全文获取类型
收费全文 | 53篇 |
免费 | 1篇 |
国内免费 | 1篇 |
专业分类
化学 | 25篇 |
晶体学 | 1篇 |
力学 | 2篇 |
数学 | 1篇 |
物理学 | 26篇 |
出版年
2017年 | 2篇 |
2016年 | 1篇 |
2015年 | 1篇 |
2013年 | 2篇 |
2012年 | 1篇 |
2011年 | 3篇 |
2010年 | 1篇 |
2009年 | 2篇 |
2008年 | 2篇 |
2007年 | 4篇 |
2006年 | 2篇 |
2005年 | 1篇 |
2004年 | 3篇 |
2003年 | 2篇 |
2002年 | 5篇 |
2001年 | 3篇 |
2000年 | 5篇 |
1999年 | 3篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1980年 | 2篇 |
1970年 | 1篇 |
排序方式: 共有55条查询结果,搜索用时 265 毫秒
11.
Y. Hwu W. L. Tsai B. Lai J. H. Je G. H. Fecher M. Bertolo G. Margaritondo 《Surface science》2001,480(3):188-195
We present several successful test cases of using photoelectron emission microscopy (PEEM) for photon energy up to 25 keV. First, the full extended X-ray absorption fine structure analysis was implemented in areas as small as 100 μm2 for transition-metal K edge absorption spectra and, therefore, demonstrated the feasibility of combining structural and chemical analysis with hard-X-ray absorption spectroscopy with high lateral resolution. We also show that PEEM can be used in a transmission (radiography) mode as an imaging detector for hard-X-ray. This approach again leads to the unprecedented 0.3 μm lateral resolution, particularly critical for the use of coherence-based phase contrast techniques in real time X-ray radiology. 相似文献
12.
13.
[reaction: see text] Although the indole N-phosphinoyl derivative 4 undergoes n-BuLi deprotonation/electrophile quench to afford C-7-substituted products, its deprotection requires harsh conditions. On the other hand, the N-amide 12, upon sequential or one-pot C-2 metalation, silylation, C-7 metalation, and electrophile treatment, furnishes indoles 7 in good overall yields. In combination with the Suzuki-Miyaura protocol, C-7 aryl (heteroaryl)-substituted indoles 14 and 16 are obtained, including hippadine and pratosine, members of the pyrrolophenanthridone alkaloid family. 相似文献
14.
15.
16.
G.?TsilimisEmail author G.H.?Fecher J.?Braun J.?Kutzner H.?Zacharias 《Applied Physics A: Materials Science & Processing》2004,78(2):177-181
The surface electronic structure of platinum is investigated by photoemission using extreme ultraviolet light. High-order harmonics of amplified femtosecond Ti:sapphire radiation in the range h=20 to 50eV are employed. In the normal emission spectra of Pt(111), three well-distinguished maxima at fixed kinetic energies of Ekin=10,12.5 and 19eV are observed. These structures, which are far above the Fermi energy, show a strong dependence upon adsorption of CO. This observation and layer-resolved photoemission calculations indicate the surface character of the involved unoccupied platinum states. These empty states are populated by the primary photo-excited electrons, which decay into the unoccupied states due to inelastic scattering. The pronounced emission of the electrons originates mainly from these surface resonances. PACS 79.60.-i; 42.65.Ky; 71.20.-b; 79.20.Hx; 79.60.Dp 相似文献
17.
