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61.
In order to assess how effective a combination of diagnostic methods, each addressing specific aetiopathogenic aspects, would be in uncovering the cause of common chronic nasal obstruction, we evaluated 45 consecutive adult subjects. They were submitted to rhinomanometry testing, sinus CT-scans and RASTs to prevalent allergens. Most, but not all, patients ended up showing abnormal results in at least one of the diagnostic procedures. Sinus pathology was, by far, the most frequent diagnosis, while allergy took second place, with a number of atopic subjects displaying sinusitis as well. On the other hand, septal deviations with a significant effect on nasal resistance were only seldom found to be the cause of chronic nasal obstruction. 相似文献
62.
Fusion cross-section data are presented as a function of center-of-mass energy for different reactions involving light and medium-light heavy-ion systems with compound atomic mass number between 18 and 80. The systems range from 6Li + 12C to 40Ca + 40Ca. The data are given for the region starting from slightly below the Coulomb barrier energy to about six to seven times its value, if they are available. This compilation is primarily to facilitate theoretical interpretation of experimental results. It also serves to give researchers an overview of the range and status of the data. Literature published up to June 1983 has been surveyed. 相似文献
63.
Surface characterization and catalysis can significantly benefit from the application of generalized two-dimensional (2D) correlation analysis. This two-dimensional approach allows a better resolution of overlapping peaks, can reveal new features not readily observable in the raw spectra, gives clear evidence for spectral intensities that change as an effect of a perturbation applied to the system, and allows the establishment of time sequences for the changes occurring in different spectral features of interest for determining reaction intermediates and/or mechanisms. The interpretation of the synchronous and asynchronous plots was observed to lead to erroneous time sequences when spectral features change in a non-monotonic way, such as a biphasic or oscillatory behavior, under the influence of a perturbation. We propose a new approach to the 2D correlation analysis to avoid misinterpretation of the results calculated in the asynchronous plot. Progressive correlation analysis (ProCorA) calculates the synchronous plot from the first two spectra of the data matrix and one spectrum is added at every step of the analysis. The sequence of changes can be set up from the progressive evolution of peaks in both the synchronous and asynchronous plots. 相似文献
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Goldenberg A.A. Trachtenberg J. Kucharczyk W. Yang Yi Haider M. Ma L. Weersink R. Raoufi C. 《Mechatronics, IEEE/ASME Transactions on》2008,13(3):374-379
This paper reports on the development of a new closed-bore magnetic resonance imaging (MRI) compatible robotic system for image-guided prostatic interventions: ablation, brachytherapy, and biopsy. The first stage of development addresses only laser-based ablation. The robot actuators are ultrasonic motors. The first physical robot prototype was manufactured and tested in the MRI with an ablation tool. The tests covered magnetic resonance (MR) compatibility, tool visualization, and robot control accuracy. Robot tip position error is less than 2 mm at points closer than 0.5 m to the isocenter. A method to control ultrasonic motors for MRI-compatibility is reported. 相似文献
66.
Haris Mahmood Khan Chaudhry Haider Ali Tanveer Iqbal Saima Yasin Muhammad Sulaiman Hamayoun Mahmood Muhammad Raashid Mohsin Pasha Bozhong Mu 《中国化学工程学报》2019,27(10):2238-2250
Biodiesel utilization has been rapidly growing worldwide as the prime alternative to petrodiesel due to a global rise in diesel fuel demand along with hazardous emissions during its thermochemical conversion. Although, several debatable issues including feedstock availability and price, fuel and food competition, changes in land use and greenhouse gas emission have been raised by using edible as well as inedible feedstocks for the production of biodiesel. However, non-crop feedstocks could be a promising alternative. In this article, waste cooking oils have been recommended as a suitable option for biodiesel production bearing in mind the current national situation. The important factors such as the quantity of waste cooking oil produced, crude oil and vegetable oil import expenses, high-speed diesel imports, waste management issues and environmental hazards are considered. Moreover, process simulation and operating cost evaluation of an acid catalyzed biodiesel production unit are also conducted. The simulation results show that the production cost of waste cooking oil-based biodiesel is about 0.66USD·L-1. We believe that the present overview would open new pathways and ideas for the development of biofuels from waste to energy approach in Pakistan. 相似文献
67.
Joo W. Cangussu Syed W. Haider Kendra Cooper Michael Baron 《Software Testing, Verification and Reliability》2011,21(2):125-152
Estimating the number of defects in a software product is an important and challenging problem. A multitude of estimation techniques have been proposed for defect prediction. However, not all techniques are applicable in all cases. The selection of the proper approach to use depends on multiple factors: the features of the approach; the availability of resources; and the goals for using the estimated defect data. In this paper a survey of existing estimation techniques and a decision support approach for selecting the most suitable defect estimation technique for a project, with specific goals, is proposed. The results of the ranking are a clear indication that no estimation technique provides a single, comprehensive solution; the selection must be done according to a given scenario. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
68.
Pankul Goel Noor Zaman Khan Zahid A. Khan Abdulrahman Ahmari Namrata Gangil Mustufa Haider Abidi 《Materials and Manufacturing Processes》2019,34(2):192-200
AA7xxx and AISI304 stainless steel (SS) are employed in promising applications. Al alloy-to-SS dissimilar joining is difficult and challenging. Major challenge in the joining of these alloys is the difficulty in mixing of these materials which possess exotic and widely distant properties. AA7475-T761 is a high strength aluminum alloy which is used in key aircraft components. Maiden AA7475-T761 and AISI304 dissimilar joints were fabricated using friction stir welding. Welding was performed with tool having pin diameter of 4 mm and offset of 1.25 mm on Aluminum side. Tool rotational speed, traverse speed and shoulder diameter were varied in the range of 450–560 rpm, 50–63 mm/min, and 12–14 mm, respectively. Mechanical tests showed that joint formed with 14 mm diameter, 560 rpm and 50 mm/min gave the best joint efficiency of 71% of Al-alloy at 7.31% elongation. The materials mixing issues during processing were analyzed with SEM mircrostructure and fractography. Metallography also revealed that offset is critical to the success of joint as it controlled effective mixing of SS and Al in 15 and 85 vol.%, respectively. SS fragments from thermo-mechanically affected zone of SS were found to be partially sheared forming layer of thickness equal to tool traverse/revolution ratio. 相似文献
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