of $$\upvarepsilon \rightarrow \uptau $$ in the gas-atomized powders occurs at 720 K and accomplishes at 806 K, both of which are lower than those of the water-quenched $$\upvarepsilon $$ -MnAl–C alloys with the same composition. An optimized temperature of 760 K, at which the decomposition of metastable $$\uptau $$ -phase was minimized, was selected to prepare the ferromagnetic $$\uptau $$ - from the $$\upvarepsilon $$ -phase. The spherical $$\uptau $$ -phase powders were pressed at room temperature into two dimensional plates that stack along the direction of compaction, forming high density (98.6%) bulk magnets that exhibit larger coercivity and higher remanent magnetization than that of the $$\uptau $$ -phase powders. The grain size of the compacted samples was observed to be in the range of 10–100 nm. The coercivity (0.34 T) of the dense samples is twice as large as that of the $$\uptau $$ -phase powders, owing to the refined grain size and enlarged dislocation density resulting from high-pressure compaction.

Mesoporous bundled NiFe 2 O 4 nanowires were synthesized using mesoporous silica SBA-15 as hard template, and then NiO nanoparticles were implanted into NiFe 2 O 4 nanowires to prepare ordered NiO/NiFe 2 O 4 nanocomposites. X-ray diffraction, N 2 adsorption-desorption, transmission electron microscopy and energy dispersive spectrometer were used to characterize the microstructure of the as-prepared samples. All results indicated that mesoporous NiFe 2 O 4 nanowires presented in bundle with the pore-volume percent of about 42% and NiO nanoparticles existed in the mesopores. The magnetic behavior of NiFe 2 O 4 nanowires and NiO/NiFe 2 O 4 nanocomposites were investigated with superconducting quantum interference device, and the saturation magnetization decreased with the increasing NiO content, while the coercivity and exchange bias field increased. The exchange bias effect was obviously observed for the NiO/NiFe 2 O 4 nanocomposites at low temperature and increased with the NiO content. It's concluded that interfaces magnetic interactions and surface energy barrier of NiO nanoparticles greatly affected the magnetic behavior of the NiO/NiFe 2 O 4 nanocomposites.

Mesoporous n-type hematite bunched nanowires (α-Fe2O3 BNWs) and Zn-, In- and Sn-doped α-Fe2O3 BNWs were synthesized by nanocasting method, and then the influence of the different-valence metals-doping on the microstructures, components and gas-sensing properties is discussed in detail. All samples present mesoporous-structure and are composed of the uniform α-Fe2O3 nanowires. The Zn, Fe, Sn and In-doped concentration decreased with the increasing radius of their hydrated ions. The ethanol gas-sensing results indicate that the different-valence metals-doping greatly affects the response of α-Fe2O3 BNWs sensors to ethanol gas. The sensitivity to 100 ppm ethanol gas increased from 10.046 for Fe1.896Zn0.104O2.948 BNWs sensor up to 45.556 for Fe1.938Sn0.062O3.031 BNWs sensor with the increasing metal valence. The high-valence Sn-doping not only decreases the ground state resistance, but also reduces barrier and work function of α-Fe2O3 BNWs, which results in the improved the sensitivity of α-Fe2O3 BNWs.

Photocatalytic Bi2WO6 and magnetic Fe3O4 nanoparticles were synthesized with hydrothermal process, and then were bonded together with polyethylene glycol and oxidized to form Fe3O4/Bi2WO6 and γ-Fe2O3/Bi2WO6 nanocomposites. The microstructure, component, magnetic response and photocatalytic degradation to ciprofloxacin (CIP) were studied with x-ray diffraction, N2 adsorption-desorption isotherms, energy dispersive spectrometer, vibrating sample magnetometer and UV/Vis spectrophotometer. Bi2WO6 nanoparticles presented the highest CIP removal of about 98% in 120 min under visible light irradiation, which was higher than that of Fe3O4/Bi2WO6 (90%) and γ-Fe2O3/Bi2WO6 (65%) nanocomposites. Both Bi2WO6-based nanocomposites could be easily separated by external magnetic field in 1 min. Fe3O4/Bi2WO6 nanocomposites showed the better synergistic effect of magnetic response and photocatalytic performance under visible light irradiation. Moreover, the photocatalytic mechanism for magnetic nanocomposites was deduced based on the energy band theory of semiconductor heterojunction contact.

