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11.
BACKGROUND: Bioethanol is mostly produced from starchy parts of the corn grain kernel leaving significant amounts of valuable by‐products such as dried distillers' grains with solubles (DDGS) which can be used as a substitute for traditional feedstuff. The suitability of six maize hybrids from Serbia was investigated for bioethanol and DDGS production. The correlation between physical and chemical characteristics of the grain, bioethanol yield and quality of the corresponding DDGS was assessed. RESULTS: All hybrids had very different chemical composition and physical characteristics which could allow various applications. The highest bioethanol yield (94.5% of theoretical) and volumetric productivity (2.01 g l?1 h?1) were obtained with hybrid ZP 434 and the lowest with ZP 611k. Regarding chemical composition, all DDGS samples manifested good properties as feed components. Their protein content was higher compared to the kernel. In addition, the samples showed high digestibility and high mineral content, especially of calcium and phosphorus. CONCLUSION: A hybrid ZP 434 was selected as the most promising bioethanol producer. This property is attributed to the highest level of soft endosperm which is more susceptible to starch‐hydrolysing enzymes. A high yield potential per hectare makes it the best candidate for commercial bioethanol production. © 2012 Society of Chemical Industry  相似文献   
12.
Towards action refinement for true concurrent real time   总被引:2,自引:0,他引:2  
Action refinement is an essential operation in the design of concurrent systems, real-time or not. In this paper we develop a theory of action refinement in a real-time non-interleaving causality based setting, a timed extension of bundle event structures that allows for urgent interactions to model timeout. The syntactic action refinement operation is presented in a timed process algebra as incorporated in the internationally standardised specification language LOTOS. We show that the behaviour of the refined system can be inferred compositionally from the behaviour of the original system and from the behaviour of the processes substituted for actions with explicitly represented start points, that the timed versions of a linear-time equivalence, termed pomset trace equivalence, and a branching-time equivalence, termed history preserving bisimulation equivalence, are both congruences under the refinement, and that the syntactic and semantic action refinements developed coincide under these equivalence relations with respect to a metric denotational semantics. Therefore, our refinement operations behave well. They meet the commonly expected properties.Received: 9 January 2003  相似文献   
13.
Carbon monoxide (CO) can be used to treat fresh meat and fish in order to retain its ‘fresh’ red colour appearance for a longer period of time. In fact, upon aging, myoglobin is oxidized to met-myoglobin with the concomitant blue-shift and broadening of the Soret maximum, which brings about a change in the colour of the fish, revealing that it is no longer fresh. The use of carbon monoxide, which reacts with the oxy-myoglobin to form a fairly stable cherry red carboxy-myoglobin complex may mask spoilage, because the CO-complex can be stable beyond the microbiological shelf life of the meat. The presence of CO in tuna fish has been investigated by optical spectroscopy as the formation of the CO adduct can be easily detected by the combined analysis of electronic absorption spectra in their normal and second derivative modes, monitoring the intense Soret band at 420 nm. The presence of met- and oxy-myoglobin can obscure the presence of small amounts of the CO adduct; however, it can be revealed by chemically reducing the met- and oxy-forms to the deoxy-form in an anaerobic environment. This spectroscopic method provides a qualitatively rapid laboratory screening procedure for food control to unmask the presence of CO in frozen or fresh fish.  相似文献   
14.
A tapered cantilevered optical fiber probe is introduced for fluorescence correlation spectroscopy (FCS). The probe has an aperture that is coated with metal and its dimension can be very well defined. Its design is based on cantilevered near-field optical fiber probes that allow for on-line atomic force feedback. This permits unprecedented stability in FCS measurements. Even such probes that have large diameters are below the cutoff wavelength of light propagation in optical fibers. Such large diameter probes produce bright spots of light that are highly diffracting. Therefore, only the fluence of light very close to the surface of the glass probe aperture is sufficient to exhibit a high probability of fluorescence excitation. From the results presented in this paper the z extent of such probes seems comparable to what can be obtained from prism-based evanescent wave methods, but with much more flexibility and including force sensing capability. In agreement with theoretical results on prism evanescent field-based excitation, it is shown that even with large xy dimensions for the fiber probes in this paper, fluorescence correlation spectra from 100 nM fluorophore concentrations can be recorded. This is 10 times larger than the concentrations generally required for conventional confocal FCS. The results suggest that such an approach has considerable potential for applications of FCS in membrane, near-membrane, solution, and even within-cell environments. The latter is achieved through atomic force feedback controlled penetration of tapered cantilevered metal-coated glass fibers into cells, and this is also reported in this paper.  相似文献   
15.
Temperature- and pH-sensitive hydrogels based on N-isopropylacrylamide (NiPAAm) and itaconic acid (IA) were applied for immobilization of lipase from Candida rugosa (CRL). The hydrogels were synthesized by free radical crosslinking copolymerization in the presence of lipase. Characterization of samples by swelling studies, at pH 2.20 and 6.80 at a temperature of 37 °C, scanning electron microscopy (SEM) and Fourier transform infrared analysis (FT-IR) confirmed that the degree of crosslinking, the non-ionic/ionic (NiPAAm/IA) ratio and the enzyme content had impacts on the hydrogel structure, mechanical properties, morphology and swelling kinetics. All hydrogels demonstrated protein loading efficiencies as high as 95 wt.%. A specific activity of the immobilized lipase of around 38 IU/g was attained for an enzyme loading of 20.0 wt.%. As a result, improved pH and temperature optima values were obtained for the immobilized systems in relation to those for the free lipase.  相似文献   
16.
The paper summarizes the findings of investigation of the influence of physicochemical and physical-mechanical properties of synthetic diamond grits on the drilling tool performance. Wear resistance of drilling tools is demonstrated to increase when they are fitted with synthetic diamond grits that are highly uniform in strength. The use of diamond grits with a better developed surface is found to provide a stronger grit retention in the bond and reduced drilling tool wear.  相似文献   
17.
A study involving the immediate loading of Br?nemark implants in the edentulous mandibles of 10 patients is reported. The design involved the immediate loading of four widely distributed implants with a transitional fixed implant-supported prosthesis at first-stage surgery, avoiding the need for a removable prosthesis. A sufficient number of additional implants are allowed to heal in the conventional manner to provide sufficient support for a definitive fixed prosthesis even if all of the immediately loaded implants fail. Preliminary results have been favorable, with all patients functioning with a fixed implant prosthesis from the day of first-stage surgery.  相似文献   
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