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31.
Tanzania is the second largest country in East Africa with about 50 million inhabitants in 2014, and it is also considered as one of the poorest countries in the world. The country strongly depends on agriculture production. Like many other poor countries in sub-Saharan Africa, Tanzania sees food security as a central part of development and poverty reduction efforts. This work aims to investigate the opportunities and constraints of implementing a policy of “Kitchen Gardens” as a practice for two regions of Tanzania. The research was carried out with a qualitative approach through a first round of semi-structured interviews using a Scaling up Assessment Tool (ScalA), and a second round with a questionnaire survey, using a Scaling up Assessment Tool for Food Security (ScalA-FS) by Tanzanian and German experts from the Trans-SEC project. The experts assessed implementation suitability and the institutional requirements of Kitchen Garden across the food value chains in two Tanzanian regions with different climate regions, namely Dodoma (semi-arid) and Morogoro (sub-humid). Kitchen Garden assessments did not differ significantly between these regions. The ScalA tools provided a range of statements that allowed an overview of the structural situation to be obtained, which could enable Kitchen Garden activity to be incentivized and scaled up. However, a number of specific aspects, potentials, challenges, and likely bottlenecks of implementation related to their feasibility and institutional requirements, were indicated, which should be carefully monitored during implementation. Adopting the recommended strategies could help to close gaps in implementation, enhance community empowerment and social network development, reduce food insecurity and improve the health of the communities.  相似文献   
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Guidelines on authorship requirements are common in biomedical journals but it is not known how authorship is defined by journals and scholarly professional organizations across research disciplines. Prevalence of authorship statements, their specificity and tone, and contributions required for authorship were assessed in 185 journals from Science Citation Index (SCI) and Social Science Citation Index (SSCI), 260 journals from Arts & Humanities Citation Index (A&HCI) and 651 codes of ethics from professional organizations from the online database of the Center for the Study of Ethics in the Profession, USA. In SCI, 53?% of the top-ranked journals had an authorship statement, compared with 32?% in SSCI. In a random sample of A&HCI-indexed journals, only 6?% of the journals addressed authorship. Only 71 (11?%) codes of ethics carried a statement on authorship. Almost all journals had defined authorship criteria compared with 33?% of the ethics codes ( $ \chi_{1}^{2} $ ?=?75.975; P?<?0.001). The tone of the statements in the journals was aspirational, whereas ethics codes used a normative language for defining authorship ( $ \chi_{1}^{2} $ ?=?51.709, P?<?0.001). Journals mostly required both research and writing contributions for authorship, while two-thirds of the ethics codes defined only research as a mandatory contribution. In conclusion, the lack of and variety of authorship definitions in journals and professional organizations across scientific disciplines may be confusing for the researchers and lead to poor authorship practices. All stakeholders in research need to collaborate on building the environment where ethical behaviour in authorship is a norm.  相似文献   
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(1) Background: Over the past 10 years, a number of scientific studies have demonstrated the therapeutic potential of cannabinoid compounds present in the Cannabis Sativa and Indica plants. However, their role in mechanisms leading to neurodegeneration following cerebral ischemia is yet unclear. (2) Methods: We investigated the effects of Cannabis extracts (Bedrocan, FM2) or selected cannabinoids (Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), and cannabigerol) in rat organotypic hippocampal slices exposed to oxygen-glucose deprivation (OGD), an in vitro model of forebrain global ischemia. Cell death in the CA1 subregion of slices was quantified by propidium iodide fluorescence, and morphological analysis and tissue organization were examined by immunohistochemistry and confocal microscopy. (3) Results: Incubation with the Bedrocan extract or THC exacerbated, whereas incubation with the FM2 extract or cannabidiol attenuated CA1 injury induced by OGD. Δ9-THC toxicity was prevented by CB1 receptor antagonists, the neuroprotective effect of cannabidiol was blocked by TRPV2, 5-HT1A, and PPARγ antagonists. Confocal microscopy confirmed that CBD, but not THC, had a significant protective effect toward neuronal damage and tissue disorganization caused by OGD in organotypic hippocampal slices. (4) Conclusions: Our results suggest that cannabinoids play different roles in the mechanisms of post-ischemic neuronal death. In particular, appropriate concentrations of CBD or CBD/THC ratios may represent a valid therapeutic intervention in the treatment of post-ischemic neuronal death.  相似文献   
37.
