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Changes of the trace metals in ice core during 1915-2016 in coastal eastern Antarctica

Advances in Climate Change Research 2024年第4期15卷 596-608页

作者： Jing-Wen LIU Chuan-Jin LI Gui-Tao shi Yan LIU Zhi-Heng DU Ming-Hu DING Shao-Peng GAO Cun-De XIAO shi-Chang KANG bo SUN State Key Laboratory of the Cryosphere Science Northwest Institute of the Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for Polar Science of State Oceanic Administration Polar Research Institute of ChinaShanghai 200136China Key Laboratory of Geographic Information Science(Ministry of Education) School of Geographic Sciences and Institute of Eco-ChongmingEast China Normal UniversityShanghai 200241China Institute of Tibetan Plateau and Polar Regions Meteorology Chinese Academy of Meteorological SciencesBeijing 100081China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Instituie of the Tibetan PlateauChinese Academy of SciencesBeijing 100101China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China

Antarctic trace metal records provide important information for grasping the influence of human activities on the environment over the last *** CA2016-75 ice core is located along the East Antarctic Zhongshan Station-Dome A,enhances the record of metals research in the East Antarctic region,and its high-resolution supplies data support for the study of high-frequency climatic drivers and the effect of human activities on the Antarctic environment.A thorough dataset on seven trace metals(Al,Fe,Mn,Cu,Zn,Ba and Pb)in a coastal ice core in eastern Antarctica during the previous 102 years(1915-2016)is presented in this *** has the lowest concentration(9.51±20.95 pg g^(-1)),and Ba has the highest concentration(36.57±51.35 ng g^(-1)).Notable variations are observed between the pre-1968 AD and post-1968 AD phases for Mn,Zn and *** abrupt,remarkable increase in the concentrations coincided with the change of metal smelting production in the southern *** addition to this,it may also be related to local Antarctic scientific research *** and Fe,the primary crustal elements,are essentially obtained from soil dust;Cu shows high crustal enrichment factors(EFc,>10),indicating that it is notably affected by anthropogenic ***,the anthropogenic activities in the Southern Hemisphere have had an impact on lead deposition in *** study not only enriches the trace metal historical record along the Zhongshan Station-Dome A but also provides a high-resolution ice core record,which is very crucial for the reconstruction of trace metal concentration changes in the last 100 years.

关键词： Eastern Antarctica Ice core Trace metals Human activities

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Highly Hydrolysis-Resistant Polyimide Fibers Prepared by Thermal Crosslinking with Inherent Carboxyl Groups

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Chinese Journal of Polymer Science 2024年第2期42卷 247-255,I0010页

作者： Can-Can Zhang Jun-Long Yang Ya-Jiang Huang Guang-xian Li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering of ChinaSichuan UniversityChengdu610065China

Easy hydrolysis in alkaline environments limits the use of polyimide fibers in environmental protection. The hydrolysis resistance levels of polyimide fibers can be improved by crosslinking of the macromolecular chains. In this work, crosslinked polyimide fibers(CPI fibers) were produced by intrinsic carboxyl decarboxylation for the first time. The thermal stability of the polyimide fibers containing the intrinsic carboxyl groups(PIC fibers) was studied, and the temperature of the decarboxylation-crosslinking reaction was determined to be 450 ℃. The PIC fibers were hotdrawn to initiate thermal crosslinking of the carboxyl groups and molecular chain orientation at high temperature. The CPI fibers had high tensile strengths(0.72-1.46 GPa) and compressive strengths(401-604 MPa). The oriented macromolecules and chemically crosslinked structure improved the tightness of the molecular chains and endowed the CPI fibers with excellent hydrolytic resistance. The CPI-50 fiber did not dissolve in a 0.5 wt% NaOH solution during heating at 90 ℃ for 10 h, and the tensile strength retention reached 87% when treated in 0.5 wt% NaOH solutions at 90 ℃ for 1 h, providing a guarantee for its application in alkaline corrosive environments.

关键词： Polyimide Carboxyl group Crosslinking Hydrolysis-resistance

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Degeneration of foundation cushion species induced by ecological constraints can cause massive changes in alpine plant communities

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Science China(Life Sciences) 2024年第4期67卷 789-802页

作者： Jianguo Chen Xufang Chen Lishen Qian Yazhou Zhang bo Li Honghua shi Lu Sun Christian Schöb Hang Sun Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China College of Resources and Environment Yunnan Agricultural UniversityKunming 650500China Área de Biodiversidad y Conservación Universidad Rey Juan CarlosMóstoles 28933Spain

