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A finite element (FE) model of particle reinforced metal matrix composite (PRMMC) was developed by considering load transfer, grain refinement, thermal residual stress/strain, plastic strain gradient and damage of the matrix together. This new model provides precise prediction of the tensile stress-strain curves of PRMMC, even when the size of particles varies. Using the new model, the effect of each strengthening mechanism was assessed quantitatively. According to the results, grain refinement is the main reason causing size effect, while strain gradient only causes higher work hardening rate for PRMMC with smaller particles. Load transfer plays a dominant role among other strengthening mechanisms. Residual stress/strain shows steady but small effect in strengthening PRMMC. [ABSTRACT FROM AUTHOR]

Highlights • First experimental study on dynamic mixed-mode fracture of fiber-reinforced concrete. • Experimental demonstration that the crack propagation may be stable or unstable depending on loading rate and fiber content. • Fracture is mainly transgranular, but maybe inter- or trans-granular at stable cracking. • Higher dynamic increase factor for peak loads for higher loading rate and fiber content. • Significant higher DIF for peak loads in mixed-mode that in mode I. Abstract The objective of this work is to study the influence of fiber content and loading rate on the dynamic mixed-mode fracture of self-compacting concrete. Three amount of steel fibers, 0%, 0.2%, 0.4% and 0.6% in volume ratio, were added to cast prismatic beams. Each beam was sawn at one quarter span to produce a half-depth notch. Three-point bending tests were performed at four loading rates: two (2.2 µm/s and 2.2 mm/s) with a servo-hydraulic machine; the other two (1.77 m/s and 2.66 m/s) through a drop-weight impact device. The latter ones were also recorded with a high-speed video camera to follow the crack propagation process. Results show that both the peak load and the crack inclination angle increase for faster loading rates. In addition, highly reinforced beams exhibit profuse crack branching. As the fiber ratio increases, it is also observed that the main crack may either bifurcate or abruptly change its path when it gets closer to the loading point. Numerical simulations based on an eigensoftening approach in a meshfree framework were also carried out to reproduce the observed phenomena. [ABSTRACT FROM AUTHOR]

This study investigated the protein changes in goat milk during the homogenization process using label-free quantification. We quantified 310 and 315 proteins in the control group (CG) and homogenized group (HG), respectively, and 16 proteins were significantly different between the 2 groups. For HG, the goat milk protein particle sizes were smaller and more evenly distributed and exhibited an increase in the regular arrangement of the secondary structures. Proteomics analysis verified that xanthine dehydrogenase and asparaginase-like 1 expression in CG were higher than in HG, whereas the opposite was observed for fructose-bisphosphate aldolase, κ-casein, and β-casein. Significant changes were found in the homogenization-treated goat milk proteome that were related to goat milk glycolysis/gluconeogenesis metabolism. This work provides updated information on the current proteome characteristics of homogenized goat milk, which may be important for applying the protein component of goat milk to human nutrition and health. [ABSTRACT FROM AUTHOR]

Abstract Bacterial fruit blotch (BFB) of cucurbits, caused by Acidovorax citrulli , is a major threat to commercial watermelon and melon production worldwide. At present, there are at least two genetically distinct sub-populations (group I and II) of A. citrulli that differ in host preference among cucurbit species and copper sensitivity. In this study, we analyzed the pilA gene sequences of 103 A. citrulli strains from China and other countries. Based on these data, we classified all tested A. citrulli strains into three types. The pilA -based type 1 strains in this study coincided with the previously established group I strains; while the type 2 strains coincided with group II strains. Ten strains that did not cluster with group I or II strains were classified into a new type, designated type 3. Based on differences in pilA sequences, we designed a multiplex PCR assay to distinguish the three A. citrulli pilus types. This multiplex PCR assay has proven to be viable for strain typing of 139 A. citrulli strains and for the detection of this pathogen in artificially inoculated seeds and leaves and naturally infected leaves and fruits. This assay proved to be rapid, accurate, reliable and applicable for early distinction of A. citrulli types associated with BFB epidemics. It may also inform the judicious and environmentally sound use of bactericides, especially copper-based compounds. Highlights • We divided Acidovorax citrulli strains into 3 types based on the pilA genes. • A multiplex PCR assay for 3 types of Acidovorax citrulli strains was developed. • Applications include the pathogen detection in weed washings and plant tissues. [ABSTRACT FROM AUTHOR]

