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51.
This paper presents a fabrication method of three-dimensional micro-structures consisting of high aspect ratio inclined micro-pillars using simple photolithography. The width and height of micro-pillars were 10 m and 200 m (the aspect ratio was about 20). The SU-8 coated on the Cr patterned Pyrex glass substrate was exposed from the backside with an angle to fabricate inclined micro-pillars. The 3-D micro-structures were fabricated by repeating the backside exposure with different angles. The shape of the micro-structure was defined by the number of exposures and the UV irradiation angles. The complicated micro-structures were fabricated by multi-angle exposures around two axes, as well as around one axis.This work was supported by: the Japanese Ministry of Education, Culture, Sport, Science and Technology Grant-in-Aids for COE Research of Waseda University, Scientific Research Priority Area (B) No. 13124209, Japan Society for the Promotion Science Grant-in-Aids for Creative Scientific Research No. 13BS0024, Nanotechnology Support Project of the Ministry of Education, Culture, Sports, Science and Technology (MEXT) Japan, 21COE Practical Nano-Chemistry from MEXT Japan and Waseda University Grant for Special Research Project Individual Research No. 2002A-865. 相似文献
52.
A radio frequency (RF) telemetry system with a shape memory alloy microelectrode was designed and fabricated. The total size and weight are 15 mm x 8 mm and 0.1 g, respectively. Since the telemeter is small and light enough to be loaded on a small animal such as an insect, the system can be used for the neural recording of a freely moving insect. The RF-telemeter can transmit signals by frequency modulation transmission at 80-90 MHz. The transmitted signals can be received up to about 16 meters away from the telemeter with a high signal-to-noise ratio. The neural activity can be detected without attenuation by using an instrumentation amplifier with its input impedance set to 2 Mohms at 1 kHz. The telemeter was loaded on a cockroach and the neural activity during a free-walk was successfully measured through this telemetry system. 相似文献
53.
Finite impulse response (FIR) filters and finite impulse response matrix (FIRM) filters are evaluated for use in the detection of volatile organic compounds with wide spectral bands by direct analysis of interferogram data obtained from passive Fourier transform infrared (FT-IR) measurements. Short segments of filtered interferogram points are classified by support vector machines (SVMs) to implement the automated detection of heated plumes of the target analyte, ethanol. The interferograms employed in this study were acquired with a downward-looking passive FT-IR spectrometer mounted on a fixed-wing aircraft. Classifiers are trained with data collected on the ground and subsequently used for the airborne detection. The success of the automated detection depends on the effective removal of background contributions from the interferogram segments. Removing the background signature is complicated when the analyte spectral bands are broad because there is significant overlap between the interferogram representations of the analyte and background. Methods to implement the FIR and FIRM filters while excluding background contributions are explored in this work. When properly optimized, both filtering procedures provide satisfactory classification results for the airborne data. Missed detection rates of 8% or smaller for ethanol and false positive rates of at most 0.8% are realized. The optimization of filter design parameters, the starting interferogram point for filtering, and the length of the interferogram segments used in the pattern recognition is discussed. 相似文献
54.
Characterization of the chemical conversion films that form on Mg−Al alloy in colloidal silica solution 总被引:1,自引:0,他引:1
Seong?-Jong?KimEmail author Ying?Zhou Ryoichi?Ichino Masazumi?Okido Shoji?Tanikawa 《Metals and Materials International》2003,9(2):207-213
Chemical conversion treatment of Mg−Al alloy (AZ91) using colloidal silica as an alternative to chromate conversion was investigated
as a function of solution pH, temperature, solution conditions, and treatment time. The solution used for the colloidal silica
coating consisted of colloidal silica, titanium sulfate, and cobalt ions to maintain good anti-corrosion and adhesion properties.
Adding CoSO4 to the colloidal silica solution enhanced the adhesion force between the silica film and magnesium substrate. The optimum
conditions for the chemical conversion treatment solution were pH 2, 90-sec treatment, and 25°C. 相似文献
55.
Thiamine is presently one of the most attractive substrates used for sensitive fluorometric measurements of peroxides. Thiochrome (TC), a highly fluorescent product, is formed in enzyme-mediated oxidations. It is assumed that H(2)O(2) is nearly quantitatively converted to TC. The reaction cannot differentiate H(2)O(2) from many other peroxides such as methylhydroperoxide (MHP); to perform differential measurements, H(2)O(2) can first be selectively destroyed by a suitable catalyst such as MnO(2). In substituting Ag(2)O for MnO(2) to accomplish the selective destruction of H(2)O(2), we achieved the stated objective but were puzzled by a 3-fold increase in the MHP response in the presence of Ag(2)O. It was soon discovered that traces of dissolved Ag(+) and Hg(2+) can dramatically increase the yield of TC in this reaction from either H(2)O(2) or MHP; the normal yield in fact is only 20%. We present here a reaction scheme and kinetic model that adequately describes this behavior and should provide a path to substantially increase the sensitivity of this important assay method. 相似文献
56.
A service provisioning system for distributed personalization with private data protection 总被引:1,自引:0,他引:1
Personalized services can provide significant user benefits since they adapt their behavior to better support the user. Personalized services use a variety of data related to the user to decide their behavior. Thus personalized service needs a provisioning system that can collect the data that impacts service behavior and allows selection of the most appropriate service. However, in the coming ubiquitous environment, some data necessary for determining service behavior might be unavailable due to two possible reasons. One is that the data does not exit. The other is that the data exists but cannot be accessed. For example, users do not want to disclose their personal information, and service providers do not also want to expose data related to their knowhow in services. This paper describes a new service provisioning system for distributed personalization with private data protection. Specifically, the system selects applicable services by assessing how well each candidate service behaves when some data is missing. It then executes those selected services while hiding the users’ and providers’ private data in a distributed manner. We first summarize the requirements for a personalized service system, and introduce our fundamental policies for the system. The two main components of our system are then described in detail. One component is a service assessment mechanism that can judge if a service can work without data that can be used for adaptation. The second component is a service execution mechanism that can utilize private data while still ensuring privacy. This component divides service logic and executes divided logic where necessary data is available. The paper finally describes our prototype implementation and its performance evaluation results. 相似文献
57.
58.
In this article, we report the influence of the polyimide molecular weight (1.2 × 105, 2.6 × 105, and 4.1 × 105) on the structure and the gas permeation properties of asymmetric polyimide membranes made by the dry–wet phase‐inversion process. The apparent skin layer thickness of the asymmetric membrane increased with increasing molecular weight, and the thicknesses of the membranes prepared from the three polyimides with a casting polymer solution containing 8.0 wt % butanol were 132, 350, and 739 nm, respectively. That is, the gas permeance in the asymmetric membranes increased with decreasing molecular weight. In contrast, the gas selectivity of the asymmetric membranes did not depend on the skin layer thickness. The solvent evaporation in the dry phase‐inversion process and the nonsolvent diffusion in the dry process were important factors that determined the formation of the asymmetric membrane. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
59.
60.
Takashi Itoh Hitoe Habuchi Shoji Nitta Shuichi Nonomura 《Fullerenes, Nanotubes and Carbon Nanostructures》1994,2(2):181-187
Gas effusion spectra of fullerenes are studied. Three peaks of toluene are found in gas effusion spectra dp/dT-T. Two peaks of oxygen are found in gas effusion spectra dN/dt-T of samples kept in the air after annealing to avoid the toluene. These phenomena confirmed to be reversible are discussed by treating fullerenes as intercalated materials. 相似文献