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71.
A key issue in the field of inclusive design is the ability to provide designers with an understanding of people's range of capabilities. Since it is not feasible to assess product interactions with a large sample, this paper assesses a range of proxy measures of design-relevant capabilities. It describes a study that was conducted to identify which measures provide the best prediction of people's abilities to use a range of products. A detailed investigation with 100 respondents aged 50-80 years was undertaken to examine how they manage typical household products. Predictor variables included self-report and performance measures across a variety of capabilities (vision, hearing, dexterity and cognitive function), component activities used in product interactions (e.g. using a remote control, touch screen) and psychological characteristics (e.g. self-efficacy, confidence with using electronic devices). Results showed, as expected, a higher prevalence of visual, hearing, dexterity, cognitive and product interaction difficulties in the 65-80 age group. Regression analyses showed that, in addition to age, performance measures of vision (acuity, contrast sensitivity) and hearing (hearing threshold) and self-report and performance measures of component activities are strong predictors of successful product interactions. These findings will guide the choice of measures to be used in a subsequent national survey of design-relevant capabilities, which will lead to the creation of a capability database. This will be converted into a tool for designers to understand the implications of their design decisions, so that they can design products in a more inclusive way.  相似文献   
72.
This paper deals with the dynamic output feedback stabilization problem of deterministic finite automata (DFA). The static form of this problem is defined and solved in previous studies via a set of equivalent conditions. In this paper, the dynamic output feedback (DOF) stabilization of DFAs is defined in which the controller is supposed to be another DFA. The DFA controller will be designed to stabilize the equilibrium point of the main DFA through a set of proposed equivalent conditions. It has been proven that the design problem of DOF stabilization is more feasible than the static output feedback (SOF) stabilization. Three simulation examples are provided to illustrate the results of this paper in more details. The first example considers an instance DFA and develops SOF and DOF controllers for it. The example explains the concepts of the DOF controller and how it will be implemented in the closed-loop DFA. In the second example, a special DFA is provided in which the DOF stabilization is feasible, whereas the SOF stabilization is not. The final example compares the feasibility performance of the SOF and DOF stabilizations through applying them to one hundred random-generated DFAs. The results reveal the superiority of the DOF stabilization.  相似文献   
73.
Due to aggressive technology scaling in electronic of digital integrated circuits, the circuit reliability is becoming an ever-increasing challenge. In nanoscale technologies, the physical and chemical properties of materials are fundamentally different compared to the larger scales. Therefore, it is necessary to revise the conventional reliability assessment techniques considering their applicability to nanoscale integrated circuits. This paper presents a method for evaluating the circuit reliability at the transistor level of abstraction considering the physical characteristics of the transistors. The proposed method considers various parameters, including the probability of different types of a transistor failure, the topology of logic gates and the logical values of the applied input vectors. Experimental results show that the proposed approach provides accurate transistor-level circuit reliability evaluations (with < 4% inaccuracy) as compared to a reference method based on Monte Carlo HSPICE simulations in addition to more than 800 times speedup. Moreover, to show the comprehensiveness and extensibility of the proposed reliability analysis method for the technologies beyond conventional MOSFETs, it is applied to carbon nanotube field-effect transistor (CNFET) technology as one of the most promising candidates for future CMOS circuits. The obtained results re-acknowledge that in order to achieve a more accurate reliability estimation approach for CNFET circuits, it is necessary to consider the open and short failure probability values individually instead of considering them in the form of a single transistor failure probability.  相似文献   
74.
The increasing global demands for pure manganese in steel production and manganese compound as dietary additives, fertilizer, pigment, cells and fine chemicals production cannot be over-emphasized. Thus, continuous efforts in developing low cost and eco-friendly route for purifying the manganese ore to meet some defined industrial demands become paramount. Therefore, this study focused on reductive leaching and solvent extraction techniques for the purification of a Nigerian manganese ore containing admixture of spessartine (O96.00Mn24.00Al16.00Si24.00) and quartz (Si3.00O6.00). During leaching, parameters such as leachant concentration and reaction temperature on the extent of ore dissolution were examined accordingly for the establishment of extraction conditions. At optimal leaching conditions (1.5 mol/L H2SO4?+?0.2 g spent tea, 75 °C), 80.2% of the initial 10 g/L ore reacted within 120 min. The derived dissolution activation energy (Ea) of 35.5 kJ/mol supported the diffusion reaction mechanism. Thus, the leachate at optimal leaching was appropriately treated by alkaline precipitation and solvent extraction techniques using sodium hydroxide and (di-2-ethylhexyl) phosphoric acid (D2EHPA) respectively, to obtain pure manganese solution. The purified solution was further beneficiated to obtain manganese sulphate monohydrate (MnSO4.H2O, melting point?=?692.4 °C: 47-304-7403) of high industrial value. The unleached residue (~?19.8%) analyzed by XRD consisted of silicileous impurities (SiO2) which could serve as an important by-product for some defined industries.  相似文献   
75.
