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Application of Detrital Apatite U-Pb Geochronology and Trace Elements for Provenance Analysis,Insights from a Study on the Yarlung River Sand

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Journal of Earth Science 2024年第4期35卷 1118-1129页

作者： yufeng du Guangwei Li Danyang Liu Xianyan Wang Dongxu Cai Xiaolu Dong Qi Yu State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjing210023China School of Geography and Ocean Nanjing UniversityNanjing210023China

Detrital U-bearing minerals(e.g.,zircon,apatite)U-Pb ages with specific trace-element geochemistry,are frequently used in provenance *** this study,we focus on the Yarlung River drainage in South Tibet,characterized by two distinct lithologic units:The Gangdese batholith to the north(mainly granitoids)and the Tethyan Himalaya(mainly sedimentary rocks)to the south,which plays a crucial role in the erosion of the Tibetan *** constrain the provenance of the Yarlung River Basin,we performed trace-element and U-Pb age analyses of detrital apatite from the river sands of the Yarlung River and its *** findings indicate that the detrital apatite U-Pb age patterns of the north tributaries exhibit main peaks at approximately 40 and 60 Ma,consistent with the corresponding U-Pb age patterns of detrital zircon ***,their trace element casts fall mainly in the Type I granite region,also indicating the Gangdese arc-dominated ***,those of the south tributaries(∼60–20 Ma)exhibit a different age distribution from the detrital zircon U-Pb groups(∼110–150,∼500,and 1100 Ma),suggesting that the detailed apatite U-Pb signals can provide excellent constraints on the provenance of igneous and metamorphic rock sources but less so for sedimentary rock *** with previous detrital zircon data in the study area,our detrital apatite information can highlight young metamorphic events from a complex background(i.e.,Niyang and Nianchu rivers),which offers additional constraints on the provenance of the Yarlung River ***,a combination of geochemistry and geochronology of multi-detrital heavy minerals,such as zircon and apatite,can provide powerful tools for provenance analysis.

关键词： apatite detrital apatite U-Pb age trace elements provenance analysis Yarlung River Tibetan Plateau geochronology

Orange-red emitting Sr_3LaTa_3O_(12):Sm^(3+) phosphors with perovskite structure and high thermal stability for w-LEDs

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Journal of Rare Earths 2024年第3期42卷 464-472,I0002页

作者： Xiaopeng Hu Anlin Zhang yufeng du Li Zhou Changlin Li Jingjing Lian Zhequan Zou Xuan Ouyang Bin Deng Lianwu Xie Ruijin Yu College of Chemistry Biology and Environmental Engineering Xiangnan UniversityChenzhou423043China College of Sciences Central South University of Forestry and TechnologyChangsha410004China College of Chemistry&Pharmacy Northwest A&F UniversityYangling712100China Hunan Provincial Key Laboratory of Xiangnan Rare-Precious Metals Compounds Research and Application Xiangnan UniversityChenzhou423043China

A novel layered perovskite tantalate phosphor Sr_(3)LaTa_(3)O_(12):Sm^(3+)(SLTO:Sm^(3+)) with orange-red emission was obtained for the first time via the solid-phase synthetic method. The phase purity, surface morphology,element distribution and luminescent properties of the SLTO:xSm^(3+)(x= 0.01 mol%-0.30 mol%) phosphors were investigated. Under 408 nm excitation, the optimum doped SLTO:0.10Sm^(3+) phosphor emits orangered light at 598 nm with the highest emission peak(4G_(5/2)→6H_(7/2)). The critical energy transfer distance is 1.687 nm. The prepared SLTO:0.10Sm^(3+)phosphor has excellent thermal stability with temperature quenching temperature(T_(0.5)> 500 K) and high activation energy(E_(a)= 0.25 e V). Through calculation, the chromaticity coordinates of all samples are concentrated in the orange-red area, and the color purity reaches 99%. The fabricated white light-emitting diode(w-LED) has a good correlated color temperature(5132 K), a high R_(a)(89), and the CIE chromaticity coordinates(0.340, 0.327). Consequently, the superiority of orange-red-emitting tantalate SLTO:Sm^(3+) phosphors for w-LEDs is demonstrated.

