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Chemical substitution is an effective method for tailoring the electrical and magnetic properties of functional materials. In this work, (1–x)Ba 0.1 Sr 0.9 TiO 3 - xBiFeO 3 (0.2  ≤ x  ≤ 0.8) ceramics were prepared by the modified Pechini method. X-ray diffraction patterns manifest that the samples undergo a gradual structural transformation from rhombohedral phase to tetragonal phase with increasing the content of Ba 0.1 Sr 0.9 TiO 3 (BST). Dielectric properties show that T C can be modulated by the doping level of BST in a wide range from 885 K to 260 K accompanied by the ferroelectric transformation from non-relaxor type to relaxor type ferroelectricity. The room temperature ferroelectricity, ferromagnetism and intrinsic magnetodielectric are observed in the BiFeO 3 -rich samples. Magnetization and magnetodielectric measurement both show that the spin cycloid is destroyed by the substitution of BST and the critical field for the transition from spiral to antiferromagnetic collinear magnetic structure decreases with increasing the amount of BST. These findings manifest that this materials are quite promising for potential applications in BFO-based magnetoelectric devices and electrocaloric cooling technologies. [ABSTRACT FROM AUTHOR]

[Display omitted] • The microstructure evolution of W after He2+ irradiation was assessed via synchrotron GIXRD and GISAXS. • Irradiation results in a lattice swelling which is more severe at higher irradiation temperature and fluence. • High density dislocation loops were formed after irradiation at room temperature. • High density He bubble were formed in the sample interior after irradiation at 400 °C. • Provide a reference for the study of ion irradiation damage via synchrotron GIXRD and GISAXS. In this study the microstructure evolution in sub-surface layer of the coarse-grained W after irradiation of 400 keV He2+ at different fluences and temperatures was assessed by synchrotron grazing incident X-ray diffraction (GIXRD) and grazing-incidence small-angle X-ray scattering (GISAXS). The splitting of GIXRD peaks obtained at different incident angles indicates that the un-irradiated coarse-grained W exhibits a compression strain state in the near surface and the He ions irradiation results in a lattice swelling which is more severe at higher irradiation temperature and fluence. The GISAXS results combined with the TEM analysis indicate that after irradiation at room temperature, uniformly distributed high density dislocation loops with an average radius of about 3.7 nm were formed due to the extrusion of He-V clusters. After irradiation at 400 °C, high density He bubbles with radii between 1 and 3 nm were formed in the sample interior, while large blisters appeared near the surface. This work provides a reference for the study of irradiation damage in the sub-surface layer of W alloys via synchrotron GIXRD and GISAXS. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we have succeeded in destabilizing LiBH4 by the addition of SrH2, via the reaction 6LiBH4 +SrH2 →SrB6 +6LiH+10H2 with a theoretical hydrogen capacity of 9.1wt.%. According to the van’t Hoff and Arrhenius equations, the dehydrogenation enthalpy change and activation energy for the LiBH4/SrH2 system were experimentally determined to be 48kJ/mol H2 and 64kJ/mol, respectively. Both are remarkably reduced in comparison with the pristine LiBH4, which is responsible for the improved dehydrogenation property of the LiBH4/SrH2 system. The dehydrogenated products SrB6 +6LiH can be rehydrogenated to form LiBH4 and LiSrH3 at 723K under an initial hydrogen pressure of 8.0MPa. [Copyright &y& Elsevier]

Abstract: A simulation study is carried out to elucidate the effects of dynamical scattering, electron beam convergence angle and detection noise on atomic resolution diffraction imaging of small particles and to develop effective reconstruction procedures. Au nanoclusters are used as model because of their strong scattering. The results show that the dynamical effects of electron diffraction place a limit on the size of Au nanoclusters that can be reconstructed from the diffraction intensities with sufficient accuracy. For smaller Au nanoclusters, the simulations show that diffraction patterns recorded under the experimental conditions can be reconstructed using a combination of phase retrieval algorithms. The use of a low-resolution image is shown to be effective for reconstructing diffraction patterns without the central beam. A new algorithm for estimating the object support is proposed. [Copyright &y& Elsevier]

A letter to the editor is presented regarding the use of transvaginal Doppler ultrasound analysis of urethral clear cell carcinoma.

