This paper characterizes the actual science performance of the James Webb Space Telescope (JWST), as determined from the six month commissioning period. We summarize the performance of the spacecraft, telescope, science instruments, and ground system, with an emphasis on differences from pre-launch expectations. Commissioning has made clear that JWST is fully capable of achieving the discoveries for which it was built. Moreover, almost across the board, the science performance of JWST is better than expected; in most cases, JWST will go deeper faster than expected. The telescope and instrument suite have demonstrated the sensitivity, stability, image quality, and spectral range that are necessary to transform our understanding of the cosmos through observations spanning from near-earth asteroids to the most distant galaxies.

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In this work, we synthesized polyimides by incorporating an aromatic diamine monomer with a methylene linker, 4,4'‐methylenebis(2,6‐dimethylaniline) (MBDMA), to make a robust main chain along with aliphatic polyetherdiamine backbone linkers to reduce rigidity. We designed the polymers to exhibit thermal properties in between those of conventional aromatic polyimides and polymers with wholly aliphatic ether diamine links. Through dynamic mechanical analysis and differential scanning calorimetry, it is shown that control of the molar ratios of the aromatic MBDMA (4,4'‐methylenebis(2,6‐dimethylaniline)) and the composition and size of the aliphatic polyetherdiamine can be used to tune the glass transition. The polymers were characterized by GPC, FTIR, NMR, thermomechanical and calorimetric analysis, and microhardness testing. POLYM. ENG. SCI., 59:221–232, 2019. © 2018 Society of Plastics Engineers

-This work deals with the development of a digital image analysis procedure to characterize microbial flocs obtained in three different WWTP: a bench-scale Sequencing Batch Reactor (SBR) dealing with phenol and nitrogen biological removal, a municipal treatment unit (Ilha do Governador, Rio de Janeiro, Brazil) and an industrial wastewater treatment plant (Ciba -Estrada do Colégio, Rio de Janeiro, Brazil). The developed procedure permits to obtain its morphological parameters like equivalent diameter, compactness, roundness and porosity properties as well as the fractal dimension. This procedure was validated and lead to identify the major relationships between the analysed morphological parameters. A minimum of 300 flocs should be included in the image analysis and a significant influence of the sample dilution step on the mean size of the flocs was verified. The porosity parameter positively correlated with the fractal dimension of microbial aggregates indicating the that highly porous flocs are very irregular.

Recently, we have studied polyimides (PIs) synthesized by incorporating an aromatic diamine monomer with a methylene linker, 4,4 0 -methylenebis(2,6-dimethylaniline), to make a robust main chain along with aliphatic polyetherdiamine backbone linkers to reduce rigidity. In this report, we incorporate a urea linkage into these materials in order to observe the effect of additional hydrogen bonding. The polymers are designed to exhibit thermal properties in between those of conventional aromatic PIs and polymers with wholly aliphatic ether diamine links. Herein, we demonstrate that the addition of 1,6 hexamethylene diisocyanate and the increase of hydrogen bonds at the urea linkage can be used to improve the thermal and mechanical properties of the PI. Furthermore, the imide ring is an important component to maintain the thermal stability characteristics in polyimidepolyurea hybrids. The polymers were characterized by FTIR, thermomechanical and calorimetric analysis, microhardness, and tensile testing.