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Inhibitory effect of procyanidin b2 and tannin acid on cholesterol esterase and their synergistic effect with orlistat

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Food Science and Human wellness 2024年第1期13卷 360-369页

作者： Xiangxin Li Yijing Pu Haitao jiang wenxiao Jiao wenjun Peng wenli Tian weibo jiang Xiaoming Fang Institute of Apicultural Research Chinese Academy of Agricultural SciencesBeijing 100093China College of Food Science and nutritional Engineering China Agricultural UniversityBeijing 100083China College of Food Science and Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China

This study was aimed to analyze the effect of procyanidin b2(PC)and tannin acid(TA)on the activities of cholesterol esterase(CEase)and the inhibitory mechanisms of enzymatic *** interaction mechanisms were investigated by enzymatic kinetics,multi-spectroscopy methods,thermodynamics analysis,molecular docking,and dynamic *** and TA could bind with CEase and inhibit the activity of enzyme in a mixed-competitive manner and non-competitive manner,which was verified by molecular docking simulations and dynamics ***,PC and TA showed the synergistic inhibition with ***,UVvis and the thermodynamic analysis revealed that the complexes were formed from CEase and inhibitors by noncovalent *** revealed by the circular dichroism results,both PC and TA decreased enzymatic activities by altering the conformations of *** inhibition of PC and TA on CEase might be one mechanism for its cholesterol-lowering effect.

关键词： Cholesterol esterase Polyphenols Interaction mechanisms Molecular dynamic simulation Synergistic effect

The coupling control of biological precursors and environmental factors onβ-carotane enrichment in alkaline lacustrine source rocks:A case study from the Fengcheng formation in the western Junggar basin,nw China

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Petroleum Science 2024年第2期21卷 836-854页

作者： Mao-Guo Hou Ming Zha Hua Liu Hai-Lei Liu jiang-Xiu Qu Ablimit Imin Xiu-Jian Ding Zhong-Fa jiang School of Geosciences China University of PetroleumQingdaoShandong266580China Research Institute of Exploration and Development Xinjiang Petroleum Administration BureauKaramayXinjiang834000China

The organic-rich mudstones and dolostones of the Permian Fengcheng Formation(Fm.)are typically alkaline lacustrine source rocks,which are typified by impressively abundantβ-*** β-carotane has been well acknowledged as an effective indicator of biological sources or depositional ***,the specific biological sources of β-carotane and the coupling control of biological sources and environmental factors on the enrichment of β-carotane in the Fengcheng *** *** on a comprehensive investigation of the bulk,molecular geochemistry,and organic petrology of sedimentary rocks and the biochemistry of phytoplankton in modern alkaline lakes,we proposed a new understanding of the biological precursors of β-carotane and elucidated the enrichment mechanism of β-carotane in the Fengcheng *** results show that the biological precursors crucially control the enrichment of β-carotane in the Fengcheng *** haloalkaliphilic cyanobacteria are the primary biological sources of β-carotane,which is suggested by a good positive correlation between the 2-methylhopane index,7-+8-methyl heptadecanes/C_(max),C_(29%),and β-carotane/C_(max)in sedimentary rocks and the predominance of cyanobacteria with abundantβ-carotene in modern alkaline *** enrichment of β-carotane requires the reducing condition,and the paleoredox state that affects the enrichment of β-carotane appears to have a *** paleoclimate conditions do not considerably impact the enrichment of β-carotane,but they have some influence on the water's paleosalinity by affecting evaporation and *** it does not directly affect the enrichment of β-carotane in the Fengcheng Fm.,paleosalinity does have an impact on the cyanobacterial precursor supply and the preservation conditions.

关键词： β-carotane enrichment Cyanobacterial input Environmental impact Alkaline lacustrine source rocks The Fengcheng formation

Energy beam-based direct and assisted polishing techniques for diamond:A review

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International Journal of Extreme Manufacturing 2024年第1期6卷 93-124页

作者： Zhuo Li Feng jiang Zhengyi jiang Zige Tian Tian Qiu Tao Zhang Qiuling wen Xizhao Lu Jing Lu Hui Huang Institute of Manufacturing Engineering Huaqiao UniversityXiamen 361021People’s Republic of China School of Mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongWollongongNSW 2522Australia College of Mechanical Engineering and Automation Huaqiao UniversityXiamen 361021People’s Republic of China State Key Laboratory of High Performance Tools Huaqiao UniversityXiamen 361021People’s Republic of China

Diamond is a highly valuable material with diverse industrial applications,particularly in the fields of semiconductor,optics,and high-power ***,its high hardness and chemical stability make it difficult to realize high-efficiency and ultra-low damage machining of *** address these challenges,several polishing methods have been developed for both single crystal diamond(SCD)and polycrystalline diamond(PCD),including mechanical,chemical,laser,and ion beam processing *** this review,the characteristics and application scope of various polishing technologies for SCD and PCD are ***,various energy beam-based direct and assisted polishing technologies,such as laser polishing,ion beam polishing,plasma-assisted polishing,and laser-assisted polishing,are *** current research progress,material removal mechanism,and infuencing factors of each polishing technology are *** some of these methods can achieve high material removal rates or reduce surface roughness,no single method can meet all the ***,the future development prospects and application directions of different polishing technologies are presented.

