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21.
不同扫描方式南果梨近红外模型差异性研究   总被引:1,自引:0,他引:1  
依据近红外光谱原理,分别以不同的扫描方式对南果梨样品进行光谱扫描,并对80个南果梨样品分别建立可溶性固形物(SSC)、有效酸度(pH)模型,模型的相关系数和校正集标准偏差均达到应用要求,应用所建模型对20个已知成分含量的南果梨进行可溶性固形物和有效酸度的预测,预测值方差分析结果表明模型间有显著差异,确定180°转动扫描2次(正反两面扫描两次)条件下建立的模型为最佳.  相似文献   
22.
Two predominant perfluorinated compounds (PFCs), Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), in surface water (SW, 0-20 cm), subsurface water (SSW, > 30 cm depth), and sea surface microlayer (SML, 50 microm thickness) were measured from Dalian Coastal waters in China. The SML samples were collected using glass-plate dipping method. Analysis of the PFCs was conducted through solid-phase extraction, followed by LC/MS-SIM. The PFC's concentrations in SW samples were consistent with previously reported data in this region. Significantly higher concentrations of PFCs were found in SML samples than corresponding SSW samples. The enrichment factors (EF = C(SML)/C(SSW)) for PFOS were as high as 24-109 atthree near-shore sites. The concentration in SW was also generally higher than corresponding SSW samples, giving C(SW)/C(SSW) mean ratios of 1.5 and 1.4 for PFOS and PFOA, respectively. This apparent enrichment of PFCs in surface water, especially in the microlayer, has implications for designing measurement techniques, understanding their distributions, and sea spray-mediated transport in the environment.  相似文献   
23.
The purpose of this research is to characterize the cryogenic delamination growth behavior in woven glass fiber reinforced polymer (GFRP) composite laminates subjected to Mode II fatigue loading. Mode II fatigue delamination tests were performed at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K) using the four-point bend end-notched flexure (4ENF) test method, and the delamination growth rate data for the woven GFRP laminates were obtained. The energy release rate range was determined by the finite element method. Microscopic examinations of the specimen sections and fracture surfaces were also carried out. The present results are discussed to obtain an understanding of the fatigue delamination growth mechanisms in the woven GFRP laminates under Mode II loading at cryogenic temperatures.  相似文献   
24.
An input system for CAD is developed to construct a part model within a computer from a hand-written sketch. The sketch is drawn based on the technical illustration method. The shape of the input part is constructed by the combination of cuboids and cylinders at present. A coloured illustration is adopted for the ease of the shape recognition and for the input of the technological information.

The illustration is fed into the computer via a black and white ITV. Colours are identified referring to the brightness of the input image. The constitutive bodies, the geometric element with the technological information and the content of the technological information are recognized through image processing such as noise filtering, thinning of the contours, detection of lines and so on. The input system outputs a set of commands to the modelling system. The integrated part model which includes not only the geometrical information but also the technological information of the part is constructed by the connected modelling system CIMS/MODE.

The combination of the input system and the modelling system can support the designer to construct the detailed part model within the computer effectively. It is expected to extend the ability of the input system to identify general hand-written illustrations so that the input method will be more practical and useful.  相似文献   

