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161.
162.
This study evaluates environmental aggressiveness and atmospheric galvanic corrosivity categories in Chile (Classification of Industrial and Marine ATmospheres test) by installing bolts in electrical transmission towers in the Valparaiso region across four exposure sites: Playa Ancha, San Sebastián, Las Vegas, and San Felipe. Classifications of marine corrosion index (MCI), industrial corrosion index (ICI), and atmospheric corrosion index (ACI) used different galvanic couples: aluminum/steel for MCI, aluminum/copper for ICI, and aluminum/polyethylene for ACI. Corrosion indices varied by season (summer, autumn, winter, and spring), for which couples were exchanged every 3 months. Intraseason variation depended mainly on the meteorochemical variables of the zone, the Cl−/SO2 ratio, and the presence of general and pitting corrosion in the aluminum. The results indicate that, regardless of environmental condition, the aluminum in Al/steel (MCI) and Al/copper (ICI) couples presented a higher corrosion rate than when not forming a galvanic couple (ACI). Moreover, under higher environmental chloride, these differences increase. The Playa Ancha station presented the highest ACI. 相似文献
163.
Daniel K. Y. Solaiman Richard D. Ashby Alberto Nuñez Nicole Crocker 《Journal of surfactants and detergents》2020,23(3):553-563
Pseudohyphozyma (formerly Rhodotorula) bogoriensis synthesizes long-chain-length (22-carbon chain) sophorolipids (22:0-SL) that are variously acetylated at the 6′- or/and 6″-carbons of the sophorose unit. In this paper, we describe a low-temperature crystallization protocol that preferentially separates the 6′-monoacetylated 22:0-SL (6′-Ac1-22:0-SL) from a parental mixture of 22:0-SL containing a majority (64.7%) of the 6′,6″-diacetylated moiety (6′,6″-Ac2-22:0-SL), as deduced from high-pressure-liquid-chromatography evaporative-light-scattering-detection (HPLC-ELSD) and LC/Q-TOF-MS analyses. Tensiometry measurements using the Wilhelmy plate method yielded minimum-surface-tension (SFTmin) and critical-micelle-concentration (CMC) values of 34.6 ± 1.0 mN m−1 and 0.014 mM, respectively, for 6′-Ac1-22:0-SL (CRYSTAL) fraction and 34.9 ± 1.0 mM m−1 (SFTmin) and 0.018 (CMC) for the hexane precipitate (Hx-PRCP) fraction containing a high concentration (89.2%) of the diacetylated 6′,6″-Ac2-22:0-SL after crystal removal. In contrast, the SFTmin and CMC of the well-studied 16-18 carbon (C16-18)-SL of Starmerella bombicola were 35–37.2 mN m−1 and 0.05-(>0.3) mM, respectively. Individually, the purified CRYSTAL and Hx-PRCP fractions exhibited a similar degree of strong growth-inhibition activity against Cutibacterium (formerly Propionibacterium) acnes as determined by an agar-plate zone of inhibition assay. Study on the growth inhibition of oral health-related bacteria, i.e., Streptococcus mutans and Lactobacillus acidophilus, showed that, depending on the bacteria and strains tested, the CRYSTAL fraction was either slightly better than or equally effective as the Hx-PRCP fraction in inhibiting cell growth. 相似文献
164.
165.
Coleman Thomas F. Dumont Nicole S. Li Wanqi Liu Wenbin Rubtsov Alexey 《Computational Economics》2022,60(3):1101-1134
Computational Economics - The climate change model of Daniel et al. (Proc Natl Acad Sci USA 116(42):20886-20891, 2019. https://doi.org/10.1073/pnas.1817444116) is an important contribution to the... 相似文献
166.
167.
Engineering of strongly exothermic heterogeneously catalyzed reactions to industrial size is challenging. Synthesis of methanol and direct dimethyl ether synthesis serve as example for such type of reactions and related experimental results are described. Results from laboratory as well as technical scale are provided. The experiments show the variation of two main operational parameters: reaction temperature and CO2 content at reactor inlet. 相似文献
168.
Schuessler Benjamin J. Field David P. Overman Nicole R. Joshi Vineet V. 《Metallurgical and Materials Transactions A》2021,52(9):3871-3879
Metallurgical and Materials Transactions A - Uranium alloyed with 10 wt pct Mo (U-10Mo) undergoes discontinuous precipitation (DP) when subjected to sub-eutectoid heat treatment. It is hypothesized... 相似文献
169.
170.
cAMP pathway in podocytes 总被引:1,自引:0,他引:1
Podocytes possess receptors for a variety of hormones. The following receptors whose stimulation results in increased cAMP levels have been detected in podocytes: adrenergic beta(2) receptor, dopamine D(1) receptor, prostaglandin IP and EP(4) receptors, and parathyroid hormone (PTH)/PTH-related protein (PTHrP) receptor. Besides activating protein kinase A, increased levels of cAMP depolarize podocytes via opening of chloride channels. Relatively little is known about the impact of the cAMP pathway on podocyte function. Results obtained in a limited number of studies indicate that cAMP in podocytes may regulate cell morphology, actin assembly, and matrix production. In addition, cAMP seems to attenuate the action of hormones, which activate the Ca(2+)/protein kinase C pathway. Effects of the cAMP pathway on further aspects of podocyte biology, such as contractility, phosphorylation state of slit membrane-associated proteins, glomerular permeability, cell cycle control, and synthesis of reactive oxygen species can be anticipated from studies on other cell types and from studies on isolated glomeruli. In summary, the data available indicate that the cAMP pathway affects several aspects of podocyte biology in an overall glomerulo-protective manner. 相似文献