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81.
La0.8Sr0.2Ga0.8Mg0.115Co0.085O3−δ (LSGMC) powders were prepared by polymeric precursor synthesis, using either polyvinyl alcohol (PVA) or citric acid (CA) as complexing agents. The powders were synthesized using different ratios between the complexing agent and the cations dissolved in solution. The obtained polymer gel precursors were dried and calcined at temperatures between 1000° and 1450°C. Single-phase LSGMC powders were obtained at a firing temperature of 1450°C, using PVA and a molar ratio between the hydroxylic groups and the total cations of 3:1. Phase-pure LSGMC powders were used to sinter (1490°C, 2 h) thick pellets. The functional properties of LSGMC pellets were assessed by electrochemical impedance spectroscopy. The electrical conductivity values and the apparent activation energies in different transport regimes were in agreement with literature data. The same LSGMC powders were deposited by electrophoretic deposition (EPD) on a green membrane containing lanthanum-doped ceria (La0.4Ce0.6O2− x , LDC), a binder, and carbon powders. The LSGMC/LDC bi-layer obtained by EPD was cofired at 1490°C for 2 h. A dense and crack-free 8-μm-thick LSGMC film supported on a porous skeleton of LDC was obtained. The combined use of proper powder synthesis and film processing routes has thus proven to be a viable way for manufacturing anode-supported LSGMC films.  相似文献   
82.
The surface composition of cemented tungsten carbide (WC-5.8 wt% Co) was studied by X-ray photoelectron spectroscopy (XPS), during the early stages of diamond-film deposition, by hot-filament chemical vapor deposition (HFCVD). The nucleated diamond films were analyzed by scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and automatic image analysis (AIA). The evolution of the surface composition of cemented tungsten carbide during the early stages of diamond-film deposition was strongly dependent on the substrate temperature. At relatively low temperature (750°C), cobalt-rich particles started to segregate at the substrate surface after a few minutes of diamond deposition. The conspicuous segregation of the binder partly inhibited the formation of stable diamond nuclei, through intense carbon dissolution or carbon segregation at the binder surface, but did not affect nucleic growth. At higher temperatures (940°C), no cobalt-rich particles formed at the substrate surface, even after 2 h of deposition. However, XPS results demonstrated the presence of cobalt in a surface layer, although in a lower amount than at 750°C. Nevertheless, the nucleation density of diamond at 940°C was much lower than at 750°C. Gaps between WC grains formed within 10 mins. Therefore, intergranular cobalt was removed at 940°C, a finding attributed to the etching performed by monohydrogen, rather than to binder evaporation. The time evolution of the substrate area fraction covered by diamond islands, S ( t ), was well described by Avrami kinetics for two-dimensional phase transformations, suggesting that diamond formation took place via a heterogeneous nucleation process. The S ( t ) functions exhibited a similar trend at 750° and 940°C, because the higher growth rate of diamond crystallites at higher temperature counteracted the slower nucleation rate at the higher temperature.  相似文献   
83.
Ohne ZusammenfassungMitteilung aus dem Nahrungsmitteluntersuchungsamt (Vorsteher: Privatdozent Dr. J. Tillmans) des städt. hygien. Universitätsinstituts in Frankfurt a. M. (Direktor: Prof. Dr. M. Neisser).  相似文献   
84.
Therapeutic change involves integration of emotion schemas that have been dissociated. Two types of avoidant dissociation are distinguished: primary dissociation dominated by fragmentary emotional memories; and secondary dissociation involving initial encoding of more organized memories whose meaning is avoided. Reconstruction of dissociated emotion schemas occurs through the referential process which includes three basic components: arousal of the subsymbolic affective core of a dissociated schema in the treatment relationship; connections of subsymbolic processes to symbolic representations in narratives and interactions in the session; and reflection leading to reorganization of the schema. The role of enactive perception and embodied communication as underlying intersubjectivity in the referential process is reviewed. Variations in states of awareness associated with each phase of the process, in both analyst and patient, and their effects on therapeutic change are examined. Current work in cognitive science and affective neuroscience supporting this process model is reviewed. This formulation is largely compatible with Freud's early theory of recollection and “associative working-over” with new emphasis on subjective state and the relational context. Studies of the referential process provide a potential interface between investigations of psychotherapy process and basic cognitive science and neuroscience research. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
85.
We present a field study with a game for children called ‘Tap the little hedgehog’, which is played on the TagTiles console, a tangible electronic interface. The game was developed to train and assess cognitive skills and includes tasks which, in isolation, exhibit a high correlation with a number of subtests from the Wechsler Intelligence Scale for Children (WISC-III-NL). The tasks address a range of nonverbal skills by requiring children to perform different operations on abstract patterns such as copying, reproducing sequences from memory and mirroring patterns. In the current study, we tested whether these tasks kept their ability to address these skills if included in a gaming context, whether children are able to play the game independently and whether they are motivated to play the game. The results of the study support the hypothesis that nonverbal IQ-scores, as measured by the Wechsler Intelligence Scale for Children, can improve by training with a game. Hence, games like ‘Tap the little hedgehog’ can be used to train specific skills and serve as a screening tool for these skills. The results also confirm that children can play the game independently and that they enjoy it. We further found that children quickly learn how to play the game and use the interface.  相似文献   
86.
