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Three-stage niobium mineralization at Bayan Obo, China

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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pH-responsive metal nanoparticles as high contrast theranostic agents for selective imaging and synergistic cancer therapy

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Science China Chemistry 2024年第9期67卷 3063-3070页

作者： Sichao Tian xiaofeng He xiao Wu Dongxue Hu Qing-Hua Xu Department of Chemistry National University of SingaporeSingapore 117543Singapore national University of Singapore(Suzhou)Research Institute Suzhou 215123China Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Department of Biological Sciences Faculty of ScienceNational University of SingaporeSingapore 117558Singapore

The low signal-to-noise ratio(S/n)and single functionality of fluorescence imaging agents have limited their practical *** two-photon excitation(2PE)imaging probes are highly desirable in vivo with larger imaging depth,minor autofluorescence background,and less ***,we developed responsive aggregated gold nanoparticles(Au nPs)as high contrast 2PE imaging agents,capable of emitting red fluorescence upon excitation of near-infrared(nIR)laser and possessing a high signal-to-noise ratio(S/n of 2,475).By forming aggregates in situ inside tumor tissue,doxorubicin hydrochloride(DOX)-loaded mix-charged gold nanoparticles(DOX-MC-Au nPs)were utilized to act as selective fluorescence imaging probes and precise therapy *** high-contrast theranostic agents offer a promising potential for precise cancer imaging and therapy,which might open a new venue to multifunctional and noninvasive theranostics.

关键词： metal nanoparticles two-photon excitation high contrast imaging agents fluorescence imaging cancer therapy

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Influence of topography on the fine structures of stratospheric gravity waves:An analysis using COSMIC-2 temperature data

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Earth and Planetary Physics 2024年第3期8卷 497-513页

作者： JiaRui Wei xiao Liu JiYao Xu QinZeng Li Hong Gao State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Institute of Electromagnetic Wave School of PhysicsHenan Normal UniversityXinxiang Henan 453000China

We derive the potential energy of gravity waves(GWs)in the upper troposphere and stratosphere at 45°S-45°n from December 2019 to november 2022 by using temperature profiles retrieved from the Constellation Observing System for Meteorology,Ionosphere,and Climate-2(COSMIC-2)*** to the dense sampling of COSMIC-2,in addition to the strong peaks of gravity wave potential energy(GWPE)above the Andes and Tibetan Plateau,we found weak peaks above the Rocky,Atlas,Caucasus,and Tianshan *** land-sea contrast is responsible for the longitudinal variations of the GWPE in the lower and upper *** 40°n/S,the peaks were mainly above the topographic regions during the *** 20°n/S,the peaks were a slight distance away from the topographic regions and might be the combined effect of nontopographic GWs and mountain *** the Equator,the peaks were mainly above the regions with the lowest sea level altitude and may have resulted from *** results indicate that even above the local regions with lower sea level altitudes compared with the Andes and Tibetan Plateau,the GWPE also exhibits fine structures in geographic *** found that dissipation layers above the tropopause jet provide the body force to generate secondary waves in the upper stratosphere,especially during the winter months of each hemisphere and at latitudes of greater than 20°n/S.

关键词： topography fine structures stratospheric gravity waves Constellation Observing System for Meteorology Ionosphere and Climate-2(COSMIC-2) dissipation layers

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On the Factors Influencing the High Stretch-Flangeability of a Low-Density 1180 MPa Fe-Mn-Al-C-nbδ-QP Steel

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1291-1300页

作者： Dan‑Dan Cui Peng Chen Peng‑Fei Wang xiao‑Wu Li Department of Materials Physics and Chemistry School of Materials Science and Engineeringand Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

