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91.
Progress in surface modification of magnetic nanoparticles(MNPs)is summarized with regard to organic molecules,macromolecules and inorganic materials.Many researchers are now devoted to synthesizing new types of multi-functional MNPs,which show great application potential in both diagnosis and treatment of disease.By employing an ever-greater variety of surface modification techniques,MNPs can satisfy more and more of the demands of medical practice in areas like magnetic resonance imaging(MRI),fluorescent marking,cell targeting,and drug delivery. 相似文献
92.
Charge redistribution and a shortening of the Fe—As bond at the quantum critical point of SmO1–xFxFeAs 下载免费PDF全文
Jie Cheng Peng Dong Wei Xu Shengli Liu Wangsheng Chu Xianhui Chen Ziyu Wu 《Journal of synchrotron radiation》2015,22(4):1030-1034
Many researchers have pointed out that there is a quantum critical point (QCP) in the F‐doped SmOFeAs system. In this paper, the electronic structure and local structure of the superconductive FeAs layer in SmO1–xFxFeAs as a function of the F‐doping concentration have been investigated using Fe and As K‐edge X‐ray absorption spectroscopy. Experiments performed on the X‐ray absorption near‐edge structure showed that in the vicinity of the QCP the intensity of the pre‐edge feature at the Fe‐edge decreases continuously, while there is a striking rise of the shoulder‐peak at the As edge, suggesting the occurrence of charge redistribution near the QCP. Further analysis on the As K‐edge extended X‐ray absorption fine structure demonstrated that the charge redistribution originates mostly from a shortening of the Fe—As bond at the QCP. An evident relationship between the mysterious QCP and the fundamental Fe—As bond was established, providing new insights on the interplay between QCP, charge dynamics and the local structural Fe—As bond in Fe‐based superconductors. 相似文献
93.
94.
Wenchang Chu 《Mathematical Methods in the Applied Sciences》2023,46(1):830-839
An expansion formula into bivariate formal power series is established that implies, as consequences, three remarkable identities of partial theta functions due to Warnaar (2003), Schilling–Warnaar (2002) and Andrews–Warnaar (2007). 相似文献
95.
Shengyun Zhu Jiazheng Zhu Minamisono T. Matsuta K. Yongjun Xu Fukuda M. Mihara M. Zhiqiang Wang Sato K. Akai H. Chaofan Rong Chengjie Chu Jun Chen Hailong Luo 《Hyperfine Interactions》2001,136(3-8):149-153
An on-line time differential perturbed angular correlation technique has been developed with the light probe nucleus 19F. The first on-line TDPAC measurement was carried out to determine the field gradient in Cd and quadrupole moment of 19F (0.197 MeV: I
π = 5/2+, T1/2 = 89 ns).
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
96.
考查了在有芳烃卤代物RX(如氯苯、溴苯和碘苯)存在时,四苯基卟吩TPP的荧光衰变现象。基于荧光衰变动力学分析,发现:在RX和TPP之间生成复合物是引起重原子效应的一个基本步骤。荧光衰变的动力学参数则进一步表明:可观察的外部重原子效应主要是由于发生分子间电荷转移相互作用而引起的。 相似文献
97.
98.
99.
L.?Z.?Liu X.?L.?WuEmail author Y.?M.?Yang T.?H.?Li Paul?K.?Chu 《Applied Physics A: Materials Science & Processing》2011,103(2):361-365
Raman spectra acquired from Si
x
Ge1−x
-nanocrystal-embedded SiO2 films show dependence of the Si–Si optical phonon frequency on Si content. The frequency upshifts, and peak intensity increases
as the silicon concentration increases. For a given Si content, the frequency remains unchanged with annealing temperature.
Spectral analysis and density functional theory calculation reveal that the optical Si–Si phonon is related to the formation
of localized Si clusters surrounded by Si/Ge atomic layers in the Si
x
Ge1−x
nanocrystals and the intensity enhancement arises from the larger cluster size. The synergetic effect of surface tensile
stress and phonon confinement determines the Si–Si optical phonon behavior. 相似文献
100.
以橡实淀粉为主要原料,采用熔融挤出法制备了热塑性橡实淀粉(TPAS)和热塑性橡实淀粉(TPAS)/聚己内酯(PCL)二元复合材料.通过对样品FTIR和XRD的分析,研究了乙二醇、丙三醇、乙醇胺、二乙醇胺、三乙醇胺五种不同增塑剂对样品的分子结构的影响,亦研究了不同增塑体系对复合材料分子结构和力学性能的影响.结果表明:五种... 相似文献