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81.
The role of nanotopography on the long‐term response of progenitor cells is explored using polycaprolactone (PCL) nanopillar and nanofiber surfaces seeded with plastic‐adherent rat multipotent mesenchymal stromal cells (MSCs). After 4 weeks in culture under normal expansion media conditions, MSCs cultured on nanofibers exhibit better adherence, increased proliferation, and maintain increasingly dense fibroblast‐like morphologies. In contrast, MSCs seeded on nanopillar surfaces display lowered adherence, reduced proliferation, and adopt highly elongated cellular morphologies. Immunofluorescent staining of MSCs on PCL nanopillars reveals the presence of two bone marker proteins, osteopontin and osteocalcin, providing evidence for surface induced differentiation into osteoblast‐like cells. Unlike the nanopillar topography, MSCs cultured on nanofiber and smooth PCL surfaces did not appear to undergo osteogenesis. Observed differences in cellular response to the PCL nanotopographies offer strategies to direct progenitor cell populations solely based upon submicron surface modifications. This study provides a foundation for future work exploring variations in PCL nanopillar topography with the goal of optimizing adherence and osteogenic response of MSCs. 相似文献
82.
Amodini Mishra S. N. Choudhary R. N. P. Choudhary V. R. K. Murthy Kamal Prasad 《Journal of Materials Science: Materials in Electronics》2012,23(1):185-192
A new lead-free perovskite Ba(Bi1/2Ta1/2)O3 was prepared by conventional ceramic fabrication technique at 1,200 °C/4 h in air atmosphere. The crystal symmetry, space
group and unit cell dimensions were determined from the experimental results using FullProf software. The crystallite size
and lattice strain were estimated from Williamson-Hall approach. XRD analysis of the compound indicated the formation of a
single-phase cubic structure with the space group Pm3m. EDAX and SEM studies were carried out in order to evaluate the quality and purity of the compound. Permittivity data showed
a low temperature coefficient of capacitance (T
CC
< 4%) up to +125 °C. Complex impedance analyses suggested the dielectric relaxation to be of non-Debye type. Electric modulus
studies supported the hopping type of conduction in Ba(Bi1/2Ta1/2)O3. 相似文献
83.
A new process of flat absorber black nickel alloy coating was developed on stainless steel by electrodeposition from a bath containing nickel,zinc and ammonium sulphates;thiocyanate and sodium hypophosphite for space applications.Coating process was optimized by investigating the effects of plating parameters,viz concentration of bath constituents,current density,temperature,pH and plating time on the optical properties of the black deposits.Energy dispersive X-ray spectroscopy showed the inclusion of about 6% phosphorous in the coating.The scanning electron microscopy studies revealed the amorphous nature of the coating.The corrosion resistance of the coatings was evaluated by the electrochemical impedance spectroscopy (EIS) and linear polarization (LP) techniques.The results revealed that,phosphorous addition confers better corrosion resistance in comparison to conventional black nickel coatings.The black nickel coating obtained from hypophosphite bath provides high solar absorptance (α s) and infrared emittance (ε IR) of the order of 0.93.Environmental stability to space applications was established by the humidity and thermal cycling tests. 相似文献
84.
The relations for the growth and consumption rates of a layer with finite thickness as an end member and the product phases
in the interdiffusion zone are developed. We have used two different methodologies, the diffusion based and the physico-chemical
approach to develop the same relations. We have shown that the diffusion based approach is rather straightforward; however,
the physico-chemical approach is much more versatile than the other method. It was found that the position of the marker plane
becomes vague in the second stage of the interdiffusion process in pure A thin layer/B couple, where two phases grow simultaneously. 相似文献
85.
eWALL framework, under development in the European eWALL project (project no. 610658: “eWALL for Active Long Living”) is meant for care of population with age related impairments, mild dementia and COPD. Expanded eWALL (e2WALL) is planned to be an integrated quality framework for long-term care services which will cover very different types of care: all healthcare (both preventive and rehabilitative), societal services, care for cognitive diseases, services delivered at home as well as support for caregivers as an integral part of the quality improvement process. Thus, we present e2WALL home system that would encompass installation (setup) of e2WALL in homes (flats, houses and aging homes) and their management and maintenance across Europe, starting from the partners involved in eWALL (Austria, Bulgaria, Croatia, Denmark, Former Yugoslav Republic of Macedonia, Germany, Greece, Italy, Montenegro, The Netherlands and Romania) and expanding the partnership to the most of Europe (e.g. United Kingdom, Poland, Czech Republic…). This would be a direct application of the developed e2WALL platform and should be done through a network of collaborating small-to-medium sized enterprises (SMEs), each of whom would lead the process of setting up e2WALL system and continuing to provide support services to homes in their respective country. In this way, the growth of high tech and innovative SMEs will be ensured at pan European level, which will enable growth over restricted national market and stimulate European investments in SMEs and startups. Actually, the bigger platform will enable e2WALL European Ecosystem (e4WALL), which can then expand into other non-European markets (e.g. Asia, USA) and means sustainability beyond the life of the project. e2WALL will lead to connected tech start-up hubs to the larger European business ecosystem and will contribute to increased access of country-specific and customized new product to the pan European market, which will lead to increase of employed qualified individuals. Another important focus would be creating an energy efficient environment for a new social network where registered users would provide on-demand services. 相似文献
86.
