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71.
Suzuki I Yamada K Yamakawa T Hashiba M Akazawa K 《Computer methods and programs in biomedicine》2003,70(3):253-258
We developed a low cost, user-friendly multimedia delivery system, to provide medical lectures saved as multimedia contents to persons engaged in medicine. This system was created using the RealSystem package with the TCP/IP network. Users can review lectures and medical meeting presentations with video and audio through the Internet, whenever convenient. Each medical source of video and slide has been clearly displayed on a screen. Members of medical associations or medical students can easily review the most interesting parts of these files. This system is being used efficiently in distance learning and aids the diffusion of the latest information and technology to busy physicians and medical students. 相似文献
72.
A variable-pressure scanning electron microscopy (VP-SEM) with a cooling stage permits long hours of observation of water-containing specimens in their natural or close to natural state, without the conventional specimen preparations of fixation, dehydration, drying and metal coating. It reduces water vaporization and beam damage by keeping the specimens at a low temperature. We observed Bacillus cereus colonies on nutrient agar, which would shrink significantly if any conventional specimen preparation technique were used. We also studied the growing process of the bacteria on raw and steamed rice using the VP-SEM without conventional preparation techniques. Original specimens were directly mounted onto specimen holders and their backscattered electron images observed under the following conditions: specimen stage temperature, -10 degrees C; specimen chamber vacuum level, 30-70 Pa; and accelerating voltage, 15-20 kV. We recognized that the VP-SEM minimized deformation of the colonies due to shrinkage of the nutrient agar, and successfully imaged the morphology of the colonies and bacteria without a decline in bacteria number, which is apt to occur during fixation and dehydration. Also, the growth process of the bacteria on raw or steamed rice could be observed promptly, since there is no specimen preparation step. 相似文献
73.
T. Kobayashi S. Morishita T. Honma K. Abe Y. Ukyo H. Iwahara 《Journal of Materials Science》2000,35(21):5283-5289
The stability of the SrZr0.9Yb0.1O3– protonic conductor in an atmosphere containing nitrogen oxides (NO
x
) was investigated. When a fine powder of SrZr0.9Yb0.1O3– with a specific surface area of about 50 m2/g was annealed at 440 °C in He gas containing 8% O2 and 0.1% NO, the formation of Sr(NO3)2 was observed by IR measurement, ion-chromatography analysis and ICP analysis. The formation mechanism of Sr(NO3)2 was examined by considering the thermodynamic equilibrium. Based on the results of the thermodynamic calculation, H2O dissolved into SrZr0.9Yb0.1O3– was estimated to play an important role in the reaction for the formation of Sr(NO3)2 between SrZr0.9Yb0.1O3– and NO
x
. 相似文献
74.
This paper considers a fault-tolerant decentralized H-infinity control problem for multi-channel linear time-invariant systems. The purpose is to design a decentralized H-infinity output feedback controller to.stabilize the given system and achieve a certain H-infinity performance requirement both in the normal situation and in the situation where any one of the local controllers fails. The designed problem is reduced to a feasibility problem of a set of bilinear matrix inequalities (BMIs). An algorithm is proposed to solve the BMIs. First, the normal situation is considered where all the local controllers are functioning. The local controllers are obtained from a standard centralized H-infinity controller by using a homotopy method imposing a structural constraint progressively. Secondly, the above case is extended to the one where any one of the local controllers fails. We again use a homotopy method where the coefficient matrices of the failed controller are decreased progressively to zero. The efficiency of the proposed algorithm is demonstrated by an example. 相似文献
75.
Morishita F. Hayashi I. Gyohten T. Noda H. Ipposhi T. Shimano H. Dosaka K. Arimoto K. 《Solid-State Circuits, IEEE Journal of》2007,42(4):853-861
A twin-transistor random access memory (TTRAM) can provide high speed, low power and high density with CMOS compatible SOI process. However it is difficult to handle as the unified memory required for advanced SoC because it needs the simple control sensing operation for memory compiler, higher cell efficiency, and lower voltage operation for dynamic frequency and voltage control. Enhanced TTRAM (ET2RAM) applies the actively body-bias control technique to realize the low voltage array operation, and never require the negative voltage source. The ET2RAM can realize both 263 MHz at 0.8 V and 10.2 mW at 0.5 V random-cycle operation, higher cell efficiency, and process scalability. It also provides the simple control method suitable for the unified macro for system-level power management SoC with keeping the merits of TTRAM as CMOS compatibility 相似文献
76.
Kyohei Terao Chihiro Masuda Ryo Inukai Murat Gel Hidehiro Oana Masao Washizu Takaaki Suzuki Hidekuni Takao Fusao Shimokawa Fumikazu Oohira 《IET nanobiotechnology / IET》2016,10(3):124
Optical tweezers are powerful tools for manipulating single DNA molecules using fluorescence microscopy, particularly in nanotechnology‐based DNA analysis. We previously proposed a manipulation technique using microstructures driven by optical tweezers that allows the handling of single giant DNA molecules of millimetre length that cannot be manipulated by conventional techniques. To further develop this technique, the authors characterised the microstructures quantitatively from the view point of fabrication and efficiency of DNA manipulation under a fluorescence microscope. The success rate and precision of the fabrications were evaluated. The results indicate that the microstructures are obtained in an aqueous solution with a precision ∼50 nm at concentrations in the order of 106 particles/ml. The visibility of these microstructures under a fluorescence microscope was also characterised, along with the elucidation of the fabrication parameters needed to fine tune visibility. Manipulating yeast chromosomal DNA molecules with the microstructures illustrated the relationship between the efficiency of manipulation and the geometrical shape of the microstructure. This report provides the guidelines for designing microstructures used in single DNA molecule analysis based on on‐site DNA manipulation, and is expected to broaden the applications of this technique in the future.Inspec keywords: DNA, molecular biophysics, fluorescence, optical microscopy, radiation pressure, biological techniquesOther keywords: optically driven microstructures, single DNA molecule analysis, fluorescence microscopy, optical tweezers, nanotechnology‐based DNA analysis, manipulation technique, aqueous solution, fine tune visibility, yeast chromosomal DNA molecules, geometrical shape, on‐site DNA manipulation 相似文献
77.