A facile and easily reproducible laser ablation method has been developed to synthesize high quality Mn3O4 nanoparticles from Mn pieces in ambient air. By changing the laser ablation air pressure to ~20 Pa, a mixture of α-Mn and Mn3O4 composite nanoparticles were obtained. Most of the Mn3O4 nanoparticles are spherical in shape size ranging from 20 to 90 nm. Besides spherical shape, a considerable amount of α-Mn/Mn3O4 nanoparticles show irregular shape and aggregation. The oxide nanoparticles exhibit large coercivity up to 1.05 T, which is almost four times to that of the Mn3O4 single crystals, owing to size effect. The coercivity was further enhanced to 1.17 T in α-Mn/Mn3O4 nanoparticles, owing to the additional interfacial effect between α-Mn and Mn3O4 besides size effect. The presence of the antiferromagnetic/ferrimagnetic α-Mn/Mn3O4 interface results in an exchange bias field up to ~65 mT in the nanoparticles.

The characteristics of nat .,7 LiF:Mg,Cu,P thermoluminescent detectors exposed to high-energy 12 C (165 MeV/nucleon) ions and 60 Co γ -rays have been investigated. Through a careful analysis of the glow curves by the GlowFit program, it is found that the relative amplitude of satellite peaks 3, 5, 6 and 7 to peak 4, measured after irradiated with high-energy 12 C ions, is higher than that with 60 Co γ -rays for both types of TL detectors. It is observed that nat .,7 LiF:Mg,Cu,P thermoluminescent detectors would also exhibit a good linear dose response when the delivered dose of high-energy 12 C ions is in the range from 100 mGy to 1600 mGy. Furthermore, the relative efficiency of the nat .,7 LiF:Mg,Cu,P thermoluminescent detectors is independent of the absorbed dose in the linear dose response range. Compared to previously published data, the relative efficiency of the 7 LiF:Mg,Cu,P TL detectors decreases with increasing LET values.

The neutron yield from thick target of Pb irradiated with 250 MeV protons has been studied experimentally. The neutron production was measured with the water-bath gold method. The thermal neutron distributions in the water were determined according to the measured activities of Au foils. Corresponding results calculated with the Monte Carlo code MCNPX were compared with the experimental data. It was found out that the Au foils with cadmium cover significantly changed the spacial distribution of the thermal neutron field. The corrected neutron yield was deduced to be 2.23 +/- 0.19 n/proton by considering the influence of the Cd cover on the thermal neutron flux. (C) 2014 Elsevier B.V. All rights reserved.

The magnetic Co3O4 nanowires were synthesized using the templates of SBA-15, and then the well-dispersed nanowires (D-wires) were separated from the bundled ordered nanowires (B-wires) with the centrifugal technique. TEM images indicated that D-wires were highly dispersed Co3O4 nanowires and B-wires existed in bundles. All samples possessed the antiferromagnetism and superparamagnetism at high temperature. After revealing the intrinsic magnetic properties of Co3O4 nanowires with D-wires, the magnetic behavior of B-wires was discussed in detail, and then the magnetic interaction between neighboring nanowires could be deduced. The exchange bias effect from the body Co3O4 antiferromagnetism and surface ferromagnetism was observed at low temperature. The magnetization of B-wires was higher than that of D-wires, which was attributed to the constraint of the surface spin coupling between the neighboring nanowires to the surface affect of nanostructures.

MnBi 1-x Ti x (x = 0, 0.4, 0.7, 1) alloys were prepared by arc-melting, followed by heat treatment. X-ray diffraction (XRD) and vibrating sample magnetometer (VSM) were used to measure and investigate the phase structure and magnetic properties. The temperature dependent magnetization curves indicate that the phase transitions between LTP and HTP MnBi occur with heating or cooling in MnBi 1-x Ti x (x ≤ 0.7) samples. However, MnTi samples are in Mn₂Ti single-phase, with very low magnetic properties. Furthermore, the coercivity exhibits a positive temperature coefficient. The results show that the optimal content of Ti for the coercivity of MnBi 1-x Ti x alloy is x = 0.4. For MnBi sample, the coercivity reaches a maximum value of 1.13 T at 550 K. However, the remanence and energy product show apparent decrease with the addition of Ti in MnBi 1-x Ti x alloys.

