全文获取类型
收费全文 | 116篇 |
免费 | 1篇 |
专业分类
化学工业 | 25篇 |
机械仪表 | 1篇 |
建筑科学 | 6篇 |
能源动力 | 1篇 |
轻工业 | 12篇 |
无线电 | 26篇 |
一般工业技术 | 24篇 |
冶金工业 | 16篇 |
原子能技术 | 1篇 |
自动化技术 | 5篇 |
出版年
2023年 | 2篇 |
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 2篇 |
2019年 | 1篇 |
2014年 | 1篇 |
2013年 | 5篇 |
2012年 | 3篇 |
2011年 | 2篇 |
2010年 | 1篇 |
2009年 | 2篇 |
2008年 | 8篇 |
2007年 | 4篇 |
2006年 | 4篇 |
2005年 | 4篇 |
2004年 | 4篇 |
2003年 | 2篇 |
2002年 | 2篇 |
2001年 | 4篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1998年 | 9篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 6篇 |
1989年 | 2篇 |
1988年 | 6篇 |
1987年 | 1篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1984年 | 3篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1973年 | 2篇 |
1954年 | 2篇 |
排序方式: 共有117条查询结果,搜索用时 0 毫秒
1.
Dupont S. Beaurain A. Miska P. Zegaoui M. Vilcot J.-P. Li H.W. Constant M. Decoster D. Chazelas J. 《Electronics letters》2004,40(14):865-866
The fabrication and characterisation of low-loss InGaAsP/InP optical submicron waveguides made with ICP etching is reported. Their width ranges from 0.2 to 2 /spl mu/m. For the 0.5 /spl mu/m width, the propagation losses at /spl lambda/=1.55 /spl mu/m as low as 4.2 dB/mm have been measured. 相似文献
2.
Fabio Fais Reda Juskeviciene Veronica Francardo Stphanie Mateos Manuela Guyard Ccile Viollet Samuel Constant Massimo Borelli Ilja P. Hohenfeld 《International journal of molecular sciences》2022,23(7)
The nasal epithelium is a key portal for infection by respiratory viruses such as SARS-CoV-2 and represents an important target for prophylactic and therapeutic interventions. In the present study, we test the safety and efficacy of a newly developed nasal spray (AM-301, marketed as Bentrio) against infection by SARS-CoV-2 and its Delta variant on an in vitro 3D-model of the primary human nasal airway epithelium. Safety was assessed in assays for tight junction integrity, cytotoxicity and cilia beating frequency. Efficacy against SARS-CoV-2 infection was evaluated in pre-viral load and post-viral load application on airway epithelium. No toxic effects of AM-301 on the nasal epithelium were found. Prophylactic treatment with AM-301 significantly reduced viral titer vs. controls over 4 days, reaching a maximum reduction of 99% in case of infection from the wild-type SARS-CoV-2 variant and more than 83% in case of the Delta variant. When AM-301 administration was started 24 h after infection, viral titer was reduced by about 12-folds and 3-folds on Day 4. The results suggest that AM-301 is safe and significantly decelerates SARS-CoV-2 replication in cell culture inhibition assays of prophylaxis (pre-viral load application) and mitigation (post-viral load application). Its physical (non-pharmaceutical) mechanism of action, safety and efficacy warrant additional investigations both in vitro and in vivo for safety and efficacy against a broad spectrum of airborne viruses and allergens. 相似文献
3.
A nondestructive method is proposed to analyze the internal stresses of a circular bilayered laminate glassresin. It is based on the measurement by optical interferometry of small deformations of the laminate under the influence of temperature, time, or applied mechanical stresses of known value. For example, the stress induced by the curing of the thermosetting resin layer is determined and the postcuring relaxation of the stress is measured. Other possibilities or improvements of the method are indicated: The determination of the Young's modulus of the thermosetting resin as a function of time, the determination of the work-hardening rate, and the determination of the ultimate properties of the laminate are just a few of them. 相似文献
4.
