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1.
A method for the preparation of high surface area coatings and its application towards fabrication of prospective composite electrocatalysts for hydrogen evolution is proposed. Exploratory studies with such a composite, (Ni/LaNiO3), as a hydrogen electrode in alkaline solutions indicate that it is a more active electrocatalyst than sintered or electrodeposited nickel. The electrocatalytic properties were found to be a strong function of the deposition parameters as well as of the history of the oxide powder.  相似文献   
2.
Angelina Altomare 《Polymer》2005,46(7):2086-2096
New host-guest systems were prepared by using poly(vinyl acetate) and different ethylene-vinyl acetate copolymers as polymeric hosts because of their good compatibility with polar molecules. Two symmetric azobenzene diesters, that is 4,4′-dicarboxyethylazobenzene and 4,4′-di(2-ethylhexyloxycarbonyl)azobenzene were selected as guests. Both solution casting and melt processing were adopted for the preparation of dispersion films that were thoroughly characterized by thermal analysis, UV-vis and FT-IR spectroscopy, and by polarized optical microscopy. The reported results indicate that solution casting afforded heterogeneous dispersions of dye microcrystals at guest concentrations larger than 0.3% whereas homogeneous colored films were obtained at lower dye contents. On the other hand, both melt processing and the presence of branched diester groups favored the dye dispersion within the polymer matrix. At 0.1% dye content, the adopted preparation technique did not appreciably affect the film properties. After 4-8 fold stretching, the host-guest films were analyzed by polarized light spectroscopy. Some of the investigated films displayed interesting polarization efficiency, potentially suited for the preparation of thin film polarizers.  相似文献   
3.
Summary There different legumes, chick peas, kidney beans, and lentils, were soaked and boiled in distilled water under normal and high pressure. The cooked legumes were kept at 35° C for 5 h, simulating catering systems, and the niacin contents were determined by HPLC. Data were obtained for raw and boiled legumes on both a wet weight and a dry matter basis. The niacin content of the raw legumes on a wet weight basis was always higher than that of the processed legumes, but on a dry matter basis there were small, though occasionally significant, increases in niacin content. In most cases simulated catering also led to a significant increase in the available niacin.
Gehalt an verfügbarem Niacin in verarbeiteten Hülsenfrüchten
Zusammenfassung Drei verschiedene Hülsenfrüchte, Kichererbsen, Schminkbohnen und Linsen, wurden in destilliertem Wasser eingeweicht und anschließend unter normalem und erhöhtem Druck gekocht. Zur Simulation eines Catering-Systemes wurden die gekochten Hülsenfrüchte 5 h bei 35 °C gelagert. In den rohen, den gekochten und den gelagerten Hülsenfrüchten wurde der Niacingehalt mittels Hochleistungsflüssigchromatographie (HPLC) bestimmt. Die erhaltenen Resultate zeigten, daß der Gehalt an verfügbarem Niacin, bezogen auf das Frischgewicht des Rohmaterials, durch den Kochprozeß in jedem Falle vermindert wird. Auf Trockensubstanz bezogen wurden kleine, zum Teil signifikante, Erhöhungen des Niacingehaltes gegenüber dem Rohmaterial beobachtet. Die Simulation von Catering-Bedingungen führte ebenfalls in den meisten Fällen zu einer signifikanten Erhöhung des verfügbaren Niacins.
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4.
International Journal of Computer Vision - Machine learning models are known to perpetuate and even amplify the biases present in the data. However, these data biases frequently do not become...  相似文献   
5.
Traceability is recognized to be important for supporting agile development processes. However, after analyzing many of the existing traceability approaches it can be concluded that they strongly depend on traditional development process characteristics. Within this paper it is justified that this is a drawback to support adequately agile processes. As it is discussed, some concepts do not have the same semantics for traditional and agile methodologies. This paper proposes three features that traceability models should support to be less dependent on a specific development process: (1) user-definable traceability links, (2) roles, and (3) linkage rules. To present how these features can be applied, an emerging traceability metamodel (TmM) will be used within this paper. TmM supports the definition of traceability methodologies adapted to the needs of each project. As it is shown, after introducing these three features into traceability models, two main advantages are obtained: 1) the support they can provide to agile process stakeholders is significantly more extensive, and 2) it will be possible to achieve a higher degree of automation. In this sense it will be feasible to have a methodical trace acquisition and maintenance process adapted to agile processes.  相似文献   
6.
