全文获取类型
收费全文 | 301篇 |
免费 | 3篇 |
专业分类
化学 | 135篇 |
晶体学 | 7篇 |
力学 | 5篇 |
数学 | 27篇 |
物理学 | 130篇 |
出版年
2022年 | 6篇 |
2021年 | 2篇 |
2020年 | 8篇 |
2019年 | 5篇 |
2018年 | 10篇 |
2017年 | 12篇 |
2016年 | 19篇 |
2015年 | 3篇 |
2014年 | 14篇 |
2013年 | 16篇 |
2012年 | 11篇 |
2011年 | 15篇 |
2010年 | 4篇 |
2009年 | 10篇 |
2008年 | 13篇 |
2007年 | 17篇 |
2006年 | 14篇 |
2005年 | 6篇 |
2004年 | 12篇 |
2003年 | 4篇 |
2002年 | 10篇 |
2001年 | 8篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1995年 | 5篇 |
1994年 | 5篇 |
1993年 | 4篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1990年 | 5篇 |
1989年 | 3篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 4篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1978年 | 4篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1969年 | 4篇 |
1968年 | 1篇 |
1967年 | 2篇 |
排序方式: 共有304条查询结果,搜索用时 0 毫秒
1.
A forecasting model is developed for the number of daily applications for loans at a financial services telephone call centre. The purpose of the forecasts and the associated prediction intervals is to provide effective staffing policies within the call centre. The model building process is constrained by the availability of only 2 years and 7 months of data. The distinctive feature of the data is that demand is driven in the main by advertising. The analysis given focuses on applications stimulated by press advertising. Unlike previous analyses of broadly similar data, where ARIMA models were used, a model with a dynamic level, multiplicative calendar effects and a multiplicative advertising response is developed and shown to be effective. 相似文献
2.
3.
Stewart C Zieminski A Blessing S Crittenden R Draper P Dzierba A Heinz R Krider J Marshall T Martin J Sambamurti A Smith P Sulanke T Gomez R Dauwe L Haggerty H Malamud E Nikolic M Hagopian S Abrams R Ares J Goldberg H Halliwell C Margulies S McLeod D Salminen A Solomon J Wu G Ellsworth R Goodman J Gupta S Yodh G Watts T Abramov V Antipov Y Baldin B Denisov S Glebov V Gorin Y Kryshkin V Petrukhin A Polovnikov S Sulyaev R 《Physical review D: Particles and fields》1990,42(5):1385-1395
4.
V. V. Chernaya R. V. Shpanchenko Yu. A. Velikodnyi M. L. Kovba E. V. Antipov 《Russian Journal of Inorganic Chemistry》2006,51(5):779-784
The crystal structure of anhydrous K4V2O7 (I) is determined by powder X-ray diffraction. The compound crystallizes in the monoclinic system (a = 10.222(1) Å, b = 6.2309(8) Å, c = 7.282(1) Å, β = 101.31(1)°, space group C2/m, Z = 2). The structure contains layers of isolated V2O7 pyrovanadate groups separated by layers of potassium cations. The hydration and dehydration of I are studied by thermal analysis and high-temperature X-ray diffraction. The dehydration is accompanied by decomposition of the starting crystal hydrate to give intermediate compounds. Anhydrous compound I undergoes a reversible phase transition at 740°C. The high-temperature phase is assumed to have a hexagonal unit cell (a = 6.169(4) Å, c = 15.72(1) Å, Z = 2). 相似文献
5.
E. Gilbert G. V. Veriovkin V. A. Mikhailov N. I. Antipov V. N. Nikitin 《Journal of Radioanalytical and Nuclear Chemistry》1977,38(1-2):147-154
Two previously developed methods of noble metal neutron activation (NA) determination have been applied for the analysis of
technological materials. While comparing the data obtained by both methods with those obtained in Central Chemical Laboratory
the systematical discreapences have been shown to be absent. A new method of Pd, Au, Pt and Ir NA determination in natural
and technological specimens based on the selective extraction of Pd and Au preliminary to irradiation has been developed.
Results of the analysis of “Glomar Cellenger”'s deep-water drilling samples are discussed obtained by this method. 相似文献
6.
On the Crystal Structure of CaLaAl3O7 and CaLaGa3?xAlxO7 (x = 0.66) Single crystals of (I): CaLaAl3O7 and (II): CaLaGa2.34Al0.66O7 were grown from molten oxide mixtures and investigated by single crystal X-ray technique. Both compounds crystallize with tetragonal symmetry, space group D? P4 21m, (I): a = 7.8075; c = 5.1564 Å, (II): a = 7.9130, c = 5.2360 Å, Z = 2 and are isostructural with the Melilites. The crystal structure is discussed. 相似文献
7.
8.
张文 李宁蒋玲 缪巍林镇辉 姚骑均史生才陈健 吴培亨S.I.Svechnikov Yu. B. Vachtomin S. V. Antipov B. M. voronov G. N. Gol'tsman 《中国物理快报》2007,24(6):1778-1781
A quasi-optical superconducting NbN hot-electron bolometer (HEB) mixer is measured in the frequency range of 0.5-2.5 THz for understanding of the frequency dependence of noise temperature of THz coherent detectors. It has been found that noise temperature increasing with frequency is mainly due to the coupling loss between the quasioptical planar antenna and the superconducting HEB bridge when taking account of non-uniform distribution of high-frequency current. With the coupling loss corrected, the superconducting HEB mixer demonstrates a noise temperature nearly independent of frequency. 相似文献
9.
10.
Kochetkova A. S. Sosnov E. A. Malkov A. A. Antipov V. V. Kulikov N. A. Malygin A. A. 《Russian Journal of Applied Chemistry》2019,92(7):883-892
Russian Journal of Applied Chemistry - Effect of a simultaneous thermal treatment at 480°C and X-ray radiation (irradiation dose 10?3 C/kg (~4 R) in a vacuum (residual pressure... 相似文献