Foundational cushion plants can re-organize community structures and sustain a prominent proportion of alpine biodiversity,but they are sensitive to climate *** loss of cushion species can have broad consequences for associated *** potential plant community changes with the population dynamics of cushion plants remain,however,*** eight plant communities along a climatic and community successional gradient,we assessed cushion population dynamics,the underlying ecological constraints and hence associated plant community changes in alpine communities dominated by the foundational cushion plant Arenaria *** population dynamics of Arenaria are attributed to ecological constraints at a series of life history *** functions are constrained by increasing associated beneficiary plants;subsequent seedling establishment is constrained by temperature,water and light availability,extreme climate events,and interspecific competition;strong competitive exclusion may accelerate mortality and degeneration of cushion *** with cushion dynamics,species composition,abundance and community structure gradually *** cushion plants completely degenerate,previously cushion-dominated communities shift to relatively stable communities that are overwhelmingly dominated by *** warming may accelerate the degeneration process of *** of this foundational cushion plant will possibly induce massive changes in alpine plant communities and hence ecosystem functions in alpine *** assessment of the population dynamics of foundation species is critical for an effective conservation of alpine biodiversity.

关键词： alpine ecosystem biodiversity change climate change plant community dynamics foundation species global warming population dynamics

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CCDC181 is required for sperm flagellum biogenesis and male fertility in mice

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Zoological Research 2024年第5期45卷 1061-1072页

作者： xiang-Jun Zhang Xiao-Ning Hou Jian-Teng Zhou Bao-Lu shi Jing-Wei Ye Meng-Lei Yang Xiao-Hua Jiang bo Xu Li-Min Wu Qing-Hua shi Division of Reproduction and Genetics First Affiliated Hospital of University of Science and Technology of China(USTC)Hefei National Laboratory for Physical Sciences at MicroscaleSchool of Basic Medical SciencesDivision of Life Sciences and MedicineBiomedical Sciences and Health Laboratory of Anhui ProvinceInstitute of Health and MedicineHefei Comprehensive National Science CenterUniversity of Science and Technology of ChinaHefeiAnhui 230001China

The structural integrity of the sperm flagellum is essential for proper sperm *** defects can result in male infertility,yet the precise mechanisms underlying this relationship are not fully ***181,a coiled-coil domain-containing protein,is known to localize on sperm flagella and at the basal regions of motile *** this knowledge,the specific functions of CCDC181 in flagellum biogenesis remain *** this study,Ccdc181 knockout mice were *** absence of CCDC181 led to defective sperm head shaping and flagellum ***,the Ccdc181 knockout mice exhibited extremely low sperm counts,grossly aberrant sperm morphologies,markedly diminished sperm motility,and typical multiple morphological abnormalities of the flagella(MMAF).Additionally,an interaction between CCDC181 and the MMAF-related protein LRRC46 was identified,with CCDC181 regulating the localization of LRRC46 within sperm *** findings suggest that CCDC181 plays a crucial role in both manchette formation and sperm flagellum biogenesis.

关键词： Male infertility CCDC181 MMAF Spermiogenesis Flagellum biogenesis

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Creep property and microstructural evolution of DD11 alloy under high temperature and low stress

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Rare Metals 2024年第2期43卷 810-816页

作者： Yan-Fei Liu Jiang-bo Sha Yun-Song Zhao Chen-Guang Liu Yuan-Yuan Guo Jian Zhang Yu-shi Luo School of Materials Science and Engineering Beihang UniversityBeijing100191China Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical MaterialsBeijing100095China

In this paper,the interrupted and ruptured creep tests were carried out in a novel second generation single crystal superalloy named DD11 at 1100℃/130 *** alloy exhibited typical creep curve including primary,steady,and tertiary three creep *** microstructural evolution at different stages of the creep were analyzed by scanning electron microscopy(SEM)and transmission electron microscopy(TEM).The results show that theγ′phases transform into rafted structure at the early stage of the steady creep and keep stable during the steady creep *** the creep goes on,the rafted structure further coarsens and the topological inversion *** addition,at the primary creep,the dislocations mainly move in theγmatrix and pile up in theγ/γ′interface since the matrix channels widen *** formation of the regular interfacial dislocation networks occurs at the early stage of the steady *** the low stress,the dominated deformation mechanism during steady creep stage is the climbing of the〈010〉type edge ***,the effect of the deformation mechanism on creep property was discussed in detail.

