全文获取类型
收费全文 | 294篇 |
免费 | 12篇 |
专业分类
电工技术 | 11篇 |
化学工业 | 116篇 |
金属工艺 | 2篇 |
机械仪表 | 13篇 |
建筑科学 | 14篇 |
能源动力 | 9篇 |
轻工业 | 24篇 |
水利工程 | 7篇 |
无线电 | 8篇 |
一般工业技术 | 36篇 |
冶金工业 | 11篇 |
原子能技术 | 3篇 |
自动化技术 | 52篇 |
出版年
2024年 | 2篇 |
2022年 | 30篇 |
2021年 | 33篇 |
2020年 | 15篇 |
2019年 | 9篇 |
2018年 | 13篇 |
2017年 | 11篇 |
2016年 | 9篇 |
2015年 | 9篇 |
2014年 | 8篇 |
2013年 | 16篇 |
2012年 | 16篇 |
2011年 | 25篇 |
2010年 | 12篇 |
2009年 | 9篇 |
2008年 | 13篇 |
2007年 | 19篇 |
2006年 | 9篇 |
2005年 | 6篇 |
2004年 | 5篇 |
2003年 | 3篇 |
2002年 | 5篇 |
2001年 | 6篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 5篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1989年 | 1篇 |
1985年 | 1篇 |
1982年 | 1篇 |
排序方式: 共有306条查询结果,搜索用时 31 毫秒
71.
Katiuscia Dallaglio Tiziana Petrachi Alessandra Marconi Francesca Truzzi Roberta Lotti Annalisa Saltari Paolo Morandi Mario Puviani Antonino Maiorana Dennis R. Roop Carlo Pincelli 《International journal of molecular sciences》2013,14(10):19540-19555
In human epidermis, keratinocyte stem cells (KSC) are characterized by high levels of β1-integrin, resulting in the rapid adhesion to type IV collagen. Since epithelial tumors originate from KSC, we evaluated the features of rapidly adhering (RAD) keratinocytes derived from primary human squamous cell carcinoma of the skin (cSCC). RAD cells expressed higher levels of survivin, a KSC marker, as compared to non-rapidly adhering (NRAD) cells. Moreover, RAD cells proliferated to a greater extent and were more efficient in forming colonies than NRAD cells. RAD cells also migrated significantly better than NRAD cells. When seeded in a silicone chamber and grafted onto the back skin of NOD SCID mice, RAD cells formed tumors 2–4 fold bigger than those derived from NRAD cells. In tumors derived from RAD cells, the mitotic index was significantly higher than in those derived from NRAD cells, while Ki-67 and survivin expression were more pronounced in RAD tumors. This study suggests that SCC RAD stem cells play a critical role in the formation and development of epithelial tumors. 相似文献
72.
Roberto Baldoni Ricardo Jiménez-Peris Marta Patiño-Martínez Leonardo Querzoni Antonino Virgillito 《Journal of Parallel and Distributed Computing》2008
Peer-to-peer systems (P2P) have become a popular technique to design large-scale distributed applications in unmanaged inter-domain settings, such as file sharing or chat systems, thanks to their capabilities to self-organize and evenly split the load among peers. Recently, enterprises owning a large IT hardware and software infrastructure started looking at these P2P technologies as a means both to reduce costs and to help their technical divisions to manage huge number of devices characterized by a high level of cooperation and a relatively low churn. Gaining a quick exclusive access to the system for maintenance or auditing purposes in these enterprise infrastructures is a fundamental operation to be implemented. Conversely, this kind of operation is usually not an issue in the previously mentioned inter-domain setting, where peers are inherently independent and cannot be managed. 相似文献
73.
Costantino Del Gaudio Giorgio Antonino Licciardi 《Fullerenes, Nanotubes and Carbon Nanostructures》2019,27(5):446-452
An effective filler dispersion within a polymeric matrix is known to be a crucial requirement for obtaining the desired performance from a composite. A quantification of this parameter cannot be always easily achieved and several methodologies have been proposed so far, generally based on complex image processing algorithms. However, no standard has been established yet.
In order to contribute to the quantitative evaluation of the filler dispersion in a polymeric matrix, a novel straightforward two-dimensional alternative method based on the analysis of electron microscopy micrographs is here proposed. Several case studies were considered to test the reliability of the approach, providing as resulting output, either a qualitative polar plot representative of the analyzed image and an index to measure the filler dispersion. 相似文献
74.
Silvio Barbarelli Gaetano Florio Mario Amelio Nino Michele Scomaienchi Antonino Cutrupi ManuelSanchez Blanco Giacomo Lo Zupone 《能源与动力工程:英文版》2014,(3):476-486
Tidal currents are a resource of great potentiality and not yet fully explored. Several efforts have been made to exploit these resources, but the costs associated to the deployment of tidal plants in marine environments are usually too high. The aim of this work is to present a system able to handle with the above mentioned problems, through the development of a particular hydrokinetic turbine design. In previous works, the authors described a basic turbine configuration achieving interesting performances, although some operational inconveniences were detected. Those problems have been existing so the solution should be optimized and redesigned. As a result, a new design of the turbine is proposed, consisting of a double rotor spinning in opposite directions in order to balance the induced mechanical torque. From preliminary evaluations related to the Messina Strait tidal cycles (Punta Pezzo site, RC, Italy), a single 12 m diameter turbine can supply a power of about 500 kW with a peak current speed of 3 m/s and deliver up to 450 MWh/year. 相似文献
75.
