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71.
The Fusion Advanced Study Torus (FAST) has been proposed as a possible European satellite, in view of ITER and DEMO, in order to: (a) explore plasma wall interaction in reactor relevant conditions, (b) test tools and scenarios for safe and reliable tokamak operation up to the border of stability, and (c) address fusion plasmas with a significant population of fast particles. A new FAST scenario has been designed focusing on low-q operation, at plasma current IP = 10 MA, toroidal field BT = 8.5 T, with a q95  2.3 that would correspond to IP  20 MA in ITER. The flat-top of the discharge can last a couple of seconds (i.e. half the diffusive resistive time and twice the energy confinement time), and is limited by the heating of the toroidal field coils. A preliminary evaluation of the end-of-pulse temperatures and of the electromagnetic forces acting on the central solenoid pack and poloidal field coils has been performed. Moreover, a VDE plasma disruption has been simulated and the maximum total vertical force applied on the vacuum vessel has been estimated.  相似文献   
72.
A lignin fraction (LF) was extracted from the sea balls of Posidonia oceanica (egagropili) and extensively dialyzed and characterized by FT-IR and NMR analyses. LF resulted water soluble and exhibited a brownish-to-black color with the highest absorbance in the range of 250–400 nm, attributed to the chromophore functional groups present in the phenylpropane-based polymer. LF high-performance size exclusion chromatography analysis showed a highly represented (98.77%) species of 34.75 kDa molecular weight with a polydispersity index of 1.10 and an intrinsic viscosity of 0.15. Quantitative analysis of carbohydrates indicated that they represented 28.3% of the dry weight of the untreated egagropili fibers and 72.5% of that of LF. In particular, eight different monosaccharides were detected (fucose, arabinose, rhamnose, galactose, glucose, xylose, glucosamine and glucuronic acid), glucuronic acid (46.6%) and rhamnose (29.6%) being the most present monosaccharides in the LF. Almost all the phenol content of LF (113.85 ± 5.87 mg gallic acid eq/g of extract) was water soluble, whereas around 22% of it consisted of flavonoids and only 10% of the flavonoids consisted of anthocyanins. Therefore, LF isolated from egagropili lignocellulosic material could be defined as a water-soluble lignin/carbohydrate complex (LCC) formed by a phenol polymeric chain covalently bound to hemicellulose fragments. LCC exhibited a remarkable antioxidant activity that remained quite stable during 6 months and could be easily incorporated into a protein-based film and released from the latter overtime. These findings suggest egagropili LCC as a suitable candidate as an antioxidant additive for the reinforcement of packaging of foods with high susceptibility to be deteriorated in aerobic conditions.  相似文献   
73.
A typical hazard perception test presents participants with a single-screen view of the road ahead. This study assessed how increasing this field of view would affect hazard perception abilities. Drivers were shown video clips of driving situations containing at least one hazard either on a single screen, or with the addition of side views on two separate but adjacent screens that extended the perceived worldview to approximately 180°. Mirror information was also included to allow information from behind the vehicle to be attended. Participants were instructed to press a button as soon as they saw a hazard. Faster response times were found for hazards that appeared in the centre of the central screen, than in the periphery of the central screen, with hazards that first appeared in the lateral screens responded to slowest. Additionally, responses to the hazards were faster and were more likely to occur in the three-, as compared to the single-screen condition. These results suggest that providing participants with a wider field of view, which includes more environmental cues that are related to the relevant hazardous situation increases their ability to detect hazards, and some limited support to that providing them with a wider view increases this ability even when all hazard-relevant information appear only in the central screen. A number of reasons for the three-screen advantage are discussed. This study suggests that even responses to central hazards may be under-estimated in a typical single-screen hazard perception test, and that improvements can be made for new hazard perception tests, by including visual information from the side and from behind the driver. This new methodology not only allows testing hazard perception skills in a potentially more immersive and realistic environment, but also enables to create hazard perception clips that cannot be realised in a typical single-screen test.  相似文献   
74.
We present a library of PVS meta-theories that can be used to verify a class of distributed systems in which agent communication is via message-passing. The theoretical work, as outlined in Chandy et al. (Form Aspect Comput 2011, to appear) consists of iterative schemes for solving systems of linear equations, such as message-passing extensions of the Gauss and Gauss-Seidel methods. We briefly review that work and discuss the challenges in formally verifying it.  相似文献   
75.
This study takes a first step toward understanding the effectiveness of e-court applications in Italy. The proposed research model to assess the success factors for using case management system was tested in two Italian courts. Analysis of survey data from 314 users, using structural equation modeling, reveals the explanatory role of the model and the salient contribution of system and information quality variables on court staff’s performance. Our findings have important implications for theory and practice.  相似文献   
76.
