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Potassium isotopic signatures of modern offshore detrital sediments from different climatic regimes and the implications

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Science China Earth Sciences 2024年第2期67卷 405-419页

作者： Jun MU Tianyu CHEN Qian YU Shichao AN Jianfang CHEN Xuefa SHI Weiqiang LI State key laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjing210023China Ministry of Education key laboratory for coast and island development School of Geography and Ocean ScienceNanjing UniversityNanjing210023China State key laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou310012China key laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao266061China

Potassium isotopes are a novel tracer for continental *** K isotope studies on chemical weathering generally targeted weathering profiles under a particular climate region,yet the effects of chemical weathering on K isotopes under different climatic backgrounds remain ***,little is known about the K isotope signatures of modern unconsolidated detrital ***,we report K isotopic data of surficial seafloor sediments from continental shelves along the east coast of China(ECC),as well as those around the tropical Hainan island in the northern South China *** ECC sediments have a relatively narrow distribution ofδ^(41)K(with reference to NIST3141a)values,which range from(-0.40±0.01)‰to(-0.57±0.04)‰,with an average of(-0.51±0.09)‰.By contrast,δ^(41)K values of Hainan offshore sediments display a larger variation,ranging from(-0.28±0.07)‰to(-0.67±0.02)‰.Theδ^(41)K values of Hainan offshore sediments exhibit negative correlations with the chemical index of alteration(CIA),Al/K,Ti/K,and total iron(FeT),which underlines the control of chemical weathering on K isotopic signatures of detritus inputs into *** also measured Mg isotope compositions for the same samples;interestingly,the variability inδ^(26)Mg of the samples is small(~0.24‰)for all ECC and Hainan offshore sediments,andδ^(26)Mg values do not show clear correlations with indexes of chemical *** study demonstrates the link between K isotopic variability of detrital sediments and climatic conditions including rainfall intensity,which indicates that K isotopes of the detrital component of marine sediments could be applied to study Earth’s climate in deep ***δ^(41)K values of the offshore detrital sediments are significantly less variable than those of pelagic marine sediments,highlighting the importance of distinguishing the effects of diagenesis and neoformation of clay minerals from continental weathering in attempts to study deep-time climate-weathering

关键词： Potassium isotopes Magnesium isotopes Chemical weathering Detrital sediments Climatic regimes Mean annual precipitation

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Zeolites for the separation of ethylene,ethane,and ethyne

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Frontiers of Chemical Science and Engineering 2024年第9期18卷 137-146页

作者： Binyu Wang Qiang Li Haoyang Zhang Jia-Nan Zhang Qinhe Pan Wenfu Yan State key laboratory of Inorganic Synthesis&Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China key laboratory of Advanced Energy Catalytic and Functional Materials Preparation College of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450012China key laboratory of Advanced Materials of Tropical island Resources(Ministry of Education) School of Chemistry and Chemical EngineeringHainan UniversityHaikou 570228China

The cost-effective separation of ethylene(C_(2)H_(4)),ethyne(C_(2)H_(2)),and ethane(C_(2)H_(6))poses a significant challenge in the contemporary chemical *** contrast to the energy-intensive high-pressure cryogenic distillation process,zeolite-based adsorptive separation offers a low-energy *** review provides a concise overview of recent advancements in the adsorptive separation of C_(2)H_(4),C_(2)H_(2),and C_(2)H_(6)using zeolites or zeolite-based *** commences with an examination of the industrial significance of these compounds and the associated separation ***,it systematically examines the utilization of various types of zeolites with diverse cationic species in such separation *** then it explores how different zeolitic structures impact adsorption and separation capabilities,considering principles such as cation-πinteraction,π-complexation,and steric separation concerning C_(2)H_(4),C_(2)H_(2),and C_(2)H_(6)***,it discusses methods to enhance the separation performance of zeolites and zeolite-based adsorbents,encompassing structural design,modifications,and ion exchange ***,it summarizes current research trends and future directions,highlighting the potential application value of zeolitic materials in the field of C_(2)H_(4),C_(2)H_(2),and C_(2)H_(6)separation and offering recommendations for further investigation.

