Notes

Micromachining of glassy carbon dioxide by using a Yb-based master oscillator energy amp nanosecond fiber laser beam.
Copyright © 2020 American Chemical Society.Gold nanoparticles are utilized in a variety of sensing and detection technologies because of their unique physiochemical properties. Their tunable size, shape, and surface charge enable them to be used in an array of platforms. The purpose of this study is to conduct a thorough spectroscopic characterization of Au and functionalized hybrid Au@SiO2 nanoparticles under physiological conditions and in the presence of two proteins known to be abundant in serum, bovine serum albumin and human ubiquitin. The information obtained from this study will enable us to develop design principles to synthesize an array of surface-enhanced Raman spectroscopy-based nanoparticles as platforms for theranostic applications. We are particularly interested in tailoring the surface chemistry of the Au@SiO2 nanoparticles for applications in theranostic technologies. We employ common spectroscopic techniques, with particular emphasis on circular dichroism and heteronuclear single quantum correlation nuclear magnetic resonance (HSQC NMR) spectroscopy, as combinatorial tools to understand protein conformational dynamics, binding site interactions, and protein corona for the design of nanoparticles capable of reaching their intended target in vivo. Our results conclude that protein adsorption onto the nanoparticle surface prevents nanoparticle aggregation. We observed that varying the ionic strength and type of ion influences the aggregation and aggregation rate of each respective nanoparticle. The conformation of proteins and the absorption of proteins on the surface of Au nanoparticles are also influenced by ionic strength. Using two-dimensional [15N-1H]-HSQC NMR experiments to compare the interactions of Au and Au@SiO2 nanoparticles with 15N-ubiquitin, we observed small chemical shift perturbations in some amino acid peaks and differences in binding site interactions with ubiquitin and respective nanoparticles. Copyright © 2020 American Chemical Society.The detailed investigation of the chemical structure of vitrinite-rich Karharbari coal was performed utilizing advanced analytical techniques. The salient objective of this work is the evaluation of various structural properties of coal, which is necessary for identifying the chemical and physical interactions between coal and various reactants during its utilization. Karharbari coal is a poorly organized coal with high aromatic content. The value of corrected aromaticity (f a') was found to be 0.82 by 13C NMR spectroscopy and was also confirmed by XRD (aromaticity = 0.84) and FT-IR analysis (aromaticity = 0.82). The average molecular weight of the aromatic cluster was found to be 507 amu by the NMR result, which is closer to the result obtained by HRTEM (MW = 530 amu). The structural and lattice parameters of Karharbari coal were obtained by NMR spectroscopy and then compared with the similar rank Argonne Premium coal. The molecular weight distribution was obtained by LD-TOF-MS and compared with HRTEM fringe model analysis. The presence of different heteroatoms like carbon, oxygen, nitrogen, and sulfur with their functionalities was determined by using the XPS technique. Different carbon/oxygen functionalities present in the Karharbari coal were found to be (C-C) and (C-H) 68.5%, (C-O) 23.4%, (COO-) 1.9%, and (C=O) 6.0%. Nitrogen functionalities such as pyridine, pyrrolic, quaternary, and oxidized nitrogen and their compositions (mol %) were 19.3, 45.6, 31.2, and 3.7%, respectively. Different forms of sulfur were also found to be present, namely, thiophenes, sulfones, sulfuric acid, and sulfates with the molar contents of 16.4, 41.6, 21.3, and 20.5%, respectively. This information will be useful in improvising coal utilization techniques. Copyright © 2020 American Chemical Society.Toxic solvents such as dimethylformamide (DMF) are widely used for the preparation of polymeric membranes due to the strong dissolving power. Environmentally friendly solvents are available, but the developed membranes suffered from low performance due to the poor solubility of the polymer in the solvent. In this work, polyetherimide membranes were prepared using DMF with the addition of the biodegradable solvent γ-butyrolactone (GBL). Results show that mixing 75 wt % of DMF with 25 wt % GBL enhanced the membrane gas permeability toward hydrogen, methane, helium, carbon dioxide, and nitrogen. The overall permeability was increased by 9.6% compared to the permeability of the membrane made by 100 wt % DMF. Hydrogen-to-methane selectivity was also raised from 26.3 to 29.3. Copyright © 2020 American Chemical Society.Surfactin, as one of the most powerful biosurfactants, can be widely applied in agriculture, food, and pharmaceutics. However, low biosynthesis efficiency is the major obstacle in its commercialization. Here, we used nanoparticles to increase the surfactin production in Bacillus amyloliquefaciens MT45 through enhancing the secretion (the key step of surfactin biosynthesis). The results showed that the surfactin titer increased from 4.93 to 7.15 g/L in the flask and from 5.94 to 9.18 g/L in a 7 L bioreactor by adding 5 g/L Fe nanoparticles. They were the highest titers in the reported wild-type strain. Our results indicated that Fe nanoparticles enhanced the expression of genes involved in the biosynthesis of surfactin. Moreover, Fe nanoparticles increased the permeability of cell membranes, resulting in a more efficient secretion of surfactin. This study provides an efficient strategy for increasing the biosynthesis of microbial metabolites and provides new insights into the nanoparticles' impacts on microbes. Copyright © 2020 American Chemical Society.This work seeks for a better understanding on how the gas treatment process affected the structure of metal loaded zeolite Y (MY, M = Ag, Cu) adsorbants and how the structural changes affected the performances of the adsorbents for adsorptive desulfurization. A series of characterization tools including solid-state nuclear magnetic resonance were employed. Compared to the N2 treatment, the H2 treatment on the MY adsorbents led to the reduction of the loaded M components to their metallic state and, consequently, brought several structural changes to the zeolitic framework. KYA1797K supplier The structural changes brought by the H2 treatment can be accounted for the decreased Brönsted acidity over the Lewis acidity of the adsorbents and thus helped in improving their adsorption capacity. This paper provides new insights on how the zeolitic framework changes affected the sulfur adsorption capacity of MY, which is helpful for designing better adsorbents for sulfur removal from oil. Copyright © 2020 American Chemical Society.
Here's my website: https://www.selleckchem.com/products/kya1797k.html