全文获取类型
收费全文 | 744篇 |
免费 | 20篇 |
国内免费 | 6篇 |
专业分类
化学 | 475篇 |
晶体学 | 17篇 |
力学 | 12篇 |
数学 | 36篇 |
物理学 | 230篇 |
出版年
2023年 | 5篇 |
2021年 | 9篇 |
2020年 | 9篇 |
2019年 | 8篇 |
2018年 | 6篇 |
2017年 | 6篇 |
2016年 | 14篇 |
2015年 | 15篇 |
2014年 | 17篇 |
2013年 | 47篇 |
2012年 | 44篇 |
2011年 | 33篇 |
2010年 | 30篇 |
2009年 | 28篇 |
2008年 | 37篇 |
2007年 | 52篇 |
2006年 | 36篇 |
2005年 | 23篇 |
2004年 | 33篇 |
2003年 | 25篇 |
2002年 | 24篇 |
2001年 | 28篇 |
2000年 | 11篇 |
1999年 | 17篇 |
1997年 | 7篇 |
1996年 | 8篇 |
1995年 | 6篇 |
1994年 | 10篇 |
1993年 | 11篇 |
1992年 | 14篇 |
1991年 | 6篇 |
1990年 | 11篇 |
1989年 | 8篇 |
1988年 | 4篇 |
1987年 | 11篇 |
1986年 | 8篇 |
1985年 | 17篇 |
1984年 | 9篇 |
1983年 | 11篇 |
1982年 | 6篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1979年 | 12篇 |
1978年 | 9篇 |
1977年 | 4篇 |
1976年 | 6篇 |
1975年 | 5篇 |
1974年 | 5篇 |
1973年 | 7篇 |
1967年 | 4篇 |
排序方式: 共有770条查询结果,搜索用时 15 毫秒
111.
Chen Y Pai A Somiya K Kawamura S Sato S Kokeyama K Ward RL Goda K Mikhailov EE 《Physical review letters》2006,97(15):151103
We propose a class of displacement- and laser-noise-free gravitational-wave-interferometer configurations, which does not sense nongeodesic mirror motion and laser noise, but provides a nonvanishing gravitational-wave signal. Our interferometers consist of four mirrors and two beam splitters, which form four Mach-Zehnder interferometers. By contrast to previous works, no composite mirrors with multiple reflective surfaces are required. Each mirror in our configuration is sensed redundantly, by at least two pairs of incident and reflected beams. Displacement- and laser-noise-free detection is achieved when output signals from these four interferometers are combined appropriately. Our 3-dimensional interferometer configuration has a low-frequency response proportional to f2, which is better than the f3 achievable by previous 2-dimensional configurations. 相似文献
112.
Yoshikawa M Kawamura K Ejima A Aoki T Sakurai S Hayashi K Watanabe K 《Macromolecular bioscience》2006,6(3):210-215
Novel molecular recognition materials were prepared from water soluble proteins from thermophile G. thermodenitrificans DSM465 by an alternative molecular imprinting method. Water soluble proteins from G. thermodenitrificans DSM465 were converted into the molecularly imprinted materials by adopting 9-EA as a print molecule. The molecularly imprinted protein membranes recognized As in preference to Gs. The adsorption isotherms led to the conclusion that molecular recognition sites toward As were constructed by the presence of 9-EA during the membrane preparation process. The affinity constant between As and the molecular recognition site thus constructed was determined to be 1.75 x 10(5) mol(-1) dm(3). The results obtained in the present study suggest that water soluble proteins from G. thermodenitrificans DSM465 is one of environmentally-friendly 'green' polymers to be converted into molecular recognition materials by applying an alternative molecular imprinting method. 相似文献
113.
114.
T. Nagatomo H. Ueno M. Mihara K. Matsuta A. Yoshimi Y. Ichikawa K. Yamada H. Kawamura A. Ozawa T. Moriguchi Y. Ishibashi K. Asahi M. Uchida K. Suzuki T. Inoue Y. Hasama H. Iijima T. Sumikama M. Fukuda T. Minamisono 《Hyperfine Interactions》2010,198(1-3):103-107
Electric quadrupole coupling constant eqQ/h of the extremely proton-rich 23Al (I π ?=?5/2?+?, T 1/2?=?0.47 s) nucleus implanted into an Al2O3 single crystal has been measured for the first time, using the β-ray detecting nuclear quadrupole resonance method (β-NQR) in a high magnetic field. As a preliminary result, the quadrupole coupling constant was determined as |eqQ/h(23Al) |?=?2.66±0.77 MHz. Using the quadrupole coupling constant of 27Al in Al2O3 as a reference, the Q moment of the ground state of 23Al was extracted as |Q(23Al)|?~?160 mb, which is well explained by the shell model calculation in the sd-shell model space with the USD interaction. 相似文献
115.