Abstract: Growth of ultrathin pentacene films is investigated as a function of coverage by atomic force microscopy. Initially, pentacene grows as monolayer fractal islands and evolves into compact islands before coalescence. Stabilization factors, against diffusion-limited-aggregation in terms of interaction between islands and interlayer monomer transport, are proposed to explain the shape transition. Simulations based on a simple model of heterogeneous film growth are found to agree with experimental observations. The role of surface diffusion in island shape transition is revealed by a comparison between pentacene growth on the hydrogen terminated and oxidized Si substrates. [Copyright &y& Elsevier]

• He+ implantation behavior of tungsten was investigated using Synchrotron XRD. • Four differently strained zones were identified in the He+ implanted tungsten. • The compressed zone is owing to the surface polishing effect and formation of He-complexes. • The expanded zone was ascribed to the helium atoms entering into the tungsten lattice. • The transition zone is a result of competition between the expanding and compressing effects A clear understanding on the H/He plasma implantation behavior in the plasma facing materials is a key issue to manage the implanted H/He in a future nuclear fusion reactor. In this work, the microstructure evolution of pure tungsten after low-energy (100 eV) and high-fluence (1023~1024 /m2) helium ion implantation was investigated by the synchrotron grazing incidence X-ray diffraction (S-GIXRD) and nanoindentation. Benefiting from the depth dependence of S-GIXRD and nanoindentation, it was found that the unimplanted W surface layer was composed of two zones: the compressed zone with a thickness of ~56 ± 2 nm under the top surface, which was introduced by the mechanical polishing, and the unaffected matrix. The helium implanted W surface layer was composed of four zones along the direction from the top surface to deep depth: the compressed zone with a thickness of ~46 ± 10 nm, transition zone with a thickness of ~146 ± 14 nm, expanded zone, and the matrix. The compressed zone becomes thinner after He implantation possibly owing to the formation of He-complexes. The expanded zone resulted from the helium atoms entering into the tungsten lattice, while the transition zone is a result of competition between the expanding and compressing effects. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• Rotation speed and friction of side walls significantly affect granular segregation. • Where the maximum granular temperature occurs and where particles separate coincide. • Double segregation effect (DSE) is found at Froude number (Fr) close to 1. Size-induced granular segregation was performed systematically and experimentally in an almost fully filled double-walled rotating drum at 10 different rotation speeds and two different side wall types. The motion of the granular materials was recorded using a high-speed camera for image analysis of particle segregation development in the drum. With continual tracking of the particle movements, the velocity, fluctuations, and granular temperatures were measured. The experimental results indicate that both rotation speeds and friction coefficient of side walls significantly affect segregation phenomena in binary-size mixture granular flows. The results demonstrate similar situations to the Brazil-nut effect and its reverse in the radial direction at either high or a low rotational speed (where the Froude number (Fr) is far from 1). At these instances, the maximum granular temperature occurs near the side walls. Specifically, a double segregation effect (DSE) is found at Froude number (Fr) close to 1. These results can be used in many industrial processes, for example, size grading of materials, screening of impurities, and different structures of functionally graded materials. Moreover, the maximum granular temperature occurs in the middle of the ring space. It causes small particles to move toward both side walls as it pushes bigger particles to accumulate in the middle of the ring space of rotating drum. [ABSTRACT FROM AUTHOR]

The effects of Co doping on structural, dielectric, and magnetic properties of multiferroic 0.6BiFe 1- x Co x O 3 -0.4(Bi 0.5 K 0.5 )TiO 3 (0 ≤ x ≤ 0.2) ceramics have been investigated. The samples undergo a structural transition from pseudocubic to rhombohedral phase at x = 0.1. The maximum remnant polarization of 57.8 μC/cm 2 and remnant magnetization of 0.107 emu/g are observed in the x = 0.15 sample. The ferromagnetism is proposed to originate from the suppression of spiral spin structure with the canting of the antiferromagnetically ordered spins caused by the substitution of Co for Fe ions. Moreover, the magnetodielectric effect can be observed in the x = 0.15 sample. [ABSTRACT FROM AUTHOR]