关键词： DD11 alloy Creep property Interrupted creep test Rafted structure Deformation mechanism

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Long-wave infrared emission properties of strain-balanced InAs/In_(x)Ga_(1-x)As_(y)Sb_(1-y)type-Ⅱsuperlattice on different substrates

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Rare Metals 2024年第7期43卷 3194-3204页

作者： Chao shi Xuan Fang Hong-Bin Zhao Deng-Kui Wang Xi Chen Dan Fang Dong-bo Wang Xiao-Hua Wang Jin-Hua Li State Key Laboratory of High Power Semiconductor Lasers School of PhysicsChangchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Advanced Materials for Smart Sensing China General Research Institute for Nonferrous MetalsBeijing 100088China Department of Opto-Electronic Information Science School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

High-performance type-Ⅱsuperlattices ofⅢ-Ⅴsemiconductor materials play an important role in the development and application of infrared optoelectronic *** the quality of epitaxial materials and clarifying the luminescent mechanism are of great significance for practic al applic *** this work,strain-balanced and high-quality In As/In_(x)Ga_(1-x)As_(y)Sb_(1-y)superlattices without lattice mismatch were achieved on InAs and GaSb substrates *** grown on In As substrate could exhibit higher crystal quality and surface flatness based on high-resolution X-ray diffraction(HRXRD)and atomic force microscopy(AFM)measurements'***,the strain distribution phenomenon from geometric phase analysis indicates that fluctuations of alloy compositions in superlattices on GaSb substrate are more *** addition,the optical properties of superlattices grown on different substrates are discussed *** of the difference in fluctuations of element composition and interface roughness of superlattices on different substrates,the superlattices grown on In As substrate would have higher integral intensity and narrower full-width at half maximum of long-wave infrared ***,the thermal quenching of emission intensity indicates that the superlattices grown on the In As substrate have better recombination ability,which is beneficial for increasing the operating temperature of infrared optoelectronic devices based on this type of superlattices.

关键词： Photoluminescence Alloy compositions fluctuations InAs(Sb)/In_(x)Ga_(1-x)As_(y)Sb_(1-y) Type-Ⅱsuperlattice Substrate

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Mulberry leaf supplementation inhibits skatole deposition by regulating gut microbiota and upregulating liver cytochrome P4501A1 expression in finishing pigs

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Animal Nutrition 2024年第1期16卷 34-44页

作者： Yuqing Sun Xiaoming Men Tianbao Lin bo Deng shi Zhong Jinxi Huo Kaipeng Qin Zhiqiang Lv Ziwei Xu Yougui Li Institute of Sericulture and Tea Zhejiang Academy of Agricultural Sciences298 Deshengzhong RoadShangchengHangzhou 310021China Institute of Animal Husbandry and Veterinary Science Zhejiang Academy of Agricultural Sciences298 Deshengzhong RoadShangchengHangzhou 310021China

Skatole,a strong fecal odor substance,is generated through microbial degradation of tryptophan in the animal *** easily accumulates in adipose tissue and affects meat *** this study,the effect of mulberry leaf supplementation on skatole in finishing pigs was *** a 35-day trial,20 finishing pigs(barrows and gilts)were fed with a basal diet or basal diet with 6%mulberry *** performance of the pigs(n=10)was automatically recorded by a performance-testing feeder system and 8 pigs in each treatment were slaughtered and sampled for the remaining *** and short-chain fatty acids were detected using HPLC and gas chromatography,*** microbiota were analyzed using 16S r RNA gene *** metabolomics analysis of feces and serum was performed with UHPLC-MS/*** major cytochrome P450(CYP)enzymes that catalyze skatole degradation in the liver were tested by using RT-PCR and Western *** of major bioactive compounds in mulberry leaves on the CYP genes were verified in the hepatic cell line Hep G2 in an in vitro test(n=3).In finishing pigs,mulberry leaf supplementation had no significant effect on the average daily gain,average daily feed intake,and feed conversion ratio(P>0.05),but reduced skatole levels in feces,serum,and backfat(P<0.05),and increased acetic acid levels in feces(P=0.027).Mulberry leaf supplementation decreased the relative abundance of the skatole-producing bacteria Megasphaera and Olsenella(P<0.05).Indole-3acetic acid,the intermediate that is essential for skatole production,was significantly reduced in feces by mulberry leaf supplementation(P<0.05)and was positively correlated with skatole content in feces(P=0.004).In pigs treated with mulberry leaves,liver CYP1A1 expression was increased(P<0.05)and was negatively correlated with skatole content in backfat(P=0.045).The in vitro test demonstrated that mulberry leaf polyphenols and polysaccharides could directly stimulate CYP1A1 expression in

关键词： Pig Skatole Mulberry leaf Microbiota Cytochrome P450

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Competitive assembling strategy to construct carbon nitride homojunctions for boosting photocatalytic performance

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Journal of Materials Science & Technology 2024年第5期172卷 23-32页