Detonation nanodiamond (ND) particles were dispersed on silicon nitride (SiNx) coated sc-Si substrates by spin-coating technique. Their surface density was in the 1010–1011 cm?2 range. Thermal stability and surface modifications of ND particles were studied by combined use of X-ray Photoelectron Spectroscopy (XPS) and Field Emission Gun Scanning Electron Microscopy (FEG SEM). Different oxygen-containing functional groups could be identified by XPS and their evolution versus UHV annealing temperature (400–1085 °C) could be monitored in situ. The increase of annealing temperature led to a decrease of oxygen bound to carbon. In particular, functional groups where carbon was bound to oxygen via one σ bond (C–OH, C–O–C) started decomposing first. At 970 °C carbon–oxygen components decreased further. However, the sp2/sp3 carbon ratio did not increase, thus confirming that the graphitization of ND requires higher temperatures. XPS analyses also revealed that no interaction of ND particles with the silicon nitride substrate occurred at temperatures up to about 1000 °C. However, at 1050 °C silicon nitride coated substrates started showing patch-like damaged areas attributable to interaction of silicon nitride with the underlying substrate. Nevertheless ND particles were preserved in undamaged areas, with surface densities exceeding 1010 cm?2. These nanoparticles acted as sp3-carbon seeds in a subsequent 15 min Chemical Vapour Deposition run that allowed growing a 60–80 nm diamond film. Our previous study on Si(100) showed that detonation ND particles reacted with silicon between 800 and 900 °C and, as a consequence, no diamond film could be grown after Chemical Vapour Deposition (CVD). These findings demonstrated that the use of a thin silicon nitride buffer layer is preferable insofar as the growth of thin diamond films on silicon devices via nanoseeding is concerned.  相似文献   
87.
Agent-Based Modeling and Simulation (ABMS) has arisen as new approach to effectively support domain experts to cope with the growing complexity of the problems which they have to face and solve. To date, few methodologies are available which can be exploited by domain experts with limited programming expertise to model and subsequently analyze complex systems typical of their application domains. In this paper the easyABMS methodology is proposed to overcome the lack of integrated methodologies able to seamlessly guide domain experts from the analysis of the system under consideration to its modeling and analysis of simulation results. The effectiveness of easyABMS is also experimented through a case study in the logistics domain which concerns the analysis of different policies for managing vehicles used for stacking and moving containers in a transhipment terminal.  相似文献   
88.
Natural antimicrobials are being more and more considered as alternative approach for controlling growth of microorganisms in food. The objective of this study was to evaluate the pomegranate extract’s (PE) potential to be used as a natural preservative in ready to eat meats. Listeria monocytogenes was the main target. In a preliminary assessment with the disk diffusion method PE showed inhibitory effect against all five tested species, in the following order of increasing sensitivity: L. monocytogenes, Bacillus subtilis, Bacillus cereus, Escherichia coli and Staphylococcus aureus.No viable cells of L. monocytogenes were detected after incubation in BHI broth in presence of 7.5% v/v of the liquid PE (or 24.7 mg dry PE/ml). This concentration was considered as the Minimal Bactericidal Concentration (MBC) of the tested PE. Two pure components commonly found in PE, namely gallic and ellagic acids were also tested in BHI broth, however they did not show considerable inhibition of L. monocytogenes. PE in a concentration equal to the measured MBC was tested against L. monocytogenes in meat paté at different temperatures. At 4 °C during 46 days the extract inhibited the growth in meat paté by 4.1 log CFU/g compared to the control, which had reached log 9.2 CFU/g already on the 18th day. Inhibition was less pronounced at higher temperatures. The results indicate that the PE has a potential to be used as a natural preservative in meat products.  相似文献   
89.
Surface modification of sulfur by vacuum plasma polymerization with acetylene was applied in order to modify its surface properties without losing reactivity for vulcanization. A nm‐thin layer of crosslinked polyacetylene was deposited on the surface of the sulfur powder. Its surface energy was decreased as monitored by wetting in liquids of various polarities. A delay in the onset of weight loss by sublimation in thermal gravimetric analysis was shown by the plasma‐modified sulfur. Scanning electron microscopy showed a core/shell structure of the coated sulfur. In 50:50 blends of styrene‐butadiene rubber and ethylene‐propylene‐diene rubber, the encapsulated sulfur samples resulted in pronounced improvements in the mechanical properties relative to the use of unmodified sulfur.

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90.
Early diagnosis of cancer is of pivotal importance to reduce disease-related mortality. There is great need for non-invasive screening methods, yet current screening protocols have limited sensitivity and specificity. The use of serum biomarkers to discriminate cancer patients from healthy persons might be a tool to improve screening programs. Mass spectrometry based proteomics is widely applied as a technology for mapping and identifying peptides and proteins in body fluids. One commonly used approach in proteomics is peptide and protein profiling. Here, we present an overview of profiling methods that have the potential for implementation in a clinical setting and in national screening programs.  相似文献   
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