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101.
Particle size distributions of light-duty vehicle brake wear debris are reported with careful attention paid to avoid sampling biases. Electrical low-pressure impactor and micro-orifice uniform deposit impactor measurements yield consistent size distributions, and the net particulate matter mass from each method is in good agreement with gravimetric filter measurements. The mass mean diameter of wear debris from braking events representative of urban driving is 6 microm, and the number-weighted mean is 1-2 microm for three currently used classes of lining materials: low metallic, semimetallic, and non-asbestos organic (NAO). In contrast, the wear rates are very material dependent, both in number and mass of particles, with 3-4 times higher emissions observed from the low metallic linings as compared to the semimetallic and NAO linings. Wind tunnel and test track measurements demonstrate the appearance of micron size particles that correlate with braking events, with approximately 50% of the wear debris being airborne for the test vehicle in this study. Elemental analysis of the wear debris reveals a consistent presence of the elements Fe, Cu, and Ba in both dynamometer and test track samples.  相似文献   
102.
Extraction of As, Cd, Cu, Mn, Ni and Ti from two white as well as from one brown rice samples was studied by inductively coupled plasma sector field mass spectrometry (ICP-SF-MS). Samples were subjected to cold and hot water extraction (rice mass to deionised water volume ratio = 1:6, and 1:3, respectively). The discarded liquids were freeze-dried and digested by microwave-assisted digestion. About 50% of the content of the investigated elements could be extracted from the white rice. In case of the brown rice, the boiling water contained As, Cd, Ni and Ti in significant percentages. Elemental distributions in the rice grains determined by synchrotron radiation confocal micro-X-ray fluorescence analysis revealed that a surface layer having a thickness of about 80 μm is the richest region in elements. Ti was detectable only in this so-called skin region. Good correlation was observed for the extraction of As, Mn, Ni and Ti by the above-mentioned two techniques. Thus, in regions affected by heavy metal and other toxic element contamination, those rice dishes would be preferred whose preparation should need abundant amounts of water for washing and cooking, which later should be discarded.  相似文献   
103.
Phenolic profiles of nine red fruit commercial juice concentrates were characterised by means of high -performance liquid chromatography–diode array detection–mass spectrometry–mass spectrometry. Flavonoids such as anthocyanins, flavonols, hydroxycinnamic acid derivatives, stilbenoids, flavan 3-ols, ellagic acid derivatives, and other phenolic acids, were both identified and quantified in chokeberry, elderberry, blackcurrant and redcurrant, strawberry, red grape, cherry, plum, and raspberry commercial juice concentrates. Once the characterisation was carried out, the antioxidant capacity of each concentrate was assessed in vitro by means of two different methods: the 2,2-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (Trolox equivalent antioxidant capacity) method and the 2,2-diphenyl-1-picrylhydrazyl radical method. Elderberry, chokeberry and blackcurrant concentrates were the richest in total phenolics and they had the strongest antioxidant capacity; therefore, these three juices may have huge interest as ingredients in the design of functional juices.  相似文献   
104.
Sea salmon is a very appreciated seafood. The aim of this work was to analyze changes in lipid and protein fractions of minced muscle during chilled storage (1 ± 1 °C). Lipid oxidation was important during the first 6 days of storage according to 2‐thiobarbituric acid (TBA) values determined, decreasing mainly ω3 22:6 fatty acid content. Lipid hydrolysis was evident after 9 days of storage. Interaction compounds between oxidation products and other cellular components were analyzed by fluorescence measurements. The results obtained showed evidence of the formation of interaction products involved, mainly polar components such as proteins. Decreases in myosin and actin thermal stability and myosin denaturation were recorded by differential scanning calorimetry. Solubility of total and myofibrillar proteins decreased after 6 days of storage. The electrophoretic profile of soluble fractions showed an increase in the intensity of bands corresponding to low‐molecular‐weight polypeptides and a decrease in high‐molecular‐weight species. Available lysine content did not change during chilled storage. Copyright © 2007 Society of Chemical Industry  相似文献   
105.
Summary The flavonoids present in ten selected samples of La Alcarria honey with different pollen compositions have been HPLC analysed in order to establish if correlations between botanical origin and flavonoid profiles are possible. A common flavonoid pattern is observed in the different samples showing that pollen is not the main source of honey flavonoids. A close correlation between the flavonoid patterns of honey flavonoids and propolis flavonoids has been found suggesting that flavonoid analysis could be more useful in geographical origin determinations than in botanical origin studies.