Exchange bias and inverted hysteresis loops were observed in the Cr2O3 coated CrO2 particles with a wide distribution of the blocking temperature. The ferromagnetic coupling between the CrO2 cores and Cr2O3 shell is responsible for exchange bias observed below 292 K. In the temperature range of 261 K–∼340 K, the particles show inverted hysteresis loops, i.e., the negative remanence and coercivity. The most interesting observation is that the particles show an exchange-biased (or shifted) inverted hysteresis loops in between 261 K and 292 K; and that the maximum negative remanence appears at 292 K where exchange bias disappears. An antiferromagnetic type of interaction between the blocked particles and the superparamagnetic particles is believed to be responsible to the inverted hysteresis loops. [ABSTRACT FROM AUTHOR]

Preoperative radiotherapy (RT) is one of the recommended treatments for primary extremity and trunk soft tissue sarcoma, however, the pathological remission is relatively low, and survival is not improved. We hypothesized that the addition of tyrosine kinase inhibitor (TKI) will improve the pathological remission rate without significant increase of major wound complications (MWCs). Two phase II study were initiated in our center. Primary or recurrent non-metastatic extremity or trunk soft tissue sarcoma was enrolled. Patients received preoperative intensity-modulated radiotherapy (IMRT) of 50Gy in 25 fractions with concurrent and sequential Anlotinib (12 mg QD for 2 weeks, 3 cycles in total) or Apatinib (500 mg QD, 5 days per week, for 9 weeks in total), followed by wide resection. NCI-CTC 5.0, RECIST 1.1 criteria, and EORTC-STBSG criteria was used to evaluate acute toxicities, clinical response and pathological grading. The primary endpoint was defined as MWCs as per the SR2 criteria within 4 months post-surgery. From Jul 2020 to Dec 2021, 31 patients were enrolled and completed RT. The median onset age is 55 (22-82) years old. There are 26 and 5 patients with primary untreated and locally relapsed disease, respectively. The median tumor size is 10.5 (3.7-19.5) cm, with 23 patients (74.2%) larger than 8cm. Twenty-seven tumors (87.1%) were evaluated as unresectable or borderline resectable, which was defined as impossible or difficult to conserve limb with non-R2 wide resection. There were 21, 9 and 1 patients having Anlotinib, Apatinib and none, respectively. All except 5 took TKI as per protocol, with 4 patients having dose reduction due to Grade 3 toxicities. The observed ≥Grade 3 toxicities are: hypertension in 4 patients (19.1%) in Anlotinib group and 2 patients (22.2%) in Apatinib group, and one Grade 4 hepatotoxicity in Apatinib group (11.1%). There are 14 (14/30, 46.7%) and 16 patients (16/30, 53.3%) who achieved partial response (PR) and SD as per RECIST 1.1 criteria at 1-month post-radiotherapy, respectively. All the patients who had PR had obvious tumor shrink at the first 1 to 2 weeks during radiotherapy. Six out of 24 patients (25%) who underwent wide resection with at least 6 weeks follow-up had MWCs, with all in lower extremity. There were 4 (4/26, 15.4%), 3 (3/26, 11.5%) and 3 (3/26, 11.5%) patients achieving pathological Grade A, B, and C remission as per EORTC-STBSG criteria, respectively. All the 22 patients with unresectable or borderline resectable tumor had non-R2 limb-conserving wide resection, with 18 R0 and only 4 R1 resection. For patients with non-metastatic extremity or trunk primary sarcoma, the combination of TKI and pre-operative RT is safe and well-tolerated, and achieve favorable clinical and pathological response. The earlier response with addition of TKI made more patients with unresectable or borderline resectable tumor completely resected by limb-conserving wide resection. NCT05167994, NCT05235100 [ABSTRACT FROM AUTHOR]

Micro-perforated panel (MPP) absorber has been widely used in noise control and is regarded as a promising alternative to the traditional porous materials. However, the absorption bandwidth of single MPP absorbers is always insufficient to compete with the porous materials. In this paper, aiming at obtaining high absorption over broad frequency band, a compound MPP absorber array adopting the series-parallel coupling manner is proposed and investigated. Firstly, a theoretical model for the normal absorption coefficient of the series-parallel coupled MPP absorber is established based on the electrical circuit analysis. And then measurements of the normal incidence absorption coefficients are carried out to verify the theoretical predictions. The experimental data are in agreement with the theoretical calculation and prove that the composite structure has the characteristics of broadening the absorption bandwidth through a combination of serial and parallel coupling, which may provide a new technique to improve the absorption performance of such type of MPP absorbers. [ABSTRACT FROM AUTHOR]

Presents information on a study which looked at macroscopic resonant quantum tunneling of magnetization in antiferromagnetic ferritin particles. Discussion on the quantum dynamics of magnetization in ferritin; Description of the ferritin used in this study; Results of this study.