关键词： zeolite ethylene ethane cation-πinteraction π-complexation

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The Middle and Late Holocene climate change in Bohai Bay revealed by diatom proxy

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Journal of Oceanology and Limnology 2024年第05期 1493-1506页

作者： Zhiwen SHANG Jianfen LI Fu WANG Hong WANG Tianjin Centre China Geological Survey key laboratory of coastal Geo-environment China Geological Survey Tianjin key laboratory of coast Geological Processes and Environmental Safety

A total of 98 samples from two boreholes in shallow sea area and two oyster reefs in adjacent coastal plain in the northwestern coast of Bohai Bay were collected for diatom analyses and species identification. The ratio of the marine species Thalassionema nitzschioides to the intertidal-coastal species complex Cyclotella striata/stylorum serves as a novel proxy for assessing the strength of marine influence. Chronological data, corrected for the local residence time effect, facilitated the construction of a diatom proxy-based marine influence curve for the study area. This curve delineates the dynamics of marine influence and their correlations with paleo-climate fluctuations and the East Asian monsoon variability, as well as their role in chenier formation. Results include:(1) eight periods of intensified marine influence have been documented since 7 000 a BP in the study area. The peak of each period, as determined by the diatom proxy, corresponds closely to the warm climatic phases and stronger East Asian summer monsoons, suggesting that the peaks marine influence indicate typically the periods of climatic warmth and monsoon activity intensification in the region;(2) a strong correlation exists between the development of cheniers and marine influence, and chenier formation began with the increasing marine influence and terminated at the end of warm periods as marine influence weakens. The climatic changes in the coastal area, as indicated by the diatom proxy, hold significant potential for future related research endeavors.

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GAMYB transcription factor LoMYB65 from lily plays a vital role in pollen development

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Horticultural Plant Journal 2024年第1期10卷 223-238页

作者： Xinyue Liu Ling He Ze Wu Nianjun Teng key laboratory of Landscaping Agriculture Ministry of Agriculture and Rural AffairsCollege of HorticultureNanjing Agricultural UniversityNanjingJiangsu 210095China key laboratory of Biology of Ornamental Plants in East China National Forestry and Grassland AdministrationCollege of HorticultureNanjing Agricultural UniversityNanjingJiangsu 210095China Jiangsu Graduate Workstation of Nanjing Agricultural University and Nanjing Oriole island Modern Agricultural development Co. Ltd.NanjingJiangsu 210043China

Lily(Lilium spp.)is an important horticultural crop,but its use is limited due to serious pollen contamination *** are many studies on pollen development in model plants,but few on flower crops such as ***(GA)is a large class of hormones and plays an important role in plant vegetative growth and reproductive *** is a group of the R2R3-MYB family upregulated by gibberellin,and plays an important role in anther ***,we isolated a novel GAMYB,named LoMYB65,from lily,which was closely related to the AtMYB65 and AtMYB33 in *** quantitative PCR results showed that LoMYB65 was mainly expressed in lily ***65 could be activated by 288μmol·L^(-1)GA3treatment and the LoMYB65 protein was located in the nucleus and cytoplasm,and had transactivation in yeast and tobacco leaf *** conserved motif within 226 amino acids of the C-terminal of LoMYB65 contributed to its *** of LoMYB65 caused dwarf phenotype,unnormal tapetum development,less seeds of siliques in transgenic Arabidopsis plants,the transgenic plants showed partly male ***,silencing of LoMYB65 with VIGS(Virus Induced Gene Silencing)in lily anthers caused unnormal pollen development and reduced the pollen *** of LoMYB65 in Arabidopsis and silencing of LoMYB65 in lily resulted in decreased pollen counts,so we speculate that LoMYB65 may be ***,these findings suggest that LoMYB65 may play an important role in anther development and pollen formation in ***65 may provide a useful candidate gene for pollenless breeding of lily.

关键词： Lily Anther development Pollen pollution GAMYB VIGS

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Bird specimen number linked with species trait and climate niche breadth

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Avian Research 2024年第1期15卷 108-115页

作者： Xiaoyu Duan Xiongwei Huang Jingya Zhang Shuo Lv Gang Song Yanping Wang Gang Feng Ministry of Education key laboratory of Ecology and Resource Use of the Mongolian Plateau&Inner Mongolia key laboratory of Grassland Ecology School of Ecology and EnvironmentInner Mongolia UniversityHohhot010020China key laboratory of Marine Biotechnology of Fujian Province Institute of OceanologyCollege of Marine SciencesFujian Agriculture and Forestry UniversityFuzhou350002China key laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijing100101China laboratory of island Biogeography and Conservation Biology College of Life SciencesNanjing Normal UniversityNanjing210023China

Biological specimens are fundamental for taxonomy and flora/fauna *** importantly,they also play crucial roles in recording environmental impacts on morphology and behavior,which is vital for biodiversity research and ***,there are few systematic studies on the patterns and drivers of bird specimen number at regional *** study is the first attempt to examine the relationships between bird specimen number and species traits as well as climate niche breadth in China,aiming to answer two questions:1)how do species’temperature niche breadth and precipitation niche breadth influence specimen number?2)which trait is most associated with bird specimen number?The associations between bird specimen number and explanatory variables were examined using ordinary least squares,generalized linear models,phylogenetic generalized linear mixed models,and multiple *** results showed that Muscicapidae was the family with the highest specimen number,and Passeriformes was the order with the highest specimen *** specimen number significantly increased with larger temperature niche breadth and precipitation niche *** number was also positively associated with geographic range size,habitat specificity,hunting vulnerability and clutch size,but negatively associated with body *** findings suggest that future bird specimen collection should pay more attention to birds with limited ecological niches,large body sizes,and small clutch *** research enhances the use of bird specimen data to study and preserve biodiversity.