This paper studies the effects of A-site substitution by barium on the magnetic and magnetocaloric properties of Pr 0.5 Sr 0.5-x Ba x MnO₃ (x = 0, 0.04, 0.08 and 0.1). The tetragonal crystal structures of the samples are confirmed by room temperature X-ray diffraction. The dependence of the Curie temperature (T C ) and the magnetic entropy change (ΔS M ) on the Ba doping content has been investigated. The samples of all doping contents undergo the second order phase transition. As the concentration of Ba increased, the maximum entropy change (|ΔS M | max ) increased gradually, from 1.15 J kg ?1 K ?1 (x = 0) to 1.36 J kg ?1 K ?1 (x = 0.1), in a magnetic field change of 1.5 T. The measured value of T C is 265 K, 275 K, 260 K and 250 K for x = 0, 0.04, 0.08 and 0.1, respectively. If combining these samples for magnetic refrigeration, the temperature range of ~220 K and 290 K, where |ΔS M |max is stable at ~1.27 J kg ?1 K ?1 and RCP = 88.9 Jㆍg ?1 for ΔH = 1.5 T. Pr 0.5 Sr 0.5-x BaxMnO₃ compounds, are expected to be suitable for magnetic-refrigeration application due to these magnetic properties.

The influences of Gallium doping on the magnetic microstructures and corrosion behaviors of Nd-Fe-B-Ti-C alloys are investigated. The cooling rate for obtaining fully amorphous structure is raised, and the glassforming ability is improved by the Ga addition. The High Resolution Transmission Electron Microscopy image shows that the α-Fe and Fe3B soft magnetic phases become granular surrounded by the Nd2Fe14B hard magnetic phase. The rms and (Δ?)rms value of Nd-Fe-B-Ti-C nanocomposite alloy thick ribbons in the typical topographic and magnetic force images detected by Magnetic Force Microscopy(MFM) decreases with 0.5 at% Ga addition. The corrosion resistances of Nd9Fe73B₁₂.6C ₁.₄Ti₄-xGax (x = 0, 0.5, 1) alloys are enhanced by the Ga addition. It can be attributed to the formation of more amorphous phases in the Ga doped samples.

The magnetic properties and magnetocaloric effect have been studied in Pr0.5Sr0.5−xLixMnO3 (0≤x≤0.3) prepared by conventional solid-state reaction. Magnetic measurements versus temperature revealed that the Curie temperature (TC) increased gradually with increasing lithium content (0.05≤x≤0.2); TC values are about 260 and 290 K for x=0.05 and 0.2, respectively. But it shows abrupt drop in TC value for x=0.3 (TC=235 K). Meanwhile, the paramagnetic–ferromagnetic (PM–FM) transition is second-order in x≤0.2, it changes into first order for x=0.3. However, the magnitude of the isothermal magnetic entropy (ΔSM) increased gradually. In a magnetic field change of 15.0 kOe, the maximum ΔSM achieved around TC are −1.03, −1.05, −1.48, −2.17 and −2.64 J kg−1 K−1 for x=0, 0.05, 0.1, 0.2and 0.3, respectively. Although ΔSM for x=0.2 is smaller compared to the composition x=0.3, the relative cooling capacity (RCP) 59.6 J kg−1 is similar compared with the value 59.8 J kg−1 for x=0.3. Addition of suitable TC makes it a desirable material for room temperature magnetic refrigeration.

In this paper, the magnetic properties and magnetocaloric effect in La0.7Sr0.3Mn1−xCoxO3 prepared by conventional solid state reaction have been studied. The samples have rhombohedra crystal structure as was determined by room temperature X-ray diffraction. From the measurements, it was found that the Curie temperature (TC) and magnetic entropy change (ΔSM) are strongly dependent on the Co content. The Curie temperature was found to be 338, 300 and 260 K for x=0, 0.05 and 0.1, respectively. Although the variation of maximum entropy change shows a similar tendency with TC, the phase transition temperatures were widened and the |ΔSM|max values, under a change of the magnetic field of 15 kOe, amount to −1.36, −1.17 and −0.92 J/kg K for x=0, 0.05 and 0.1, respectively. The results suggest that Mn-site substitution should be used to tailor Curie temperature and achieve large relative cooling power (RCP).

