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^(177)Lu玻璃微球反应堆辐照制备技术研究
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作者 高靖 李波 +4 位作者 张劲松 罗宁 胡映江 廖瑜浩 彭楚乔 《核动力工程》 北大核心 2026年第1期268-273,共6页
^(177)Lu有着优良的核特性,是近些年关注度最高的诊疗一体化核素之一,其临床应用前景十分广阔,是非常有潜力的放射性微球核素。相比其他基体的微球,玻璃微球具有无生物毒性、释放率低等优良性质。本工作基于火焰漂浮的方法,通过火焰烧... ^(177)Lu有着优良的核特性,是近些年关注度最高的诊疗一体化核素之一,其临床应用前景十分广阔,是非常有潜力的放射性微球核素。相比其他基体的微球,玻璃微球具有无生物毒性、释放率低等优良性质。本工作基于火焰漂浮的方法,通过火焰烧制镥玻璃、研磨筛分、火焰成球等过程,制备出粒径为20~40μm的镥玻璃微球冷球,再经过反应堆辐照后(热中子注量率为2.0×10^(14) cm^(-2)·s^(-1)),产生核反应176Lu(n,γ)^(177)Lu,成功制备出^(177)Lu玻璃微球。所制备的^(177)Lu玻璃微球形态规则,18 d内释放率低于0.01%,核纯度大于99.9%,比活度7.5 Ci/g(1 Ci=3.7×10^(10)Bq),密度3.05 g/cm^(3),各项指标满足应用要求,为后续诊断治疗提供了支撑。 展开更多
关键词 诊疗一体化 反应堆辐照 ^(177)lu玻璃微球
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^(177)Lu标记多肽类放射性药物研究进展
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作者 徐千龙 李凤林 +2 位作者 冯荷娟 史豪杰 唐显 《辐射研究与辐射工艺学报》 2026年第1期12-32,共21页
^(177)Lu具有优良的物理特性,而多肽具有分子量小、生物相容性好以及合成简便、易于修饰的优良性质,使得以^(177)Lu-DOTATATE为代表的^(177)Lu标记多肽类放射性药物在肿瘤治疗研究中展示出良好的疗效,引发了科研人员对此类药物的研究热... ^(177)Lu具有优良的物理特性,而多肽具有分子量小、生物相容性好以及合成简便、易于修饰的优良性质,使得以^(177)Lu-DOTATATE为代表的^(177)Lu标记多肽类放射性药物在肿瘤治疗研究中展示出良好的疗效,引发了科研人员对此类药物的研究热潮。多聚化、双靶向设计以及血液半衰期延长修饰等策略的组合应用,是提高靶向多肽肿瘤滞留的关键技术路径。本文对近年来研究较多的^(177)Lu标记多肽类放射性药物的靶点、多肽分子的修饰策略、^(177)Lu标记多肽类放射性药物的临床前及临床研究数据等进行综述,并对该类药物的优缺点、发展趋势等进行了对比分析。结果表明,该类药物拥有较好的安全性和治疗效果,具有广阔的应用前景。 展开更多
关键词 ^(177)lu 多肽 放射性药物
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深圳地区Lu(a-b-)表型筛查及Lutheran血型系统相关基因人群多态性比较研究
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作者 刘通 吴凡 +2 位作者 孙丽艳 邱进 梁爽 《中国输血杂志》 2026年第2期217-223,共7页
目的 调查深圳地区Lu(a-b-)稀有血型的分布频率及其分子机制,比较深圳汉族、印度人群及新疆维吾尔族人群Lutheran血型系统编码基因LU及In(Lu)表型相关基因KLF1的多态性。方法 采用血清学方法对深圳地区无偿献血者进行Lu(a-b-)表型筛查;... 目的 调查深圳地区Lu(a-b-)稀有血型的分布频率及其分子机制,比较深圳汉族、印度人群及新疆维吾尔族人群Lutheran血型系统编码基因LU及In(Lu)表型相关基因KLF1的多态性。方法 采用血清学方法对深圳地区无偿献血者进行Lu(a-b-)表型筛查;利用三代测序技术对Lu(a-b-)表型标本及深圳汉族、印度人群与新疆维吾尔族人群标本进行LU与KLF1基因全长测序,分析基因单倍型频率。结果 在深圳地区14 367例献血者中共筛选出10例Lu(a-b-)表型个体,频率约为0.07%。其中仅2例检出LU基因编码区突变,而所有个体均检出KLF1基因编码区杂合突变。LU与KLF1基因突变频率最高的人群分别是新疆维吾尔族和深圳汉族。结论 深圳地区Lu(a-b-)表型均为In(Lu)表型,其形成机制主要与KLF1基因突变相关;LU和KLF1基因在深圳汉族、印度人群及维吾尔族人群中呈现显著多态性。 展开更多
关键词 lutheran血型系统 三代测序 lu基因 KLF1基因 多态性
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Frailty as a risk factor for hospitalization and mortality in older adults admitted to a chronic heart failure hospital program before and during the COVID-19 pandemic
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作者 Jhovana Carhuallanqui-Bastidas Eleazar Guino Mejía-Sánchez +4 位作者 Willy Ramos María Luisa Huamán-Severino JoséLuis Carhuallanqui-Bastidas Jhon Alex Zeladita-Huaman Laryn Smith 《Journal of Geriatric Cardiology》 2026年第1期9-16,共8页
Objective To determine whether frailty is a risk factor for hospitalization and mortality in older adults enrolled in the "Chronic Heart Failure Program" at a hospital in Lima, Peru, between 2018–2021.Metho... Objective To determine whether frailty is a risk factor for hospitalization and mortality in older adults enrolled in the "Chronic Heart Failure Program" at a hospital in Lima, Peru, between 2018–2021.Methods This was an ambispective cohort study. A total of 85 older adults participating in the Chronic Heart Failure Program at Guillermo Almenara National Hospital were included. Each had an initial frailty assessment, forming two cohorts: frail and non-frail older adults. Medical records were reviewed, and patients were followed for one year to track events of