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Multi-analytical characterization of Os Draconis:distinguishing authentic samples from fossilized specimens and counterfeits for improved authentication
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作者 Dong-Han Bai Lu Luo +5 位作者 Zi-Hao Zhang Zi Xing Remy Macdonald Shu-Min Chen Qiao-Chu Wang Zhi-Jie Zhang 《Traditional Medicine Research》 2026年第3期36-55,共20页
Background:Os Draconis is an important material in traditional Chinese medicine(TCM).However,its market is saturated with counterfeit products,and the limitations of current identification methods pose a serious threa... Background:Os Draconis is an important material in traditional Chinese medicine(TCM).However,its market is saturated with counterfeit products,and the limitations of current identification methods pose a serious threat to clinical effectiveness and drug safety.This study aims to establish a more accurate and comprehensive authentication system for Os Draconis.Methods:A comprehensive approach was employed to analyze authentic Os Draconis,fossilized Os Draconis,counterfeit products,and lab-prepared modern animal bones.The analytical techniques included ^(14)C dating,electron probe microanalysis(EPMA),polarized light microscopy,X-ray diffraction(XRD),inductively coupled plasma mass spectrometry(ICP-MS),and fourier-transform infrared spectroscopy(FTIR).The study focused on examining the microstructural features and micro-area elemental compositions to identify distinguishing characteristics.Results:Physical identification alone was insufficient to reliably distinguish authentic Os Draconis from its counterfeits.XRD analysis revealed that while hydroxyapatite is the main component in all samples,authentic Os Draconis also contains calcium carbonate and quartz,which were absent in counterfeit and lab-prepared samples.FTIR spectra identified the carbonate ion(CO_(3)^(2-))as a characteristic infrared marker for authentic Os Draconis.ICP-MS analysis showed that Ca and P are the major elements,with a notably high content of Lanthanum(La)among rare earth elements in authentic samples.The EPMA results demonstrated that the Ca/P ratio of authentic Os Draconis is distinct,falling between that of fossilized Os Draconis and counterfeit samples.Conclusion:This study successfully identified several precise markers,including the presence of calcium carbonate,the characteristic CO_(3)^(2-)infrared peak,a high La content,and a specific Ca/P ratio,for the accurate and rapid authentication of Os Draconis.Furthermore,the analysis of its natural porous structure,suitable pore size,and surface area suggests that Os Draconis has significant potential as a natural drug carrier. 展开更多
关键词 Os Draconis ULTRASTRUCTURE ^(14)C dating EPMA XRD ICP-MS FTIR
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Phytochemical Profile,Fatty Acid Composition,Mineral Content,andα-Amylase/α-Glucosidase Inhibitory Activities of Date Seed Extracts from Four Moroccan Varieties Grown in the Figuig Oasis
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作者 Manar Bouhchich Abdessadek Rahimi +3 位作者 Rhizlan Abdnim Amine Elbouzidi Mohamed Addi Mostafa Mimouni 《Phyton-International Journal of Experimental Botany》 2026年第2期184-203,共20页
Date palm(Phoenix dactylifera L.)seeds,often discarded as by-products during date fruit processing,represent approximately 6-20%of the fruit’s mass depending on cultivar and maturity stage.Although traditionally used... Date palm(Phoenix dactylifera L.)seeds,often discarded as by-products during date fruit processing,represent approximately 6-20%of the fruit’s mass depending on cultivar and maturity stage.Although traditionally used for producing activated charcoal and in environmental remediation,their pharmacological potential remains underexplored.This study aimed to evaluate the chemical composition,biological activity,and potential commercial value of seeds from four widely consumed Saharan cultivars(Assiane,Boufegouss,Aziza,and Majhoul)collected in the Figuig region.Soxhlet extraction was employed to obtain seed extracts,which were subsequently characterized by qualitative and quantitative phytochemical screening.The analyses revealed the presence of polyphenols,flavonoids,terpenoids,steroids,alkaloids,and other secondary metabolites.The Aziza and Boufegouss varieties were particularly rich in flavonoids(82.09-139.61 mg quercetin equivalents/100 g dry matter)and total polyphenols(69.81-1183.96 mg gallic acid equivalents/100 g dry matter).Mineral profiling confirmed the occurrence of essential trace elements,including Zn,Cu,Fe,and Co.To investigate their antidiabetic potential,in vitro assays ofα-glucosidase andα-amylase inhibition were performed.Acetone extracts demonstrated significant inhibitory activity against both enzymes,suggesting a promising role of P.dactylifera seed extracts as natural agents for the management of type 2 diabetes mellitus. 展开更多
