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101.
Giorgi Kozhoridze Nikolai Orlovsky Leah Orlovsky Dan G. Blumberg 《International journal of remote sensing》2013,34(23):8784-8797
ABSTRACTHyperspectral remote sensing (RS) and images of various spatial resolution open new vistas for classification and mapping trees. These approaches would improve plant classification in a complex population of forest trees of diverse species, genera, and families, as well as monitoring commercial orchards. In this work, we used new RS indices for cellulose, lignin, wax, chlorophyll, carotenoid, and anthocyanin for plant species classification in natural forests and commercial orchards. For proof of concept, the indices were applied to the classification and mapping of various horticultural crop orchards, where error due to the spatial mixing of different trees is minimal. The classification accuracy of the maps varied between 65 and 82%. This wide range was a result of the following factors: The RS index used, the season, and the spatial resolution of the hyperspectral images. The classification quality was highest when the full set of RS indices was used. The effect of the wax index on accuracy was significant. Furthermore, seasonality played an important role in the classification; the target species were better resolved in spring than in the summer. The higher spatial resolution of the images does not necessarily yield better classification and mapping results; it appeared to be case-specific and greatly depended on the species/crop and the unique environment. 相似文献
102.
Stanislav Naryzhny Natalia Ronzhina Elena Zorina Fedor Kabachenko Maria Zavialova Viktor Zgoda Nikolai Klopov Olga Legina Rimma Pantina 《International journal of molecular sciences》2021,22(12)
Haptoglobin (Hp) is a blood plasma glycoprotein that plays a critical role in tissue protection and the prevention of oxidative damage. Haptoglobin is an acute-phase protein, its concentration in plasma changes in pathology, and the test for its concentration is part of normal clinical practice. Haptoglobin is a conservative protein and is the subject of research as a potential biomarker of many diseases, including malignant neoplasms. The Human Hp gene is polymorphic and controls the synthesis of three major phenotypes—homozygous Hp1-1 and Hp2-2, and heterozygous Hp2-1, determined by a combination of allelic variants that are inherited. Numerous studies indicate that the phenotype of haptoglobin can be used to judge the individual’s predisposition to various diseases. In addition, Hp undergoes various post-translational modifications (PTMs). Glioblastoma multiform (GBM) is the most malignant primary brain tumor. In our study, we have analyzed the state of Hp proteoforms in plasma and cells using 1D (SDS-PAGE) and 2D electrophoresis (2DE) with the following mass spectrometry (LC ES-MS/MS) or Western blotting. We found that the levels of α2- and β-chain proteoforms are up-regulated in the plasma of GBM patients. An unprocessed form of Hp2-2 (PreHp2-2, zonulin) with unusual biophysical parameters (pI/Mw) was also detected in the plasma of GBM patients and glioblastoma cells. Altogether, this data shows the possibility to use proteoforms of haptoglobin as a potential GBM-specific plasma biomarker. 相似文献
103.
Fee Klupp Christoph Kahlert Clemens Franz Niels Halama Nikolai Schleussner Naita M. Wirsik Arne Warth Thomas Schmidt Alexis B. Ulrich 《International journal of molecular sciences》2021,22(12)
Background: Granulin is a secreted, glycosylated peptide—originated by cleavage from a precursor protein—which is involved in cell growth, tumor invasion and angiogenesis. However, the specific prognostic impact of granulin in human colorectal cancer has only been studied to a limited extent. Thus, we wanted to assess the expression of granulin in colorectal cancer patients to evaluate its potential as a prognostic biomarker. Methods: Expressional differences of granulin in colorectal carcinoma tissue (n = 94) and corresponding healthy colon mucosa were assessed using qRT-PCR. Immunohistochemistry was performed in colorectal cancer specimens (n = 97), corresponding healthy mucosa (n = 47) and colorectal adenomas (n = 19). Subsequently, the results were correlated with histopathological and clinical patients’ data. HCT-116 cells were transfected with siRNA for invasion and migration assays. Results: Immunohistochemistry and qRT-PCR revealed tumoral over expression of granulin in colorectal cancer specimens compared to corresponding healthy colon mucosa and adenomas. Tumoral overexpression of granulin was associated with a significantly impaired overall survival. Moreover, downregulation of granulin by siRNA significantly diminished the invasive capacities of HCT-116 cells in vitro. Conclusion: Expression of granulin differs in colorectal cancer tissue, adenomas and healthy colon mucosa. Furthermore, granulin features invasive and migrative capabilities and overexpression of granulin correlates with a dismal prognosis. This reveals its potential as a prognostic biomarker and granulin could be a worthwhile molecular target for individualized anticancer therapy. 相似文献
104.
105.
