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71.
72.
The pyrolysis of poly-(methyl methacrylate) (PMMA) has been studied in a pyrolysis plant provided with a conical spouted bed reactor. This reactor is an interesting technology for the pyrolysis of waste plastics due to its excellent hydrodynamic behaviour and its high heat transfer and versatility. A previous kinetic study was carried out in thermobalance, in which the degradation of this polymer was observed to begin at low temperatures, 553 K. Consequently, the activation energy is low compared to other plastics. The influence of temperature on pyrolysis product distribution in the conical spouted bed reactor has been studied in the 673–823 K range. The products obtained at low temperatures are mainly the monomers of the polymer used for the study methyl methacrylate (MMA) and ethyl acrylate (EA). When the pyrolysis temperature is increased, the yield of monomers is lower due to the higher severity of secondary reactions, and there is a significant increase in the yield of gases. The maximum monomer recovery has been obtained at 673 K, with the yields of MMA and EA being 86.5% and 6.2%, respectively.  相似文献   
73.
We introduce a lattice independent component analysis (LICA) unsupervised scheme to functional magnetic resonance imaging (fMRI) data analysis. LICA is a non-linear alternative to independent component analysis (ICA), such that ICA’s statistical independent sources correspond to LICA’s lattice independent sources. In this paper, LICA uses an incremental lattice source induction algorithm (ILSIA) to induce the lattice independent sources from the input dataset. The ILSIA computes a set of Strongly Lattice Independent vectors using properties of lattice associative memories regarding Lattice Independence and Chebyshev best approximation. The lattice independent sources constitute a set of Affine Independent vectors that define a simplex covering the input data. LICA carries out data linear unmixing based on the lattice independent sources basis. Therefore, LICA is a hybrid combination of a non-linear lattice based component and a linear unmixing component. The principal advantage over ICA is that LICA does not impose any probabilistic model assumptions on the data sources. We compare LICA with ICA in two case studies. Firstly, including simulated fMRI data, LICA discovers the spatial location of meaningful sources with less ambiguity than ICA. Secondly, including real data from an auditory stimulation experiment, LICA improves over some state of the art ICA variants discovering the activation patterns detected by Statistical Parametric Mapping (SPM) on the same data.  相似文献   
74.
本文综述了以介绍海岸规划、高铁城市、城区更新和战略发展为主要内容的"巴塞罗那模式"的规划策略,并介绍了其对巴塞罗那城市发展的重要引导作用,以期为其他历史性城市的复兴提供参考。  相似文献   
75.
Ropy Pediococcus damnosus (strain 2.6) was used for production of exopolysaccharide (EPS) in a semidefined medium. From a kinetic point of view, an experiment conducted in SMD medium containing 30 g l(-1) glucose and 5 g l(-1) Bacto casamino acids (Difco Laboratories, Detroit, MI), without pH control, showed that EPS production took place mainly during the growth phase. The viscosity of the cultures developed in parallel to the EPS synthesis until 94 h of incubation; after 200 h of fermentation, viscosity decreased. The effect of glucose, Bacto casamino acid concentrations and temperature on growth and EPS production was determined by using a full factorial design. Within the domain of experimental conditions considered, the concentration of glucose and Bacto casamino acids has a significant effect on the production of exopolysaccharide. The incubation at 12 degrees C produced a prolonged lag phase and due to the lower growth yield, higher specific EPS production was found at this temperature. At 25 degrees C the EPS production was mainly enhanced by the increase in glucose concentration. The increase in nitrogen concentration from 5 to 15 g l(-1) did not yield greater EPS production. However, at 12 degrees C optimal EPS production was obtained when both higher glucose and nitrogen concentrations were used.  相似文献   
76.
