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991.
Comparative study of microwave and conventional methods for the preparation and optical properties of novel MgO-micro and nano-structures 总被引:1,自引:0,他引:1
N. Clament Sagaya SelvamR. Thinesh Kumar L. John KennedyJ. Judith Vijaya 《Journal of Alloys and Compounds》2011,509(41):9809-9815
Magnesium oxide (MgO) was synthesised by a simple microwave-assisted combustion route without using any template, catalyst or surfactant. For the purpose of comparison, it was also prepared using conventional method. The as-synthesized MgO was characterized by powder X-ray diffraction (XRD), Fourier Transform infrared spectra (FT-IR), high resolution scanning electron microscopy (HR-SEM), transmission electron microscopy (TEM), Energy Dispersive X-ray analysis (EDX), diffuse reflectance spectroscopy (DRS) and Photoluminescence (PL) spectroscopy. The XRD results confirmed the formation of cubic phase MgO. FT-IR was used to investigate the adsorption of water and CO2 on MgO surface and confirm the formation of Mg-O phase. The formation of MgO micro cubes structures was confirmed by HR-SEM. The formation of MgO nanosheets was confirmed by HR-SEM and TEM and their possible formation mechanisms were also proposed. The optical absorption and photoluminescence emissions were determined by DRS and PL spectra respectively. An attempt has been made to compare the lattice parameter and the PL intensity. 相似文献
992.
A three-dimensional heat transfer model is developed to simulate the cladding process that include the different physical phenomena such as heat transfer, phase changes, addition of powder particles and fluid flow due to Marangoni–Rayleigh–Benard convection. It is found that the Rayleigh–Benard convection is insignificant and Marangoni–Benard convection is dominant for the studied cases. By varying the scanning speed and Marangoni number the melt pool size and strength of convection are changed and its influence on clad built-up geometry, dilution level, maximum and average melt pool temperatures and the form and scale of the microstructure of the solidified clad track has been studied. 相似文献
993.
994.
L. Satyanarayan Anish Kumar T. Jayakumar C. V. Krishnamurthy Krishnan Balasubramaniam Baldev Raj 《Journal of Nondestructive Evaluation》2009,28(3-4):111-124
New techniques developed using the array transducer, to image and size the bottom-surface and near-through-wall crack-like defects in thick carbon steel components are discussed. Three studies are reported here including (a) Optimal beam steering angle for focused and unfocused inspection using phased array method for bottom-surface crack sizing. (b) A front wall correction algorithm for sizing of near-through-wall crack-like defects. (c) A small aperture technique for sizing of near-through-wall crack-like defects. A Finite Difference Time Domain (FDTD) based simulation was used to study and verify the experimental observations. The application of time domain scheme relative arrival time technique (RATT), to measure the size of the near-through wall crack-like defects for the leak before break (LBB) criterion, was also investigated and found to be insufficient. A conventional SAFT algorithm was used for improving the sizing using the small aperture technique. 相似文献
995.
A comparative study based on the thermal performance of elliptical and offset-halves journal bearings has been carried out by solving energy equation while assuming Parabolic Temperature Profile Approximation across the fluid film for faster computation of temperatures. Investigation for the rise in oil film temperatures, thermal pressures, load capacity, and power loss for three commercially available grade oils have been carried out for bearing configurations under study. It has been found that the offset-halves journal bearing runs cooler when compared with elliptical journal bearing profile with minimum power loss and good load capacity using Oil 2 as lubricant for which minimum thermal degradation has been observed. 相似文献
996.
Abstract Radio Frequency Identification (RFID) technology can be applied to a number of pharmaceutical processes, as ample of information can be stored and read rapidly from an RFID tag. Applications may range from inventory control, to access control, to telemedicine, to supply chain management and, most importantly, in combatting counterfeit products. Overall health care services can be improved by using this technology. This technology is gaining popularity in various fields, but is still costly and regulatory considerations are restricting its use. This paper explains the basics of RFID technology and some potential applications related to the pharmaceutical industry. 相似文献
997.
Swadesh Kumar Singh 《International Journal of Material Forming》2010,3(4):259-266
Anisotropy and strain rate sensitivity index (m) plays a very important role in the formability of materials. In the present investigation strain ratios in 0°, 45° and 90° to the rolling direction and the strain rate sensitivity index were calculated at different temperatures. After developing the data from experiments, Artificial Neural Network (ANN) models are trained for different properties. Trained ANN models are used to calculate different strain ratios and sensitivity index at unknown temperatures. The results are promising and the percentage error in ANN prediction is found to be around 10%. 相似文献
998.
Salleh Emee Marina Zuhailawati Hussain Ramakrishnan Sivakumar Dhindaw Brij Kumar 《Metallurgical and Materials Transactions A》2017,48(5):2519-2528
Metallurgical and Materials Transactions A - Magnesium (Mg) and its alloys have shown potential for use in the biomedical industry due to their excellent biological performance and biodegradability... 相似文献
999.
Jung-Hoon Kim Shishir Kumar Behera Seok-Young Oh Hung-Suck Park 《Water and Environment Journal》2010,24(4):293-302
Effluent qualities of five municipal wastewater treatment facilities (MWWTFs) in Ulsan were evaluated to examine their reuse potential. Effluent from Yongyeon (Y) MWWTF, Onsan (O) MWWTF and Bangeojin (B) MWWTFs can be used as cooling water without further treatment. As evident from Langelier saturation index and Ryzner index values, reuse of treated effluent from OMWWTF and BMWWTFs is recommended by controlling the pH to reduce the scale-forming potential of effluent. However, effluents from these MWWTFs need additional treatment to remove residual dissolved constituents before reuse as boiler water. Besides, effluent from Hoiya (H) MWWTF and Unyang (U) MWWTFs can be reused for agricultural irrigation without any additional treatment. Based on the scientific results obtained from this investigation, proper application of technology and promotion of public awareness to change the traditional mindset for treated effluent reuse could immensely contribute towards conserving local water resources and addressing global environmental problems on a regional basis. 相似文献
1000.
Ajay Kumar Shukla Ryabov Dmitry Olena Volkova Piotr R. Scheller Brahma Deo 《Metallurgical and Materials Transactions B》2011,42(1):224-235
The melting of steel scrap in high temperature liquid iron melt is investigated by conducting cold model experiments of the
melting of ice sample of different geometries and sizes in an argon-stirred vessel containing water. The melting process of
ice samples is observed using a high-speed camera. Design of experiments is based on similarity criteria. The relationships
between non-dimensional groups related to heat transfer (Nu, Re, Pr, and Gr) are derived for different experimental conditions.
The results are compared with those reported in the literature. The heat transfer coefficient is estimated as a function of
mixing power and is found to be in good agreement with the calculated values obtained by using reported relationships in literature. 相似文献