The Isochronous Mass Spectrometry (IMS) is a powerful technique developed in heavy-ion storage rings for measuring masses of very short-lived exotic nuclei. The IMS is based on the isochronous setting of the ring. One of the main parameters of this setting is the transition energy γ t . It has been a challenge to determine the γ t and especially to monitor the variation of γ t during experiments. In this paper we introduce a method to measure the γ t online during IMS experiments by using the acquired experimental data. Furthermore, since the storage ring has (in our context) a relatively large momentum acceptance, the variation of the γ t across the ring acceptance is a source of systematic uncertainty of measured masses. With the installation of two time-of-flight (TOF) detectors, the velocity of each stored ion and its revolution time are simultaneously available for the analysis. These quantities enabled us to determine the γ t as a function of orbital length in the ring. The presented method is especially important for future IMS experiments planned at the new-generation storage ring facilities FAIR in Germany and HIAF in China. [ABSTRACT FROM AUTHOR]

New mass values measured with the TITAN MR-TOF-MS are reported for the short-lived isotopes 24−26Ne, produced at TRIUMF's ISAC facility using a uranium carbide target and cold FEBIAD ion source. A least-squares adjustment within the framework of the Atomic Mass Evaluation was performed and the improved precision of the new mass values is highlighted. The improved mass accuracy in this N = 14 mid-shell region can also point to the refinement in values of the charge radii. By reducing the mass uncertainty of isotopes, their contribution of the mass shift uncertainty in laser spectroscopy can be negated. The work is part of developments for reaching the N = 20 Island of Inversion, where high molecular contamination hinders mass measurements of the neon isotopes. [ABSTRACT FROM AUTHOR]

Using isochronous mass spectrometry at the experimental storage ring CSRe in Lanzhou, the masses of 82 Zr and 84 Nb were measured for the first time with an uncertainty of ∼10 keV, and the masses of 79 Y, 81 Zr, and 83 Nb were re-determined with a higher precision. The latter are significantly less bound than their literature values. Our new and accurate masses remove the irregularities of the mass surface in this region of the nuclear chart. Our results do not support the predicted island of pronounced low α separation energies for neutron-deficient Mo and Tc isotopes, making the formation of Zr–Nb cycle in the rp -process unlikely. The new proton separation energy of 83 Nb was determined to be 490(400) keV smaller than that in the Atomic Mass Evaluation 2012. This partly removes the overproduction of the p -nucleus 84 Sr relative to the neutron-deficient molybdenum isotopes in the previous νp -process simulations. [ABSTRACT FROM AUTHOR]

We investigate the structural, magnetic, ferroelectric, and dielectric properties of Bi 6 Fe 2− x Ni x Ti 3 O 18 (0≤ x ≤1). The coexistence of ferroelectricity and ferromagnetism were observed at room temperature for the Ni-doped samples. The ferromagnetism in Bi 6 Fe 2− x Ni x Ti 3 O 18 can be understood in terms of spin canting of the antiferromagnetic coupling of the Fe-based and Ni-based sublattices via Dzyaloshinsky-Moriya interaction. Moreover, the substitution of Ni for Fe was effective for the enhancement of ferroelectric properties. The x =0.6 sample exhibits a maximum remnant polarization P r of 37.8 μC/cm 2 because of a lower leakage current. The rather large activation energy in the x =0 and 0.2 samples implies that the relaxation process may be not associated with the thermal motion of oxygen vacancies inside the bulk. [ABSTRACT FROM AUTHOR]

Hydrogenated diamond-like carbon (DLC) films or DLC films with hydrogenated interlayers tend to undergo early stage failure in water environments for reasons that are not fully understood. In this paper, a hydrogenated interface was prepared between a hydrogen free DLC film and a CoCrMo substrate, and the effects of the hydrogenated interface on the film structure, hardness, adhesion, wear behavior and corrosion resistance were investigated. The hydrogen free DLC films on the hydrogenated and the hydrogen free substrates exhibited similar structures and mechanical properties. The DLC films on both the hydrogenated and the virgin CoCrMo substrates exhibited good adhesion. The adhesions of the DLC films on both the substrates were not deteriorated after 150 days of immersion in 0.9% NaCl solution. The wear resistance of the DLC film on the hydrogenated CoCrMo substrate was worse than that on the virgin CoCrMo substrate in water. The presence of hydrogen improved the activity of the interface, restrained the formation of a passivation layer, and promoted the corrosion of the interface, which caused early stage failure of the DLC film in water. Therefore, the hydrogenated interface has a negative effect on the wear behaviors of DLC films in water environments. [ABSTRACT FROM AUTHOR]

