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It is crucial to better understand the magnetization reversal process between soft and hard magnets and to achieve a high maximum energy product in thick composite multilayers. In this study, we find that the exchange interactions dominate in soft–hard-magnetic composite bilayers, while dipole interactions are predominant in soft–hard-magnetic composite trilayers. Based on the first-order reversal curve, magnetization reversal models are developed for both the thick composite bilayer and trilayer. Dipole interactions play an important role in the long range, resulting in higher coercivity and remanence in the thick trilayer. A multilayer in a stacked trilayer structure is achieved, which is composed of thick films with a perpendicular magnetic anisotropy at a thickness of up to 16 μm. The enhanced dipole interactions lead to a remanent polarization of 1 T and a maximum energy product of 22.5 MGOe. This work contributes to the preparation of thick films with a high maximum energy product for applications in magnetic microelectromechanical systems. [ABSTRACT FROM AUTHOR]

Magnetic properties and coercivity mechanism of an anisotropic Ce–Nd–Fe–B film with a high Ce content (70 at. % Nd is replaced by Ce) have been investigated. After grain boundary diffusion with Tb layers, an enhancement of coercivity from 4150 to 9250 Oe is observed. Combining the initial magnetization curves, micromagnetic theory, and in-siut observation of magnetic domains in the demagnetization process, it is confirmed that the coercivity mechanism for the high-Ce-content magnets is the mixed type dominated by the pinning mechanism. Moreover, as the thickness of the Tb diffusion layer increases, the pinning center of domain walls changes from narrow planar inhomogeneities to wide planar inhomogeneities. A growing role of pinning plays in determining the coercivity of samples with increasing the thickness of Tb layer due to the increase in magnetocrystalline anisotropy after Tb substitution in the RE2Fe14B phase. In addition, the CeFe2 intergranular phase leads to the enhancement of coercivity due to decoupling the hard magnetic phase grains. Our results provide an insight into the coercivity mechanism of high-Ce-concentration Ce–Nd–Fe–B magnetic materials and promote the comprehension of the effect of Tb diffusion in the magnetization reversal process. [ABSTRACT FROM AUTHOR]

In composite magnets, an in-depth understanding of magnetization reversal behaviors promotes optimizing the structure design of a magnet and improving its performance. In this work, the perpendicular magnetic anisotropic Ta/La–Pr–Fe–B/Dy/La–Pr–Fe–B/Ta multilayers have been prepared by adjusting the thickness of the Dy layer. The domain reversal evolutionary procedure has been investigated in different aspects including the characterization of domain morphology, micromagnetic analysis, and irreversible reversal distribution. It is confirmed that the nucleation mechanism is dominant in determining the coercivity of the multilayers with Dy diffusion. Dy diffusion helps to enhance the coercivity of the multilayers. The formation of Dy-containing hard magnetic phases and rare-earth-rich grain boundary phases by adding the Dy element leads to a strong nucleation field and isolation of hard magnetic phase grains, respectively. Our results aid in the understanding of magnetization reversal behaviors and enhance the magnetic properties of highly abundant rare-earth permanent magnetic multilayer films with the doping element. [ABSTRACT FROM AUTHOR]

For semi-crystalline polymer materials, the difference in chain structure often leads to different physical properties; therefore, in-depth analysis of the chain structure is of great significance. With the continuous development of advanced instruments, many research means have emerged to characterize the structure of molecular chains. Among them, fractionation techniques provide effectively structural information on inter- and intra-molecular comonomer distribution, branching degree, and sequence length, etc. This work briefly presents the history of developments of various classical fractionation means such as temperature-rising elution fractionation, stepwise crystallization and successive self-nucleation and annealing, while focusing on the present and future of their applications. [ABSTRACT FROM AUTHOR]

