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排序方式: 共有646条查询结果,搜索用时 31 毫秒
641.
Juliette Moreau Dr. Umberto Giovanella Dr. Jean‐Philippe Bombenger Dr. William Porzio Dr. Varun Vohra Laura Spadacini Dr. Giuseppe Di Silvestro Prof. Luisa Barba Dr. Gianmichele Arrighetti Dr. Silvia Destri Dr. Mariacecilia Pasini Dr. Michele Saba Dr. Fancesco Quochi Dr. Andrea Mura Prof. Giovanni Bongiovanni Prof. Mauro Fiorini Dr. Michela Uslenghi Dr. Chiara Botta Dr. 《Chemphyschem》2009,10(4):647-653
All‐organic nanostructured host–guest materials (see picture) show enhanced, tunable fluorescence due to a high concentration of dyes with controlled spatial and geometrical organization that allows controlled resonant energy transfer. Homogeneous films of deoxycholic acid host–guests, provide coatings that convert near‐UV light into blue light with an efficiency higher than that of the standard polymeric blends.
642.
Donatella Capitani Noemi Proietti Marco Gobbino Luigi Soroldoni Umberto Casellato Massimo Valentini Elisabetta Rosina 《Analytical and bioanalytical chemistry》2009,395(7):2245-2253
An integrated study of microclimate monitoring, IR thermography (IRT), gravimetric tests and portable unilateral nuclear magnetic
resonance (NMR) was applied in the framework of planning emergency intervention on a very deteriorated wall painting in San
Rocco church, Cornaredo (Milan, Italy). The IRT investigation supported by gravimetric tests showed that the worst damage,
due to water infiltration, was localized on the wall painting of the northern wall. Unilateral NMR, a new non-destructive
technique which measures the hydrogen signal of the moisture and that was applied directly to the wall, allowed a detailed
map of the distribution of the moisture in the plaster underlying the wall panting to be obtained. With a proper calibration
of the integral of the recorded signal with suitable specimens, each area of the map corresponded to an accurate amount of
moisture. IRT, gravimetric tests and unilateral NMR applied to investigate the northern wall painting showed the presence
of two wet areas separated by a dry area. The moisture found in the lower area was ascribed to the occurrence of rising damp
at the bottom of the wall due to the slope of the garden soil towards the northern exterior. The moisture found in the upper
area was ascribed to condensation phenomena associated with the presence of a considerable amount of soluble, hygroscopic
salts. In the framework of this integrated study, IRT investigation and gravimetric methods validated portable unilateral
NMR as a new analytical tool for measuring in situ and without any sampling of the distribution and amount of moisture in
wall paintings. 相似文献
643.
C Scapolla G Cangemi S Barco L Barbagallo D Bugnone A Maffia G Melioli A Profumo U Benatti G Damonte 《Journal of mass spectrometry : JMS》2012,47(7):816-824
The levels of urinary catecholamine metabolites, such as homovanillic acid (HVA) and vanillylmandelic acid, are routinely used as a clinical tool in the diagnosis and follow-up of neuroblastoma (NB) patients. Recently, in the Clinical Pathology Laboratory Unit of G. Gaslini Children Hospital, a commercial method that employs liquid chromatography coupled to electrochemical detection (LC-EC) has been introduced for the measurement of these metabolites in the routine laboratory practice. Using this LC-EC method, an unknown peak could be observed only in samples derived from NB patients. To investigate the nature of this peak, we used a combination of liquid chromatography-time-of-flight mass spectrometry (LC-TOF-MS) and liquid chromatography-ion trap tandem mass spectrometry (LC-IT-MS). The first approach was used to obtain the elemental composition of the ions present in this new signal. To get additional structural information useful for the elucidation of unknown compounds, the ion trap analyzer was exploited. We were able to identify not just one, but three unknown signals in urine samples from NB patients which corresponded to three conjugated products of HVA: HVA sulfate and two glucuronoconjugate isomers. The enzymatic hydrolysis with β-glucuronidase confirmed the proposed structures, while the selective alkaline hydrolysis allowed us to distinguish the difference between phenol- and acyl-glucuronide of HVA. The latter was the unknown peak observed in LC-EC separations of urine samples from NB patients. 相似文献
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646.
Umberto Zucchini 《Macromolecular Symposia》1993,66(1):25-42
A great deal of research and development efforts in Ziegler Natta catalysis has been put within the last ten years into the polyolefin industry. The exploitation of new catalysts, the introduction and consolidation of advanced polymerization process technologies and, finally, the development of a broader range and of a better tailoring of product grades, have made the polyolefin market an expression of a young, dynamic, technology-driven industry. In this context heterogeneous catalysts have played a key role. Many drawbacks of the catalysts of the previous generation have been overcome. However some problems have still to be solved in order to both further improve catalyst performance and reduce the residual areas of empiricism in catalyst design and manufacture. 相似文献