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Three-stage niobium mineralization at Bayan Obo, China

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National Science Review 2024年第4期11卷 102-110页

作者： Yan Yu yang li Yu liu xiao-xiao ling li-Guang Wu li yang Lan yang Bo yang Yong-Gang Zhao Xian-Hua li State Key Laboratory of lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(REE) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo

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市政园林绿化工程施工技术及质量控制

建筑与装饰 2024年第8期 133-135页

作者：鲍德方杨晓丽管斐青岛市黄岛区建筑工务中心山东青岛 266555 青岛海洋投资集团有限公司山东青岛 266555

市政园林绿化工程不仅能改善城市面貌,还能创造较大的经济、社会与生态效益.但由于市政园林绿化工程的艺术性、生态性与功能性,在施工建设期间不仅需加强技术管理,还需注重质量控制,以确保市政园林绿化工程的景观效果.当前我国的园林绿... 详细信息

市政园林绿化工程不仅能改善城市面貌,还能创造较大的经济、社会与生态效益.但由于市政园林绿化工程的艺术性、生态性与功能性,在施工建设期间不仅需加强技术管理,还需注重质量控制,以确保市政园林绿化工程的景观效果.当前我国的园林绿化工程施工技术越发先进,未来需继续加大技术创新力度.基于此,本文从市政园林绿化工程的特点着手,重点分析了此类工程中的技术要点及质量控制措施,以期为同类型项目提供指导与借鉴.

关键词：市政园林绿化工程施工技术质量控制

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信息化技术在建筑工程经济管理中的应用

Percutaneous drainage in the treatment of intrahepatic pancreatic pseudocyst with Budd-Chiari syndrome:A case report

科学与信息化 2024年第6期 41-43页

作者：杨晓丽管斐鲍德方青岛市黄岛区建筑工务中心山东青岛 266555 青岛海洋投资集团有限公司山东青岛 266555

技术进步的今天,传统的建筑工程经济管理方式暴露了诸多问题,难以提高管理效能.为符合行业现代化发展趋势,建筑工程经济管理应寻求技术的变革,以凸显管理作用.为便于整合与利用数据,建筑工程经济管理中应推广信息化技术,构建现代化管理... 详细信息

技术进步的今天,传统的建筑工程经济管理方式暴露了诸多问题,难以提高管理效能.为符合行业现代化发展趋势,建筑工程经济管理应寻求技术的变革,以凸显管理作用.为便于整合与利用数据,建筑工程经济管理中应推广信息化技术,构建现代化管理体系.当下许多建筑项目在经济管理中成功应用了信息技术,未来这些企业还需继续创新信息技术的形式.基于此,本文重点分析了建筑工程经济管理中信息化技术的应用,以期指导实际工作.

关键词：建筑工程经济管理信息化技术应用

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World Journal of Clinical Cases 2021年第28期9卷 8476-8481页

作者： Gang Zhu Yi-Sheng Peng Cheng Fang xiao-li yang Bo li Department of General Surgery(Hepatobiliary Surgery) Academician(Expert)Workstation of Sichuan ProvinceThe Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina

BACKGROUND Intrahepatic pancreatic pseudocyst(IHPP)is an extremely rare complication of acute pancreatitis,with only a few cases previously described in the *** the best of our knowledge,IHPP with Budd-Chiari syndrome(BCS)has not yet been *** SUMMARY A 35-year-old male presented with abdominal pain,vomiting and anorexia,followed by severe swelling of the lower body after 4 *** morphological assessment(using computed tomography revealed the presence of a huge cyst of 18.28 cm×10.34 cm under the liver capsule accompanied by a large amount of *** puncture allowed us to detect a high level of amylase in the collection,confirming the diagnosis of *** cyst was treated by percu-taneous drainage,producing complete resolution of the *** IHPP can be treated with percutaneous drainage,endoscopic drainage,surgery or even conservative treatment,depending on the specific *** recommend percutaneous drainage as the first choice of treatment when IHPP with secondary BCS.

关键词： Intrahepatic pancreatic pseudocyst Pancreatic pseudocyst Pancreatitis Budd�Chiari syndrome Percutaneous drainage Case report

黄河中游河口-龙门区间蓝绿水资源对气候与土地利用变化的响应

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中国农村水利水电 2024年第3期 24-33页

作者：黄怡婷杨肖丽吴凡王宇航张晗硕河海大学水文水资源学院江苏南京210098 河海大学水灾害防御全国重点实验室江苏南京210098

气候变化和土地利用变化会改变蓝绿水资源的时空分布,量化二者变化所带来的影响对水资源管理具有重要意义。黄河中游的河龙区间(河口镇至龙门)社会经济的迅速发展和大规模生态修复工程的实施改变了流域的土地利用格局,蓝绿水资源时空分... 详细信息

气候变化和土地利用变化会改变蓝绿水资源的时空分布,量化二者变化所带来的影响对水资源管理具有重要意义。黄河中游的河龙区间(河口镇至龙门)社会经济的迅速发展和大规模生态修复工程的实施改变了流域的土地利用格局,蓝绿水资源时空分布受到影响。研究基于遥感数据,分析河龙区间近40年土地利用的变化特征;结合VIC模型和四种情景设置,定量分析气候与土地利用变化对流域内蓝绿水的时空影响。进一步分析了生产性绿水流及非生产性绿水流对气候及土地利用变化的响应规律,以便开发绿水资源的生产潜力。结果表明:(1)河龙区间平均最高气温和平均最低气温在1997年发生突变,变化趋势由减小转为增大;降水量在2006年发生突变,变化趋势由减少转为增加。草地和耕地是河龙区间的主要土地利用类型,1980-2020年间耕地减少了3 407 km^(2),林地、草地和灌木林的面积均呈现增加趋势,与退耕还林还草工程的实施密切相关。(2)气候变化和土地利用变化对蓝水流的贡献率分别为90.89%和9.11%,对绿水流的贡献率分别为103.13%、-3.13%,对绿水储的贡献率分别为89.07%、10.93%,气候变化对河龙区间蓝绿水变化起主导作用。4种情景下,河龙区间的蓝水流、绿水流、绿水储均呈现从西北到东南逐渐增加的趋势。(3)植被恢复下,植被蒸腾作为生产性绿水流占总绿水流的比例由71.63%增大到72.93%。4种情景下,植被冠层截留蒸发量、植被蒸腾量的空间分布呈现从西北到东南地区增加的趋势,而裸土蒸发量呈现相反的空间分布格局。气候变化下,植被冠层截留蒸发量、植被蒸腾量呈增加趋势,土地利用变化对裸土蒸发量的影响更大。

关键词：气候变化土地利用变化蓝绿水 VIC模型河龙区间

Navigation Finsler metrics on a gradient Ricci soliton

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 266-275页

作者： li Ying MO xiao-huan WANG xiao-yang Department of Applied Mathematics Zhejiang University of TechnologyHangzhou 310023China Key Laboratory of Pure and Applied Mathematics School of Mathematical SciencesPeking UniversityBeijing 100871China School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081China

In this paper,we study a class of Finsler metrics defined by a vector field on a gradient Ricci *** obtain a necessary and sufficient condition for these Finsler metrics on a compact gradient Ricci soliton to be of isotropic S-curvature by establishing a new integral *** we determine the Ricci curvature of navigation Finsler metrics of isotropic S-curvature on a gradient Ricci soliton generalizing result only known in the case when such soliton is of Einstein *** its application,we obtain the Ricci curvature of all navigation Finsler metrics of isotropic S-curvature on Gaussian shrinking soliton.

关键词： gradient Ricci soliton navigation Finsler metric isotropic S-curvature Ricci curvature Gaussian shrinking soliton

Trace formula of the integro-differential operator on a quantum graph

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 311-318页

作者： WEI li-xiao yang Chuan-fu School of Mathematics and Statistics Nanjing University of Science and TechnologyNanjing 210094China.