关键词 Phoenix dactylifera L. date seeds PHYTOCHEMICALS mineral analysis Α-AMYLASE Α-GLUCOSIDASE antidiabetic potential
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Geochemical characteristics,formation age,and mechanism of the cold volcano at Muji travertine,Xinjiang
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作者 Jiaqi LIU Ziyang SHEN +6 位作者 Bin ZHANG Zhihao SUN Zeyang ZHU Chengqiao WU Liqing XU Yi DING Zhengfu GUO 《Science China Earth Sciences》 2026年第2期740-748,共9页
This study presents the first systematic investigation of the rock geochemistry,hydrogeochemistry,geochronology,and formation mechanisms of the calcareous travertine-type cold volcano at Muji,Xinjiang.The Muji cold vo... This study presents the first systematic investigation of the rock geochemistry,hydrogeochemistry,geochronology,and formation mechanisms of the calcareous travertine-type cold volcano at Muji,Xinjiang.The Muji cold volcano is composed predominantly of travertine,which exhibited light rare earth element enrichment relative to heavy rare earth elements.The δ^(13)C values range from 7.1‰ to 11.1‰,while δ^(18)O values span from -12.3‰ to -7.8‰,classifying it as hypogean travertine.CO_(2) primarily originates from carbonate rock decarbonation,with a portion derived from the mantle.Water samples collected from the crater show HCO 3-Ca and HCO 3-Ca·Mg hydrochemistry types.U-Th dating of calcite indicates the Muji cold volcano formed between approximately 6.3 and 2.7 ka BP.The morphology and distribution pattern of the cold volcanoes are primarily controlled by hydrostatic pressure and the southwest boundary fault of the Muji Basin.Hydrostatic pressure of groundwater determines the growth height of the cones.The bead-like distribution orientation of the volcanic cones and the major axis direction of the elliptical contour lines of the cones align with the strike of the southwest boundary fault of the Muji Basin,indicating significant control by this fault. 展开更多
关键词 Xinjiang Muji Calcareous travertine-type cold volcano U-Th dating Carbon-oxygen isotopes Hydrochemistry
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Metamorphic P-T-t Evolution and Tectonic Implications of High-pressure Granulites in the Qushan Islands,East China Sea
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作者 CAO Yiwen ZHOU Xiwen +1 位作者 DONG Jie DENG Xuanyu 《Acta Geologica Sinica(English Edition)》 2026年第1期69-81,共13页
Debate has persisted over whether the metamorphic basement of the Zhoushan Islands,easternmost Cathaysia Block,is Precambrian.Here,representative metamorphic rocks from the Qushan Islands were investigated using petro... Debate has persisted over whether the metamorphic basement of the Zhoushan Islands,easternmost Cathaysia Block,is Precambrian.Here,representative metamorphic rocks from the Qushan Islands were investigated using petrography,mineral chemistry,phase equilibria modeling and SHRIMP zircon U-Pb dating to constrain their metamorphic evolution and tectonic significance.Both the pelitic granulites(garnet-kyanite-perthite-biotite-quartz)and the mafic granulites(garnet-clinopyroxene-amphibole-plagioclase-quartz)reached high-pressure granulite-facies conditions of 1.2-1.4 GPa/820-900℃,and recorded three metamorphic stages along a clockwise P-T path with post-peak isothermal decompression.This trajectory indicated rapid exhumation of thickened continental crust during collisional orogeny.Metamorphic ages of 254±3 Ma,262±4 Ma and 259±3 Ma were obtained for mafic granulite,pelitic granulite and marble,respectively,and were consistent with the emplacement age of 259±4 Ma for a pegmatite vein.Detrital zircons in metasediments spanned 2706-330 Ma,which constrained the latest deposition to~330 Ma;thus represented mid-Paleozoic sediment metamorphosed during the late Paleozoic rather than Precambrian basement.We conclude that the Indosinian tectonothermal event in the Cathaysia Block had originated from late Paleozoic-early Mesozoic collisional orogeny between the South China Plate to the north and the Indochina Block to the south. 展开更多
