RESUMO
The fluorescent colour in biodegradable and biocompatible flexible polymer nanocomposite gels was modulated in order to gain insight into the interfacial interactions of functional scaffolds with metal ions. The hybrid nanomaterials were introduced into the polymer matrix to obtain mechanically robust porous morphologies where the intrinsic luminescence matrix was found to critically enhance the threshold of the visual detection limits. The quenching of fluorescence intensity has been predominantly attributed to the interactions of functional receptors of luminescent nanofillers with respect to the chromophores of the fluorescent matrix. The chromium ion is selected to understand the change in fluorescence intensity of the nanocomposite gel with the degree of metal ion adsorption. The number of functional nanomaterials loaded into the matrix and the luminescence nature of the base polymer are varied with the purpose of gaining insight into the remote sensing mechanism of the colorimetric fluorescent probe.
RESUMO
There are several chemical methods for the synthesis of high energy-density fuel, exotetrahydrodicyclopentadiene (exo-THDCPD), however, still there is a challenge to synthesize exo-THDCPD conveniently. In present work, the exo-THDCPD from dicyclopentadiene (DCPD) has successfully synthesized through simplest and greener single step hydroconversion reaction over mesoporous supported nickel nanocatalyst (Ni/MCM-41). The reaction performed in autoclave under a hydrogen pressure ranging from 300-400 (Psi), temperature range 130-150 °C and progress has been monitored by gas chromatography which reveals that the reaction mechanism goes through dissociation-recombination of DCPD. The major reaction parameters such as temperature, pressure and nanocatalyst have been experimentally examined for the yield (85%) of the product. The structural analysis of exo-THDCPD is carried out by 1H NMR and FTIR techniques and the physicochemical properties have also been evaluated. Good quality nanocatalyst Ni/MCM-41 has been synthesized by impregnation incipient wetness method and characterized by XRD, EDAX, TEM, and BET techniques. The nanocatalyst is highly reactive due to its mesoporous structure having appropriate size and shape which gives free diffusion of the molecules. Repeatability of the nanocatalyst shows good reactivity up to the four runs.
RESUMO
Previous efforts to insert fullerenes into a carbon nanotube (CNT) involved the isolated synthesis of CNTs and fullerenes and then annealing CNTs and fullerenes together for encapsulation. We demonstrated the process for the continuous production of fullerene peapods inside the arc instrument by modifying the conventional arc ablation system, which can be repeated to obtain the desired mass scale product. Inside the arc discharge unit, by using the tunable external magnetic field, the double-walled CNTs (DWCNTs) were first synthesized and then directed to deposit onto the water cooled aluminium (Al) plate. The openings were created on DWCNTs by controlled heating of the Al plate and then fullerenes were synthesized and deposited on DWCNTs. In the arc instrument, fullerenes were finally directed to enter into DWCNTs from the defect sites by heating the Al plate in a vacuum. The formation of the peapod was established by the structure-property studies despite the huge deposition of metal catalyst nanoparticles and fullerenes on the surface of the nanotube which were a serious challenge for molecular level characterization of the grown peapod structures.
