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Nd^(3)+:YAG-Al_(2)O_(3) nanocrystalline transparent ceramics with high inflexion concentration quenching of Nd^(3+) prepared by amorphous crystallization

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Journal of Advanced Ceramics 2024年第8期13卷 1242-1253页

作者： Xiujuan Wan Guangfan Tan Liang Cai jie fu Jianqiang Li Yingchun Zhang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100080China State Key Lab for Mesoscience and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

Rare earth ion-doped Y_(3)Al_(5)O_(12)(YAG)-based transparent ceramics have been used as important laser gain media for a long time,yet the doping concentration of active ions is limited due to concentration quenching,wherein the inflexion concentration quenching of Nd^(3+)is recognized as 1.0 at%.In this work,YAG-Al_(2)O_(3) nanocrystalline transparent ceramics with a concentration of Nd^(3+)(O-5.0 at%)were fabricated via amorphous crystallization,and the crystal structure evolution,morphology,and optical properties were systematically investigated by differential scanning calorimetry(DSC),X-ray powder diffraction(XRD),transmission electron microscopy(TEM),magnetic resonation(MAS),nuclear magnetic resonation(NMR),and fluorescence *** doping of Nd^(3+)can promote the transition of Al[5]and Al[6]to Al[14],indicating improvements in the ability of the amorphous material to form Nd^(3+):Y_(2)O_(3)-Al_(2)O_(3) vitrified beads,and 1.5 at%Nd^(3+):YAG-Al_(2)O_(3) nanocrystalline transparent ceramics can be obtained by crystallization at 1050℃ with a matrix composed of YAG and concomitant δ-Al_(2)O_(3) and θ-Al_(2)O_(3).The nanocrystalline transparent ceramics show an internal transmitance of 89.56%at 1064 nm,and the strongest emission peak corresponds to the energy transfer from 4F_(3/2) to 4l_(11/2) of Nd^(3+)with a fluorescence lifetime of 231μs when pumped by an 808 nm ***,spectral broadening begins to occur,indicating the onset of concentration quenching,when the concentration of Nd^(3+)exceeds 1.5 at%,substantially higher than the 1.0 at% observed in YAG ***-Al_(2)O_(3) nanocrystalline transparent ceramics obtained by amorphous crystalization can be utilized as the matrix to increase the inflexion point of doping concentration quenching of Nd^(3+),and this material may have great potential as a laser gain medium.

关键词： Y_(3)Al_(5)O_(12)(YAG)-Al_(2)O_(3) nanocrystalline transparent ceramics laser gain medium Nd^(3+)

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Quantitative prediction model for the depth limit of oil accumulation in the deep carbonate rocks:A case study of Lower Ordovician in Tazhong area of Tarim Basin

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Petroleum Science 2024年第1期21卷 115-124页

作者： Wen-Yang Wang Xiong-Qi Pang Ya-Ping Wang Zhang-Xin Chen fu-jie Jiang Ying Chen State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Research Institute of Exploration and Development PetroChina Southwest Oil&Gas Field CompanyChengdu610041SichuanChina Chemical and Petroleum Engineering Schulich School of EngineeringUniversity of CalgaryCalgaryT2N 1N4Canada

With continuous hydrocarbon exploration extending to deeper basins,the deepest industrial oil accumulation was discovered below 8,200 m,revealing a new exploration ***,the extent to which oil exploration can be extended,and the prediction of the depth limit of oil accumulation(DLOA),are issues that have attracted significant attention in petroleum *** it is difficult to characterize the evolution of the physical properties of the marine carbonate reservoir with burial depth,and the deepest drilling still cannot reach the ***,the DLOA cannot be predicted by directly establishing the relationship between the ratio of drilling to the dry layer and the *** this study,by establishing the relationships between the porosity and the depth and dry layer ratio of the carbonate reservoir,the relationships between the depth and dry layer ratio were obtained *** depth corresponding to a dry layer ratio of 100%is the *** on this,a quantitative prediction model for the DLOA was finally *** results indicate that the porosity of the carbonate reservoir,Lower Ordovician in Tazhong area of Tarim Basin,tends to decrease with burial depth,and manifests as an overall low porosity reservoir in deep *** critical porosity of the DLOA was 1.8%,which is the critical geological condition corresponding to a 100%dry layer ratio encountered in the *** depth of the DLOA was 9,000 *** study provides a new method for DLOA prediction that is beneficial for a deeper understanding of oil accumulation,and is of great importance for scientific guidance on deep oil drilling.

关键词： Deep layer Tarim Basin Hydrocarbon accumulation Depth limit of oil accumulation Prediction model

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3D printed silicon-based micro-lattices with ultrahigh areal/gravimetric capacities and robust structural stability for lithium-ion batteries

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Nano Research 2024年第4期17卷 2693-2703页

作者： jie fu Dong Wang Yan Li Xianzheng Liu Rui Zhang Zhiyuan Liu Pengdong Liu Lijuan Zhang Xuefei Li Guangwu Wen School of Materials Science and Engineering Shandong University of TechnologyZibo 255000China Shandong Si-Nano Materials Technology Co. Ltd.Zibo 255000China

Nanostructured silicon anodes have shown extraordinary lithium storage properties for lithium-ion batteries(LIBs)but are usually achieved at low areal loadings(<1.5 mg·cm^(-2))with low areal *** sound electrochemical... 详细信息

