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A detailed structural, magnetic, and ferroelectric property of bulk polycrystalline Y1-xZrxCrO3 (0 ≤ x ≤ 0.2) has been made. All the samples in the present series were made using the standard solid-state sintering technique. X-ray diffraction (XRD) data reveals that the single-phase samples can be prepared for Zr-concentration up to x = 0.1, and a systematic decrease of the lattice parameters can be observed with the increase of Zr doping at the Y-site in the present YCrO3 system. All the samples show paramagnetic to antiferromagnetic transition around 140 K (TN) as revealed from the temperature-dependent magnetization (M) data, and a small increase in the value of saturation magnetization (Msat) can be seen with successive Zr-doping in the system. Interestingly, unlike YCrO3, the M-T data measured under the zero-field cooled (ZFC) condition shows negative M value for both the Zr-doped samples in the present series below TN. A notable enhancement of both critical field (HC) and remnant magnetization (Mr) is observed for the Zr-doped samples compared with the pristine YCrO3 sample measured under similar conditions. Polarization-electric field (P-E) hysteresis behavior of undoped and Zr-doped samples is measured at low temperature to reduce leakage current contribution, show an enhancement of remnant polarization (Pr) with successive Zr doping within YCrO3, indicating a better bifferoic nature in Zr-doped sample in the present study. [ABSTRACT FROM AUTHOR]

Study design:A prospective study.Objectives:To evaluate the effect of the surgery to reconstruct thoracic breathing in patients with high cervical spinal cord injury (CSCI).Setting:China Rehabilitation Research Center, Beijing, China.Methods:The posterior ribs (from the fifth to the eighth) were suspended on the inferior angle of the scapula on each side using titanium cables, as well as muscles and myofascial tissue in the subscapular area. After the surgery, the patients were trained for synchronous contraction of the trapezius and diaphragm muscles, and electromyography (EMG) was performed to evaluate the synchronization. The clinical symptoms and pulmonary function were assessed within 1 week before surgery and at 2, 12 and 24 postoperative weeks.Results:Six patients with complete high CSCI received rib suspension surgery 84±26.7 days after spinal cord injury. Before the surgery, all of the patients presented with weakened cough, retention of respiratory secretions and dyspnea, while these symptoms alleviated postoperatively. The vital capacity (VC) was enhanced to be 1680±282 ml at 2 weeks after the surgery, compared with 1085±92 ml (P=0.013). The EMG showed a synchronous muscle electrical activity between the trapezius muscles and diaphragm during deep breaths.Conclusion:The rib suspension surgery partially restored the thoracic breathing of the patients with high CSCI, thereby improving VC, cough and expectoration. [ABSTRACT FROM AUTHOR]

We performed high-field magnetization measurements, M( H), on the Ni5(TeO3)4Br2 by using a pulse magnet. The Ni2+ ions ( S = 1) of this compound form a two dimensional distorted spin frustrated system (distorted kagome lattice), and undergo a Neel transition at T N∼29 K, due to the anisotropy. Below T N, a complex spin arrangement which contains ten spin sub-lattices was suggested by neutron scattering and electron spin resonance studies. We observed a step-like transition at H c∼11 T when T< T N. By contrast, at T> T N, the field-dependent magnetization curves behaved like a straight line. The H c is close to those obtained by previous spin resonance studies of Ni5(TeO3)4Br2 and Ni5(TeO3)4Cl2 in which a spin-flop-like transition was proposed to explain the field-dependent resonance spectra. Interestingly, the observed change in magnetization (Δ M) at H c corresponds to nearly one-half of the magnetic moment of Ni2+ ion, suggesting that the observed step-like behavior possibly corresponds to a spin-flip-like transition (i.e. from antiferromagnetic state to ferrimagnetic state). In addition, in the high-field region ( H> H c), the M( H) curves did not show plateau behavior, but exhibited the straight lines having finite slopes without any sign of saturation up to 55 T. [ABSTRACT FROM AUTHOR]

