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81.
Information and communication technologies (ICTs) are having a profound effect in society and organizations. However, the literature on ICT adoption—from selection to implementation—has not been well integrated into leadership theory. This is particularly true in terms of adoption. Leaders must adopt ICTs not only for their own competence—an antecedent condition for what is considered e-leadership, but choose, recommend, and support implementation of ICTs for their organizations/units to use. Leaders are also expected to become effective in dealing and navigating the challenges of leading within the digital space. At this moment, there are two pertinent literatures: the technology adoption literature and the enterprise resource planning literature—which can be considered an important special case of leadership change management literature—and which could provide the theoretical basis for developing a unified theoretical perspective on e-leadership. This article provides a framework and propositions to connect these literatures by focusing on the effects of individual leader characteristics on the ICT adoption process from both a personal and enterprise-wide perspective. Study limitations and future research opportunities are outlined.  相似文献   
82.
Supported Rh catalysts have been developed for selective H2 production at low temperatures. Ethanol dehydration is favorable over either acidic or basic supports such as γ-Al2O3 and MgAl2O4, while ethanol dehydrogenation is more favorable over neutral supports. CeO2–ZrO2-supported Rh catalysts were found to be especially effective for hydrogen production. We focused on a support prepared by a co-precipitation method having composition Ce0.8Zr0.2O2. A 2%Rh/Ce0.8Zr0.2O2 catalyst, prepared via impregnation without pre-calcination of support, exhibited the highest H2 yield at 450 °C among various supported Rh catalysts evaluated in this study. This may be due to both the strong interaction between Rh and Ce0.8Zr0.2O2 and the high oxygen transfer rate favoring reforming of acetaldehyde instead of methane production.  相似文献   
83.
In this paper we propose an optimized version, at the end-points, of the Akima's interpolation method for experimental data fitting. Comparing with the Akima's procedure, the error estimate, in terms of the modulus of continuity, is improved. Similarly, we optimize at the end points the Catmull–Rom's cubic spline. The properties of the obtained splines are illustrated on a numerical experiment.  相似文献   
84.
Despite the technological progress of the last decade, dental caries is still the most frequent oral health threat in children and adults alike. Such a condition has multiple triggers and is caused mainly by enamel degradation under the acidic attack of microbial cells, which compose the biofilm of the dental plaque. The biofilm of the dental plaque is a multispecific microbial consortium that periodically develops on mammalian teeth. It can be partially removed through mechanical forces by individual brushing or in specialized oral care facilities. Inhibition of microbial attachment and biofilm formation, as well as methods to strengthen dental enamel to microbial attack, represent the key factors in caries prevention. The purpose of this study was to elaborate a cold plasma-based method in order to modulate microbial attachment and biofilm formation and to improve the retention of fluoride (F) in an enamel-like hydroxyapatite (HAP) model sample. Our results showed improved F retention in the HAP model, which correlated with an increased antimicrobial and antibiofilm effect. The obtained cold plasma with a dual effect exhibited through biofilm modulation and enamel strengthening through fluoridation is intended for dental application, such as preventing and treating dental caries and enamel deterioration.  相似文献   
85.
Biofilms formed by fungal organisms are associated with drastically enhanced resistance against most antimicrobial agents, contributing to the persistence of the fungi despite antifungal therapy. The purpose of this study is to combine the unique properties of nanoparticles with the antimicrobial activity of the Rosmarinus officinalis essential oil in order to obtain a nanobiosystem that could be pelliculised on the surface of catheter pieces, in order to obtain an improved resistance to microbial colonization and biofilm development by Candida albicans and C. tropicalis clinical strains. The R. officinalis essential oils were extracted in a Neo-Clevenger type apparatus, and its chemical composition was settled by GC-MS analysis. Functionalized magnetite nanoparticles of up to 20 nm size had been synthesized by precipitation method adapted for microwave conditions, with oleic acid as surfactant. The catheter pieces were coated with suspended core/shell nanoparticles (Fe3O4/oleic acid:CHCl3), by applying a magnetic field on nanofluid, while the CHCl3 diluted essential oil was applied by adsorption in a secondary covering treatment. The fungal adherence ability was investigated in six multiwell plates, in which there have been placed catheters pieces with and without hybrid nanoparticles/essential oil nanobiosystem pellicle, by using culture-based methods and confocal laser scanning microscopy (CLSM). The R. officinalis essential oil coated nanoparticles strongly inhibited the adherence ability and biofilm development of the C. albicans and C. tropicalis tested strains to the catheter surface, as shown by viable cell counts and CLSM examination. Due to the important implications of Candida spp. in human pathogenesis, especially in prosthetic devices related infections and the emergence of antifungal tolerance/resistance, using the new core/shell/coated shell based on essential oil of R. officinalis to inhibit the fungal adherence could be of a great interest for the biomedical field, opening new directions for the design of film-coated surfaces with antibiofilm properties.  相似文献   
86.
This paper presents a NC toolpath generation strategy with tool engagement control for arbitrarily complex discrete part geometry, which reduces machining time and tool wear and can be used in high speed machining. The toolpath computation is based on image models for design part, raw stock and cutting tool, and involves pixel-based simulation of the milling process. Simulation results and comparison with existing methods are presented.  相似文献   
87.
This paper presents a VHDL-based simulated fault injection (SFI) methodology for quantum circuits. The main objective is to attain a high error modeling capability at a technology independent level. For this purpose, gate level simulation models for quantum circuits have been developed using VHDL. The proposed methodology relies on specific techniques inspired from the simulated fault injection techniques developed for classical CMOS circuits: saboteurs and mutants. In order to perform the simulation campaigns, a library of quantum gates and simulated fault injection components has been developed. The simulation results show that a wide range of quantum faults and error models has been addressed. Furthermore, a comparison between the two SFI techniques is presented.  相似文献   
88.
Ad-hoc and sensor networks are a well-studied area which gained a lot of attention in the research in the last decades. Two of the problems of battery-powered radio devices are limited transmitter power and finite amount of energy. This paper continues the path opened by the development of a new technology for radio communication which allows cluster communication beyond the horizon of each individual transmitter and the distribution of power need among the modules forming a cluster. This in terms decreases the average power need per device and contributes to a longer lifetime of the entire network.  相似文献   
89.
Results of switching behavior of the improper ferroelectric LuFeO3 are presented. Using a model set of films prepared under controlled chemical and growth-rate conditions, it is shown that defects can reduce the quasi-static switching voltage by up to 40% in qualitative agreement with first-principles calculations. Switching studies show that the coercive field has a stronger frequency dispersion for the improper ferroelectrics compared to a proper ferroelectric such as PbTiO3. It is concluded that the primary structural order parameter controls the switching dynamics of such improper ferroelectrics.  相似文献   
90.
We present the synthesis of nano-graphene structures with large surface areas and high purity over a high-yield Fe:Mo:MgO catalytic system. Two different hydrocarbon sources, acetylene and methane, were used, and their role in determining the size and morphology of the few-layer graphene sheets was studied. In addition, varying the active metal loading of the catalyst system influenced the formation and type of the resulting carbon nano-structures, e.g., carbon nanotubes or few-layer graphene. Growth of nano-graphene sheets was detected after only 5-min reaction time over this multifunctional catalytic system. High purity and crystalline graphene structures were synthesized indicating another advantage of using this particular catalyst system. This catalytic chemical vapor deposition can be scaled up for large-scale few-layer graphene production.  相似文献   
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