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111.
Smart mobility is day by day becoming one of the crucial issues to address in order to reduce environmental impacts such as global warming, acidification, photochemical smog, among others. The growing concerns about urban air quality are the driving force for cleaner and more efficient transport systems. Several new transport technologies are being developed, in particular concerning electric vehicles, considered a suitable solution to urban air pollution problems. However, these vehicles require electric and electronic devices that might give rise to a new set of environmental problems in their production, operation and disposal phases. Are electric vehicles a really cleaner solution? This paper aims at answering this question, by comparing two kinds of vehicle, a lithium battery powered electric bike and a hydrogen-fuel cell operated one, using internal combustion engine vehicles as benchmark. The fuel cell bike uses a proton exchange membrane fuel cell (PEMFC) to convert hydrogen into electricity. In this study, Life Cycle Assessment is applied to evaluate the environmental burdens of the production of these two vehicles and compare their environmental performances per 100 km travelled. The study, not only includes vehicle road operation but also embraces production and distribution of bikes, electric battery, PEMFC and energy carriers (electricity and hydrogen) over the vehicle's entire lifetime. The LCA evaluation of the vehicle production phases shows that the construction of the H-bike results more impacting than the E-bike in all the considered categories due to the presence of more complex components technology. Instead, when the boundary is shifted to the operational phases of the vehicles including the energy carriers production, the situation is reversed and the environmental performance of the H-bike results better than the one of E-bike.  相似文献   
112.
The aim of this work is to evaluate biohydrogen production from agro-industrial wastewaters and by-products, by combining dark fermentation and microbial electrolysis in a two-step cascade process. Such coupling of both technologies constitutes a technological building block within a concept of environmental biorefinery where sustainable production of renewable energy is expected.Six different wastewaters and industrial by-products coming from cheese, fruit juice, paper, sugar, fruit processing and spirits factories were evaluated for the feasibility of hydrogen production in a two-step process. The overall hydrogen production when coupling dark fermentation and microbial electrolysis was increased up to 13 times when compared to fermentation alone, achieving a maximum overall hydrogen yield of 1608.6 ± 266.2 mLH2/gCODconsumed and a maximum of 78.5 ± 5.7% of COD removal.These results show that dark fermentation coupled with microbial electrolysis is a highly promising option to maximize the conversion of agro-industrial wastewaters and by-products into bio-hydrogen.  相似文献   
113.
In this paper the performances of an electronic nose based on metalloporphyrin‐coated quartz microbalance sensors and of an experienced panel of seven human assessors in the evaluation of gases derived from degradation reactions in tomatoes are presented and discussed. The performances are measured in terms of the capability of both systems to distinguish between samples of different quality coming from conventional and organic production systems. The study deals with the application of pattern recognition techniques based on either multivariate statistical methods (PCA, GPA) or artificial neural networks using a self‐organising map (SOM). The response pattern of the sensor array and the sensory data are analysed and compared using these methods. Similarities in the classification of the data by electronic nose and human sensory profiling are found. © 2000 Society of Chemical Industry  相似文献   
114.
Organoids are tiny, self-organized, three-dimensional tissue cultures that are derived from the differentiation of stem cells. The growing interest in the use of organoids arises from their ability to mimic the biology and physiology of specific tissue structures in vitro. Organoids indeed represent promising systems for the in vitro modeling of tissue morphogenesis and organogenesis, regenerative medicine and tissue engineering, drug therapy testing, toxicology screening, and disease modeling. Although 2D cell cultures have been used for more than 50 years, even for their simplicity and low-cost maintenance, recent years have witnessed a steep rise in the availability of organoid model systems. Exploiting the ability of cells to re-aggregate and reconstruct the original architecture of an organ makes it possible to overcome many limitations of 2D cell culture systems. In vitro replication of the cellular micro-environment of a specific tissue leads to reproducing the molecular, biochemical, and biomechanical mechanisms that directly influence cell behavior and fate within that specific tissue. Lineage-specific self-organizing organoids have now been generated for many organs. Currently, growing cardiac organoid (cardioids) from pluripotent stem cells and cardiac stem/progenitor cells remains an open challenge due to the complexity of the spreading, differentiation, and migration of cardiac muscle and vascular layers. Here, we summarize the evolution of biological model systems from the generation of 2D spheroids to 3D organoids by focusing on the generation of cardioids based on the currently available laboratory technologies and outline their high potential for cardiovascular research.  相似文献   
115.
116.