Fully dense Ti 5 Si 3 /TiAl composites were successfully in situ synthesized by reactive infiltration using Ti powders and Al–Si alloys as raw materials. Fine Ti 5 Si 3 particles exhibit a unique quasi-network distribution, remarkably hindering the coarsening of α 2 /γ lamellar colonies. Compared to the as-cast samples, the mean size of lamellar colonies is much finer and thus the resulting Ti 5 Si 3 /TiAl composites show the enhanced room temperature elongation, up to 2.5%, while retaining the ultimate tensile strength of 414 MPa. Moreover, Ti 5 Si 3 /TiAl composites display superior high temperature tensile properties. Consequently, the novel Ti 5 Si 3 /TiAl composites have potential for high temperature applications in aeronautics and aerospace. [ABSTRACT FROM AUTHOR]

Space-based electron detectors are commonly tested using radioactive β-sources which emit a continuous spectrum without spectral lines. Therefore, the tests are often to be considered only qualitative. This paper introduces a method, which results in more than a qualitative test even when using a β-source. The basic idea is to use the simulated response function of the instrument to invert the measured spectrum and compare this inverted spectrum with a reference spectrum obtained from the same source. Here we have used Geant4 to simulate the instrument response function (IRF) and a 3.5 mm thick Li-drifted Si detector to obtain the reference 90 Sr/ 90 Yi source spectrum to test and verify the geometric factors of the Omni-Direction Particle Detector (ODPD) on the Tiangong-1 (TG-1) and Tiangong-2 (TG-2) spacecraft. The TG spacecraft are experimental space laboratories and prototypes of the Chinese space station. The excellent agreement between the measured and reference spectra demonstrates that this test method can be used to quantitatively assess the quality of the instrument. Due to its simplicity, the method is faster and therefore more efficient than traditional full calibrations using an electron accelerator. [ABSTRACT FROM AUTHOR]

The material parameters of 17vol.%SiCp/2009Al composite in the Arrhenius-type constitutive equations were calculated using experimental data from hot compression tests. The constitutive equation was then implemented into the finite element software, ABAQUS/Explicit, to calculate the stress, deformation and edge damage in the hot rolling process. The initiation and propagation of edge cracks under the hot rolling condition were studied via the Gurson–Tvergaard–Needleman (GTN) damage model. The influence of the thickness reduction on the strip damage was assessed. The results indicate that the high tensile stress at the edge of the strip causes crack initiation and propagation, and the total reduction has a significant effect on the damage in the hot rolling of the SiCp/2009Al composites. When the reduction is less than 20%, no crack initiates and the damage occurs on the strip surface. With increase of the total reduction to 25% and larger, edge cracks occur and increase gradually. The distribution and direction of edge cracks are closely correlated with the stress components. The hot rolling experiments on 17vol.%SiCp/2009Al composite were conducted to evaluate the simulation results, and it is indicated that the finite element calculation results agreed well with the experimental results. This indicates that the finite element analysis is able to successfully simulate the rolling process and provide important information for the process optimization. [ABSTRACT FROM AUTHOR]

Finite treatment with nucleos(t)ide analogues (NAs) remains a great challenge for chronic hepatitis B in the clinic. This study aimed to investigate the relationship between intrahepatic quasispecies heterogeneity and the NAs off-treatment outcomes in a prospective cohort. Eighteen HBeAg-positive patients with chronic hepatitis B who achieved the cessation criteria underwent liver biopsy, and stopped treatment thereafter. Patients were followed up prospectively for 1 year. The reverse transcriptase (RT) gene of intrahepatic hepatitis B virus (HBV) was cloned and sequenced. Intrahepatic quasispecies heterogeneity and specific gene mutations were analysed using bioinformatic methods. Ten patients achieved sustained response, and eight patients developed viral relapse. The intrahepatic quasispecies Shannon entropy and nucleotide diversity within either RT or the surface (S) region of patients with sustained response were significantly higher (p < 0.05) than those of patients who had a viral relapse. Intrahepatic quasispecies Shannon entropy at the nucleotide level predicted the sustained off-treatment response (area under receiver operating characteristics curve 0.925; 95% CI 0.807–1.000; p 0.003). More positive selection sites and N -glycosylation mutations within the S region were found in patients with sustained response than in the patients with viral relapse (p < 0.01). Most of the positive selection sites in patients with sustained response were located in reported HLA-I-restricted or HLA-II-restricted epitopes. Intrahepatic quasispecies heterogeneity at the end of treatment was correlated with off-treatment outcomes in HBeAg-positive patients with chronic hepatitis B. More immune escape mutations were found within the S region in patients with sustained response. The higher intrahepatic quasispecies heterogeneity indicated a more robust immune control over HBV, which in turn maintained a sustained response after withdrawal of NAs. [ABSTRACT FROM AUTHOR]