Debi Prasad Das Danielle J. Moreau Ben S. Cazzolato 《Control Engineering Practice》2013,21(4):544-555
In this paper, a feed-forward nonlinear active noise control algorithm is developed using the Filtered-S LMS (FSLMS) algorithm and virtual microphone control for an active headrest application. Virtual microphone control is implemented to attenuate noise at the ears of the headrest occupant using the physical microphones placed at remote locations. The proposed nonlinear virtual microphone control algorithm is verified in real-time in a headrest. Different nonlinear noise processes are studied and it is shown that in all cases, the FSLMS algorithm outperforms the FXLMS algorithm in controlling nonlinear primary noise at a virtual location. 相似文献
87.
Siba Prasad Sen 《大坝与安全》2017,(3)
印度兰吉特河(Rangit)是提斯塔河(Teesta)的主要支流,位于东喜马拉雅地区。兰吉特水电站装机60 MW,于2000年2月投入运行。每年5~9月汛期之间,兰吉特河输沙量巨大,2006年,该电站发生水淹厂房事故。 相似文献
88.
Sunil Kedia Subrata Pradhan Biswanath Rath Kalpesh Doshi Yohan Khristi Dipak Patel Upendra Prasad Ashoo N. Sharma 《Journal of Superconductivity and Novel Magnetism》2013,26(4):1289-1296
Stable operation of superconducting magnets depend critically on the balance of heat deposition rate versus heat extraction rate by the cryo-coolant. Thus, the mass flow rate of the coolant in case of force-flow cooled superconducting magnet with Cable-In-Co-nduit-Conductor (CICC) construction becomes an important factor for optimum stability of magnets. The Toroidal and Poloidal Field magnets of Steady-state Superconducting Tokamak-1 (SST-1) is made of superconducting CICC with a void fraction of 40 %±2 %. For adequate cooling of magnets, supercritical helium at 4 bar and 4.5 K is forced-flown through the voids. Effect of temperature on mass flow rate and pressure drop in SST-1 CICC is studied in a 7 m long piece wound helically. The experimental friction factor of the CICC is also measured at different temperatures and flow rates and is compared with the standard Katheder equation and Tada equation. Also, based on the new findings obtained from the experimental results, the dimensionless Reynolds number has been slightly modified. This new number is used to propose a modified Katheder correlation for the friction factor in CICCs similar to that of SST-1. 相似文献
89.
Sumit K. Mishra Nabanita Saha S. Singh Chhemendra Sharma M. V. S. N. Prasad Sachin Gautam Amit Misra Abhishek Gaur Deepika Bhattu Subhasish Ghosh Anubhav Dwivedi Rosalin Dalai Debajyoti Paul Tarun Gupta Sachchida N. Tripathi R. K. Kotnala 《Mapan》2017,32(3):229-241
Estimation of the direct radiative forcing (DRF) by atmospheric particles is uncertain to a large extent owing to uncertainties in their morphology (shape and size), mixing states, and chemical composition. A region-specific database of the aforementioned physico-chemical properties (at individual particle level) is necessary to improve numerically-estimated optical and radiative properties. Till date, there is no detailed observation of the above mentioned properties over Kanpur in the Indo-Gangetic Plain (IGP). To fill this gap, an experiment was carried out at Kanpur (IITK; 26.52°N, 80.23°E, 142 m msl), India from April to July, 2011. Particle types broadly classified as (a) Cu-rich particles mixed with carbon and sulphur (b) dust and clays mixed with carbonaceous species (c) Fe-rich particles mixed with carbon and sulfur and (d) calcite (CaCO3) particles aged with nitrate, were observed. The frequency distributions of aspect ratio (AR; indicator of extent of particle non-sphericity) of total 708 particles from April to June reveal that particles with aspect ratio range >1.2 to ≤1.4 were abundant throughout the experiment except during June when it was found to shift to high AR range, >1.4 to ≤1.6 (followed with another peak of AR i.e. >2 to ≤2.4) due to dust storm conditions enhancing the occurrence of more non-spherical particles over the sampling site. The spherical particles (and close to spherical shape; AR range, 1.0 to ≤1.2) were found to be <20% throughout the experiment with a minimum (11.5%) during June. Consideration of Homogeneous Equivalent Sphere Approximation (HESA) in the optical/radiative model over the study region is found to be irrelevant during the campaign. 相似文献
90.