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排序方式: 共有493条查询结果,搜索用时 15 毫秒
111.
We fabricated new 2.78‐in 1058‐ppi organic light‐emitting diode (OLED) displays. The displays used OLED devices with a tandem structure and a single structure and a field effect transistor (FET) using c‐axis aligned crystalline In–Ga–Zn–O (CAAC‐IGZO) for an active layer and employing the 1.5‐µm rule over a glass substrate. Even in the displays with such high resolution exceeding 1000 ppi, crosstalk that was observed in the lower luminance region was suppressed. The displays achieved high color reproducibility and reduced viewing angle dependence.  相似文献   
112.
One of the major challenges for the NOx Storage and Reduction Catalysts technology used in automotive exhaust remains the sulfur susceptibility, which calls for efficient desulfation strategies. The sulfation and desulfation processes are systematically studied via measurements and mathematical modeling of the physicochemical processes. The role of oxygen storage which influences the reducing agents availability for desulfation is explained and a respective reaction model is presented. The bulk oxygen storage component appears to be involved in sulfur storage, which further emphasizes the importance of oxygen–sulfur storage interactions. Next, the observed release of sulfur species under lean mode is discussed along with a proposed reaction mechanism which involves SO2 formation via O2 reaction with elemental sulfur on the surface. The parameters of the complex reaction model are calibrated in order to reproduce the observed trends at least in a qualitative manner. © 2016 American Institute of Chemical Engineers AIChE J, 63: 2117–2127, 2017  相似文献   
113.
The macroscopic particle model (MPM) based on the finite volume method is employed to validate a mechanism of lift force-induced particle separation in a curved microchannel. According to the particle velocity at each time step in the unsteady simulation, the MPM gives momentum to those fluid cells touching the particle physical boundary. The summation of the given momentum with the reversed sign is divided by the time step to obtain the hydrodynamic force acting on the particle. Namely, the existence and motion of the particle causes fluid flow around the particle, while the flow field caused by the particle determines the particle motion by means of the hydrodynamic force. Therefore, the MPM can be regarded as implementing a quasi-direct numerical simulation over the static computational cells. The lift force acting on a spherical particle in a shear flow is a purely hydrodynamic force caused by the flow field around the particle. It is expected, therefore, that the MPM could predict the lift force effect without any additional model. At first, it is shown that the MPM is capable of predicting particle migration away from the wall of a straight microchannel due to the lift force. In a curved microchannel, subsequently, the particle trajectories from representative release points predicted by the MPM are compared to those predicted by a common particle tracking method without any lift force model. The MPM predicted that the particle trajectories are confined in the outer region of the channel cross-section. On the other hand, the circulating trajectories predicted by the tracking method tend to expand due to centrifugal force caused by the Dean vortices. It is concluded, therefore, that the lift force due to the steep shear rate is a significant factor to cause particle separation in a curved microchannel.  相似文献   
114.
Glassy microspheres containing a rare earth are attractive for practical use as microcavities for morphology-dependent resonances (MDRs). However, no efficient and low-cost mass-production process has been established for such microcavities. In the present study, we have synthesized glassy microcavities through liquid–liquid phase separation of alkaline-earth borate glass. Glassy microspheres have been prepared by the liquid–liquid phase separation of BaO-B2O3 glasses, by controlling the particle size within the range 1–45 μm and the size distribution within 1%. The microspheres show periodic, sharp peaks, indicative of MDRs, in their Raman-scattering spectra and in the fluorescence spectra of the internal rare earth. These microspheres act as high-quality microcavities, with Q factors comparable to those calculated using the Lorenz–Mie theory.  相似文献   
115.
We applied a gas chromatography-mass spectrometry (GC-MS) method using dimethyl disulfide (DMDS) adducts and were able to determine the double-bond positions in monounsaturated 2-hydroxy fatty acids (2-HFA). 2-HFA methyl esters, prepared from the hydrolysate ofArabidopsis thaliana leaf glucosylceramides, were acetylated and methylthiolated. GC-MS analysis of the resulting DMDS adducts showed simple mass spectra with recognizable molecular ions and a series of key fragment ions indicating the original double-bond positions in the aliphatic chain. Based on this GC-MS elucidation, we confirmed thatArabidopsis leaf glucosylceramides have C22, C23, C24, C25, and C26 chain length 2-HFA with monounsaturation, and all their double bonds are placed at the n−9 position. This procedure is simple, time efficient, and highly sensitive.  相似文献   
116.
