We report p-type LiyNi0.97−yMn0.03O thin films (LNMO) via a simple solution method on silicon substrates. Magnetization measurements reveal that room-temperature tunable ferromagnetism can be observed in these LNMO th...
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We report p-type LiyNi0.97−yMn0.03O thin films (LNMO) via a simple solution method on silicon substrates. Magnetization measurements reveal that room-temperature tunable ferromagnetism can be observed in these LNMO thin films. The Mn L2,3 x-ray absorption and core-level photoelectron spectra indicate that Mn consists of the Mn2+ and Mn3+ components. The O K-edge x-ray absorption spectroscopy reveals that the majority of holes introduced by the Li doping have mainly O 2p character, and the hole concentration can be enhanced by almost two orders of magnitude by the Li doping, which can tune magnetism and TC. This ferromagnetic behavior in these LNMO thin films may be ascribed to the effective carrier-induced ferromagnetism (p-d exchange interaction through the O 2p band).
Pb0.95Sr0.05[(Mn1/3Sb2/3) 0.06(Ni1/2W1/2)x(Zr 0.49Ti0.51)1-x-0.06]O3 (PMS-PNW-PZT) (x = 0.01∼0.04) were prepared by using traditional technique with solid reaction process. The effects of PNW contents and sintering t...
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Pb0.95Sr0.05[(Mn1/3Sb2/3) 0.06(Ni1/2W1/2)x(Zr 0.49Ti0.51)1-x-0.06]O3 (PMS-PNW-PZT) (x = 0.01∼0.04) were prepared by using traditional technique with solid reaction process. The effects of PNW contents and sintering temperatures on microstructure, dielectric and piezoelectric properties of PMS-PNW-PZT ceramics were investigated. When the amount of doping content was about 2 mol% and the sintering temperature was 1250°C, the optimum values of buck density, mechanical quality factor, dielectric loss, piezoelectric constant, dielectric constant, planar coupling coefficient were obtained as follows:ρ = 7.54 g/cm3, Qm = 2800, tanδ = 0.27%, d33 = 360pC/N, Ε3T3/Ε0 = 1990, kp = 0.63, which can meet the requirements of piezoelectric transformers.
Structure characterization and elastic properties of tetragonal phase of zirconia have been investigated by density functional theory (DFT). The XRD spectrums and vibration properties of Raman active modes of T-ZrO2 w...
Structure characterization and elastic properties of tetragonal phase of zirconia have been investigated by density functional theory (DFT). The XRD spectrums and vibration properties of Raman active modes of T-ZrO2 were calculated and the results were compared with references. The calculated results have showed researchers may distinguish cubic and tetragonal phases used XRD spectrums in the 2 range of 72.5°-75.5°, 122°-129° and 138°-148°. The calculated vibrated properties of Raman active modes as follows: the modes of Zr-O stretching are 262.6, 486.2, and 641.6 cm−1 the modes of Zr-O bending and O-O coupling are 344.4 and 606.9 cm−1 and the modes of Zr-O-Zr or O-Zr-O bending is 141.2 cm−1.
Morphotropic phase boundary (MPB) of (0.8-x)PMT-xPbTiO3(PT)-0. 2PbZrO3(PZ) ternary system (x = 0.4) was studied by X-ray diffraction (XRD). It shows that by comparing with 0.4PMT-0.2PZ-0.4PT sample, after doping with ...
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Morphotropic phase boundary (MPB) of (0.8-x)PMT-xPbTiO3(PT)-0. 2PbZrO3(PZ) ternary system (x = 0.4) was studied by X-ray diffraction (XRD). It shows that by comparing with 0.4PMT-0.2PZ-0.4PT sample, after doping with Ni, c/a remains almost same (about1.009), while both c and a decrease indicating that lattice shrinks. Content of the tetragonal phase TP% of Ni-doped samples increase up to 81.1% when the doping limit of the nickel is reached (y = 0.05), and the dielectric constant Ε was found to increase up to 4570 when y = 0.05 and the Curie temperatures of doping samples were found to decrease from 175°C to 157°C.
It is found that the mechanical properties of welded joints is mainly related to the welding heating input and complicated mutual effects in multi composition welding material. According to this principle, a soft sens...
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The thermal expansion behavior of semiconductor single-crystal nanowire arrays is of importance for their applications in electronic and optoelectronic nanodevices. We prepare hexagonal ZnS single-crystal nanowire arr...
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The thermal expansion behavior of semiconductor single-crystal nanowire arrays is of importance for their applications in electronic and optoelectronic nanodevices. We prepare hexagonal ZnS single-crystal nanowire arrays growing along the [110] direction via electrodeposition. The thermal expansion properties of the as-prepared ZnS nanowires have been studied by in situ x-ray diffraction method. The thermal expansion coefficient （TEC） of the ZnS nanowires decreases consistently from room temperature to 225℃ where it reaches a minimum value, and then increases rapidly. The average TEC in the studied temperature range is 4.74 × 10-6/℃, which is smaller than that of the conventional bulk counterpart.
The small punch creep (SP-C) test technique is a new method which is applied to evaluate the high temperature creep properties of materials by using miniature specimen. In the present paper, the Finite Element Method ...
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A new kind of reactive toughening agent, defined as liquid crystalline polyurethane (LCPB), having both flexible chain and rigid biphenyl mesogenic groups was synthesized by polyaddition of 2,4-toluenediisocyanate (TD...
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A new kind of reactive toughening agent, defined as liquid crystalline polyurethane (LCPB), having both flexible chain and rigid biphenyl mesogenic groups was synthesized by polyaddition of 2,4-toluenediisocyanate (TDI) with diethylene glycol and 4,4'-dihydroxybiphenyl in DMF. The structure and morphology of the LCPB were investigated systematically by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), wide angle X-ray diffractometry (WAXD) and polarizing optical microscopy (POM), respectively. The POM observation confirmed that the LCPB exhibited nematic texture and good mesophase stability. The LCPB was used to modify the epoxy resin as toughening agents. The mechanical properties, dynamic mechanical behaviour, fracture surface morphology and apparent activation energy (Ea) of the modified systems were systematically investigated. The experimental results revealed that the impact strength of the epoxy resin modified with LCPB reached the highest value of 47.21 kJ/m2, and it is 1.8 times higher than that of the unmodified system when the content of LCPB loading reached 5 wt%. In addition, the tensile strength and the fracture strength also enhanced with increasing concentration of LCPB. The DMA results showed that the storage modulus in rubbery state and glass transition temperature (Tg) of the modified systems were higher than those of the unmodified system, indicating that the motion of epoxy matrix chains was strongly restricted by the rigidity of mesogenic units, while the Ea at glassy relaxation process of modified system was about 100-120 kJ/mol higher than that of the unmodified system. The effects of reinforcement on mechanisms of the damaging process of the modified systems were investigated by scanning electron microscopy.
The polycrystalline In2O3 ceramics doped with cobalt were prepared through the spark plasma sintering (SPS) process. Both thermoelectric transport properties and microstructure of the ceramics were investigated. The C...
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