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991.
K. Jacinth Mispa R. Muthulakshmi C. Prathees Kumar P. Subramaniam R. Murugesan 《Polymer-Plastics Technology and Engineering》2017,56(1):55-70
The synthesized polyaniline-Zr(IV) selenoiodate and polyaniline-Zr(IV) selenomolybdate composite ion exchangers were characterized by Fourier transform infrared spectroscopy, UV spectra, X-ray diffraction, scanning electron microscope, thermogravimetric analysis, and conductivity studies. The ion-exchange capacities, effect of eluent concentration, elution time, elution behavior, and pH on ion-exchange capacity were also studied to exploit the ion-exchange capability of the composites. The study revealed that polyaniline-Zr(IV) selenoiodate and polyaniline-Zr(IV) selenomolybdate ion exchangers are having excellent ion-exchange capacity values for K+ ion 1.36 and 1.44?meq?g?1, respectively. The organic polymeric part of the composites provides mechanical and chemical stability, whereas the inorganic part supports the ion-exchange behavior and thermal stability. The increase in electrical conductivity is due to the inorganic and organic parts. A mechanism for the formation of the polyaniline-Zr(IV) selenoiodate and polyaniline-Zr(IV) selenomolybdate composite ion exchangers is discussed, which may also be applied for the preparation of other composite ion exchangers. Sorption behavior of metal ions on the composites was studied in different solvent systems. On the basis of distribution coefficient values (Kd), it has been found that the cation-exchange materials are highly selective for Pb(II)-ions. Such modified composite materials can be applied as an electrochemically switchable ion exchanger for water treatment, especially water softening. 相似文献
992.
Sonalee Das Priyanka Pandey Smita Mohanty Sanjay Kumar Nayak 《Polymer-Plastics Technology and Engineering》2017,56(14):1556-1585
Castor oil has gained momentous attention as a valuable bio-based monomer and a potential alternative to the current petrobased polyol for synthesizing polyurethane due to the presence of inherent hydroxyl group. In spite of its huge potentiality very little has been reviewed regarding the development of polyurethane from castor oil. This review thus highlights the recent trends and development in the field of polyurethane and its nanocomposite based on castor oil including its biodegradability and weatherability studies. Further, this review also provides an insight regarding the utilization of castor oil based polyurethane and its nanocomposite for coating application. 相似文献
993.
Jayshri Kailas Madagul Durgesh Rameshlal Parakh Rachana S. Kumar Rakesh Ramesh Abhang 《Drying Technology》2017,35(12):1433-1449
The main objective of this study was to prepare a solid self-microemulsifying drug delivery system (S-SMEDDS) by spray drying liquid SMEDDS with an inert solid carrier Aerosil 200 to improve the dissolution rate and permeability of chlorthalidone (CTD). The liquid SMEDDS was composed of CTD, oleic acid, tween 20, and PEG 200. Preliminary screening was performed to select proper component combination. Solubility of CTD was determined in various vehicles. Ternary phase diagram for four series was constructed to delineate the boundaries of the nanoemulsion domain. Optimized S-SMEDDS (S3) was evaluated for dispersibility test (13.30?±?0.95), percentage transmittance (99.50?±?0.002), turbidity (260.43?±?1.02), percent drug content (97.86?±?0.56), droplet size (159.4), polydispersity index (PDI, 0.30), and zeta potential (?12.4). Solid-state characterization was done by scanning electron microscopy (SEM), differential scanning calorimetry, X-ray powder diffraction (XRD), and Fourier transform infrared (FT-IR). The XRD analysis confirmed that there was no crystalline CTD in the S-SMEDDS. SEM study revealed adsorption of liquid SMEDDS on Aerosil 200. In vitro drug release study was performed using water and 0.1N HCl as dissolution medium and compared with plain drug and marketed tablet Thaiklor TM 12.5, and marked increase in rate and extent of dissolution of S-SMEDDS was observed. Ex vivo intestinal permeability study revealed that diffusion of drug was significantly higher from S-SMEDDS than that of suspension of plain drug. The solid SMEDDS formulation was stable. In conclusion, the S-SMEDDS might be an encouraging strategy to improve the oral absorption of CTD. 相似文献
994.
