全文获取类型
收费全文 | 424篇 |
免费 | 24篇 |
专业分类
化学 | 383篇 |
晶体学 | 7篇 |
力学 | 4篇 |
数学 | 15篇 |
物理学 | 39篇 |
出版年
2023年 | 4篇 |
2021年 | 2篇 |
2020年 | 5篇 |
2019年 | 7篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2016年 | 6篇 |
2015年 | 9篇 |
2014年 | 17篇 |
2013年 | 25篇 |
2012年 | 32篇 |
2011年 | 34篇 |
2010年 | 10篇 |
2009年 | 12篇 |
2008年 | 28篇 |
2007年 | 21篇 |
2006年 | 38篇 |
2005年 | 29篇 |
2004年 | 23篇 |
2003年 | 19篇 |
2002年 | 22篇 |
2001年 | 9篇 |
2000年 | 5篇 |
1999年 | 2篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 2篇 |
1993年 | 4篇 |
1991年 | 3篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1985年 | 3篇 |
1984年 | 5篇 |
1983年 | 8篇 |
1982年 | 6篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1978年 | 8篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1975年 | 4篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1971年 | 2篇 |
1970年 | 2篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1911年 | 2篇 |
1910年 | 2篇 |
排序方式: 共有448条查询结果,搜索用时 15 毫秒
351.
352.
Giacomo Russo Francesco Barbato Damiano Gustavo Mita Lucia Grumetto 《Biomedical chromatography : BMC》2019,33(3)
A quick and inexpensive validated method, based on sample treatment by liquid–liquid microextraction followed by liquid chromatography (LC) coupled with ultraviolet tandem fluorescence detection is proposed for the determination of 15 multiclass pollutants both in serum and in saliva, as a simple and easy to draw matrix. The method was set up and validated according to European guidelines. The compounds of interest include some endocrine‐disrupting chemicals (i.e. bisphenol A, bisphenol B, bisphenol E, bisphenol F, bisphenol AF, bisphenol A diglycidyl ether, bisphenol M, diethylhexyl phthalate, monoethylhexyl phthalate, triclosan and 4‐nonylphenol), as well as other pollutants belonging to the class of volatile organic compounds (2‐chlorophenol, 1,2 dichlorobenzene, 1,2,4,5‐tetrachlorobenzene). The limits of quantifications ranged from 2.28 × 10?3 μg mL?1 (bisphenol A diglycidyl ether) to 6.29 μg mL?1 (diethylhexyl phthalate), while those of detection ranged from 0.068 × 10?3 μg mL?1 (bisphenol A diglycidyl ether) to 1.031 μg mL?1 (diethylhexyl phthalate). To test method suitability, it was applied to real saliva and serum samples of healthy human volunteers and was found to meet the demands of the laboratories handling simple and relatively inexpensive equipment for screening oriented at rapid and reliable contamination assessment of a population. 相似文献
353.
Dr. Hiroki Hayashi Dr. Hideaki Takano Hitomi Katsuyama Dr. Yu Harabuchi Prof. Satoshi Maeda Prof. Tsuyoshi Mita 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(39):10040-10047
A three-component reaction (3CR) for the synthesis of difluoroglycine derivatives has been achieved by using amines, difluorocarbene (generated in situ), and the abundant, inexpensive, and nontoxic C1 source CO2. Various tert-amines and pyridine, (iso)quinoline, imidazole, thiazole, and pyrazole derivatives were incorporated, and the corresponding products were isolated in solid form without purification by column chromatography on silica gel. Detailed reaction profiles of the 3CR were obtained from computational analysis using DFT calculations, and the results critically suggest that simple ammonia is not applicable to this reaction. In addition, as strongly supported by computational predictions, a new reagent that can generate difluorocarbene at 0 °C without any additives was discovered. Finally, radical substitution reactions of the obtained difluoroglycine derivatives under photoredox conditions, as well as a synthetic application as an N-heterocyclic carbene ligand are shown. 相似文献
354.
Naruyoshi Mita Shin‐ichiro Tawaki Hiroshi Uyama Shiro Kobayashi 《Macromolecular bioscience》2002,2(3):127-130
The peroxidase‐catalyzed polymerization of phenol in aqueous solution has been examined in the presence of 2,6‐di‐O‐methyl‐α‐cyclodextrin (DM‐α‐CD). By the addition of DM‐α‐CD, the phenol was polymerized in a buffer to produce the soluble polyphenol. Only a catalytic amount of DM‐α‐CD induced the polymerization effectively. A small amount of DM‐α‐CD was contained in the polymer. 相似文献
355.
356.
357.
Development of an AND Logic‐Gate‐Type Fluorescent Probe for Ratiometric Imaging of Autolysosome in Cell Autophagy
下载免费PDF全文
![点击此处可从《Chemistry (Weinheim an der Bergstrasse, Germany)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Ippei Takashima Ryosuke Kawagoe Prof. Dr. Itaru Hamachi Prof. Dr. Akio Ojida 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(5):2038-2044
The concomitant detection of two biological events facilitates the highly selective and sensitive analysis of specific biological functions. In this article, we report an AND logic‐gate‐type fluorescent probe that can concurrently sense two biological events in living cells: H2O2 accumulation and acidification. The probe exhibits a unique fluorescence sensing mechanism, in which a xanthene fluorophore is oxidatively transformed to a xanthone derivative by H2O2, thereby resulting in a clear dual‐emission change. This transformation is significantly accelerated under weak acidic conditions, which enables the selective and sensitive detection of H2O2 production in an acidic cellular compartment. This unique sensing property was successfully applied to the ratiometric fluorescence imaging of autolysosome formation in selective mitochondrial autophagy (mitophagy), which highlights the utility of this novel probe in autophagy research. 相似文献
358.
359.
Prof. Dr. Itaru Nakamura Arinobu Hirayama Dr. Shinya Gima Prof. Dr. Masahiro Terada 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(68):15816-15820
The Au-catalyzed reactions of O-homopropaylic oximes afforded the 3-alkenylated isoxazolines in good to high yields. The mechanistic studies suggest that the reaction proceeds through an exo-cyclization followed by intermolecular methylene group transfer. In addition, oligomeric species of the starting material were observed in the reaction mixture by mass spectra, supporting our proposed mechanism, which proceeds through a repeated intermolecular C−C bond forming process. 相似文献
360.
Akimi Serizawa Isao Kataoka Itaru Michiyoshi 《International Journal of Multiphase Flow》1975,2(3):221-233
This paper, the first in a series describing our work on the turbulence structure of air-water bubbly flow, describes the principles of measurement and specially developed electronic instrumentation for determining various important local parameters, and the rates of turbulent transport of heat and bubbles in air-water two-phase bubbly flow. These instruments indicate the phase distribution, the bubble velocity and its spectrum, the water velocity and the turbulent intensity, and the turbulent dispersion coefficient of bubbles. Brief discussions are also presented on the accuracy of these techniques. 相似文献