作者： Hua-Wei Zhang Yuan-Yuan Li bo Li Jing-Hui shi Tao Huang Gui-Fang Huang Anlian Pan Wangyu Hu Wei-Qing Huang School of Physics&Electronic Engineering Zhengzhou University of Light IndustryZhengzhou 450002China Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education&Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics and Devices School of Physics and ElectronicsHunan UniversityChangsha 410082China College of Materials Science and Engineering Hunan UniversityChangsha 410082China

both morphology and composition have a great influence on the properties and functions of materials,however,how to rational modulate both of them to achieve their synergistic effects has been a longstanding ***,we demonstrate a competitive assembling strategy for the construction of metal-free graphite carbon nitride(CN)homojunctions in which morphology and composition can be easily controlled simultaneously by only changing the ratio of assembly raw *** homojunctions are comprised of porous nanotubular S-doped CN(SCN)grafted with CN nanovesicles,which are derived from thermal polycondensation of melamine-thiocyanuric acid(M-T)/melamine-cyanuric acid(M-C)supramolecular hybrid *** unique architecture and component engineering endows the novel SCN-CN homojunction with abundant active sites,enhanced visible trapping ability,and intimate interface *** a result,the synthesized SCN-CN homojunctions demonstrate high photocatalytic activity for hydrogen evolution and pollutant *** developed strategy opens up intriguing opportu-nities for the rational construction of intricate metal-free heterostructures with controllable architecture and interfacial contact for applications in energy-related fields.

关键词： Competitive assembling strategy Supramolecular hybrid blocks Homojunctions Graphite carbon nitride Photocatalytic

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Two-dimensional bifunctional electrocatalyst(Mo-NiFe-LDH)with multilevel structure for highly efficient overall water splitting

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Rare Metals 2024年第6期43卷 2613-2622页

作者： Bao-Jie Zhang Bin Chang shi-Peng Qiu Gang Zhao Xiao Wang Xi-Jin Xu Lan Mu Wen-bo Liao Xiao-Jing Dong School of Physics and Technology University of JinanJinan 250000China KAUST Catalysis Center(KCC) King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Kingdomof SaudiArabia School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China School of Physics and Physical Engineering Qufu Normal UniversityQufu273100China

To effectively address energy challenges,it is crucial to explore efficient and stable bifunctional nonprecious metal *** this study,a Mo-doped nickeliron layered double hydroxide with flower-cluster architecture was successfully prepared by a one-step hydrothermal method,which demonstrated a good water splitting *** an appropriate amount of Mo doping,some lattice distortions in the material provided reactive sites for the adsorption and conversion of intermediates,thus optimising the charge distribution of the ***,the multidimensional void structures formed after doping had a larger specific surface area and accelerated the penetration of the electrolyte,which significantly improved the activity of the catalyst in alkaline *** 10 mA·cm^(-2),the hydrogen and oxygen evolution overpotentials of Mo-doped nickel-iron double hydroxides(Mo-NiFe LDH/NF-0.2)were 167 and 220 mV,respectively,with an excellent durability up to 24 *** the Mo-NiFe LDH/NF-0,2 catalyst was used as the cathode and anode of an electrolytic cell,the catalyst achieved a current density of 10 mA·cm^(-2)at an applied voltage of 1.643 *** study provides a novel approach for designing excellent bifunctional electrocatalysts containing nonprecious metals.

关键词： Bifunctional electrocatalysts 2D multilevel structure Overall water splitting Mo-doped Ni-Fe LDH

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Liquid-metal microgrid stretchable electronics based on bionic leaf veins with ultra-stretchability and high conductivity

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Rare Metals 2024年第6期43卷 2747-2757页

作者： Xi-Di Sun Jun-Yang An Yi-Qi Sun Xin Guo Jing Wu Jiang-bo Hua Meng-Rui Su Yi shi Li-Jia Pan Collaborative Innovation Center of Advanced Microstructures School of Electronic Science and EngineeringNanjing UniversityNanjing 210093China

Stretchable electronics that monitor joint activity and treat diseases based on liquid metal could be used in the development of healthcare *** devices can be seamlessly integrated with human ***,most high-precision microstructures and complex patterns are difficult to fabricate due to the limitations of conventional fabrication solutions,resulting in suboptimal performance under practical ***,a liquid-metal stretchable system utilizing natural leaf veins was reported as microstructures,which was based on a biomimetic concept and utilized an all-solution process for the preparation of complex *** systems are ultra-high tensile(800%tensile strain),environmentally stable(20 days)and mechanically durable(300-cycle).The system can accurately recognize the wearer's finger bending level as well as simple gesture *** the same time,the system acts as a wearable heater,which can realize the fast heating behavior of heating up to 50℃in 3 min under the human body-safe voltage(1.5 V).The tensile stability is demonstrated by the heterogeneous integration of lasers(405 nm)with the system interconnects for a stretchable and wearable light source.

关键词： Stretchable electronics Liquid metal Stretchable conductor Vein Bionicist electronics

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