Low-densityδ-quenching and partitioning(δ-QP)steels with excellent strength and ductility have been recently ***,there are still rare reports on the formability of δ-QP steels,which are critical for satisfying the manufacture of structural parts during the application in automotive *** the present work,an 1180 MPa Fe–Mn–Al–C–nbδ-QP steel with a high ductility was adopted for the stretch–flangeability ***δ-QP steel was developed by separated quenching and partitioning processes.A good hole expansion ratio(HER)of 34.9±0.9%was obtained in the quenched steel,but it has been further increased to 52.2%by the tempering *** improved stretch–flangeability was attributed to the enhanced austenite stability and deformation *** the one hand,the stability of austenite was increased by carbon partitioning during tempering,which reduced crack possibility via the suppression of the fresh martensite *** the other hand,the tempering treatment released the internal stress caused by martensitic transformation and reduced the difference in strength among different phases,resulting in an increase in the resistance to crack initiation and propagation.

关键词： Hole expansion ratio Low-densityδ-quenching and partitioning(δ-QP)steel Stretch-flangeability Austenite stability Deformation uniformity

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Eutrophication of Jiangsu Coastal Water and Its Role in the Formation of Green Tide

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Journal of Ocean University of China 2024年第1期23卷 109-118页

作者： xiao Mingyan SOnG Weina ZHAnG Haibo SHI xiaoyong SU Rongguo Key Laboratory of Marine Chemistry Theory and Technology Ministry of EducationOcean University of ChinaQingdao 266100China national Marine Environmental Monitoring Center Dalian 116000China national Marine Hazard Mitigation Service Beijing 100194China

Since 2007,the large-scale green tide caused by Ulva prolifera(***)have occurred as a recurrent phenomenon in the southern Yellow Sea of *** surveys and satellite remote sensing showed that the small scattered patches of green tide algae were first observed along the Porphyra agriculture area of the Subei Shoal in late *** this study,we attempted to identify the role of eutrophication in the origin of the green tide in the Subei Shoal and its adjacent *** Shoal and its adjacent area are characterized by rich nutrients,especially nO_(3)^(-)-n,nH_(4)^(+)-n,PO_(4)^(3-)-P,and other bioavailable components(such as urea-n and amino acids).In the spring of 2017,the average concentrations of nO_(3)^(-)-n were 19.01±11.01μmolL^(-1),accounting for 86.68%of the dis-solved inorganic nitrogen(DIn).In addition,the average concentration of nH4^(+)-n was 2.51±1.60μmolL^(-1).PO_(4)^(3-)-P had an average concentration of 0.14±0.13μ*** average concentrations of urea-n and total hydrolyzed amino acids(THAA)were 1.73±1.36μmolL^(-1)and 1.33±0.80μmolL^(-1),*** nutritive substances play a key role in the rapid production of *** and make the Jiangsu coastal water an incubator for green tide.

关键词： green tide nutrients algae Ulva prolifera eutrophication Subei Shoal

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Recent Developments of Photodeformable Polymers:From Materials to Applications

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Research 2024年第2期2023卷 729-752页

作者： Shuting Kong Hailan Wang Eethamukkala Ubba Yuxin xiao Tao Yu Wei Huang Frontiers Science Center for Flexible Electronics(FSCFE) Shaanxi Institute of Flexible Electronics(SIFE)Northwestern Polytechnical University127 West Youyi RoadXian 710072China OMC Research Laboratory.Department of Chemistry School of Advanced SciencesVITVelloreTamilnaduIndia Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Nanjing Tech University(NanjingTech)30 South Puzhu RoadNanjing 211816China State Key Laboratory of Organic Electronics and Information Displays&Institute of Advanced Materials(IAM) Nanjing University of Posts and Telecommunications9 Wenyuan RoadNanjing 210023China

Photodeformable polymer materials have a far influence in the fields of flexibility and *** stimulation energy is converted into mechanical energy through molecular *** kinds of photodeformable polymer materials,liquid crystalline polymer(LCP)photodeformable materials have been a hot topic in recent *** such as azobenzene,a-cyanostilbene,and 9,10-dithiopheneanthracene have been widely used in LCP,which are helpful for designing functional molecules to increase the penetration depth of light to change physical *** to the various applications of photodeformable polymer materials,there are many excellent reports in intelligent *** this review,we have systematized LCP containing azobenzene into 3 categories depending on the degree of crosslinking liquid crystalline elastomers,liquid crystalline networks,and linear *** structural,typical polymer materials and their applications are *** issues faced and future directions to be developed for photodeformable polymer materials are also summarized.

