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61.
Sentiment analysis has become a very useful tool in recent times for studying people’s opinions, sentiments and subjective evaluation of any event of social and economic relevance, and in particular, policy decisions. The present paper proposes a framework for sentiment analysis using twitter data for the ’demonetization’ effort of the Government of India. The paper employs twitter data using Twitter API. The methodology of the paper involves collection of data from twitter from different cities of India using geolocation and preprocessing followed by a lexicon-based approach to analyse users’ sentiments over a period of five weeks preceding the policy announcement. In addition to this, the paper also attempts to analyse the sentiments of specific groups of people representing diverse interest groups.  相似文献   
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Cobalt acrylate (CoA2) has been treated with bisphenol‐A and epichlorohydrin to modify epoxy resins. It was cured with p‐acetylbenzilidene triphenyl arsonium ylide. The properties such as epoxide equivalent weight (equiv/100 g), molecular weight, hydrolyzable chlorine content increases whereas hydroxyl content, refractive index decreases in the presence of CoA2. The cured epoxy resins shows improve electrical conductivity due to the incorporation of CoA2 with epoxy resins. The influence of complex formation of CoA2 with either linkage of epoxy resins were investigated by spectroscopy. The decrease in Tg from differential scanning calorimetry support the improve in flexibility. The dispersion of cobalt in epoxy resins matrix was confirmed by scanning electron microscope. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
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This study describes a technique for reducing the computational effort for performing linear optimization while solving any geotechnical stability problem with the use of the lower bound finite-element limit analysis. In the proposed method, a lower order polygon is initially used to model the Mohr-Coulomb yield function; the order of the polygon refers to its total number of sides. The initial solution is used to identify the governing side of the yield polygon that lies nearest to the point defining the existing stress state. Subsequently, this governing side of the linearized yield polygon is replaced with a number of the relevant sides of the higher order polygon. Because all the sides of the higher order polygon for imposing the linearized yield constraints do not enter the formulation, the associated computational effort becomes much smaller. With the proposed algorithm, the collapse loads were determined for smooth and rough strip footing, and the computational results were found to be quite convincing.  相似文献   
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Electronic Commerce Research - There are many big data sources in Indonesia, for example, data from social media, financial transactions, transportation, call detail records, and e-commerce. These...  相似文献   
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Sodium alginate and carboxymethyl locust bean gum (CMLBG) were reticulated in an aqueous solution of AlCl3, and this novel interpenetrating network (IPN) hydrogel encapsulated about 93–98% glipizide. The degree of reticulation in the spherical IPN beads was confirmed by Fourier transform infrared spectroscopy, elemental analysis, neutralization equivalent determination, tensile strength testing, and differential scanning calorimetry analysis. An increase in the CMLBG weight ratio and the degree of crosslinking in the IPN was found to increase mean dissolution time of the encapsulated drug. The dissolution efficiency was found to be much higher in the medium at pH 7.4 than at pH 1.2. The swelling of IPN depended on the pH of the medium, and accordingly, monitored the drug release for a period of 8 h. The anomalous drug transport mechanism was presumed to be operative. High performance liquid chromatography (HPLC) analysis showed the drug's stability in the IPN during encapsulation. The IPN showed significant hypoglycemic activity on male Wistar rats for up to 10 h. This could be beneficial for diabetic patients for achieving control over blood glucose levels. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
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In the global effort to thwart antimicrobial resistance, lipopeptides are an important class of antimicrobial agents, especially against Gram‐negative infections. In an attempt to circumvent their synthetic complexities, we designed simple membrane‐active agents involving only one amino acid and two lipid tails. Herein we show that the use of two short lipid tails instead of a single long one significantly increases selective antibacterial activity. This study yielded several selective antibacterial compounds, and investigations into the properties of this compound class were conducted with the most active compound. Fluorescence spectroscopic studies revealed the capacity of the representative compound to cause depolarization and permeabilization of bacterial cell membranes. This membrane‐active nature of the compound imparts superior activity against persister cells, biofilms, and planktonic cells. Topical application of the compound decreased bacterial burden in mice inflicted with burn‐infections caused by Acinetobacter baumannii. We anticipate that the design principles described herein will direct the development of several antimicrobial agents of clinical importance.  相似文献   
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Bulletin of Engineering Geology and the Environment - Landslide susceptibility assessment (LSA) is a method used to reduce landslide vulnerability defined as landslide spatial prediction with the...  相似文献   
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Abstract  

Polymer supported Cu(II) catalyst was prepared, characterized and employed for the N-arylation and amination reaction of N–H heterocycles with aryl halides as well as arylboronic acids to afford the corresponding coupled products in good to excellent yields. This catalyst can be used several times with consistent catalytic activity.  相似文献   
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