关键词： single crystal diamond polycrystalline diamond energy beam polishing technology material removal mechanism influencing factors

In situ crosslink polymerization induced long-lived multicolor supramolecular hydrogel based on modifiedβ-cyclodextrin

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Chinese Chemical Letters 2024年第2期35卷 374-379页

作者： Yonghui Sun Linnan jiang Yong Chen Yu Liu College of Chemistry State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

The construction of hydrogels with good mechanical properties and phosphorescent properties is full of ***,we report a supramolecular phosphorescent hydrogel with long lifetime,high tensile strength and self-healing property,which can be easily constructed through in-situ thermalinitiated polymerization of isocyanatoethyl acrylate-modifiedβ-cyclodextrin(β-CD-DA)and acrylatemodified adamantane(Ad-DA),acrylic acid(AA),followed by the non-covalent association with carbon dots(CnDs).The lifetime of phosphorescent hydrogel can reach 1261 ms at room temperature,and the quantum yield is 11%.Importantly,through the efficient triplet to singlet Förster resonance energy transfer(TS-FRET),the phosphorescent hydrogel shows the good phosphorescence energy transfer property for organic dyes Rhodamine b and Eosin Y with the delayed fluorescence lifetime up to 730 ms and 585 ms as well as the energy transfer efficiency(Φ_(ET))up to 99.9%and 99.3%,***,owing to the host-guest interactions betweenβ-CD-DA and Ad-DA,the three-dimensional cross-linked network phosphorescent hydrogel can be easily stretched to 18 times of its original length,and can achieve self-healing of the cut surfaces within 30 *** results will expand the scope of phosphorescent materials and provide new ideas and opportunities for materials science.

关键词： Room temperature phosphorescence Hydrogel Phosphorescence energy transfer Cyclodextrin Supramolecular interaction

Gravitational waves and primordial black hole productions from gluodynamics by holography

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 31-42页

作者： Song He Li Li Zhibin Li Shao-jiang wang Center for Theoretical Physics and College of Physics Jilin UniversityChangchun 130012China Max Planck Institute for Gravitational Physics(Albert Einstein Institute) Golm 14476Germany CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China

Understanding the nature of quantum chromodynamics(QCD)matter is important but challenging due to the presence of nonperturbative dynamics under extreme *** construct a holographic model describing the gluon sector of QCD at finite temperatures in the non-perturbative *** equation of state as a function of temperature is in good accordance with the lattice QCD ***,the Polyakov loop and the gluon condensation,which are proper order parameters to capture the deconfinement phase transition,also agree quantitatively well with the lattice QCD *** obtain a strong first-order confinement/deconfinement phase transition at Tc=276.5 Me V that is consistent with the lattice QCD *** on our model for a pure gluon hidden sector,we compute the stochastic gravitational waves and primordial black hole(PbH)productions from this confinement/deconfinement phase transition in the early *** resulting stochastic gravitational-wave backgrounds are found to be within detectability in the International Pulsar Timing Array and Square Kilometre Array in the near future when the associated productions of PbHs saturate the current observational bounds on the PbH abundances from the LIGO-Virgo-Collaboration O3 data.

关键词： AdS/QCD confinement/deconfinement phase transition gravitational wave primordial black hole

Palladium-Catalyzed anti-Markovnikov Halosulfonamidation of Unactivated Alkene

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Chinese Journal of Chemistry 2024年第5期42卷 464-470页

作者： b.w.n wang Jianxiao Li wanqing wu Huanfeng jiang State Key Laboratory of Pulp and Paper Engineering Key Laboratory of Functional Molecular Engineering of Guangdong ProvinceSchool of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhouGuangdong510641 China

Palladium-catalyzed regioselective amination of unactivated alkene remains a challenge and is of great ***,a three-component coupling of unactivated alkene,sulfonamide,and n-halo compounds accessing vicinal haloamine has been *** aminohalogenation represents a modular and regioselective *** electrophilic halogenating agent enables regioselective anti-Markovnikov aminopalladation and facilitates subsequent halogenation *** this protocol is characterized by gram-scale syntheses and late-stage *** note,the recovered byproduct phthalimide allows for reusing by conversion to the starting material.