Nikolai Kiesel Mohamed Bourennane Christian Kurtsiefer Harald Weinfurter D. Kaszlikowski W. Laskowski 《Journal of Modern Optics》2013,60(6-7):1131-1138
Abstract Multiphoton entanglement is the basis of many quantum communication schemes, quantum cryptographic protocols, and fundamental tests of quantum theory. For entangled three-qubit states it has been shown that there are two inequivalent classes of states, under stochastic local operations and classical communications. The classes are represented by the GHZ- and W-state. The GHZ-state has been used to prove Bell's theorem without inequality. Contrary to the GHZ-state, the W-state shows high robustness of entanglement against photon loss. Here we show the first experimental results on the observation of the polarization entangled three-photon W-state from spontaneous parametric down-conversion. 相似文献
106.
Dmitry V. Filosofov Nikolai A. Lebedev Alimardon V. Rakhimov Steffen Happel Frank Roesch 《溶剂提取与离子交换》2013,31(5):496-509
In this work, the interactions between the divalent alkaline earth elements (AEE) (Sr, Ba, Ra), the trivalent rare earth elements (REE) (Ce-Lu, Y), and Ac(III) with Sr-resin were investigated in the presence of HNO3, HCl, HBr, HClO4, and HPF6. Distribution coefficients of these ions on the Sr-resin were determined under batch-loading conditions. Lastly, online column separations were performed to demonstrate the utility of these systems. Substantial differences in the behavior of the ions in solutions comprised of the five different acids were observed. These differences can partly be explained by a combination of ion exchange (primary) and extraction (solvation) mechanisms. From a practical point of view, the Sr-resin/HClO4 or Sr-resin/HPF6 systems were demonstrated to be effective for the separation and purification of the different groups of the elements. 相似文献
107.
Aharon Oren Igor S. Plotnikov Sergey Sokolov Nikolai V. Aladin 《Lakes & Reservoirs: Research and Management》2010,15(3):223-236
In spite of significant differences in their sizes, depths, salinity and other properties, the Aral Sea and the Dead Sea share many features, as illustrated by a comparison of the histories of both water bodies. Fifteenth and early sixteenth century maps, based on the ‘Geography’ of Ptolemy, contain both lakes. The first successful limnological surveys of the lakes were made in the same year 1848, when Alexey Butakov explored the Aral Sea and William Lynch mapped the Dead Sea. Paintings and drawings by Taras Shevchenko (Aral Sea) and David Roberts (Dead Sea) document the landscapes around the lakes in the first half of the 19th century. The water balance of both lakes has been strongly negative in the past decades, leading to a decreased water surface area and volume for both lakes, their increased salinity and deterioration of their local infrastructures. Complex and expensive mitigation schemes have been proposed for both lakes, based on the import of large quantities of water from distant sources via canals or pipelines (i.e. Siberian rivers or Caspian Sea to supply water to the Aral Sea, Mediterranean Sea or Red Sea, to be connected with the Dead Sea). Less dramatic solutions to improve the local situations already have resulted in improved water quality in the Aral Sea, and partial restoration of its fisheries. In contrast, the Dead Sea remains much too saline to support higher forms of life. Nevertheless, a biblical prophecy predicts that even this most hypersaline of all lakes will eventually be teeming with fish of many kinds. 相似文献
108.
109.
Sverine Lavy Jeremie J. Miller Marek Paický Anne‐Sophie Rodrigues Frank Rominger Christoph Jkel Daniel Serra Nikolai Vinokurov Michael Limbach 《Advanced Synthesis \u0026amp; Catalysis》2010,352(17):2993-3000
The reductive formation of substituted anilines from amines and three well‐defined aryl‐ gold(III) complexes, i.e., dichloro(2,6‐lutidine)phen‐ ylgold(III) ( 2 ), dichloro(2,6‐lutidine)‐p‐tolylgold(III) ( 3 ), and chlorobis(triphenylphosphine)phenylgold(III) chloride ( 4 ) was studied. The reaction is stoichiometric in gold and represents a key step of a potential gold‐catalyzed intermolecular amination reaction of arenes. It proceeds smoothly with a broad range of N‐nucleophiles in the presence of sodium acetate (NaOAc) and enables the selective formation of N‐substituted anilines in good yields. A mechanistic pathway is proposed and discussed as well. 相似文献
110.
Chae J Jung S Woo S Baek H Ha J Song YJ Son YW Zhitenev NB Stroscio JA Kuk Y 《Nano letters》2012,12(4):1839-1844
The relation between macroscopic charge transport properties and microscopic carrier distribution is one of the central issues in the physics and future applications of graphene devices (GDs). We find strong conductance enhancement at the edges of GDs using scanning gate microscopy. This result is explained by our theoretical model of the opening of an additional conduction channel localized at the edges by depleting accumulated charge by the tip. 相似文献