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Quenched phosphorescence detection is a sensitive detection method recently introduced in capillary zone electrophoresis. It is based on the dynamic quenching interaction of the analytes (quenchers) with a phosphorophore, 1-bromo-4-naphthalenesulfonate (BrNS), present in the separation buffer. In this study, it is shown that this detection method can also be used in cyclodextrin-based electrokinetic chromatography (CD-EKC) despite the presence in the buffer solution of cyclodextrins, which are known to reduce the luminescence quenching rate constants. Experiments indicate that BrNS mainly resides in the aqueous phase, while the analytes are distributed between both phases. In principle, the observed quenching might arise from the interaction of BrNS with uncomplexed as well as complexed analytes. However, from the dependence of the fractional quenching on the capacity factor (the normalized fractional quenching was found to be equal to the fraction of analyte in the aqueous phase), it was concluded that only aqueous-phase quenching contributes significantly to the observed quenching. Nevertheless, separation and detection can be regarded as fully compatible, because the capacity factors encountered in CD-EKC are generally low (in this study they ranged from about 0.1 to 2.5). Indeed, with nitroaromatic compounds as the target analytes, limits of detection in the 10(-8) M range were achieved.  相似文献   
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This paper presents aut, a modern Automath checker. It is a straightforward re-implementation of the Zandleven Automath checker from the seventies. It was implemented about five years ago, in the programming language C. It accepts both the AUT-68 and AUT-QE dialects of Automath. This program was written to restore a damaged version of Jutting's translation of Landau's Grundlagen. Some notable features: It is fast. On a 1 GHz machine it will check the full Jutting formalization (736 K of nonwhitespace Automath source) in 0.6 seconds. Its implementation of -terms does not use named variables or de Bruijn indices (the two common approaches) but instead uses a graph representation. In this representation variables are represented by pointers to a binder. The program can compile an Automath text into one big Automath single line-style -term. It outputs such a term using de Bruijn indices. (These -terms cannot be checked by modern systems like Coq or Agda, because the -typed -calculi of de Bruijn are different from the -typed -calculi of modern type theory.)The source of aut is freely available on the Web at the address .  相似文献   
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Much work has been done in construction of petrogenetic grids for regional-scale metamorphic terrains, but low-pressure assemblages, such as contact aureoles, have been relatively ignored. This study has focused on developing a petrogenetic transect for a granitic aureole using a portable field spectrometer. Distribution of mineral assemblages, their modes, metamorphic zones, paragenetic sequences and isograds were mapped along a 4 km long transect. The transect starts at the fresh granite and cuts through the metamorphic contact aureole into the host rocks. Metamorphic reactions responsible for mineral changes were also defined. The method demonstrated potential in mineral mapping and the results could be used to support other methods like hyperspectral image analysis.  相似文献   
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This article investigates methods for achieving more general manipulation capabilities for mobile manipulation platforms, which produce legible behavior in human living environments. To achieve generality and legibility, we combine two control mechanisms. First of all, experience- and observation-based learning of skills is applied to routine tasks, so that the repetitive and stereotypical character of everyday activity is exploited. Second, we use planning, reasoning, and search for novel tasks which have no stereotypical solution. We apply these ideas to the learning and use of action-related places, to the model-based visual recognition and localization of objects, and the learning and application of reaching strategies and motions from humans. We demonstrate the integration of these mechanisms into a single low-level control system for autonomous manipulation platforms.  相似文献   
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A new method for the detection of pre-defined boundaries in single-band image data that uses a rotation-variant template matching (RTM) algorithm is presented. This algorithm matches a miniature image of a pre-defined boundary to image data at various orientations. The image pixels that match boundary criteria are reported in output imagery together with the rotation angle of the template. The method is applied to identify boundaries between hydrothermal alteration zones in processed airborne hyperspectral imagery, based on the presence of white mica minerals. Results show that boundaries identified with RTM are relatively free of noise and more coherent than those identified with, for instance, image slicing techniques. Identified boundaries can be used for image segmentation. The output of the RTM algorithm also provides information on the type of boundary, whether it is crisp or gradual. This information can be used to better characterize mineral variation in the alteration halo associated with fossil hydrothermal systems.  相似文献   
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Raman spectroscopy and X-ray fluorescence (XRF) spectroscopy are often used as complementary techniques that are well suited for the analysis of art objects because both techniques are fast, sensitive, and noninvasive and measurements can take place in situ. In most of these studies, both techniques are used separately, in the sense that the spectra are evaluated independently and single conclusions are obtained, considering both results. This paper presents a data fusion procedure for Raman and XRF data for the characterization of pigments used in porcelain cards. For the classification of the analyzed points of the porcelain cards principal component analysis (PCA) was used. A first attempt was made to develop a new procedure for the identification of the pigments using a database containing the fused Raman-XRF data of 24 reference pigments. The results show that the classification based on the fused Raman-XRF data is significantly better than the classifications based on the Raman data or the XRF data separately.  相似文献   
8.
Manipulating friction without applying high normal forces is important for an intestine inspection and intervention device in order to eliminate the risk of tissue damage. One possible solution is to generate friction by means of adhesive forces. The adhesive forces should be high to offer sufficient grip without needing high normal forces. The generated friction is then called adhesion-controlled and depends on the size of the area in contact. Adhesion-controlled friction is well known to be dominant at microscopic and molecular levels. According to this paper, adhesion-controlled friction can be applicable on the macroscopic scale as well and, more specifically, within a range of forces in which friction is usually considered to be load-controlled. The intestine inspection and intervention device manipulates the friction with the colonic wall by means of mucoadhesive films. In this way, grip with high static friction is achieved without the need to apply high normal forces and friction is altered by changing the size of the area of the mucoadhesive film. Friction theories on different scales are revisited and considered in order to understand the dominant phenomena and the principles associated with this macroscopic adhesion-controlled friction.  相似文献   
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Several non-supported oxidic compounds potentially present in a Cu/K/Mo/Cl catalyst (copper molybdates, potassium molybdates, and a mixed copper-potassium molybdate (K2Cu2(MoO4)3)) have been tested individually on their activity in the oxidation of a model soot (Printex-U, which non-catalytically oxidizes at 875 K). These oxidic compounds are active between 665 and 720 K, but only after establishment of ‘tight contact’ between the catalyst and soot in a ball mill. Without the ball mill procedure (‘loose contact’) these oxides are less active (the soot oxidation temperature is shifted to about 790 K), while a ZrO2 supported Cu/K/Mo/Cl catalyst still shows a high activity around 670 K. Hence, the ‘loose contact’ activity of the supported Cu/K/Mo/Cl catalyst is not explained by the presence of an active oxidic compound. DRIFT and XRD analyses have shown that addition of KCl to CuMoO4 (two compounds present within the Cu/K/Mo/Cl catalysts) followed by calcination at 950 K in air, eventually results in the formation of a mixed potassium-copper molybdate. Simultaneously several volatile copper, potassium and chlorine containing compounds (e.g. K2CuCl4) are formed. These copper and chlorine containing compounds possess a high ‘loose contact’ soot oxidation activity between 600 and 690 K. A catalytic cycle, involving Cu2OCl2, is proposed to explain the high ‘loose contact’ activity of copper chlorides and supported Cu/K/Mo/Cl catalysts. The activity of the latter catalyst will be maintained as long as Cu2OCl2 can be reformed by reaction of copper molybdates with KCl, which serves as a chlorine supplier.  相似文献   
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