The European Union Reference Laboratory (EURL) for Salmonella organises interlaboratory comparison studies on bacteriological detection of Salmonella in different matrices (veterinary, food and animal feed) amongst National Reference Laboratories for Salmonella of the 27 European Member States (EU-MS). The EURL also gives non-EU Member States (EU candidate countries, member countries of the European Free Trade Association (EFTA) and third countries from outside Europe) the opportunity to participate in these studies. The objective of the studies is to test the ability of the participating laboratories to detect Salmonella at different contamination levels in the various matrices. In addition a comparison is made between the prescribed method of the food and animal feed studies (ISO 6579: RVS and MKTTn) and the prescribed method of the veterinary studies (annex D of ISO 6579: MSRV).This article describes the performance of the individual laboratories in the interlaboratory comparison studies as organised by the EURL for Salmonella in the period 2004-2010.The performance of the majority of the NRLs improved during the course of the studies. Overall the NRL laboratories performed well and were able to detect Salmonella in the different tested matrices. After improvement of the samples, it was possible to define criteria for good performance in the studies organised since 2006. In the eight interlaboratory comparison studies organised in the period 2006–2010, 15 laboratories found in total 19 deviations of which eight concerned a false positive blank result. The other deviations concerned sensitivity problems (false negative results). After checking and improving several technical aspects, the underperforming participating laboratories were able to improve their performance in a follow-up study.  相似文献   
7.
8.
Photoresponsive macromolecules are of interest both as novel organic materials for applications in photodevices and as models for photomodulated biological processes. The presence in polymer chains of photosensitive groups and of chiral groups capable of inducing optical activity into the polymer is very useful for the analysis of photomodulated structural variations and allows storage of the light effect in the form of chiral information. Polypeptides bearing photochromic groups in the side chains are very convenient as the chiroptical properties of the peptide chromophore can be correlated to the backbone conformation. Thus polymers of L-aspartic acid, L-glutamic acid and L-lysine with azobenzene or stilbene groups attached covalently to the side chains are discussed in terms of photoinduced conformational changes and chiroptical information storage in the spectral region of the peptide and of the photoresponsive chromophore. Optically active photochromic macromolecules with hydrocarbon backbone, such as copolymers of (—)-menthyl acrylate with vinyl or acryloyl derivatives of azobenzene, stilbene and indolinospirobenzopyran, also show in some cases photodependence of chiroptical properties with evidence of at least local conformational changes as a consequence of light irradiation which can be used for chiral information.  相似文献   
9.
A key challenge for the improvement of clear cell renal cell carcinoma (ccRCC) management could derive from a deeper characterization of the biology of these neoplasms that could greatly improve the diagnosis, prognosis and treatment choice. The aim of this study was to identify specific miRNAs that are deregulated in tumor vs. normal kidney tissues and that could impact on the biology of ccRCC. To this end we selected four miRNAs (miR-21-5p, miR-210-3p, miR-185-5p and miR-221-3p) and their expression has been evaluated in a retrospective cohort of formalin-fixed paraffin-embedded (FFPE) tissues from 20 ccRCC patients who underwent surgical nephrectomy resection. miR-21-5p and miR-210-3p resulted the most significantly up-regulated miRNAs in this patient cohort, highlighting these onco-miRNAs as possible relevant players involved in ccRCC tumorigenesis. Thus, this study reports the identification of specific oncogenic miRNAs that are altered in ccRCC tissues and suggests that they might be useful biomarkers in ccRCC management.  相似文献   
10.
The interdisciplinary Tales of Things and electronic Memory (TOTeM) project investigates new contexts for augmenting things with stories in the emerging culture of the Internet of Things (IoT). Tales of Things is a tagging system which, based on two-dimensional barcodes (also called Quick Response or QR codes) and Radio Frequency Identification (RFID) technology, enables the capturing and sharing of object stories and the physical linking to objects via read and writable tags. Within the context of our study, it has functioned as a technology probe which we employed with the aim to stimulate discussion and identify desire lines that point to novel design opportunities for the engagement with personal and social memories linked to everyday objects. In this paper, we discuss results from fieldwork with different community groups in the course of which seemingly any object could form the basis of a meaningful story and act as entry point into rich inherent ‘networks of meaning’. Such networks of meaning are often solely accessible for the owner of an object and are at risk of getting lost as time goes by. We discuss the different discourses that are inherent in these object stories and provide avenues for making these memories and meaning networks accessible and shareable. This paper critically reflects on Tales of Things as an example of an augmented memory system and discusses possible wider implications for the design of related systems.  相似文献   
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