Ohmori T Morita H Tanaka M Miyauchi K Kasai D Furukawa K Miyashita K Ogawa N Masai E Fukuda M 《Journal of Bioscience and Bioengineering》2011,111(4):437-442
Rhodococcus jostii RHA1 accumulates chlorobenzoates (CBA) during the degradation of polychlorinated biphenyls (PCBs). CBA degradation is considered one of the rate-limiting steps in the complete degradation of PCBs. To reduce the accumulation of CBAs, the upper pathway enzyme genes for PCB degradation of RHA1 were introduced into a CBA-degrading bacterium, Burkholderia sp. NK8. The resulting recombinant strain exhibited no biphenyl 2,3-dioxygenase (BphA) activity encoded by bphAaAbAcAd genes, which encode the large and small subunits of the terminal oxygenase component and the ferredoxin and reductase subunits responsible for electron transfer from NADH to the large subunit. The remaining enzyme genes involved in the transformation of biphenyl to benzoate, bphB2C1D1, which encode dehydrogenase, ring-cleavage dioxygenase and hydrolase, conferred activities to NK8. To obtain the BphA activity of RHA1 in NK8, sets of BphA genes were constructed by combining the bphAaAbAcAd genes of RHA1 and bphA3A4 of Pseudomonas pseudoalcaligenes KF707, encoding the ferredoxin and reductase subunits. Hybrid derivatives of BphA containing the KF707 bphA3 conferred BphA activity to NK8, and a derivative containing the RHA1 bphAaAb and KF707 bphA3A4 genes exhibited the highest BphA activity. A plasmid containing the RHA1 bphAaAb and KF707 bphA3A4 genes plus the RHA1 bphB2C1D1 genes was constructed and introduced into NK8. The resulting recombinant strain efficiently degraded 2-, 3- and 4-chlorobiphenyls with an apparent reduction in CBA accumulation in comparison to the recombinant mutant strain, which had an insertion in the cbeA gene to inactivate CBA dioxygenase. 相似文献
78.
Zhen-Yan Deng Yoshiaki Inagaki Jihong She Yoshihisa Tanaka Yu-Fu Liu Masao Sakamoto Tatsuki Ohji 《Journal of the American Ceramic Society》2005,88(2):462-465
Long crack R -curve of a porous Si3 N4 with aligned fibrous grains was investigated, using a chevron-notched beam technique. A crack was constrained to propagate normal to the grain alignment. The crack growth resistance of aligned porous Si3 N4 was much larger compared with that of dense Si3 N4 ceramics. Microstructure observations showed that pullouts of fibrous grains in aligned porous Si3 N4 markedly increased during crack propagation relative to those of dense Si3 N4 , due to the existence of pores. The efficient grain pullouts in porous Si3 N4 increased the bridging stress at the crack wake. 相似文献
79.
Masao Sugawara Masamitsu Kataoka Kazunori Odashima Yoshio Umezawa 《Thin solid films》1989,180(1-2):129-133
Biomimetic “ion-channel sensors” based on host-guest molecular recognition were constructed by incorporating several kinds of receptor molecules in Langmuir-Blodgett (LB) molecular assemblies deposited directly on glassy carbon electrodes. The receptors used were valinomycin, bis(crown ether)s, macrocyclic polyamine and cyclodextrin polyamine. The binding of charged stimulants (metal ions, inorganic and organic anions) to these receptors induced a marked increase (or decrease) in the ion permeability of the membranes, as detected by cyclic voltammetry using [Fe(CN)6]4- or [Ru(bpy)3]2+ as marker ion. Such a mode of response, corresponding to model “channel opening (or closing)”, can be explained on the basis of the charge-charge interaction involving the stimulant, marker ion and lipid. 相似文献
80.
Tetsushi Oka Toyokazu Abe Kaoru Sugita Masao Yokota 《Artificial Life and Robotics》2009,13(2):455-459
This article describes a multimodal command language for home robot users, and a robot system which interprets users’ messages
in the language through microphones, visual and tactile sensors, and control buttons. The command language comprises a set
of grammar rules, a lexicon, and nonverbal events detected in hand gestures, readings of tactile sensors attached to the robots,
and buttons on the controllers in the users’ hands. Prototype humanoid systems which immediately execute commands in the language
are also presented, along with preliminary experiments of faceto-face interactions and teleoperations. Subjects unfamiliar
with the language were able to command humanoids and complete their tasks with brief documents at hand, given a short demonstration
beforehand. The command understanding system operating on PCs responded to multimodal commands without significant delay.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献