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991.
Yahuan Huan Tiantian Luo Xiaocang Han Jun Ge Fangfang Cui Lijie Zhu Jingyi Hu Feipeng Zheng Xiaoxu Zhao Lili Wang Jian Wang Yanfeng Zhang 《Advanced materials (Deerfield Beach, Fla.)》2023,35(1):2207276
Exploring new-type 2D magnetic materials with high magnetic transition temperature and robust air stability has attracted wide attention for developing innovative spintronic devices. Recently, intercalation of native metal atoms into the van der Waals gaps of 2D layered transition metal dichalcogenides (TMDs) has been developed to form 2D non-layered magnetic TMDs, while only succeeded in limited systems (e.g., Cr2S3, Cr5Te8). Herein, composition-controllable syntheses of 2D non-layered iron selenide nanosheets (25% Fe-intercalated triclinic Fe5Se8 and 50% Fe-intercalated monoclinic Fe3Se4) are firstly reported, via a robust chemical vapor deposition strategy. Specifically, the 2D Fe5Se8 exhibits intrinsic room-temperature ferromagnetic property, which is explained by the change of electron spin states from layered 1T'-FeSe2 to non-layered Fe-intercalated Fe5Se8 based on density functional theory calculations. In contrast, the ultrathin Fe3Se4 presents novel metallic features comparable with that of metallic TMDs. This work hereby sheds light on the composition-controllable synthesis and fundamental property exploration of 2D self-intercalation induced novel TMDs compounds, by propelling their application explorations in nanoelectronics and spintronics-related fields. 相似文献
992.
993.
在介绍SNMPv1协议的基础上讨论了SNMPv2协议的特点及对SNMPv1的改进,并分析了SNMPv1和SNMPv2的共存问题。 相似文献
994.
韩明荣 《重庆科技学院学报(社会科学版)》1998,(1)
就诱导、发展学生兴趣,注重能力培养,引入反馈——强化矫正措施等教学法进行了浅析,并探讨了其在冶金物理化学课教学中的应用。 相似文献
995.
系统辨识广泛应用于工程实践面临的主要问题是算法的快速性,状态空间模型辨识更是如此,本文提出的改进的双Householder变换就是利用数据矩阵的特殊结构Hankel矩阵和Toiplitz矩阵;再利用移位算子的性质,对数据矩阵实施变换,从而快速地求解矩阵的逆和正交补,进而可以提高辨识算法的快速性和精确度 相似文献
996.
An amplitude-sensitive optical heterodyne polarimeter was set up to monitor noninvasively the aqueous glucose concentration in a rabbit's eye. A Zeeman laser in conjunction with a Glan-Thompson analyzer was used to generate an optical heterodyne signal. The amplitude of the heterodyne signal linearly related to the optical rotation angle of the aqueous glucose. The concentration of the aqueous glucose in a rabbit's eyeball was measured in vivo. There was a 30-min time delay between observations of aqueous glucose and blood glucose. The detection capability and the reproducibility of the experiment are demonstrated and discussed. 相似文献
997.
Graphic analysis of the effective reflectivity of antireflection-coated films on diode facets 总被引:1,自引:0,他引:1
The wavelength dependence of the reflectivity of AR-coated facets and carrier density in relation to peak wavelength of the gain profile have been taken into consideration to study a one-facet AR-coated semiconductor diode laser. A graphic analysis method is developed to study cases in which analytical expressions of the reflectivity curves cannot be extracted. Results show that the upper bound of the carrier density that can be established inside the diode is generally (sometimes to a considerable degree) smaller than that determined by the claimed minimum reflectivity if the spectral width of the reflectivity curve cannot be regarded as infinite. This implies that the effective reflectivity of the AR-coated facet is generally larger than the claimed minimum reflectivity. To increase the effectiveness of AR film, it is essential to maintain tight control of the wavelength at which the reflectivity curve is minimum. 相似文献
998.
有载调压变压器调整对电力系统电压稳定性的影响 总被引:8,自引:1,他引:7
本文利用分叉理论,在静态范围讨论了有载调压变压器分接头调整电力系统电压稳定性影响问题,研究表明,对应于不同负荷模型,有载调压变器变比变化对电压失稳静分叉点的“迁移”方向,最终位置,调压效应产生很大影响,此外,研究发现,一些负荷模型在一定负载区域内,有载调压变压器分接头调整还会产生复杂的“混合调压效应”现象。 相似文献
999.
Crystallization of proteins by liquid liquid diffusion method was performed in microgravity using the MDA Minilab aboard the US Space Shuttle. Three proteins, namely lysozyme, trichosanthin, and a new lechin, were crystallized in the space experiment. In contrast to the results of space experiments with a tube-like vapor diffusion method, the crystallization conditions for growing better crystals in space are remarkably different from the conditions optimized on earth. This may be due to difficulties in ground optimization, which are caused by gravity-dependent phenomena, in particular the specific convective flow occurring with liquid liquid diffusion. 相似文献
1000.
We investigate classes of sets that can be decided by bounded truth-table reductions to an NP set in which evaluators donothave full access to the answers to the queries but get only restricted information such as the number of queries that are in the oracle set or even just this number modulom, for somem?2. We also investigate the case in which evaluators are nondeterministic. We show that when we vary the information that the evaluators get, this can change the resulting power of the evaluators. We locate all these classes within levels of the Boolean hierarchy which allows us to compare the complexity of such classes. 相似文献