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Phosphine/Benzocyclone-based neutral nickel Catalysts for Ethylene Polymerization and Copolymerization with Polar Monomers

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ch.nese Journal of Polymer Science 2024年第2期42卷 202-212,I0007页

作者： Fei Wang li Pan Vladislav A.Tuskaev Svetlana ch.Gagieva Yue-Sheng li Tianjin Key Lab of Composite&Functional Materials School of Material Science and EngineeringTianjin UniversityTianjin300072China Department of chemistry Lomonosov Moscow State UniversityRussian Federation InstitutionLeninskie Gory 1Moscow119991Russian Federation A n nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesVavilova st.28Moscow119991Russian Federation

The efficient copolymerization of olefin with polar monomers using nickel-based catalysts presents a longstanding challenge. In this contribution, three phosphine-benzocyclone ligands and corresponding neutral nickel catalysts(ni1: Ar = Ph;ni2: Ar = 2-(C_(6)H_(5))C_(6)H_(4);ni3: Ar = 2-[2',6'-(Me O)_(2)-C_(6)H3]C_(6)H_(4)) were prepared and applied for the ethylene polymerization and copolymerization with polar monomers without any cocatalyst. The bulky substituent groups in complexes ni2 and ni3 contributed to high catalytic activities(up to 7.24×10^(6) and 9.04×10^(6)g·mol ni^(-1)·h^(-1), respectively), and produced high-molecular-weight polyethylene(Mw up to 545.7 k Da). Complex ni3 exhibited high activities for ethylene polymerization at the level of 10^(6) g·mol ni^(-1)·h^(-1) across a wide range from 30 ℃ to 120 ℃, exhibiting excellent high temperature tolerance. These nickel complexes were also effectively employed in the copolymerization of ethylene with methyl acrylate, ethyl acrylate, butyl acrylate and lauryl acrylate, producing copolymers with high molecular weights(Mw up to 80.5 k Da) and high polar monomer incorporation(up to 8.2 mol%). Microstructure analyses revealed that the introduction of large sterically hindered substituents facilitated the incorporation of polar functional units into the polymer backbone. This study demonstrates the potential of these nickel-based catalysts for efficient copolymerization of olefin with polar monomers.

关键词： neutral nickel catalyst Ethylene polymerization Copolymerization Polar acrylate monomers

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U-Pb dating of bastnäsite from the Vuoriyarvi massif:An example application for assessing the REE potential of carbonatite-related deposits

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Geoscience Frontiers 2024年第5期15卷 444-453页

作者： Evgeniy n.Kozlov Ekaterina n.Fomina Qiuli li Jiao li Geological Institute Kola Science Centre of the Russian Academy of SciencesApatity 184209Russia Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

The Vuoriyarvi massif is a Devonian multistage alkaline-ultrabasic carbonatite complex within the Kola alkaline *** carbonatites of the Vuoriyarvi massif contain abundant rare-earth mineralization mainly represented by ancylite-(Ce)and bastnäsite-(Ce).Ancylite was previously shown to have probably formed in the Devonian(ca.365 Ma)during an early postmagmatic *** geological observations have revealed a much later crystallization of bastnäsite but have not been able to specify the exact age of the *** in situ U-Pb dating of bastnäsite allowed us to constrain its ***äsite for this study was extracted from two varieties of dolomite carbonatite breccias cemented by(1)quartz-bastnäsite and(2)strontianite aggregates(hereafter bastnäsite-rich and strontianite-rich carbonatites–BRC and SRC,respectively).The obtained age estimations(237.7±9.8 Ma and 239.9±4.1 Ma,respectively)indicate that both studied rocks were formed during a single *** revealed age difference(~125 Ma)excludes the genetic link between the bastnäsite origin and regional alkaline magmatism,pointing out an additional source for the Vuoriyarvi bastnäsite-bearing ***,the obtained U-Pb ages provide strong evidence that a Triassic event is responsible for the occurrence of bastnäsite mineralization due to hydrothermal REE redistribution from the Devonian ancylite-rich *** of the REEs released during this process via dissolution of ancylite were precipitated in situ as bastnäsite,while strontium was transported and incorporated into *** Pb isotopic characteristics of bastnäsite(^(206)Pb/^(204)Pb=18.1±0.1,^(207)Pb/^(204)Pb=15.3±0.1,and^(207)Pb/^(206)Pb=0.84±0.01)are most probably inherited from the Devonian host rocks of the Vuoriyarvi massif involved in the Triassic *** signatures of Pb,Sr,and nd show that the depleted mantle and lower crust played the leading role in formation of the Vuoriyarvi alkaline

