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111.
112.
Azelate polyols of 2000 g mol?1 have been successfully prepared via esterification of renewable azelaic acid with linear diols containing different number of CH2 repeating units. Structure–property correlation of the azelate polyols had been evaluated in thermoplastic polyurethanes (TPUs). TPUs based on azelate polyols of longer chained linear diols with >4 CH2 repeat units retained higher degrees of crystallinity associated with the polyol soft segment. The ratio of hydrogen bonded urethane in the hard segment to free urethane phase mixed with the soft segment in the TPUs showed a complex oscillating dependence with increased number of CH2 repeating unit in the linear diols of azelate polyols. Correspondingly, static and dynamic properties of TPUs also showed the oscillatory dependence, whereby dynamic properties maximized with odd number of CH2 repeating unit and material strength maximized with even number of CH2 repeating unit. The results therefore can be used as guide to select appropriate azelate polyols to target specific TPU performance. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46258.  相似文献   
113.
The COSMO-RS model was used to screen potential ionic liquids for the separation of aqueous azeotropic mixtures 1-propanol?+?water and 2-propanol?+?water. A combination of 22 cations (involving imidazolium, pyridinium, pyrrolidinium, quinolinium, and ammonium) and 36 anions were investigated. The anions chloride [Cl] and dihydrogen phosphate [H2O4P] were found to strongly influence the vapor liquid equilibrium behavior, whereas the ammonium-based cations diethanol ammonium [(Et)2AMM]+ and tetra methyl ammonium [M4AMM]+ were the most promising cations. In addition, the study of mixing enthalpy and excess Gibbs free energy confirmed that the molecular interaction of ionic liquids with water was found to be much larger than that with alcohols 1-propanol and 2-propanol, indicating the presence of a strong hydrogen bonding between the ionic liquids and water. Further, the addition of ionic liquids to the alcohol–water mixture reduces the activity coefficient of water and increases the relative volatility of the mixture, facilitating easier separation. Ionic liquids [(Et)2AMM][Cl], [(Et)2AMM][H2O4P], [M4AMM][Cl], and [M4AMM][H2O4P] are expected to be effective entrainers for the separation of the industrially important 1-propanol?+?water and 2-propanol?+?water systems.  相似文献   
114.
Densities ‘ρ’, ultrasonic speeds of sound ‘u’ of binary mixtures of propiophenone (PPH) with aniline, N-Methylaniline, N,N-dimethylaniline and N,N-diethylaniline were measured over the entire composition range from 303.15 K to 318.15 K and at atmospheric pressure 0.1 MPa. Experimental data of ultrasonic sound were compared and discussed with the computed values of ‘u’ from various velocity theories like Nomoto’s relation (UNOM), impedance relation (UIMP), Van Dael and Vangeel’s ideal mix relation (UVDV), Rao’s specific velocity relation (URAO), Junjie’s theory (UJUN) and Jouyban-Acree’s (UJOE) relation for the above binary mixtures over the entire mole fraction range at the studied temperatures. The results are satisfactory and are in agreement between the theoretical and the experimental values. Further, the molecular interaction parameter (α), average percentage error and Chi-square test values were computed by using the values of experimental and theoretical ultrasonic velocities. The Δu values were correlated with Redlich-Kister polynomial equation to compute the coefficients and the standard deviations of the binary mixtures. The results were analyzed in terms of intermolecular interactions.  相似文献   
115.

In a wireless sensor network, wireless Energy transfer is a demanding technology for the energy difficulties in recent times. The foremost disadvantage of presentation is limited duration because WSN contains only restricted battery energy at a node. Therefore, we anticipated cluster-related wireless energy transfer in this document. The foremost intention of the method is to augment the duration of the sensor network through charging by the help of this wireless power transfer technology. So that, mobile charging vehicle (MCV) is established to move within the network and charge the sensor node battery wireless. The sensor nodes in the network are collected as a cluster for energy efficiency. Here, the cluster head is chosen for each one cluster in the network which is based on the rank metric value. Suppose, if one node in the network is reducing its energy, then the CH will send charge request and route ID to the MCV. Afterward, the MCV recognize the node by means of the exacting route and establish to charge the node. The reproduction consequences illustrate that the network lifetime of our anticipated method is enhanced than obtainable method.

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116.
Wireless Personal Communications - In this study, a coplanar waveguide fed patch antenna is proposed for Wireless Local Area Network (WLAN) and Worldwide Interoperability for Microwave Access...  相似文献   
117.
Wireless Personal Communications - Over the past decades Machine Learning and Deep Learning algorithm played a vital part in the development of Autonomous Vehicle. It is indeed for the perception...  相似文献   
118.
Features selection is the process of choosing the relevant subset of features from the high-dimensional dataset to enhance the performance of the classifier. Much research has been carried out in the present world for the process of feature selection. Algorithms such as Naïve Bayes (NB), decision tree, and genetic algorithm are applied to the high-dimensional dataset to select the relevant features and also to increase the computational speed. The proposed model presents a solution for selection of features using ensemble classifier algorithms. The proposed algorithm is the combination of minimum redundancy and maximum relevance (mRMR) and forest optimization algorithm (FOA). Ensemble-based algorithms such as support vector machine (SVM), K-nearest neighbor (KNN), and NB is further used to enhance the performance of the classifier algorithm. The mRMR-FOA is used to select the relevant features from the various datasets and 21% to 24% improvement is recorded in the feature selection. The ensemble classifier algorithms further improves the performance of the algorithm and provides accuracy of 96%.  相似文献   
119.
We have measured Seebeck coefficient (S) of FeTe0.5Se0.5 superconducting sample from 10 to 300 K. The variation of Seebeck coefficient with temperature of this system was found to be very anomalous, and the overall experimental observation of the S(T) was studied in the outline of a narrow-band model. In high-temperature region, the Seebeck coefficient is almost independent of temperature. Further, from the study of high-temperature magnitude of S, sample undergoes a change in sign in the Seebeck coefficient, wherein, appearance of a negative peak around 22 K and subsequently, its Seebeck coefficient goes to zero in the superconducting transition temperature regime around 11 to 13 K. It is revealed that the bandwidth and a small asymmetry involved in narrow bands give a realistic explanation to the anomalous temperature dependence of Seebeck coefficient of FeTe0.5Se0.5 system.  相似文献   
120.
Wireless Personal Communications - Network lifetime of mobile ad hoc networks is limited by the battery power of the mobile nodes. Energy saving can be achieved by operating the nodes in power save...  相似文献   
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