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81.
Increasingly, multi-agent systems are being designed for a variety of complex, dynamic domains. Effective agent interactions in such domains raise some of the most fundamental research challenges for agent-based systems, in teamwork, multi-agent learning and agent modelling. The RoboCup research initiative, particularly the simulation league, has been proposed to pursue such multi-agent research challenges, using the common testbed of simulation soccer. Despite the significant popularity of RoboCup within the research community, general lessons have not often been extracted from participation in RoboCup. This is what we attempt to do here. We have fielded two teams, ISIS97 and ISIS98, in RoboCup competitions. These teams have been in the top four teams in these competitions. We compare the teams, and attempt to analyze and generalize the lessons learned. This analysis reveals several surprises, pointing out lessons for teamwork and for multi-agent learning.  相似文献   
82.
The key objectives of this study were to evaluate the use of an alternating current (AC) for the degradation of naphthalene in spiked aqueous solutions and to investigate the effect of current density on the degradation rates of naphthalene. Direct current (DC) was also used to compare the rates of degradation. Sodium chloride (NaCl) and anhydrous sodium sulfate (Na2SO4) were used as the supporting electrolytes. Degradation rates and byproducts formed were investigated when DC and AC were separately passed through naphthalene solutions. A square wave AC, having a frequency equal to 0.1?Hz was used. Naphthalene solutions having an initial concentration of about 20?mg/L ( ~ 0.15?mM) were subjected to an AC peak current density and DC density of 6?mA/cm2, using NaCl as the supporting electrolyte. An approximate 65% reduction in the concentration of naphthalene was observed after a period of 48 h when DC was applied. Degradation was almost 100% when the AC was applied during the 48-h period. The effect of current density on the electrochemical degradation rate of naphthalene in aqueous solution was also investigated at alternating and direct current densities of 1, 3, and 6?mA/cm2 using Na2SO4 as the supporting electrolyte. AC peak current densities of 1, 3, and 6?mA/cm2 resulted in overall conversions of 77, 87, and 95%, respectively, of naphthalene in solution. The corresponding values for DC application were 95% for all current densities while the initial degradation rates were greater at higher DC densities. Based on the degradation products formed, hydroxylation is believed to be the key mechanism for the degradation of naphthalene.  相似文献   
83.
The relative amounts of oil and gas produced in prolific plays like the Eagle Ford are affected by the oil bubble point. The oil and kerogen (organic matter) are found in the same rock and the oil may remain in contact with the kerogen. Bulk experiments and molecular simulations clearly show that kerogen preferentially absorbs hydrocarbons. The absorbed oil phase remains in multi‐component equilibrium with the expelled oil produced at the surface. Results from a model proposed to calculate the bubble points (at 400 K) of in situ oils (absorbed + free) in the presence of kerogen indicate suppression of about 4150–16,350 kPa from the original value of 28,025 kPa of produced Eagle Ford oil. These calculations depend on the type and level of maturity of kerogen. The prediction of accurate saturation pressures has key implications on volumes of recovery and rates of production from liquid rich shales. © 2017 American Institute of Chemical Engineers AIChE J, 63: 3083–3095, 2017  相似文献   
84.
A conducting polymer, polyaniline, was synthesized by chemical polymerization using different inorganic acids, such as HCl, H2SO4, HClO4, HNO3, and H3PO4, as protonic acid media. The synthesized polymers were characterized using UV‐visible and FT‐IR spectroscopy. A granular type of morphology was observed under SEM for HCl, HNO3, and H3PO4 doped polyanilines. However, HClO4 doped polyaniline shows the folded lamellar structure derived from the fibers. The thermal stability of these polymers was investigated with the help of thermogravimetric (TG/SDTA) analysis. The formation of a greater fraction of the conducting emeraldine salt phase is observed in HClO4 as a protonic acid media. The thermal stability of H3PO4 doped material is found to be better as compared with other acids. An increase in conductivity with an increase in temperature was observed in all the samples except for HClO4 doped polyaniline. Polym. Eng. Sci. 44:1676–1681, 2004. © 2004 Society of Plastics Engineers.  相似文献   
85.
The majority of semiconductors are built on silicon wafers. Future semiconductors will require flatter wafers with a lower price. The lapping-based manufacturing method currently used to manufacture silicon wafers will not be able to meet the ever-increasing demand cost-effectively. This paper reports an experimental investigation into a grinding-based manufacturing method, which has potential to manufacture flat silicon wafers at a lower cost. Background information on semiconductors and silicon wafers is presented first. After a discussion on drawbacks of the lapping-based method, the grinding-based method is described. Next, experimental results with the grinding-based method are presented and discussed. The results from this investigation have demonstrated the potential of the grinding-based method and revealed several directions for future work.  相似文献   
86.
Clean Technologies and Environmental Policy - Development of environmentally benign green processes for utilization of carbon dioxide to synthesize value-added compounds using heterogeneous...  相似文献   
87.
本文提出了一种预测IC热性能的方法。这些信息对于汽车及其它高温环境下使用的PMIC(电源管理IC)尤为有用。通过分析热性能,我们设计了一种数学模型用于仿真芯片内部的瞬态温度。并引入了关  相似文献   
88.
The controlled presentation of proteins from and within materials remains of significant interest for many bioengineering applications. Though “smart” platforms offer control over protein release in response to a single external cue, no strategy has been developed to trigger delivery in response to user‐specified combinations of environmental inputs, nor to independently control the release of multiple species from a homogenous material. Here, a modular semisynthetic scheme is introduced to govern the release of site‐specifically modified proteins from hydrogels following Boolean logic. A sortase‐mediated transpeptidation reaction is used to generate recombinant proteins C‐terminally tethered to gels through environmentally sensitive degradable linkers. By varying the connectivity of multiple stimuli‐labile moieties within these customizable linkers, YES/OR/AND control of protein release is exhaustively demonstrated in response to one and two‐input combinations involving enzyme, reductant, and light. Tethering of multiple proteins each through a different stimuli‐sensitive linker permits their independent and sequential release from a common material. It is expected that these methodologies will enable new opportunities in tissue engineering and therapeutic delivery.  相似文献   
89.
90.
ABSTRACT

The proton and carbon-13 nuclear magnetic resonance characteristics of the native Whiterocks bitumen were determined by comparing the spectra of the samples to literature assignments. The tentative structural assignments of pyrolysis products were also obtained from the spectra of Curie-point low voltage mass spectrometric analysis. The results obtained from proton and carbon-13 nuclear magnetic resonance and pyrolysis-mass spectrometry analysis suggested that the native bitumen consists mostly of short- and long-chain (i.e., normal and isoprenoid chains) alkylsubstituents attached to polycyclic naphthenic, naphtheno-aromatic and/or aromatic moieties.  相似文献   
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