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991.
OR Spectrum - This paper deals with a special vehicle routing problem with backhauls where customers may want to receive items from a depot and, at the same time, return items back to the depot.... 相似文献
992.
993.
Milica Košević Srecko Stopic Andreas Bulan Jürgen Kintrup Reiner Weber Jasmina Stevanović Vladimir Panić Bernd Friedrich 《Advanced Powder Technology》2017,28(1):43-49
Synthesis and subsequent deposition of sub-micron spherical RuO2/TiO2 particles onto titanium were performed by continuous process in two connected reactors, exclusively applied for this purpose. Synthesis of particles was achieved by ultrasonic spray pyrolysis method in the first reactor. The deposition of thus produced RuO2/TiO2 onto an expanded titanium substrate was performed at 500 °C afterwards in the second, specially constructed, reactor equipped by high-voltage electrostatic field. Basic electrochemical properties of the obtained RuO2/TiO2 particles were checked in a form of the coating on Ti deposited from the suspension of the material produced in the first reactor. Thus prepared anode was investigated by cyclic voltammetry (CV), polarization measurements in O2 (OER) and Cl2 (CER) evolution and the accelerated stability test in diluted chloride solution. The morphology and composition of the deposited RuO2/TiO2 were checked by scanning electron microscopy/energy dispersive X-ray spectroscopy analysis. Analysis of the results obtained for OER and CER showed that Tafel slopes for these reactions were in accordance with the values for this kind of material. The CV response was of usual characteristics too. The accelerated stability test revealed acceptable anode stability. 相似文献
994.
995.
Sascha Kulas Christian Vogt Andreas Resch Jonas Hartwig Sven Ganske Jonas Matthias Dennis Schlippert Thijs Wendrich Wolfgang Ertmer Ernst Maria Rasel Marcin Damjanic Peter Weßels Anja Kohfeldt Erdenetsetseg Luvsandamdin Max Schiemangk Christoph Grzeschik Markus Krutzik Andreas Wicht Achim Peters Sven Herrmann Claus Lämmerzahl 《Microgravity science and technology》2017,29(1-2):37-48
996.
Evelyn Ploetz Andreas Zimpel Valentina Cauda David Bauer Don C. Lamb Christoph Haisch Stefan Zahler Angelika M. Vollmar Stefan Wuttke Hanna Engelke 《Advanced materials (Deerfield Beach, Fla.)》2020,32(19):1907267
Ion homeostasis is essential for cellular survival, and elevated concentrations of specific ions are used to start distinct forms of programmed cell death. However, investigating the influence of certain ions on cells in a controlled way has been hampered due to the tight regulation of ion import by cells. Here, it is shown that lipid-coated iron-based metal–organic framework nanoparticles are able to deliver and release high amounts of iron ions into cells. While high concentrations of iron often trigger ferroptosis, here, the released iron induces pyroptosis, a form of cell death involving the immune system. The iron release occurs only in slightly acidic extracellular environments restricting cell death to cells in acidic microenvironments and allowing for external control. The release mechanism is based on endocytosis facilitated by the lipid-coating followed by degradation of the nanoparticle in the lysosome via cysteine-mediated reduction, which is enhanced in slightly acidic extracellular environment. Thus, a new functionality of hybrid nanoparticles is demonstrated, which uses their nanoarchitecture to facilitate controlled ion delivery into cells. Based on the selectivity for acidic microenvironments, the described nanoparticles may also be used for immunotherapy: the nanoparticles may directly affect the primary tumor and the induced pyroptosis activates the immune system. 相似文献
997.
