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Clean Technologies and Environmental Policy - In recent years, an increase in the chicken meat process industry has been growing quickly, which brings a large amount of difficult to process waste,...  相似文献   
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The influence of the basalt powder (BP) on mechanical properties as well as on thermal stability and flammability of the isotactic polypropylene (iPP) composites was investigated. Thermo‐mechanical stability of the pure polypropylene and composite materials containing from 5 up to 40 wt% BP was defined in static and dynamic testing conditions with the use of the heat distortion temperature measurement, vicat softening point temperature test, and dynamic mechanical thermal analysis. All measurements showed, unequivocally, a significant improvement of thermo‐mechanical stability of the composite materials which was directly related to an increasing amount of inorganic filler. A research conducted on the mechanical properties revealed that stiffness and hardness of polypropylene‐based composites was affected by the addition of the filler, leading to a strong increase of both mechanical parameters. Moreover, the application of thermogravimetric analysis and cone calorimetry measurements allowed to determine the composites with highest thermal stability, which was dependent on the concentration of the filler. Changes observed in the polypropylene‐based composites properties were related to an increase of thermal diffusivity caused by presence of the BP measured by modified Angstrom method. POLYM. ENG. SCI., 59:E71–E79, 2019. © 2018 Society of Plastics Engineers  相似文献   
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Anticholinesterase activities of mashes produced using wheat (‘Wheat Pale’) or barley malts (‘Pilsner’, ‘Pale Ale’, ‘Munich Light’, ‘Carahell’ or ‘Carared’) were studied by spectrophotometric method. The highest inhibition of acetylcholinesterase and butyrylcholinesterase was observed at 52 °C and/or 64 °C, followed by a decrease or stabilization of the activity at 72 °C. Changes in the total phenolics content in the test mashes were correlated with changes in the acetylcholinesterase and/or butyrylcholinesterase activities. Phenolic acids were singled out from phenolic compounds for more detailed studies owing to their simplicity and structural similarity to well‐known cholinesterase inhibitors. The main phenolic acids in the test malts were ferulic, gallic, p‐coumaric and vanillic acids followed by chlorogenic, caffeic, syringic, p‐OH‐benzoic, sinapic and protocatechuic acids. The anticholinesterase activities of the phenolic acids were studied using model standard solutions at concentrations similar to the maximal content of these compounds in the test mashes. Among the phenolic acids, p‐coumaric acid had the largest share in the anticholinesterase activity, even though it was present in the test mashes at a significantly lower concentration (~0.38 mm L?1) than ferulic acid (~1.00 mm L?1). Sinapic acid and p‐OH‐benzoic acid (0.03 and 0.01 mm L?1, respectively) were equally efficient inhibitors as ferulic acid at ~1.00 mm L?1. This preliminary study should be extended to other phenolic compounds from malt (wort) in the near future. Copyright © 2012 The Institute of Brewing & Distilling  相似文献   
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Persistent organic pollutants (POPs) are environmental and food-related contaminants of global public health concern and known to be carcinogenic and endocrine disruptors. Their monitoring is essential, and an easy-to-use, rapid, and affordable multianalyte screening method with simplified sample preparation can be a valuable tool prior to instrumental analysis. For this purpose, a flow cytometric immunoassay (FCIA), based on a spectrally encoded microbeads technology, was developed for the multiplex detection of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (BDEs) in buffer and fish extracts. The sensitivities of the assays in the three-plex FCIA format were similar to the individual FCIAs for the marker compounds benzo[a]pyrene (BaP), 3,3',4,4'-tetrachlorobiphenyl (PCB77), and 2,2',4,4'-tetrabromodiphenyl ether (BDE47) in buffer with IC(50) values of 0.4, 20, and 2 μg L(-1), respectively. Apart from the three markers, we could detect at least 14 other POPs. Extracts of fish with different fat content, prepared with a simplified extraction and cleanup procedure, had an insignificant influence on the overall three-plex FCIA performance, with the exception of some impact on the PAHs detection. The performance of the three-plex FCIA, in combination with the simple extraction procedure, is adequate for regulatory control in accordance with the required limits.  相似文献   
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Scientometrics - Aerosol water is a master component of atmospheric aerosols and a medium that enables all aqueous-phase reactions occurring in the atmosphere. This integral chemical compound of...  相似文献   
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In this case study, a food supplement with declared content of sea buckthorn oil was investigated since it was suspected to be adulterated by sunflower oil. Polar and non-polar fractions extracted from oil supplement were analyzed and compared with authentic sea buckthorn and sunflower oils examined in the same way. Three different analytical platforms were used in order to characterize these samples: (i) ambient mass spectrometry consisting of direct analysis in real time (DART) ion source coupled to quadrupole time-of-flight mass spectrometry (Q-TOF MS); (ii) ultra performance liquid chromatography (UHPLC) coupled to quadrupole time-of-flight mass spectrometry, and (iii) high-performance liquid chromatography coupled to diode array detector (HPLC-DAD). The fingerprints of polar and non-polar extracts, regardless they were obtained by DART-HRMS and/or UHPLC-HRMS, were almost identical with those of sunflower “reference” oil. The last of employed techniques, HPLC-DAD, provided complementary information on the occurrence of various visible light-absorbing compounds. While a rich carotenoid profile was shown in sea buckthorn oil, dominated by β-carotene, lutein, and lycopene, the color of the suspected sample was caused only by high concentration of β-carotene. In principle, these techniques proved to be suitable and complementary tools for oil authentication and allowed an oil supplement to be rapidly verified.  相似文献   
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