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921.
Lin-Yu Jia Pu-Jian Mao Ji-Rong Ren 《The European Physical Journal C - Particles and Fields》2011,71(1):1-4
Consistent supercurrent multiplets are naturally associated with linearized off-shell supergravity models. In S.M. Kuzenko, J. High Energy Phys. 1004, 022 (2010) we presented the hierarchy of such supercurrents which correspond to all the models for linearized 4D $\mathcal{N}=1$ supergravity classified a few years ago. Here we analyze the correspondence between the most general supercurrent given in S.M. Kuzenko, J. High Energy Phys. 1004, 022 (2010) and the one obtained eight years ago in M. Magro et al., Ann. Phys. 298, 123 (2002) using the superfield Noether procedure. We apply the Noether procedure to the general $\mathcal{N}=1$ supersymmetric nonlinear sigma-model and show that it naturally leads to the so-called $\mathcal{S}$ -multiplet, revitalized in Z. Komargodski, N. Seiberg, J. High Energy Phys. 1007, 017 (2010). 相似文献
922.
Lin Su Chao Wang Yong-hao Yu Yong-ying Ren Ke-liang Xie Guo-lin Wang 《BMC neuroscience》2011,12(1):120
Background
Chronic neuropathic pain is an intractable pain with few effective treatments. Moderate cold stimulation can relieve pain, and this may be a novel train of thought for exploring new methods of analgesia. Transient receptor potential melastatin 8 (TRPM8) ion channel has been proposed to be an important molecular sensor for cold. Here we investigate the role of TRPM8 in the mechanism of chronic neuropathic pain using a rat model of chronic constriction injury (CCI) to the sciatic nerve.Results
Mechanical allodynia, cold and thermal hyperalgesia of CCI rats began on the 4th day following surgery and maintained at the peak during the period from the 10th to 14th day after operation. The level of TRPM8 protein in L5 dorsal root ganglion (DRG) ipsilateral to nerve injury was significantly increased on the 4th day after CCI, and reached the peak on the 10th day, and remained elevated on the 14th day following CCI. This time course of the alteration of TRPM8 expression was consistent with that of CCI-induced hyperalgesic response of the operated hind paw. Besides, activation of cold receptor TRPM8 of CCI rats by intrathecal application of menthol resulted in the inhibition of mechanical allodynia and thermal hyperalgesia and the enhancement of cold hyperalgesia. In contrast, downregulation of TRPM8 protein in ipsilateral L5 DRG of CCI rats by intrathecal TRPM8 antisense oligonucleotide attenuated cold hyperalgesia, but it had no effect on CCI-induced mechanical allodynia and thermal hyperalgesia.Conclusions
TRPM8 may play different roles in mechanical allodynia, cold and thermal hyperalgesia that develop after nerve injury, and it is a very promising research direction for the development of new therapies for chronic neuroapthic pain.923.
An experimental and simulation investigation regarding the effect of various CRAMPS parameters (delays interleaved with the decoupling shape, z-rotation symmetry and offset frequency) on the DUMBO decoupling performance is presented using two model compounds, glycine and tyrosine·HCl. Although the conclusions of this work may be extended to the other homonuclear-decoupling schemes, this work focuses essentially on the effect of adding interleaved delays to DUMBO decoupling during the indirect dimension using different 2D pulse-scheme architectures. While the simulations revealed an increasing loss of the spectral resolution with longer delays (from 0 to 6 μs), the experimental 2D (1)H DUMBO NMR correlation spectra revealed that the inclusion of delays, during the indirect dimension, improves the (1)H resolution whether the z-rotation symmetry was used or not. The best experimental spectra are obtained when z-rotation symmetry and windows are combined. 相似文献
924.