A three-dimensional flower-like structure NiO and NiO-based nanocomposites (NiO@C and NiO/Ni) are synthesized with an ingenious fabrication technique followed by calcinating process in N 2 atmosphere. The mesocrystal structure and surface morphology are tested with the X-ray diffraction, scanning electron microscope and transmission electron microscope methods. As the anode materials for lithium-ion batteries, the as-prepared three-dimensional flower-like NiO/Ni and NiO@C nanocomposites maintain reversible discharge capacities of 846 mAh g −1 and 739 mAh g −1 , respectively, after repeated cycling at a current density of 1 A g −1 over 100 cycles. The rate performance of the NiO/Ni nanocomposites is better than that of the NiO@C composites, and the bare NiO should be one of the worst. These results indicate that the transition metal oxide materials can be promising for anode materials in lithium-ion batteries after being composited with good conductor materials. [ABSTRACT FROM AUTHOR]

Polarized Raman spectroscopy was used to study the lattice structure of BiFeO 3 films on different substrates prepared by pulsed laser deposition. Interestingly, the Raman spectra of BiFeO 3 films exhibit distinct polarization dependences. The symmetries of the fundamental Raman modes in 50–700 cm −1 were identified based on group theory. The symmetries of the high order Raman modes in 900–1500 cm −1 of BiFeO 3 are determined for the first time, which can provide strong clarifications to the symmetry of the fundamental peaks in 400–700 cm −1 in return. Moreover, the lattice structures of BiFeO 3 films are identified consequently on the basis of Raman spectroscopy. BiFeO 3 films on SrRuO 3 coated SrTiO 3 (0 0 1) substrate, CaRuO 3 coated SrTiO 3 (0 0 1) substrate and tin-doped indium oxide substrate are found to be in the rhombohedral structure, while BiFeO 3 film on SrRuO 3 coated Nb: SrTiO 3 (0 0 1) substrate is in the monoclinic structure. Our results suggest that polarized Raman spectroscopy would be a feasible tool to study the lattice structure of BiFeO 3 films. [ABSTRACT FROM AUTHOR]

Abstract: The morphology and phase of self-assembled manganese oxides during different stages of thermal oxidation were studied. Very interesting morphological patterns of Mn oxide films were observed. At the initial oxidation stage, the surface was characterized by the formation of ring-shaped patterns. As the oxidation proceeded to the intermediate stage, concentric plates formed to relax the compressive stress. Our experimental results gave a clear picture of the evolution of the structures. We also examined the properties of the structures. [Copyright &y& Elsevier]

Abstract: Vertically aligned carbon nanotube field-effect transistors (CNTFETs) have been developed using pure semiconducting carbon nanotubes. The source and drain were vertically stacked, separated by a dielectric, and the carbon nanotubes were placed on the sidewall of the stack to bridge the source and drain. Both the effective gate dielectric and gate electrode were normal to the substrate surface. The channel length is determined by the dielectric thickness between source and drain electrodes, making it easier to fabricate sub-micrometer transistors without using time-consuming electron beam lithography. The transistor area is much smaller than the planar CNTFET due to the vertical arrangement of source and drain and the reduced channel area. [Copyright &y& Elsevier]

Abstract: TiO2–M–TiO2 (M=W, Co and Ag) multilayer films have been deposited on glass substrates using reactive magnetron sputtering, then annealed in air for 2h at 500°C. The structure, surface morphology and optical properties of the films have been studied using X-ray diffraction, Raman spectroscopy, atomic force microscopy and UV–vis spectroscopy. The TiO2–W–TiO2 and TiO2–Co–TiO2 films showed crystalline phases, whereas the TiO2–Ag–TiO2 films remained in the amorphous state. The crystallization temperature for the TiO2–M–TiO2 films decreased significantly compared with pure TiO2 film deposited on quartz. Detailed analysis of the Raman spectra suggested that the crystallization of TiO2–M–TiO2 films was associated with the large structural deformation imposed by the oxidation of intermediate metal layers. Moreover, the optical band gap of the films narrowed due to the appearance of impurity levels as the metal ions migrated into the TiO2 matrix. These results indicate that the insertion of intermediate metal layers provides a feasible access to improve the structural and optical properties of anatase TiO2 films, leading to promising applications in the field of photocatalysis. [Copyright &y& Elsevier]

