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71.
Facile Preparation of Multifunctional WS2/WOx Nanodots for Chelator‐Free 89Zr‐Labeling and In Vivo PET Imaging 下载免费PDF全文
Liang Cheng Anyanee Kamkaew Sida Shen Hector F. Valdovinos Haiyan Sun Reinier Hernandez Shreya Goel Teng Liu Cyrus R. Thompson Todd E. Barnhart Zhuang Liu Weibo Cai 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(41):5750-5758
While position emission tomography (PET) is an important molecular imaging technique for both preclinical research and clinical disease diagnosis/prognosis, chelator‐free radiolabeling has emerged as a promising alternative approach to label biomolecules or nanoprobes in a facile way. Herein, starting from bottom‐up synthesized WS2 nanoflakes, this study fabricates a unique type of WS2/WOx nanodots, which can function as inherent hard oxygen donor for stable radiolabeling with Zirconium‐89 isotope (89Zr). Upon simply mixing, 89Zr can be anchored on the surface of polyethylene glycol (PEG) modified WS2/WOx (WS2/WOx‐PEG) nanodots via a chelator‐free method with surprisingly high labeling yield and great stability. A higher degree of oxidation in the WS2/WOx‐PEG sample (WS2/WOx (0.4)) produces more electron pairs, which would be beneficial for chelator‐free labeling of 89Zr with higher yields, suggesting the importance of surface chemistry and particle composition to the efficiency of chelator‐free radiolabeling. Such 89Zr‐WS2/WOx (0.4)‐PEG nanodots are found to be an excellent PET contrast agent for in vivo imaging of tumors upon intravenous administration, or mapping of draining lymph nodes after local injection. 相似文献
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73.
Ensemble of surrogates 总被引:5,自引:3,他引:2
Tushar Goel Raphael T. Haftka Wei Shyy Nestor V. Queipo 《Structural and Multidisciplinary Optimization》2007,33(3):199-216
The custom in surrogate-based modeling of complex engineering problems is to fit one or more surrogate models and select the
one surrogate model that performs best. In this paper, we extend the utility of an ensemble of surrogates to (1) identify
regions of possible high errors at locations where predictions of surrogates widely differ, and (2) provide a more robust
approximation approach. We explore the possibility of using the best surrogate or a weighted average surrogate model instead
of individual surrogate models. The weights associated with each surrogate model are determined based on the errors in surrogates.
We demonstrate the advantages of an ensemble of surrogates using analytical problems and one engineering problem. We show
that for a single problem the choice of test surrogate can depend on the design of experiments. 相似文献
74.
Robots are frequently used for operations in hostile environments. The very nature of these environments, however, increases the likelihood of robot failures. Common failure-tolerance techniques rely on effective failure detection and identification. Since a failure may not always be successfully identified, or, even if identified, may not be identified soon enough, it becomes important to consider the behavior of manipulators with unidentified failures. This work investigates the behavior of robots experiencing unidentified locked-joint failures in a general class of tasks characterized by point-to-point motion. Based on the analysis, a procedure for workspace evaluation is developed that allows for the identification of regions in the manipulator's workspace in which tasks may be completed even with such failures. © 2005 Wiley Periodicals, Inc. 相似文献
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We describe an intracranial extra-axial petroclival schwannoma which did not arise from any cranial nerve, nor was it attached to brain parenchyma or dura. The possible pathogenesis is discussed. 相似文献
78.
Diltiazem, a calcium channel blocker, and a cardiovascular therapeutic agent offers significant protection to mice against lethal dose of ionizing radiation. Considering the potential efficacy of diltiazem as a radioprotector for human use, it was deemed necessary to investigate its influence on radiation-induced behavioural changes like nausea, vomiting, learning, memory and performance. In the present studies, conditioned taste aversion (CTA) test based on consumption of saccharin solution, was used as a marker of behavioural changes. Significant CTA (97 +/- 2%) was observed in rats irradiated with Co-60 gamma rays (absorbed dose 1 Gy). Administration of diltiazem at doses greater than 10 mg/kg, body wt, evoked CTA in a dose-dependent manner and that was found to be further aggravated on irradiation. At a lower dose of 5 mg/kg, body wt, diltiazem did not evoke CTA and protected against radiation induced aversion significantly (62 +/- 3%). The results suggest that diltiazem at concentrations lower than 10 mg/kg, body wt, in rats may be useful in preventing radiation induced behavioural changes. This observation could be of particular significance in clinical radiotherapy where radiation induced nausea and vomiting are of great concern. 相似文献
79.
Goel L. Lie T.T. Maswood A.I. Shrestha G.B. 《Power Systems, IEEE Transactions on》1996,11(3):1131-1138
This paper describes the main features of four design modules that form part of the curriculum for the final year power engineering students at the Nanyang Technological University, Singapore. Through the use of these modules, the students gain an insight into the various aspects of power engineering-including power electronics and drives-and this will hopefully help them in a better understanding of the practical aspects of power engineering, and therefore make them better engineers in the power industry. The four modules described are Generating Capacity Expansion Planning, Rectifier and DC Motor Control, Power Systems Operations Planning, and Security Enhancement using Optimal Power Flow 相似文献
80.
Sambasiva R. Bhatta Ashok K. Goel 《Engineering Applications of Artificial Intelligence》1996,9(6):601-609
Design is a wide-ranging and open-ended information-processing task in engineering; analogy is a very common method for addressing engineering design problems. Analogical design is the process of retrieving a known design (source analog) similar to the current design problem (target), and transferring parts of the structure of the known design to the current problem. The power of an analogical designer thus comes in part from the ability to retrieve the “right” design when a new problem is specified. Indexing of designs is therefore an important issue in analogical design. This issue, in fact, has three different aspects: (1) indexing vocabulary, (2) learning of the indices to a new design, and (3) use of the learned indices for retrieving stored designs. The authors of this paper have been exploring the hypothesis that teleologicall causal models of engineering designs give rise to the indexing vocabulary, enable and constrain the learning of indices for new designs, and provide similarity measures for matching a target problem with the stored design and retrieving relevant ones. This hypothesis has been tested in both interactive knowledge acquisition and autonomous design problem solving and learning, in engineering domains such as electrical circuits and heat exchangers. 相似文献