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991.
Nozomu Matsunaga Shunsuke Imai Yuta Inokuchi Masamitsu Shimazawa Shigeru Yokota Yoko Araki Hideaki Hara 《Molecular nutrition & food research》2009,53(7):869-877
Our aim was to determine whether a Vaccinium myrtillus (bilberry) anthocyanoside (VMA) and/or its main anthocyanidin constituents (cyanidin, delphinidin, and malvidin) can protect retinal ganglion cells (RGCs) against retinal damage in vitro and in vivo. In RGC cultures (RGC‐5, a rat ganglion cell‐line transformed using E1A virus) in vitro, cell damage and radical activation were induced by 3‐(4‐morpholinyl) sydnonimine hydrochloride (SIN‐1, a peroxynitrite donor). Cell viability was measured using a water‐soluble tetrazolium salt assay. Intracellular radical activation within RGC‐5 cells was evaluated using 5‐(and‐6)‐chloromethyl‐2,7‐dichlorodihydrofluorescein diacetate acetyl ester (CM‐H2DCFDA). Lipid peroxidation was assessed using the supernatant fraction of mouse forebrain homogenates. In mice in vivo, we evaluated the effects of VMA on N‐methyl‐D ‐aspartic acid (NMDA)‐induced retinal damage using hematoxylin‐eosin and terminal deoxynucleotidyl transferase‐mediated dUTP nick‐end labeling (TUNEL) stainings. VMA and all three anthocyanidins (i) significantly inhibited SIN‐1‐induced neurotoxicity and radical activation in RGC‐5, (ii) concentration‐dependently inhibited lipid peroxidation in mouse forebrain homogenates. Intravitreously injected VMA significantly inhibited the NMDA‐induced morphological retinal damage and increase in TUNEL‐positive cells in the ganglion cell layer. Thus, VMA and its anthocyanidins have neuroprotective effects (exerted at least in part via an anti‐oxidation mechanism) in these in vitro and in vivo models of retinal diseases. 相似文献
992.
Yusuke Imai Naoki Kodama Susumu Takahashi Akinori Kan Yuji Hotta Hirotaka Ogawa 《应用聚合物科学杂志》2019,136(14):47315
The high-frequency dielectric, thermal, and mechanical properties of poly(2,6-dimethyl-1,4-phenylene ether)/high-impact polystyrene (PPE/HIPS) alloys compounded with MgO filler were investigated as a function of MgO content. A comparison with isotactic polypropylene/MgO composites was also carried out. Composite samples without voids were successfully prepared by melt-kneading and hot-pressing processes. A reduction of dielectric loss (tan δ) to less than 10−3 was achieved by adding 40 vol % of MgO to the PPE/HIPS alloys. The compositional dependencies of the real part of the dielectric constant (ε′), tan δ, and temperature coefficient of ε′ (TCε) showed correspondence with the Bruggeman theory. The decrease in thermal expansion with increasing filler concentration followed the logarithmic rule of mixture. The flexural moduli of the composites increased with MgO loading in accordance with the Nielsen theory. On the other hand, deteriorations were observed in flexural and Charpy impact strengths. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47315. 相似文献
993.
The rapidly developing interest in nanofluidic analysis, which is used to examine liquids ranging in amounts from the attoliter to the femtoliter scale, correlates with the recent interest in decreased sample amounts, such as in the field of single-cell analysis. For general nanofluidic analysis, the fact that a pressure-driven flow does not limit the choice of solvents (aqueous or organic) is important. This study shows the first pressure-driven liquid chromatography technique that enables separation of atto- to femtoliter sample volumes, with a high separation efficiency within a few seconds. The apparent diffusion coefficient measurement of the unretentive sample suggests that there is no increase in the viscosity of toluene in the extended nanospace, unlike in aqueous solvents. Evaluation of the normal phase separation, therefore, should involve only the examination of the effect of the small size of the extended nanospace. Compared to a conventionally packed high-performance liquid chromatography column, the separation here results in a faster separation (4 s) by 2 orders of magnitude, a smaller injection volume (10(0) fL) by 9 orders, and a higher separation efficiency (440,000 plates/m) by 1 order. Moreover, the separation behavior agrees with the theory showing that this high efficiency was due to the small and controlled size of the separation channel, where the diffusion through the channel depth direction is fast enough to be neglected. Our chip-based platform should allow direct and real-time analysis or screening of ultralow volume of sample. 相似文献
994.
