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31.
Superconducting La1.937Sr0.063CuO4 crystals grown by the travelling-solvent floating-zone technique were thermally treated under various temperatures and oxygen pressures for moderately adjusting the oxygen content. The response of intrinsic electronic property of the crystals to the change of hole density in La2-xSrxCuO4 in the vicinity of the magic doping of x= 1/16 (= 0.0625) is studied in detail by magnetic measurements under various fields up to 1 T. It is found that when the superconducting critical temperature (Tc) increases with the oxygen content, there appears also a new subtle electronic state that can be detected from the differential curves of diamagnetic susceptibility dx/dT of the crystal sample. In contrast with the intrinsic state, the new subtle electronic state is very fragile under the magnetic fields. Our results indicate that a moderate change in oxygen doping does not significantly modify the intrinsic electronic state originally existing at the magic doping level. 相似文献
32.
环上的广义导子与Von Neumann代数上的P-核值保持映射 总被引:4,自引:0,他引:4
设A是B(H)的子代数,ψ是A到A的线性映射,且对A中的每个正交投影算子p,有ψ(p)(kerp)ranp,则称ψ是A到A的P-核值保持映射,本文主要得到如下结果:每个2-非绕的半素环上的广义Jordan导子都是广义导子;每个VonNeumann代数上的范数拓扑连续的P-核值保持映射是广义内导子. 相似文献
33.
Cheng-Ling Pan Chang-Min Hou Lei Zhang Yong Fan Shao-Ding Sheng 《Mendeleev Communications》2012,22(2):109-110
The reaction of potassium pyridyl amido ligand {L = [N(R)(2-C5H3N-6-Me)]–, R = CH2But} with YbI2(thf)2 afforded the linear polymeric complex [K0.5(L)3YbiiK0.5]n, which was characterized by X-ray structure analysis. 相似文献
34.
在构建的光学读出微梁阵列(焦平面阵列FPA)非制冷红外成像系统中,实现了无硅基底FPA置于空气中对人体的热成像. 通过FPA在不同真空度环境条件下的成像结果进行比较,分析了热导和系统噪声值随气压变化的关系,以及对系统成像性能的影响,并对气体分子热运动自由程大于空气传热层特征尺度时的气体热传导模型进行了修正分析和实验验证. 实验结果表明:FPA置于空气中时,气体分子撞击微梁引起的微梁反光板无序振动产生的光学读出噪声成为系统噪声的主要来源. 当真空度小于1Pa时,总热导和光学读出噪声值的变化都趋于平缓;当真空度小于10-2Pa时,空气热导的影响可忽略,总热导降低到微梁感热像素的辐射极限,光学读出噪声也降低到一极小值. 实验结果与理论分析相符合.
关键词:
非制冷红外成像
光学读出
双材料微梁阵列
热导 相似文献
35.
An effective approach for the direct benzylhalogenation with in situ generation of hypervalent halides has been developed.A variety of benzyl halides are produced in moderate to excellent yields(up to 99%) with high regioselectivities.UV absorption spectrum is employed to detect the formation of ferr-butyl hypoiodite. 相似文献
36.
Chi Fang Ting Xiong Jie Hou Jing Wei Gu Mei Hu Sheng 《Journal of Dispersion Science and Technology》2013,34(4):604-610
Amidoxime (AO)/amine co-functionalized polypropylene fiber adsorbents were prepared. The all-polymeric structures were characterized by using Fourier transform infrared spectroscopy (FTIR), optical microscope, contact angle meter and electron spin resonance (ESR) analysis methods, confirming the grafting, modification, and amidoximation stages gravimetrically, spectroscopically, and visually. The properties for the removal of uranyl(VI) from aqueous solutions were investigated. For amidoxime (AO) fiber, high adsorption rate was observed within the first 30 minutes and the plateau value of 40.6% uranium loading (0.0812 mg/g) was reached at around 30 minutes. The adsorption equilibrium for AO/amine fiber was attained within 20 minutes, resulting in the adsorption of 92.6% uranium loading (0.185 mg/g). The percentage of adsorption increases with increasing pH value (2–6), reaches a maximum at pH 6.0 and then remains almost constant for AO/amine fiber, whereas reduces slightly for AO fiber. 相似文献
37.
38.
Chao He Xiaohui Zhang Ruofeng Huang Jing Pan Jiaqiang Li Xuege Ling Yan Xiong Xiangming Zhu 《Tetrahedron letters》2014
Under open-flask conditions, an efficient method to assemble a series of diversely functionalized diarylketones in the presence of commercially available NBS has been developed. Yields of up to 99% have been achieved employing diarylmethanes as starting material. Based on 18O-labeled experiment, the addition of stoichiometric water eventually leads to excellent yields in all carbonylation cases. 相似文献
39.
Dongliang Tang Changtao Wang Zeyu Zhao Yanqin Wang Mingbo Pu Xiong Li Ping Gao Xiangang Luo 《Laser \u0026amp; Photonics Reviews》2015,9(6):713-719
Conventional optics is diffraction limited due to the cutoff of spatial frequency components, and evanescent waves allow subdiffraction optics at the cost of complex near‐field manipulation. Recently, optical superoscillatory phenomena were employed to realize superresolution lenses in the far field, but suffering from very narrow working wavelength band due to the fragility of the superoscillatory light field. Here, an ultrabroadband superoscillatory lens (UBSOL) is proposed and realized by utilizing the metasurface‐assisted law of refraction and reflection in arrayed nanorectangular apertures with variant orientations. The ultrabroadband feature mainly arises from the nearly dispersionless phase profile of transmitted light through the UBSOL for opposite circulation polarization with respect to the incident light. It is demonstrated in experiments that subdiffraction light focusing behavior holds well with nearly unchanged focal patterns for wavelengths spanning across visible and near‐infrared light. This method is believed to find promising applications in superresolution microscopes or telescopes, high‐density optical data storage, etc.
40.
Wangyu Li Mingteng Xiong Xiao Liang Dungai Wang Heping Zhu Prof. Dr. Yuanjiang Pan 《ChemistryOpen》2022,11(1):e202100268
An electro-oxidative cyclization pathway in which hydrazones are selected as starting materials to generate amphiphiles by reacting with benzylamines and benzamides was reported. This strategy successfully prepared a series of 1,2,4-triazoles in satisfactory yields. Moreover, the use of cheap stainless steel as the anode, the feasibility to conduct the transformation as a one-pot reaction and the proof that scaling-up these reactions is possible make this transformation attractive for potential application in industry. 相似文献