关键词 METAMORPHISM high-pressure granulite zircon U-Pb dating Qushan Islands East China Sea Cathaysia Block
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Petrogenesis of Early Mesozoic Furong pluton in central Hunan,China and its implications for tungsten mineralization
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作者 Jian-xiong DU Jian-tang PENG +3 位作者 A-xiang HU Ta-gen DAI Meng-ying SUO Li-chao XIAHOU 《Transactions of Nonferrous Metals Society of China》 2026年第2期614-627,共14页
The Furong pluton,located in central Hunan,China,hosts numerous tungsten veins within and around the granite,which are of great economic significance.However,its petrogenesis and related mineralization are poorly cons... The Furong pluton,located in central Hunan,China,hosts numerous tungsten veins within and around the granite,which are of great economic significance.However,its petrogenesis and related mineralization are poorly constrained.In this study,we used U−Pb dating,petrological and geochemical methods to ascertain the emplacement time,classification of granitic rock,nature of the source rocks,formation mechanism,and its geodynamic implications for the Furong pluton.It is shown that the granite is precisely determined to be formed at~210 Ma,and belongs to the moderately-fractionated S-type granite.Combined with regional tectonic setting,it is concluded that the pluton was formed due to crust extension and thinning followed by plate collision and compression in South China.It is also revealed that tungsten mineralization and Indosinian granites exhibit a close temporal,spatial and genetic relationships,and further exploration of tungsten deposits within and around the granite in central Hunan,even in South China,is urgently needed. 展开更多
关键词 zircon U−Pb dating INDOSINIAN tungsten mineralization Furong pluton South China
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The centennial legacy of disturbances on sedimentation and carbon burial in an estuarine mangrove ecosystem,South China
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作者 Juan SU Yaobei LIN +5 位作者 Penghui LI Zhangcai QIN Luhua XIE Fan WANG Weiguang LI Jinghong ZHANG 《Journal of Oceanology and Limnology》 2026年第1期109-124,共16页
Both natural and human-induced disturbances affect the normal functioning and services of mangrove ecosystems.To address the consequences of intense human and climatic disturbances on sedimentation and carbon burial,s... Both natural and human-induced disturbances affect the normal functioning and services of mangrove ecosystems.To address the consequences of intense human and climatic disturbances on sedimentation and carbon burial,sediment cores from the last remaining mangrove Kandelia obovata forest and an adjacent mudflat in the densely populated and typhoon-prone Zhujiang(Pearl)River estuary of China,were analyzed using methods including^(210)Pb dating andδ^(13)C analysis.Results indicate that after damming in the 1950s,during 1960-1980,the natural establishment of K.obovata forests initiated the insitu sedimentation.As these forests matured during 1980-1990,they significantly boosted siltation in the region on mudflat.During 1990-2015,the invasion of Spartina alterniflora and land reclamation for aquaculture caused infiltration of coarse sediments and the impacts of typhoons were recorded within the K.obovata forest,while no clear typhoon record was observed on the mudflat.Since 2015,reforestation efforts with S.apetala that began in 1999 have reversed the effects of earlier deforestation.Over time,mangroves established a rapid autochthonous carbon burial that grew as the forests age,potentially surpassing the influx of allochthonous carbon due to deforestation.The reforestation also immediately improved carbon burial on the mudflat,which stabilized after a decade due to the rapid growth and high biomass of S.apetala.Overall,the K.obovata forest demonstrated a stronger sedimentation and carbon burial capabilities than the mudflat,with a surplus of 35.2 Mg C/hm^(2)in soil organic carbon stock and 1.0 Mg C/(hm^(2)·a)in burial rate.Organic matter dissolved in soil was mainly humus-like components,and mangrove inputs likely increased the degree of humification.This study offered direct evidence regarding the impact of multiple disturbances on local and regional sedimentation and carbon burial,and future management strategies. 展开更多
关键词 MANGROVE DEFORESTATION REFORESTATION allochthonous source 210Pb dating δ^(13)C
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Geochronology,geochemistry and tectonic setting of Middle Permian ophiolites in Yaduwula region,Inner Mongolia