The effect of sintering process on the electrical properties of CaCu3Ti4O12 (CCTO) ceramic dielectrics were investigated in this paper. It was found that grain size is affected by sintering and the nonlinear current-voltage (I-V) property will decrease with the increased sintering time. Also, the frequency and temperature dependences of dielectric permittivity and loss in the ranges of 10-1-107 Hz and 130-270 K were studied. Two relaxation processes with activation energy of 0.51 eV and 0.10 eV, respectively, were found in the frequency dependence of tan δ and Cole-Cole planes, which can be interpreted in terms of insulating grain boundaries and semiconducting grains. It was suggested that grain boundary Maxwell-Wagner relaxation and ionization of oxygen vacancy VO++, proposed as extrinsic and intrinsic relaxations, are responsible for the dielectric behaviors of CCTO ceramics. [ABSTRACT FROM AUTHOR]

The effect of an ultrathin W interlayer on the perpendicular magnetic anisotropy (PMA), spin orbit torque (SOT), and SOT-induced magnetization switching of Ta/CoFeB/MgO films has been investigated. Both the anisotropy energy density and the spin-torque efficiency are enhanced by inserting the ultrathin W interlayer. The results suggest that the large enhancement of the spin-torque efficiency originates from the increase in the interfacial spin transparency using a simplified drift-diffusion model. The minimum in-plane field required for SOT-induced complete switching is reduced to 12 Oe for the sample with the W interlayer, which is confirmed by polar Kerr microscopy. The reversed domain nucleation and propagation of the reversal processes have been observed by Kerr imaging. It is concluded that the ultrathin W interlayer increases the spin transmission and reduces the strength of the Dzyaloshinskii–Moriya interaction. Our result suggests that the interface modification is an efficient way to modulate the PMA and SOT. [ABSTRACT FROM AUTHOR]

Spin-orbit torques (SOTs) and the perpendicular magnetic anisotropy (PMA) in Ta/W/CoFeB/MgO structures have been investigated by varying the thickness of the W layer. Addition of the W layer gives rise to enhancement of the annealing stability and perpendicular anisotropy field. After annealing at high temperature, a high-resistivity is obtained for samples with W layer (up to 2 nm thickness), which indicates the existence of β-W phase. A giant spin Hall angle of 0.50 is found in Ta/W/CoFeB/MgO structures with a 2 nm W layer by using the harmonic Hall voltage measurement. The lowest switching current density of 6 MA/cm2 is achieved in the sample with 1 nm W layer, indicating that a strong interfacial spin Hall effect may exist in the CoFeB/W interface. The study may provide a way to obtain simultaneously a large PMA as well as a high efficiency of SOTs. [ABSTRACT FROM AUTHOR]

The combustion of anthracite and bituminite blends with different bituminite particle size was investigated with thermogravimetric analysis (TGA). It is indicated in the results that the increase of bituminite particle size may influence the pyrolysis of blends and consequently the decomposition of blends moved to higher temperature zones with the increase of bituminite particle size. However, the negative influence of specific area is not that significant to some bituminite and anthracite mixtures, the comprehensive combustion behavior of blends was stable when particle size of some bituminie PC was increased from 0,074 mm to 0,150 mm. [ABSTRACT FROM AUTHOR]

Although a variety of factors underlying diapause have been identified in arthropods and other organisms, the molecular mechanisms regulating diapause are still largely unknown. Here, to better understand this process, we examined diapause-associated genes in the two-spotted spider mite, Tetranychus urticae, by comparing the transcriptomes and proteomes of early diapausing and reproductive adult females. Amongst genes underlying diapause revealed by the transcriptomic and proteomic data sets, we described the noticeable change in Ca2+-associated genes, including 65 Ca2+-binding protein genes and 23 Ca2+ transporter genes, indicating that Ca2+ signalling has a substantial role in diapause regulation. Other interesting changes in diapause included up-regulation of (1) glutamate receptors that may be involved in synaptic plasticity changes, (2) genes involved in cytoskeletal reorganization including genes encoding each of the components of thick and thin filaments, tubulin and members of integrin signalling and (3) genes involved in anaerobic energy metabolism, which reflects a shift to anaerobic energy metabolism in early diapausing mites. [ABSTRACT FROM AUTHOR]