关键词： Biodiversity conservation Biological specimens Bird traits Scientific collection Specimen number Temperature and precipitation

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Supplementation of alanine improves biomass accumulation and lipid production of Chlorella pyrenoidosa by increasing the respiratory and metabolic processes

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Journal of Oceanology and Limnology 2024年第2期42卷 570-579页

作者： Yongfu LI Tianze ZHAO Wei SUN Ruiwen GAO Guangyuan MA Jiangsu Province Engineering Research Center for Marine Bioresources Sustainable Utilization Key Laboratory of Marine Hazards ForecastingMinistry of Natural ResourcesHohai UniversityNanjing 210098China College of Oceanography Hohai UniversityNanjing 210098China Jiangsu Innovation Center of Marine Bioresources Jiangsu Coast Development Group Co.Ltd.Nanjing 210019China

The function of exogenous alanine(Ala)in regulating biomass accumulation,lipid production,photosynthesis,and respiration in Chlorella pyrenoidosa was *** shows that the supplementation of Ala increased *** biomass and lipid production in an 8-d batch *** concentration of 10 mmol/L of Ala was optimum and increased the microalgal cell biomass and lipid content by 39.3%and 21.4%,respectively,compared with that in the control(0-mmol/L Ala).Ala supplementation reduced photosynthetic activity while boosting respiratory activity and pyruvate levels,indicating that *** used exogenous Ala for biomass accumulation through the respiratory metabolic *** accelerated respiratory metabolism due to Ala supplementation elevated the substrate pool and improved the lipogenic gene expression,promoting lipid production at *** study provided a novel method for increasing biomass accumulation and lipid production and elucidated the role of Ala in regulating lipid production.

关键词： alanine Chlorella pyrenoidosa lipid respiration lipogenic gene

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A deep learning interatomic potential suitable for simulating radiation damage in bulk tungsten

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Tungsten 2024年第2期6卷 304-322页

作者： Chang-Jie Ding Ya-Wei Lei Xiao-Yang Wang Xiao-Lin Li Xiang-Yan Li Yan-Ge Zhang Yi-Chun Xu Chang-Song Liu Xue-Bang Wu key laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China Science island University of Science and Technology of ChinaHefei 230026China laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China

So far, it has been a challenge for existing interatomic potentials to accurately describe a wide range of physical properties and maintain reasonable efficiency. In this work, we develop an interatomic potential for simulating radiation damage in body-centered cubic tungsten by employing deep potential, a neural network-based deep learning model for representing the potential energy surface. The resulting potential predicts a variety of physical properties consistent with first-principles calculations, including phonon spectrum, thermal expansion, generalized stacking fault energies, energetics of free surfaces, point defects, vacancy clusters, and prismatic dislocation loops. Specifically, we investigated the elasticity-related properties of prismatic dislocation loops, i.e., their dipole tensors, relaxation volumes, and elastic interaction energies. This potential is found to predict the maximal elastic interaction energy between two 1/2 loops better than previous potentials, with a relative error of only 7.6%. The predicted threshold displacement energies are in reasonable agreement with experimental results, with an average of 128 eV. The efficiency of the present potential is also comparable to the tabulated gaussian approximation potentials and modified embedded atom method potentials, meanwhile, can be further accelerated by graphical processing units. Extensive benchmark tests indicate that this potential has a relatively good balance between accuracy, transferability, and efficiency.

关键词： Machine learning Deep learning Interatomic potential Radiation damage Tungsten

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Observation of Giant Topological Hall Effect in Room-Temperature Ferromagnet Cr_(0.82)Te

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Chinese Physics Letters 2024年第6期41卷 128-140页

作者：苗伟婷甄伟立陆振王恒宁王杰牛群田明亮 Anhui key laboratory of Low-energy Quantum Materials and Devices High Magnetic Field LaboratoryHFIPSChinese Academy of SciencesHefei 230031China Science island Branch Graduate School of University of Science and Technology of ChinaHefei 230026China School of Physics and Optoelectronic Engineering Anhui UniversityHefei 230601China

