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Pd^(0)-O v-Ce^(3+) Interfacial Sites with Charge Redistribution for Enhanced Hydrogenation of Methyl Oleate to Methyl Stearate

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Transactions of Tianjin University 2024年第4期30卷 359-368页

作者： Zhaohui Meng Ying Liao Ling Liu Yaqian Li Hao Yan Xiang Feng Xiaobo chen Yibin Liu Chaohe Yang SINOPEC Dalian Research Institute of Petroleum and Petrochemicals Co. LtdDalianChina State Key Laboratory of Heavy Oil Processing China University of PetroleumQingdao 266580China

Improving the efficiency of metal/reducible metal oxide interfacial sites for hydrogenation reactions of unsaturated groups(e.g.,C=C and C=O)is a promising yet challenging *** our study,we developed a Pd/CeO_(2) catalyst by enhancing the oxygen vacancy(O V)concentration in CeO_(2) through high-temperature *** process led to the formation of an interface structure ideal for supporting the hydrogenation of methyl oleate to methyl *** cally,metal Pd^(0) atoms bonded to the O V in defective CeO_(2) formed Pd^(0)-O v-Ce^(3+)interfacial sites,enabling strong electron transfer from CeO_(2) to *** interfacial sites exhibit a synergistic adsorption eff ect on the reaction ***^(0) sites promote the adsorption and activation of C=C bonds,while O V preferably adsorbs C=O bonds,mitigating competition with C=C bonds for Pd^(0) adsorption *** synergy ensures rapid C=C bond activation and accelerates the attack of active H*species on the semi-hydrogenated *** a result,our Pd/CeO_(2)-500 catalyst,enriched with Pd^(0)-O v-Ce^(3+)interfacial sites,dem-onstrated excellent hydrogenation activity at just 30℃.The catalyst achieved a Cis-C18:1 conversion rate of 99.8% and a methyl stearate formation rate of 5.7 mol/(h·g metal).This work revealed the interfacial sites for enhanced hydrogenation reactions and provided ideas for designing highly active hydrogenation catalysts.

关键词： Hydrogenation Interfacial sites Oxygen vacancy C=C bond

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iTRAQ-based Quantitative Proteomic Profiling of the Regulatory Mechanisms on Immune Functions and Blood Lipids in Aged Mice Fed with Lentinula edodes-Derived Polysaccharides

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Food Science and Human Wellness 2024年

作者： Xiaofei Xu Xiaofei Liu Jin chen Jingjing Guan Donghui Luo College of Food Science and Engineering， Guangdong Ocean University

The mechanisms of mushroom polysaccharides on immune functions and lipid metabolism of aged mammals have not been fully elucidated. In the present study， after assessing the impacts of one type of Lentinula edodes-derived polysaccharides， named L2， on immune functions and blood lipid profiles， isobaric tags for relative and absolute quantification (iTRAQ)-based proteomic profiling of the small intestinal tissues from aged mice treated with L2 was performed. L2 reversed immune function declines and modulated the lipid metabolism of aged mice evidenced by increased levels of serum TC， HDL-C， and LDL-C， and reduced levels of serum TG. Moreover， a total of 95 differentially regulated proteins (DRPs) were identified， of which 75 were up-regulated and 20 were down-regulated. Most of the DRPs were involved in intracellular and extracellular structure organization， and cellular and metabolic regulation. Particularly， approximately 16 and 9 DRPs participated in the regulation of immune functions and lipid metabolism， respectively. Furthermore， protein-protein interaction analysis highlighted that cadherin 1， plectin， cadherin-17， Ras GTPase-activating-like protein IQGAP2， and ezrin might be key proteins in response to L2 treatment. These findings provide new insights into the biological mechanisms of mushroom polysaccharides in anti-aging from a proteomic perspective.

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Durable ruthenium oxide catalysts for water oxidation reaction

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Science China Chemistry 2024年

作者： Jixiang Jiao Ding chen Hongyu Zhao Ying Dong Shichun Mu State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology

Water electrolysis is an important way for high-purity hydrogen production. However, the oxygen evolution reaction（OER）, as a key reaction, has a high energy barrier, and the associated catalyst is prone to failure. Therefore, efficient and stable OER catalysts are urgently required. Compared with commercial iridium oxide（IrO2）, ruthenium oxide（RuO2） has a lower price and higher catalytic activity for OER due to its location at the near-top of the volcano plot, but has lower structural stability. Thus, an in-depth understanding of the failure mechanism of RuO2is conducive to the reaction pathway design and structural modulation for obtaining higher stable RuO2catalysts. Here, we discuss recent advances in the enhancement of the stability of RuO2catalysts. First, we analyze in depth the three failure modes of RuO2, including the oxidation of Ru, the lattice oxygen evolution,and the catalyst exfoliation during the OER process. Second, to improve the durability of RuO2catalysts, five modification strategies, comprising defective engineering, strain engineering, phase engineering, interface engineering and microenvironmental engineering, are summarized, and corresponding enhancement mechanisms are also discussed. Finally, the challenges and possible solutions for further breakthroughs of RuO2catalysts are proposed, and the future research trends and prospects of RuO2catalysts are also envisioned. Undoubtedly, this work will contribute to the understanding and design of highly stable OER catalysts and beyond.