关键词： Bastnäsite REE Carbonatites U-Pb dating Vuoriyarvi Kola alkaline province

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Geochemistry and mineral chemistry of the armoor granitoids,eastern dharwar craton: implications for the redox conditions and tectono-magmatic environment

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Acta Geochimica 2024年第1期43卷 110-133页

作者： A.Ajay Kumar ch.Ashok Department of Geology Osmania UniversityHyderabad 500007India CSIR-national Geophysical Research Institute UppalHyderabad 500007India

The mineralogical and geochemical characteristics of the K-rich granites from the Armoor granitic rocks in the northeastern portion of the Eastern Dharwar Craton(EDC) are *** order to understand its physicochemical conditions,the petrogenesis of the granitoid was explained from biotite chemistry and geochemical *** of mineral chemistry expose that compositionally,K-feldspar and plagioclase in Armoor granite rocks range from An0,Ab_(3-5.9),Or_(94-96.9) and An_(5-29,-Ab71.9-94.9),Or_(0-1.5),*** mineral chemistry of biotite crystals exhibits composition that varies from primary to re-equilibrated primary *** biotites from the Armoor granites generally exhibit an I-type trend,with calc-alkaline parental magma in a subduction *** chemistry of granites displays magnetite(oxidized)series nature,which has oxygen fugacity(fO_(2))=-15.1 to-16.7(log_(10) bar),under high oxidizing *** and pressure estimates for the crystallization of Armoor granites based on biotite composition are T=612-716 ℃ and 1.0-0.4 kbar,***,these rocks are metaluminous to slightly peraluminous and magnesian,with calc-alkaline potassiumrich *** the ch.ndrite normalized REE diagram,the granites have positive europium anomalies;rich Sr/Y,(Dy/Yb)_(n) ratios and reduced Mg#,Rb/Sr,Rb,Sr indicate that the melting of earlier rocks,crystal accumulation and residual garnet source formed at high *** examined granites show that they are produced from the melting of crustal ***,the extensive analyses of the described Armoor granite suggest that they were produced by crust sources and developed under oxidizing conditions in subduction setting.

关键词： Armoor granites Oxygen fugacity Crystal accumulation Remelting Subduction

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Commentary on“Desialylated Platelets Maintain Immune Quiescence through Regulating Kupffer Cells”

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Research 2024年第3期6卷 621-623页

作者： ch.n li Craig n.Morrell Aab Cardiovascular Research Institute University of Rochester School of Medicine and DentistryRochesterNYUSA Department of Pharmacology and Physiology University of Rochester School of Medicine and DentistryRochesterNYUSA Department of Medicine University of Rochester School of Medicine and DentistryRochesterNYUSA Department of Microbiology and Immunology University of Rochester School of Medicine and DentistryRochesterNYUSA Department of Pathology and Laboratory Medicine University of Rochester School of Medicine and DentistryRochesterNYUSA.

Platelets have long been studied for their roles in hemostasis and vascular injury repair. However, there is a continually evolving and deepening understanding that platelets initiate and regulate responses to tissue injury and pathogens, leading to platelets now being considered immune modulatory cells [1]. Platelets actively participate in host immune responses directly through pathogen engulfing and killing, or by regulating both innate and adaptive immune responses to infection or tissue injury [2]. Activated platelets promote inflammatory responses to tissue injury or infection by direct contact dependent interactions with immune cells and through indirect interactions via released soluble factors. However, mice that are deficient in platelets have skewed T helper cell differentiation [3] and increased vascular permeability [4], implying poorly defined roles for platelets in maintaining healthy immune homeostasis.

关键词： Platelet homeostasis Immune

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Experimental evaluation of a“U”type earth-to-air heat exch.nger planned for narrow installation space in warm climatic conditions

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Energy and Built Environment 2024年第5期5卷 772-786页

作者： Ricardo Molina-Rodea Jorge Alejandro Wong-Loya Hugo Pocasangre-chávez Jennifer Reyna-Guillén Institute of Renewable Energies National Autonomous University of MexicoTemixcoMorelosMexico

The thermal performance of a“U”type earth-to-air heat exch.nger is presented in this experimental *** device has a serial-connected vertical *** wells where tubes were installed have a depth of fewer than 3 m and are separated every 1.5 m,using an installation area of *** experimentation was carried out in March in Morelos,Mexico when the environmental temperature reaches 35℃ during the *** performance of the device was measured and compared to the requirements of an office for cooling purposes within a university campus to reproduce the space restrictions found in urbanized *** using a small land surface,it is feasible for urbanized *** air temperature inside the“U”type earth-to-air heat exch.nger,the surrounding soil temperature,the airspeed,and the power consumed by the fan were *** air temperature and the fan’s power consumption data were obtained by modifying the airspeed in four constant values,from 1.3 m/s to 6.6 m/*** show that the device evaluated in this work has adequate thermal performance for cooling purposes compared to the requirements of an office.A decrease in air temperature was recorded in a range of 5.1℃ to 9.4℃.Over 70%of the total temperature difference was reached in the first well,where the average soil thermal disturbance at 5 cm was 2.8℃.The device achieved a maximum COP of 12.8 and a maximum effectiveness of 88.4%.With these results,it is concluded that the system is suitable for cooling purposes in areas with space *** work is novel since the dimensions available for installation in urbanized areas are considered and compared with the thermal requirements of an *** addition to the fact that there are no published works with vertical heat exch.ngers connected in series.

关键词： Low temperature geothermal energy Thermal performance Vertical heat exch.ngers Space restrictions in urbanized areas Geothermal direct uses

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Microbial electricity-driven anaerobic phenol degradation in bioelectrochemical systems

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Environmental Science and Ecotechnology 2024年第1期17卷 40-47页

作者： Shixiang Dai Falk Harnisch Micjel chávez Morejòn nina Sophie Keller Benjamin Korth Carsten Vogt Department of Environmental Microbiology Helmholtz Centre for Environmental Research GmbH-UFZLeipzigGermany Department of Isotope Biogeochemistry Helmholtz Centre for Environmental Research GmbH-UFZLeipzigGermany

Microbial electrochemical technologies have been extensively employed for phenol ***,previous research has yielded inconsistent results,leaving uncertainties regarding the feasibility of phenol degradation under strictly anaerobic conditions using anodes as sole terminal electron *** this study,we employed high-performance liquid chromatography and gas chromatography-mass spectrometry to investigate the anaerobic phenol degradation *** findings provide robust evidence for the purely anaerobic degradation of phenol,as we identified benzoic acid,4-hydroxybenzoic acid,glutaric acid,and other metabolites of this ***,no typical intermediates of the aerobic phenol degradation pathway were ***-chamber reactors(t0.4 V ***)exhibited a phenol removal rate of 3.5±0.2 mg L^(-1) d^(-1),while two-chamber reactors showed 3.6±0.1 and 2.6±0.9 mg L^(-1) d^(-1) at anode potentials of t0.4 and t 0.2 V,*** results also suggest that the reactor configuration certainly influenced the microbial community,presumably leading to different ratios of phenol consumers and microorganisms feeding on degradation products.

关键词： Microbial electroremediation Geobacter Extracellular electron transfer Anaerobic phenol degradation Microbial syntrophy

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Coke behavior with H_(2)O in a hydrogen-enriched blast furnace:A review

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 959-976页

作者： Feng Zhou Daosheng Peng Kejiang li Alberto n.Conejo Haotian liao Zixin Xiong Dongtao li Jianliang Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of chemical Engineering The University of QueenslandSt LuciaQLD 4072Australia Baosteel Central Research Institute(R&D Center of Wuhan Iron&Steel Co. Ltd.)Wuhan 430080China Shougang Research Institute of Technology Shougang Group Corporation Ltd.Beijing 100043China Beijing Key Laboratory of Green Recyclable Process for Iron and Steel Production Technology Beijing 100043China

Hydrogen-enriched blast furnace ironmaking has become an essential route to reduce CO_(2)emissions in the ironmaking ***,hydrogen-enriched reduction produces large amounts of H_(2)O,which places new demands on coke quality in a blast *** a hydrogen-rich blast furnace,the presence of H_(2)O promotes the solution loss *** result improves the reactivity of coke,which is 20%-30%higher in a pure H_(2)O atmosphere than in a pure CO_(2)*** activation energy range is 110-300 kJ/mol between coke and CO_(2)and 80-170 kJ/mol between coke and H_(2)***_(2)and H_(2)O are shown to have different effects on coke degradation *** review provides a comprehensive overview of the effect of H_(2)O on the structure and properties of *** exploring the interactions between H_(2)O and coke,several unresolved issues in the field requiring further research were *** review aims to provide valuable insights into coke behavior in hydrogen-rich environments and promote the further development of hydrogen-rich blast furnace ironmaking processes.

