Ionic liquid mediated nano-composite polymer gel electrolyte for rechargeable battery application

ABSTRACT

Nano-composite polymer gel electrolytes (NPGEs) based on polymer poly(vinylidene fluoride-co-hexafluoropropylene) PVdF-HFP, ionic liquid, 1-butyl-3- methylimidazolium bis(trifluoromethanesulfonyl)imide BMIMTFSI, Li-salt along with the addition of SiO₂ nanoparticles have been synthesized and characterized by various techniques. Prepared NPGEs show high room temperature ionic conductivity (~10^?3 S/cm) and have a wide electrochemical window (ECW) (~3.3–3.5 V). The galvanostatic charge/discharge profile was studied by sandwiching best performing NPGEs between a LiFePO₄ cathode and lithium metal anode. The specific discharge capacity of the cell (Li/NPGE/LiFePO₄) room temperature at 0.1C rate is found to be 138 mAh/g.     

Electrical,mechanical, structural,and thermal behaviors of polymeric gel electrolyte membranes of poly(vinylidene fluoride‐co‐hexafluoropropylene) with the ionic liquid 1‐butyl‐3‐methylimidazolium tetrafluoroborate plus lithium tetrafluoroborate

Polymeric gel electrolyte membranes based on the polymer poly(vinylidene fluoride‐co‐hexafluoropropylene) [P(VdF–HFP)] with different weight percentages of the ionic liquid (IL) 1‐butyl‐3‐methylimidazolium tetrafluoroborate plus 0.3M lithium tetrafluoroborate (LiBF₄) salt were prepared and characterized by scanning electron microscopy, X‐ray diffraction, differential scanning calorimetry, thermogravimetric analysis, Fourier transform infrared (FTIR) spectroscopy, complex impedance spectroscopy, pulse echo techniques, and Vickers hardness (H) testing. After the incorporation of the IL plus the salt solution in the P(VdF–HFP) polymer, the melting temperature, glass‐transition temperature (T_g), degree of crystallinity, thermal stability, elastic modulus (E), and hardness (H) gradually decreased with increasing content of the IL–salt solution as a result of complexation between the P(VdF–HFP) and IL. This was confirmed by FTIR spectroscopy. A part of the IL and LiBF₄ were found to remain uncomplexed as well. The ionic conductivity (σ) of the polymeric gel membranes was found to increase with increasing concentration of the IL–salt solution. The temperature‐dependent σs of these polymeric gel membranes followed an Arrhenius‐type thermally activated behavior. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41456.     

Synthesis and characterization of new hyperbranched poly(ether ketones) with various number of phenylene units

A new series of AB₂ type monomers with aromatic thio and various number of phenylene units were prepared. Three series of AB₂ type monomers, 4-thio-3′,5′-bis(4-fluorobenzal)biphenyl 1, 4-thio-3′′,5′′-bis(4-fluorobenzal)-p-terphenyl 2 and 4-thio-3′′′,5′′′-bis(4-fluorobenzal)-p-quarterphenyl 3 were synthesized in a stepwise manner starting from 3,5-bis(4-fluorobenzoyl)phenol 4 by repeating a series of conversions of the hydroxy group to the triflate, cross-coupling reaction of the triflate with (p-methoxythiophenyl)boronic acid, reduction of carbonyl groups followed by conversion of methylthio to thio group. Three kinds of hyperbranched poly(ether ketones) were prepared by the polymerization of the these three AB₂ type monomers. All compounds were characterized by elemental analysis, thermal analysis, ¹H and ¹³C NMR spectrometry.     

