Distributions of branched glycerol dialkyl glycerol tetraethers (brGDGTs) from soil bacteria have been recently used for reconstructions of past soil pH and air temperature history. Here, we report the brGDGTs distribution patterns from different climate regions of China, using 42 novel brGDGT data from sub-tropical Chinese soils, compiled alongside previously-published data encompassing different environmental conditions across China. These patterns show high abundance of Ia fraction in soils from humid areas, and high abundance of IIa' and IIIa' fractions corresponds to semi-humid or semi-arid conditions, implying a possible relationship with precipitation. The abundance of IIa fraction appears negatively correlated with air temperature. Statistically, the soil pH and temperature factors represent 62% and 30% variations of the total variance respectively. For soils from humid and semi-humid regions, strong correlations between cyclization of branched tetraethers (CBT') index and soil pH (R = 0.89) and between methylation of branched tetraethers (MBT') index and mean annual temperature (MAT)(R = 0.82) exist. When soils from semi-arid regions are included, the correlations become slightly stronger with pH and significantly weaker with MAT. Our study confirms the usefulness of soil brGDGTs distributions for Quaternary palaeo-climate reconstructions.
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http://dx.doi.org/10.1038/s41598-019-39147-9 | DOI Listing |
Molecules
January 2025
N. S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninsky Prosp. 31, 119991 Moscow, Russia.
The interaction of sodium phytate hydrate CHOP·xNa·yHO (phytNa) with Cu(OAc)·HO and 1,10-phenanthroline (phen) led to the anionic tetranuclear complex [Cu(HO)(phen)(phyt)]·2Na·2NH·32HO (), the structure of the latter was determined by X-ray diffraction analysis. The phytate is completely deprotonated; six phosphate fragments (with atoms P1-P6) are characterized by different spatial arrangements relative to the cyclohexane ring (1a5e conformation), which determines two different types of coordination to the complexing agents-P1 and P3, P4, and P6 have monodentate, while P2 and P5 are bidentately bound to Cu cations. The molecular structure of the anion complex is stabilized by a set of strong intramolecular hydrogen bonds involving coordinated water molecules.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Academy for Engineering and Technology, Yiwu Research Institute, Zhuhai Fudan Innovation Institute, Fudan University, Shanghai 200433, China.
While the traditional rubber industry faces the severe pressure of environmental pollution and carbon emissions, bio-based and biodegradable elastomers have become a hot topic in the field and drawn intensive research interest. Inspired by polyester resin, incorporating polyol or polycarboxylic acid as a branching unit into aliphatic polyester and/or introducing a monomer with a C=C bond to provide open-bond cross-linking in the fashion of common vulcanization to form three-dimensional network structures are two mainstream strategies for designing biodegradable polyester elastomers (BPEs). Both methods encounter more or fewer problems, such as poor mechanical and thermal properties due to the easy hydrolysis of the ester bond and space hinderance, or the potential harm of the remaining degraded small molecules with olefin bonds.
View Article and Find Full Text PDFFoods
January 2025
Heyuan Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Heyuan 517000, China.
This study investigated the impact of glycerol monooleate (MO) at varying levels (0.3%, 0.6%, 0.
View Article and Find Full Text PDFMacromol Rapid Commun
January 2025
Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, China.
Hexaarylbiimidazole (HABI) molecules have awakened a broad interest in photo-processing, super-resolution imaging, photoinduced self-healing materials, and photomechanical hydrogels due to their excellent photosensitivity and photo-induced cleavage properties. In this work, a novel photoswitchable branched polyurethanes (BPU), which are synthesized by copolymerizing HABI with glycerol, isophorone diisocyanate (IPDI), and polyethylene glycol (PEG), is designed. 7-Diethylamino-4-methylcoumarin (DMCO) is introduced as a radical quencher, which can not only avoid the hydroxyl interfering from conventional radical scavengers during the polymerization process but also promote efficient quenching of TPIR radicals.
View Article and Find Full Text PDFChemistry
January 2025
School of Chemistry and Chemical Engineering, Lingnan Normal University, 524048, Zhanjiang, China.
The development of Pd-based bimetallic nanoalloys (NAs) with abundant active sites for achieving highly efficient electrocatalysis in alcohol oxidation deserves continuous attention. Herein, we utilized a facile visible-light-assisted liquid-phase method involving adjusting reaction time to generate active sites, successfully synthesizing one-dimensional (1D) PdAg NAs rich in defects. The optimized 1D PdAg NA exhibits remarkable electrochemical activity, stability, and antipoisonous properties in glycerol oxidation reaction (GOR) and ethanol oxidation reaction (EOR), far exceeding pure Pd and commercial Pd/C catalysts.
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