interest(hospitalization and mortality). Overall survival and risk factors for hospitalization and death were determined.Results During follow-up, 15.3% of the older adults died, and frailty was identified in 58.8% of the patients. Overall survival using the Kaplan-Meier method was 96.5% at 3 months after entering the Chronic Heart Failure Program;92.9% at 6 months;and85.9% at one year. Multivariate analysis using Poisson regression found that frailty was not a risk factor for hospitalization(a RR =0.92;95% CI: 0.42–2.03). Survival analysis using the Cox proportional hazards model showed that frailty was also not a risk factor for mortality after one year of follow-up(a HR = 1.32;95% CI: 0.27–6.53).Conclusions Our research does not confirm frailty as a risk factor for hospitalization or mortality in older adults enrolled in the“Chronic Heart Failure Program” after one year of follow-up. 展开更多
关键词 FRAILTY HOSPITALIZATION older adults chronic heart failure medical records reviewed MORTALITY frailty assessment ambispective cohort study
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砂泥岩互层的水平井电阻率各向异性校正方法研究——以Lu9井区白垩系呼图壁河组应用为例
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作者 高宇慧 谢俊杰 +1 位作者 艾林 陈冲 《新疆地质》 2025年第4期879-883,共5页
Lu9井区白垩系呼图壁河组油藏是陆梁油田的主力油藏,复算探明石油地质储量较大。砂泥岩薄互层的水平井相对于直井由于储层变化快,单个砂体受地层各向异性的影响明显大于直井,这给水平井的测井解释造成一定困难。本次研究主要通过水平井... Lu9井区白垩系呼图壁河组油藏是陆梁油田的主力油藏,复算探明石油地质储量较大。砂泥岩薄互层的水平井相对于直井由于储层变化快,单个砂体受地层各向异性的影响明显大于直井,这给水平井的测井解释造成一定困难。本次研究主要通过水平井测井电阻率各向异性系数对测井视电阻率影响的数值进行模拟计算,分析砂泥岩薄互层的“相对电阻率各向异性”数值模拟结果,对水平井双侧向测井视电阻率进行校正,得到水平井有效储层受模型约束的相对电阻率各向异性系数的数据体,计算出真实的水平电阻率。经水平井相对电阻率各向异性校正评价后,水平井油层的钻遇率达90%以上。为Lu9井区白垩系呼图壁河组油藏的开发调整工作及规模化应用指明了方向。 展开更多
关键词 砂泥岩互层 水平井 测井资料 电阻率各向异性 方法研究 lu9井区
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胶东栖霞闪长玢岩脉中花岗岩捕虏体地球化学、锆石U-Pb年龄、Lu-Hf同位素研究及地质意义
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作者 于晓卫 任天龙 +7 位作者 程蓉蓉 王来明 刘汉栋 张学松 何铁良 王英鹏 杨仕鹏 单伟 《岩石矿物学杂志》 北大核心 2025年第1期1-23,共23页
胶东地区晚侏罗世玲珑期花岗岩主要出露于招远、莱州、文登、乳山等地区,主要包括玲珑岩体和鹊山-昆嵛山岩体,而两者之间的栖霞地区主要出露太古宙TTG类岩石。本次在栖霞地区上曲家村闪长玢岩脉(围岩为TTG类岩石)中发现较多中粒二长花... 胶东地区晚侏罗世玲珑期花岗岩主要出露于招远、莱州、文登、乳山等地区,主要包括玲珑岩体和鹊山-昆嵛山岩体,而两者之间的栖霞地区主要出露太古宙TTG类岩石。本次在栖霞地区上曲家村闪长玢岩脉(围岩为TTG类岩石)中发现较多中粒二长花岗岩捕虏体,锆石SHRIMP U-Pb年龄为161.0±2.2 Ma,^(176)Hf/^(177)Hf值为0.281929~0.281971,εHf(t)值为-26.39~-24.77,亏损地幔二阶段模式年龄t_(DM2)为2871~2773 Ma,岩石地球化学特征显示,二长花岗岩捕虏体具有富钾、高铝、贫镁和铁的特征,为过铝质高钾钙碱性岩石,亏损重稀土元素,轻重稀土元素分馏明显,(La/Yb)_(N)值变化在28.11~78.50之间,有明显的Eu正异常(Eu/Eu^(*)=1.16~1.77),大离子亲石元素Rb、K、Ba、Sr相对富集。其同位素年代学、岩相学、岩石地球化学特征与玲珑岩体、鹊山-昆嵛山岩体基本一致,是在古太平洋板块的运动背景下,扬子板块与华北板块陆陆碰撞加厚的地壳部分熔融的结果,物源区以TTG类岩石为主,本文认为这些二长花岗岩捕虏体归属为玲珑期花岗岩。结合区域重力异常解译,认为栖霞地区TTG类岩石下部有隐伏的玲珑期花岗岩体,推测范围西起陡崖断裂,东至桃村断裂,南至胶莱盆地北缘,北至臧家庄盆地南缘,玲珑岩体和鹊山-昆嵛山岩体在深部可能是连通的。 展开更多
关键词 花岗岩捕虏体 岩石地球化学 U-Pb同位素测年 lu-HF同位素 胶东栖霞
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Phases of Environmental Evolution Indicated by Primary Chemical Elements and Paleontological Records in the Upper Pleistocene-Holocene Series for the Salawusu River Valley,China 被引量:18
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作者 LI Baosheng WEN Xiaohao +5 位作者 QIU Shifan David Dian ZHANG DU Shuhuan CHEN Deniu OU Xianjiao NIU Dongfeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第4期555-565,共11页
Studies of lithology, sedimentary facies and the distribution regularity of SiO2 and Al2O3 contents and Al2O3/SiO2 ratio allow us to divide the Upper Pleistocene-Holocene Series represented by the MUanggouwan section ... Studies of lithology, sedimentary facies and the distribution regularity of SiO2 and Al2O3 contents and Al2O3/SiO2 ratio allow us to divide the Upper Pleistocene-Holocene Series represented by the MUanggouwan section in China's Salawnsu River valley into six segments: MGS1, MGS2, MGS3, MGS4, MGS5 and MGS6. The boundary ages for MGS1 (the Dishaogouwan and Dagouwan Formations), MGS2 (the upper Chengchuan Formation), MGS3 (the middle Chengchuan Formation), MGS4 (the lower Chengchuan Formation), MGS5 (most strata of the Salawusu Formation) and MGS6 (the bottom of the Salawusu Formation and the top of the Lishi Formation) correspond to those of MIS1, MIS2, MIS3, MIS4, MISS and MIS6, respectively, from deep sea sediments or continental glaciers. MGS5 can be subdivided into five subsegments (MGS5a, MGS5b, MGS5c, MGS5d and MGS5e) and the boundary ages of these subsegments correspond to those of MISSa, MISSb, MIS5c, MIS5d and MIS5e, respectively. Based on the paleoenvironment and paleoecology indicated by the primary chemical elements, fossil vertebrates, mollusks and pollen grains, we hypothesize that MGS1, MGS2, MGS3, MGS4, MGS5 and MGS6 and the subsegments of MGS5 match the corresponding stages for oxygen isotopes in the deep sea sediments and continental glaciers, and the substages of MIS5 in terms of climatic characters, further explaining the phenomena that determined the formation of the late Quaternary strata and the paleontology of the Salawusu River valley. These phenomena relate to fluctuations in the global climate (and particularly in the East Asian monsoon) during the glacial and interglacial periods. 展开更多
关键词 Salawusu River valley Upper Pleistocene-Holocene Series primary chemical elements phases of evolution paleontological records
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New host and locality records of snake intestinal nematode Kalicephalus spp in Indonesia 被引量:3
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作者 Endang Purwaningsih Mumpuni 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2011年第2期121-123,共3页
Objective:To observe three species of Kalicephalus found in three species of snake(Ophkphagus hannah,Ptyas mucosus,and Naja Sputatrix) during research on Capture Snake for Trading in Java and Snake Biodiversity in Kal... Objective:To observe three species of Kalicephalus found in three species of snake(Ophkphagus hannah,Ptyas mucosus,and Naja Sputatrix) during research on Capture Snake for Trading in Java and Snake Biodiversity in Kalimantan Islands.Methods:Specimens for light microscopy examination were fixed with warm 70%alcohol,cleared and mounted in lactophenol for wet mounting.Drawings were made with the aid of a drawing tube attached to a Nikon compound microscope.Measurements were given in micrometers(μ) as the average of findings,followed by the range in parentheses,unless otherwise stated.Results:Kalkephalus(Costatus) indicus was found from 7 Ptyas mucosus,Kalicephalus bungari from 2 Naja sputatrix and 1 Kalicephalus(Costatus) indicus and Kalicephalus assimilis found from 1 Ophiophagus hannah.The morphology and measurement of three species of Kalicephalus found in this study were close to those described before.Conclusions:New finding of host of Kalicephalus(Costalus) indicus and Kalicephalus bungari was a snake species of Naja sputatrix.New records of locality were Kalimantan island as the new locality of Kalicephalus assimilis,and Java island was new locality of Kalicephalus(Costatus) indicus. 展开更多