Isochronous mass spectrometry (IMS) in storage rings is a powerful tool for mass measurements of exotic nuclei with very short half-lives down to several tens of microseconds, using a multicomponent secondary beam separated in-flight without cooling. However, the inevitable momentum spread of secondary ions limits the precision of nuclear masses determined by using IMS. Therefore, the momentum measurement in addition to the revolution period of stored ions is crucial to reduce the influence of the momentum spread on the standard deviation of the revolution period, which would lead to a much improved mass resolving power of IMS. One of the proposals to upgrade IMS is that the velocity of secondary ions could be directly measured by using two time-of-flight (double TOF) detectors installed in a straight section of a storage ring. In this paper, we outline the principle of IMS with double TOF detectors and the method to correct the momentum spread of stored ions. [ABSTRACT FROM AUTHOR]

The 2D distinct element method was used to investigate the propagation of fault rupture traces through overlying sand during reverse faulting along a range of dip angles and at different vertical throws. Calibrated micromechanical material parameters were used in the numerical simulations, which were validated through a comparison of the simulation results with those obtained from a centrifuge experiment involving acceleration at 80 g . The Gompertz sigmoid function with three parameters provided the best fit to the normalized surface deformation profiles obtained both from the numerical simulation and from centrifuge experiments. The three parameters that characterized the Gompertz sigmoid function were the normalized scarp height, the maximum slope on the scarp, and the location of the reverse fault outcropping. A surface deformation profile slope of 1/150 was used as the setback criterion. The normalized affected width and fault outcrop relative to the fault tip were determined for reverse faults having a variety of dips and throws. The dip angle significantly affected the kinematic mechanism underlying reverse faulting. At a given vertical throw, the scarp height increased as the dip angle decreased in the cases of α < 45°, and the scarp maintained a relatively constant height in the cases of α > 45°. As the dip angle decreased, the location of the fault outcropping shifted toward the footwall and the maximum slope on the scarp increased. The horizontal displacement played a significant role at low dip thrusts (α = 22.5°, 30°, 37.5°), a back-thrust fault developed, and an inverted triangle wedge formed in the subsurface. [ABSTRACT FROM AUTHOR]

Abstract: In isochronous mass spectrometry (IMS) established in heavy-ion storage rings the revolution times of the stored secondary ions should be independent of their velocity spread. However, this isochronous condition is fulfilled only in first order and in a small range of revolution times. To correct for the non-isochronicity an additional measure of the velocity or magnetic rigidity of each stored ion is required. For this purpose two new time-of-flight (TOF) detectors were installed in a straight section of the experimental Cooler Storage Ring CSRe in Lanzhou. The performance of the new time-of-flight (TOF) detectors, which is crucial for the achievable efficiencies and mass resolving power, was significantly improved. The time resolution of the TOF detector in offline tests was . The detector setup was put into operation with a stable beam of 78Kr. [Copyright &y& Elsevier]

Abstract: Accuracy of nuclear mass measurements in storage rings depends critically on the accuracy with which the revolution times of stored ions can be obtained. In such experiments, micro-channel plates (MCP) are used as timing detectors. Due to large phase space of injected secondary beams, a large number of ions cannot be stored in the ring and is lost within the first few revolutions. However, these ions interact with the detector and can saturate the MCP and thus deteriorate its performance. In order to eliminate such effects, a fast, pulsed high-voltage power supply (PHVPS) has been employed which keeps the detector switched-off during the first few revolutions. The new detector setup was taken into operation at the Experimental Cooler-Storage-Ring CSRe in Lanzhou and resulted in a significant improvement of the detector amplitude and efficiency characteristics. [Copyright &y& Elsevier]

Highlights: [•] Slice storage mechanism on MDSplus has been adopted for the effective solutions to the continuous and quasi real-time data storage. [•] Using circular linked list method solves the speed mismatch between the network transmission and the MDSplus writing. [•] Using LVS (Linux Virtual server) load balance technology, the new system provides a safe, highly scalable and highly available network service for user to access data. [ABSTRACT FROM AUTHOR]

