全文获取类型
收费全文 | 102篇 |
免费 | 4篇 |
国内免费 | 3篇 |
专业分类
化学 | 74篇 |
数学 | 12篇 |
物理学 | 23篇 |
出版年
2023年 | 1篇 |
2022年 | 6篇 |
2021年 | 13篇 |
2020年 | 9篇 |
2019年 | 8篇 |
2018年 | 3篇 |
2017年 | 4篇 |
2016年 | 1篇 |
2015年 | 1篇 |
2014年 | 7篇 |
2013年 | 4篇 |
2012年 | 4篇 |
2011年 | 9篇 |
2010年 | 9篇 |
2009年 | 1篇 |
2008年 | 1篇 |
2007年 | 5篇 |
2006年 | 9篇 |
2005年 | 2篇 |
2004年 | 1篇 |
2003年 | 2篇 |
2002年 | 1篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1997年 | 2篇 |
1979年 | 1篇 |
1968年 | 1篇 |
1964年 | 1篇 |
1962年 | 1篇 |
排序方式: 共有109条查询结果,搜索用时 312 毫秒
21.
The kinetics of H2O2 decomposition have been investigated using ZrO2 supported with transition metal ions including CuII, AgI, HgII, CoII, MnII, NiII and FeIII. At pH = 6.8, the reaction rate exhibits a first order dependence on the initial H2O2 concentration at low concentrations. The order of activity of the different catalysts is strongly dependent on the [H2O2]0 used. The reaction proceed via the formation of the peroxo-intermediate which has an inhibiting effect on the reaction rate. The rate increases with increasing pH, and attains a limiting rate at higher pH's. A reaction mechanism is proposed involving liberation of HO2 radicals from the peroxo-intermediate as the rate-determining step. 相似文献
22.
Bioanalysis is a fast growing domain with new technological developments in the field of mass spectrometry, separation science, and bioinformatics. The central role of separation prior to detection and evaluation of analytes is indisputable. In fact, since the decipherment of the human genome via multichannel capillary electrophoresis in combination with laser-induced fluorescence [1], the analysis of the proteome, i.e., the type and amount of all proteins expressed at a certain time by the genome in a cell or tissue [2] became of central interest. Therefore, new fast and sensitive capillary liquid chromatographic, electrophoretic, and electrochromatographic separation techniques, suitable for high-throughput analysis of proteins, peptides and nucleic acids, are required. 相似文献
23.
In this review the most important techniques developed to hyphenate CE to MALDI-TOF-MS are summarized. The principles of the different interfaces and ways to solve the hyphenation problem are explained and discussed in detail. The most important applications especially in the proteomic field are reviewed, and the advantages of CE-MALDI-TOF-MS for the analysis of these compounds compared to other techniques such as ESI-MS are exhaustingly discussed from a critical point of view. CE coupled to MALDI-TOF-MS has started to overpass traditionally used CE-coupling techniques, especially CE-ESI-MS, offering the possibility to analyze samples of interest even weeks after CE analysis and using multiplexing systems for high-sample throughput. 相似文献
24.
25.
26.
Ania Alik Chafiaa Bouguechtouli Manon Julien Dr. Wolfgang Bermel Rania Ghouil Dr. Sophie Zinn-Justin Dr. Francois-Xavier Theillet 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(26):10497-10501
Abundant phosphorylation events control the activity of nuclear proteins involved in gene regulation and DNA repair. These occur mostly on disordered regions of proteins, which often contain multiple phosphosites. Comprehensive and quantitative monitoring of phosphorylation reactions is theoretically achievable at a residue-specific level using 1H-15N NMR spectroscopy, but is often limited by low signal-to-noise at pH>7 and T>293 K. We have developed an improved 13Cα-13CO correlation NMR experiment that works equally at any pH or temperature, that is, also under conditions at which kinases are active. This allows us to obtain atomic-resolution information in physiological conditions down to 25 μm . We demonstrate the potential of this approach by monitoring phosphorylation reactions, in the presence of purified kinases or in cell extracts, on a range of previously problematic targets, namely Mdm2, BRCA2, and Oct4. 相似文献
27.
Journal of Cluster Science - The effective entrapment of drugs into nanoparticles is one of the most important features during nanoparticles preparation. The percentage loaded drug into the... 相似文献
28.
M. K. Suleymanov R. G. Nazmitdinov E. I. Shahaliev O. B. Abdinov A. Ajaz A. Zaman K. H. Khan Z. Wazir 《Bulletin of the Russian Academy of Sciences: Physics》2012,76(10):1089-1092
A new statistical method is proposed for the analysis of experimental data obtained in nucleus-nucleus collisions at high energies which borrows from ideas developed using the Random Matrix Theory. The method allows us to detect regions with correlation effects in the momentum distributions of secondary particles. 相似文献
29.
Heba A. Raslan Rania M. Mohamed 《International Journal of Polymer Analysis and Characterization》2018,23(2):181-192
Biocomposites of waste polypropylene (WPP) with bagasse fiber as reinforcing component can be readily prepared based on waste management application. Bagasse was subjected to chemical treatments using sodium hydroxide (NaOH) and vinyl triethoxysilane to modify the fiber properties. Scanning electron microscope and Fourier-transform infrared spectroscopy were used to elucidate fiber modification after treatments. Compounding of WPP at various ratios of bagasse was produced by melt mixing. Treated and untreated fiber composites were investigated under conditions of gamma irradiation at 20?kGy. In general behavior, at different fiber loadings, treated biocomposites have better properties than untreated one and fiber treated with silane is the best. Furthermore, treated biocomposites represented more biodegradability under soil than untreated one. The results of mechanical properties showed that the as-prepared fiber composites have superior irradiation-resistant properties. 相似文献
30.
Rania A. Ghazy Mohammed Amoon Hanaa A. Abdallah Nawal A. El-Fishawy Mohiy M. Hadhoud Moawad I. Dessouky Saleh A. Alshebeili Fathi E. Abd El-Samie 《Optik》2014
Watermarking is a solution to the problem of copyright protection of multimedia documents over the Internet. This paper presents a block based watermarking scheme using the singular value decomposition (SVD) algorithm to embed encrypted watermarks into digital images. The paper compares between the traditional method of Liu and the proposed method for embedding encrypted watermarks. Also, a permutation based encryption algorithm and a diffusion based encryption algorithm are compared as the watermark encryption algorithms. Experimental results show that the proposed method is superior to the traditional method of Liu for embedding encrypted watermarks and extracting them efficiently under attacks. Results also show that it is preferred to use permutation based encryption algorithms than diffusion based encryption algorithms for watermark encryption due to their lower sensitivity to attacks. 相似文献