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Pyridapeptides F–I,cyclohexapeptides from marine sponge-derived Streptomyces ***-4539

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Chinese Chemical Letters 2024年第7期35卷 341-344页

作者： Shuige Zhao Pengcheng Yan Peipei Liu Haishan Liu ning Li Peng fu Weiming Zhu Key Laboratory of Marine Drugs Ministry of Education of ChinaSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Key Laboratory for Marine Drugs and Bioproducts Laoshan LaboratoryQingdao 266237China School of Biological Science and Technology University of JinanJi'nan 250022China Key Laboratory for Biosensors of Shandong Province Biology InstituteQilu University of TechnologyJi'nan 250103China

Four new cyclohexapeptides,pyridapeptides F–I(1–4),were isolated from the fermentation broth of marine sponge-derived Streptomyces *** pyridapeptides F–H(1–3)are composed ofβ-hydroxyleucine,alanine,O-methylthreonine,hexahydropyridazine-3-carboxylic acid,5-hydroxytetrahydropyridazine-3-carboxylic acid,and(2S,3R,4E,6E)-2-amino-3–hydroxy-4,6-dienoic acid *** I(4)contains(2S,3R,4E,6E)-2-amino-3–hydroxy-8-methylnona-4,6-dienoic acid residue and a very rare glycose residue,*** structures were determined based on spectroscopic analysis and chemical *** G–I(2–4)have the 2,3,6-trideoxyhexose units glycosylated at theγ-OH-TPDA residue,displayed significant antiproliferative activity against four(PC9,MKN45,Hep G2,K562)or two(PC9,MKN45)human cancer cell lines.

关键词： Marine microorganism Streptomyces Cyclopeptide glycosides Pyridapeptides Antiproliferative activity

A new interacting capillary bundle model on the multiphase flow in micropores of tight rocks

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Petroleum Science 2024年第2期21卷 1099-1112页

作者： wen-Quan Deng Tian-Bo Liang wen-Zhong Wang Hao Liu Jun-Lin Wu fu-Jian Zhou National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

Surfactants are widely used in the fracturing fluid to enhance the imbibition and thus the oil recovery rate. However, current numerical models cannot capture the physics behind capillary imbibition during the wettability alteration by surfactants. Although the interacting capillary bundle(ICB) model shows potential in characterizing imbibition rates in different pores during wettability alteration, the existing ICB models neglect the influence of wettability and viscosity ratio on the imbibition behavior, making it difficult to accurately describe the oil-water imbibition behavior within the porous media. In this work,a new ICB mathematical model is established by introducing pressure balance without assuming the position of the leading front to comprehensively describe the imbibition behavior in a porous medium under different conditions, including gas-liquid spontaneous imbibition and oil-water *** the pore size distribution of a tight rock is known, this new model can predict the changes of water saturation during the displacement process in the tight rock, and also determine the imbibition rate in pores of different sizes. The water saturation profiles obtained from the new model are validated against the waterflooding simulation results from the CMG, while the imbibition rates calculated by the model are validated against the experimental observations of gas-liquid spontaneous imbibition. The good match above indicates the newly proposed model can show the water saturation profile at a macroscopic scale while capture the underlying physics of the multiphase flow in a porous medium at a microscopic scale. Simulation results obtained from this model indicate that both wettability and viscosity ratio can affect the sequence of fluid imbibition into pores of different sizes during the multiphase flow, where less-viscous wetting fluid is preferentially imbibed into larger pores while more-viscous wetting fluid tends to be imbibed into smaller pores. fur

关键词： Imbibition Multiphase flow Tight rock Interacting capillary bundle model Wettability

A review of microwave-metal discharge interaction:Mechanism,regulation,and application for synthesis of nanomaterials

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Nano Research 2024年第10期17卷 9225-9254页

作者： Yixuan Xie Ruiqian Shi Benwei fu Chengyi Song wen Shang Peng Tao Tao Deng State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China National Engineering Research Center of Special Equipment and Power System for Ship and Marine Engineering Shanghai 200030China

Placing metals within microwave ovens has been generally viewed as a dangerous practice because of occurrence of violent discharge,but in recent years such discharge phenomenon has attracted increasing attention and has enabled a variety of exciting *** this work,we provide a comprehensive review of fundamental understanding of microwave-metal discharge interaction and its state-of-the-art application for nanomaterials *** introduce the microscopic interaction between different categories of materials and the electric and magnetic field of *** microwave-metal interaction,we highlight its size-dependence and point out the influence of the oxide layer on the surface of *** discuss the required conditions for occurrence of discharge,microscopic formation mechanism,and characteristic features of microwave-metal discharge *** analyzing the influence from the microwave input,discharging metals,and surrounding discharging media,we discuss the strategy for systematical regulation of the discharge *** describe the applications of the microwave-metal discharge for facile synthesis of various functional nanomaterials including core-shell carbon/metal,metal oxides,metal chalcogenides,intermetallic compounds,metallic nanoparticles and metallic compounds,and organic ***,the challenges in precise characterization and dynamic regulation of the discharge process as well as exciting application opportunities are discussed.

关键词： microwave-metal interaction discharge microwave heating skin depth nanomaterial synthesis

Risk Assessment of Deep-Water Horizontal X-Tree Installation

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China Ocean Engineering 2024年第2期38卷 210-220页

作者： MENG wen-bo fu Guang-ming HUANG Yi LIU Shu-jie HUANG Liang GAOYong-hai CNOOC China Limited Zhanjiang BranchZhanjiang 524057China Key Laboratory of Unconventional Oil and Gas Development Ministry of Education(China University of Petroleum(East China))Qingdao 266580China

Due to the high potential risk and many influencing factors of subsea horizontal X-tree installation,to guarantee the successful completion of sea trials of domestic subsea horizontal X-trees,this paper established a modular risk evaluation model based on a fuzzy fault ***,through the analysis of the main process oftree down and combining the Offshore&Onshore Reliability Data(OREDA)failure statistics and the operation procedure and the data provided by the job,the fault tree model of risk analysis of the tree down installation was ***,by introducing the natural language of expert comprehensive evaluation and combining fuzzy principles,quantitative analysis was carried out,and the fuzzy number was used to calculate the failure probability of a basic event and the occurrence probability of a top ***,through a sensitivity analysis of basic events,the basic events of top events significantly affected were determined,and risk control and prevention measures for the corresponding high-risk factors were proposed for subsea horizontal X-tree down installation.

关键词： subsea horizontal X-tree risk assessment fuzzy fault tree modular risk evaluation model

{1012}twin–twin intersection-induced lattice rotation and dynamic recrystallization in Mg–6Al–3Sn–2Zn alloy

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Journal of Magnesium and Alloys 2024年第4期12卷 1529-1539页

作者： Bin-Jiang Lv Sen Wang fu-Hao Gao ning Cui Yi-Nan Li Tie-Wei Xu Feng Guo School of Mechanical and Automotive Engineering Qingdao University of Technology266520China Key Lab of industrial Fluid Energy Conservation and Pollution Control Qingdao University of Technology266520China

This study investigated the formation mechanism of new grains due to twin–twin intersections in a coarse-grained Mg–6Al–3Sn–2Zn alloy during different strain rates of an isothermal *** results of electron backscattered diffraction investigations showed that the activated twins were primarily{1012}tension twins,and 60°boundaries formed due to twin–twin intersections under different strain *** twin variants with 60°boundaries transformed into new grains through lattice rotations at a low strain rate(0.01 s^(−1)).At a high strain rate(10 s^(−1)),the regions surrounded by subgrain boundaries through high-density dislocation arrangement and the 60°boundaries transformed into new grains via dynamic recrystallization.

关键词： Mg alloy Twin-twin intersection Lattice rotation Dynamic recrystallization

Liquid-mediated Ostwald ripening of Ag-based clusters supported on oxides

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Nano Research 2024年第6期17卷 4971-4978页

作者： Conghui Liu Rongtan Li Yamei Fan Shiwen Li Xiaohui Feng Lu Feng Yanxiao ning Qiang fu School of Chemistry Dalian University of TechnologyDalian 116024China State Key Laboratory of Catalysis Chinese Academy of SciencesDalian Institute of Chemical PhysicsDalian 116023China

Reconstruction of supported nanocatalysts often occurs in gas-solid reactions and significantly affects the catalytic performance,yet it is much less explored in liquid-phase ***,we find that highly-dispersed Ag nanocatalysts,i.e.,AgOx clusters,supported on alumina,silica,and titania,can aggregate into larger Ag or Ag2O particles after immersing in liquid-phase media at room *** spontaneous aggregation of AgOx clusters in liquid water is attributed to liquid-phase Ostwald ripening through dissolution of AgOx clusters into water and subsequent redeposition to form Ag2O *** immersion into organic solvents such as ethanol leads to reduction of AgOx clusters and further growth into Ag *** work reveals that liquid-phase reaction media can induce substantial structural evolution of supported nanostructured catalysts,which should be carefully considered in liquid-solid interface catalytic reactions such as electrocatalysis,environmental catalysis,and organic synthesis in liquid phase.

关键词： Ag catalysts Ostwald ripening liquid phase media dissolution-deposition process

Targeted nanostrategies eliminate pre-metastatic niche of cancer

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Nano Research 2024年第6期17卷 5358-5373页

作者： Juan Wang ning Zhang Xiuping Ding Chengrui fu Xiaodong Li Baosheng Li Jianxun Ding Tianmeng Sun Key Laboratory of Organ Regeneration and Transplantation of Ministry of Education Institute of ImmunologyThe First HospitalJilin University1 Xinmin StreetChangchun 130061China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of Sciences5625 Renmin StreetChangchun 130022China Department of Radiation Oncology Shandong Cancer Hospital and InstituteShandong First Medical University and Shandong Academy of Medical Sciences440 Jiyan RoadJinan 250117China Department of orthopaedics The Second Hospital of Shandong UniversityShandong University247 Beiyuan StreetJinan 250033China State Key Laboratory of Molecular Engineering of Polymers Fudan University220 Handan RoadShanghai 200433China