Abstract: We systematically studied the anomalous Hall effect in a series of polycrystalline Ni films with thickness ranging from 4 to 200 nm. It is found that both the longitudinal and anomalous Hall resistivity increased greatly as film thickness decreased. This enhancement should be related to the surface scattering. In the ultrathin films (4–6 nm thick), weak localization corrections to anomalous Hall conductivity were studied. The granular model, taking into account the dominated intergranular tunneling, has been employed to explain this phenomenon, which can explain the weak dependence of anomalous Hall resistivity on longitudinal resistivity as well. [Copyright &y& Elsevier]

Abstract: In this study, an interval full-infinite mixed-integer municipal-scale energy model (IFMI-MEM) is developed for planning energy systems of Beijing. IFMI-MEM is based on an integration of existing interval-parameter programming (IPP), mixed-integer linear programming (MILP) and full-infinite programming (FIP) techniques. IFMI-MEM allows uncertainties expressed as determinates, crisp interval values and functional intervals to be incorporated within a general optimization framework. It can also facilitate capacity-expansion planning for energy-production facilities within a multi-period and multi-option context. Then, IFMI-MEM is applied to a real case study of energy systems planning in Beijing. The results indicate that reasonable solutions have been generated. They are helpful for supporting (a) adjustment of the existing demand and supply patterns of energy resources, (b) facilitation of dynamic analysis for decisions of capacity expansion and/or development planning, and (c) coordination of the conflict interactions among economic cost, system efficiency, pollutant mitigation and energy-supply security. [Copyright &y& Elsevier]

The microstructure and mechanical properties of extruded Mg–1.0Zn–0.5Ca alloys were studied. Observation of the microstructure indicates that the addition of Ca tends to weaken the extrusion texture. The results of tensile tests show that the alloy extruded at 643K exhibits remarkable elongation of 44% allied with strength of 215MPa. Moreover, the strength of the alloy extruded at 583K is increased to 300MPa. These superior properties can be attributed to grain refinement and the unique extrusion texture. [Copyright &y& Elsevier]

Abstract: This study aims to investigate the characteristics, provenance, and particle-related pollution of an intense dustfall event that occurred in Beijing on 16–17 April 2006. Satellite images reveal that the aeolian dust originated in northeastern Alxa League of Inner Mongolia and passed southeastward across northern Ningxia, middle Inner Mongolia, northern Shaanxi, Shanxi, and Hebei provinces. The dust then moved out of continental China in the vicinity of Beijing and Tianjin. The floating dust led to severe air pollution in Huhhot, Datong, and Beijing. We measured dustfall by collecting dust samples, investigated particle morphology, and calculated the mass medium diameter (MMD) of the dustfall using a scanning electron microscope (SEM). Major elements and mineral content of the dust particles were determined by electron probe and powder X-ray diffractometer, respectively. The relative abundance of dustfall during this event was 12.5–15.0gm−2, making up about 10% of the total annual dustfall in Beijing. Dustfall amounted to 205 thousand tons in Beijing, the largest amount observed in recent years. The dust particles were mostly angular, subangular and subrounded in morphology, and the MMD was nearly 12μm. Particles <10μm accounted for 54.7% by number, but fine sand particles (larger than 50μm) made up 53.7% by volume. Particles with diameters larger than 20μm made up of the predominant volume of the samples (90.35%). Hence, this dustfall event was characterized by a high content of fine sand and coarse silt particles. The principal elements in the dust particles were C, O, Si, Al, Fe, and Ca, whereas the major minerals were quartz, Na-feldspar, calcite, and clay minerals. [ABSTRACT FROM AUTHOR]

