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91.
At present the analytical investigation of human consumption products, with special regard to the environmental and health connections, is basically important all over the world. Recently in several countries it was almost impossible to sell wine without a certificate of quality, based on modern, instrumental analytical methods. There is well-known medical–biological evidence, which has proved the antioxidant and vein wall-protecting effects of the wines in the case of frugal ingestion. On the other hand, they also play a part in the prevention of heart attacks. Regarding these biological effects the most important constituents of wines are the flavonoids, anthocyanidins, and their glycosides. Anthocyanins can be identified first of all in red wines. The organic constituents have characteristic antioxidant effects, which can play an important role in health protection. During our investigation we have studied the volatile and non-volatile organic compounds in different types of wines made in Eger and Tokay (Hungary). In our opinion these types of research projects have unique importance, from the economic viewpoint and in that they are not negligible in a national context. The separation and determination of volatile compounds was carried out by applying a Finnigan GSQ GC-MS apparatus and the non-volatile ones with HPLC-DAD and FAB MS techniques.  相似文献   
92.
Journal of Radioanalytical and Nuclear Chemistry - This study aims to investigate the radioactivity of adobe in Angola, where it is a widely used building material. Sixty samples have been...  相似文献   
93.
94.
Journal of Thermal Analysis and Calorimetry - The increasing numbers of used tyres constitute a serious threat to the natural environment. The progress made in recent years in the management of...  相似文献   
95.
96.
The paper describes the applicability of different characteristics (signatures) in nuclear safeguards and forensics for assessment of uranium material provenance in terms of production process. The study follows a uranium ore concentrate production from an ore to a U3O8 product. It turned out that rare-earth elemental pattern, radiochronometry (age of ore body and material production date), sulphur and organic impurities are useful to find out the origin or history of the material, while certain trace-elements and isotopics of Pb or Sr were found to be inconclusive. The results will be important to understand the signatures in nuclear safeguards and forensics.  相似文献   
97.
There was an emerging need at the Nuclear Analysis and Radiography Department of the Centre for Energy Research, Hungarian Academy of Sciences, Budapest to be able to perform low level radioactivity measurements of various samples from in-beam activation and from environmental studies. Important aspects of reusing the low-background chamber called DÖME, which had been unused for some years, were the development of an easily reusable radon-tight sample container and the setup of a measurement system capable of counting extended samples in close-in geometry. As a result of our efforts a special sample container made of HDPE (High-density Polyethylene) was developed, and it is proved that the probability of a radon loss larger than the 2 % of its radioactive decay constant is <95 %. Due to the lack of reference samples, containing the same radionuclides as the unknown sample, the absolute method of measuring the activity concentration of nuclides in the sample had to be applied, which implied the reliable determination of the full-energy peak efficiency. A method called efficiency transfer combined with the correction for true coincidence summing effects is proven to be providing appropriate results and applied.  相似文献   
98.
JPC – Journal of Planar Chromatography – Modern TLC - log P values of 14 biologically active (E)-3-(X-benzylidene)-2,3-dihydro-1-benzopyran-4-ones (3) have been determined by an...  相似文献   
99.
The synthesis of 3‐alkyl and arylapomorphines 1820 has been accomplished by using the Suzuki–Miyaura cross‐coupling reaction of vinyl‐ and allylhalide morphinanedienes or arylhalide apocodeines and arylboronic acids.  相似文献   
100.
Varga R  Eke Z  Torkos K 《Talanta》2011,85(4):1920-1926
In our study we have identified phase I metabolites of cardiovascular and anti-ulcer agents with the application of predictive multiple reaction monitoring (pMRM) methods with liquid-chromatography-triple-quadrupole mass spectrometry (LC-QQQ-MS) in surface water samples. Targeted accurate mass spectrometry measurements were also carried out for confirmation with liquid-chromatography-time-of-flight mass spectrometry (LC-TOF-MS). pMRM followed by a targeted accurate mass spectrometry measurement can provide a sound basis for the selection of metabolites to be included in analytical methods for the investigation of environmental load of pharmaceuticals. Using LC-QQQ-MS twenty-one metabolites could be identified with two independent transitions at the same retention time and six of them could also be confirmed with LC-TOF-MS.  相似文献   
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