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We study the effects of GaN interlayer on the transport properties of two-dimensional electron gases confined in lattice-matched AlInN/AlN/GaN heterostructures. It is found that the Hall mobility is evidently enhanced when an additional ultrathin GaN interlayer is introduced between AlInN and AlN layers. The enhancement of the Hall mobility is especially remarkable at low temperature. The high Hall mobility results in a low sheet resistance of 23Ω=⧠ at 2K. Meanwhile, Shubnikov-de Haas oscillations (SdH) are also remarkably enhanced due to the existence of GaN interlayer. The enhancement of the SdH oscillations is related to the larger quantum mobility μq owing to the suppression of the interface roughness, alloy disorder, and ionized impurity scatterings by the GaN interlayer. [ABSTRACT FROM AUTHOR]

The hollow spherical nano-TiO2 was successfully synthesized by carbon spheres as the template and Ti-bearing blast furnace slag as the Ti source. The SEM and TEM results showed that the as-synthesized TiO2 consist of uniform separated hollow spheres, and the sphere wall was composed of nanoparticles. The XRD result showed that the crystallized phase was rutile. Almost complete extraction of Ti from slag was achieved in NaOH-NaF molten salt. The kinetic analysis indicated that the slag decomposition was applied to control of chemical reaction of the reactionless core-shrinking model, and the apparent activation energy was39.54 kJ mol-1. [ABSTRACT FROM AUTHOR]

In this study, the polymorphism of ANGPTL4 and POMCgene in 92 individuals of Guanling cattle was detected using DNA sequencing technology and the correlation between polymorphic loci and growth traits of Guanling cattle was analyzed. Three mutation sites including 387 C > T, 418 C > T and 449 A > T were detected in ANGPTL4 gene. Five mutation sites including 138 C > T, 430 C > T, 644 C > T, 668C > T and 693A >G were detected in POMC gene. The results showed that three polymorphic mutation sites of ANGPTL4 gene in the Hardy - Weinberg disequilibrium (HWE) (P < 0.05), POMC gene in 430 C > T mutation the mutation in HWE equilibrium (P > 0.05), multi peptide information content of ANGPTL4, POMC gene polymorphisms (PIC) showed moderate polymorphism. The correlation analysis results showed that the ANGPTL4 gene 418 C > T mutation genotypes and Guanling yellow body height, body length, chest circumference, abdominal circumference showed significant differences (P < 0.01), 449 A>T mutation genotypes and Guanling yellow body height showed a significant difference (P < 0.05) and chest circumference, abdominal circumference showed significant differences (P < 0.01). POMC gene 644 C > T and 668C > T mutation loci and body length of Guanling yellow cattle showed significant difference (P < 0.05). [ABSTRACT FROM AUTHOR]

The effective masses for spin-up and spin-down electrons of a partially spin-polarized Fermi liquid are theoretically expected to be different. We extract the spin-up and spin-down effective masses from magnetotransport measurements at different temperatures for a two-dimensional electron gas in an In0.65Ga0.35As/In0.52Al0.48As quantum well exhibiting zero-field spin splitting. We apply two analytical methods, one involving the simultaneous fitting of fast Fourier transform (FFT) spectra and the other involving inverse FFT analysis. Both methods confirm that the effective masses for spin-up and spin-down are different, consistent with theoretical expectations. [ABSTRACT FROM AUTHOR]