关键词： properties. field. crystalline

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Understanding the Interfacial Energy Structure and Electron Extraction Process in Inverted Organic Solar Cells with Phosphine-Doped Cathode Interlayers

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Chinese Journal of Chemistry 2024年第12期42卷 1347-1354页

作者： Yi Yang Jingwen Wang Yang xiao Bowei Xu Jianhui Hou State Key Laboratory of Polymer Physics and Chemistry Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China State Key Laboratory of Chemical Resource Engineering College of Materials Science and EngineeringBeijing University of Chemical TechnologyBejing 100029China University of Chinese Academy of Sciences Beijing 100049China

Comprehensive Summary Cathode interlayers(CILs)play an essential role in achieving efficient organic solar cells(OSCs).However,the electronic structure at the electrode/CIL/active layer interfaces and the underlying mechanisms for electron collection remain unclear,which becomes a major obstacle to develop high-performance ***,we investigate the relationship of the electron collection abilities of four cross-linked and n-doped CILs(c-nDI:P0,c-nDI:P1,c-nDI:P2,c-nDI:P3)with their electronic structure of space charge region at heterojunction *** accurately calculating the depletion region width according to the barrier height,doping density and permittivity,we put forward that the optimal thickness of CIL should be consistent with the depletion region width to realize the minimum energy *** a result,the depletion region width is largely reduced from 13 nm to 0.8 nm at the indium tin oxide(ITO)/c-nDI:P0 interface,resulting in a decent PCE of 17.7%for the corresponding inverted OSCs.

关键词： Organic solar cells Cathode interlayer Depletion region width Electric conductivity Electron transport Electron transfer Electron extraction process

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Analysis of the impact of immunotherapy efficacy and safety in patients with gastric cancer and liver metastasis

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 700-709页

作者： Kai Liu Chun-xiao Wu Hui Liang Tao Wang Ji-Yuan Zhang xiao-Tao Wang Department of Radiation and Oncology Traditional Chinese Hospital of Lu’an affiliated to Anhui University of Traditional Chinese MedicineLu’an 237000Anhui ProvinceChina Department of Gastroenterology Ehu branch of Xishan People’s Hospital of Wuxi CityWuxi 214116Jiangsu ProvinceChina Department of Gastrointestinal Surgery The First Affiliated Hospital of Guangzhou University of Traditional Chinese MedicineGuangzhou 510400Guangdong ProvinceChina Department of Gastrointestinal Surgery Hunan Provincial People’s HospitalChangsha 410002Hunan ProvinceChina Department of Traditional Chinese medicine Ehu branch of Xishan People’s Hospital of Wuxi CityWuxi 214116Jiangsu ProvinceChina

BACKGROUnD Gastric cancer(GC)is the fifth most common type of cancer and has the fourth highest death rate among all *** is a lack of studies examining the impact of liver metastases on the effectiveness of immunotherapy in individuals diagnosed with *** To investigate the influence of liver metastases on the effectiveness and safety of immunotherapy in patients with advanced *** This retrospective investigation collected clinical data of patients with advanced stomach cancer who had immunotherapy at our hospital from February 2021 to January *** baseline attributes were compared using either the Chi-square test or the Fisher exact probability *** chi-square test and Kaplan-Meier survival analysis were employed to assess the therapeutic efficacy and survival duration in GC patients with and without liver *** The analysis comprised 48 patients diagnosed with advanced GC,who were categorized into two groups:A liver metastasis cohort(n=20)and a non-liver metastatic cohort(n=28).Patients with liver metastasis exhibited a more deteriorated physical condition compared to those without liver *** objective response rates in the cohort with metastasis and the cohort without metastasis were 15.0%and 35.7%(P>0.05),***,the disease control rates in these two cohorts were 65.0%and 82.1%(P>0.05),*** median progression-free survival was 5.0 months in one group and 11.2 months in the other group,with a hazard ratio of 0.40 and a significance level(P)less than *** median overall survival was 12.0 months in one group and 19.0 months in the other group,with a significance level(P)greater than *** Immunotherapy is less effective in GC patients with liver metastases compared to those without liver metastasis.