Novel magnetic materials with non-trivial magnetic structures have led to exotic magnetic transport properties and significantly promoted the development of spintronics in recent *** them is the Crx Tey family,the magnetism of which can persist above room temperature,thus providing an ideal system for potential spintronic *** we report the synthesis of a new compound,Cr_(0.82)Te,which demonstrates a record-high topological Hall effect at room temperature in this ***_(0.82)Te displays soft ferromagnetism below the Curie temperature of 340 *** magnetic measurement shows an obvious magneto-crystalline anisotropy with the easy axis located in the ab *** anomalous Hall effect can be well explained by a dominating skew scattering ***,after removing the normal Hall effect and anomalous Hall effect,a topological Hall effect can be observed up to 300 K and reaches up to 1.14μΩ·cm at 10 K,which is superior to most topological magnetic structural *** giant topological Hall effect possibly originates from the noncoplanar spin configuration during the spin flop *** work extends a new Cr_(x)Te_(y) system with topological non-trivial magnetic structure and broad prospects for spintronics applications in the future.

关键词： mechanism process topological

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Pressure-induced magnetic phase and structural transition in SmSb2

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Chinese Physics B 2024年第6期33卷 484-489页

作者：李涛王舒阳陈绪亮陈春华房勇杨昭荣 Science island Branch of Graduate School University of Science and Technology of China Anhui key laboratory of Low-Energy Quantum Materials and Devices High Magnetic Field LaboratoryHFIPS Chinese Academy of Sciences Jiangsu laboratory of Advanced Functional Materials Department of Physics Changshu Institute of Technology Institutes of Physical Science and Information Technology Anhui University Collaborative Innovation Center of Advanced Microstructures

Motivated by the recent discovery of unconventional superconductivity around a magnetic quantum critical point in pressurized CeSb2,here we present a high-pressure study of an isostructural antiferromagnetic（AFM） SmSb2through electrical transport and synchrotron x-ray diffraction *** PC～2.5 GPa,we found a pressure-induced magnetic phase transition accompanied by a Cmca→P4/nmm structural phase *** the pristine AFM phase below PC,the AFM transition temperature of SmSb2is insensitive to pressure;in the emergent magnetic phase above PC,however,the magnetic critical temperature increases rapidly with increasing *** addition,at ambient pressure,the magnetoresistivity（MR） of SmSb2increases suddenly upon cooling below the AFM transition temperature and presents linear nonsaturating behavior under high field at 2 *** increasing pressure above PC,the MR behavior remains similar to that observed at ambient pressure,both in terms of temperature-and field-dependent *** leads us to argue an AFM-like state for SmSb2above *** the investigated pressure of up to 45.3 GPa and the temperature of down to 1.8 K,we found no signature of superconductivity in SmSb2.

关键词： high pressure antiferromagnet magnetoresistivity structural transition

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Experimental investigation of engineered geopolymer composite for structural strengthening against blast loads

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Defence Technology（防务技术） 2024年第2期32卷 496-509页

作者： Shan Liu Chunyuan Liu Yifei Hao Yi Zhang Li Chen Zhan Li key laboratory of coast Civil Structure Safety of Ministry of Education Tianjin UniversityTianjin 300072China Tianjin key laboratory of Prefabricated Buildings and Intelligent Construction Hebei University of TechnologyTianjin 300400China Institute of Defense Engineering AMSPLABeijing 100850China Engineering Research Center of Safety and Protection of Explosion&Impact of Ministry of Education Southeast UniversityNanjing 211189JiangsuChina State key laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of the PLANanjing 210007JiangsuChina

The recent increase in blast/bombing incidents all over the world has pushed the development of effective strengthening approaches to enhance the blast resistance of existing civil *** geopolymer composite(EGC)is a promising material featured by eco-friendly,fast-setting and strain-hardening characteristics for emergent strengthening and ***,the fiber optimization for preparing EGC and its protective effect on structural elements under blast scenarios are *** this study,laboratory tests were firstly conducted to evaluate the effects of fiber types on the properties of EGC in terms of workability,dry shrinkage,and mechanical properties in compression,tension and *** experimental results showed that EGC containing PE fiber exhibited suitable workability,acceptable dry shrinkage and superior mechanical properties compared with other types of *** that,a series of field tests were carried out to evaluate the effectiveness of EGC retrofitting layer on the enhancement of blast performance of typical *** tests include autoclaved aerated concrete(AAC)masonry walls subjected to vented gas explosion,reinforced AAC panels subjected to TNT explosion and plain concrete slabs subjected to contact *** was found that EGC could effectively enhance the blast resistance of structural elements in different *** AAC masonry walls and panels,with the existence of EGC,the integrity of specimens could be maintained,and their deflections and damage were significantly *** plain concrete slabs,the EGC overlay could reduce the diameter and depth of the crater and spallation of specimens.

关键词： Engineered geopolymer composites Fiber optimization Strengthening material Blast resistance Masonry wall Reinforced AAC panel Plain concrete slab

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