关键词： Tantalate Sr_(3)LaTa_(3)O_(12) Sm^(3+) Luminescence LED Rare earths

地铁出入口原位扩建施工力学行为及关键技术研究

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铁道勘察 2024年第3期50卷 162-170页

作者：杜玉峰北京市轨道交通设计研究院有限公司北京100068 北京市轨道交通工程技术研究中心北京100068

结合北京市轨道交通昌平线南延西土城站改造工程,以既有A出入口改造为研究背景,结合周边环境及地质情况进行方案比选,并对加固措施、破口改造节点、施工步序等关键技术进行优化研究。在此基础上,建立运营地铁出入口洞桩法原位扩建施工... 详细信息

结合北京市轨道交通昌平线南延西土城站改造工程,以既有A出入口改造为研究背景,结合周边环境及地质情况进行方案比选,并对加固措施、破口改造节点、施工步序等关键技术进行优化研究。在此基础上,建立运营地铁出入口洞桩法原位扩建施工全过程三维有限元数值模型,并结合现场监测结果,探究扩建施工诱发的地表沉降与既有出入口结构变形的规律。结果表明:(1)洞桩法施工形成的桩梁拱承载体系可以保护主体结构施工作业的安全,承受地层荷载,有效减小地层沉降和环境影响,保证既有出入口结构的安全;(2)数值模拟结果与现场实测数据基本一致,其中,现场监测与数值模拟结果中,地表最大沉降分别为62.8 mm和65.07 mm,初支扣拱与二衬扣拱两阶段对地表沉降的贡献最大;(3)既有结构主要影响阶段为大开挖阶段,最大沉降为1.4 mm。研究成果可为运营出入口改扩建工程提供新的思路和方法。

关键词：地铁原位扩建洞桩法换乘改造横通道数值模拟

细菌溶解产物对衰老相关肺纤维化小鼠免疫功能的影响

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中华老年医学杂志 2024年第2期43卷 209-215页

作者：钱力孙梓越郭香蕊李丹刘学军韩永康杜毓锋山西医科大学第一医院老年病科太原030001 山西医科大学第一临床医学院太原030001

目的探讨衰老相关肺纤维化与免疫功能的关系及细菌溶解产物对老年小鼠肺纤维化的影响。方法24只老年健康雄性C57BL/6小鼠随机分为对照组(N组)、肺纤维化组(M组)、肺纤维化+细菌溶解产物干预组(P组),M、P组于气管内注射博来霉素(5 mg/kg... 详细信息

目的探讨衰老相关肺纤维化与免疫功能的关系及细菌溶解产物对老年小鼠肺纤维化的影响。方法24只老年健康雄性C57BL/6小鼠随机分为对照组(N组)、肺纤维化组(M组)、肺纤维化+细菌溶解产物干预组(P组),M、P组于气管内注射博来霉素(5 mg/kg)建立小鼠肺纤维化模型,N组注射生理盐水,P组建模后经口注入细菌溶解产物0.4 ml,1次/d,造模28 d后取肺组织和血液。通过苏木精-伊红(HE)和马松三色(Masson)染色检测小鼠肺组织病理变化并进行Ashcroft评分,免疫组化检测肺组织CD4+、CD8+表达,酶联免疫吸附测定(ELISA)法检测小鼠血清干扰素-γ(INF-γ)、白细胞介素-13(IL-13)和免疫球蛋白A(IgA)蛋白含量,实时定量反转聚合酶链式反应(RT-qPCR)检测肺组织INF-γ、IL-13 mRNA的含量,蛋白质免疫印迹法(Western Blot)检测肺组织基质金属蛋白酶-9(MMP-9)和组织型金属蛋白酶抑制剂-1(TIMP-1)蛋白表达水平。结果P组小鼠在细菌溶解产物干预下肺纤维化程度较M组明显减轻;与N组比较,M组CD4+T细胞表达明显减少,CD8+T细胞表达明显增加(P<0.05),IgA含量减少(P<0.05);与M组比较,P组CD4+T细胞表达明显增加,CD8+T细胞表达明显减少(P<0.05),IgA含量升高(P<0.05);细菌溶解产物干预后,IFN-γ的mRNA和蛋白表达水平升高(P<0.05),而IL-13的mRNA和蛋白表达水平降低(P<0.05);与N组相比,M组MMP-9和TIMP-1的蛋白表达显著上调(P<0.05),细菌溶解产物干预后MMP-9和TIMP-1蛋白表达降低(P<0.05)。结论免疫机制参与了肺纤维化的形成,细菌溶解产物可以通过调节机体的免疫平衡状态,从而在一定程度上减轻博来霉素诱导的老年小鼠肺纤维化。

关键词：肺纤维化免疫细菌溶解产物

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叠摞地铁区间轨排井设计方案研究

都市快轨交通 2024年第4期37卷 102-110页

作者：李月阳杜玉峰刘飞王伟锋李哲靳天睿北京市轨道交通设计研究院有限公司北京100068 北京市轨道交通工程技术研究中心北京100068 北京建筑大学土木与交通工程学院北京102612

为选择地铁轨排井合理设计方案,解决设计过程中较大轨排洞口严重削弱板的刚度、施工工况下传统二维框架断面计算无法满足设计需求与实际情况的问题,基于北京地铁22号线管庄站—永顺站区间高水压细颗粒地层中叠摞地铁区间轨排井设计的具... 详细信息

为选择地铁轨排井合理设计方案,解决设计过程中较大轨排洞口严重削弱板的刚度、施工工况下传统二维框架断面计算无法满足设计需求与实际情况的问题,基于北京地铁22号线管庄站—永顺站区间高水压细颗粒地层中叠摞地铁区间轨排井设计的具体案例,从工程围护、主体结构方案的设计思路等方面,分析结构计算重难点等关键问题,并建立二维、三维模型进行结构受力分析。总结设计经验与控制工况,得出合理的设计方案:针对富水地层较深叠摞轨排井,支护结构采用地连墙与内支撑,主体结构采用加大边梁结构体系抵抗水平荷载。研究成果对以后地铁建设过程中的轨排井设计可提供参考。

关键词：城市轨道交通高水压细颗粒地层叠摞地铁区间轨排井设计结构方案

Flammulina velutipes polysaccharide-iron (Ⅲ) complex used to treat iron deficiency anemia after being absorbed via GLUT2 and SGLT1 transporters

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Food Science and Human Wellness 2023年第5期12卷 1828-1840页

作者： Chenying Shi Chen Cheng Xiaotong Lin Yanfang Qian yufeng du Guitang Chen Department of Food Nutrition and Safety/National R&D Center for Chinese Herbal Medicine Processing China Pharmaceutical UniversityNanjing 211198China College of Pharmacy China Pharmaceutical UniversityNanjing 211198China

Iron deficiency anemia(IDA)is a common nutritional problem, but traditional iron supplements cause many adverse reactions. Thus, the development of a novel iron supplement might be significant for the treatment of IDA. This study aimed to study the transport mechanism of Flammulina velutipes polysaccharide-iron complex(FVP1-Fe(Ⅲ))in Caco-2 cells and the therapeutic effect on IDA rats, as well as the influence on gut microbiota in vivo. These results showed that in vitro, the uptake of FVP1-Fe(Ⅲ)was mediated by sodium-dependent glucose transporter-1(SGLT1)and facilitated glucose transporter-2(GLUT2)and GLUT2 played a dominant function. The multidrug resistance-associated protein-2(MRP-2)was involved in the efflux of FVP1-Fe(Ⅲ)across the Caco-2 cells. In vivo, FVP1-Fe(Ⅲ)had a better restorative effect on blood parameters and iron status indicators in rats with IDA as compared with FeSO_4 and exerted this effect by downregulating the expression of hepcidin. FVP1-Fe(Ⅲ)could also regulate gut microbiota dysbiosis in iron deficiency rats by returning the relative abundance of gut microbiota to the normal level. Besides, as a dietary factor, vitamin C(vit C)could enhance the therapeutic effect of FVP1-Fe(Ⅲ). These present findings showed that FVP1-Fe(Ⅲ)could be exploited as a novel iron supplement to treat IDA.