We have investigated spin-related oscillatory magnetoresistances of the two-dimensional electron gas in the inversion layer on bulk p-Hg1-xCdxTe at low temperatures. The oscillatory magnetoresistances are found to display beating pattern at low magnetic fields and to exhibit spin-splitting structure at high magnetic fields. We attribute the beating pattern to zero-field spin splitting due to spin-orbit coupling by analyzing fast-Fourier-transform results and Hall resistance. By modulating the oscillatory magnetoresistances we investigate the influence of spin-orbit coupling, Zeeman splitting, and the second populated subband on the appearance of beating patterns and the spin-splitting structure in oscillatory magnetoresistances. The strong spin-orbit coupling and the large effective g factor are demonstrated to be the significant parameters in controlling the appearance of spin-related oscillatory magnetoresistance in the inversion layer on bulk p-Hg1-xCdxTe. A good agreement between magnetoresistance data and theory suggests a spin-orbit coupling parameter α = 2.8 × 10-11 eV•m and the effective g factor g* = -44.0. The spin-orbit coupling effect presented in the inversion layer on bulk p-Hg1-xCdxTe provides a potential candidate for spintronic devices. [ABSTRACT FROM AUTHOR]

We study the insulator-quantum Hall conductor transition in two high-density gated InGaAs/InAlAs quantum well samples. We observe a well-defined critical magnetic field and verify this marks a genuine phase transition by investigating the scaling behavior of the longitudinal resistivity with field and temperature at fixed electron density. Consistent with prevailing experimental results the critical field decreases with increasing electron density in one sample (QW0710). In the other sample (QW0715), with higher delta doping density, however, we unexpectedly find that the critical field increases with increasing electron density. This unexpected behavior may be the result of the system entering the classical percolation regime. [ABSTRACT FROM AUTHOR]

We report on the strong spin-orbit (SO) interaction in a gated high-mobility In0.53Ga0.47As/InP quantum well two-dimensional electron gas. We establish that the SO interaction is dominated by the Rashba mechanism. The Rashba coupling parameters determined from analysis of both weak antilocalization and the beating pattern in the Shubnikov–de Haas oscillations are in reasonable agreement, and the small difference between them was explained by a magnetic-field-dependent effective g factor. The zero-field spin splitting shows nonmonotonic behavior with a maximum as the electron density is varied with the applied gate voltage. This is related to strong Rashba SO coupling in our sample. [ABSTRACT FROM AUTHOR]

We study the magnetotransport properties of a gated In0.53Ga0.47As/InP quantum well structure in the presence of spin splitting when only one electronic subband is occupied. We develop an analytical method to extract the quantum mobilities for the two spin subbands. Ionized impurity scattering and alloy disorder scattering are determined to be important in this system. Larger quantum mobility is found for the higher-energy spin subband. We also demonstrate that the difference between the quantum mobilities for the two spin subbands can be altered with the gate. [ABSTRACT FROM AUTHOR]

We report on the magnetotransport properties of 100 nm wide parabolic quantum wells and observe an enhancement of the Hall resistance in one sample but not the other. This phenomenon is likely related to the effective thickness of the electronic slab. We also observe a parabolic negative magnetoresistance originating from electron-electron interactions when only one subband is occupied in one of the samples. The interaction correction to the Drude conductivity is extracted using two methods. We find that the extracted interaction correction increases with increasing tilted angle, for which two possible explanations are given. [ABSTRACT FROM AUTHOR]

The weak antilocalization (WAL) effects of the two-dimensional electron gas (2DEG) in high mobility AlxGa1-xN/GaN heterostructure as well as beating patterns in the Shubnikov–de Haas (SdH) oscillatory magnetoresistance have been investigated by means of magnetotransport measurements before and after illumination. The zero-field spin splitting mainly arising from the Rashba spin-orbit coupling effect is studied using the weak antilocalization and beating patterns analysis, respectively. The Rashba spin-orbit coupling constant α deduced using the weak antilocalization analysis showed a good agreement with that estimated from the analysis of the beating patterns for the sample before and after illumination. For our sample, the electron motion in the high mobility system is in the ballistic regime, the experimental WAL curves were fitted by a simulated quantum conductance correction according to a model proposed by [Golub [Phys. Rev. B 71, 235310 (2005)]. [ABSTRACT FROM AUTHOR]

