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排序方式: 共有112条查询结果,搜索用时 15 毫秒
1.
2.
In this paper, the authors use Glimm scheme to study the global existence of BV solutions to Cauchy problem of the pressure-gradient system with large initial data. To this end, some important properties of the shock curves of the pressure-gradient system in the Riemann invariant coordinate system and verify that the shock curves satisfy Diperna’s conditions (see [Diperna, R. J., Existence in the large for quasilinear hyperbolic conservation laws, Arch. Ration. Mech. Anal., 52(3), 1973, 244–257]) are studied. Then they construct the approximate solution sequence through Glimm scheme. By establishing accurate local interaction estimates, they prove the boundedness of the approximate solution sequence and its total variation. 相似文献
3.
LetM be a compact minimal surface inS
3. Y. J. Hsu[5] proved that if S222, thenM is either the equatorial sphere or the Clifford torus, whereS is the square of the length of the second fundamental form ofM, ·2 denotes theL
2-norm onM. In this paper, we generalize Hsu's result to any compact surfaces inS
3 with constant mean curvature.Supported by NSFH. 相似文献
4.
5.
Hui Li Zejun Jiang Xiaolin Cao Hang Su Hua Shao Fen Jin Lufei Zheng A. M. Abd El-Aty Jing Wang 《Chromatographia》2018,81(2):359-364
6.
Electrochemical blocking is a type of single-entity electrochemical measurement particularly well adapted to the detection of insulating particles. The digital detection of ultralow concentrations of artificial entities such as polymer particles or biotargets such as proteins and bacteria represents an exceptional opportunity for sensing applications. In this review, we explore the latest development in the field of electrochemical blocking and propose some perspectives. 相似文献
7.
Hydrogen Treatment for Superparamagnetic VO2 Nanowires with Large Room‐Temperature Magnetoresistance
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Zejun Li Yuqiao Guo Prof. Zhenpeng Hu Jihu Su Jiyin Zhao Junchi Wu Jiajing Wu Yingcheng Zhao Prof. Changzheng Wu Prof. Yi Xie 《Angewandte Chemie (International ed. in English)》2016,55(28):8018-8022
One‐dimensional (1D) transition metal oxide (TMO) nanostructures are actively pursued in spintronic devices owing to their nontrivial d electron magnetism and confined electron transport pathways. However, for TMOs, the realization of 1D structures with long‐range magnetic order to achieve a sensitive magnetoelectric response near room temperature has been a longstanding challenge. Herein, we exploit a chemical hydric effect to regulate the spin structure of 1D V–V atomic chains in monoclinic VO2 nanowires. Hydrogen treatment introduced V3+ (3d2) ions into the 1D zigzag V–V chains, triggering the formation of ferromagnetically coupled V3+–V4+ dimers to produce 1D superparamagnetic chains and achieve large room‐temperature negative magnetoresistance (?23.9 %, 300 K, 0.5 T). This approach offers new opportunities to regulate the spin structure of 1D nanostructures to control the intrinsic magnetoelectric properties of spintronic materials. 相似文献
8.
Yuqin Yao Zhihui Cheng Haoyu Ye Yongmei Xie Jing He Minghai Tang Tao Shen Jiangman Wang Yan Zhou Zejun Lu Feng Luo Lijuan Chen Luoting Yu Jin‐Liang Yang Aihua Peng Yuquan Wei 《Journal of separation science》2010,33(9):1331-1337
Ansamitocin P‐3 is a potent anti‐tumor maytansinoid found in Actinosynnema pretiosum. However, due to the complexity of the fermentation broth of Actinomycete, how to effectively separate ansamitocin P‐3 is still a challenge. In this study, both analytical and preparative high‐performance counter‐current chromatography were successfully used to separate and purify ansamitocin P‐3 from fermentation broth. A total of 28.8 mg ansamitocin P‐3 with purity of 98.4% was separated from 160 mg crude sample of fermentation broth in less than 80 min with the two‐phase solvent system of hexane–ethyl acetate–methanol–water (0.6:1:0.6:1, v/v/v/v). The purity and structural identification were determined by HPLC, 1H NMR, 13C NMR and mass spectroscopy. 相似文献
9.
It is previously found that the two-dimensional (2D) electron-pair in a homogeneous magnetic field has a set of exact solutions
for a denumerably infinite set of magnetic fields. Here we demonstrate that as a function of magnetic field a band-like structure
of energy associated with the exact pair states exists. A direct and simple connection between the pair states and the quantum
Hall effect is revealed by the band-like structure of the hydrogen “pseudo-atom”. From such a connection one can predict the
sites and widths of the integral and fractional quantum Hall plateaus for an electron gas in a GaAs-Al
x
Ga1−x
As heterojunction. The results are in good agreement with the existing experimental data. 相似文献
10.
We classify spacelike hypersurfaces of the de Sitter space with constant scalar curvature and with two principal curvatures. Moreover, we prove that if Mn is a complete spacelike hypersurface with constant scalar curvature n(n−1)R and with two distinct principal curvatures such that the multiplicity of one of the principal curvatures is n−1, then R<(n−2)c/n. Additionally, we prove several rigidity theorems for such hypersurfaces. 相似文献