Imai T Yagi S Toyoda S Miyazu J Naganuma K Kawamura S Sasaura M Fujiura K 《Applied optics》2012,51(10):1532-1539
We fabricated cylindrical varifocal lenses with fast responses by using the strong Kerr effect of KTa(1-x)Nb(x)O(3) (KTN) single crystals. We observed focus shifts of up to 87 mm with the assistance of a 250 mm focal length lens, which corresponds to a focus shift from infinity to 720 mm by the KTN lens itself. The response time was as fast as 1 μs. We also present a simulation method for calculating refractive index distributions in KTN single crystals, which is essential when designing the lens. The method is characterized by the strain contribution, which has not conventionally been typical of electro-optic simulations. We used this method to explain the refractive index modulations that are characteristic of the varifocal lenses. 相似文献
995.
Yoshikawa M Negishi S Shima Y Hojo H Mase A Kogi Y Imai T 《The Review of scientific instruments》2010,81(10):10D514
Two dimensional (2D) plasma image analysis is useful to study the improvement of plasma confinement in magnetically confined fusion plasmas. We have constructed a 2D interferometer system with phase imaging method for studying 2D plasma density distribution and its fluctuation measurement in the tandem mirror GAMMA 10. 2D profiles of electron density and its fluctuation have been successfully obtained by using this 2D phase imaging system. We show that 2D plasma density and fluctuation profiles clearly depends on the axial confining potential formation with application of plug electron cyclotron heating in GAMMA 10. 相似文献
996.
Kimura T Mimura H Handa S Yumoto H Yokoyama H Imai S Matsuyama S Sano Y Tamasaku K Komura Y Nishino Y Yabashi M Ishikawa T Yamauchi K 《The Review of scientific instruments》2010,81(12):123704
In situ wavefront compensation is a promising method to realize a focus size of only a few nanometers for x-ray beams. However, precise compensation requires evaluation of the wavefront with an accuracy much shorter than the wavelength. Here, we characterized a one-dimensionally focused beam with a width of 7 nm at 20 keV using a multilayer mirror. We demonstrate that the wavefront can be determined precisely from multiple intensity profiles measured around the beamwaist. We compare the phase profiles recovered from intensity profiles measured under the same mirror condition but with three different aperture sizes and find that the accuracy of phase retrieval is as small as λ∕12. 相似文献
997.
998.
Tsuruta T 《Journal of Bioscience and Bioengineering》2004,97(4):275-277
The adsorption of uranium from an acidic solution by microbes was examined. High uranium adsorption ability was exhibited by actinomycetes. Streptomyces levoris cells could adsorb about 380 micromol of uranium per gram dry cells from the solution. The cells could adsorb uranium over a wide acidic pH range and very rapidly. The amount of uranium adsorbed from a solution containing uranium and thorium was affected by the thorium concentration. The amount adsorbed was reduced and an uranyl-thorium ion exchange reaction occurred in the case of adsorption from a solution containing both metals. 相似文献
999.
Takayuki Kanda Masayuki Kamasima Michita Imai Tetsuo Ono Daisuke Sakamoto Hiroshi Ishiguro Yuichiro Anzai 《Autonomous Robots》2007,22(1):87-100
This paper reports the findings for a humanoid robot that expresses its listening attitude and understanding to humans by
effectively using its body properties in a route guidance situation. A human teaches a route to the robot, and the developed
robot behaves similar to a human listener by utilizing both temporal and spatial cooperative behaviors to demonstrate that
it is indeed listening to its human counterpart. The robot's software consists of many communicative units and rules for selecting
appropriate communicative units. A communicative unit realizes a particular cooperative behavior such as eye-contact and nodding,
found through previous research in HRI. The rules for selecting communicative units were retrieved through our preliminary
experiments with a WOZ method. An experiment was conducted to verify the effectiveness of the robot, with the results revealing
that a robot displaying cooperative behavior received the highest subjective evaluation, which is rather similar to a human
listener. A detailed analysis showed that this evaluation was mainly due to body movements as well as utterances. On the other
hand, subjects' utterance to the robot was encouraged by the robot's utterances but not by its body movements. 相似文献
1000.
H. Ishiyama T. Ishikawa T. Hashimoto Y.X. Watanabe Y. Hirayama N. Imai H. Miyatake M.H. Tanaka Y. Fuchi N. Yoshikawa S.C. Jeong H. Kawakami I. Katayama T. Nomura S. Mitsuoka K. Nishio M. Matsuda P.K. Saha H. Ikezoe S.K. Das Y. Mizoi T. Fukuda 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2006,560(2):366-372
Low-energy (1–2 MeV/nucleon) radioactive nuclear beams (RNBs) of 8Li, 12B and 16N have been produced through nuclear transfer reactions using a recoil mass separator (RMS) at Japan Atomic Energy Research Institute (JAERI). The contamination of the primary beam to the RNB was investigated quantitatively and was well suppressed. The typical beam intensities of 8Li-, 12B- and 16N-RNB were 1.4×104, 7.8×103 and , respectively. Their purities were 99%, 98% and 98.5%, respectively. 相似文献