Nanostructured silicon anodes have shown extraordinary lithium storage properties for lithium-ion batteries(LIBs)but are usually achieved at low areal loadings(fusion,and the carbonaceous network provides excellent electron transport properties and mechanical integrity,thus endowing the printed 3D-Si/G/C electrode with fast electrochemical reaction kinetics and reversibility at high mass ***,the 3D-Si/G/C with high areal mass loading of 12.9 mg·cm^(-2) exhibits excellent areal capacity of 12.8 mAh·cm^(-2) and specific capacity of 1007 mAh·g^(-1),***-situ optical microscope and ex-situ scanning electron microscope(SEM)confirm that the hierarchically porous filaments with interconnected carbon skeletons effectively suppress the volume change of silicon and maintain stable micro-lattice architecture.A 3D printed 3D-Si/G/C-1||3D-LiFePO_(4)/G full cell holds excellent cyclic stability(capacity retention rate of 78%after 50 cycles)with an initial Coulombic efficiency(ICE)of 96%.This work validates the feasibility of 3D printing on constructing high mass loading silicon anode for practical high energy-density LIBs.

关键词： silicon anode areal capacity three-dimensional(3D)printing lithium-ion batteries

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Fate of organophosphate esters from the Northwestern Pacific to the Southern Ocean:Occurrence,distribution,and fugacity model simulation

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Journal of Environmental Sciences 2024年第3期137卷 347-357页

作者： Tengda Shi Ruijing Li jie fu Chao Hou Hui Gao Guanjie Cheng Haibo Zhang Shuaichen Jin Liang Kong Guangshui Na College of Marine Technology and Environment Dalian Ocean UniversityDalian 116023China Laboratory for coastal marine eco-environment process and carbon sink of Hainan province/Yazhou Bay Innovation Institute Hainan Tropical Ocean UniversitySanya 572022China National Marine Environmental Monitoring Center Dalian 116023China College of Marine Ecology and Environment Shanghai Ocean UniversityShanghai 201306China NCS Testing Technology Co. Ltd.Beijing 10081China

Eleven organophosphate esters(OPEs)in the air and seawater were investigated from the northwestern Pacific Ocean to the Southern Ocean during the 2018 Chinese 34th Antarctic Scientific *** concentration of total OPEs ranged from 164.82 to 3501.79 pg/m~3in air and from 4.54 to 70.09 ng/L in *** halogenated OPEs,tri(chloropropyl)phosphate(TCPP)and tri(2-chloroethyl)phosphate(TCEP),were generally more abundant than the non-halogenated OPEs.A levelⅢfugacity model was developed to simulate the transfer and fate of seven OPEs in the air and seawater regions of the central Ross *** model results indicate that OPEs are transferred from the air to the seawater in the central Ross Sea in summer,during which the Ross Sea acts as a final OPE *** and wet deposition dominated the processes involving OPE transfer to *** OPE degradation process was also found to be more pervasive in the atmosphere than in the seawater *** findings highlights the importance of long-range transport of OPEs and their air–seawater interface behavior in the Antarctic.

关键词： Organophosphate esters(OPEs) Long-range transport fugacity model Antarctic Fate

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Quantitative effect of kerogen type on the hydrocarbon generation potential of Paleogene lacustrine source rocks,Liaohe Western Depression,China

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Petroleum Science 2024年第1期21卷 14-30页

作者： Sha-Sha Hui Xiong-Qi Pang fu-jie Jiang Chen-Xi Wang Shu-Xing Mei Tao Hu Hong Pang Min Li Xiao-Long Zhou Kan-Yuan Shi State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Exploration and Development Research Institute PetroChina Liaohe Oilfield CompanyPanjin 124010LiaoningChina

Kerogen types exert a decisive effect on the onset and capacity of hydrocarbon generation of source *** source rocks in the Liaohe Western Depression are characterized by thick deposition,high total organic carbon(TOC)content,various kerogen types,and a wide range of thermal ***,their hydrocarbon generation potential and resource estimation can be *** this study,geochemical tests,numerical analysis,hydrocarbon generation kinetics,and basin modeling were integrated to investigate the differential effects of kerogen types on the hydrocarbon generation potential of lacustrine source *** hydrocarbon generation and expulsion(HGE)models of different kerogen types were established quantitatively upon abundant Rock-Eval/TOC/vitrinite reflectance(R_(o))*** sets of good-excellent source rocks deposited in the fourth(Es4),third(Es3),and first(Es1)members of Paleogene Shahejie Formation,are predominantly types I-II_(1),II_(1)-II_(2),and II-III,*** activation energy of types I-II_(2)kerogen is concentrated(180-230 kcal/mol),whereas that of type III kerogen is widely distributed(150-280 kcal/mol).The original hydrocarbon generation potentials of types I,II_(1),II_(2),and III kerogens are 790,510,270,and 85 mg/g TOC,*** Ro values of the hydrocarbon generation threshold for type I-III source rocks gradually increase from 0.42%to 0.74%,and Ro values of the hydrocarbon expulsion threshold increase from 0.49%to 0.87%.Types I and II_(1)source rocks are characterized by earlier hydrocarbon generation,more rapid hydrocarbon expulsion,and narrower hydrocarbon generation windows than types II_(2)and III source *** kerogen types also affect the HGE history and resource *** types(conventional,tight,and shale oil/gas)and three levels(realistic,expected,and prospective)of hydrocarbon resources of different members in the Liaohe Western Depression are *** suggest that t

关键词： