Hydrogen is emerging as a promising zero-carbon emission energy source for vehicle engines. However, the full potential of hydrogen engines and their economic viability remain uncertain. Additionally, comprehensive data on ultralean combustion performance and emissions as well as strategies for improving HC and CO emissions are lacking.
View Article and Find Full Text PDFA series of novel and modular ferrorence-based amino-phosphine-binol (f-amphbinol) ligands have been successfully synthesized. The f-amphbinol ligands exhibited extremely high air stability and catalytic efficiency in the Ir-catalyzed stereoselective hydrogenation of various ketones to afford corresponding stereodefined alcohols with excellent results (full conversions, cis/trans >99:1, and 83% → 99% ee, TON up to 500 000). Control experiments have shown that -OH and -NH groups played a key role in this stereoselective hydrogenation.
View Article and Find Full Text PDFObjective: The burden of both general and drug-resistant tuberculosis in rural areas is higher than that in urban areas in China. To characterize the genetic structure and transmission risk of in rural China, we used whole genome sequencing to analyze clinical strains collected from patients in two counties of Yichang for three consecutive years.
Methods: From 2018 to 2020, sputum samples were collected for cultures from patients with suspected tuberculosis in Yidu and Zigui county, and DNA was extracted from the positive strains for genome sequencing.
Bioorg Med Chem Lett
November 2021
Vidarabine (ARA) was one of the earliest marine-related compounds to be used clinically for antiviral therapy, however, its fast metabolism is the main defect of this drug. To overcome this, we designed and synthesized a group of phosphamide-modified ARA compounds using ProTide technology. With a phosphamide modification, these compounds could become the substrate of specific phospholipase enzymes expressed in the liver.
View Article and Find Full Text PDFSubstrate concentrations greatly influence bacterial growth and metabolism. However, optimal nitrogen concentrations for anammox bacteria in nitrogen-limited environments remain unclear. Here, we observed enhanced nitrogen metabolism and anabolism of anammox bacteria at low nitrogen conditions.
View Article and Find Full Text PDFAlthough the niche differentiation of anammox bacteria has been extensively observed in a lab-scale reactor, the inherent mechanism for this ecological phenomenon is still elusive. Here, we combined the long-term reactor operation, genome-centered metagenome, and metatranscriptome analyses to gain insight into the substrate competition and niche differentiation of Candidatus Jettenia and Candidatus Brocadia. After 146 days of operation, we found the anammox bacterial population shifted from Ca.
View Article and Find Full Text PDFEnviron Sci Technol
August 2017
Substrate concentrations generally fluctuate in wastewaters. However, how anammox biomass behaves to overcome the stress of alternating feed loadings remains unclear. Here, we combined long-term reactor operation, batch tests, 16S rRNA transcript sequencing, and metabolomics analysis to investigate the aggregation of anammox biomass under the regulation of c-di-GMP, a key second messenger, in response to alternating feed loadings.
View Article and Find Full Text PDFIn this study, two times more serious membrane fouling was found in anammox membrane bioreactor, compared to partial nitrification membrane bioreactor (PN-MBR) operated at the same nitrogen loading rate. By protein, polysaccharide, amino acids and functional groups analysis, it was found that the discrepancy in membrane fouling was virtually due to the difference in microbial products of nitrifiers and anammox bacteria. Protein and polysaccharide were main foulants on membrane surface; meanwhile theirs content and ratio in the EPS, supernatant and membrane surface were significantly different in PN-MBR and anammox-MBR.
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