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作者 JIANG He HAN Jie +1 位作者 ZHOU Jianbo LI Gongyu 《Global Geology》 2026年第1期31-48,共18页
The Solonker Suture records the termination of the Central Asian Orogenic Belt(CAOB),but its eastward extension beneath the Songliao Basin has not been clear.The Yaduwula ophiolite is one of the significant fragments ... The Solonker Suture records the termination of the Central Asian Orogenic Belt(CAOB),but its eastward extension beneath the Songliao Basin has not been clear.The Yaduwula ophiolite is one of the significant fragments within the Solonker Suture.LA–ICP–MS U–Pb dating of zircon grains from metamorphic basalts yield ages of 263±4 Ma and 274±3 Ma,constraining the Yaduwula ophiolite in the late Cisuralian and Guadalupian age.This might indicate that the subduction of Paleo-Asian Ocean continued until at least the Guadalupian(middle Permian).Geochemical analysis of the metamorphic basalts revealed enrichment in large ion lithophile elements(LILEs)and depletion in high field strength elements(HFSEs)and show the characteristics of a supra-subduction zone.The results provide the evidence for the closure time of the Paleo-Asian Ocean after the middle Permian and also suggest that the Yaduwula ophiolite may be considered the eastern extension of Solonker Suture.Our study provides further insights on the evolution of the southeastern Central Asian Orogenic Belt. 展开更多
关键词 Yaduwula ophiolite Solonker Suture Central Asian Orogenic Belt zircon U-Pb dating
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A Multi-Stage Pipeline for Date Fruit Processing: Integrating YOLOv11 Detection, Classification, and Automated Counting
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作者 Ali S.Alzaharani Abid Iqbal 《Computers, Materials & Continua》 2026年第1期1327-1353,共27页
In this study,an automated multimodal system for detecting,classifying,and dating fruit was developed using a two-stage YOLOv11 pipeline.In the first stage,the YOLOv11 detection model locates individual date fruits in... In this study,an automated multimodal system for detecting,classifying,and dating fruit was developed using a two-stage YOLOv11 pipeline.In the first stage,the YOLOv11 detection model locates individual date fruits in real time by drawing bounding boxes around them.These bounding boxes are subsequently passed to a YOLOv11 classification model,which analyzes cropped images and assigns class labels.An additional counting module automatically tallies the detected fruits,offering a near-instantaneous estimation of quantity.The experimental results suggest high precision and recall for detection,high classification accuracy(across 15 classes),and near-perfect counting in real time.This paper presents a multi-stage pipeline for date fruit detection,classification,and automated counting,employing YOLOv11-based models to achieve high accuracy while maintaining real-time throughput.The results demonstrated that the detection precision exceeded 90%,the classification accuracy approached 92%,and the counting module correlated closely with the manual tallies.These findings confirm the potential of reducing manual labour and enhancing operational efficiency in post-harvesting processes.Future studies will include dataset expansion,user-centric interfaces,and integration with harvesting robotics. 展开更多
关键词 Date fruit cultivation YOLOv11 precision agriculture real-time processing automated fruit counting deep learning agricultural productivity
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A comparative study on the apatite and zircon from the ore-related and-barren magmatic rocks of the Shatanjiao region,Lower Yangtze River Belt:Controlling effects for petrogenesis and Cu-Au mineralization
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作者 Yu Wang Jing-ya Cao +4 位作者 Sheng-xiong Yang Xiao-yong Yang Majid Ghasemi Siani Asghar Dolati Muhammad Hafeez 《China Geology》 2026年第1期120-135,I0015-I0022,共24页