Thiol‐mediated degradation of DNA adsorbed on a colloidal gold surface

When [³²P]‐labeled DNA is adsorbed on colloidal gold from a 130 mmol dm^?3 solution of KH₂PO₄, it can subsequently be eluted with cold DNA without undergoing detectable degradation. Similarly, DNA can be incubated in solution in the presence or absence of colloidal gold with high concentrations of β‐mercaptoethanol or hexane‐1‐thiol without significant degradation. However, when adsorbed DNA is eluted from gold with solutions of one of the thiols, it is recovered as a mixture of mononucleotides and short oligomers. The extent of degradation increases with increasing concentration of the thiol and with increasing elution temperature. Our results emphasize that in designing protocols involving DNA adsorbed on gold surfaces, it is important to avoid allowing the DNA to come into contact with even moderate concentrations of thiols. © 2003 Society of Chemical Industry     

麻疯树果壳活性炭处理活性艳红B-3BF废水

采用微波-磷酸法活化麻疯树果壳制备活性炭,选取活化制备的性能最优活性炭与废水反应,其对模拟废水的吸附在90min后趋于稳定,色度去除率为91％。处理模拟印染废水的最佳投加量为400mg／100mL。废水pH值在4或10左右均可以获得较好去除效果。对模拟印染废水的吸附行为符合Freundlich和Langmuir吸附等温方程。以微孔为主的商业活性炭对模拟印染废水的去除效果较差,而孔径在1-10nm之间最为丰富的麻疯树果壳活性炭去除效果达90％以上。     

Development and characterization of liquid carbon fibre reinforced aluminium matrix composite

The progress and developments in materials technology have resulted in several new materials like metal–matrix composites (MMCs). On account of excellent physical, mechanical and development properties, MMCs are applied widely in aircraft and automobile technology. The present paper deals with the development of aluminium matrix composite reinforced with carbon preform having a volume fraction of 20–25% using squeeze casting infiltration process. Hardness, impact and tension test on the squeeze cast matrix and the composite was conducted to study the improvement in properties compare to that of matrix. Even though ultimate tensile strength of composite is found to be decreased, an increased Brinell hardness number and a four-fold improvement in toughness are noticed. Characterization of the materials done using optical and scanning electron microscope (SEM) revealed that the carbon fibers are evenly distributed in the matrix and the alloy is appeared to have smaller dendrite size. The lack of observed fibre pull-out on fracture and improved mechanical properties resulted due to the good wetting of the fibers by the liquid alloy.     

Effect of Chitosan Gallate Coating on the Quality Maintenance of Refrigerated (4 °C) Silver Pomfret (<Emphasis Type="Italic">Pampus argentus</Emphasis>)

The effect of chitosan (CS)-gallic acid (GA) conjugate (chitosan gallate, CS-g-GA) coating on the quality of silvery pomfret (Pampus argenteus) during refrigerated storage at 4 °C for 15 days was investigated. The total mesophilic and psychrotrophic microbes in control and coated fish samples were counted periodically; physicochemical analyses to determine pH, total volatile basic nitrogen (TVB-N), peroxide value (POV), thiobarbituric acid-reactive substances (TBARS), K-value, and water-holding capacity (WHC) were carried out; and sensory attributes were evaluated. The results indicated that both CS + GA and CS-g-GA coatings effectively preserved the silvery pomfret quality during refrigerated storage. However, CS-g-GA had higher antimicrobial activity and a better ability to inhibit the formation of volatile bases (TVB-N) and lipid oxidation products (POV and TBARS) as well as the degradation of ATP and its breakdown products (K value) than CS + GA during the storage period. Furthermore, the CS-g-GA coating also helped to maintain a higher WHC and had better sensory properties for a longer period of time compared to the other treated samples, thus extending the shelf life and delaying the deterioration of fresh silvery pomfret by 3–6 days during refrigerated storage. These results suggest that a CS-g-GA coating could be employed as an active packaging material in the fish preservation industry.     

Emerging Molecular Connections between NM23 Proteins,Telomeres and Telomere-Associated Factors: Implications in Cancer Metastasis and Ageing

The metastasis suppressor function of NM23 proteins is widely understood. Multiple enzymatic activities of NM23 proteins have also been identified. However, relatively less known interesting aspects are being revealed from recent developments that corroborate the telomeric interactions of NM23 proteins. Telomeres are known to regulate essential physiological events such as metastasis, ageing, and cellular differentiation via inter-connected signalling pathways. Here, we review the literature on the association of NM23 proteins with telomeres or telomere-related factors, and discuss the potential implications of emerging telomeric functions of NM23 proteins. Further understanding of these aspects might be instrumental in better understanding the metastasis suppressor functions of NM23 proteins.