Verhelst SH Michiels PJ van der Marel GA van Boeckel CA van Boom JH 《Chembiochem : a European journal of chemical biology》2004,5(7):937-942
Aminoglycoside antibiotics, which are able to selectively bind to RNA, are considered to be an important lead in RNA-targeting drug discovery. In this study, surface plasmon resonance (SPR) was employed to explore the interaction of aminoglycosides with known tobramycin-binding RNA hairpins (aptamers) and an unrelated RNA hairpin. It was established that aminoglycosides have multiple interactions with RNA hairpins. Unexpectedly, the different hairpins showed comparable affinity for a set of related aminoglycosides. The observed absence of selectivity presents an extra hurdle in the discovery of novel aminoglycosides as specific drugs that target defined RNA hairpins. 相似文献
5.
Daniela Reimer Dr. Kimberly N. Cowles Anna Proschak Friederike I. Nollmann Dr. Andrea J. Dowling Marcel Kaiser Prof. Dr. Richard ffrench‐ Constant Prof. Dr. Heidi Goodrich‐Blair Prof. Dr. Helge B. Bode 《Chembiochem : a European journal of chemical biology》2013,14(15):1991-1997
Six novel linear peptides, named “rhabdopeptides”, have been identified in the entomopathogenic bacterium Xenorhabdus nematophila after the discovery of the corresponding rdp gene cluster by using a promoter trap strategy for the detection of insect‐inducible genes. The structures of these rhabdopeptides were deduced from labeling experiments combined with detailed MS analysis. Detailed analysis of an rdp mutant revealed that these compounds participate in virulence towards insects and are produced upon bacterial infection of a suitable insect host. Furthermore, two additional rhabdopeptide derivatives produced by Xenorhabdus cabanillasii were isolated, these showed activity against insect hemocytes thereby confirming the virulence of this novel class of compounds. 相似文献
6.
Constant L. Ruiz P. Abel M. Robach Y. Porte L. Bertolini J.C. 《Topics in Catalysis》2000,14(1-4):125-129
The catalytic properties, with respect to the 1,3-butadiene hydrogenation reaction, of strained Pd films on Cu(110) (lattice mismatch 8%) has been probed as a function of the film thickness. The characterization of the adlayer has been made by the combined use of STM with LEED and AES. For deposits below 1015 Pd/cm2 (i.e., about 1 ML) the catalytic activity is near zero. This is the consequence of the formation of a Pd–Cu surface alloy with tendency for Cu to migrate/segregate to the surface. The catalytic activity suddenly increases to reach a maximum value for about 3 ML; the activity is then one order of magnitude higher than that of the pure Pd(110) surface. This is the consequence of the presence of a strained Pd overlayer, with Pd surface atoms having very unusual geometry, and hence very peculiar electronic and chemical properties. The catalytic activity then decreases as the Pd coverage is increased, and tends to values near that of the pure Pd(110). Gradual relaxation of the film geometry towards that of the normal fcc Pd structure probably exists. 相似文献
7.
8.
9.
Johannes Wippler Theo Fett Thomas Böhlke Michael J. Hoffmann 《Journal of the European Ceramic Society》2013,33(10):1729-1736
Silicon nitride is often used, when high fracture toughness and strength is needed. For a safe and economic structural design with this material, a prediction of its resistance against thermal and mechanical loads is important. The finite element method together with a continuum damage mechanics model allows for such calculations. The parameters of the suggested model have been adjusted to three-dimensional micromechanical finite element simulations, which include models for the microstructure, the thermoelasticity and the fracture. The material model is used for four-point bend test simulations. The results are compared to recent experiments. 相似文献
10.
S. Silvestre D. Bernard S. Mezi re E. Constant 《Materials Science and Engineering: B》2001,80(1-3):270-273
The results obtained, very recently, in n-type Si-doped GaAs passivated with a hydrogen (H) or deuterium (D) plasma, on the stability of the Si–H or Si–D complexes are summarized. It is shown that a strong dissociation of the Si–H or Si–D complexes, associated with a large isotope effect is observed when hot electrons are produced or externally injected (using an electron-beam) in Si-doped hydrogenated or deuterated GaAs. The application of these results to the reliability of III–V devices is studied. The role of hot electrons is described and the device lifetime improvement, which could be obtained by using suitable thermal annealings, is discussed. 相似文献