Rosanna Migliore Matteo Scala Anna Napoli Antonino Messina 《Journal of Engineering Mathematics》2013,82(1):187-197
A microscopic master equation describing the dynamics of two qubits coupled via a nonlinear mediator is constructed supposing that the two qubits, as well as the nonlinear mode, interact, each with its own independent bosonic bath. Generally speaking the master equation derived in this way represents a more appropriate tool for studying the dynamics of open quantum systems. Indeed we show that it is more complex than the phenomenological master equation, constructed simply adding ad hoc dissipative terms. 相似文献
76.
Pietro Paolo Corso Antonino Di Piazza Emilio Fiordilino Leonardo Lo Cascio Franco Persico 《Journal of Modern Optics》2013,60(8):1373-1387
Abstract The electromagnetic spectrum emitted by a one-dimensional atom driven by a strong laser field is obtained by use of the acceleration form and interpreted by means of few general properties of the matrix elements of the acceleration operator. We show that the emission occurs essentially in a region near the atomic core where the acceleration is significant and we investigate the role of the various emission channels arising from interference effects between transitions involving the bare atomic levels. 相似文献
77.
78.
Maurizio Sansotera Walter Navarrini Giuseppe Resnati Pierangelo Metrangolo Antonino Famulari Claudia L. Bianchi P. Antonio Guarda 《Carbon》2010,48(15):4382-4390
Superhydrophobic conductive carbon blacks were prepared by covalent bonding of perfluorocarbon and perfluoropolyether chains on the conductive carbon black surface. Perfluorodiacyl and perfluoropolyether peroxides were used as reagents for the chemical treatment. Their thermal decomposition produced respectively, perfluoroalkyl and perfluoropolyether radicals that directly bonded the polycyclic aromatic structure of carbon black surface. Measurements of contact angles with water on molded pellets made with carbon black powder demonstrated that water droplets were enduringly stable on the treated carbon blacks. Contact angle values were significantly high, exceeding the superhydrophobicity threshold. On the contrary, the droplets were adsorbed in few seconds by the native carbon black. Conductivity measurements showed that the covalent linkage of fluorinated chains weakly modified the electrical properties of the conductive carbon black, even if the surface properties changed so deeply. The relationship between the linkage of fluorinated chains and the variations of physical–chemical properties were studied combining electron spectroscopy, resistivity measurements, X-ray diffraction, scanning electron microscopy, surface area analysis and thermal gravimetric analysis. The superhydrophobic conductive carbon blacks were compared with a superhydrophobic carbon black obtained by direct fluorination of conductive carbon black with elemental fluorine, F2. 相似文献
79.
Giuseppe Giambanco Giuseppe Fileccia Scimemi Antonino Spada 《Computational Mechanics》2012,50(3):353-366
Mesomodelling of structures made of heterogeneous materials requires the introduction of mechanical models which are able to simulate the interactions between the adherents. Among these devices is quite popular the zero thickness interface (ZTI) model where the contact tractions and the displacement discontinuities are the primary static and kinematic variables. In some cases the joint response depends also on the internal stresses and strains within the thin layer adjacent to the joint interfaces. The interphase model, taking into account these additional variables, represents a sort of enhanced ZTI. In this paper a general theoretical formulation of the interphase model is reported and an original finite element, suitable for two-dimensional applications, is presented. A simple numerical experiment in plane stress state condition shows the relevant capabilities of the interphase element and allows to investigate its numerical performance. Some defects related to the shear locking of the element are resolved making use of well known numerical strategies. Finally, further numerical application to masonry structures are developed. 相似文献
80.
Gabriele La Monica Antonino Lauria Alessia Bono Annamaria Martorana 《International journal of molecular sciences》2021,22(11)
The approval of the first HIV-1 protease inhibitors (HIV-1 PRIs) marked a fundamental step in the control of AIDS, and this class of agents still represents the mainstay therapy for this illness. Despite the undisputed benefits, the necessary lifelong treatment led to numerous severe side-effects (metabolic syndrome, hepatotoxicity, diabetes, etc.). The HIV-1 PRIs are capable of interacting with “secondary” targets (off-targets) characterized by different biological activities from that of HIV-1 protease. In this scenario, the in-silico techniques undoubtedly contributed to the design of new small molecules with well-fitting selectivity against the main target, analyzing possible undesirable interactions that are already in the early stages of the research process. The present work is focused on a new mixed-hierarchical, ligand-structure-based protocol, which is centered on an on/off-target approach, to identify the new selective inhibitors of HIV-1 PR. The use of the well-established, ligand-based tools available in the DRUDIT web platform, in combination with a conventional, structure-based molecular docking process, permitted to fast screen a large database of active molecules and to select a set of structure with optimal on/off-target profiles. Therefore, the method exposed herein, could represent a reliable help in the research of new selective targeted small molecules, permitting to design new agents without undesirable interactions. 相似文献