A Mid-infrared Study of Directly Imaged Planetary-mass Companions Using Archival Spitzer/IRAC Images

The atmospheres and accretion disks of planetary-mass and substellar companions provide an unprecedented look into planet and moon formation processes, most notably the frequency and lifetime of circumplanetary disks. In our ongoing effort to leverage the extraordinary sensitivity of the Spitzer/Infrared Array Camera (IRAC) at 3.6, 4.5, 5.8, and 8.0 μm to study wide planetary-mass and substellar companions near the diffraction limit, we present point-spread function fitting photometry of archival Spitzer/IRAC images for nine stars (G0 to M4+M7) in nearby star-forming regions or stellar associations that host companions at separations of ρ = 1.″17–12.″33. We detect all system primaries in all four IRAC channels and recover eight low-mass companions in at least one IRAC channel for our sample, five of which have not been resolved previously in IRAC images. We measure nonphotospheric [3.6]–[8.0] colors for four of the system companions (DH Tau B, 2M0441 B, SR 12 c, and ROXs 42B b), confirming or discovering the presence of circumstellar or circum(sub)stellar disks. We detect fluxes consistent with photospheric emission for four other companions (AB Pic b, CHXR 73 b, 1RXS J1609 b, and HD 203030 b) that are unlikely to host disks. Combined with past detections of accretion or disk indicators, we determine the global disk frequency of young (<15 Myr) wide companions with masses near the deuterium-burning limit to be 56% ± 12%.

Spectroscopic Fourier Transform Infrared Study of Poly (N-Isopropylacrylamide)-Human Recombinant Platelet-Derived Growth Factor- BB Protein as a Strategic Biobetter Regenerative Material

Biobetter or Biosuperior are recombinant protein drugs with one or more characteristics that are better than the original formulation. Platelet-Derived Growth Factor (PDGF) is a potent mitogen that can induce pulp stem cell proliferation and promote angiogenesis in vitro. PDGF-BB is required for wound healing, and they are chemoattractants that can activate macrophages and fibroblast activation in vitro. Poly(n-isopropylacrylamide) (PNIPAM) polymer is a thermoresponsive polymer widely used for drug delivery. A lyophilized combination of PNIPAM and 5µg of Recombinant Human PDGF-BB(rhPDGF-BB)(sigma Aldrich-P3201) protein was prepared in the present study. This combination was subjected to Spectroscopic Fourier-Transform Infrared(FTIR) study. The results suggested that a biophysical approach like FTIR enables assessing protein stability and aggregation tendency of recombinant proteins, contributing as a useful method to identify samples with prospective high therapeutic values.

Studies on Sodium lauryl sulphate supported Thorium(IV) phosphate: A New Surfactant supported Cation exchange resin, Useful in Water Purification

Background: With increasing population and decreased quality of drinking water, there is a great demand for the development of new materials and methods that can find applications in the purification of water. This paper presents our small effort from pollution to solution by presenting the synthesis method of new sodium lauryl sulphate supported thorium(IV) phosphate, its characterization, and disquisition of analytical applications by executing some dual separations of calcium. Methods: Sodium lauryl sulphate thorium(IV) phosphate was synthesized by sol gel method. The synthesized exchanger was characterized by some physico-chemical studies like powdered X-ray diffraction, Scanning electron microscopy, Thermo gravimetric-differential thermal analysis, EDAX and Fourier transform-infrared study and was also checked for its competency towards the ion exchange processes and in analytical chemistry. Results: The prominent characteristic of Sodium lauryl sulphate supported Thorium(IV) phosphate has been its tremendously high ion exchange capacity for sodium ions (3.10 meq/g) which is almost two and half times more than the exchange capacity of Thorium(IV) phosphate (ThP), i.e., 1.3 meq/g. The material was resulted in fibrous sheet which is quite thermally, mechanically stable and poorly crystalline. The material has shown selectivity towards Ca2+ and Hg2+ ions. Conclusion: The synthesized cation exchange material has been found quite thermally stable, showing drastically high exchange capacity and selectivity towards Hg2+ and Ca2+ metal ions which might be because of the use of an anionic surfactant, sodium lauryl sulphate while synthesis of Th(IV) phosphate which has played a key role in enhancing the exchange capacity and adsorption of specific metals as well. Therefore, based on the results obtained, the above said materials can find applications in water purification processes and also, in environmental pollution control where removal of Hg2+ and Ca2+ is required.

An In-Situ Transmission Fourier Transform Infrared Study on the Interaction Mechanism of Plasma with Nano-Catalyst for CO2 Methanation

The effects of discharge conditions and catalysts on CO2 methanation under the plasma were investigated via In-Situ transmission FTIR and OES analysis. The bare Al2O3, Ni/Al2O3 and Ru/Al2O3 catalysts were coated on the ZnSe window using the modified sol–gel method for In-Situ transmission FTIR analysis. It was confirmed from the OES analysis that the intensity of excited hydrogen increased in all catalysts as the discharge frequency and voltage increased, and the increment of H+ peak intensity was the largest in the Ru/Al2O3 catalyst. In addition, it was found from the In-Situ transmission FTIR analysis that the O-H band was all disappeared as the frequency and voltage increased. In conclusion, the increased H+ with the decomposition of O–H led to the increase in the CH4 conversion, resulting in the highest CH4 conversion in the Ru/Al2O3 catalyst.