王倩 《现代装饰》2006,(6):10-17
一位著名设计师曾反复强调:家具有表情。 和空间,和光影,和线条相形相惜。  相似文献   
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A method of Structural Group Analysis (SGA) was used to characterize feed and liquid products from catalytic hydroprocessing using a commercial Ni-Mo catalyst. Comparison of the structural profiles revealed significant changes in the concentration of various structural groups. SGA is a promising tool for investigating chemical changes in complex reacting systems.  相似文献   
39.
The nanomechanical deformations on glass surfaces near the elastic–plastic load boundary have been measured on various glasses by nanoscratching using an atomic force microscope (AFM) to mimic the mechanical interactions of polishing particles during optical polishing. Nanoscratches were created in air and aqueous environments using a 150‐nm radius diamond‐coated tip on polished fused silica, borosilicate, and phosphate glass surfaces; the topology of the nanoscratches were then characterized by AFM. Using load ranges expected on slurry particles during glass polishing (0.05–200 μN), plastic‐type scratches were observed with depths in the nm range. Nanoscratching in air generally showed deeper & narrower scratches with more pileup compared to nanoscratching in water, especially on fused silica glass. The critical load needed to observe plastic deformation was determined to range from 0.2–1.2 μN for the three glasses. For phosphate glass, the load dependence of the removal depth was consistent with that expected from Hertzian mechanics. However, for fused silica and borosilicate glass in this load range, the deformation depth showed a weak dependence with load. Using a sub‐Tg annealing technique, material relaxation was observed on the nanoscratches, suggesting that a significant fraction of the deformation was due to densification on fused silica and borosilicate glass. Repeated nanoscratching at the same location was utilized for determining the effective incremental plastic removal depth. The incremental removal depth decreased with increase in number of passes, stabilizing after ~10 passes. In water, the removal depths were determined as 0.3–0.55 nm/pass for fused silica, 0.85 nm/pass for borosilicate glass, and 2.4 nm/pass for phosphate glass. The combined nanoscratching results were utilized to define the composite removal function (i.e., removal depth) for a single polishing particle as a function of load, spanning the chemical to the plastic removal regimes. This removal function serves as an important set of parameters in understanding material removal during polishing and the resulting workpiece surface roughness.  相似文献   
40.
Glass optics with ultra‐low roughness surfaces (<2 Å rms) are strongly desired for high‐end optical applications (e.g., lasers, spectroscopy, etc.). The complex microscopic interactions that occur between slurry particles and the glass workpiece during optical polishing ultimately determine the removal rate and resulting surface roughness of the workpiece. In this study, a comprehensive set of 100 mm diameter glass samples (fused silica, phosphate, and borosilicate) were polished using various slurry particle size distributions (PSD), slurry concentrations, and pad treatments. The removal rate and surface roughness of the glasses were characterized using white light interferometry and atomic force microscopy. The material removal mechanism for a given slurry particle is proposed to occur via nano‐plastic deformation (plastic removal) or via chemical reaction (molecular removal) depending on the slurry particle load on the glass surface. Using an expanded Hertzian contact model, called the Ensemble Hertzian Multi‐gap (EHMG) model, a platform has been developed to understand the microscopic interface interactions and to predict trends of the removal rate and surface roughness for a variety of polishing parameters. The EHMG model is based on multiple Hertzian contacts of slurry particles at the workpiece–pad interface in which the pad deflection and the effective interface gap at each pad asperity height are determined. Using this, the interface contact area and each particle's penetration, load, and contact zone are determined which are used to calculate the material removal rate and simulate the surface roughness. Each of the key polishing variables investigated is shown to affect the material removal rate, whose changes are dominated by very different microscopic interactions. Slurry PSD impacts the load per particle distribution and the fraction of particles removing material by plastic removal. The slurry concentration impacts the areal number density of particles and fraction of load on particles versus pad. The pad topography impacts the fraction of pad area making contact with the workpiece. The glass composition predominantly impacts the depth of plastic removal. Also, the results show that the dominant factor controlling surface roughness is the slurry PSD followed by the glass material's removal function and the pad topography. The model compares well with the experimental data over a variety of polishing conditions for both removal rate and roughness and can be extended to provide insights and strategies to develop practical, economic processes for obtaining ultra‐low roughness surfaces while simultaneously maintaining high material removal rates.  相似文献   
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