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131.
132.
Bruna A Bregadiolli Hasina H Ramanitra Rodrigo Marques Ferreira Laura Corcoles Milton S Gomes Lauren Kang Craig MS Combe Hugo Santos Silva Francisco C Lavarda Didier Bégué Christine Dagron‐Lartigau Maria Luiza M Rocco Christine K Luscombe Clarissa A Olivati Carlos FO Graeff Roger C Hiorns 《Polymer International》2017,66(10):i-i
The cover image, by Bruna A. Bregadiolli et al., is based on the Research Article Towards the synthesis of poly(azafulleroid)s: main chain fullerene oligomers for organic photovoltaic devices, DOI: 10.1002/pi.5419 .
133.
Indium oxide (In2O3) nanorods were hydrothermally synthesized from aqueous InCl3 solution in urea with addition of polyvinylpyrrolidone (PVP) as a steric stabilizer. Indium hydroxide, In(OH)3, was precipitated at 60 °C and was changed into a transient InOOH phase upon calcination at 250 °C in air. X-ray diffractometry revealed that the existence of PVP delays the phase transformation of InOOH. Cubic-structured In2O3 phase was then formed when temperature was raised to 350 °C, regardless of the PVP concentration. The In(OH)3 phase without the PVP showed a rod-based, flower-like morphology of polycrystalline character. Minor addition of the PVP, i.e., 0.1–2 wt.%, resulted in a pronounced evolution in morphology from the three-dimensional, flower-like form to discrete, one-dimensional nanorods aligned in planar form. Both the flower-like and discrete nanorod morphologies were preserved after heat treatments at 250 and 350 °C. This reveals that the morphological change is attributable to preferential adsorption of the PVP molecules on the In(OH)3 crystallite surface, so that the aggregate attachment responsible for the multipod growth is inhibited. 相似文献
134.
A novel and versatile synthesis route has been developed to fabricate hollow Al2 O3 microspheres with nanoporous shell structures. The method involves a preferential "implantation" of Al species into polymeric template particles to form a core–shell structure in solvent. The template cores can then be removed by thermal pyrolysis to form hollow interiors. This unique "implantation" process allows for synthesis of monodisperse hollow spheres with a nonaggregated character. The implantation of Al species is confirmed by electron spectroscopy for chemical analysis/Auger analysis in depth profiles. The shell structure changes from amorphous to γ-Al2 O3 at 900°C; because of which, the shell is nanoporous in structure. The porous shell then transforms to α-Al2 O3 as temperature is further raised above 1000°C. Transmission electron microscopy examination reveals a uniform shell thickness of ca. 20–40 nm, and grain growth appears to be constrained by the thin shell walls at 1100°C, leading to void formation at the triple grain junctions. 相似文献
135.
Finite element modeling of segmental chip formation in high-speed orthogonal cutting 总被引:1,自引:0,他引:1
J. Hashemi A. A. Tseng P. C. Chou 《Journal of Materials Engineering and Performance》1994,3(6):712-721
An explicit, Lagrangian, elastic-plastic, finite element code has been modified to accommodate chip separation, segmentation,
and interaction in modeling of continuous and segmented chip formation in highspeed orthogonal metal cutting process. A fracture
algorithm has been implemented that simulates the separation of the chip from the workpiece and the simultaneous breakage
of the chip into multiple segments. The path of chip separation and breakage is not assigned in advance but rather is controlled
by the state of stress and strain induced by tool penetration. A special contact algorithm has been developed that automatically
updates newly created surfaces as a result of chip separation and breakage and flags them as contact surfaces. This allows
for simulation of contact between tool and newly created surfaces as well as contact between simulated chip segments. The
work material is modeled as elastic/perfectly plastic, and the entire cutting process from initial tool workpiece contact
to final separation of chip from workpiece is simulated. In this paper, the results of the numerical simulation of continuous
and segmented chip formation in orthogonal metal cutting of material are presented in the form of chip geometry, stress, and
strain contours in the critical regions. 相似文献
136.