Infection systems where traits of the host, such as acquired immunity, interact with the infection process can show complex dynamic behaviour with counter-intuitive results. In this study, we consider the traits ‘immune status’ and ‘exposure history’, and our aim is to assess the influence of acquired individual heterogeneity in these traits. We have built an individual-based model of Eimeria acervulina infections, a protozoan parasite with an environmental stage that causes coccidiosis in chickens. With the model, we simulate outbreaks of the disease under varying initial contaminations. Heterogeneity in the traits arises stochastically through differences in the dose and frequency of parasites that individuals pick up from the environment. We find that the relationship between the initial contamination and the severity of an outbreak has a non-monotonous ‘wave-like’ pattern. This pattern can be explained by an increased heterogeneity in the host population caused by the infection process at the most severe outbreaks. We conclude that when dealing with these types of infection systems, models that are used to develop or evaluate control measures cannot neglect acquired heterogeneity in the host population traits that interact with the infection process.  相似文献   
77.
With the growing acceptance of the borderline personality disorder diagnosis for adolescents has come a need for specialized treatments for this challenging population. Further, because of the prominence of the family system during early and later adolescence, family treatments are particularly needed. The purpose of this article is to present the integrative borderline adolescent family therapy (I-BAFT) model that emerged from a National Institute on Drug Abuse-funded (Stage 1) treatment development and enhancement effort. I-BAFT integrates (a) key interventions from the family treatment of adolescent drug abuse (D. A. Santisteban et al., 2003; J. Szapocznik & W. Kurtines, 1989), (b) skills training shown effective with adults with borderline personality disorder (M. Linehan, 1993a) and adapted for adolescents, and (c) individual treatment interventions that promote motivation for treatment and enhance the integration of the 3 treatment components. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
78.
On the basis of an analysis of results presented in the literature, the currently existing knowledge about relationships between the microstructural and physical properties of hard coatings is discussed. Particular emphasis is placed on the role of microstructural features, such as grain boundaries, nonequilibrium structures, impurities, and texture, in controlling the film hardness. On the basis of an analysis of results presented in the literature, the currently existing knowledge of electrically conductive adhesives (ECAs) is discussed. Particular focus is placed on the results obtained with ECAs that contain carbon nanotubes (CNTs) as conductive fillers. The review is divided in curable ECAs based on epoxy resins, and noncurable conductive hot melts and pressure‐sensitive adhesives based on thermoplastic polymers. More literature results were found for epoxy/conductive filler ECAs than for other adhesives. Confirming the assessments made in a book by Li et al., which refers to nanotechnologies in ECAs, we found that only a reduced number of articles allude to polymer/CNT ECAs. Our analysis of the results includes a study of the balance between the viscosity, immediate adhesion, solidification process, electrical conductivity, and mechanical properties of the adhesives. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
79.
Water resource management is often a controversial issue in semiarid regions. Most water resources experts admit that water conflicts are not caused by the physical water scarcity but they are mainly due to inadequate water management. The virtual water concept (the volume of water used in the production of a commodity, good or service) together with the water footprint (indicator of water consumption that looks at both direct and indirect water use of a consumer or producer), links a large range of sectors and issues, thus providing a potentially appropriate framework to support more optimal water management practices by informing production and trade decisions. This paper provides an analysis of these two concepts within the context of the Mancha Occidental region, Spain, exploring the hydrological and economic aspects of agricultural production. In doing so, this work not only distinguishes between green and blue water but also between surface and groundwater. We conclude by discussing the practical implications of the results, as well as their potential limitations from the policy standpoint.  相似文献   
80.
The psychology of tourism is a new, multidisciplinary research field. However, no systematic analyses of the scientific production in this field have been carried out to date. This study presents a bibliometric analysis of the area of psychology of tourism between 1990 and 2005. The evolution of scientific production during this period, Price’s, Lotka’s and Bradford’s laws and citation patterns were studied. The results show a significant growth in the literature on the subject, as well as an increase in coauthorship and institutional collaboration. Bibliometric laws and empiric regularities observed in other disciplines are also present in this new research field.  相似文献   
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