A cathode material of an electrically conducting carbon–LiFePO4 nanocomposite is synthesized by wet ball milling and spray drying of precursor powders prior to a solid-state reaction. The
structural characterization shows that the composite is composed of LiFePO4 crystals and 4.8 wt.% amorphous carbon. Galvanostatic charge/discharge measurements indicate that the composite exhibits
a superior high energy and high cycling stability. This composite delivers a discharge capacity of 159.1 mAh g−1 at 0.1 C, 150.8 mAh g−1 at 1 C, and 140.1 mAh g−1 at 2 C rate. The capacity retention of 99% is achieved after 200 cycles at 2 C. The 18,650 cylindrical batteries are assembled
using the composite as cathode materials and demonstrate the capacity of 1,400 mAh and the capacity retention of 97% after
100 cycles at 1 C. These results reveal that the as-prepared LiFePO4–carbon composite is one of the promising cathode materials for high-performance, advanced lithium-ion batteries directed
to the hybrid electric vehicle and pure electric vehicle markets. 相似文献
925.
对我国华南地区六种棕榈藤的纤维和导管形态特征进行了观测,研究了应用近红外光谱分析技术预测棕榈藤纤维长度和导管长度的可行性.结果表明:六种棕榈藤的纤维平均长度在1229~1917μm,导管的平均长度在1035~2129μm;发现株榈藤纤维长度和导管长度模型的建立采用偏最小二乘法和完全交互验证法,在350~2454 nm谱... 相似文献
926.
采用克莱森缩合反应合成了一种新型的β-二酮化合物1-(4-氨基苯)-4,4,4-三氟丁烷-1,3-二酮(p-NBFA).以其为第一配体,邻菲咯啉(phen)为第二配体,合成出新型Eu(Ⅲ),Tb(Ⅲ)三元配合物.通过元素分析确定了配合物的组成为Eu(p-NBFA)3phen和Tb(p-NBFA)3phen.红外光谱的分... 相似文献
927.
Fourier transform infrared spectroscopy(FTIR) and circular dichroism(CD) were used to investigate the conformational changes of heated whey protein(WP) and the corresponding changes in the hydrolysates immunoreactivity were determined by competitive enzyme-linked immunosorbent assay(ELISA).Results showed that the contents of α-helix and β-sheet of WP did not decrease much under mild heating conditions and the antigenicity was relatively high;when the heating intensity increased(70 ℃ for 25 min or 75 ℃ for 2... 相似文献
928.
铕与4-(4-吡啶甲酰基)苯甲酸配合物的合成与荧光性能研究 总被引:2,自引:0,他引:2
以Eu3+为中心离子,4-(4-吡啶甲酰基)苯甲酸(HPFBA)、1,10-菲罗啉(Phen)和三苯基氧膦(TPPO)为配体,合成了新型配合物Eu(PFBA)3(H2O)4,Eu(PFBA)3Phen(H2O)3和Eu(PFBA)3TPPO(H2O)3(PFBA=4-(4-吡啶甲酰基)苯甲酸根).红外光谱表明,形成配合... 相似文献
929.
高分辨连续光源石墨炉原子吸收光谱法测定面制食品中的铝 总被引:3,自引:0,他引:3
使用微波消解-高分辨连续光源石墨炉原子吸收光谱法测定四种面制食品(挂面、饺子皮、油条和梳打饼干)中铝的含量.样品置于密闭聚四氟乙烯消解罐中经HNO3和H2O2混合溶液完全消解.对微波消解条件、灰化温度和原子化温度进行了优化.确定最佳实验条件为:消解液HNO3和H2O2体积比7∶1,微波功率1 000 W,190℃消解4... 相似文献
930.
为提高传统光滑粒子动力学(smoothed particle hydrodynamics, SPH)方法模拟瞬态热传导问题的精度和稳定性,本文提出了一种一阶对称光滑粒子动力学(first order symmetric SPH, FO-SSPH)方法.该方法将具有二阶热传导方程分解成两个一阶偏微分方程,然后基于梯度离散和Taylor级数展开思想,对一阶核梯度形式进行修正,并将得到的局部矩阵对称化.数值结果表明:与传统SPH方法相比,FO-SSPH方法精度高、数值稳定性好; 该方法能较准确地直接施加混合边值
关键词:
瞬态热传导
光滑粒子动力学
非线性 相似文献