In this paper we study the eigenvalue problem for integro-differential operators on a lasso *** trace formula of the operator is established by applying the residual technique in complex analysis.

关键词： integro-differential operators eigenvalue trace formula

Comparative mitogenomic analyses unveil conserved and variable mitogenomic features and phylogeny of Chedrinae fish

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Zoological Research 2022年第1期43卷 30-32页

作者： Peng Yu li Zhou xiao-li yang liang-liang li Hui Jin Zhi li Zhong-Wei Wang Xi-Yin li xiao-Juan Zhang yang Wang Jian-Fang Gui State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyInnovation Academy of Seed DesignChinese Academy of SciencesWuhanHubei 430072China Hubei Hongshan Laboratory WuhanHubei 430070China University of Chinese Academy of Sciences Beijing 10049China

Chedrinae fish,which belong to Danionidae,have important ornamental,economic,and scientific *** present,however,their mitogenomic features are unclear and their phylogenetic relationships remain *** this study,we presented five new Chedrinae mitochondrial genomes(mitogenomes)and analyzed the conserved and variable mitogenomic characteristics of 17 Chedrinae *** gene composition and arrangement and secondary structure of transfer RNAs(tRNAs)were highly conserved among the Chedrinae ***,the length of the control region and base composition were ***,the mitogenome of Barilius barila was unusual,with lower A+T content in the first codon of protein-coding genes(PCGs)(47.32%versus average of 54.47%)and distinct pattern of codons per thousand codons(CDspT).Three Chedrinae fish had a long tandem repeat(>291 bp)in the 5'-end of the control region,which may increase their *** addition,tRNALys had notably larger DHU and TΨC loops than other *** phylogenetic trees of the Chedrinae fish suggested that the Barilius genus was not a monophyletic group but could be divided into two main groups based on significant differences in A+T *** study provides insights into the mitogenomic features and phylogenetic implications of Chedrinae fish,which should benefit their systematics and conservation.

关键词： conserved fish features

Evaluation of high-resolution satellite precipitation products with surface rain gauge observations from Laohahe Basin in northern China

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Water Science and Engineering 2010年第4期3卷 405-417页

作者： Shan-hu JIANG li-liang REN Bin YONG xiao-li yang lin SHI State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 P. R. China

Three high-resolution satellite precipitation products, the Tropical Rainfall Measuring Mission （TRMM） standard precipitation products 3B42V6 and 3B42RT and the Climate Precipitation Center＇s （CPC） morphing technique precipitation product （CMORPH）, were evaluated against surface rain gauge observations from the Laohahe Basin in northern China. Widely used statistical validation indices and categorical statistics were adopted. The evaluations were performed at multiple time scales, ranging from daily to yearly, for the years from 2003 to 2008. The results show that all three satellite precipitation products perform very well in detecting the occurrence of precipitation events, but there are some different biases in the amount of precipitation. 3B42V6, which has a bias of 21%, fits best with the surface rain gauge observations at both daily and monthly scales, while the biases of 3B42RT and CMORPH, with values of 81% and 67%, respectively, are much higher than a normal receivable threshold. The quality of the satellite precipitation products also shows monthly and yearly variation： 3B42RT has a large positive bias in the cold season from September to April, while CMORPH has a large positive bias in the warm season from May to August, and they all attained their best values in 2006 （with 10%, 50%, and -5% biases for 3B42V6, 3B42RT, and CMORPH, respectively）. Our evaluation shows that, for the Laohahe Basin, 3B42V6 has the best correspondence with the surface observations, and CMORPH performs much better than 3B42RT. The large errors of 3B42RT and CMORPH remind us of the need for new improvements to satellite precipitation retrieval algorithms or feasible bias adjusting methods.

关键词： satellite precipitation product TRMM 3B42RT TRMM 3B42V6 CMORPH surface rain gauge observation Laohahe Basin