Background: A combination of analgesic agents with different mechanisms can induce additive or synergistic analgesia. The N-type voltage-dependent calcium channel (N-VDCC) is a novel therapeutic target for pain control. In addition to providing effective pain relief when used alone, N-VDCC blockers produce synergistic analgesia when used in combination with opiates. However, the interaction between N-VDCC blockers and nonsteroidal anti-inflammatory drugs (NSAIDs) remains unclear.Methods: Using isobolographic analysis and composite additive curve analysis, the antinociceptive interaction between ZC88, a selective N-VDCC blocker and ibuprofen, a classical NSAID, was investigated in two mouse models of visceral and somatic inflammatory pain.Results: In the acetic acid writhing test, both ZC88 (10.5-42 mg/kg, intraperitoneally) and ibuprofen (50-200 mg/kg, orally) produced dose-dependent antinociception, with ED50 values of 27.2 and 100.5 mg/kg, respectively. ZC88 in combination with ibuprofen (ZC88 + ibuprofen) also induced significant antinociception, and isobolographic analysis revealed a synergistic interaction at 50% effect level. The experimental ED50 (ED50 mix ) of this combination (34.5 mg/kg) was significantly lower than the theoretical ED50 (ED50 add ; 63.8 mg/kg). Additionally, composite additive curve analysis displayed synergistic interaction at other effect levels. In the formalin test, ZC88 or ibuprofen alone significantly reduced late-phase rather than early-phase pain, with ED50 values of 31.3 and 123.9 mg/kg, respectively. Similarly, both isobolographic analysis and composite additive curve analysis revealed synergistic antinociception of ZC88 + ibuprofen (40.6 mg/kg of ED50 mix vs. 77.6 mg/kg of ED50 add ).Conclusion: ZC88 in combination with ibuprofen produces synergistic antinociception in mouse models of somatic and visceral inflammatory pain.Significance: Because ZC88 + ibuprofen achieves the same antinociceptive effect at lower doses, the use of this combination could result in fewer dose-related untoward effects. The potentiation of ZC88 on ibuprofen-induced antinociception indicates that N-VDCC blocker has potential benefit to treat severe inflammatory pain. [ABSTRACT FROM AUTHOR]

Uniform perovskite core–shell nanocubes NaMn1−xMgxF3@NaMgF3 and NaMn1−xMgxF3:Yb3+@NaMgF3:Yb3+ have been successfully synthesized via a facile one-pot co-precipitation method at room temperature. The core–shell structures were carefully characterized by powder X-ray diffraction, transmission electron microscopy, scanning transmission electron microscopy and energy-dispersive X-ray elemental mapping. It was found that the formation mechanisms of the novel core–shell structures consist of aggregation of precursor molecules/ions, multiple nucleation, surface re-crystallization and further phase transformation. In addition, the DFT calculations further showed that Mn2+ ions tend to aggregate in NaMgF3:Mn2+, which may be one of the important intrinsic factors for the formation of the unique NaMn1−xMgxF3@NaMgF3 structure in this case. Besides, the unique core–shell structures NaMn1−xMgxF3:Yb3+@NaMgF3:Yb3+ can obviously enhance the near-infrared upconversion luminescence of Mn2+, which may find high potential in multiple high-resolution imaging applications. [ABSTRACT FROM AUTHOR]

The oscillatory magnetoresistance of the two-dimensional electron gas (2DEG) in AlxGa1-xN/GaN heterostructures has been studied by means of magnetotransport measurements at low temperatures and high magnetic fields. The split peaks of the Shubnikov–de Haas oscillations are observed at high magnetic fields, which are attributed to the spin splitting of the 2DEG. It is found that the spin splitting energy becomes smaller with an increase in magnetic field, indicating that the Zeeman spin splitting is not dominant at measured magnetic field range. Within this magnetic field range, the zero-field spin splitting, as well as Zeeman spin splitting, affects the split peaks in the oscillatory magnetoresistance of the 2DEG in AlxGa1-xN/GaN heterostructures. [ABSTRACT FROM AUTHOR]