关键词： Gastric cancer Spread of cancer to the liver Treatment with immunotherapy Effectiveness of treatment

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Shear-thinning Catechol-modified Chitosan Hydrogel Loaded with Silver nanoparticles for Endoscopic Submucosal Dissection

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Chinese Journal of Polymer Science 2024年第8期42卷 1147-1155页

作者： Wen-Jun Feng Yan-He Wu xiao-Yang Liu Zheng-Ke Wang MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310058China

Shear-thinning hydrogels have emerged for endoscopic submucosal dissection,while wound intervention after surgery has rarely been ***,a catechol-modified chitosa n hydrogel with shear-thinning property was developed for simultaneously facilitating endoscopic submucosal dissection and postoperative wound *** from the shear-thinning and self-healing characteristics,the asprepared hydrogel showed easily endoscopic *** also performed very well as submucosal cushion,which could remain above 70%after injection for 120 min in ex vivo porcine large intestine *** fact,the cushion height of normal saline dramatically decreased to 46%of the initial height at 30 *** nanoparticles encapsulated into the network endowed the hydrogel with almost reached 100%antibacterial effect against *** and *** hemolysis ratio of the hydrogel was calculated to be as low as 0.8%.Combined with good hemocompatibility and cytocompatibility,the as-prepared hydrogel displayed much higher in vivo wound closu re and healing efficacy than normal *** results demonstrated the superiority of the shear-thinning chitosan hydrogel in facilitating clinical endoscopic submucosal dissection surgery.

关键词： Shear-thinning hydrogel Endoscopic mucosal dissection Wound healing Catechol-modified chitosan Silver nanoparticles

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Self-doping active sites in microbe-derived carbonaceous electrocatalysts for the oxygen reduction reaction performance

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nano Research 2024年第8期17卷 6803-6819页

作者： xiaofeng xiao xiaochun Tian Junpeng Li Fan Yang Rui Bai Feng Zhao Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Microorganisms are rich in heteroatoms,which can be self-doped to form active sites during pyrolysis and loaded on microbederived carbonaceous *** recent years,microbe-derived carbonaceous materials,characterized with abundant selfdoping sites,have been continuously developed as cost-effective electrocatalysts for oxygen reduction reaction(ORR).To fully unlock the catalytic potential of microbe-derived carbonaceous materials,a comprehensive analysis of catalytic sites and mechanisms for ORR is *** paper provides a summary of the ORR catalytic performance of microbe-derived carbonaceous materials reported to date,with a specific focus on the self-doping sites introduced during their pyrolytic *** highlights the mono-or co-doping sites involving nonmetallic elements such as oxygen(O),nitrogen(n),phosphorus(P),and sulfur(S)atoms,as well as covers the doping of metallic iron(Fe)atoms with various coordination configurations in microbe-derived carbonaceous *** the impact of these self-doping sites on ORR catalytic performance can guide the design of doping sites in microbe-derived carbonaceous *** approach has the potential to maximize electrocatalytic activity of microbe-derived carbonaceous materials and contributes to the development of more efficient and cost-effective carbonaceous electrocatalysts.

关键词： electrocatalysis heteroatoms self-doped single atom catalyst microbe-derived carbonaceous material

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