关键词 Strongyloidea Kalicephalus Snakes NEW record Indonesia INTESTINAL NEMATODE NEW host
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New Records of Genus Oncocephalus (Hemiptera: Reduviidae: Stenopodainae) from Cambodia
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作者 CONSTANT Jerome 刘霞 +1 位作者 CONSTANT Jerome 彩万志 《Entomotaxonomia》 CSCD 北大核心 2009年第2期127-128,共2页
The stenopodaine genus Oncocephalus Klug, 1850 and two species of this genus, O. breviscutum Reuter, 1882 and O. pudicus Hsiao, are recorded from Cambodia for the first time.
关键词 HEMIPTERA REDUVIIDAE Oncocephalus new record Cambodia
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Three new records of Lumbrineridae Schmarda,1861(Annelida:Polychaeta)species in China 被引量:2
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作者 蔡文倩 李新正 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第6期1297-1301,共5页
Three species of Lumbrineridae, Helmutnerisflabellicola (Fage, 1936), Lurnbrinerides dayi Perkins, 1979, and Ninoe japonica Imajima & Higuchi, 1975, are reported from the material collected between 1959 and 1994 fr... Three species of Lumbrineridae, Helmutnerisflabellicola (Fage, 1936), Lurnbrinerides dayi Perkins, 1979, and Ninoe japonica Imajima & Higuchi, 1975, are reported from the material collected between 1959 and 1994 from the Yellow Sea, East China Sea, and South China Sea. These species are not previously recorded from Chinese waters. Systematic descriptions and morphological illustrations of the species are provided in this paper. 展开更多
关键词 POLYCHAETA lumbrineridae new records Chinese waters Helmutnerisflabellicola lumbrinerisdayi Ninoe japonica
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Assembly, Accretion and Break-up of the Paleo-Mesoproterozoic Columbia(Nuna) Supercontinent: Records in the North China Craton 被引量:5
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作者 ZHAO Guochun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期50-,共1页
Columbia(Nuna)is a Paleo-Mesoproterozoic supercontinent that was assembled during global 2.0–1.8Ga collisional events,underwent long-lived,subductionrelated accretion at key continental margins in the period
关键词 Ga Accretion and Break-up of the Paleo-Mesoproterozoic Columbia Assembly Nuna records in the North China Craton SUPERCONTINENT
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P507浸渍的聚苯乙烯与聚丙烯酸酯树脂分离Yb/Lu的对比研究
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作者 樊锡胜 马国权 +6 位作者 彭海岳 高靖 李飞泽 兰图 廖家莉 杨远友 刘宁 《原子能科学技术》 北大核心 2025年第1期24-34,共11页
^(177)Lu特别是无载体(NCA)177Lu在全球范围内的稳定供应问题变得尤为突出。目前,国内用于NCA^(177)Lu生产的LN2树脂有国产和也有进口产品,尽管二者高度相似,但两种LN2树脂的NCA^(177)Lu分离性能是否存在差异仍未形成统一认识,其最佳分... ^(177)Lu特别是无载体(NCA)177Lu在全球范围内的稳定供应问题变得尤为突出。目前,国内用于NCA^(177)Lu生产的LN2树脂有国产和也有进口产品,尽管二者高度相似,但两种LN2树脂的NCA^(177)Lu分离性能是否存在差异仍未形成统一认识,其最佳分离工艺流程也需要进一步优化。为此,本文开展了两种树脂的对比实验。通过多种表征手段对国产和进口LN2树脂的结构和组分等进行了系统分析,在此基础上通过静态吸附实验考察了两种材料对Yb/Lu的吸附性能差异,随后开展了二者动态柱分离Yb/Lu的对比研究,探讨了不同淋洗条件对NCA^(177)Lu分离性能的影响。此外还通过模拟工况下的分离实验研究,为每种树脂优化出了最佳淋洗方案。结果表明,国产与进口树脂的载体分别为聚苯乙烯和聚丙烯酸酯,前者具有更高的萃取剂负载量(质量分数为30.6%),Yb^(3+)和Lu^(3+)静态吸附量更高,但过高的负载量堵塞了树脂孔道,使其在动态柱实验中无法实现Yb/Lu的有效分离,带来了诸如分离度低、淋洗体积大等问题。与文献报道一致的是,进口LN2树脂的分离性能优异,在相对简单的条件下便可实现良好的分离(R_(S)=1.8)。 展开更多
关键词 负载量 浸渍树脂 Yb/lu分离 ^(177)lu
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Hyperledger Fabric Blockchain: Secure and Efficient Solution for Electronic Health Records 被引量:2