Abstract: We investigate the north–south (N–S) asynchrony of the polar faculae and compare it with the hemispheric asynchrony of solar activity at low latitudes. We find that, (1) both the solar activity at high and low latitudes do not synchronously occur in the northern and southern hemispheres, there is phase shifts between the two hemispheres; (2) the N–S asynchrony of the polar faculae is a function of latitudes, implying that the asynchrony of the polar faculae between the two hemispheres is related to the hemispheric asymmetry and latitudinal distribution of the polar faculae. [Copyright &y& Elsevier]

Abstract: Anisotropic SmCo5 nanoflakes prepared by high-energy ball-milling with surfactants have great potential in applications for high-performance nanocomposite magnets. For such “nanocomposite” applications, the surface structure and chemistry of nanoflakes are crucial for achieving high coercivity. In this study, hot-pressed samples from anisotropic SmCo5 nanoflakes, ball-milled with different surfactants, oleic acid (OA) and oleylamine (OY), were investigated. Interface layers between the SmCo5 nanoflakes were found to consist of samarium oxides and a soft magnetic Co phase. These surface layers contribute to the degradation of hard magnetic performance, which is confirmed by scanning transmission electron microscopy-energy dispersive X-ray spectroscopy analysis of the cross-section of a single flake ball-milled with OA. Samples milled with OY show a much thinner interface layer in compacted samples, which means that the surface degradation during ball-milling with OY is much less than that with OA. The results show clearly that the choice of proper surfactant and the control of processing parameters are the key factors for improving the surface condition of the nanoflakes and the resulting hard magnetic properties. [Copyright &y& Elsevier]

Abstract: The in vitro degradation behaviour of Mg–Ca alloy was studied in the presence of albumin by in-situ observation, hydrogen evolution method and various electrochemical techniques. The corrosion and hydrogen evolution rates decreased and the formation of filiform corrosion induced by Cl− was also significantly inhibited due to the adsorption of albumin molecule. Moreover, the higher the concentration of albumin, the higher is the inhibitive effect. The EIS results further show that addition of albumin enhanced the charge transfer resistance and film resistance at the open-circuit potential. The synergistic effect of the negatively charged adsorbed albumin molecule and OH− has been discussed. [ABSTRACT FROM AUTHOR]

The applicability of the hyperspectral data from the canopy to the prediction of wheat grain quality was assessed for winter wheat. A training experiment and a validation experiment with contrasting nitrogen (N) levels and different cultivars were conducted, respectively, at different locations in Beijing, China. The wheat canopy spectral reflectance over 350–2500 nm, leaf N concentration and chlorophyll (Chl) concentration were measured at different growth stages, and the grain protein content was also determined after harvest. Eight vegetation indices (VIs) were compared relating to leaf N concentration, and the result indicated that the plant pigment ratio (PPR, (R550-R450)/(R550+R450)), a Chl-based index, was most applicable to predict wheat grain protein due to its significant correlation with leaf N concentration at the post-anthesis stage. Based on the relationships among PPR, leaf Chl concentration, leaf N concentration, and grain protein content, the statistical prediction models of grain protein content for Zhongyou9507 (a hard winter wheat) and Jingdong8 (a semi-hard winter wheat) were developed. The root mean square error (RMSE) of the 18 DAA (days after anthesis) model of Zhongyou9507 was 0.175; those of the anthesis model and the 11 DAA model of Jingdong8 were 0.238 and 0.982, respectively. Taking both the precision and accuracy into account, the 18 DAA model of Zhongyou9507 and the anthesis model of Jingdong8 were recommended to predict grain protein content for each cultivar. The result demonstrated that PPR could be used to assess grain quality of winter wheat. [Copyright &y& Elsevier]

Mass measurements of 49,50Sc, 70As, 73Br and 196Hg nuclides produced at CERN's radioactive-ion beam facility ISOLDE are presented. The measurements were performed at the ISOLTRAP mass spectrometer by use of the multi-reflection time-of-flight and the Penning-trap mass spectrometry techniques. The new results agree well with previously known literature values. The mass accuracy for all cases has been improved. [ABSTRACT FROM AUTHOR]