The influence of monovalent doping on the magnetocaloric effect (MCE) and refrigerant capacity or relative cooling power (RCP) of Pr 0.5 Sr 0.3 M 0.2 MnO 3 (M=Na, Li, K and Ag) materials has been investigated. A large magnetocaloric effect was inferred over a wide range of temperature around the second order paramagnetic–ferromagnetic transition. The maximum magnetic entropy changes (Δ S M ) reached 1.8, 2.2, 1.6 and 2.1 J/kg K and the relative cooling power (RCP) approached 58.9, 59.3, 69.6 and 54.6 J/kg for Na, Li, K and Ag doped materials in the magnetic change of 15 kOe, respectively. According to the results determined by the Maxwell relation, the magnetic entropy change fits well with the Landau theory of phase transition above T C for Pr 0.5 Sr 0.3 Li 0.2 MnO 3 . The large magnetic entropy change induced by low magnetic field suggested that these materials are beneficial for practical applications.

Retention, Recovery and Recycling of Metal Values from High Alloyed Steel SlagsThe work was carried out in four parallel directions. The thermodynamic activities of oxides of Cr in steel slags were determined by slag-gas equilibration technique. The ratio of Cr2+/Cr3+in CaO-MgO(-FeO)-AlO3-SiO2-CrO×system slags was measured by X-ray absorption near edge spectra (XANES). High-temperature mass spectrometry method was also used to obtain the distribution of chromium oxides. A mathematical correlation was established for estimating the ratio of Cr2+/Cr3+as a function of temperature, partial pressure of oxygen and slag basicity. Laboratory investigations of the decarburization of high alloy steels under controlled oxygen potentials have been carried out to retain Cr in the steel phase. A mathematical model has been developed for the decarburization process with controlled oxygen partial pressure. Experimental and theoretical investigations have been carried out in optimizing the Mo-additions to steel in the EAF practice in Uddeholm Tooling AB. Substantial saving of Mo as well as less emissions of Mo-bearing dust are indicated in the study. A salt extraction process was developed to extract the metal values from steel slags. Successful extractions, followed by electrolysis indicate that this could be a viable route towards recovery of metals from metallurgical slags.

Mesoporous titanium dioxides nanoparticles (TiO2 NPs) were synthesized using activated carbon (AC) as templates after the decomposition of AC. All results indicated that TiO2 NPs with the small grain size presented the anatase phase structure. Mesoporous TiO2 NPs showed the high surface area and the surface area decreased with the TiO2 content. The removal of methylene blue (MB) indicated that the photocatalytic decomposition efficiency of mesoporous TiO2 NPs increased up to 92% for three-times doping with the TiO2 content, and then decreased. This should be attributed to the synergistic effect from the MB adsorption of mesoporous-structure and the photocatalysis of TiO2 NPs. Therefore, the higher MB concentration near TiO2 NPs from the mesoporous-structure increased the touch chance and the MB photocatalytic decomposition was promoted greatly.

y Ba 6−3 x Eu 8+2 x Ti 18 O 54 + (1−y)Ba 6−3 x Sm 8+2 x Ti 18 O 54 ( x = 2 3 , y=0.1) (BEST) ceramic powders were synthesized by the Pechini method using ethylenediaminetetraacetic acid (EDTA) as a chelating agent. A flaxen, molecular-level, homogeneously mixed gel was prepared, and transferred into a porous resin intermediate through charring. Two-phase and well-crystallized BEST powders were prepared by calcination of the resin intermediate, without formation of any intermediate phases. Meanwhile, the crystal structure was determined by X-ray diffraction, which can be used to explain the microwave dielectric properties of BEST. The BEST ceramics prepared via EDTA precursor has good microwave dielectric characteristics: e r =52.36, Q f =2850 GHz and τ f =−24.56 ppm °C −1 .

Based on the Wentzel-Kramer-Brillouin modal condition, the phase shift of the bottom reflection coefficient can be extracted. The required input data for this inversion is the modal wavenumber. In this paper, the amount of phase shift of the bottom-reflection coefficient is estimated from the 2001 Asian Sea International Acoustic Experiment data in the East China Sea, in the frequency range of 100-200 Hz. Modal wavenumbers are estimated from using the cross-spectrum density matrix (CSDM) of reverberation data and a mode-shooting method. The error associated with the estimated phase shift is also discussed.