A catalyst containing gold nanoparticles with Pt/α-Fe2O3/C was prepared by a co-precipitation method and its catalytic activity for the oxidation of methanol, formaldehyde, and formic acid in alkaline solutions was evaluated by an electrochemical method and high-performance liquid chromatography (HPLC). The addition of gold nanoparticles improved catalytic activity only for the oxidation of methanol and formaldehyde, and not for the oxidation of formic acid. HPLC analysis was performed for methanol oxidation to detect the oxidative products. In HPLC analysis, only formate anion could be detected in the electrolyte solution and the ratio of formate anion obtained to the total passed charge in Pt/nano-Au/α-Fe2O3/C was less than that in Pt/C, indicating that formic acid is not the final product of methanol oxidation. These results show that gold nanoparticles promoted methanol oxidation up to CO2.  相似文献   
117.
cis-Vaccenic acid in mango pulp lipids   总被引:1,自引:3,他引:1  
A peak corresponding to a methyl octadecenoate other than oleate has been detected on the capillary gas chromatogram of the methyl esters of mango pulp fatty acids. This octadecenoate was isolated by silica gel and argentation column chromatography, high performance liquid chromatography and argentation thin layer chromatography, and then analyzed by infrared, nuclear magnetic resonance and gas chromatography-mass spectrometry, chromatographic separations and oxidative degradation. These analytical data proved that the octadecenoic acid wascis-vaccenic acid (cis-11-octadecenoic acid). The concentration of this acid in total octadecenoic acids ranged from 35% to 50% in the pulp of mangoes from Fiji, Mexico, the Philippines and Taiwan.cis-Vaccenic acid was revealed to be one of the major component fatty acids of non-polar lipids (mainly triacylglycerols), glycolipids and phospholipids in mango pulp. The glycolipids containedcis-vaccenic acid (ca. 20%) in higher concentration than oleic acid (ca. 15%). A trace amount ofcis-vaccenic acid (0.5%) was detected in the total lipids of mango seeds. Profile of fatty acid composition of mango pulp lipids (0.2–0.3 wt% of wet pulp) was characterized by the presence of n−7 acid isomers,cis-vaccenic acid and palmitoleic acid, and unusual mono- and dienoic positional isomers.  相似文献   
118.
We have developed a novel super fast response (SFR) thin‐film transistor liquid crystal display (TFT‐LCD) with an extremely wide temperature range. Nematic liquid crystal molecules with positive dielectric anisotropy are vertically aligned initially. Any gray‐to‐gray response is forcibly controlled by applying an electric field. Response times of the SFR TFT‐LCD are over several times shorter than those of conventional LCDs such as vertical alignment or in‐plane switching LCDs.  相似文献   
119.
Traditional studies on measurements and training of teamwork have often focused on observational teamwork behaviors; however, measurements and training of unobservable teamwork such as mutual performance monitoring are also important for improving teamwork measurement and training. In addition, an improvement of cognitive mechanisms underlying teamwork must effectively be able to enhance team performance because sufficient situation awareness of status of team is expected to be a requirement for positive teamwork behaviors. This study focuses on metacognition in cooperation that underlies team cooperation and aims to investigate the importance of metacognition in cooperation by analyzing contents of reflection on cooperation collected in our previous study in terms of our proposed model about metacognition in cooperation. The comparisons of metacognition in cooperation elicited in a team experiment and team performance indexes suggest that an expansion of range of metacognition in cooperation by metacognitive instructions will enhance team performance and that certain types of metacognition in cooperation are important for positive teamwork.  相似文献   
120.
Vertical Si nanowires with ultra-high-aspect-ratio were fabricated using a combined process of deep reactive ion etching and sacrificial oxidation. The combined process starts with etching the Si substrates by the Bosch process to form micrometer-scale structures. The etched micrometer-scale structures are shrunk to nanometer-scale by sacrificial oxidation. The fabricated Si nanowires that were aligned vertically to the substrate had a diameter of less than 200 nm and a length greater than 10 μm. One of the fabricated Si nanowires had a diameter of 110 nm and a length of 11 μm. The resulting aspect-ratio reached 100, which is a value that is significantly high for vertical Si nanowires fabricated by using a top-down approach.  相似文献   
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