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51.
Suga K Mochizuki N Yamashita H 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2004,45(5):255-258
A simple method for analysis of fumonisin B1 (FB1) and fumonisin B2 (FB2) in beer and raw materials of beer using liquid chromatography-electrospray ionization tandem mass spectrometry (LC/MS/MS) was developed. Samples were prepared and purified by using solid-phase extraction columns (SAX). The LC separation was performed with an octadecylated silica column at a flow-rate of 0.2 mL/min, using a mobile phase consisting of water and acetonitrile. MS/MS was used in multiple reaction monitoring, employing electrospray ionization (ESI-MRM). Recoveries of spiked FB1 and FB2 from beer were 64% and 52%, respectively, at the level of 5 microg/kg. Recoveries of spiked FB1 and FB2 from malt, cornstarch, and corn grit, at the level of 50 microg/kg, were 87.9% and 86.4%, 89.5% and 87.9%, 86.6% and 81.1%, respectively. This method may have applications in quality assurance. 相似文献
52.
Matsui J Akamatsu K Nishiguchi S Miyoshi D Nawafune H Tamaki K Sugimoto N 《Analytical chemistry》2004,76(5):1310-1315
A molecularly imprinted polymer with immobilized Au nanoparticles (Au-MIP) is reported as a novel type of sensing material. The sensing mechanism is based upon the variable proximity of the Au nanoparticles immobilized in the imprinted polymer, which exhibits selective binding of a given analyte accompanied by swelling that causes a blue-shift in the plasmon absorption band of the immobilized Au nanoparticles. Using adrenaline as the model analyte, it was shown that molecular imprinting effectively enhanced the sensitivity and selectivity, and accordingly, Au-MIP selectively detects the analyte at 5 microM. The combination of molecular imprinting and the Au nanoparticle-based sensing system was shown to be a general strategy for constructing sensing materials in a tailor-made fashion due to wide applicability of the imprinting technique and the independence of the sensing mechanism from the analyte recognition system. 相似文献
53.
A novel optical sensor based on spectroscopic measurement of the plasmon absorption of a colloidal gold submonolayer immobilized upon a planar waveguide has been developed for label-free detection of biomolecular interactions at the sensor's surface. We fabricated the sensor by locally modifying a 50-microm-thick glass plate with hemoglobin (Hb) and then self-assembling gold colloids from the aqueous solution onto the Hb-modified area of the glass plate. Polychromatic light from a xenon-arc lamp was launched into the thin-film glass plate by use of a broadband fiber-coupling method. With the use of a CCD detector to monitor the light beam emitted from an end face of the glass plate, the plasmon absorption spectrum of the colloidal gold submonolayer was determined to depend on the polarization states of the guided light and to change with the refractive index of the medium in contact with the colloids. In addition to simplicity of fabrication and the ease of use, the sensor yields a larger absorbance sensitivity than the normal transmission measurement. 相似文献
54.
Useless-variable elimination is a transformation that eliminates variables whose values does not affect the result of a computation. We present a type-based method for useless-variable elimination and prove its correctness. The algorithm is a surprisingly simple extension of the usual type-reconstruction algorithm. Our method has several attractive features. First, it is simple, so that the proof of the correctness is clear and the method can be easily extended to deal with a polymorphic language. Second, it is efficient: for a simply-typed -calculus, it runs in time almost linear in the size of an input expression. Moreover, our transformation is optimal in a certain sense among those that preserve well-typedness, both for the simply-typed language and for an ML-style polymorphically-typed language. 相似文献
55.
Z. Li T. Schram L. Pantisano A. Stesmans T. Conard S. Shamuilia V.V. Afanasiev A. Akheyar S. Van Elshocht D.P. Brunco W. Deweerd Y. Naoki P. Lehnen S. De Gendt K. De Meyer 《Microelectronics Reliability》2007,47(4-5):518
A systematic study of the flat-band voltage (Vfb) shift of Ru gated metal-oxide-semiconductor (MOS) capacitors subjected to thermal treatment in O2 has been performed. The dependence of the Vfb shift on the thickness of Ru, anneal temperature and time is studied. The Vfb shift is ascribed to the shift of metal gates’ work function (WF), and is not significantly dependent on the type of dielectric (HfO2 or SiO2). From time-of-flight secondary ion mass spectrometry (TOF-SIMS) measurement, it was found that after thermal treatment in 18O2, 18O penetrated through Ru and was incorporated in the Ru/dielectric interface region. We believe that the formation of the thin interfacial RuOx layer is responsible for the Vfb shift. 相似文献
56.