A series of FePt films with different film thickness are deposited on Pb(Mg1/3Nb2/3)O3–PbTiO3 (PMN-PT) substrates. A standard symmetric ‘Butterfly’ shaped ΔM/M-Edc loops is obtained in 8 nm FePt/PMN-PT heterostrucuture via strain mediated magnetoelectric coupling. For the 3 nm FePt/PMN-PT heterostructure, the loop-like in-plane magnetization (M) -E curve shares a similar shape with the electric polarization of PMN-PT as a function of electric field. The value of MS shows a dramatic change of 30.9% with Edc changing from 0 to 8 kV/cm, this giant magnetoelectric effect in 3 nm FePt/PMN-PT heterostructure results from the remnant polarization induced charge on FePt/PMN-PT interface via the screening charge effect. The enhanced magnetoelectric coupling in thin magnetic/ferroelectric heterostructures opens a promising avenue for the design of ultralow power magnetoelectric devices and information storage devices.

In this paper, ordered mesoporous SBA-15 silica was synthesized by the hydrothermal method, and then a series of CoFe2O4/SBA-15 nanocomposites were synthesized by a facile impregnation method. X-ray diffraction and N2 adsorption–desorption isotherms were used to characterize the microstructure and morphology of SBA-15 and CoFe2O4/SBA-15 nanocomposites. CoFe2O4 nanoparticles presented spinel phase structure and existed in the mesopores of SBA-15. The magnetic response of CoFe2O4/SBA-15 nanocomposites was characterized with vibrating sample magnetometer (VSM). The adsorption efficiency of CoFe2O4/SBA-15 nanocomposites for methylene blue increased firstly with the increasing CoFe2O4 content, and then decreased. Sample-2 (SBA-15: CoFe2O[Formula: see text]: 0.1 in the precursor) not only presented the best adsorptive performance, but also could be separated and retrieved effectively by magnetic separation technique.

Nucleoside triphosphate pyrophosphohydrolase (NTP-PPase) functions as one of the mechanisms to guarantee the fidelity of DNA replication through the cleavage of non-canonical nucleotides into di- or monophosphates. Human NTP-PPase is poorly understood and investigated. In the present study, by using tissue microassays with the paired cancer and adjacent regions, we found that with the prevalent expression of dCTP pyrophosphohydrase (DCTPP1) in the cytosol and nucleus in tumors investigated, DCTPP1 was inclined to accumulate in the nucleus of cancer cells compared to the paired adjacent tissue cells in multiple carcinoma including lung, breast, liver, cervical, gastric and esophagus cancer. More significantly, the higher DCTPP1 expression in the nucleus of lung, gastric and esophagus cancer cells was associated with histological subtypes. The nucleic accumulation of DCTPP1 was apparently observed as well when cancer cell line MCF-7 was treated with H2O2 in vitro. Considering the roles of DCTPP1 on restricting the concentration of non-canonical nucleotides in the nucleotide pool, accumulation of DCTPP1 in the nucleus of cancer cells might suffice for maintaining the proper DNA replication in order to fulfill the requirement for the survival and proliferation of tumor cells.

This study has presented a new classifier - the Partial Least Squares (PLS) classifier including linear and nonlinear based on the Partial Least-Squares Regression theory, then explained the classification algorithm and process of this new classifier, and finally, them have been applied to classify Landsat TM remote sensing data. Results of PLS linear classifier showed that there exist many classify mistake among six kinds of land use types. On the contrary, the nonlinear classifier based on Gaussian kernel function got better classification result, the overall classification accuracy is 79.297% and overall Kappa statistics is 0.74213. So, to remote sensing classification, the nonlinear PLS classifier is basic feasible, however, it is necessary for us to improve its algorithms or learning process further.

Nanocomposite alloys with the nominal compositions Nd x Y6-x Fe68Mo4B22 (x=1–5) were prepared directly by devitrification of amorphous rods and ribbons. The effect of Y doping on the glass-forming ability (GFA) of the alloys has been investigated. It was found that the GFA of the alloys was enhanced by the substitution of Y for Nd and increased with increasing Y content. The best glass former was Nd1Y5Fe68Mo4B22 with a critical diameter of 4 mm. A comparison of microstructures and magnetic properties between ribbon and bulk magnet with the same composition after optimally annealing treatment was presented in detail. Compared to the Nd3Y3Fe68Mo4B22 ribbons, the better hard magnetic properties have been obtained in the Nd3Y3Fe68Mo4B22 nanocomposite bulk magnet, which can be attributed to much higher relative content of hard magnetic Nd(Y)2Fe14B phase in the crystallized rod sample.