VDAC (voltage-dependent anion selective channel) proteins, also known as mitochondrial porins, are the most abundant proteins of the outer mitochondrial membrane (OMM), where they play a vital role in various cellular processes, in the regulation of metabolism, and in survival pathways. There is increasing consensus about their function as a cellular hub, connecting bioenergetics functions to the rest of the cell. The structural characterization of VDACs presents challenging issues due to their very high hydrophobicity, low solubility, the difficulty to separate them from other mitochondrial proteins of similar hydrophobicity and the practical impossibility to isolate each single isoform. Consequently, it is necessary to analyze them as components of a relatively complex mixture. Due to the experimental difficulties in their structural characterization, post-translational modifications (PTMs) of VDAC proteins represent a little explored field. Only in recent years, the increasing number of tools aimed at identifying and quantifying PTMs has allowed to increase our knowledge in this field and in the mechanisms that regulate functions and interactions of mitochondrial porins. In particular, the development of nano-reversed phase ultra-high performance liquid chromatography (nanoRP-UHPLC) and ultra-sensitive high-resolution mass spectrometry (HRMS) methods has played a key role in this field. The findings obtained on VDAC PTMs using such methodologies, which permitted an in-depth characterization of these very hydrophobic trans-membrane pore proteins, are summarized in this review.  相似文献   
117.
Sardinian honeys obtained from different floral sources (Arbutus, Asphodelus, Eucalyptus, Thistle, and Sulla) were evaluated for their ability to inhibit tyrosinase and xanthine oxidase enzymes and for their antioxidant activity. Physicochemical parameters, total phenolic, and flavonoids content were also determined. Honey from Arbutus flowers had the highest antioxidant activity followed by Eucalyptus and Thistle ones. These three honeys showed good tyrosinase and xanthine oxidase inhibition properties. Thus, these Sardinian honeys could have a great potential as antioxidant sources for pharmaceutical and cosmetic applications.  相似文献   
118.
The complexity of skeletal pathologies makes use of in vivo models essential to elucidate the pathogenesis of the diseases; nevertheless, chondrocyte and osteoblast cell lines provide relevant information on the underlying disease mechanisms. Due to the limitations of primary chondrocytes, immortalized cells represent a unique tool to overcome this problem since they grow very easily for several passages. However, in the immortalization procedure the cells might lose the original phenotype; thus, these cell lines should be deeply characterized before their use. We immortalized primary chondrocytes from a Cant1 knock-out mouse, an animal model of Desbuquois dysplasia type 1, with a plasmid expressing the SV40 large and small T antigen. This cell line, based on morphological and biochemical parameters, showed preservation of the chondrocyte phenotype. In addition reduced proteoglycan synthesis and oversulfation of glycosaminoglycan chains were demonstrated, as already observed in primary chondrocytes from the Cant1 knock-out mouse. In conclusion, immortalized Cant1 knock-out chondrocytes maintained the disease phenotype observed in primary cells validating the in vitro model and providing an additional tool to further study the proteoglycan biosynthesis defect. The same approach might be extended to other cartilage disorders.  相似文献   
119.
A multi-channel continuous dynamic monitoring system has been installed in a centenary iron arch bridge on late November 2011. The historic infrastructure, completed in 1889 and crossing the Adda river about 50 km far from Milan, is the most important monument of XIX century iron architecture in Italy and is still used as roadway and railway bridge. The monitoring project follows a series of preliminary ambient vibration tests carried out on the bridge since June 2009. The paper describes the bridge structure and its dynamic characteristics identified from the experimental studies developed since 2009, the installed monitoring system and the software developed in LabVIEW for automatically processing the collected data. Subsequently, the tracking of automatically identified natural frequencies over a period of about 18 months is presented and discussed, highlighting the effects of environmental and operational conditions on the bridge dynamic characteristics as well as the detection of structural changes, mainly based on natural frequencies shifts.  相似文献   
120.
BACKGROUND: Twenty‐seven Italian honey samples of different floral origin were analysed for total phenolic and flavonoid contents by a spectrophotometric method and for antioxidant power and radical‐scavenging activity by the ferric‐reducing/antioxidant power (FRAP) and 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) assays respectively. In addition, the phenolic and flavonoid profiles were analysed using high‐performance liquid chromatography with UV detection (HPLC‐UV). RESULTS: The results of this study showed that honey contains copious amounts of phenolics and flavonoids. HPLC‐UV analysis showed a similar qualitative polyphenolic profile for all honey samples analysed. The main difference among samples was in the contribution of individual analytes, which was affected by floral origin. Total phenolic and flavonoid contents varied from 60.50 to 276.04 mg gallic acid equivalent kg?1 and from 41.88 to 211.68 mg quercetin equivalent kg?1 respectively. The antioxidant capacity was high and differed widely among samples. The FRAP value varied from 1.265 to 4.396 mmol Fe2+ kg?1, while the radical‐scavenging activity expressed as DPPH‐IC50 varied from 7.08 to 64.09 mg mL?1. Correlations between the parameters analysed were found to be statistically significant (P < 0.05). CONCLUSION: The present study shows that honey contains high levels of phenolics and flavonoids and that the distribution of these compounds is influenced by the honey's floral origin. Copyright © 2009 Society of Chemical Industry  相似文献   
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