Establishing a pre-metastatic niche(PMN)in secondary organs is a prerequisite for cancer *** advances in cancer therapy,the efficient inhibition of PMN formation remains a clinical *** advances in understanding the specific characteristics of PMN and advances in nanotechnology have provided hope for manipulating their microenvironments.A series of nanostrategies have been designed to eliminate the PMN,including the removal of pro-metastatic exosomes from the bloodstream for excretion via the intestines,the targeting and scavenging of myeloid-derived suppressor cells,fibroblasts,and critical extracellular matrix components,and the elimination of circulating tumor cells prior to colonization in distant *** review summarizes the underlying mechanisms of PMN formation,highlights the anti-PMN efficacy of currently reported nanostrategies,and underlines the unresolved questions.

关键词： nanoparticle controlled drug delivery pre-metastatic niche elimination metastasis suppression cancer therapy

Extreme drought with seasonal timing consistently promotes CH_(4) uptake through inconsistent pathways in a temperate grassland, China

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Journal of Arid Land 2024年第6期16卷 768-778页

作者： ZHANG wenwen PAN Yue wen fuqi fu Juanjuan HAO Yanbin HU Tianming YANG Peizhi College of Grassland Agriculture Northwest A&F UniversityYangling 712100China Binzhou Institute of Technology Weiqiao-UCAS(University of Chinese Academy of Sciences)Science and Technology ParkBinzhou 256606China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China

Methane(CH_(4))is a potent greenhouse gas that has a substantial impact on global warming due to its substantial influence on the greenhouse *** extreme precipitation events,such as drought,attributable to global warming that caused by greenhouse gases,exert a profound impact on the intricate biological processes associated with CH_(4) ***,the timing of extreme drought occurrence emerges as a pivotal factor influencing CH_(4) uptake,even when the degree of drought remains ***,it is still unclear how the growing season regulates the response of CH_(4) uptake to extreme *** an effort to bridge this knowledge gap,we conducted a field manipulative experiment to evaluate the impact of extreme drought on CH_(4) uptake during early,middle,and late growing stages in a temperate steppe of Inner Mongolia Autonomous Region,*** result showed that all extreme drought consistently exerted positive effects on CH_(4) uptake regardless of seasonal ***,the magnitude of this effect varied depending on the timing of season,as evidenced by a stronger effect in early growing stage than in middle and late growing ***,the pathways of CH_(4) uptake were different from seasonal *** drought affected soil physical-chemical properties and aboveground biomass(AGB),consequently leading to changes in CH_(4) *** structural equation model showed that drought both in the early and middle growing stages enhanced CH_(4) uptake due to reduced soil water content(SWC),leading to a decrease in NO_(3)–-N and an increase in pmoA ***,drought in late growing stage primarily enhanced CH_(4) uptake only by decreasing *** results suggested that seasonal timing significantly contributed to regulate the impacts of extreme drought pathways and magnitudes on CH_(4) *** findings can provide substantial implications for understanding how extreme droughts affect CH_(4) uptake and improve the prediction of

关键词： extreme climate greenhouse gas methane methanotrophs soil inorganic nitrogen

Improving Thermal-oxidative Aging Resistance of Styrene-butadiene Rubber by Antioxidant Loaded Silica Aerogel

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Chinese Journal of Polymer Science 2024年第8期42卷 1198-1209页

作者： Xue-Fei Ping Yu Wang Lu Liu fu-Yong Liu Hong-Wei He Pi Wang wen-wen Yu Qiang Zheng College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030032China Key Laboratory of Macromolecular Synthesis and functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310058China

The antioxidant N-isopropyl-N'-phenyl-p-phenylenediamine(4010NA)was dissolved in ethanol and impregnated into silica aerogel(SAG)via vacuum-pressure cycles,yielding composite particles(A-N)with enhanced sustained-release and reinforcing *** effect of A-N on the mechanical properties and thermal-oxidative aging resistance of styrene-butadiene rubber(SBR)vulcanizates was *** and BET assessments indicated that the loading efficiency of 4010NA in SAG reached 14.26%within ethanol's solu bility *** A-N into SBR vulcanizates significantly elevated tensile strength by 17.5%and elongation at break by 41.9%over those with fumed silica and ***,A-N notably enhanced the thermal-oxidative aging resistance of *** aging for 96 h at 100℃,the tensile strength and elongation at break of SBR with A-N sustained 70.09%and 58.61%of their initial values,respectively,with the retention rate of elongation at break being 62.8%higher than that of SBR with fumed silica and free *** study revealed that A-N composite particles significantly inhibited the crosslinking in SBR's molecular chains,reducing hardening and embrittlement during later thermal-oxidative aging stages.

关键词： Styrene-butadiene rubber Silica aerogel Loading modification Thermal-oxidative aging