关键词： Flammulina velutipes polysaccharide Iron deficiency anemia Iron supplement Caco-2 cell model Gut microbiota

析出相及夹杂物对L80-9Cr钢耐蚀性的影响

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腐蚀与防护 2024年第6期45卷 21-28页

作者：卢道胜陈宇凡魏安超董社霞刘勇杜宇峰孙冲中海油田服务股份有限公司天津分公司天津300451 中国石油大学(华东)材料科学与工程学院青岛266580 中海油田服务股份有限公司海南分公司海口570312

通过电化学测试和FeCl_(3)点蚀试验,研究了Cr_(23)C_(6)析出相及Al_(2)O_(3)夹杂物对L80-9Cr钢耐蚀性的影响。结果表明:Cr_(23)C_(6)在原马氏体板条束内的析出聚集增大了小角度晶界处的晶格畸变程度,使其具有较高的电化学活性,导致材料... 详细信息

通过电化学测试和FeCl_(3)点蚀试验,研究了Cr_(23)C_(6)析出相及Al_(2)O_(3)夹杂物对L80-9Cr钢耐蚀性的影响。结果表明:Cr_(23)C_(6)在原马氏体板条束内的析出聚集增大了小角度晶界处的晶格畸变程度,使其具有较高的电化学活性,导致材料耐腐蚀性能降低;另一方面,Cr_(23)C_(6)析出导致周围贫Cr区的形成,增大材料的点蚀倾向;此外,Al_(2)O_(3)夹杂物的存在也为点蚀萌生与发展提供有利位置,两者的共同作用导致L80-9Cr钢的严重点蚀。

关键词： L80-9Cr钢 Al_(2)O_(3)夹杂富Cr碳化物 FeCl_(3)点蚀晶格畸变

Colonization and development of the gut microbiome in calves

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Journal of Animal Science and Biotechnology 2023年第4期14卷 1329-1343页

作者： yufeng du Ya Gao Mingyang Hu Jinxiu Hou Linhai Yang Xianghuang Wang Wenjuan du Jianxin Liu Qingbiao Xu College of Animal Sciences and Technology Huazhong Agricultural UniversityWuhan 430070China MoE Key Laboratory of Molecular Animal Nutrition College of Animal SciencesZhejiang UniversityHangzhou 310058China

Colonization and development of the gut microbiome are crucial for the growth and health of *** this review,we summarized the colonization,beneficial nutrition,immune function of gut microbiota,function of the gut barrier,and the evolution of core microbiota in the gut of calves of different *** of gut microbiome is beneficial for nutritional and immune system development of *** of the gut microbiome leads to digestive diseases in calves,such as diarrhea and intestinal *** already exists in the gut of calf fetuses,and the colonization of microbiota continues to change dynamically under the influence of various factors,which include probiotics,diet,age,and *** depends on the interaction between the gut microbiota and the immune system of *** abundance and diversity of these commensal microbiota stabilize and play a critical role in the health of calves.

关键词： Calf Colonization Development Gut health Gut microbiome

3.5%NaCl环境中S32205双相不锈钢与N09925镍基合金的钝化膜特征及耐蚀性

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腐蚀与防护 2024年第6期45卷 15-20页

作者：卢道胜刘慧枫孙永涛董社霞杜宇峰林学强中海油田服务股份有限公司天津分公司天津300451 中国石油大学(华东)材料科学与工程学院青岛266580

采用莫特肖特基(Mott-Schottky)分析方法、电化学阻抗谱(EIS)和X射线光电子能谱(XPS)等,对比研究了S32205双相不锈钢和N09925镍基合金在3.5%NaCl溶液中的钝化膜特征和耐蚀性。结果表明:N09925镍基合金表面钝化膜的缺陷密度低于S32205双... 详细信息

采用莫特肖特基(Mott-Schottky)分析方法、电化学阻抗谱(EIS)和X射线光电子能谱(XPS)等,对比研究了S32205双相不锈钢和N09925镍基合金在3.5%NaCl溶液中的钝化膜特征和耐蚀性。结果表明:N09925镍基合金表面钝化膜的缺陷密度低于S32205双相不锈钢,两种材料表面的钝化膜中均存在Fe和Cr元素富集,主要成分为Cr和Fe的氧化物和氢氧化物;S32205双相不锈钢表面钝化膜中含有少量金属Ni,N09925镍基合金表面钝化膜中Ni含量较高,还含有Ni的氧化物和氢氧化物;N09925镍基合金的阻抗值更高,其膜层电阻和电荷传递电阻均高于S32205双相不锈钢,N09925镍基合金表面钝化膜的保护性高于S32205双相不锈钢。

关键词： S32205双相不锈钢 N09925镍基合金钝化膜电化学测试 X射线光电子能谱(XPS)