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An Analytic Model of Galactic Winds and Mass Outflows

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Chinese Journal of Astronomy and Astrophysics 2005年第4期5卷 327-346页

作者： Cheng-Gang shu Hou-Jun Mo shu-de mao Joint Center for Astrophysics Shanghai Normal University Shanghai 200234 Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 Max-Planck-Institut fuer Astrophysik Karl-Schwarzschild-Strasse 1 Postfach 1317 D-85741 Garching Germany Astronomy department University of Massachusetts Amherst MA 01003 USA Jodrell Bank Observatory Univ. of Manchester Macclesfield Cheshire SK11 9DL UK

Galactic winds and mass outflows are observed both in nearby starburst galaxies and in high-redshiff star-forming galaxies. We develop a simple analytic model to understand the observed superwind phenomenon with a discussion of the model uncertainties. Our model is built upon the model of McKee ＆ Ostriker for the interstellar medium. It allows one to predict how properties of a superwind,such as wind velocity and mass outflow rate, are related to properties of its starforming host galaxy, such as size, gas density and star formation rate. The model predicts a threshold of star formation rate density for the generation of observable galactic winds. Galaxies with more concentrated star formation activities produce superwinds with higher velocities. The predicted mass outflow rates are comparable to （or slightly larger than） the corresponding star formation rates. We apply our model to both local starburst galaxies and high-redshift Lyman break galaxies,and find its predictions to be in good agreement with current observations. Our model is simple and so can be easily incorporated into numerical simulations and semi-analytical models of galaxy formation.

关键词： galaxies starburst - galaxies ISM - galaxies kinematics and dynamics - galaxies formation and evolution

Strong and tough chitin hydrogel constructed by dehydration and rehydration strategy

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Nano Research 2024年第9期17卷 8192-8199页

作者： Rui-Rui Liu Li-Bo mao shu-Hong Yu Division of Nanomaterials and Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials and ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China Institute of Innovative Materials Department of Materials Science and EngineeringDepartment of ChemistrySouthern University of Science and TechnologyShenzhen 518055China

As a renewable,biocompatible,biodegradable soft material,chitin hydrogels have better advantages in stability,antibacterial activity,antifouling,cost,immunogenicity,and so on than most polymer ***,compared with other widely used polymer hydrogels with high strength and toughness,the practical applications of chitin-based hydrogels have been limited by their weak mechanical properties,such as cartilage repair and meniscus ***,we present the design and fabrication of chitin hydrogels with excellent mechanical strength and toughness by a dehydration and rehydration *** sequential dehydration and rehydration processes,the crystalline domains in the chitin hydrogels can be properly *** optimized crystallinity,the elastic modulus of the chitin hydrogels exceeds all previously reported values,and the fracture toughness is even comparable to some synthetic polymer hydrogels,while maintaining a high-water-content of about 80 wt.%.At the same water content,the mechanical properties of the chitin hydrogels are positively correlated with the hydrogel crystallinity,which proves that the change of mechanical properties of hydrogels is not simply dependent on weight *** hydrogels can be further strengthened by incorporating other biopolymers that are intrinsically weak,which makes the hydrogels promising for applications in fields such as cartilage repair and meniscus ***,the hydrogels enable loading and release of water-soluble and poorly water-soluble *** highly extendable strengthening and toughening strategy of chitin and chitin-based biopolymer hydrogels paves the way for their widely applications.

关键词： chitin hydrogel crystallinity rehydration chemical transformation strong and tough

A novel method for determining the resistivity of compressed superconducting materials

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Matter and Radiation at Extremes 2024年第4期9卷 1-3页

作者： Liling Sun Qi Wu shu Cai Yang Ding Ho-kwang mao Center for High Pressure Science and Technology Advanced Research Beijing 100094China Institute of Physics Chinese Academy of SciencesBeijing 100190China

The measurement of resistivity in a compressed material within a diamond anvil cell presents significant *** high-pressure exper-imental setup makes it difficult to directly measure the size changes induced by pressure in the three crystallographic directions of the *** this study,we introduce a novel and effective method that addresses these technical *** method is anticipated to offer a valuable foundation for high-pressure investigations on quantum materials,particularly those with anisotropic layered structures.