This paper describes the optical characteristics of indium- and tungsten-doped ZnGa2O4 phosphor for field emission display (FED). The solid-state reaction is used to synthesize the phosphor powder, and the phosphor film is prepared by electrophoresis. Indium doping enhances the luminescence of ZnGa2O4 phosphor; nevertheless, the emission of phosphor doped by tungsten shifts to the short wavelength region. From the measurement of the cathodoluminescence (CL), it reveals that the luminescence of the phosphor film is improved when it is annealed in an O2/Ar atmosphere. A luminance of 2,080 cd/m&2 is obtained as the phosphor film is excited at an electron voltage of 5 kV and an anode current of 30 µA. [ABSTRACT FROM AUTHOR]

Polycrystalline (Cu1−xZnx)2OSeO3 (0 ≤ x ≤ 0.2) samples were synthesized using solid-state reaction and characterized by X-ray diffraction (XRD). The effect of Zn doping upon saturation magnetization (MS) indicates that the Zn favors to occupying Cu(II) square pyramidal crystallographic site. The AC susceptibility (χ′ac) was measured at various temperatures (χ′ac-T) and magnetic field strengths (χ′ac-H). The Zn doping concentration is found to affect greatly the M-T and χ′ac-T. The skyrmion phase has been inferred from the χ′ac-H data, and then indicated within the H-T phase diagrams for various Zn doping concentrations. The striking and unexpected observation is that the skyrmion phase region becomes split upon Zn doping concentration. Interestingly, second conical boundary accompanied by second skyrmion phase was also observed from dχ′ac/dH vs. H curves. Atomic site disorder created by the chemical doping modulates the delicate magnetic interactions via change in the Dzyaloshinskii-Moriya (DM) vector of distorted Cu(II) square pyramidal, thereby splitting of skyrmion phase might occur. These findings illustrate the potential of using chemical and atomic modification for tuning the temperature and field dependence of skyrmion phase of Cu2OSeO3. [ABSTRACT FROM AUTHOR]

We performed high-field magnetization measurements, M( H), on the Ni5(TeO3)4Br2 by using a pulse magnet. The Ni2+ ions ( S = 1) of this compound form a two dimensional distorted spin frustrated system (distorted kagome lattice), and undergo a Neel transition at T N∼29 K, due to the anisotropy. Below T N, a complex spin arrangement which contains ten spin sub-lattices was suggested by neutron scattering and electron spin resonance studies. We observed a step-like transition at H c∼11 T when T< T N. By contrast, at T> T N, the field-dependent magnetization curves behaved like a straight line. The H c is close to those obtained by previous spin resonance studies of Ni5(TeO3)4Br2 and Ni5(TeO3)4Cl2 in which a spin-flop-like transition was proposed to explain the field-dependent resonance spectra. Interestingly, the observed change in magnetization (Δ M) at H c corresponds to nearly one-half of the magnetic moment of Ni2+ ion, suggesting that the observed step-like behavior possibly corresponds to a spin-flip-like transition (i.e. from antiferromagnetic state to ferrimagnetic state). In addition, in the high-field region ( H> H c), the M( H) curves did not show plateau behavior, but exhibited the straight lines having finite slopes without any sign of saturation up to 55 T. [ABSTRACT FROM AUTHOR]

Polycrystalline (Cu1−xZnx)2OSeO3 (0 ≤ x ≤ 0.2) samples were synthesized using solid-state reaction and characterized by X-ray diffraction (XRD). The effect of Zn doping upon saturation magnetization (MS) indicates that the Zn favors to occupying Cu(II) square pyramidal crystallographic site. The AC susceptibility (χ′ac) was measured at various temperatures (χ′ac-T) and magnetic field strengths (χ′ac-H). The Zn doping concentration is found to affect greatly the M-T and χ′ac-T. The skyrmion phase has been inferred from the χ′ac-H data, and then indicated within the H-T phase diagrams for various Zn doping concentrations. The striking and unexpected observation is that the skyrmion phase region becomes split upon Zn doping concentration. Interestingly, second conical boundary accompanied by second skyrmion phase was also observed from dχ′ac/dH vs. H curves. Atomic site disorder created by the chemical doping modulates the delicate magnetic interactions via change in the Dzyaloshinskii-Moriya (DM) vector of distorted Cu(II) square pyramidal, thereby splitting of skyrmion phase might occur. These findings illustrate the potential of using chemical and atomic modification for tuning the temperature and field dependence of skyrmion phase of Cu2OSeO3. [ABSTRACT FROM AUTHOR]