Fumed SiO2 nanoparticle reinforced biopolymer blend nanocomposites with high dielectric constant and low dielectric loss for flexible organic electronics 下载免费PDF全文
Kalim Deshmukh M. Basheer Ahamed Kishor Kumar Sadasivuni Deepalekshmi Ponnamma Mariam Al‐Ali AlMaadeed Rajendra R. Deshmukh S. K. Khadheer Pasha Anji Reddy Polu K. Chidambaram 《应用聚合物科学杂志》2017,134(5)
In the present study, fumed silica (SiO2) nanoparticle reinforced poly(vinyl alcohol) (PVA) and poly(vinylpyrrolidone) (PVP) blend nanocomposite films were prepared via a simple solution‐blending technique. Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible spectroscopy (UV–vis), X‐ray diffraction (XRD), and scanning electron microscopy (SEM) were employed to elucidate the successful incorporation of SiO2 nanoparticles in the PVA/PVP blend matrix. A thermogravimetric analyzer was used to evaluate the thermal stability of the nanocomposites. The dielectric properties such as dielectric constant (?) and dielectric loss (tan δ) of the PVA/PVP/SiO2 nanocomposite films were evaluated in the broadband frequency range of 10?2 Hz to 20 MHz and for temperatures in the range 40–150 °C. The FTIR and UV–vis spectroscopy results implied the presence of hydrogen bonding interaction between SiO2 and the PVA/PVP blend matrix. The XRD and SEM results revealed that SiO2 nanoparticles were uniformly dispersed in the PVA/PVP blend matrix. The dielectric property analysis revealed that the dielectric constant values of the nanocomposites are higher than those of PVA/PVP blends. The maximum dielectric constant and the dielectric loss were 125 (10?2 Hz, 150 °C) and 1.1 (10?2 Hz, 70 °C), respectively, for PVA/PVP/SiO2 nanocomposites with 25 wt % SiO2 content. These results enable the preparation of dielectric nanocomposites using a facile solution‐casting method that exhibit the desirable dielectric performance for flexible organic electronics. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44427. 相似文献
995.
In the present study, we report a simple method to synthesize silver (Ag)‐polypyrrole (PPy)/graphene (Gr) nanocomposite as efficient electrode materials for supercapacitor application. The probable interaction between Ag nanoparticles with both PPy and Gr were characterized by FTIR, UV–visible, and Raman spectroscopies. The morphological analysis confirmed that the Gr sheets are uniformly coated by PPy and in the coated Gr sheets there is the presence of Ag nanoparticles. The Ag‐PPy/Gr nanocomposite achieved the highest specific capacitance of 472 F/g at a 0.5 A/g current density. Better energy and power density also obtained for the nanocomposite. The presence of both Ag nanoparticles and Gr is the main reason for the enhancement of the electrochemical properties of the nanocomposite. Based on the superior electrochemical properties, the nanocomposite can be used for next‐generation supercapacitor electrode material. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44724. 相似文献
996.
Effect of side‐chain functionality on the organic field‐effect transistor performance of oligo(p‐phenylenevinylene) derivatives 下载免费PDF全文
In order to observe the effects of the substitution of electronegative flourine with aromatic groups in oligo(p ‐phenylenevinylene) compounds on their packing, morphology, and charge carrier mobility, we have synthesized napthol‐substituted oligo(p ‐phenylenevinylene) compounds and examined their solubility, redox properties, thin film morphologies, and charge carrier properties. To date, very few examples of conjugated oligomers bearing napthol side groups have been reported in the literature. After annealing at 150 °C, the mobility of S1, S2, and S3 was 4.0 × 10?2 cm2 V?1 s?1, 1.2 × 10?2 cm2 V?1 s?1, and 2.6 × 10?3 cm2 V?1 s?1, respectively. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44825. 相似文献
997.
ENGAGE compatibilized HDPE/EPDM blends: Modification of some industrially pertinent properties and morphology upon incorporation of Mg(OH)2 filler and electron beam crosslinked network 下载免费PDF全文
Bhuwanesh Kumar Sharma Subhendu Ray Chowdhury Atanu Jha Amit Kumar Samanta Prakash Mahanwar Kuppa Sivasankara Sarma 《应用聚合物科学杂志》2017,134(23)
To observe the effect of ENGAGE (a poly‐olefin elastomer) on compatibilization of industrially important incompatible blend, high‐density polyethylene (HDPE)/ethylene‐propylene diene elastomer (EPDM), 15 wt % ENGAGE is incorporated into the system and the latter is found satisfactorily efficient as compatibilizer for the above system. To improve some industrially pertinent properties another strategies are also followed in addition, incorporation of magnesium hydroxide [Mg(OH)2] and electron beam (EB) crosslinking into the system. The gel content was found to increase with radiation dose, EPDM content and Mg(OH)2 dispersion. ENGAGE interestingly increases the gel content that is, promotes crosslinking. It is unique that filler dispersion and crosslinked network formation maintain the compatibility of the ternary system, which is confirmed by X‐ray diffraction, differential scanning calorimetry, mechanical properties, and scanning electron microscope. The compatibilization, Mg(OH)2 dispersion, and EB crosslinking improve the mechanical, thermo mechanical, flame retardant properties, and phase morphology considerably. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44922. 相似文献
998.
