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101.
In the current paper, we propose a new online search, fault detection, and fault location approach for short faults in network on chip communication channels. The approach proposed consists of a built-in self-test as well as a packet/flit comparings module embedded in the network adapter and a router, respectively. The approach is mainly characterized by the fact that, firstly, the diagnosis and location processes are simultaneously carried out after which the test time is minimized. Secondly, the approach updates the NoC routing tables far less costly in a parallel fashion. Thirdly, insignificant hardware is added to the system. The high scalability in the approach, in addition, leads to 100% test coverage, 71.4% capability of detecting faulty channels, and 100% detected faults location in one round (two phases). The simulation results show that the approach hardware is optimized compared with the previous methodologies.  相似文献   
102.
The Elbow River watershed, located in the rain shadow of the Rocky Mountains in western Canada, is characterized by a complex hydrological regime due to significant differences in climate and geomorphological settings between the west and east sub-catchments. This watershed has experienced several extreme droughts and floods in the recent decades, which might be accentuated with climate change. This study was undertaken to investigate the average annual and seasonal variations of surface and sub-surface hydrological processes in the west and east sub-catchments along with and the entire watershed under five plausible GCM-scenarios up to 2070 using the physically-based, distributed MIKE SHE/MIKE 11 model. Most of the scenarios indicate a reduction in the average annual overland flow, groundwater recharge and baseflow in the east sub-catchment. The pattern of seasonal change generally exhibits a rise in overland flow, baseflow, evapotranspiration, groundwater recharge, and streamflow in winter-spring and a decline in summer-fall. The induced changes in hydrological processes are proportionally more perceptible in the east sub-catchment compared to the west sub-catchment. However, the west sub-catchment governs the watershed behaviour and determines the future changes, over-riding the stronger climate change signal in the east. This investigation indicates that a greater understanding of climate change impacts on the water balance of a watershed with significant differences in sub-regional settings is achieved when capturing the surface and subsurface hydrological process responses of each sub-catchment individually along with the entire watershed. Such information can guide water resources management by providing a more rigorous assessment of the processes involved in the watershed.  相似文献   
103.
104.
In this work, polypropylene/thermoplastic starch (PP/TPS) with and without halloysite nanotubes (HNTs) was prepared via melt mixing in order to obtain environmentally friendly plastics. PP‐grafted maleic anhydride (PP‐g‐MA) was used to improve the compatibility among the highly incompatible polymers. The mechanical characterization showed a reduction in the tensile properties of the polymer when TPS increased; however, HNT successfully compensated for some of the observed losses. The results from the thermogravimetric analysis (TGA) indicated that HNT is an efficient reinforcement for the thermal stability improvement. TPS caused an increase in the storage modulus (G′) and the complex viscosity (η*) which marks a change in the viscoelastic properties of the system. The scanning electron microscope (SEM) images showed the effective plasticization of starch and better dispersion of TPS in the presence of HNT. Some samples were also buried in the soil to measure their sustainability after their lifetime lapse. The results indicated that TPS improves the biodegradability of the PP/TPS system. PP considerably lowered the moisture uptake of TPS; nevertheless, HNT caused a slight increase in the moisture absorption. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45740.  相似文献   
105.
In this work, the parameters of cobalt oxide suspension such as conductivity, zeta potential, particle size, stability, and finally the electrophoretic behavior of particles in the absence and presence of polyethylenimine (PEI) in acetone medium were investigated. Also, the effects of washing on the stability and electrophoretic deposition of Co3O4 were studied. Characterization of the obtained layer by optical microscopy revealed that there was no deposition in the suspension without PEI, while a uniform layer was formed in the presence of PEI additive. Scanning electron microscopy (SEM) results confirmed the uniformity of layer obtained in acetone using PEI additive. Moreover, SEM results demonstrated that more porous microstructures were obtained at longer deposition durations. The difference in the porosity of the layers, as indicated by the SEM micrographs, is attributed to increase in the deposition time.  相似文献   
106.