Abstract: The focus of the current study is on a state-of-the-art twin-layer gas diffusion layer (GDL) which consists of carbon tissues with a fibre diameter of 5–20μm, and contains a microporous layer (MPL) coating which has sub-micron porous features. In the current study, real-world digital three-dimensional images of the GDL-MPL assembly are created through X-ray nano-tomography with a 680nm pixel resolution for the GDL and focused ion beam/scanning electron microscopy (FIB/SEM) nano-tomography with a 14nm pixel resolution for the MPL. The critical nano-structural features including porosity, characteristic lengths and 3D pore size distribution are determined directly from the 3D digital representation. In addition to morphological parameters, the FIB/SEM nano-tomography technique has been combined with lattice Boltzmann (LB) numerical modelling in order to calculate the tortuosity and permeability of the MPL. [Copyright &y& Elsevier]

Abstract: Morphological parameters of a 3D binary image of a porous carbon gas diffusion layer (GDL) for polymer electrolyte fuel cells (PEFC) reconstructed using X-ray nano-tomography scanning have been obtained, and influence of small alterations in the threshold value on the simulated flow properties of the reconstructed GDL has been determined. A range of threshold values with 0.4% increments on the greyscale map have been applied and the gas permeability of the binary images have been calculated using a single-phase lattice Botlzmann model (LBM), which is based on the treatment of nineteen velocities in the three dimensional domain (D3Q19). The porosity, degrees of anisotropy and the mean pore radius have been calculated directly from segmented voxel representation. A strong relationship between these parameters and threshold variation has been established. These findings suggest that threshold selection can significantly affect some of the flow properties and may strongly influence the computational simulation of micro and nano-scale flows in a porous structure. [Copyright &y& Elsevier]

This paper focuses on the study of the influence of the loading frequency on the fatigue life in compression of natural hydraulic lime (NHL) mortars. For this purpose, fatigue tests were performed under three different loading frequencies: 0.05 Hz, 0.5 Hz, and 5 Hz. The maximum and minimum stresses applied in the fatigue tests were 85% and 20% of the compressive strength of the mortar, respectively, and the runout limit was set at around three days. It is observed that the NHL mortar is sensitive to the loading frequency; that is, for higher frequencies, more cycles are resisted by the specimens. Concerning the secondary strain of the fatigue creep curves, the Sparks and Menzies law was satisfied independently of the loading frequency. This law is useful to predict the number of cycles to failure of runouts if the secondary strain is known. In addition, given the high scatter of results, a probabilistic treatment is applied. Firstly, they were fitted to a two-parameter cumulative Weibull distribution function. Secondly, the results were fitted to a probabilistic fatigue model based on the initial distribution. With it, one can obtain the failure probability of the material for any given value of loading frequency. Finally, we observed an increase in the residual strength after fatigue in comparison to the static compression tests of around 40%. Through mercury intrusion porosimetry tests, it is concluded that a possible chemical curing of the material could have occurred induced by the cyclic loads. • Effect of loading frequency on fatigue to study cyclic loads of various intensities. • NHL mortar sensitive to loading frequency; the higher it is, the more N. • The Sparks and Menzies law is satisfied independently of the loading frequency. • Adjustment to a 2-parameter Weibull distribution function and a probabilistic model. • 40% increase of the residual strength comparing to the static compressive one. [ABSTRACT FROM AUTHOR]

The size effect on the compressive fatigue behaviour of fibre-reinforced concrete is herein studied by testing cubes of 40 mm, 80 mm and 150 mm in edge length. Even though the compressive strength resulted the same in the three cases due to the ductility of the material in this range of sizes, the size effect was evident on the fatigue response of the 40-mm specimens, which reached numbers of cycles up to three orders of magnitude higher than expected. Furthermore, the mean residual strength of run-out specimens of this size increased by 42% due to the cyclic loads. Regarding the fatigue creep of the material, the logarithms of the secondary strain rate and the number of cycles to failure presented a linear relationship that is size-independent and can predict the fatigue life of run-out specimens. Meanwhile, the strain upon failure decreased with the increase of size although the crack patterns were still similar. • Increased fatigue life for smaller cubic specimen sizes of fibre-reinforced concrete. • Constant compressive strength under the size of 150 mm due to the effect of fibres. • Mean increment of a 42% in the post-fatigue compressive strength of run-out specimens. • Size-independent relationship between the secondary strain rate and fatigue life. • Decrease of fatigue failure strain for larger sizes. [ABSTRACT FROM AUTHOR]