The links between the adakitic rocks and Cu-Au mineralization have long been argued.This study investigates petrogenesis and its link to mineralization potential by a series of in-situ geochronological and geochemical... The links between the adakitic rocks and Cu-Au mineralization have long been argued.This study investigates petrogenesis and its link to mineralization potential by a series of in-situ geochronological and geochemical signatures of apatite and zircon in three ore-related intrusions and one-barren intrusion in the Middle-Lower Yangtze River Metallogenic Belt(MLYRB).Zircon U-Pb dating yield ages of 139–143 Ma and 121 Ma for the ore-related and ore-barren intrusions,respectively.The ore-related rocks have higher apatite Sr/Y(1.57–9.69),(La/Yb)_(N)(16.7–159.5),andδEu(0.45–0.74)than the ore-barren rocks of 0.57–1.02,19.3–24.1 and 0.40–0.45,respectively,indicating the former has an adakitic affinity,while the latter has a non-adakitic affinity.The ore-related rocks have enriched zircon Hf isotopes withε_(Hf)(t)values of-15.9 to-5.5 and T_(DMC)ages of 2408–1655 Ma and apatite Sr-Nd isotopes,indicating that the ore-related magmas were mainly originated from partial melting of subducted oceanic crust.The orebarren rocks have higherε_(Hf)(t)values of-6.6 to-4.6 and lower T_(DMC)ages of 1598–1469 Ma and apatite Sr-Nd isotopes,indicating a lithospheric mantle source.The ore-related rocks have higher oxygen fugacity of mean∆FMQ+2.00 and X_(F)/X_(OH)of 8.36–175 than the ore-barren rocks of mean∆FMQ+1.43 and3.72–4.96.It was inferred that magma source,water content,and oxygen fugacity emerge as critical factors governing the regional Cu-Au mineralization potential. 展开更多
关键词 Sr-Nd-Hf isotopes Zircon U-Pb dating Apatite Sr-Nd isotopes Oxygen fugacity Magma source Adakitic rocks Cu-Au mineralization Shatanjiao Orefield
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Deep geological processes of the early Middle Jurassic granitic complexes in the Songjianghe area,Jiapigou-Haigou collage zone,Northeast China:Evidence from zircon U-Pb dating,elemental geochemistry and Sr-Nd-Hf isotopes
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作者 Xinwen Zhang Jinggui Sun +2 位作者 Zuochao Lin Shu Wang Yunpeng He 《Acta Geochimica》 2025年第6期1308-1327,共20页
The deep geologic processes between the Xing’an-Mongolian Orogenic Belt and the North China Craton in the Mesozoic are crucial to reveal the magmatic and tectonic evolution and their constraints on mineralization in ... The deep geologic processes between the Xing’an-Mongolian Orogenic Belt and the North China Craton in the Mesozoic are crucial to reveal the magmatic and tectonic evolution and their constraints on mineralization in the Jiapigou-Haigou collage zone.In this paper,We have presented the geochronology,geochemistry and Sr-Nd-Hf isotopic compositions of the Middle Jurassic granitic complexes in the Songjianghe area,Jilin Province.The granitic complexes can be categorized into four groups based on their geologic characteristics,with corresponding zircon U-Pb isotope ages of 177 Ma,172 Ma,169 Ma and 168-167 Ma,respectively.These granitoids exhibit calcalkaline to high-K calc-alkaline,metaluminous to weakly peraluminous Ⅰ-type characteristics,which show relative enrichment in LILEs(Rb,Sr,Ba)and depletion in HFSEs(Nb,Zr).Geochemical analyses reveal high initial^(87)Sr/^(86)Sr ratios of 0.70633-0.70740,coupled with lowεNd(t)values ranging from−10.65 to−13.23.The zircon analyses show similarly negativeεHf(t)values ranging from−16.9 to−3.2.The integrated elemental and Hf-Sr-Nd isotopic signatures demonstrate that the primitive magmas of the four group rocks were primarily derived from partial melting of thickened Archean lower crust,with the exception of the Group Ⅳ rocks,which exhibit significant evidence of crustal contamination.The residual mineral assemblages during the magma-forming process varied from amphibole to eclogite facies.These findings indicate that magmatism in the Songjianghe region likely resulted from the accretion and delamination of the Archean crust in the collage zone during the subduction of the Paleo-Pacific Plate beneath the Eurasian continent. 展开更多
关键词 U-Pb datings Elemental geochemistry and Sr-Nd-Hf isotopes Petrogenesis Middle Jurassic granitic complexes Deep geologic processes Songjianghe area
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Neuroprotection by resveratrol-glucuronide and quercetin-glucuronide via binding to polyphenol-and glycosaminoglycan-binding sites in the laminin receptor 被引量:1
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作者 Rayudu Gopalakrishna Jennifer Aguilar +1 位作者 Emily Lee William J.Mack 《Neural Regeneration Research》 SCIE CAS 2025年第3期819-820,共2页
The dietary polyphenolic compounds resveratrol and quercetin prevent neurodegenerative diseases in experimental models;however, they reach the brain only in nanomolar concentrations in the glucuronidated and sulfated ... The dietary polyphenolic compounds resveratrol and quercetin prevent neurodegenerative diseases in experimental models;however, they reach the brain only in nanomolar concentrations in the glucuronidated and sulfated forms, and not as the aglycone parent form(Pasinetti et al.,2015). 展开更多