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作者 Mueen Uddin M.S.Memon +4 位作者 Irfana Memon Imtiaz Ali Jamshed Memon Maha Abdelhaq Raed Alsaqour 《Computers, Materials & Continua》 SCIE EI 2021年第8期2377-2397,共21页
Background:Electronic Health Record(EHR)systems are used as an efficient and effective technique for sharing patient’s health records among different hospitals and various other key stakeholders of the healthcare ind... Background:Electronic Health Record(EHR)systems are used as an efficient and effective technique for sharing patient’s health records among different hospitals and various other key stakeholders of the healthcare industry to achieve better diagnosis and treatment of patients globally.However,the existing EHR systems mostly lack in providing appropriate security,entrusted access control and handling privacy and secrecy issues and challenges in current hospital infrastructures.Objective:To solve this delicate problem,we propose a Blockchain-enabled Hyperledger Fabric Architecture for different EHR systems.Methodology:In our EHR blockchain system,Peer nodes from various organizations(stakeholders)create a ledger network,where channels are created to enable secure and private communication between different stakeholders on the ledger network.Individual patients and other stakeholders are identified and registered on the network by unique digital certificates issued by membership service provider(MSP)component of the fabric architecture.Results:We created and implemented different Chaincodes to handle the business logic for executing separate EHR transactions on the network.The proposed fabric architecture provides a secure,transparent and immutable mechanism to store,share and exchange EHRs in a peer-to-peer network of different healthcare stakeholders.It ensures interoperability,scalability and availability in adapting the existing EHRs for strengthening and providing an effective and secure method to integrate and manage patient records among medical institutions in the healthcare ecosystem. 展开更多
关键词 Electronic health records blockchain hyperledger fabric patient data privacy private permissioned blockchain healthcare ecosystem
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The European Source of Firearm Knowledge in Bing lu (Records of Military Art)
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作者 Yin Xiaodong Liu Shuo Yu Yueyuan 《Chinese Annals of History of Science and Technology》 2017年第2期1-17,共17页
European firearms entered China from the sixteenth century and played a significant role in the warfare of the Ming and Qing dynasties.Some Chinese military books,which include contents on European firearms,appeared i... European firearms entered China from the sixteenth century and played a significant role in the warfare of the Ming and Qing dynasties.Some Chinese military books,which include contents on European firearms,appeared in the early seventeenth century and helped to expand the weapons’influence.Certain parts in these books concerning European artilleries are highly similar,indicating that they might have been extracted from a mutual source.Bing lu兵錄(Records of military art)is a typical example of such Chinese military treatises.Its illustrations and data demonstrate that Pratica manuale di arteglieria written by Luys Collado in 1586 is an important source of the Western knowledge in certain chapters of Bing lu. 展开更多
关键词 FIREARM BING lu(records of MILITARY art) EUROPEAN source Pratica manuale di arteglieria.