Amit Kumar Satyabrata Bhowmik Subhabrata Ray Gargi Das 《American Institute of Chemical Engineers》2017,63(2):792-800
The present report studies on the flow pattern transitions during vertical air water downflow through millichannels (0.83 ≤ Eötvös no. ≤ 20.63). Four basic flow patterns namely falling film flow, slug flow, bubbly flow, and annular flow are observed in the range of experimental conditions studied and their range of existence has been noted to vary with tube diameter and phase velocities. Based on experimental observations, phenomenological models are proposed to predict the transition boundaries between adjacent patterns. These have been validated with experimental flow pattern maps from the present experiments. Thus the study formalizes procedure for developing a generalized flow pattern map for gas‐liquid downflow in narrow tubes. © 2016 American Institute of Chemical Engineers AIChE J, 63: 792–800, 2017 相似文献
999.
Integration of biofuels intermediates production and nutrients recycling in the processing of a marine algae 总被引:1,自引:0,他引:1 下载免费PDF全文
Ali Teymouri Sandeep Kumar Elena Barbera Eleonora Sforza Alberto Bertucco Tomas Morosinotto 《American Institute of Chemical Engineers》2017,63(5):1494-1502
The cost‐effective production of liquid biofuels from microalgae is limited by several factors such as recovery of the lipid fractions as well as nutrients management. Flash hydrolysis, a rapid hydrothermal process, has been successfully applied to fractionate the microalgal biomass into solid biofuels intermediates while recovering a large amount of the nutrients in the aqueous phase (hydrolyzate) in a continuous flow reactor. The aim of the work is to enhance the quality of a high‐ash containing marine algae Nannochloropsis gaditana as biofuel feedstock while recycling nutrients directly for algae cultivation. Characterization of products demonstrated an increase in extractable lipids from 33.5 to 65.5 wt % (dry basis) while retaining the same fatty acid methyl ester profile, in addition to diminution of more than 70 wt % of ash compared to raw microalgae. Moreover, the hydrolyzate was directly used to grow a microalga of the same genus. © 2016 American Institute of Chemical Engineers AIChE J, 63: 1494–1502, 2017 相似文献
1000.
Characterizations of surfactant synthesized from Jatropha oil and its application in enhanced oil recovery 下载免费PDF全文
Surfactants are frequently used in chemical enhanced oil recovery (EOR) as it reduces the interfacial tension (IFT) to an ultra‐low value and also alter the wettability of oil‐wet rock, which are important mechanisms for EOR. However, most of the commercial surfactants used in chemical EOR are very expensive. In view of that an attempt has been made to synthesis an anionic surfactant from non‐edible Jatropha oil for its application in EOR. Synthesized surfactant was characterized by FTIR, NMR, dynamic light scattering, thermogravimeter analyser, FESEM, and EDX analysis. Thermal degradability study of the surfactant shows no significant loss till the conventional reservoir temperature. The ability of the surfactant for its use in chemical EOR has been tested by measuring its physicochemical properties, viz., reduction of surface tension, IFT and wettability alteration. The surfactant solution shows a surface tension value of 31.6 mN/m at its critical micelle concentration (CMC). An ultra‐low IFT of 0.0917 mN/m is obtained at CMC of surfactant solution, which is further reduced to 0.00108 mN/m at optimum salinity. The synthesized surfactant alters the oil‐wet quartz surface to water‐wet which favors enhanced recovery of oil. Flooding experiments were conducted with surfactant slugs with different concentrations. Encouraging results with additional recovery more than 25% of original oil in place above the conventional water flooding have been observed. © 2017 American Institute of Chemical Engineers AIChE J, 63: 2731–2741, 2017 相似文献