关键词 RESVERATROL MOLAR dated
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High-pressure Granulite-facies Metamorphism and Anatexis in Continental Collision Orogen:Evidence from the Mafic Granulite and Leucosomes in South Altun,Northwestern Qinghai-Tibet Plateau 被引量:1
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作者 GUO Jing LI Yunshuai ZHANG Jianxin 《Acta Geologica Sinica(English Edition)》 2025年第1期53-68,共16页
Deciphering high-pressure granulite-facies metamorphism and anatexis within a collisional orogeny can provide crucial constraints on geodynamic evolution and melt activity during subduction and exhumation.Combining pe... Deciphering high-pressure granulite-facies metamorphism and anatexis within a collisional orogeny can provide crucial constraints on geodynamic evolution and melt activity during subduction and exhumation.Combining petrographic observations,mineral chemistry,REE in Grt-Cpx thermobarometry,and previous work,at least four stages are suggested for the metamorphic evolution of the mafic granulites in the South Altun,including the protolith stage,the high-pressure granulite-facies stage(909-1037℃and 17.3-30 kbar),medium-pressure granulite-facies overprint(9.1-11.9 kbar and 753-816℃),and subsequent late amphibolite-greenschist-facies metamorphism.Zircon U-Pb dating shows that the mafic granulites underwent high-pressure granulite-facies metamorphism at 497.2±3.7 Ma,while the leucosome formed at 498.2±2.9 Ma.Thus,the leucosomes from the host mafic granulite may have been formed at the high-pressure granulite-facies metamorphic event.The characteristics of zircon morphology,mineral inclusions,low Th/U values,HREE enrichment,and negative Eu anomalies indicate that these zircons from the leucosome were formed from the metamorphic melts.The characteristics of whole-rock major and trace elements as well as Hf isotopic features of zircons between the leucosomes and the host mafic granulite indicate that the melt may have been generated by the partial melting of the host mafic granulite. 展开更多
关键词 ANATEXIS zircon U-Pb dating HP mafic granulite leucosome South Altun
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Decoding complexity: the need to enhance precision and streamline spatial understanding in neuroscience
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作者 Sameehan Mahajani Armita Salahi +2 位作者 Brenda Gonzalez Charlotte Nelson Frank Hsiung 《Neural Regeneration Research》 SCIE CAS 2025年第3期801-802,共2页
Neuroscience is the ultimate frontier in our quest for a comprehensive understanding of human behavior. Since its launch in 2009, the Human Connectome Project has emerged as a pioneering force, making heroic strides i... Neuroscience is the ultimate frontier in our quest for a comprehensive understanding of human behavior. Since its launch in 2009, the Human Connectome Project has emerged as a pioneering force, making heroic strides in elucidating the intricate correlation between structural information and the functioning of the human brain. 展开更多
关键词 behavior FRONTIER DATING
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Instructions for Authors of Chemical Research in Chinese Universities
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《高等学校化学学报》 北大核心 2025年第4期F0003-F0003,共1页
The journal Chemical Research in Chinese Universities is a comprehensive academic journal in the field of chemistry,published bimonthly since 1984.The journal publishes research articles,letters/communications and rev... The journal Chemical Research in Chinese Universities is a comprehensive academic journal in the field of chemistry,published bimonthly since 1984.The journal publishes research articles,letters/communications and reviews written by faculty members,researchers and postgraduates in universities,colleges and research institutes all over China and overseas.It reports the latest and the most creative results of important fundamental research in all aspects of chemistry and of developments with significant consequences across sub-disciplines.This journal is sponsored by Jilin University and mandated by the Ministry of Education of P.R.China. 展开更多
关键词 JOURNAL consequences dated
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How to Understand in-situ U-Pb Isotopic Data of Uraninite and Pitchblende?