Produced water from polymer flooding was much more difficult to be treated than that from water flooding. The mechanisms of polymer stabilizing the oil-in-water emulsion were the decreases of interfacial tension and electric conductivity, and the increases of zeta potential and bulk phase viscosity. Inorganic flocculant, the combination of inorganic flocculant and polymer degradation agent, and the combination organic flocculant and coagulant were used to break the oil-in-water emulsion stabilized with polymer. It was the most effective way to use the combination of organic flocculant and coagulant for treating polymer stabilizing oil-in-water emulsion. [ABSTRACT FROM PUBLISHER]

A highly selective and sensitive method was developed for the simultaneous determination of four β-agonists (clenbuterol, salbutamol, ractopamine and terbutaline) in beef by immunoaffinity chromatography purification coupled to ultra-high-performance LC-MS/MS. The MS/MS conditions, ultra-high-performance LC mobile phase, injection solution, sample purification process and matrix effect were studied to optimise the operation conditions. The limits of detection (LODs) of the instrument for the studied β-agonists ranged from 0.20 to 0.25 µg l−1, and the LODs of the method for the studied β-agonists ranged from 0.20 to 3.00 µg kg−1 for beef. Calibration curves were constructed using a standard solution diluted with blank beef matrix. The linear ranges of the calibration curves ranged from 5 to 100 µg kg−1 and the coefficients of determination were >0.9942 (n = 10) for all four β-agonists. Samples spiked at 5, 10 and 50 µg kg−1 showed recoveries >72% and RSDs <6.6%. The method is suitable for the simultaneous detection of four β-agonists at trace levels in beef. [ABSTRACT FROM PUBLISHER]

The magnetic properties and the possible interaction mechanisms of anisotropic soft- and hard-magnetic multilayers have been investigated by altering the thickness of different kinds of spacer layers. The metal Ta and the insulating oxides MgO, Cr2O3 have been chosen as spacer layers to investigate the characteristics of the interactions between soft- and hard-magnetic layers in the anisotropic Nd-Dy-Fe-Co-B/α-Fe multilayer system. The dipolar and exchange interaction between hard and soft phases are evaluated with the help of the first order reversal curve method. The onset of the nucleation field and the magnetization reversal by domain wall movement are also evident from the first-order-reversal-curve measurements. Reversible/irreversible distributions reveal the natures of the soft- and hard-magnetic components. Incoherent switching fields are observed and the calculations show the semiquantitative contributions of hard and soft components to the system. An antiferromagnetic spacer layer will weaken the interaction between ferromagnetic layers and the effective interaction length decreases. As a consequence, the dipolar magnetostatic interaction may play an important role in the long-range interaction in anisotropic multilayer magnets. [ABSTRACT FROM AUTHOR]

A simple and fast analysis method to sort large data sets into groups with shared distinguishing characteristics is described and applied to single molecular break junction conductance versus electrode displacement data. The method, based on principal component analysis, successfully sorts data sets based on the projection of the data onto the first or second principal component of the correlation matrix without the need to assert any specific hypothesis about the expected features within the data. This is an improvement on the current correlation matrix analysis approach because it sorts data automatically, making it more objective and less time consuming, and our method is applicable to a wide range of multivariate data sets. Here the method is demonstrated on two systems. First, it is demonstrated on mixtures of two molecules with identical anchor groups and similar lengths, but either a π (high conductance) or a σ (low conductance) bridge. The mixed data are automatically sorted into two groups containing one molecule or the other. Second, it is demonstrated on break junction data measured with the p bridged molecule alone. Again, the method distinguishes between two groups. These groups are tentatively assigned to different geometries of the molecule in the junction. [ABSTRACT FROM AUTHOR]