关键词： resistivity method foundation

Modulation of phase boundary and domain structures to engineer strain properties in BNT-based ferroelectrics

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Journal of Advanced Ceramics 2024年第7期13卷 967-975页

作者： Yule Yang Zhiyong Liu Pengrong Ren Yuqing mao Haijun Sun Bingliang Liang Pu mao Kun Guo Bing Xie Longlong shu School of Materials Science and Engineering Nanchang Hangkong UniversityNanchang 330063China School of Materials Science and Engineering Xi'an University of TechnologyXi’an 710048China School of Aircraft Engineering Nanchang Hangkong UniversityNanchang 330063China School of Physics and Materials Science Nanchang UniversityNanchang 330031China

Bismuth sodium titanate(BNT)ceramics exhibit outstanding strain responses but are unfavorable for application in high-sensitivity displacement actuators due to the large negative strain resulting from irreversible changes in their phase transition and domain ***,(1−x)Bi_(0.50)Na_(0.41)K_(0.09)TiO_(3)-xNaNbO_(3)(BNKT−xNN)solid solutions were prepared to improve the strain properties through the strategy of modulating the phase boundary and domain *** introduction of sodium niobate could effectively regulate the relative content of the tetragonal(P4bm)and rhombohedral(R3c)phases in the phase boundary *** ferroelectric-to-relaxor phase transition(TF−R)was reduced,and the ergodic relaxor(ER)state was nurtured at room *** zero-negative strain properties of S=0.41%and d33*=742 pm/V were achieved from the reversible transition between the ER and ferroelectric states under an applied electric field(x=0.04).Additionally,understanding the domain states via piezoelectric force microscopy(PFM)and firstorder reversal curve(FORC)revealed that the superior strain responses originated from the reversible inter-transformation of substable macrodomains and polar nanoregions(PNRs)in the phase *** study provides new insight into the interplay between the evolution of phase boundaries and domain structures and the strain properties of BNT-based ceramics.

关键词： bismuth sodium titanate(BNT) domain structure phase boundary strain response relaxor state

Growth of Black Holes and Their Host Spheroids in (Sub)mm-loud High-Redshift QSOs

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Chinese Journal of Astronomy and Astrophysics 2008年第1期8卷 12-24页

作者： Cai-Na Hao Xiao-Yang Xia shu-de mao Zu-Gan deng Hong Wu Tianjin Astrophysics Center Tianjin Normal University Tianjin 300384 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 Institute of Astronomy University of Cambridge Madingley Road Cambridge CB3 0HA UK Jodrell Bank Observatory University of Manchester Macclesfield Cheshire SK11 9DL UK Graduate School of Chinese Academy of Sciences Beijing 100049

We study the growth of black holes and stellar population in spheroids at high redshift using several （sub）mm-loud QSO samples. Applying the same criteria established in an earlier work, we find that, similar to IR QSOs at low redshift, the far-infrared emission of these （sub）mm-loud QSOs mainly originates from dust heated by starbursts. By combining low-z IR QSOs and high-z （sub）mm-loud QSOs, we find a trend that the star formation rate （M＊） increases with the accretion rate （Mace）. We compare the values of M＊/Macc for submm emitting galaxies （SMGs）, far-infrared ultraluminous/hypeduminous QSOs and typical QSOs, and construct a likely evolution scenario for these objects. The （sub）mm-loud QSO transition phase has both high Macc and M＊ and hence is important for establishing the correlation between the masses of black holes and spheroids.