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作者 Chunying Guo 《Journal of Earth Science》 2025年第4期1835-1841,共7页
0 INTRODUCTION Uraninite and pitchblende are the most important ore minerals in nearly all types of uranium deposits.Therefore,the U-Pb isotopic system of uraninite and pitchblende are widely used in dating uranium de... 0 INTRODUCTION Uraninite and pitchblende are the most important ore minerals in nearly all types of uranium deposits.Therefore,the U-Pb isotopic system of uraninite and pitchblende are widely used in dating uranium deposits. 展开更多
关键词 URANINITE DATING dating uranium deposits situ u pb isotopic data PITCHBLENDE ore minerals uranium deposits
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Correction:Phosphorus-caused embrittlement of SA508Gr.4N reactor pressure vessel steel and its suppression by rare-earth cerium
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作者 Yu Guo Kai Wang +1 位作者 Wen-shuai Liu Xiao-ping Zhu 《Journal of Iron and Steel Research International》 2025年第12期4530-4530,共1页
Correction to:J.Iron Steel Res.Int.https://doi.org/10.1007/s42243-025-01460-1 The publication of this article unfortunately contained mistakes.The revised and accepted dates were not correct.The corrected dates are gi... Correction to:J.Iron Steel Res.Int.https://doi.org/10.1007/s42243-025-01460-1 The publication of this article unfortunately contained mistakes.The revised and accepted dates were not correct.The corrected dates are given below. 展开更多
关键词 SUPPRESSION SA GR N corrected dates phosphorus embrittlement reactor pressure vessel steel rare earth cerium revised accepted dates
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First discovery of the Late Triassic syenite and coeval epigenetic Cu mineralization in the Jianglang Dome, eastern Tibetan Plateau, China
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作者 Yanpei Dai Yudi Zhu +4 位作者 Di Xiu Huihua Zhang Shengxian Liang Tongzhu Li Qing Zhou 《Acta Geochimica》 2025年第3期478-495,共18页
The Jianglang Dome has integral tectonostratigraphic units and contains a suite of high-grade stratiform Cu deposits.However,the formation mechanism of this dome and genetic model of Cu mineralization remain a matter ... The Jianglang Dome has integral tectonostratigraphic units and contains a suite of high-grade stratiform Cu deposits.However,the formation mechanism of this dome and genetic model of Cu mineralization remain a matter of debate.The resolution of these problems hinges on the presence of magmatic intrusions in the core.Here,we report bulk geochemical and zircon U-Pb data of a newly discovered syenite intrusion as well as chalcopyrite Re-Os dating results.We aim to explore genesis of the Jianglang Dome,genetic model of the stratiform Cu deposits,and rare metal mineralization potential of the syenite intrusion.The dated syenite sample yields an emplacement age of 207.1±2.0 Ma,which matches post-collisional extension in the Songpan-Ganze Orogen.The syenite rocks have average high(Zr+Nb+Ce+Y)concentrations of 512 ppm,10000.Ga/Al ratios of 3.97,and crystallization temperatures of 827°C,together with low Mg#values of 1.73;they fi t the A-type granitoid defi nition and a crustal origin.Chalcopyrite separates yield a Re-Os isochron age of 207.1±5.3 Ma,which markedly postdates the formation age of their orehosting rocks(the Liwu Group,ca.553 Ma).Our new age determination,together with previous chalcopyrite Re–Os isochron age of ca.151.1 Ma and sulfi de sulfur isotope(δ^(34)S_(V-CDT)=8.7‰–5.6‰)and tourmaline boron isotope(δ^(11)B=−15.47‰to−5.91‰)data,confi rms multistage epigenetic Cu mineralization related to magmatic-hydrothermal fl uids.Compared with regional ca.209–207 Ma fertile granitoids,the studied syenite intrusion shows unevolved and barren affi nities and negligible rare metal mineralization potential.Combined with residual gravity low anomalies in the core of the Jianglang Dome,which suggest a large deepseated granitic batholith,we prefer thermal doming resulting from magma-induced uplift for the nature of this dome. 展开更多
关键词 Syenite intrusion Zircon U-Pb dating Chalcopyrite Re-Os dating Epigenetic mineralization Stratiform Cu deposits Jianglang Dome
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First discovery of Cretaceous tuffs in the Zhenyuan area,southwestern Ordos Basin,China:Constraints from zircon U-Pb dating
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作者 Yin Chen Lu-lu Chen +1 位作者 Jian-guo Li Hua-lei Zhao 《China Geology》 2025年第2期457-459,I0048,I0053,共5页