Two types of chromium catalysts bearing pyridine and amine based SNS ligands under the title of (pyridine-SNS-alkyl/CrCl3) and (amine-SNS-alkyl/CrCl3) were synthesized. Different thiolates such as octyl, pentyl, butyl, cyclohexyl and cyclopentyl thiolates were reacted with 2,6-pyridine-dimethylene-ditosylate (PMT)/THF solution at room temperature. Then, the purified pyridine-based SNS ligands (15) were reacted with CrCl3 (THF)3 to obtain the pyridine-SNS-alkyl/CrCl3 catalysts (610) in 50–70% yields. MMAO-activated pyridine-SNS-alkyl/CrCl3 catalysts were capable of oligomerizing ethylene. Statistical experimental design was conducted using the central composite design method and surface methodology to study of the effect of important parameters such as ethylene pressure, Al/Cr ratio, catalyst concentration and the reaction temperature on 1-C6 productivity of catalyst (7). A quadratic polynomial equation was developed to predict the 1-C6 productivity. Ethylene oligomerization using the catalyst (7) was lead to a optimized reaction conditions, including the ethylene pressure of 19.5 bar, the temperature of 58.2 °C, the MMAO co-catalyst, Al/Cr?=?841 and the catalyst concentration of 8.7 µmol. The catalytic properties for ethylene oligomerization are strongly affected by reaction temperature. The experimental results indicated the reasonable agreement with the predicted values. The transformation from ethylene trimerization to ethylenev polymerization of catalyst system (7) was occurred by exchanging the reaction pressure. Influence of ligand structure with different substitutions on sulphur atom on productivity and selectivity was investigated. 1-C6 with the high selectivity and productivity 4318 (g 1-C6/g Cr h) was obtained for catalyst (7). In the second part, 1-C6 was obtained with high selectivity and productivity around 141?×?103 (g 1-C6/g Cr h) for amine-based catalyst. All amine-based catalysts (1416) showed considerably higher catalytic activities compared to pyridine-based catalysts. According to the TGA analysis the thermal stability of pyridine-based catalysts was found to be higher than the amine-based catalysts.

Graphical Abstract

Chromium complexes bearing pyridine and amine based SNS ligands have been synthesized and their catalytic performance in ethylene oligomerization has been investigated. A switching from ethylene trimerization to ethylene polymerization of the catalyst (7) was obtained utilizing exchanging of the ethylene pressure.
  相似文献   
107.
2D titanium carbides (MXene) possess significant characteristics including high conductivity and electromagnetic interference shielding efficiency (EMI SE) that are important for applications in printed and flexible electronics. However, MXene‐based ink formulations are yet to be demonstrated for proper inkjet printing of MXene patterns. Here, tandem repeat synthetic proteins based on squid ring teeth (SRT) are employed as templates of molecular self‐assembly to engineer MXene inks that can be printed as stimuli‐responsive electrodes on various substrates including cellulose paper, glass, and flexible polyethylene terephthalate (PET). MXene electrodes printed on PET substrates are able to display electrical conductivity values as high as 1080 ± 175 S cm?1, which significantly exceeds electrical conductivity values of state‐of‐the‐art inkjet‐printed electrodes composed of other 2D materials including graphene (250 S cm?1) and reduced graphene oxide (340 S cm?1). Furthermore, this high electrical conductivity is sustained under excessive bending deformation. These flexible electrodes also exhibit effective EMI SE values reaching 50 dB at films with thicknesses of 1.35 µm, which mainly originate from their high electrical conductivity and layered structure.  相似文献   
108.
109.
This paper addresses a fundamental trade-off in dynamic scheduling between the cost of scheduling and the quality of the resulting schedules. The time allocated to scheduling must be controlled explicitly, in order to obtain good-quality schedules in reasonable times. As task constraints are relaxed, the algorithms proposed in this paper increase scheduling complexity to optimize longer and obtain high-quality schedules. When task constraints are tightened, the algorithms adjust scheduling complexity to reduce the adverse effect of long scheduling times on the schedule quality. We show that taking into account the scheduling time is crucial for honoring the deadlines of scheduled tasks. We investigate the performance of our algorithms in two scheduling models: one that allows idle-time intervals to exist in the schedule and another that does not. The model with idle-time intervals has important implications for dynamic scheduling which are discussed in the paper. Experimental evaluation of the proposed algorithms shows that our algorithms outperform other candidate algorithms in several parameter configurations.  相似文献   
110.
近年来,以纳米尺度和纳米颗粒以及定向或随机分布的离散单元(如纤维)来加固土体的材料已被广泛应用于岩土工程中.本研究的主要目的是研究纳米黏土与再生聚酯纤维混合作为一种新的稳定材料对土壤力学行为的影响.对于未强化和三种纤维含量介于0.1%和0.5%的强化土壤标本,以及三种纳米黏土含量介于0.5%和1.5%的土壤进行排干剪切...  相似文献   
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