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41.
Kang-Min KimAuthor VitaeHae-Ryong KimAuthor Vitae Kwon-Il ChoiAuthor VitaeHyo-Joong KimAuthor Vitae Jong-Heun LeeAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(2):745-751
Highly crystalline ZnO hierarchical nanostructures were prepared at room temperature through the alkaline hydrolysis of zinc salt by the forced mixing of two immiscible solutions: Zn-nitrate aqueous solution and oleic-acid-dissolved n-hexane solution. The oleic acid acted as a surfactant in the room-temperature formation of well-defined ZnO hierarchical nanostructures, which subsequently demonstrated a sensitive and selective detection of C2H5OH. The responses of these hierarchical nanostructures to 10-100 ppm C2H5OH ranged from 15.7 to 177.7, which were 7-9 times higher than those of the agglomerated nanoparticles. 相似文献
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邢蓉 《长春理工大学学报(自然科学版)》2006,29(4):113-116
利用铁粉和水之间水热反应合成Fe3O4纳米晶。XRD、FTIR、TEM和TG-DSC等分析测试结果表明:采用该法,在无任何表面活性剂或模板存在的情况下,在150℃,24h合成了平均厚度为82nm的片状Fe3O4纳米结构;在180℃,10h合成了平均厚度为96 nm的片状Fe3O4纳米结构;在180℃,24h合成了直径大小为35~47 nm和长度为190~714 nm的枝晶状Fe3O4纳米晶。最后,探讨了Fe3O4纳米晶的水热合成机理。 相似文献
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An experimental system based on a transmission electron microscope JEM-100CX has been developed for electron beam-induced chemical vapor deposition. Direct electron beam-induced growth of nanometer-wide self-supporting rods has been performed inside the microscope operating in scanning mode by decomposition of carbonyls of chromium Cr(CO)6, tungsten W(CO)6, and rhenium Re2(CO)10. In situ phase and structure transformations under annealing inside the microscope column were studied. Nanoscale rods and strips grown from rhenium carbonyl are of special interest because, after annealing, they consist of a single pure rhenium phase. The described method of metallic nanoelements fabrication enables us to produce highly conductive nanowires and tips for application in nanoelectronics, emission electronics, and scanning tunneling microscopy. 相似文献
45.
Cathodoluminescence study of semiconductor oxide micro- and nanostructures grown by vapor deposition
Nano- and microstructures of SnO(2), In(2)O(3) and ZnO have been grown during thermal treatment of compacted powders under argon flow. Indium-doped SnO(2) tube-shaped structures with rectangular cross-section are obtained by adding a fraction of In(2)O(3) to the starting SnO(2) powder. In-rich nanoislands were found to grow on some edges of the tubes. ZnO nanostructures doped with Sn or Eu were grown by adding SnO(2) and Eu(2)O(3) powder, respectively, to the ZnO precursor powder. All the samples have been characterized by the emissive and cathodoluminescence (CL) modes of scanning electron microscopy. CL images from SnO(2):In and In(2)O(3):Sn tubes and islands show a higher emission from the Sn-rich structures related to oxygen deficiency. CL of doped ZnO enables to detect the presence of dopant in specific regions or structures. CL appears to be a useful technique to study optical and electronic properties of semiconductor oxide nanostructures. 相似文献
46.
Organic light-emitting diodes (OLEDs) based on thermally activated delayed fluorescence (TADF) have emerged as promising alternatives to phosphorescent OLEDs for harvesting both singlet and triplet excitons. However, the development of TADF-OLEDs meets a thorny problem of serious efficiency roll-off at high luminance. Here, we demonstrate an approach to suppress the efficiency roll-off characteristics in TADF-OLEDs by localized surface plasmon resonance (LSPR) effect of easy-fabricated Ag-island nanostructures. Compared with the common TADF-OLEDs at a high current density of 100 mA cm−2, the efficiency roll-off ratio of the TADF-OLEDs with Ag-island nanostructures decreases from 49.75% to 35.76% significantly, and the maximum current efficiency is increased by 10.5%. The performance enhancement is mainly attributed to the coupling between excitons and localized surface plasmons (LSPs), which could alter the excited state kinetic characteristics of TADF molecules. 相似文献
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Siew Hui Voon Lik Voon Kiew Hong Boon Lee Siang Hui Lim Mohamed Ibrahim Noordin Anyanee Kamkaew Kevin Burgess Lip Yong Chung 《Small (Weinheim an der Bergstrasse, Germany)》2014,10(24):4993-5013
Animal models, particularly rodents, are major translational models for evaluating novel anticancer therapeutics. In this review, different types of nanostructure‐based photosensitizers that have advanced into the in vivo evaluation stage for the photodynamic therapy (PDT) of cancer are described. This article focuses on the in vivo efficacies of the nanostructures as delivery agents and as energy transducers for photosensitizers in animal models. These materials are useful in overcoming solubility issues, lack of tumor specificity, and access to tumors deep in healthy tissue. At the end of this article, the opportunities made possible by these multiplexed nanostructure‐based systems are summarized, as well as the considerable challenges associated with obtaining regulatory approval for such materials. The following questions are also addressed: (1) Is there a pressing demand for more nanoparticle materials? (2) What is the prognosis for regulatory approval of nanoparticles to be used in the clinic? 相似文献
50.
Ultrafast optical properties of U-shaped annular aperture arrays (UAAAs) fabricated on a silicon substrate were investigated for varying photodoping levels of the silicon from the back to front interfaces of the sample. Experimental data demonstrate that the transmission modulation depth of the multimode resonance can be realized about 90% under optical power 60 mW, and the off switch of these resonance peaks transmission can be also simultaneously achieved within several picoseconds. Such plasmonic structure is able to be used for ultrafast optical modulators, active terahertz plasmonics, and ultrafast optical off switch. 相似文献