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651.
Artur Czumaj Friedhelm Meyer auf der Heide Volker Stemann 《Information and Computation》1997,137(2):103
We consider randomized simulations of shared memory on a distributed memory machine (DMM) where thenprocessors and thenmemory modules of the DMM are connected via a reconfigurable architecture. We first present a randomized simulation of a CRCW PRAM on a reconfigurable DMM having a complete reconfigurable interconnection. It guarantees delay (log *n), with high probability. Next we study a reconfigurable mesh DMM (RM-DMM). Here thenprocessors andnmodules are connected via ann×nreconfigurable mesh. It was already known that ann×mreconfigurable mesh can simulate in constant time ann-processor CRCW PRAM with shared memory of sizem. In this paper we present a randomized step by step simulation of a CRCW PRAM with arbitrarily large shared memory on an RM-DMM. It guarantees constant delay with high probability, i.e., it simulates in real time. Finally we prove a lower bound showing that sizeΩ(n2) for the reconfigurable mesh is necessary for real time simulations. 相似文献
652.
Pedro Couto Aranzazu Jurio Artur Varej?o Miguel Pagola Humberto Bustince Pedro Melo-Pinto 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2011,15(10):1937-1944
In this work, image segmentation is addressed as the starting point within a motion analysis methodology intended for rat
biomechanics behavior characterization. First, we propose a general segmentation framework that uses interval valued fuzzy
sets (IVFSs) to determine the optimal image threshold value. The amplitude values of the IVFSs are used for representing the
unknowledge/ignorance of an expert on determining whether a pixel belongs to the background or to the object of the image.
Then, we introduce an extension of this methodology that uses a heuristic-based multi-threshold approach to determine the
optimal threshold. Experimental results are presented. 相似文献
653.
Lugmayr Artur Sutinen Erkki Suhonen Jarkko Sedano Carolina Islas Hlavacs Helmut Montero Calkin Suero 《Multimedia Tools and Applications》2017,76(14):15707-15733
Multimedia Tools and Applications - In human culture, storytelling is a long-established tradition. The reasons people tell stories are manifold: to entertain, to transfer knowledge between... 相似文献
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Light‐Induced Contraction/Expansion of 1D Photoswitchable Metallopolymer Monitored at the Solid–Liquid Interface 下载免费PDF全文
Mohamed El Garah Etienne Borré Artur Ciesielski Arezoo Dianat Rafael Gutierrez Gianaurelio Cuniberti Stéphane Bellemin‐Laponnaz Matteo Mauro Paolo Samorì 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(40)
The use of a bottom‐up approach to the fabrication of nanopatterned functional surfaces, which are capable to respond to external stimuli, is of great current interest. Herein, the preparation of light‐responsive, linear supramolecular metallopolymers constituted by the ideally infinite repetition of a ditopic ligand bearing an azoaryl moiety and Co(II) coordination nodes is described. The supramolecular polymerization process is followed by optical spectroscopy in dimethylformamide solution. Noteworthy, a submolecularly resolved scanning tunneling microscopy (STM) study of the in situ reversible trans‐to‐cis photoisomerization of a photoswitchable metallopolymer that self‐assembles into 2D crystalline patterns onto a highly oriented pyrolytic graphite surface is achieved for the first time. The STM analysis of the nanopatterned surfaces is corroborated by modeling the physisorbed species onto a graphene slab before and after irradiation by means of density functional theory calculation. Significantly, switching of the monolayers consisting of supramolecular Co(II) metallopolymer bearing trans‐azoaryl units to a novel pattern based on cis isomers can be triggered by UV light and reversed back to the trans conformer by using visible light, thereby restoring the trans‐based supramolecular 2D packing. These findings represent a step forward toward the design and preparation of photoresponsive “smart” surfaces organized with an atomic precision. 相似文献
655.
Juanmei Duan Phanish Chava Mahdi Ghorbani-Asl Denise Erb Liang Hu Arkady V. Krasheninnikov Harald Schneider Lars Rebohle Artur Erbe Manfred Helm Yu-Jia Zeng Shengqiang Zhou Slawomir Prucnal 《Advanced functional materials》2021,31(40):2104960
Trions, quasi-particles consisting of two electrons combined with one hole or of two holes with one electron, have recently been observed in transition metal dichalcogenides (TMDCs) and drawn increasing attention due to potential applications of these materials in light-emitting diodes, valleytronic devices as well as for being a testbed for understanding many-body phenomena. Therefore, it is important to enhance the trion emission and its stability. In this study, a MoSe2/FePS3 van der Waals heterostructure (vdWH) with type-I band alignment is constructed, which allows for carriers injection from FePS3 to MoSe2. At low temperatures, the neutral exciton (X0) emission in this vdWH is almost completely suppressed. The ITrion/Ix0 intensity ratio increases from 0.44 in a single MoSe2 monolayer to 20 in this heterostructure with the trion charging state changing from negative in the monolayer to positive in the heterostructure. The optical pumping with circularly polarized light shows a 14% polarization for the trion emission in MoSe2/FePS3. Moreover, forming such type-I vdWH also gives rise to a 20-fold enhancement of the room temperature photoluminescence from monolayer MoSe2. These results demonstrate a novel approach to convert excitons to trions in monolayer 2D TMDCs via interlayer doping effect using type-I band alignment in vdWH. 相似文献
656.
Dawid Pakulski Wodzimierz Czepa Stefano Del Buffa Artur Ciesielski Paolo Samorì 《Advanced functional materials》2020,30(2)
Membrane‐based processes, namely, water purification and harvesting of osmotic power deriving from the difference in salinity between seawater and freshwater are two strategic research fields holding great promise for overcoming critical global issues such as the world growing energy demand, climate change, and access to clean water. Ultrathin membranes based on 2D materials (2DMs) are particularly suitable for highly selective separation of ions and effective generation of blue energy because of their unique physicochemical properties and novel transport mechanisms occurring at the nano‐ and sub‐nanometer length scale. However, due to the relatively high costs of fabrication compared to traditional porous membrane materials, their technological transfer toward large‐scale applications still remains a great challenge. Herein, the authors present an overview of the current state‐of‐the‐art in the development of ultrathin membranes based on 2DMs for osmotic power generation and water purification. The authors discuss several synthetic routes to produce atomically thin membranes with controlled porosity and describe in detail their performance, with a particular emphasis on pressure‐retarded osmosis and reversed electrodialysis methods. In the last section, an outlook and current limitations as well as viable future developments in the field of 2DM membranes are provided. 相似文献
657.
Małgorzata Karpińska-Krakowiak Artur Modliński 《Journal of Computer Information Systems》2018,58(3):282-290
Practical jokes belong to the category of disparagement humor and they have been extensively investigated by social scientists for decades. Nevertheless, the available empirical results pertain mostly to human-to-human situations and little is known on the effects of pranks in the computer-mediated environment (CME). As CME encourages different patterns of reactions and behaviors than non-CME, the present study provides an experimental evaluation of consumer responses to brands that use practical jokes in their social media communication. The results reveal that high-disparagement pranks may significantly hurt brand perceptions and decrease brand affect. This effect is better predicted by prior brand attitudes than usage (i.e., the more favorable predisposition to a brand, the higher probability that a high-disparagement prank will produce a lower brand affect). No significant impact of low-disparagement pranks was found on subsequent brand responses. The findings will help scholars and practitioners in understanding this new phenomenon and in maximizing returns from humor online. 相似文献
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