Mic rotopography and combustion characteristics of carbonized corn straw and pine charcoal as well as anthracite were investigated to compare the property of fuel and analyze the application of corn straw in industrial activity. The reduction process of hematite with different reducing agent was studied with thermogravimetric analysis. It is indicated in the results that the initial reduction temperature was lower when carbonized corn straw was blended with hematite and an ideal reduction rate can be achieved with a C/O of 1.1, while the reduction rate of pine charcoal to hematite was lower and higher C/O is needed for anthracite to obtain the same reduction rate. [ABSTRACT FROM AUTHOR]

In fluence of microwave irradiation on gasification behavior and crystallite parameters of coke samples was studied in this research. The results indicated that microwave irradiation have significant influence on the carbon structure and the reactivity of coke in CO2 atmosphere. The thermogravimetric results showed that the temperature of coke at different conversion rates of 10 %, 20 % and 30 % were reduced by 20 °C, 30 °C and 50 °C respectively. Simultaneously, microwave irradiation may lead to variation in lateral size and stacking height of crystallite and subsequently reduce the gasification reaction rate of coke in CO2 atmosphere. [ABSTRACT FROM AUTHOR]

Magnetic vortices in patterned nanocomposite structures have been studied. A double-vortex structure consisting of two vortex cores with opposite chiralities and two edge half-vortices is realized in a micron-size circular disk, which consists of [Co/Pd]7/Ru/Py. A systemic study of the magnetization reversal of a double-vortex state and a single vortex state in an out-of-plane applied field has been performed by means of magnetic force microscopy. It is found that the interlayer exchange and dipolar interactions are critical for nucleation and annihilation of the double-vortex and the single vortex states. Micromagnetic simulations prove that the double-vortex state can stably exist in a patterned nanocomposite structure. Magnetic configurations ranging from the double-vortex and single vortex states to other multidomain states and the in-plane single-domain state are observed. The dependence of the magnetic configuration on the thickness of the soft-magnetic layer and spacer layer is presented in an experimental phase diagram. The results can significantly widen the practical applications of vortices on the three-dimensional spintronic memory and logic devices. [ABSTRACT FROM AUTHOR]

In this work, Zn particles with magnetic shell were synthesised and investigated. Zn particles with different sizes were synthesised by arc-discharge method, and then the Zn particles were put in a suitable concentration of FeSO4 solution with a surface active agent. After some time, the Zn particles with magnetic shell were produced. The particles contain oxygen shell probably in the form of FeO and ZnO, while the core material is Zn. From the saturation magnetisation at room temperature and transmission electron microscopy (TEM) images, it is noticed that the FeO was first formed on the surface of Zn and then ZnO appeared with increasing reaction time. The microwave absorption is not as good as that reported in other materials, because of the weak magnetisation and the faulty core-shell structure formed by metal core and magnetic shell. [ABSTRACT FROM AUTHOR]

We report on the magnetotransportproperties of chemical vapordeposition grown films of interconnected Bi2Te3nanoplates. Similar to many other topological insulator (TI) materials,these granular Bi2Te3films exhibit a linearmagnetoresistance (LMR) effect which has received much recent attention.Studying samples with different degree of granularity, we find a universalcorrelation between the magnitude of the LMR and the average mobility(⟨μ⟩) of the films over nearly 2 orders of magnitudechange of ⟨μ⟩. The granularity controlled LMReffect here is attributed to the mobility fluctuation induced classicalLMR according to the Parish–Littlewood theory. These findingshave implications to both the fundamental understanding and magnetoresistivedevice applications of TI and small bandgap semiconductor materials. [ABSTRACT FROM AUTHOR]