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激光微区Lu-Hf定年技术原理和地质应用
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作者 吴石头 王浩 +2 位作者 杨岳衡 杨进辉 吴福元 《地质学报》 北大核心 2025年第6期1865-1887,共23页
同位素地质年代学是地球科学研究中的重要研究内容。Lu-Hf定年体系是基于^(176)Lu-^(176)Hf放射性衰变的地质年代测定方法,在高级变质岩、基性—基性岩、磷酸岩定年等方面发挥着重要作用。近年来,随着串级质谱技术的突破性进展,发现活... 同位素地质年代学是地球科学研究中的重要研究内容。Lu-Hf定年体系是基于^(176)Lu-^(176)Hf放射性衰变的地质年代测定方法,在高级变质岩、基性—基性岩、磷酸岩定年等方面发挥着重要作用。近年来,随着串级质谱技术的突破性进展,发现活性气体氨气与Lu,Yb,Hf具有差异性反应,通过测定高质量Hf反应产物(^(176)Hf(^(14)N^(1)H)(^(14)N^(1)H2)(^(14)N^(1)H3)3,相对于^(176)Hf质量数增加82),实现了^(176)Hf与^(176)Lu和^(176)Yb的在线分离。与激光剥蚀系统联用实现了原位微区Lu-Hf定年。当前,这一技术在分析仪器、碰撞反应机理、校准方法、不确定度评估和标准物质研制等方面取得了显著进展,并在地质学领域获得了广泛应用。本文将系统阐述激光微区Lu-Hf定年体系的原理,回顾其发展历程及相关地质应用。从仪器设备、反应气体、校准方法、软件开发、不确定度评估、标准物质研发等维度,全面总结该技术的关键性突破。目前该技术已在变质岩、基性岩、沉积岩、矿床及地外样品等研究领域取得应用成果。本文系统总结了这些应用案例,深入分析Lu-Hf体系的优势及微区分析的重要意义。基于当前研究现状,本文探讨了该技术面临的主要挑战,并对其潜在地质领域的应用进行展望。 展开更多
关键词 激光微区lu-Hf定年 串级质谱仪 lu矿物 石榴子石lu-Hf定年 稀土矿定年
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电沉积法分离Yb/Lu的条件研究
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作者 董昊林 梁积新 +3 位作者 成悦 赵婧妍 吴宇轩 唐显 《中国无机分析化学》 北大核心 2025年第11期1706-1715,共10页
无载体^(177)Lu在靶向放射性核素治疗领域展现了良好的应用前景。无载体^(177)Lu制备的关键技术是靶材^(176)Yb与目标核素^(177)Lu的分离。为优化高效分离^(176)Yb与^(177)Lu的工艺流程,基于理论产额计算结果,进行了电沉积法分离Yb/Lu... 无载体^(177)Lu在靶向放射性核素治疗领域展现了良好的应用前景。无载体^(177)Lu制备的关键技术是靶材^(176)Yb与目标核素^(177)Lu的分离。为优化高效分离^(176)Yb与^(177)Lu的工艺流程,基于理论产额计算结果,进行了电沉积法分离Yb/Lu的条件研究,建立了电沉积法分离无载体^(177)Lu的两种络合剂体系。选用Hg作为阴极,通过两次电沉积将水溶液中的Yb还原并沉积到Hg相中,将Lu留在溶液中。采用控制变量法,依次考察络合剂种类及浓度、电压、溶液pH值、温度、电沉积时间以及Hg阴极体积对Yb与Lu分离效果的影响,对实验参数进行了优化。实验表明,在柠檬酸钠体系中,经过两次电沉积后Lu的总回收率为99.99%,Yb去除率达到90.85%,Yb去污系数DF=10.9。在α-羟基异丁酸(α-HIBA)体系中,两次电沉积后Lu的总回收率为99.99%,Yb去除率达到98.05%,Yb去污系数DF=47.8。在电沉积结束后可将Hg阴极中96.02%的Yb回收到水溶液中,经过沉淀和煅烧可实现再利用。建立的Yb/Lu电化学分离工艺流程,在2 h内可有效降低溶液中的Yb含量,解决高浓度Yb对色谱分离柱的过载问题,有望应用于无载体^(177)Lu的制备。 展开更多
关键词 YB 无载体^(177)lu 电沉积 分离
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The influence of pressure waves in tidal gravity records 被引量:1
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作者 Bernard Ducarme 《Geodesy and Geodynamics》 CSCD 2023年第1期15-25,共11页
For the reduction of atmospheric effects,observed gravity has initially been corrected by using the computed barometric admittance k of the in situ measured pressure,expressed in nms-2/hPa units and estimated by least... For the reduction of atmospheric effects,observed gravity has initially been corrected by using the computed barometric admittance k of the in situ measured pressure,expressed in nms-2/hPa units and estimated by least squares method.However,the local pressure changes alone cannot account for the atmospheric mass attraction and loading when the coherent pressure field exceeds a specific size,i.e.,with increasing periodicities.To overcome this difficulty,it is necessary to compute the total atmospheric effect at each station using the global pressure field.However,the direct subtraction