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This paper describes a simple and inexpensive metallo-organic deposition (MOD) process for forming electrochromic tungsten oxide (WO3) films on glass. The thin films of WO3 were made by air firing (500–700°C) films from xylene/2-propanol solutions of bis-(di-n-octylammonium) tetratungstate, [(n-C8H17)2NH2]2[W4O13]. The process coats glass with undoped films ranging in colour from faint yellow to dark brown, and can be used to make gradients of these colours. The colour is determined by the firing parameters and results from residual carbon and tungsten suboxides in the film due to incomplete firing. Increased firing temperatures or longer firing times removes the carbon and produces films with higher crystallinity. Electrochemical doping with acid (H+) switches the colour gradient films to a uniformly blue colour.  相似文献   
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The World Wide Web(WWW) comprises a wide range of information, and it is mainly operated on the principles of keyword matching which often reduces accurate information retrieval. Automatic query expansion is one of the primary methods for information retrieval, and it handles the vocabulary mismatch problem often faced by the information retrieval systems to retrieve an appropriate document using the keywords. This paper proposed a novel approach of hybrid COOT-based Cat and Mouse Optimization (CMO) algorithm named as hybrid COOT-CMO for the appropriate selection of optimal candidate terms in the automatic query expansion process. To improve the accuracy of the Cat and Mouse Optimization (CMO) algorithm, the parameters are tuned with the help of the Coot algorithm. The best suitable expanded query is identified from the available expanded query sets also known as candidate query pools. All feasible combinations in this candidate query pool should be obtained from the top retrieved documents. Benchmark datasets such as the GOV2 Test Collection, the Cranfield Collections, and the NTCIR Test Collection are utilized to assess the performance of the proposed hybrid COOT-CMO method for automatic query expansion. This proposed method surpasses the existing state-of-the-art techniques using many performance measures such as F-score, precision, and mean average precision (MAP).

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Abstract: Recent evidence has demonstrated that nitrites play an important role in the cardiovascular system. Fennel (Foneiculum vulgare) seeds are often used as mouth fresheners after a meal in both the Indian sub‐continent and around the world. The present study aims to quantify the nitrite and nitrates in fennel seeds as well as elucidating the effect of fennel derived‐nitrites on vascular functions. Results from our study show that fennel seeds contain significantly higher amount of nitrites when compared to other commonly used post‐meal seeds. Furthermore our study confirmed the functional effects of fennel derived‐nitrites using in vitro and ex vivo models that describe the promotion of angiogenesis, cell migration, and vasorelaxation. We also showed that chewing fennel seeds enhanced nitrite content of saliva. Thus our study indicates the potential role of fennel derived‐nitrites on the vascular system. Practical Application: This study is focused on determining the effect of fennel‐derived nitrites on angiogenesis (the formation of new blood vessels from pre‐existing ones), cell migration, and vasorelaxation (dilation of blood vessels) thereby preserving cardiovascular health.  相似文献   
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Optically variable windows (smart windows), which control the transmission of light into buildings and vehicles, are of interest both for the control of solar heat load and for privacy applications. Such windows are likely to utilize electrochromic technology to achieve optical control. An electrochromic device consisting of a cathodically colouring tungsten trioxide (WO3) film, an anodically colouring Prussian blue (PB) film, and a polymer electrolyte was made. The polymer electrolyte was prepared from polyvinyl alcohol doped with H3PO4 and KH2PO4 to accommodate the conduction of both H+ and K+ ions. The electrochromic WO3 and PB films functioned in a complementary way such that the device was coloured or bleached by the application of –0.5 V or +0.5 V (WO3 films vs PB film), respectively. The spectral characteristics of the coloured device confirmed the complementary colouration of WO3 and PB in the device.  相似文献   
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A method is presented for the synthesis of RC 1-ports with a minimum possible number of capacitors, all of equal value and all connected to a common terminal of the 1-port. Such a realisation facilitates economical integrated- circuit fabrication and is of importance in integrated active RC 2-port synthesis.  相似文献   
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