Abstract: The mountain-based GPS radio occultation is a novel approach to lower atmospheric profiling. The experiments of the mountain-based GPS radio occultation were conducted on the top of Mt. Yaogu (29.38°N, 113.68°E, ∼1240m) on December 17, 2003, and on the top of Mt. Jiugong (29.39°N, 114.65°E, ∼1550m) on July 24, 2004. Based on these observation data, the scientific data processing software has been developed and is used to retrieve successfully the atmospheric refractivity profiles. The validation experiment was performed on the top of Mt. Wuling (40.60°N, 117.48°E, ∼2118m) during August 1–29, 2005. Collocated automatic weather station and the radiosondes nearby were operated simultaneously for the comparison campaign. Results show that the radio occultation technique obtained about 40 profiles every day with the receiver antenna pointing to the south. Comparisons show that the refractivity measured by occultation agree well with those by the radiosondes, but not well with those by the automatic weather station due to their much different geographic locations of measurements. Results of these experiments suggest that the mountain-based GPS radio occultation is an economic reliable novel technique monitoring temporal and spatial variations of local lower atmospheric environments. [Copyright &y& Elsevier]

Abstract: Large negative magnetoresistance (MR) has been observed in the broken cold-pressed CrO2 powder samples near the room temperature, which is ascribed to the magnetic field-induced mechanical contact variation. This large, room-temperature negative MR might easily lead to a wrong conclusion that the spin-polarization is still very high at high temperatures. This observation may also point to the possibility to develop field sensors based on the mechanical MR. [Copyright &y& Elsevier]

Abstract: Olivine-type LiFePO4 has been a promising electrode material for lithium ion battery, but the poor conductivity limits its practical application. In order to improve the electronic conductivity, a small amount of ion (Mg2+, Cu2+ and Zn2+) was added by the route of co-precipitation. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) along with energy dispersive spectroscopy (EDS), and their electrochemical properties were investigated by cyclic voltammetry (CV) and galvanostatic charge and discharge tests. The results indicate that these ion dopants do not affect the structure of the material but considerably improves its capacity delivery and cycle performance, which is ascribed to the enhancement of the electronic inductivity by ion doping. Co-precipitation doping is an effective method to improve the ion doping results. [Copyright &y& Elsevier]

Abstract: Single-crystalline Se nanowire arrays have been fabricated by electrodeposition using anodic porous alumina templates. The microstructures of Se nanowires were sensitive to the deposition condition. The nanochannels in the template not only determined the morphology of Se nanowires but also influenced their microstructures. We found Se nanowires deposited at 40°C were an uncommon Se face-centered cubic structure, which was determined to be CaF2 type. The phase transformation in Se nanowires has been studied by Raman spectroscopy and transmission electron microscopy. [Copyright &y& Elsevier]

Co nanoparticle films were prepared by plasma–gas-condensation-type particle beam deposition system. High-resolution transmission electron microscopy images show that the Co nanoparticles have a very narrow size distribution with an average diameter of ∼20 nm, and each of the Co nanoparticles is covered with an ∼3 nm layer of CoO. Hysteresis loops of the films after field-cooling in a 5 T magnetic field are greatly shifted, which can be attributed to the exchange bias effect caused by the interfacial exchange coupling between the CoO shell and the Co core. The zero field cooled films show several prominent properties, such as a quite large coercive field, a small remanence and their abnormal dependences on temperature. All these observations can be attributed to the existence of an exchange bias effect within each single Co nanoparticle even without a field-cooling process. [Copyright &y& Elsevier]

TMx–(SiO2)1−x (TM=Fe, Co, Ni) thin films were prepared in a wide concentration range (0.35 &les;x&les;1). Structure was studied with transmission electron microscopy (TEM), X-ray diffraction (XRD) and small angle X-ray scattering (SAXS). Magnetic and magnetotransport properties were investigated by means of magnetization and Hall effect measurements. TEM images display nanometric spherical structures embedded in a SiO2 amorphous matrix, with typical sizes increasing from 3 to 5 nm when TM volume concentration x is increased. SAXS measurements indicate a complex structure formed by nanosized objects. XRD measurements show that the structure is composed by amorphous SiO2 and TM crystallites. Slightly above the percolation threshold all samples display giant Hall effect. The observed magnetic properties are dependent on x, and display an evolution resulting from the progressive increase of the mean particle size. [Copyright &y& Elsevier]

A one-dimensional multi-layer model is presented to characterise the skin burn process resulting from the application of a high temperature heat source to a skin surface. Transient temperatures were numerically calculated using a finite difference method to solve the Pennes bioheat equation. A damage function denoting the extent of burn injury was then calculated using the Arrhenius assumptions. The model was used to predict the effects of thermal physical properties and geometrical dimensions on the transient temperature and damage function distributions. The results show that the epidermis and dermis thicknesses significantly affect the temperature and burn injury distributions, while variations of the initial temperatures and the blood perfusion have little effect. [Copyright &y& Elsevier]