of the total gravity effect,provided by the models of pressure correction,is not yet satisfactory for S2 and other tidal components,such as K2 and P1,which include solar heating pressure tides.This paper identifies the origin of the problem and presents strategies to obtain a satisfactory solution.First,we set up a difference vector between the tidal factors of M2 and S2 after correction of the pressure and ocean tides effects.This vector,hereafter denoted as RES,presents the advantage of being practically insensitive to calibration errors.The minimum discrepancy between the tidal parameters of M2 and S2 corresponds to the minimum of the RES vector norm d.Secondly we adopt the hybrid pressure correction method,separating the local and the global pressure contribution of the models and replacing the local contribution by the pressure measured at the station multiplied by an admittance kATM.We tested this procedure on 8 stations from the IGETS superconducting gravimeters network(former GGP network).For stations at an altitude lower than 1000 m,the value of dopt is always smaller than0.0005.The discrepancy between the tidal parameters of the M2 and S2 waves is always lower than0.05% on the amplitude factors and 0.025° on the phases.For these stations,a correlation exists between the altitude and the value kopt.The results at the three Central European stations Conrad,Pecny and Vienna are in excellent agreement(0.05%) with the DDW99NH model for all the main tidal waves. 展开更多
关键词 Atmospheric pressure waves Atmospheric pressure correction in tidal records Atmospheric pressure models ERA5 and MERRA-2
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南阿尔金木纳布拉克地区巴什库尔干岩群变质岩的锆石U-Pb定年和Lu-Hf同位素特征及其地质意义 被引量:1
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作者 解添合 曹玉亭 +5 位作者 刘良 马拓 王超 康磊 盖永升 宋里豪 《岩石学报》 SCIE EI CAS 北大核心 2025年第1期198-214,共17页
南阿尔金木纳布拉克地区原划为长城纪巴什库尔干岩群中陆续识别出多类型高压变质岩,以及新元古代和古生代的原岩年龄信息。本文在前人研究的基础上,对木纳布拉克地区巴什库尔干岩群的中-低压浅变质岩进行详细的野外调查,并对三个不同岩... 南阿尔金木纳布拉克地区原划为长城纪巴什库尔干岩群中陆续识别出多类型高压变质岩,以及新元古代和古生代的原岩年龄信息。本文在前人研究的基础上,对木纳布拉克地区巴什库尔干岩群的中-低压浅变质岩进行详细的野外调查,并对三个不同岩组的6个样品进行了岩相学、锆石U-Pb定年和Hf同位素组成研究,以期对区内长城纪地层的构造归属划分提供更多的年代学证据。LA-ICP-MS锆石U-Pb定年测得红柳泉组钾长片麻岩和角闪片岩的原岩形成年龄分别为1459~1577Ma和<1493Ma、贝壳滩组钙质白云母片岩的原岩年龄为<956Ma,均为中-新元古代;此外钙质白云母片岩还获得499Ma的变质年龄,总体反映了以上3个样品具有阿尔金杂岩的锆石年龄信息。这3个样品的核部残留碎屑锆石的ε_(Hf)(t)值与阿尔金杂岩中各类变质岩的ε_(Hf)(t)值范围一致,且具有相似的二阶段模式年龄,代表了其原岩具有相似的物源。因此,综合年代学和Hf同位素组成分析可以推断,以上3个样品所属的地层不应再归为长城纪巴什库尔干岩群,而归到阿尔金杂岩更为合适。LA-ICP-MS锆石U-Pb定年获得扎斯勘赛河组长英质片麻岩、红柳泉组长英质糜棱岩和贝壳滩组斜长角闪岩的原岩年龄介于454~460Ma以及多期变质年龄分别为429~432Ma、400~402Ma和~376Ma。这3个样品的原岩年龄和变质年龄与中阿尔金南缘志留纪中-高压变质岩带内变质岩石原岩和变质年龄具有一致性,且构造位置上均位于木纳布拉克地区西南缘,与阿尔金杂岩以断裂相隔,由此初步推断其与中阿尔金南缘志留纪中-高压变质岩带有关。综上,本文认为南阿尔金木纳布拉克地区原划为长城纪巴什库尔干岩群中南部的贝壳滩组和红柳泉组样品为南阿尔金高压-超高压变质带的西延部分,北部的扎斯勘赛河组和红柳泉组样品为中阿尔金南缘志留纪中压-高压变质作用的产物。 展开更多
关键词 南阿尔金 木纳布拉克 阿尔金杂岩 锆石U-PB定年 锆石HF同位素