关键词： galaxies active - galaxies evolution - galaxies high-redshift - galaxies interactions - quasars general - galaxies starburst

Biomimetic chitin hydrogel via chemical transformation

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Nano Research 2024年第2期17卷 771-777页

作者： Rui-Rui Liu Qian-Qian Shi Yu-Feng Meng Yong Zhou Li-Bo mao shu-Hong Yu Division of Nanomaterials&Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China College&Hospital of Stomatology Key Laboratory of Oral Diseases Research of Anhui ProvinceAnhui Medical UniversityHefei 230032China department of dental Implantology College&Hospital of StomatologyAnhui Medical UniversityHefei 230032China

Chitin hydrogel has been recognized as a promising material for various biomedical applications because of its biocompatibility and ***,the fabrication of strong chitin hydrogel remains a big challenge because of the insolubility of chitin in many solvents and the reduced chain length of chitin regenerated from *** herein introduce the fabrication of chitin hydrogel with biomimetic structure through the chemical transformation of chitosan,which is a water-soluble deacetylated derivative of *** reacetylation of the amino group in chitosan endows the obtained chitin hydrogel with outstanding resistance to swelling,degradation,extreme temperature and pH conditions,and organic *** chitin hydrogel has excellent mechanical properties while retaining a high water content(more than 95 wt.%).It also shows excellent antifouling performance that it resists the adhesion of proteins,bacteria,blood,and ***,as the initial chitosan solution can be feasibly frozen and templated by ice crystals,the chitin hydrogel structure can be either nacre-like or wood-like depending on the freezing method of the precursory chitosan *** to these anisotropic structures,such chitin hydrogel can exhibit anisotropic mechanics and mass transfer *** current work provides a rational strategy to fabricate chitin hydrogels and paves the way for its practical applications as a superior biomedical material.

关键词： chitin hydrogel biomimetic structure chemical stability mechanical strength antifouling

Association between Gene Polymorphisms and SNP-SNP Interactions of the Matrix Metalloproteinase 2 Signaling Pathway and the Risk of Vascular Senescence

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Biomedical and Environmental Sciences 2024年第2期37卷 146-156页

作者： LIAO Zhen Yu YANG shuo HU Song LIU Jia mao Yong Jun SUN shu Qin department of Geriatrics the Affiliated Hospital of Qingdao UniversityQingdao 266000ShandongChina department of Critical Care Medicine the Affiliated Hospital of Qingdao UniversityQingdao 266000ShandongChina

Objective This study aimed to explore the association of single nucleotide polymorphisms(SNP)in the matrix metalloproteinase 2(MMP-2)signaling pathway and the risk of vascular senescence(VS).Methods In this cross-sectional study,between May and November 2022,peripheral venous blood of151 VS patients(case group)and 233 volunteers(control group)were *** SNPs were identified in five genes encoding the components of the MMP-2 signaling pathway,assessed through carotid-femoral pulse wave velocity(cf PWV),and analyzed using multivariate logistic *** multigene influence on the risk of VS was assessed using multifactor dimensionality reduction(MDR)and generalized multifactor dimensionality regression(GMDR)*** Within the multivariate logistic regression models,four SNPs were screened to have significant associations with VS:chemokine(C-C motif)ligand 2(CCL2)rs4586,MMP2 rs14070,MMP2rs7201,and MMP2 *** of the T/C genotype of MMP2 rs14070 had a 2.17-fold increased risk of developing VS compared with those of the C/C genotype,and those of the T/T genotype had a19.375-fold increased ***2 rs4586 and MMP-2 rs14070 exhibited the most significant *** CCL2 rs4586,MMP-2 rs14070,MMP-2 rs7201,and MMP-2 rs1053605 polymorphisms were significantly associated with the risk of VS.

关键词： Vascular senescence Pulse wave velocity(PWV) Single nucleotide polymorphism(SNP) Matrix metalloproteinase 2(MMP-2) Extracellular matrix(ECM) Structural degradation Multifactor dimensionality reduction(MDR)

Correlation and Pathway Analysis of the Carbon,Nitrogen,and Phosphorus in Soil-Microorganism-Plant with Main Quality Components of Tea(Camellia sinensis)

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Phyton-International Journal of Experimental Botany 2024年第3期93卷 487-502页

作者： Chun mao Ji He Xuefeng Wen Yangzhou Xiang Jihong Feng Yingge shu College of Agriculture Guizhou UniversityGuiyangChina School of Geography and Resources Guizhou Education UniversityGuiyangChina