Pieter C. Allaart Kiko Kawamura 《Journal of Mathematical Analysis and Applications》2010,372(2):656-1129
Let T be Takagi's continuous but nowhere-differentiable function. Using a representation in terms of Rademacher series due to N. Kono [Acta Math. Hungar. 49 (1987) 315-324], we give a complete characterization of those points where T has a left-sided, right-sided, or two-sided infinite derivative. This characterization is illustrated by several examples. A consequence of the main result is that the sets of points where T′(x)=±∞ have Hausdorff dimension one. As a byproduct of the method of proof, some exact results concerning the modulus of continuity of T are also obtained. 相似文献
116.
Kazuhiro Kawamura 《Discrete Mathematics》2010,310(15-16):2204-2211
117.
We study a depinning transition based on transient dynamics of vortices driven by a suddenly applied dc current, focusing on whether a difference in the equilibrium vortex phase that can lead to a different vortex flow will change the critical behavior. After preparing an ordered initial vortex configuration, we measure the time evolution of voltage associated with dynamic disordering in three magnetic fields, corresponding to the ordered phase (OP), disordered phase (DP), and coexistence phase. The critical behavior of the depinning transition is commonly observed in these phases, pointing to the universality of the transition. However, the critical behavior is most marked in the coexistence phase, while the suppression of the critical region and that of dynamic disordering are observed in OP and DP, respectively, whose origin is attributed to the different flow states among these phases. 相似文献
118.
Yoshida Go Ninomiya Kazuhiko Inagaki Makoto Higemoto Wataru Strasser Patrick Kawamura Naritoshi Shimomura Koichiro Miyake Yasuhiro Miura Taichi Kubo Kenya M. Shinohara Atsushi 《Journal of Radioanalytical and Nuclear Chemistry》2019,320(2):283-289
The role of valence electrons for the muon capture process by molecules is experimentally investigated with the aid of cascade calculations. Low-momentum muons are introduced to gas targets of CO, CO2, and COS below atmospheric pressure. The initial states of captured muons are determined from the measured muonic X-ray structure of the Lyman and Balmer series. We propose that the lone pair electrons in the carbon atom of CO significantly contribute to the capture of a muon with large angular momenta.
相似文献119.
Mussenbrock T Brinkmann RP Lieberman MA Lichtenberg AJ Kawamura E 《Physical review letters》2008,101(8):085004
In low-pressure capacitive radio frequency discharges, two mechanisms of electron heating are dominant: (i) Ohmic heating due to collisions of electrons with neutrals of the background gas and (ii) stochastic heating due to momentum transfer from the oscillating boundary sheath. In this work we show by means of a nonlinear global model that the self-excitation of the plasma series resonance which arises in asymmetric capacitive discharges due to nonlinear interaction of plasma bulk and sheath significantly affects both Ohmic heating and stochastic heating. We observe that the series resonance effect increases the dissipation by factors of 2-5. We conclude that the nonlinear plasma dynamics should be taken into account in order to describe quantitatively correct electron heating in asymmetric capacitive radio frequency discharges. 相似文献
120.
Highly Efficient Dehydrogenative Coupling of Hydrosilanes with Amines or Amides Using Supported Gold Nanoparticles 下载免费PDF全文
Dr. Takato Mitsudome Teppei Urayama Dr. Zen Maeno Dr. Tomoo Mizugaki Prof. Dr. Koichiro Jitsukawa Prof. Dr. Kiyotomi Kaneda 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(8):3202-3205
Hydroxyapatite‐supported gold nanoparticles (Au/HAP) can act as a highly active and reusable catalyst for the coupling of hydrosilanes with amines under mild conditions. Various silylamines can be selectively obtained from diverse combinations of equimolar amounts of hydrosilanes with amines including less reactive bulky hydrosilanes. This study also highlights the applicability of Au/HAP to the selective synthesis of silylamides through the coupling of hydrosilanes with amides, demonstrating the first example of an efficient heterogeneous catalyst. Moreover, Au/HAP shows high reusability and applicability for gram‐scale synthesis. 相似文献