Naoki Mizuno Kazunori Ohno Ryunosuke Hamada Hiroyoshi Kojima Jun Fujita Hisanori Amano 《Advanced Robotics》2013,27(14):687-698
The firefighting robot system (FFRS) comprises several autonomous robots that can be deployed to fire disasters in petrochemical complexes. For autonomous navigation, the path planner should consider the robot constraints and characteristics. Specifically, three requirements should be satisfied for a path to be suitable for the FFRS. First, the path must satisfy the maximum curvature constraint. Second, it must be smooth for robots to easily execute the trajectory. Third, it must allow reaching the target location in a specific heading. We propose a path planner that provides smooth paths, satisfy the maximum curvature constraint, and allows a suitable robot heading. The path smoother is based on the conjugate gradient descent, and three approaches are proposed for this path planner to meet all the FFRS requirements. The effectiveness of these approaches is qualitatively and quantitatively evaluated by examining the generated paths. Finally, the path planner is applied to an actual robot to verify the suitability of the generated paths for the FFRS, and planning is applied to another type of robot to demonstrate the wide applicability of the proposed planner. 相似文献
57.
58.
Chinatsu Yonezawa Masahiro Negishi Kenta Azuma Manabu Watanabe Naoki Ishitsuka Shigeo Ogawa 《International journal of remote sensing》2013,34(18):5696-5711
Spaceborne synthetic aperture radar (SAR) can be used for agricultural monitoring. In this study, three single-polarimetric and four full-polarimetric observation data sets were analysed. A rice paddy field in northern Japan was used as the study site; the data for this site were obtained using RADARSAT-2, which carries a full-polarimetric C-band SAR. Soybean and grass fields were also present within the paddy fields. The temporal change in the backscattering coefficient of the rice paddy fields for the single-polarization data agreed with the temporal change obtained for a rice growth model based on radiative transfer theory. A three-component decomposition approach was applied to the full-polarimetric data. With each rice growth stage, the volume scattering component ratio increased, whereas the surface scattering component ratio generally decreased. The soybean and grass fields showed a smaller double-bounce scattering component than the rice fields for all the acquired data. The results of this study show that multitemporal observation by full-polarimetric SAR has great potential to be utilized for estimating rice-planted areas and monitoring rice growth. 相似文献
59.
Detection of genetically modified organisms in foreign-made processed foods containing corn and potato 总被引:1,自引:0,他引:1
Monma K Araki R Sagi N Satoh M Ichikawa H Satoh K Tobe T Kamata K Hino A Saito K 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2005,46(3):79-85
Investigations of the validity of labeling regarding genetically modified (GM) products were conducted using polymerase chain reaction (PCR) methods for foreign-made processed foods made from corn and potato purchased in the Tokyo area and in the USA. Several kinds of GM crops were detected in 12 of 32 samples of processed corn samples. More than two GM events for which safety reviews have been completed in Japan were simultaneously detected in 10 samples. GM events MON810 and Bt11 were most frequently detected in the samples by qualitative PCR methods. MON810 was detected in 11 of the 12 samples, and Bt11 was detected in 6 of the 12 samples. In addition, Roundup Ready soy was detected in one of the 12 samples. On the other hand, CBH351, for which the safety assessment was withdrawn in Japan, was not detected in any of the 12 samples. A trial quantitative analysis was performed on six of the GM maize qualitatively positive samples. The estimated amounts of GM maize in these samples ranged from 0.2 to 2.8%, except for one sample, which contained 24.1%. For this sample, the total amount found by event-specific quantitative analysis was 23.8%. Additionally, Roundup Ready soy was detected in one sample of 21 potato-processed foods, although GM potatoes were not detected in any sample. 相似文献
60.
Yoshinobu Lshii Takanori Nagasaki Naoki Igawa Hitoshi Watanabe Hideo Ohno 《Journal of the American Ceramic Society》1991,74(9):2324-2326
Temperature dependence of the Raman spectrum of lithium oxide single crystal has been measured over a temperature range of 80 to 1073 K. The frequency shift and the line width of the Raman spectrum in lithium oxide were about 531 and 4.5 cm-1 at 80 K, respectively. At 1073 K, the frequency shift and the line width attained the values of 464 and 112 cm-1 , respectively. The strong temperature dependence of the frequency shift and line width was compared with data from some crystals with a fluorite structure. 相似文献