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71.
Single bit failure is the most common failure mode in static random access memory. Although a failing cell can be easily localized with bitmap data, the exact defect location within the failing cell cannot be found immediately, especially when a defect is related to contact. In this paper, a technique of contact-level passive voltage contrast has been proposed to detect such defects for a single bit failure. After an open contact was identified, subsequent transmission electron microscope analysis was performed and it was found that the root cause for the open contact was poly residue.  相似文献   
72.
A distinct feature of process industries such as food, chemical and consumer packaged goods is the blending of intermediates into finished goods. In the context of such manufacturing systems the levels of different inputs that can be blended to process a final good define the range of flexibility. Likewise, the cost for using (blending) different inputs defines the mobility element of flexibility. In this paper, we investigate capacity investment and the value of flexibility in the presence of such product blending constraints. We are motivated by recent case studies of food manufacturers, in particular, those manufacturers that seek to increase flexibility via blending of intermediates. We analyse stochastic programs under demand uncertainty of such manufacturing systems. We provide analytical insights into trade-offs when range and mobility are interdependent. Our analytical work gives structural insights into subtle complementarity and substitution effects between dedicated and shared resources in the presence of blending. We analytically show that there is a degradation in the cost performance of such systems with an increase in correlation. We characterise the optimal blending fraction that balances the benefits of higher range with higher costs (lower mobility). Our numerical work shows that a moderate level of blending can significantly improve flexibility and that well-known guidelines for designing limited flexibility change in the presence of blending. For example, blending, even if optimally designed, weakens the appeal of chaining configurations. Overall our work guides resource configuration in industries where product blending is an integral part of the production process.  相似文献   
73.
In thermoplastic pipe extrusion, the extrudate emerging from the die is typically sized and cooled from outside in a quench tank. This process causes quick solidification of the external layer, while the inner mass of molten material cools only gradually. The slow cooling and crystallization, and the associated shrinkage of this material, can lead to build-up of severe stresses in the final part that can affect the long term service performance. In this paper, a simple theoretical analysis of this process of residual stress build-up is presented. The pipe undergoing quenching is modeled as an annular cylinder of molten polymer being cooled at a controlled rate from outside. The overall stresses are derived numerically by adding up the stress contributions due to incremental advance of the solidification boundary. The results of the analysis are found to be in qualitative accord with the experimentally measured stress profiles in thermoplastic pipe.  相似文献   
74.
特殊的高纯度脂肪酸酯及其混合物可用于制备较低气味,无VOC,可再生的成膜助剂.这种成膜助剂可以提高极低VOC涂料中乳液的效果.实验证明:与非再生成膜助剂相比,该新产品不仅能降低配方的综合成本,还能明显提高性能.  相似文献   
75.
Eichhornia spp. biomass was collected from Chandola Lake, Ahmedabad, Gujarat, India. Point of zero charge of the biomass was pH 7.3. Flask study showed pH 5 and 2–3 h contact time as optimum conditions for copper sorption with 67.25% copper removal. At the end of 24 h of contact time, copper removal reached to 85.0%, from 100 ppm copper containing solution. Copper loading capacity of the biomass ranged between 9.9 and 28.5 mg g?1 of biomass. To understand the interaction among pH, temperature, presence of nickel and zinc in the system, 24 factorial experiment was performed. Under the experimental conditions pH and interactions between pH–nickel, temperature–pH and temperature–pH–nickel–zinc were found to be significant with 60–74.7% copper removal. Langmuir isotherm was better fit as compared to Freundlich isotherm and pseudo-second order equation gave R2 of 0.999 for biosorption kinetic of Eichhornia biomass. Reactor study showed 90% overall copper removal from 24 L of copper containing waste studied and sulphate-reducing bacteria played a significant role. SEMquant element analysis showed increase from 41.66% to 53.93%, 1.02–19.73% and 0.0–12.39% of chloride, aluminium and copper respectively in the loaded biomass as compare to unexposed biomass.  相似文献   
76.
An efficient and simple method is reported for the cyanation on arylboronic acid using various simple/indole thiocyanates using a new IL-PdCl4 catalyst. The cascade process involves a coupling reaction without any additive to give a wide range of cyanide derivatives. Cyanation on various arylboronic acids underwent smoothly affording the corresponding arylnitriles in good to high yields.  相似文献   
77.
78.
According to the Earth Observatory dust outbreaks are considered as natural hazards, which affect the ecosystems and human life. The main objective of this study is to assess and monitor the movement of aerosols and pollutants from local or other sources, both natural and anthropogenic, using a combination of ground-based monitoring and satellite data. The turbid and polluted atmosphere in the densely-populated area of Hyderabad, India is further degradated from dust outbreaks originated from Thar desert. A dust event occurred during 10th to 11th April 2006 in the northwest region of India; its plume substantially spreaded across the downwind direction affecting the study region. Using both irradiance measurements and satellite data this dust event is investigated. The analysis shows a significant change in Aerosol Optical Depth (AOD), Aerosol Index (AI) and aerosol-particle size during the dust event. The Aerosol Optical Depth in the dusty day is about 0.2 higher than the previous non-dusty days, while the Angstr?m exponent rapidly decreases when the dust plume affected the study area. The surface PM concentrations show enhanced values during the dusty day directly influenced by the dust deposition. There is also a remarkable decrease in ground-reaching global radiation, UV erythemal (UV(ery)) and other irradiance components. The analysis suggested that the use of the diffuse-to-direct-beam ratio is the most appropriate parameter for the dust monitoring since its values at the longer wavelengths are not affected by the solar zenith angle.  相似文献   
79.
This paper discusses a novel plasma-spraying process for depositing dense LaCrO3-based interconnection for solid oxide fuel cells (SOFCs). Calcium aluminate was mixed with LaCrO3 in a slurry containing PVA binder and spray dried to form free-flowing agglomerates. These free-flowing agglomerates were plasma sprayed onto a porous substrate of doped LaMnO3 and then heat-treated to form a gas-tight and electrically conducting interconnection. Samples of the plasma-sprayed interconnection were characterized for morphology, phase constituents, and coefficient of thermal expansion, as well as electrical resistivity and oxygen nonstoichiometry at 1000°C in the P O2 range from 1 to} 1× 10-16 atm. The calcium aluminate additive was found to facilitate densification of the interconnection, most likely through the formation of low-temperature melting phase(s) in the system Ca–Cr–Al–O. A SOFC with such a plasma-sprayed interconnection was fabricated and electrically tested. This cell exhibited good electrical performance, and the interconnection was stable under fuel cell operation conditions.  相似文献   
80.
A nano-composite was formed by incorporating nano-ZnO in a specially developed alkyd-based waterborne coating to different loading levels. The nano-ZnO based composite coatings were applied on mild steel substrate by dipping. The coated panels were subjected to various test environments like salt-spray, humidity, UV and mechanical tests like scratch and abrasion. The improvement in electrochemical performance and mechanical properties of the composite coatings were evaluated using various analytical techniques. FTIR technique was used to investigate the interaction between nano-ZnO particles and the polymer functionalities. Differential scanning calorimetry (DSC) was done to study the curing behavior of nano-composite coatings. SEM and AFM were used to investigate dispersion of nano-ZnO particles and the changes in the surface behavior of the coatings before and after exposure to the test environment. The result showed that, with increase in the concentration of nano-ZnO there was an improvement in the corrosion resistance, UV resistance and mechanical properties of the coatings indicating the positive effect of addition of nano-ZnO particles in the coatings.  相似文献   
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