Flavonoide des La-Alcarria-Honigs Eine Studie ihres botanischen Ursprungs
Zusammenfassung Die Flavonoide in Proben in Alcarria-Honig mit unterschiedlicher Pollenzusammensetzung wurden untersucht, um Kortrelationen zwischen dem botanischen Ursprung und den möglichen Flavonoiden zu finden. In den verschiedenen Proben wurde ein Flavonoid-Muster gefunden, wobei der Pollen nicht die Hauptquelle der Honigflavonoide ist. Es wurde jedoch eine enge Korrelation zwischen den Flavonoid-Mustern des Honigs und des Bienenkittharzes gefunden, was für die geographische Herkunft wichtiger ist als die botanische.
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106.
During the past two decades, landscape has frequently been conceptualized as a distancing way of seeing space. This conceptualization is normally traced back to the rise of capitalism and various modes of artistic representation, notably in the early modern Netherlands or the northern Low Countries. Yet recent scholarly interventions have asserted that landscape in the Low Countries and elsewhere in Europe was more than a distant scenery or an artistic mode of representation. Landscape also animated practices and ideologies of political representation, platial justice and custom. The platial notion of landscape and related concepts in the northern Low Countries around 1600 is focused upon, bringing out the intimate relationships between land, water and diverging ideals and practices of justice. It is argued that artistic landscape representation provided ways to reflect upon spatio-political developments in the Netherlands. Finally, there is a brief consideration of how these theoretical and historical issues resonate with modern thinking about landscape in physical planning.  相似文献   
107.
The 5-year relative survival for patients with head and neck cancer, the seventh most common form of cancer worldwide, was reported as 67% in developed countries in the second decade of the new millennium. Although surgery, radiotherapy, chemotherapy, or combined treatment often elicits an initial satisfactory response, relapses are frequently observed within two years. Current surveillance methods, including clinical exams and imaging evaluations, have not unambiguously demonstrated a survival benefit, most probably due to a lack of sensitivity in detecting very early recurrence. Recently, liquid biopsy monitoring of the molecular fingerprint of head and neck squamous cell carcinoma has been proposed and investigated as a strategy for longitudinal patient care. These innovative methods offer rapid, safe, and highly informative genetic analysis that can identify small tumors not yet visible by advanced imaging techniques, thus potentially shortening the time to treatment and improving survival outcomes. In this review, we provide insights into the available evidence that the molecular tumor fingerprint can be used in the surveillance of head and neck squamous cell carcinoma. Challenges to overcome, prior to clinical implementation, are also discussed.  相似文献   
108.
The advance of efficient hydrogen-air combustion systems has increasingly become of interest in the framework of the development of fuel cell systems, especially for the automotive sector. Therefore, compact modulating systems are required, with the additional demand of low emissions, to be integrated in a fuel cell system. A modulating combustion system based on combustion within inert porous media and an integrated heat exchanger has been developed and investigated. The system is able to handle premixed combustion of lean H2/air mixtures at a surface load range of 1075 kW/m2-2150 kW/m2, and a global equivalence ratio of ?=0.5. The special hydrogen-air mixing concept eliminates the risk of flame flashback and enables operation with very low NOx emissions.  相似文献   
109.
The reduction of energy use in buildings is a major component of greenhouse gas mitigation policy and requires knowledge of the fabric and the occupant behaviour. Hence there has been a longstanding desire to use automatic means to identify these. Smart metres and the internet-of-things have the potential to do this. This paper describes a study where the ability of inverse modelling to identify building parameters is evaluated for 6 monitored real and 1000 simulated buildings. It was found that low-order models provide good estimates of heat transfer coefficients and internal temperatures if heating, electricity use and CO2 concentration are measured during the winter period. This implies that the method could be used with a small number of cheap sensors and enable the accurate assessment of buildings’ thermal properties, and therefore the impact of any suggested retrofit. This has the potential to be transformative for the energy efficiency industry.  相似文献   
110.
BACKGROUND: The aim of this study was to investigate the growth‐inhibiting efficacy of Drosera intermedia extracts (water, methanol and n‐hexane) against four food spoilage yeasts and five filamentous fungi strains responsible for food deterioration and associated with mycotoxin production, in order to identify potential antimycotic agents. RESULTS: The n‐hexane extract showed a broad activity spectrum against all tested microorganisms, followed, in activity, by the methanol and water extracts. The major component of the n‐hexane extract was purified using a solid‐phase extraction column and identified as plumbagin. Results show that high‐purity plumbagin can be produced from D. intermedia cultures following a simple and effective isolation procedure. A sample of purified plumbagin was tested against the same panel of microorganisms and high growth‐inhibiting capacity was observed. Minimum inhibitory concentrations less than 2 µg mL?1 were obtained against the filamentous fungi. In the case of the species Aspergillus fumigatus, A. niger and A. flavus , activities comparable to miconazole were obtained. CONCLUSION: The results obtained provided evidence of the antimycotic activity of plumbagin, suggesting that D. intermedia could be the source of an interesting compound for the food industry as an alternative to preservatives. Copyright © 2011 Society of Chemical Industry  相似文献   
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