关键词： Unactivated alkene anti-Markovnikov aminopalladation Vicinal haloamine Palladium catalysis Halosulfonamidation Selectivity n-Halo compounds

Primordial black holes and curvature perturbations from false vacuum islands

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 58-72页

作者： Rong-Gen Cai Yu-Shi Hao Shao-jiang wang School of Physical Science and Technology Ningbo UniversityNingbo 315211China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Asia Pacific Center for Theoretical Physics Pohang 37673Republic of Korea

Recently,much attention has been focused on the false vacuum islands that are flooded by an expanding ocean of true-vacuum bubbles slightly later than most of the other parts of the *** delayed decay regions will accumulate locally larger vacuum energy density by staying in the false vacuum longer than those already transited into the true vacuum.A false vacuum island with thus acquired density contrast of a super-horizon size will evolve locally from radiation dominance to vacuum dominance,creating a local baby Universe that can be regarded effectively as a local closed *** such density contrasts of super-horizon sizes can ever grow large enough to exceed the threshold of gravitational collapse,primordial black holes will form similar to those collapsing curvature perturbations on super-horizon scales induced by small-scale enhancements during *** not,such density contrasts can still induce curvature perturbations potentially observable *** this paper,we revisit and elaborate on the generations of primordial black holes and curvature perturbations from delayed-decayed false vacuum islands during asynchronous first-order phase transitions with fitting formulas convenient for future model-independent studies.

关键词： first-order phase transitions primordial black holes curvature perturbations

Developing Core-Shell nano-Structures in FeCrAl-ODS Ferritic Alloys with the Co-Addition of ni and Zr

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 364-372页

作者： wenquan Ding Jieli Ma Yong jiang Yiren wang Huiqun Liu Key Laboratory for nonferrous Materials of Ministry of Education School of Materials Science and EngineeringCentral South UniversityChangsha410083China national Key Laboratory for Powder Metallurgy Central South UniversityChangsha410083China

A new ni+Zr co-alloyed FeCrAl-ODS(oxide-dispersion-strengthened)ferritic alloy was fabricated by ball-milling and *** electron microscopy and atom probe tomography,the dispersive formation of high density core-shelled nano-particles of various sizes was confirmed with a common b2-niAl *** which,median-sized nano-particles(20-50 nm)typically have an Y_(4)Al_(2)O_(9)nano-core ofnm,ultra-fine nano-particles(nm have an Y_(4)Zr_(3)O_(12)nano-core ofnm,and larger-sized nano-particles(50-100 nm)incorporate an ultra-fine Y_(4)Al_(2)O_(9)nano-core and a few ultra-fine Y_(4)Zr_(3)O_(12)*** these nano-phases were highly coherent with the ferritic *** large Y--Al-O nano-oxides were *** total number density of ultra-fine nano-particles was estimated as~2×10^(23)m^(-3)with a mean size of 6.3 nm only,and accordingly,the new alloy achieved an excellent combination of strength and ductility at high temperatures.

关键词： FeCrAl Oxide-dispersion-strengthened(ODS)alloy Mechanical alloying nano-oxides Core-shell

A CFD study on the hydrodynamic response of a small-scale ice floe induced by a passing ship

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Journal of Hydrodynamics 2024年第2期36卷 290-299页

作者： Zongyu jiang Spyros Hirdaris Sasan Tavakoli Mikko Suominen Pentti Kujala Marine and Arctic Technology Department of Mechanical EngineeringAalto UniversityEspooFinland Global Ship Systems Centre ABS Hellenic SM LLC.AthensGreece Department of Infrastructure Engineering The University of MelbourneMelbourneAustralia

A Reynolds averaged navier-Stokes(RAnS)computational fluid dynamics(CFD)model is built to investigate the hydrodynamic response of a circular ice floe under the influence of a passing ship in calm *** ship,mirroring the KRISO Container Ship’s hull design,progresses near an ice floe whose diameter is 30%of the ship’s length and its thickness is 3 *** ship advances at a constant speed,which is handled by using the overset mesh *** study focuses on the ice floe’s motions and the hydrodynamic forces induced by three speeds and three transverse distances of the passing *** reveal that ship-generated wakes notably influence the ice floe’s motions,with a greater influence on sway than ***,the ship’s speed and proximity distinctly affect the ice floe’s motions.

关键词： Hydrodynamics ship-ice interactions ice floe Reynolds averaged navier-Stokes(RAnS)computational fluid dynamics(CFD)