全文获取类型
收费全文 | 125篇 |
免费 | 2篇 |
专业分类
化学 | 117篇 |
晶体学 | 1篇 |
物理学 | 9篇 |
出版年
2020年 | 1篇 |
2017年 | 3篇 |
2015年 | 3篇 |
2014年 | 1篇 |
2013年 | 11篇 |
2012年 | 4篇 |
2011年 | 9篇 |
2010年 | 7篇 |
2009年 | 7篇 |
2008年 | 5篇 |
2007年 | 10篇 |
2006年 | 8篇 |
2005年 | 12篇 |
2004年 | 7篇 |
2003年 | 3篇 |
2002年 | 3篇 |
2001年 | 3篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1990年 | 1篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1982年 | 1篇 |
1981年 | 3篇 |
1980年 | 3篇 |
1979年 | 5篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1967年 | 2篇 |
1966年 | 1篇 |
排序方式: 共有127条查询结果,搜索用时 15 毫秒
41.
42.
Kuniyuki Kitagawa Toshiki Nanya Shin Tsuge 《Spectrochimica Acta Part B: Atomic Spectroscopy》1981,36(1):9-20
The atomic Faraday effect has been applied to the trace determination of lead in NBS Orchard Leaves, human blood, and volcanic ashes. Suspensions of powder samples and diluted whole blood are directly pipetted into a graphite tube atomizer. Spectroscopic and practical features are discussed of the atomic Faraday effect of lead. The inherent feature of insensitivity to background scattering makes the present technique suitable for practical analysis. The problem associated with loss of transmitted optical energy caused by non-atomic species was overcome by a correction method. Consequently, the present technique enabled us to perform rapid analyses, gave a detection limit of 5 × 10?11 g and fair accuracy, at least satisfactory for practical analysis. Some problems arise from residue build-up in the atomizer. 相似文献
43.
T. Kishikawa 《Journal of Radioanalytical and Nuclear Chemistry》1984,85(5):293-303
Discriminative low energy photon counting is proposed to evaluate coherent and incoherent scattering by atmospheric environments. Isotope X-ray sources with decay mode of E.C. and I.T. are chosen for the test sources of monochromatic X-rays. Distance-depending component of the discriminative counting ratio was involved in the incoherent scattering. 相似文献
44.
Manganese solution was sprayed into a microwave-excited plasma torch (2450 MHz and ca. 200 W), whose profile was examined; the electron temperature, the degree or ionization and the total number of atoms and ions were estimated. Effects of alkali and alkaline earth metals were found to depend on the ionisation potentials of both manganese and the added metal. 相似文献
45.
Phase-selective photochemical reaction of 2-pyridone derivatives was examined. Irradiation of 1 in benzene mainly gave rearrangement products 2. However, intermolecular [4 + 4] photocycloaddition proceeded quantitatively in the solid state, affording photodimers 3. An effective pi-pi stacking and dipole-dipole interaction between two pyridone moieties might play important roles in an effective arrangement of 1 for photodimerization in their crystal structures. [reaction: see text] 相似文献
46.
The recrystallization of Heptakis[6‐O‐tert ‐butyldimethylsilyl)]‐β ‐cyclodextrin ( 1 ) from ethyl acetate gave single crystals of 1 2·(ethyl acetate)3 complex. The superstructure of 12·(ethyl acetate)3 complex was investigated by 1H NMR spectroscopy, molecular modeling, and single crystal/powder X‐ray diffractions. Encapsulation of ethyl acetate molecules with 1 and a unique hexagonal columnar superstructure in its crystal were found. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
47.
Kohei Ueno Eiji Kishikawa Shigeru Inoue Jitsuo Ohta Hiroshi Fujioka Masaharu Oshima Hiroyuki Fukuyama 《固体物理学:研究快报》2014,8(3):256-259
High‐quality AlN epilayers were grown via pulsed sputtering deposition on thermally nitrided sapphire $(11\bar 20)$ with precise control of the N/Al ratio. Under slightly Al‐rich growth conditions, the growth of AlN epilayers on the thermally nitrided sapphire proceeded in a two‐dimensional mode from the initial stage of growth, and their surfaces were atomically flat stepped and terraced structures. The FWHM values of the X‐ray rocking curves were as low as 87 arcsec and 339 arcsec for the 0002 and $1 \bar 102$ diffractions, respectively, at a film thickness of 400 nm. The present approach is therefore quite promising for the low‐cost fabrication of AlGaN‐based UV optical devices. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
48.
Keiki Kishikawa Wongsiri Sankhavasi Makoto Yamamoto Shigeo Kohmoto Kazutoshi Yamada 《合成通讯》2013,43(15):2339-2347
A convenient synthesis of natural (±)-blastmycino-lactol from the aldol addition reaction of n-pentanoylurea and (±)-2-benzyloxypropionaldehyde is described. 相似文献
49.
Lewis acid mediated addition of 5-(tri-n-butylstannyl)methyl-3-methylisoxazole and its analogues with aldehydes have been carried out. Corresponding 5-(β-hydroxy)ethylisoxazoles were obtained in moderate yields, without ring opening of the isoxazole. 相似文献
50.
Graphite electrodes heated by d.c- power alone, or a combination of d.c- and r.f. power, are investigated for generating atomic emission from cadmium with specially designed discharge lamps. Best results are achieved if the plasma produced by both power sources can be concentrated within a cylindrical electrode. 相似文献