The conformational variation of the viral capsid structure plays an essential role both for the environmental resistance and acid nuclear release during cellular infection. The aim of this study was to evaluate how capsid rearrangement in engineered phages of M13 protects viral DNA and peptide bonds from damage induced by UV-C radiation. From in silico 3D modelling analysis, two M13 engineered phage clones, namely P9b and 12III1, were chosen for (i) chemical features of amino acids sequences, (ii) rearrangements in the secondary structure of their pVIII proteins and (iii) in turn the interactions involved in phage capsid. Then, their resistance to UV-C radiation and hydrogen peroxide (H2O2) was compared to M13 wild-type vector (pC89) without peptide insert. Results showed that both the phage clones acquired an advantage against direct radiation damage, due to a reorganization of interactions in the capsid for an increase of H-bond and steric interactions. However, only P9b had an increase in resistance against H2O2. These results could help to understand the molecular mechanisms involved in the stability of new virus variants, also providing quick and necessary information to develop effective protocols in the virus inactivation for human activities, such as safety foods and animal-derived materials.  相似文献   
77.

New emerging technology 5G will require higher speed, power and capacity in data transmission than previous generation, in order to obtain a complete world-wireless communication without limitation. In this scenario, given that the achievement of 5G technology will lead to a drastic increase of effects of exposure to microwave radiation, a strategy to reduce the effects of exposure to electromagnetic fields is needed. In this regard, given that cellular functions of human beings depend closely on ions flux across cellular membrane, whose mechanism should have its natural resonant frequencies, we can hypothesize to plan new emerging wireless technology 5G at frequencies far from these resonant frequencies in order to minimize the effects of exposure to extremely high frequency electromagnetic fields, inducing a significant decreasing of harmful effects on human health. We have named these frequencies “non-resonant frequencies”.

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78.
Biodegradation kinetics of 4-nitrophenol (4NP) was investigated in a lab-scale sequencing batch reactor fed with the compound as the sole carbon source. The experimental results showed that complete 4NP removal can be easily achieved with acclimatized biomass, even if an inhibition kinetics is observed; furthermore, an improvement in the removal kinetics is obtained if the substrate concentration peak, reached in the reactor at the end of the filling time, is maintained to quite a low value. Both long feed phase and high biomass concentration are effective in reducing the substrate concentration peak and then improving the process efficiency. Kinetic test data are well correlated by the Haldane equation, with a saturation constant Ks and an inhibition constant KI, of 17.6 and 30.7 (mg l(-1) 4NP), respectively, whereas the maximum removal rate was in the range of 3.3-8.4 (mg 4NP mg VSS(-1) d(-1)) depending on the substrate concentration peak reached in the reaction phase.  相似文献   
79.
The study regards 4-nitrophenol removal performed in a lab-scale sequential batch reactor with an integrated aerobic-anoxic cycle. The purpose of the study was to examine the kinetics of 4-nitrophenol biological oxidation and denitrification in order to test the feasibility of the proposed technological solution for xenobiotic removal. The results obtained show that high removal efficiency of 4-nitrophenol is easily achieved when the compound is fed into the reactor as the sole carbon source. Residual concentrations of 4-nitrophenol and nitrous/nitric nitrogen in the effluent lower than 1 mg L(-1) were observed in the range of applied feed concentration (200-320 mg L(-1)). Low concentrations of dissolved oxygen (< or =2 mg L(-1)) in the feed and aerobic phases lead to appreciable simultaneous denitrification. As regards the denitrification process, while no carbon-limiting effects were observed at COD/N ratios > or = 3, a significant decrease in the rate of denitrification is detected for COD/N ratios < or = 2. The denitrification rate obtained in tests with no external carbon addition proved very low and unsuitable for practical application. A model of the denitrification process taking into account both the limiting effect of nitrogen and carbonaceous substrate has been proposed and applied for experimental data correlation.  相似文献   
80.
Polymer derived ceramic (PDCs) aerogels belonging to the Si–O–C–N system are synthesized by crosslinking a preceramic polymer in a diluted solution followed by supercritical or atmospheric drying and pyrolysis in inert (N2) or reactive (NH3/CO2) atmosphere. Accordingly, aerogels with hierarchical porosity ranging from some microns to few nanometers together with high specific surface area in the range 30–400 m2 g?1 have been obtained. Moreover, their surface contains a broad range of moieties (Si–OH, Si–NH, C=O, etc.) that can interact and bind metal ions thanks to electrostatic interactions. This combination of hierarchical porosity, high SSA, and broad range of chemical functionalities makes these PDCs aerogels interesting candidates for water purification. In this work, SiOC and SiCN aerogels have been tested as adsorbents for Cr(III)/(VI) ions from aqueous solutions with promising results for the SiOC aerogel pyrolyzed in N2 and the SiCN treated in NH3. Correlations and similarities among the Cr(VI)/(III) adsorption capacity with the main features of the porous substrates (SSA, N2 TPV, amount of free C, bulk density, isoelectric point, main IR peaks (Si–OH, OH, NH, C=O, C=C, Si–O, C–N, Si–N) have been investigated by applying the Principal Component Analysis (PCA).
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