1H NMR‐based metabolomics exploring urinary biomarkers correlated with proteinuria in focal segmental glomerulosclerosis: a pilot study
下载免费PDF全文
![点击此处可从《Magnetic resonance in chemistry : MRC》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Shiva Kalantari Mohsen Nafar Shiva Samavat Mahmoud Parvin B. Fatemeh Nobakht M.GH. Farnaz Barzi 《Magnetic resonance in chemistry : MRC》2016,54(10):821-826
Focal segmental glomerulosclerosis (FSGS) is a common glomerulonephritis, and its rates of occurrence are increasing worldwide. Proteinuria is a clinical defining feature of FSGS which correlates with the severity of podocyte injury in patients with nephrotic‐range protein excretion. Metabolite biomarkers corresponding with the level of proteinuria could be considered as non‐invasive complementary prognostic factors to proteinuria. The urine samples of 15 patients (n = 6 women and n = 9 men) with biopsy‐proven FSGS were collected and subjected to nuclear magnetic resonance (NMR) analysis for metabolite profiling. Multivariate statistical analyses, including principal component analysis and orthogonal projection to latent structure discriminant analysis, were applied to construct a predictive model based on patients with proteinuria >3000 mg/day and <3000 mg/day. In addition, random forest was performed to predict differential metabolites, and pathway analysis was performed to find the defective pathways responsible for proteinuria. Ten metabolites, significant in both statistical methods (orthogonal projection to latent structure discriminant analysis and random forest), were considered as prognostic biomarkers for FSGS: citrulline, dimethylamine, proline, acetoacetate, alpha‐ketoisovaleric acid, valine, isobutyrate, D‐Palmitylcarnitine, histidine, and N‐methylnicotinamide. Pathway analysis revealed impairment of the branched‐chain amino acid degradation pathways in patients with massive proteinuria. This study shows that metabolomics can reveal the molecular changes corresponding with disease progression in patients with FSGS and provide a new insight for pathogenic pathways. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
18.
Efficient spin injector scheme based on Heusler materials 总被引:1,自引:0,他引:1
Chadov S Graf T Chadova K Dai X Casper F Fecher GH Felser C 《Physical review letters》2011,107(4):047202
We present a rational design scheme intended to provide stable high spin polarization at the interfaces of the magnetoresistive junctions by fulfilling the criteria of structural and chemical compatibilities at the interface. This can be realized by joining the semiconducting and half-metallic Heusler materials with similar structures. The present first-principles calculations verify that the interface remains half-metallic if the nearest interface layers effectively form a stable Heusler material with the properties intermediately between the surrounding bulk parts. This leads to a simple rule for selecting the proper combinations. 相似文献
19.
Ouardi S Fecher GH Kozina X Stryganyuk G Balke B Felser C Ikenaga E Sugiyama T Kawamura N Suzuki M Kobayashi K 《Physical review letters》2011,107(3):036402
This study reports on the linear dichroism in angular-resolved photoemission from the valence band of the Heusler compounds NiTi0.9Sc0.1Sn and NiMnSb. High-resolution photoelectron spectroscopy was performed with an excitation energy of hν = 7.938 keV. The linear polarization of the photons was changed using an in-vacuum diamond phase retarder. The valence band spectra exhibit the typical structure expected from first-principles calculations of the electronic structure of these compounds. Noticeable linear dichroism is found in the valence band of both materials, and this allows for a symmetry analysis of the contributing states. The differences in the spectra are found to be caused by symmetry-dependent angular asymmetry parameters, and these occur even in polycrystalline samples without preferential crystallographic orientation. 相似文献
20.
S.A. Nepijko M. Klais A. Oelsner O. Schmidt G.H. Fecher G. Schönhense U. Muschiol C.M. Schneider S. Zennaro N. Zema N.N. Sedov 《Applied Physics A: Materials Science & Processing》2002,74(2):295-298
It is shown that magnetic X-ray circular dichroism (MXCD) can be exploited in photoemission electron microscopy not only to
visualize the domain structure of ferromagnets, but also to perform quantitative measurements of the stray magnetic fields
at the domain boundaries. In the general situation, two MXCD images obtained at different extractor voltages are required.
In specific cases, however, it suffices to consider a single image, if it is deformed by the stray magnetic fields compared
to a known object geometry. The object geometry means its real shape, scratches or other defects. It is also possible to deposit
a paramagnetic film structured in the form of stripes or a grid as a reference on the ferromagnetic sample being investigated.
Received: 2 August 2001 / Accepted: 6 September 2001 / Published online: 20 December 2001 相似文献