关键词： hydrogen ironmaking coke behavior blast furnace gasification microstructure kinetics

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Bile acids,gut microbiota,and therapeutic insights in hepatocellular carcinoma

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Cancer Biology & Medicine 2024年第2期21卷 144-162页

作者： Yang Song Harry ch Lau Xiang Zhang Jun Yu Institute of Digestive Disease and Department of Medicine and Therapeutics State Key Laboratory of Digestive DiseaseLi Ka Shing Institute of Health SciencesCUHK Shenzhen Research InstituteThe Chinese University of Hong KongHong KongChina Department of Gastroenterology Zhongshan Hospital Xiamen UniversityXiamen 361004China

Hepatocellular carcinoma(HCC)is a prevalent and aggressive liver *** interplay between bile acids(BAs)and the gut microbiota has emerged as a critical factor in HCC development and *** normal conditions,BA metabolism is tightly regulated through a bidirectional interplay between gut microorganisms and *** gut microbiota plays a critical role in BA metabolism,and BAs are endogenous signaling molecules that help maintain liver and intestinal *** note,dysbiotic ch.nges in the gut microbiota during pathogenesis and cancer development can disrupt BA homeostasis,thereby leading to liver inflammation and fibrosis,and ultimately contributing to HCC ***,understanding the intricate interplay between BAs and the gut microbiota is crucial for elucidating the mech.nisms underlying *** this review,we comprehensively explore the roles and functions of BA metabolism,with a focus on the interactions between BAs and gut microorganisms in ***,therapeutic strategies targeting BA metabolism and the gut microbiota are discussed,including the use of BA agonists/antagonists,probiotic/prebiotic and dietary interventions,fecal microbiota transplantation,and engineered *** summary,understanding the complex BA-microbiota crosstalk can provide valuable insights into HCC development and facilitate the development of innovative therapeutic approaches for liver malignancy.

关键词： Bile acid gut microbiota hepatocellular carcinoma therapeutics microbiota modulation

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Metagenomic analysis revealing the metabolic role of microbial communities in the free amino acid biosynthesis of Monascus rice vinegar during fermentation

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Food Science and Human Wellness 2024年第4期13卷 2317-2326页

作者： Hang Gao Jian Zhang li liu lijun Fu Yan Zhao Germán Mazza Xin Zhang Beijing Academy of Food Sciences 100068 BeijingChina Institute for Research and Development in Process Engineering Biotechnology and Alternative Energies(PROBIENCONICET-UNCo)8300 NeuquénArgentina

Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer *** is one of the major metabolites produced by microorganisms;however,the microbial metabolic network on FAA biosynthesis remains *** metagenomic analysis,this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar *** profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism *** metabolic network for FAA biosynthesis was then constructed,and the microbial distribution in different metabolic pathways was *** results revealed that 5 functional genera were closely involved in FAA *** study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation.

关键词： Monascus rice vinegar Metagenomic analysis Free amino acid synthesis Metabolic pathway Microbial distribution

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Greatly enhanced corrosion/wear resistances of epoxy coating for Mg alloy through a synergistic effect between functionalized graphene and insulated blocking layer

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Journal of Magnesium and Alloys 2024年第1期12卷 332-344页

作者： Z.Y.Xue X.J.li J.H.chu M.M.li D.n.Zou L.B.Tong School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082China

The poor corrosion and wear resistances of Mg alloys seriously limit their potential applications in various *** conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient *** the current study,we design a double-layer epoxy composite coating on Mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly *** outer layer is functionalized graphene(FG)in waterborne epoxy resin(WEP)and the inner layer is Ce-based conversion(Ce)*** FG sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects and improve the barrier *** Ce film connects the outer layer with the substrate,showing the transition *** corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare Mg alloy,and the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling *** synergistic effect derived from the FG sheet and blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of Mg alloys.

关键词： Mg alloy Functionalized graphene Epoxy coating Corrosion/wear resistance Blocking layer

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