Polyaniline (PANI) was doped with five novel dopants, 3‐pentadecylphenylphosphoric acid (PDPPA), pentadecylphenyl(bis)phosphoric acid [PDP(bis)PA], monocardanylphosphoric acid (MCPA), dicardanylphosphoric acid (DCPA), and phosphorylated cashew nut shell liquid prepolymer (PCNSL) and the doping behavior was studied. All dopants were synthesized from inexpensive naturally existing monomers [obtained from cashew nut shell liquid (CNSL)] having a long hydrophobic hydrocarbon side chain in the meta position of the aromatic ring. These dopants can act as plasticizing cum protonating agents for PANI so that free‐standing films of PANI could be prepared by both thermal processing and solution processing techniques. Protonation was performed either by mechanical mixing of emeraldine base and the dopant or by an in situ doping emulsion polymerization route using xylene or chloroform as the solvent. Further, conductive flexible blends of the protonated PANI with poly(vinyl chloride) (PVC) were also prepared and studied for their conductivity and related properties. The PANI–PDPPA complex obtained by the in situ doping emulsion polymerization route exhibited an exceptionally high degree of crystalline order and orientation. A maximum conductivity value of 1.8 S cm?1 was obtained for a PANI–PDPPA film hot‐pressed at 120°C. On the other hand, dopants based on cardanol having an unsaturated side chain gave only lower values. This was understood to be due the capability of the saturated analog to contribute to the ordered arrangement of PANI, thus improving the crystallinity. The conductivity values further decreased when bulky/oligomeric dopants such as PCNSL were used. The thermoplastic blends with PVC exhibited an exceptionally low‐level percolation threshold because of the plasticizing nature of the dopants. The doped polymers and blends were characterized by FTIR and UV‐visible spectroscopic methods, four‐probe conductivity measurements, XRD, SEM, TGA, and DSC. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1354–1367, 2001  相似文献   
76.
NR(natural rubber)based and its blend with BR(polybutadiene rubber)and NBR(nitrile rubber)composites were synthesized using reinforcing filler and other relevan...  相似文献   
77.
Cobalt oxide nanoparticles@nitrogen-doped reduced graphene oxide (Co3O4@N-rGO) composite and nitrogen-doped graphene dots (N-GDs) were synthesized by a one-pot simple hydrothermal method. The average sizes of the synthesized bare cobalt oxide nanoparticles (Co3O4 NPs) and Co3O4 NPs in the Co3O4@N-rGO composite were around 22 and 24 nm, respectively with an interlayer distance of 0.21 nm, as calculated using the XRD patterns. The Co3O4@N-rGO electrode exhibits superior capacitive performance with a high capability of about 450 F g?1 at a current density of 1 A g?1 and has excellent cyclic stability, even after 1000 cycles of GCD at a current density of 4 A g?1. The obtained N-GDs exhibited high sensitivity and selectivity towards Fe2+ and Fe3+, the limit of detection was as low as 1.1 and 1.0 μM, respectively, representing high sensitivity to Fe2+ and Fe3+. Besides, the N-GDs was applied for bio-imaging. We found that N-GDs were suitable candidates for differential staining applications in yeast cells with good cell permeability and localization with negligible cytotoxicity. Hence, N-GDs may find dual utility as probes for the detection of cellular pools of metal ions (Fe3+/Fe2+) and also for early detection of opportunistic yeast infections in biological samples.  相似文献   
78.
A new emulsion liquid membrane was prepared for dysprosium (Dy) extraction from aqueous solution using multi‐walled carbon nanotubes (MWCNTs). The influence of MWCNT concentration, carrier and surfactant concentration, stirring speed, feed‐phase pH, and internal phase concentration and their interactive effects were studied. A regression model for Dy extraction was developed and the parameters were optimized by response surface methodology. The extent of extraction increases with higher MWCNT concentration up to a certain level. The Dy extraction through the liquid membrane containing MWCNT improves with time. Moreover, the overall mass transfer coefficient was enhanced in the presence of MWCNT due to the formation of a more stable emulsion and liquid membrane.  相似文献   
79.
80.
Hitam  C. N. C.  Jalil  A. A.  Raji  Y. O. 《Topics in Catalysis》2020,63(11-14):1169-1181
Topics in Catalysis - Novel fibrous silica zinc (FSZnIS) catalyst was synthesized by in-situ hydrothermal-microwave method and the catalyst was analyzed by X-ray Diffraction (XRD), N2...  相似文献   
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