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MOF-assisted Synthesis of Dual-atom Palladium Catalysts for Acetylene Semi-hydrogenation

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China Petroleum Processing & Petrochemical Technology 2024年第3期26卷 42-52页

作者： chen Jie Xu Yuebing Qi Jian Liu Bing Liu Xiaohao Department of Chemical Engineering School of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

The selective removal of trace acetylene in ethylene feed gas is of great significance in the petrochemicalindustry;however, there are still challenges in designing and developing high-performance catalysts. Here, a MOFassistedencapsulation strategy was adopted for the precise synthesis of diatomic Pd2 sites on a ZnO support. When usedfor the acetylene semi-hydrogenation reaction, the dual-atom Pd2-ZnO catalyst exhibited improved catalytic performance,achieving complete conversion of acetylene at 125 °C with an 89% selectivity to ethene, as compared to Pd single-atom andnanoparticles. This enhancement was mainly attributed to the catalyst’s ability to dissociate H2 and facilitate the desorptionof intermediate C2H4. Moreover, the strong interaction between the support and the diatomic Pd sites was responsible for thecatalyst’s excellent stability during the long-term reaction.

关键词： dual-atom palladium acetylene semi-hydrogenation MOFs hydrogen dissociation intermediate

Resonance Analysis in a High-Rise Building: Combined Translational and Rotational Measurements

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Journal of Earth Science 2024年第3期35卷 1069-1074页

作者： Linpeng Qin Yun Wang Chang chen Yongxiang Wei Chunqi Liao Yi Zhang Chao Wang Wentao Wan Quanyang Shao School of Geophysics and Information Technology China University of GeosciencesBeijing 100083China Fujian Earthquake Agency Fuzhou 350003China Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081China

0 INTRODUCTION Resonance frequency is an important indicator for structure health monitoring,which can be exacerbated by various natural forces,such as rainfall,earthquakes,and hurricanes(Wu et al.,2021;Shan et al.,2020;Gentile et al.,2016;Moser and Moaveni,2011).Clinton et al.(2006)found that changes in environmental factors could significantly affect the resonance frequency of the Millikan Library;and that compared with temperature,humidity and strong wind have greater impacts on resonance ***,some studies have confirmed the effects of environmental factors through mathematical statistical analyses,including Xia et al.(2006),Yuen and Kuok(2010),and Guéguen et al.(2017).Other studies(e.g.,Astorga et al.,2018)revealed a building’s self-healing ability,where the building’s resonance frequency drifts due to earthquake events,environmental factors,or random forced vibrations could gradually return to its original level,but the recovery time of frequency drift could be considerably different with respect to different environmental factors.

关键词： humidity rainfall earthquake

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Stability and variability of molecular subtypes: comparative analysis of primary and metastatic triple-negative breast cancer

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Cancer Biology & Medicine 2024年第9期21卷 784-798页

作者： Xiuzhi Zhu Xiaohan Ying Yin Liu Yunyi Wang Li chen Zhiming Shao Xi Jin Yizhou Jiang Zhonghua Wang Key Laboratory of Breast Cancer in Shanghai Shanghai Institute of Infectious Disease and Biosecurity Department of Oncology Shanghai Medical College Fudan University Department of Breast Surgery Fudan University Shanghai Cancer Center

Objective: Triple-negative breast cancer(TNBC) is a heterogeneous and aggressive cancer. Although our previous study classified primary TNBC into four subtypes, comprehensive longitudinal investigations are ***: We assembled a large-scale, real-world cohort comprised of 880 TNBC patients [465 early-stage TNBC(e TNBC) and 415 metastatic TNBC(m TNBC) patients] who were treated at Fudan University Shanghai Cancer Center. The longitudinal dynamics of TNBC subtypes during disease progression were elucidated in this patient cohort. Comprehensive analysis was performed to compare primary and metastatic lesions within specific TNBC ***: The recurrence and metastasis rates within 3 years after initial diagnosis in the e TNBC cohort were 10.1%(47/465). The median overall survival(OS) in the m TNBC cohort was 27.2 months [95% confidence interval(CI), 24.4±30.2 months], which indicated a poor prognosis. The prognostic significance of the original molecular subtypes in both e TNBC and m TNBC patients was confirmed. Consistent molecular subtypes were maintained in 77.5% of the patients throughout disease progression with the mesenchymal-like(MES) subtype demonstrating a tendency for subtype transition and brain metastasis. Additionally, a precision treatment strategy based on the metastatic MES subtype of target lesions resulted in improved progression-free survival in the FUTURE ***: Our longitudinal study comprehensively revealed the clinical characteristics and survival of patients with the original TNBC subtypes and validated the consistency of most molecular subtypes throughout disease progression. However, we emphasize the major importance of repeat pathologic confirmation of the MES subtype.