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New records of a genus and a species of Neritidae (Mollusca:Gastropoda:Cycloneritimorpha) from the South China Sea
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作者 CHEN Zhiyun ZHANG Junlong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第10期209-211,共3页
A neritid species Vittina pennata (von Born, 1778) is reported for the first time from the South China Sea. This is also the first report of this genus from Chinese waters. The specimen was collected from the Sanya ... A neritid species Vittina pennata (von Born, 1778) is reported for the first time from the South China Sea. This is also the first report of this genus from Chinese waters. The specimen was collected from the Sanya Harbor, Hainan Province, China and deposited in Marine Biological Museum, Chinese Academy of Sciences. Detailed descriptions of its shell feature are presented. Differences between this species, Vittina coromandeliana and Neritina pulligera are compared and discussed. 展开更多
关键词 GASTROPODA Neritidae Vittina Vittina pennata new record China seas
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Three New Records of Gastropoda(Mollusca) from the Nansha Islands,China
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作者 CHEN Zhiyun SHI Wei GONG Li 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第2期433-436,共4页
The Nansha Islands, China, have extremely high marine biodiversity and hundreds of mollusks have been reported there. Benthos resources investigations of the intertidal and subtidal zone around the Nansha Islands have... The Nansha Islands, China, have extremely high marine biodiversity and hundreds of mollusks have been reported there. Benthos resources investigations of the intertidal and subtidal zone around the Nansha Islands have been continuously performed for decades, and recently, dozens of new species and new records of mollusks have been reported from this area. This paper dealt with three new record species of the Gastropoda from Chinese waters: Cerithium salebrosum Sowerby II, 1855, Vexillum militare(Reeve, 1845) and Vexillum bizonale(Dautzenberg et Bouge, 1923), respectively belonging to three families: Cerithiidae Fleming, 1822, and Costellariidae Mac Donald, 1860. All specimens were collected from the Nansha Islands during the benthos resources investigations on the intertidal zone of islands and reefs in the South China Sea in recent years. Diagnosis and geographic descriptions of both genus and species, illustrations of each species were given in this contribution, and discussion of taxonomy, identification features and faunal characteristics were presented. All examined specimens were deposited in the Marine Biodiversity Collections of South China Sea, Chinese Academy of Sciences. 展开更多
关键词 GASTROPODA Cerithium salebrosum Vexillum militare Vexillum bizonale new records Nansha ISLANDS
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