Chi-Yuan Lu Hui-Hsin Tseng Ming-Yen Wey Ting-Wei Hsueh 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2009,145(3):461-467
Carbon nanotubes (CNTs) are relatively potential materials for catalyst supports. CNT-supported Cu catalysts were prepared by an impregnation method and a polyol process. The catalytic activity was examined under different reaction atmospheres, Cu contents, and sizes of supports for CO oxidation. The experimental results showed that the active phase on the catalyst prepared by the impregnation method (10–20 nm) was smaller than that on the catalyst prepared by the polyol process (30–50 nm). Furthermore, the smaller active phase showed better performance for CO oxidation. Therefore, catalysts prepared by the impregnation method had a lower activation energy (57.47 kJ mol?1) than those prepared by the polyol process. The optimum CNT-supported Cu catalyst prepared by the impregnation method using 10–20 nm CNTs had a Cu content of 13.4 wt.%, and a CO conversion of 33% achieved at 125 °C with a total space velocity of 1.56 × 105 h?1. 相似文献
137.
A dimethylsilylene‐bridged metallocene complex, (CH3)2Si(Ind)2ZrCl2, was supported on a nanosized silica particle, whose surface area was mostly external. The resulting catalyst was used to catalyze the polymerization of propylene to polypropylene. Under identical reaction conditions, a nanosized catalyst exhibited much better polymerization activity than a microsized catalyst. At the optimum polymerization temperature of 55°C, the former had 80% higher activity than the latter. In addition, the nanosized catalyst produced a polymer with a greater molecular weight, a narrower molecular weight distribution, and a higher melting point in comparison with the microsized catalyst. The nanosized catalyst's superiority was ascribed to the higher monomer concentration at its external active sites (which were free from internal diffusion resistance) and was also attributed to its much larger surface area. Electron microscopy results showed that the nanosized catalyst produced polymer particles of similar sizes and shapes, indicating that each nanosized catalyst particle had uniform polymerization activity. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
138.
139.
The main topics discussed in this paper include sensor integration, data extraction, data processing, monitoring the cutting tool, safety of the tool machinery, and quality of the components in processing. The detection method used in this paper is to extract the workload of a spindle motor from a CNC controller, and then transmit the data via a I/O card for further processing. The computer is connected to the CNC by DNC and is able to detect abnormal conditions and transmit, through DNC, to CNC the NC program to stop the machine or to replace the cutting tool. The systematic architectural instrument develops tools with object-oriented professional software and establishes software structure using a visual component library. The software component structure is made easy for maintaining and extending programs and for the operating system with its graphics user interface. 相似文献
140.
Pharaoh Fellow Mwale Chi-Hsin Lee Peng-Nien Huang Sung-Nien Tseng Shin-Ru Shih Hsin-Yuan Huang Sy-Jye Leu Yun-Ju Huang Liao-Chun Chiang Yan-Chiao Mao Wei-Chu Wang Yi-Yuan Yang 《International journal of molecular sciences》2021,22(8)
Coxsackievirus A16 (CA16) is one of the major causative agents of hand, foot, and mouth disease (HFMD). Children aged <5 years are the most affected by CA16 HFMD globally. Although clinical symptoms of CA16 infections are usually mild, severe complications, such as aseptic meningitis or even death, have been recorded. Currently, no vaccine or antiviral therapy for CA16 infection exists. Single-chain variable fragment (scFv) antibodies significantly inhibit viral infection and could be a potential treatment for controlling the infection. In this study, scFv phage display libraries were constructed from splenocytes of a laying hen immunized with CA16-infected lysate. The pComb3X vector containing the scFv genes was introduced into ER2738 Escherichia coli and rescued by helper phages to express scFv molecules. After screening with five cycles of bio-panning, an effective scFv antibody showing favorable binding activity to proteins in CA16-infected lysate on ELISA plates was selected. Importantly, the selected scFv clone showed a neutralizing capability against the CA16 virus and cross-reacted with viral proteins in EV71-infected lysate. Intriguingly, polyclonal IgY antibody not only showed binding specificity against proteins in CA16-infected lysate but also showed significant neutralization activities. Nevertheless, IgY-binding protein did not cross-react with proteins in EV71-infected lysate. These results suggest that the IgY- and scFv-binding protein antibodies provide protection against CA16 viral infection in in vitro assays and may be potential candidates for treating CA16 infection in vulnerable young children. 相似文献