关键词： Triple-negative breast cancer metastasis molecular subtype overall survival primary tumor

The effects of local variations in conditions on carbon storage and release in the continental mantle

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National Science Review 2024年第06期 22-36页

作者： Stephen F.Foley Chunfei chen Dorrit E.Jacob School of Natural Sciences Macquarie University Research School of Earth Sciences Australian National University State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences

Recent advances indicate that the amount of carbon released by gradual degassing from the mantle needs to be revised upwards, whereas the carbon supplied by plumes may have been overestimated in the *** in rock types and oxidation state may be very local and exert strong influences on carbon storage and release mechanisms. Deep subduction may be prevented by diapirism in thick sedimentary packages,whereas carbonates in thinner sequences may be subducted. Carbonates stored in the mantle transition zone will melt when they heat up, recognized by coupled stable isotope systems(e.g. Mg, Zn, Ca). There is no single ‘mantle oxygen fugacity’, particularly in the thermal boundary layer(TBL) and lowermost lithosphere, where very local mixtures of rock types coexist. Carbonate-rich melts from either subduction or melting of the uppermost asthenosphere trap carbon by redox freezing or as carbonate-rich dykes in this zone. Deeply derived, reduced melts may form further diamond reservoirs, recognized as polycrystalline diamonds associated with websteritic silicate minerals. Carbon is released by either edge-driven convection,which tears sections of the TBL and lower lithosphere down so that they melt by a mixture of heating and oxidation, or by lateral advection of solids beneath rifts. Both mechanisms operate at steps in lithosphere thickness and result in carbonate-rich melts, explaining the spatial association of craton edges and carbonate-rich magmatism. High-pressure experiments on individual rock types, and increasingly on reactions between rocks and melts, are fine-tuning our understanding of processes and turning up unexpected results that are not seen in studies of single rocks. Future research should concentrate on elucidating local variations and integrating these with the interpretation of geophysical signals. Global concepts such as average sediment compositions and a uniform mantle oxidation state are not appropriate for small-scale processes; an increa

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Constitutive model of viscoelastic dynamic damage for the material of gas obturator in modular-charge howitzer

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Defence Technology 2024年第09期 203-216页

作者： Zhonggang Li Longmiao chen Yifan Li Yufeng Jia Quan Zhang School of Mechanical Engineering Nanjing University of Science and Technology Technology Center Shanxi North Machine-building Co. Ltd. Research and Development Department Kelong New Material Technology Co. Ltd.

In order to investigate the mechanical response behavior of the gas obturator of the breech mechanism,made of polychloroprene rubber(PCR), uniaxial compression experiments were carried out by using a universal testing machine and a split Hopkinson pressure bar(SHPB), obtaining stress-strain responses at different temperatures and strain rates. The results revealed that, in comparison to other polymers, the gas obturator material exhibited inconspicuous strain softening and hardening effects; meanwhile, the mechanical response was more affected by the strain rate than by temperature. Subsequently, a succinct viscoelastic damage constitutive model was developed based on the ZWT model, including ten undetermined parameters, formulated with incorporating three parallel components to capture the viscoelastic response at high strain rate and further enhanced by integrating a three-parameter Weibull function to describe the damage. Compared to the ZWT model, the modified model could effectively describe the mechanical response behavior of the gas obturator material at high strain rates. This research laid a theoretical foundation for further investigation into the influence of chamber sealing issues on artillery firing.

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Effects of capsaicin on intestinal health under antibiotic exposure

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Food Science and Human Wellness 2024年

作者： Qingying Fang Leilei Yu Fengwei Tian Wei chen Qixiao Zhai State Key Laboratory of Food Science and Resources， Jiangnan University School of Food Science and Technology， Jiangnan University National Engineering Research Center for Functional Food， Jiangnan University

Antibiotic exposure has adverse effects on intestinal immunity， metabolism， and gut microbiota (GM) composition， particularly by disturbing GM composition without short-term recovery. Capsaicin， a dietary irritant， is generally avoided during antibiotic therapy， but its mechanism remains unclear. To explore the effects of capsaicin on intestinal health during antibiotic administration， we conducted experiments in specific pathogen free (SPF) and germ-free (GF) mice and correlation analyses using 16S rRNA sequencing and non-targeted metabolomics to explore the protective role of the intestinal biological barrier. The results showed that additional supplementation of capsaicin under antibiotic exposure did not cause serious damage to the intestine， but had potential adverse effects on the structure， function， and metabolites of GM， including increasing the abundance of opportunistic pathogens (Mucispirillum and Aeromonas)， enriching metabolic pathways (arachidonic acid metabolism and lipopolysaccharide biosynthesis)， and metabolites associated with colon inflammation (N-acetylhistamine). In the absence of GM barrier， the beneficial function of capsaicin on the intestine was weakened and even induced adverse effects， suggesting that GM may have a certain mediating mechanism in the physiological function of capsaicin.

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