1.Objective,The Cretaceous succession is characteristic of the aeolian sedimentary system in the Ordos Basin,which is the major ore-bearing layer for the sandstone-type uranium deposits.Based on the research of paleon... 1.Objective,The Cretaceous succession is characteristic of the aeolian sedimentary system in the Ordos Basin,which is the major ore-bearing layer for the sandstone-type uranium deposits.Based on the research of paleontology and magnetostratigraphy,formers believed it belonged to the Early Cretaceous(Huang YB,2010).However,the lack of intrusions or volcanic rocks for isotopic dating results in an unclear formation age for the Lower Cretaceous succession.Recently,tuffs were firstly discovered in the Luohandong Formation in the Zhenyuan area,Gansu Province,located in the southwestern Ordos Basin,China.The LA-ICP-MS zircon U-Pb dating of tuffs was carried out.The new ages can precisely constrain the depositional age of the Luohandong Formation and also provide significant indications for the study of regional volcanic activities,paleoclimate,basin evolution,and tectonic setting. 展开更多
关键词 southwestern ordos basin cretaceous tuffs cretaceous succession volcanic rocks aeolian sedimentary system la icp ms zircon u pb dating isotopic dating depositional age
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Updating the Outdated
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作者 QI YU 《China Today》 2025年第3期74-75,共2页
The ideology of being ready to make innovation and keeping abreast of the times is a defining feature of the Chinese civilization.IN several of his recent speeches President Xi Jinping stressed that the Chinese civili... The ideology of being ready to make innovation and keeping abreast of the times is a defining feature of the Chinese civilization.IN several of his recent speeches President Xi Jinping stressed that the Chinese civilization has the tradition of discarding the outdated in favor of the new and moving ahead with the times.In exploring a new philosophy that is suitable for governing China in the new era,China draws on its fine traditional culture to find ways of abolishing outdated ideas and making theoretical,practical,and institutional innovations,thus staying abreast of the time to create a better future. 展开更多
关键词 dated DATING CULTURE
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Tracing carbonate diagenesis and hydrothermal activity during the opening of the Central South Atlantic: Insights from the Santos Basin (Brazil)
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作者 Igor Figueiredo Cristiano Lana +5 位作者 Fernando F.Alkmim Marco A.Silva Maria Eugênia S.Souza Dorval C.Dias-Filho Eveline E.Zambonato Katia R.N.Mendonça 《Geoscience Frontiers》 2025年第5期245-259,共15页
The opening of the Central South Atlantic and the consequent formation of the eastern Brazilian continental margin was marked by a complex history of mafic magmatism,carbonate sedimentation,and deposition of a thick s... The opening of the Central South Atlantic and the consequent formation of the eastern Brazilian continental margin was marked by a complex history of mafic magmatism,carbonate sedimentation,and deposition of a thick salt layer.The carbonates underlying the salt layer(pre-salt carbonates)were formed in restricted lacustrine basins.Here,the timing and fluid sources of deposition,diagenetic,and hydrothermal alterations of the pre-salt carbonate rocks are defined through in-situ U-Pb dating,87Sr/86Sr,and trace element analyses of samples from the Santos Basin.The very alkaline nature of the Aptian lake(s)produced characteristically unique and widely distributed carbonate rocks such as Mg-clays with calcite spherulite and calcite crystal shrub limestones transitioning laterally and vertically into travertines formed by hydrothermal pulses during basin evolution.Hydrothermalism caused extensive replacement,dissolution,and calcite cementation.REE+Y PAAS-normalised patterns and 87Sr/86Sr ratios indicate that deposition/eo-diagenesis of the primary carbonates occurred in a lacustrine environment primarily controlled by evaporation,pH,and continental water source,with 2%–10%hydrothermal fluid input.Trace elements and Sr-isotope of travertines and burial diagenetic phases show that they are produced from a hot mixture of mafic/mantle-derived fluids and dissolution/alteration of older carbonate formations.U-Pb dating indicates that carbonate deposition occurred between 124.8±2.6 Ma and 120.0±1.6 Ma,earlier than previously proposed,followed closely by the circulation of hydrothermal fluids.Replacement and cementation ages range from 120.5±2.4 Ma to 80.4±2.4 Ma. 展开更多
关键词 PRE-SALT CARBONATE U-Pb dating Sr-isotope Trace elements LA-ICP-MS
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