The contents of carbon(C),nitrogen(N),and phosphorus(P)in soil-microorganisms-plant signiﬁcantly affect tea quality by altering the main quality components of tea,such as tea polyphenols,amino acids,and ***,few studies have quantiﬁed the effects of these factors on the main quality components of *** study aimed to explore the interactions of C,N,and P in soil-microorganisms-plants and the effects of these factors on the main quality components of tea by using the path analysis *** results indicated that(1)The contents of C,N,and P in soil,microorganisms,and tea plants were highly correlated and collinear,and showed signiﬁcant correlations with the main quality components of tea.(2)Optimal regression equations were established to esti-mate tea polyphenol,amino acid,catechin,caffeine,and water extract content based on C,N,and P contents in soil,microorganisms,and tea plants(R^(2)=0.923,0.726,0.954,0.848,and 0.883,respectively).(3)Pathway analysis showed that microbial biomass phosphorus(MBP),root phosphorus,branch nitrogen,and microbial biomass carbon(MBC)were the largest direct impact factors on tea polyphenol,catechin,water extracts,amino acid,and caffeine content,*** carbon,root phosphorus,and leaf nitrogen were the largest indirect impact factors on tea polyphenol,catechin,and water extract content,*** carbon indirectly affected tea polyphenol content mainly by altering MBP *** phosphorus indirectly affected catechin content mainly by altering soil organic carbon *** nitrogen indirectly affected water extract content mainly by altering branch nitrogen *** research results provide the scientiﬁc basis for reasonable fertilization in tea gardens and tea quality improvement.

关键词： Soil-microorganisms-plant system carbon nitrogen phosphorus tea quality path analysis

Magmatic-hydrothermal Evolution and Mineralization Mechanisms of the Wangjiazhuang Cu(-Mo)deposit in the Zouping Volcanic Basin,Shandong Province,China:Constraints from Fluid Inclusions

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 679-700页

作者： shu Lei YANG Renchao SHEN Kun YANG deping mao Guangzhou LI Min LIU Pengrui MA Xiaodong Shandong Provincial Key Laboratory of depositional Mineralization and Sedimentary Minerals Shandong University of Science and TechnologyQingdaoShandong 266590China Key Laboratory of Gold Mineralization Processes and Resource Utilization MNR/Key Laboratory of Metallogenic Geological Processes and Resource UtilizationShandong Province/Shandong Institute of Geological SciencesJinan 250013China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdaoShandong 266237China

The Wangjiazhuang Cu(-Mo)deposit,located within the Zouping volcanic basin in western Shandong Province,China,is unique in this area for having an economic *** order to expound the metallogenetic characteristics of this porphyry-like hydrothermal deposit,a detailed fluid inclusion study has been conducted,employing the techniques of representative sampling,fluid inclusion petrography,microthermometry,Raman spectroscopy,LA-ICP-MS analysis of single fluid inclusions,as well as cathode fluorescence spectrometer analysis of host mineral *** deposit contains mainly two types of orebodies,***-dissemination-stockwork orebodies in the K-Si alteration zone and pegmatiticquartz sulfide veins above *** addition,minor breccia ore occurs *** types of fluid inclusions in the deposit and altered quartz monzonite are identified:L-type one-or two-phase aqueous inclusions,V-type vapor-rich inclusions with V/L ratios greater than 50%-90%,D-type multiphase fluid inclusions containing daughter minerals or solids and S-type silicate-bearing fluid inclusions containing mainly muscovite and *** petrography and fluid inclusion study has revealed a three-stage mineralization process,driven by magmatic-hydrothermal fluid activity,as ***,a hydrothermal fluid,separated from the parent magma,infiltrated into the quartz monzonite,resulting in its extensive K-Si alteration,as indicated by silicate-bearing fluid inclusions trapped in altered quartz *** is followed by the early mineralization,the formation of quartz veinlets and dissemination-stockwork *** the main mineralization stage,due to the participation and mixing of meteoric groundwater with magmatic-sourced hydrothermal fluid,the cooling and phase separation caused deposition of metals from the hydrothermal *** a result,the pegmatitic-quartz sulfide-vein ores *** the late mineralization stage,decreasing fluid salinity led to the formation of L-type aqueous

关键词： fluid inclusions fluid immiscibility mineralization mechanisms Wangjiazhuang Cu(-Mo)deposit