The relationship between nanostructure, exchange coupling and magnetic properties of Nd2(Fe, Co, Mo)14B/α-Fe nanocomposite magnets prepared by mechanical alloying (MA) has been studied systematically. Different categories of grain interfaces have been directly observed, which correspond to different types of exchange couplings in the Nd2Fe14B/α-Fe-type nanocomposite magnets. The notable decrease of the spin-reorientation temperature Tsr of Nd2Fe14B phase convincingly demonstrates the presence of strong inter-grain exchange coupling in the Nd2Fe14B/α-Fe-type nanocomposites. For as-annealed Nd8.4Fe87.1−xMoxB4.5 (x=0, 0.6, 1.1 and 1.6) and Nd8.4Fe80.4Co5.6Mo1.1B4.5 alloys, the intrinsic coercivity μ0Hc and the maximum magnetic energy product (BH)max are remarkably improved in the alloys with only Mo-additions as well as in the Nd8.4Fe80.4Co5.6Mo1.1B4.5 alloy. The improvement of the magnetic properties is the result of an enhancement of the exchange coupling, because of the modifications of nanostructural factors and phase components by a proper substitution of 3d elements for Fe. [Copyright &y& Elsevier]

Discusses 4 angstrom tubes' exhibition of superconducting behavior manifest as an anisotropic Meissner effect. Superconducting gap and fluctuation supercurrent; Magnetic and transport properties of single-walled small-diameter carbon nanotubes embedded in a zeolite matrix; Smooth temperature variations owing to one-dimensional fluctuations.

The objective of this study was to determine the seroprevalence, risk factors and genotypes of Toxoplasma gondii in white yaks ( Bos grunniens ) in China. A total of 974 serum samples were collected from white yaks in Tianzhu Tibetan Autonomous County (TTAC), Gansu province, northwest China for detecting T. gondii antibodies by the modified agglutination test (MAT), and 414 tissues belonging to 138 white yaks were collected for detecting T. gondii DNA by amplification of B1 gene with a semi-nested PCR. A total of 155 serum samples (15.91%) were seropositive for T. gondii antibodies at a 1:100 cut-off, and 10 DNA samples (7.25%) were positive for the T. gondii B1 gene, which were genetically characterized using multilocus PCR-RFLP. Only one genotype (ToxoDB#9) was identified from two samples with complete genotyping results. Statistically significant differences were not observed between T. gondii seroprevalence and gender, season or pregnancy in the logistic regression analysis ( P > 0.05). Ages of white yaks was considered as a main risk factor associated with T. gondii infection. Our results indicated a widespread exposure to T. gondii among white yaks, and revealed the genotype ToxoDB#9 of T. gondii in white yaks for the first time in China. [ABSTRACT FROM AUTHOR]

The growth of trace amount of niobium (Nb) doped β -Ga 2 O 3 thin films have been demonstrated on (0001) sapphire substrates by radio frequency magnetron co-sputtering method. The crystallization, morphology and optical properties of Nb doped β -Ga 2 O 3 films have been investigated. The deep ultraviolet (DUV) photodetector with a metal–semiconductor–metal structure based on trace amount of Nb doped β -Ga 2 O 3 thin film was fabricated. The DUV photodetector exhibits high photo-to-dark-current ratio and fast photo-response speed, suggesting the performance of β -Ga 2 O 3 photodetector can be improved by doping trace amount of Nb in β -Ga 2 O 3 thin film. [ABSTRACT FROM AUTHOR]

Abstract: The coefficient of thermal expansion (CTE) of aluminum matrix composite reinforced with 1.0wt.% multi-wall carbon nanotubes (MWNTs) fabricated by cold isostatic pressing and hot squeeze technique was measured between 25 and 400 °C with a high-precision thermomechanical analyzer, and compared with those of pure aluminum and 2024Al matrix fabricated under the same processing. The results show that the CTE of the composite obviously reduces in relation to those of pure aluminum and 2024Al matrix due to the introduction of MWNTs. The addition of 1.0wt.% MWNTs to 2024Al matrix decreases the CTE by as much as 12% and 11% compared with those of pure aluminum and 2024Al matrix at 50 °C, respectively, which indicates that carbon nanotube reinforced metal matrix composite may be a promising materials with low CTE. [Copyright &y& Elsevier]