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991.
ME Reilly D Mantle PJ Richardson J Salisbury J Jones TJ Peters VR Preedy 《Canadian Metallurgical Quarterly》1997,21(5):792-798
The complexity of the spot patterns of two-dimensional electrophoresis gels made it necessary to use image processing techniques to analyze the gels. An important issue in the analysis is the detection and quantification of the protein spots. In this paper we describe a new technique to segment and model the different spots. For the segmentation of a gel into its different spot regions we apply a watershed technique, which is robust and efficient. For the quantification of the spots, a new spot model is constructed, based on diffusion principles. Besides the advantage of having a physical interpretation, the model is demonstrated to be superior to the commonly used Gaussian models. 相似文献
992.
Katherine Jones 《International Journal of Network Management》1995,5(2):77-81
When a disaster recovery plan (DRP) is in place in a company, it is often solely for the mainframe; too often no attention is paid to the departmental distributed servers. 相似文献
993.
994.
995.
D. B. Hawthorne R. D. Jones P. A. Barrbett T. E. Kavanagh B. J. Clarke 《Journal of the Institute of Brewing》1986,92(2):181-184
Methods have been developed for the analysis of C4 to C10 fatty acids in beer, wort and carbohydrate syrups. The methods are based on the adsorption of the aqueous samples on to solid supports followed by removal of the fatty acids with organic solvents. The methods are suitable for routine batchwise analysis of fatty acids and the reproducibility of the analysis and recoveries of the acids are generally good. Problems often encountered with analysis of C4 to C10 fatty acids and possible solutions are also discussed. 相似文献
996.
Novel, wide bandwidth, micromachined ultrasonic transducers 总被引:1,自引:0,他引:1
Noble R.A. Jones A.D.R. Robertson T.J. Hutchins D.A. Billson D.R. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2001,48(6):1495-1507
Surface micromachined, capacitive ultrasonic transducers have been fabricated using a low thermal budget, CMOS-compatible process. This process allows inherent control of parameters such as membrane size and thickness, cavity size and the intrinsic stress in the membrane to be achieved. Devices fabricated using this process exhibit interesting properties for transduction in air at frequencies in excess of 1 MHz when driven from a standard ultrasonic voltage source. Experiments have been performed with devices containing silicon nitride membranes of variable thicknesses over a 2 μm thick air cavity and with device dimensions of up to 5 mm square. This is much larger than has been reported for a device with a single membrane. Calibration measurements using 1/8 inch microphones in air, and miniature PVDF hyrdophones in water, have been performed. The dependence on d.c. bias voltage is examined, involving static membrane deflection measurements and received peak voltages. Pulse-echo and pitch-catch mode operation have been achieved. Interferometric measurements of membrane displacement have been performed in air to illustrate the membrane deflection characteristics. Operation in liquids is also discussed 相似文献
997.
J. A. Murphy E. Gleeson G. Cahill W. Lanigan C. O’Sullivan E. Cartwright S. E. Church J. Hinderks E. Kirby K. Thompson B. Rusholme W. K. Gear B. Maffei P. A. R. Ade C. Tucker B. Jones 《Journal of Infrared, Millimeter and Terahertz Waves》2005,26(4):505-523
In this paper we report on the design and validation process for the profiled corrugated horn antennas, which feed the bolometer array of a cosmology experiment known as QUaD located at the South Pole. This is a cosmic background radiation polarization project, which demands precise knowledge and control of the optical coupling to the signal in order to map the feeble E- and B-polarization mode structure. The system will operate in two millimeter wavelength bands at 100 and 150 GHz. The imaging horn array collects the incoming signal via on-axis front-end optics and a Cassegrain telescope, with a cold stop in front of the array to terminate side-lobe structure at an edge taper of ?20dB. The corrugated horn design process was undertaken using in-house analytical software tools, based on modal scattering, specially developed for millimeter -wave profiled horn antennas. An important part of the instrument development was the validation of the horn design, in particular to verify low edge taper levels and the required well-defined band edges. Suitable feed horn designs were measured and were found to be in excellent agreement with theoretical predictions. 相似文献
998.
999.
Research on the Relationship Between Verbal and Nonverbal Communication: Emerging Integrations 总被引:1,自引:0,他引:1
The authors argue for an integrated approach in which verbal and nonverbal messages are studied as inseparable phenomena when they occur together. Addressed are assumptions of various forms of this type of research, potential relationships of quantitative and qualitative studies, current trends found in the investigations included in this special issue, and recommendations for further work. 相似文献
1000.
Tyler Guin Michelle Krecker Aaron Milhorn David A. Hagen Bart Stevens Jaime C. Grunlan 《Advanced Materials Interfaces》2015,2(11)
Layer‐by‐layer (LbL) assembly is a powerful and versatile technique to deposit functional thin films, but often requires a large number of deposition steps to achieve a film thick enough to provide a desired property. By incorporating amine salts into the cationic polyelectrolyte and its associated rinse, LbL clay‐containing nanocomposite films can achieve much greater thickness (>1 μm) with relatively few deposition cycles (≤6 bilayers). Amine salts interact with nanoclays, causing nanoplatelets to deposit in stacks rather than as individual platelets. This technique appears to be universal, exhibiting thick growth with multiple types of nanoclay, including montmorillonite and vermiculite (VMT), and a variety of amine salts (e.g., hexylamine and diethanolamine). The characteristic order found in LbL‐assembled films is maintained despite the incredible thickness. Films assembled in this manner achieve oxygen transmission rates below 0.009 cc m−2 d−1 atm−1 with just 6 bilayers (BLs) of chitosan/VMT deposited. These thick clay‐based thin films also impart exceptional flame resistance. A 2‐BL film renders a 3.2 mm polystyrene plate self‐extinguishing, while an 8‐BL film (3.9 μm thick) prevents ignition entirely. This ability to generate much thicker clay‐based multilayers with amine salts opens up tremendous potential for these nanocoatings in real world applications. 相似文献