Vaishnavi Krishnamurthi Hareem Khan Taimur Ahmed Ali Zavabeti Sherif Abdulkader Tawfik Shubhendra Kumar Jain Michelle J. S. Spencer Sivacarendran Balendhran Kenneth B Crozier Ziyuan Li Lan Fu Md Mohiuddin Mei Xian Low Babar Shabbir Andreas Boes Arnan Mitchell Christopher F. McConville Yongxiang Li Kourosh Kalantar-Zadeh Nasir Mahmood Sumeet Walia 《Advanced materials (Deerfield Beach, Fla.)》2020,32(45):2004247
Atomically thin materials face an ongoing challenge of scalability, hampering practical deployment despite their fascinating properties. Tin monosulfide (SnS), a low-cost, naturally abundant layered material with a tunable bandgap, displays properties of superior carrier mobility and large absorption coefficient at atomic thicknesses, making it attractive for electronics and optoelectronics. However, the lack of successful synthesis techniques to prepare large-area and stoichiometric atomically thin SnS layers (mainly due to the strong interlayer interactions) has prevented exploration of these properties for versatile applications. Here, SnS layers are printed with thicknesses varying from a single unit cell (0.8 nm) to multiple stacked unit cells (≈1.8 nm) synthesized from metallic liquid tin, with lateral dimensions on the millimeter scale. It is reveal that these large-area SnS layers exhibit a broadband spectral response ranging from deep-ultraviolet (UV) to near-infrared (NIR) wavelengths (i.e., 280–850 nm) with fast photodetection capabilities. For single-unit-cell-thick layered SnS, the photodetectors show upto three orders of magnitude higher responsivity (927 A W−1) than commercial photodetectors at a room-temperature operating wavelength of 660 nm. This study opens a new pathway to synthesize reproduceable nanosheets of large lateral sizes for broadband, high-performance photodetectors. It also provides important technological implications for scalable applications in integrated optoelectronic circuits, sensing, and biomedical imaging. 相似文献
998.
Ann‐Katrin U. Michel Andreas Heßler Sebastian Meyer Julian Pries Yuan Yu Thomas Kalix Martin Lewin Julian Hanss Angela De Rose Tobias W. W. Maß Matthias Wuttig Dmitry N. Chigrin Thomas Taubner 《Advanced materials (Deerfield Beach, Fla.)》2019,31(29)
Nanometer‐thick active metasurfaces (MSs) based on phase‐change materials (PCMs) enable compact photonic components, offering adjustable functionalities for the manipulation of light, such as polarization filtering, lensing, and beam steering. Commonly, they feature multiple operation states by switching the whole PCM fully between two states of drastically different optical properties. Intermediate states of the PCM are also exploited to obtain gradual resonance shifts, which are usually uniform over the whole MS and described by effective medium response. For programmable MSs, however, the ability to selectively address and switch the PCM in individual meta‐atoms is required. Here, simultaneous control of size, position, and crystallization depth of the switched phase‐change material (PCM) volume within each meta‐atom in a proof‐of‐principle MS consisting of a PCM‐covered Al–nanorod antenna array is demonstrated. By modifying optical properties locally, amplitude and light phase can be programmed at the meta‐atom scale. As this goes beyond previous effective medium concepts, it will enable small adaptive corrections to external aberrations and fabrication errors or multiple complex functionalities programmable on the same MS. 相似文献
999.
Maximilian Hrner Katrin Raute Barbara Hummel Josef Madl Guido Creusen Oliver S. Thomas Erik H. Christen Natascha Hotz Raphael J. Gübeli Raphael Engesser Balder Rebmann Jasmin Lauer Bernd Rolauffs Jens Timmer Wolfgang W. A. Schamel Jan Pruszak Winfried Rmer Matias D. Zurbriggen Christian Friedrich Andreas Walther Susana Minguet Ritwick Sawarkar Wilfried Weber 《Advanced materials (Deerfield Beach, Fla.)》2019,31(12)
1000.
Andreas Stoll Kai Sun Kalaga Madhav Julia Fiebrandt Martin M. Roth 《Journal of Modern Optics》2019,66(8):829-834
The concept of an integrated spectrometer using coaxially joined fibre-segments is presented. The obtained spectrum is intrinsically cross-dispersed with respect to the free spectral ranges in both lateral directions. The key element is a multi-core fibre in which the N?×?N cores are arranged in a compact helical bundle spiralling around the fibre central axis. Dispersive properties of the core bundle and the mechanism for diffractive image formation are investigated. The spectral resolution and optical loss in relation to the fibre footprint is analysed. To resolve 25 channels with 1.6?nm spacing in the C-band, the device can be contained in a volume of 1-mm-diameter cladding over a length of ~10?cm. Furthermore, it is shown that an inverse taper structure can reduce the device loss dramatically by improving the wave-front overlap without exciting high-order modes, a feature that is not achievable in conventional planar spectrometers. 相似文献