This paper presents a microfluidic system enabling continuous characterization of instantaneous Young's modulus (Einstantaneous) of single cells in suspension. In this study, cells were aspirated continuously through a constriction channel while cellular entry processes were monitored using a high-speed camera. Numerical simulations were conducted to model cellular entry process into the constriction channel where a visco-hyperelastic solid was used to model biological cells and the cellular friction with the constriction channel wall (ƒc) was properly addressed. Both experimental observations and numerical simulations confirmed the two-stage cellular entry process into the constriction channel: an instantaneous jump into the channel quantified by instantaneous aspiration length (Linstantaneous) followed by a creeping increase in aspiration length terminated by transitional aspiration length (Ltransitional). Numerical simulations reveal that Linstantaneous and Ltransitional are reversely proportional to Einstantaneous, which are affected by ƒc regardless of other cellular viscoelastic parameters. By combining measured Linstantaneous and Ltransitional with these obtained from numerical simulations, Einstantaneous and ƒc were quantified as 3.48 ± 0.86 kPa and 0.39 ± 0.11 for A549 cells (ncell = 199) and 2.99 ± 0.38 kPa and 0.37 ± 0.02 for 95C cells (ncell = 164). As a platform technology, this method can be used to characterize Einstantaneous of various cell types in a continuous manner for cellular biophysical property characterization. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma suppressor 1 (HCCS1) was discovered as a novel tumor suppressor gene. We recently observed that adenovirus-mediated gene transfer of HCCS1 leads to cytotoxicity to human hepatocarcinoma cells. Here, we have demonstrated that adenovirus-mediated overexpression of HCCS1 induces apoptosis in hepatocarcinoma cells and have further characterized the apoptotic cascade. The results showed that lysosomal cathepsin D is released into the cytosol in response to HCCS1 overexpression and consequently triggers Bax insertion into the mitochondrial membrane, which leads to the release of cytochrome c. In addition, HCCS1 overexpression can induce an increase in intracellular free Ca2+ concentration, which also results in cytochrome c release. The released cytochrome c activates downstream caspases, leading to the occurrence of the late stages of apoptosis. Moreover, we demonstrated that the disruption of HCCS1 in mice leads to embryonic lethality, accompanied by abnormal labyrinth architecture resulting from the excessive proliferation of trophoblast cells in the placenta. These results suggest that HCCS1 plays a role in apoptosis regulation and development.Cell Death and Differentiation (2008) 15, 1481–1490; doi:10.1038/cdd.2008.73; published online 30 May 2008 [ABSTRACT FROM AUTHOR]

Soy protein, in both intact and hydrolyzed forms, is widely used as the nitrogen source in infant and adult formulas. This protein is also consumed in vast quantities worldwide as soybean-based food products. Digestion is the rate-limiting step in the assimilation of proteins from the gut. As a result, intestinal transit must be slowed when a higher load of protein is available or when this nutrient is delivered in the intact rather than hydrolyzed form. However, little information is available on the effect of load and degree of hydrolysis of soy protein on intestinal transit and protein absorption. To test the hypothesis that inhibition of intestinal transit and protein absorption depend on the load of soy protein and the state of hydrolysis of this nutrient, we compared intestinal transit and protein absorption in dogs equipped with duodenal and midintestinal fistulas during intestinal perfusion with 0, 50, 100, or 200 g/L solutions of intact soy protein versus 0, 100, 200, 300, or 400 g/L solutions of hydrolyzed soy protein. We found that intestinal transit was slowed in a load-dependent fashion by intact (P < 0.001) and hydrolyzed (P < 0.05) soy protein. Soy protein inhibited intestinal transit more potently in the intact than hydrolyzed form (P < 0.05). A greater amount of protein was absorbed by the proximal half of the small intestine when soy protein was delivered in the hydrolyzed than intact form (P < 0.05), and the efficiency of protein absorption was maintained at a high and nearly constant level of 82.6 to 87.4% for intact soy protein and 89.0 to 92.3% for hydrolyzed soy protein. We conclude that in dogs intestinal transit and absorption of soy protein depend on the load and the degree of protein hydrolysis. [ABSTRACT FROM AUTHOR]