25.
Temperature-sensitive hydrogel beads were prepared by Kenics static mixer technology. The temperature-sensitive monomer N,N-diethylacrylamide and photo-crosslinkable pre-polymer ENT were used as model hydrogel materials. Drop dispersion of high viscosity polymer material in low viscosity hexadecane was made using the static mixer. Drops of a solution of the mixed materials were rapidly photo-crosslinked by UV irradiation after mixing in the static mixer, and spherical hydrogel beads with narrow, normal size distribution were thus prepared. The Kenics static mixer is a useful device for the preparation of spherical beads of temperature-sensitive hydrogels. The Sauter Mean Diameter of the hydrogel beads swollen in deionized water at 293 K was measured. The experimentally determined dimensionless swollen hydrogel bead diameter was well correlated with the Weber number, degree of swelling and viscosity ratio. The effects of gelation and ENT addition on the bead size were evaluated from the degree of swelling. The correlation equation can be used for size adjustment of temperature-sensitive spherical hydrogel beads.  相似文献   
26.
In order to increase the Q‐factor of an RF spiral inductor used in the RF front‐end circuit of smartphone handsets, we introduced a carbonyl‐iron/epoxy composite magnetic core in the air‐core spiral inductor. The composite magnetic core, which was made by metal‐mask printing, consisted of carbonyl‐iron powder of 1.1 μm mean diameter and an epoxy resin matrix. We found that the 45 vol.% CIP composite magnetic core had a saturation magnetization of 0.9 T, relative permeability of ∼6, and loss tangent (tan δ) of ∼0.2 at 1 GHz. A two‐turn copper spiral inductor fabricated with the composite magnetic core filled only in the spacing between the conductor lines showed a clear Q‐factor increase of ∼29% compared to the air‐core spiral inductor at 1 GHz. Thus we obtained a substantial increase in the Q‐factor by the embedded composite magnetic core in the spacing between the conductor lines. The main reason for this is that the magnetic flux passing through the conductor lines was decreased by the magnetic core embedded in the spacing between conductor lines as a result of the magnetic flux passing mainly through the embedded magnetic core. Therefore, proximity effect is suppressed in the conductor line of the spiral coil. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
27.
This paper presents a modeling methodology for unknown disturbances in mechatronics systems, based on disturbance estimation using an iterative learning process. In disturbance modeling, nonlinear frictions are specially handled as disturbances in the mechanisms, which mainly degrade trajectory control performance. Friction can be mathematically modeled by using learned estimation data as a function of the displacement, velocity. acceleration, and jerk of the actuator. This model has the distinctive feature that friction compensation can be achieved with a generalization capability for different conditions. The proposed positioning control approach with disturbance modeling and compensation has been verified by experiments using a table drive system on a machine stand. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(2): 31–39, 2010; Published online in Wiley InterScience ( www. interscience.wiley.com ). DOI 10.1002/eej.20928  相似文献   
28.
In this paper, CMOS‐based low‐noise amplifiers with JFET‐CMOS technology for high‐resolution sensor interface circuits are presented. A differential difference amplifier (DDA) configuration is employed to realize differential signal amplification with very high input impedance, which is required for the front‐end circuit in many sensor applications. Low‐noise JFET devices are used as input pair of the input differential stages or source‐grounded output load devices, which are dominant in the total noise floor of DDA circuits. A fully differential amplifier circuit with pure CMOS DDA and three types of JFET‐CMOS DDAs were fabricated and their noise performances were compared. The results show that the total noise floor of the JFET‐CMOS amplifier was much lower compared to that of the pure CMOS configuration. The noise‐reduction effect of JFET replacement depends on the circuit configuration. The noise reduction effect by JFET device was maximum of about − 18 dB at 2.5 Hz. JFET‐CMOS technology is very effective in improving the signal‐to‐noise ratio (SNR) of a sensor interface circuit with CMOS‐based sensing systems. © 2008 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
29.
30.
ABCD1 is a gene responsible for X‐linked adrenoleukodystrophy (X‐ALD), and is critical for the transport of very long‐chain fatty acids (VLCFA) into peroxisomes and subsequent β‐oxidation. VLCFA‐containing lipids accumulate in X‐ALD patients, although the effect of ABCD1‐deficiency on each lipid species in the central nervous system has not been fully characterized. In this study, each phospholipid and lysophospholipid species in Abcd1‐deficient mice brains were profiled by liquid chromatography‐mass spectrometry. Among the phospholipid and lysophospholipid species that are significantly more enriched in Abcd1‐deficient mice brains, VLCFA were present in 75, 15, 5, 4, and 1 species of phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, lysophosphatidylcholine, and lysophosphatidylethanolamine, respectively. Most VLCFA were incorporated at the sn‐1 position of phosphatidylcholine and phosphatidylethanolamine. Among the phospholipid species that are significantly less enriched in Abcd1‐deficient mice brains, odd‐numbered saturated or mono‐unsaturated fatty acyl moieties are contained in all phosphatidylcholine species. In addition, a number of phosphatidylglycerol, phosphatidylinositol, and phosphatidylserine species contained highly unsaturated fatty acyl moieties. Intriguingly, 44:1 phosphatidylcholine with VLCFA was mainly distributed in the gray matter, such as the cortex, but not in the white matter in the cerebrum and cerebellum. These results show that ABCD1‐deficiency causes metabolic alternation of long‐chain fatty acids and VLCFA. Moreover, our results imply a molecular mechanism for the incorporation of saturated or monounsaturated VLCFA into the sn‐1 position of phospholipids, and also indicate that the distribution of phospholipids with VLCFA may correlate with the development of X‐ALD.  相似文献   
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