全文获取类型
收费全文 | 123篇 |
免费 | 5篇 |
专业分类
化学 | 75篇 |
晶体学 | 1篇 |
力学 | 1篇 |
数学 | 2篇 |
物理学 | 49篇 |
出版年
2024年 | 1篇 |
2021年 | 1篇 |
2019年 | 2篇 |
2018年 | 2篇 |
2017年 | 1篇 |
2016年 | 6篇 |
2015年 | 1篇 |
2014年 | 1篇 |
2013年 | 10篇 |
2012年 | 5篇 |
2011年 | 7篇 |
2010年 | 7篇 |
2009年 | 1篇 |
2008年 | 9篇 |
2007年 | 13篇 |
2006年 | 8篇 |
2005年 | 12篇 |
2004年 | 11篇 |
2003年 | 6篇 |
2002年 | 4篇 |
2001年 | 2篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1987年 | 2篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1973年 | 2篇 |
1971年 | 1篇 |
排序方式: 共有128条查询结果,搜索用时 31 毫秒
51.
52.
53.
Toru Matsui Takashi Togari Satoru Misawa Tomoyuki Namihira Naoya Shinzato Hitoshi Matsuda Seigo Sato 《Applied biochemistry and biotechnology》2010,162(3):823-829
Temperature shift cultivations with amino acid supplementation were optimized to produce porcine adenylate kinase (ADK) in
recombinant Escherichia coli harboring a pUC-based recombinant plasmid under the control of the trp promoter. With regard to temperature control, the culture condition was initially maintained at 35 °C for cellular growth,
but ADK expression was suppressed until the late logarithmic growth phase; subsequently, a temperature shift was applied (from
35 °C to 42 °C), which resulted in maximal ADK production. In addition, supplementation of amino acids, especially valine
and leucine, during the temperature shift stimulated ADK expression from 3.5% to 9.2% and 8.6% of the total protein, respectively.
After optimization, 1 g ADK per liter was produced within 16 h of cultivation with a dry cell weight of 21.8 g/l. In this
system, there was no loss of the recombinant plasmid during cultivation without selective pressure. 相似文献
54.
Kuang D Wang P Ito S Zakeeruddin SM Grätzel M 《Journal of the American Chemical Society》2006,128(24):7732-7733
A stable dye-sensitized solar cell has been obtained based on a new binary ionic liquid electrolyte system containing 1-propyl-3-methylimidazolium iodide and 1-ethyl-3-methylimidazolium tetracyanoborate. 相似文献
55.
The monomer and configurational sequences of several radical copolymers between substituted styrenes and acrylates have been examined by analyzing the high-resolution NMR spectra with the previously reported treatment of the styrene-methyl methacrylate system. The analyses have led to the conclusion that the monomer sequence distribution is just as expected from the usual copolymerization theory with r 1 and r 2. 相似文献
56.
Masafumi Shimizu Michihisa Yamamoto Michael Stopa Motonari Honda Seigo Tarucha 《Physica E: Low-dimensional Systems and Nanostructures》2005,26(1-4):460
We measure the Coulomb drag between parallel split-gate quantum wires with a quantum dot embedded in one of the two wires (drive wire). We observe negative Coulomb drag when a Coulomb oscillation peak appears in the drive wire and the conductance of the other wire (drag wire) is slightly below the first plateau. This indicates that correlation holes are dragged in the drag wire by single electron tunneling through the quantum dot in the drive wire. The drag is only promoted in the drag wire near the barrier regions of the dot, and low compressibility of the drag wire is necessary for the negative drag to occur. 相似文献
57.
T. Ota M. Stopa M. Rontani T. Hatano K. Yamada S. Tarucha H. Z. Song Y. Nakata T. Miyazawa T. Ohshima N. Yokoyama 《Superlattices and Microstructures》2003,34(3-6):159
Molecular states in a single pair of strongly coupled self-assembled InAs quantum dots are investigated using a sub-micron sized single-electron transistor containing just a few pairs of coupled InAs dots embedded in a GaAs matrix. We observe a series of well-formed Coulomb diamonds with charging energy of less than 5 meV, which are much smaller than those reported previously. This is because electrons are occupied in molecular states, which are spread over both dots and occupy a large volume. In the measurement of ground and excited state single-electron transport spectra with a magnetic field, we find that the electrons are sequentially trapped in symmetric and anti-symmetric states. This result is well explained by numerical calculation using an exact diagonalization method. 相似文献
58.
Aharonov-Bohm (AB) oscillations are studied for a parallel-coupled vertical double quantum dot with a common source and drain electrode. We observe AB oscillations of current via a one-electron bonding state as the ground state and an antibonding state as the excited state. As the center gate voltage becomes more negative, the oscillation period is clearly halved for both the bonding and antibonding states, and the phase changes by half a period for the antibonding state. This result can be explained by a calculation that takes account of the indirect interdot coupling via the two electrodes. 相似文献
59.
Yulia Ilina Christian Lorent Sagie Katz Jae‐Hun Jeoung Seigo Shima Marius Horch Ingo Zebger Holger Dobbek 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(51):18883-18887
[NiFe] hydrogenases are complex model enzymes for the reversible cleavage of dihydrogen (H2). However, structural determinants of efficient H2 binding to their [NiFe] active site are not properly understood. Here, we present crystallographic and vibrational‐spectroscopic insights into the unexplored structure of the H2‐binding [NiFe] intermediate. Using an F420‐reducing [NiFe]‐hydrogenase from Methanosarcina barkeri as a model enzyme, we show that the protein backbone provides a strained chelating scaffold that tunes the [NiFe] active site for efficient H2 binding and conversion. The protein matrix also directs H2 diffusion to the [NiFe] site via two gas channels and allows the distribution of electrons between functional protomers through a subunit‐bridging FeS cluster. Our findings emphasize the relevance of an atypical Ni coordination, thereby providing a blueprint for the design of bio‐inspired H2‐conversion catalysts. 相似文献
60.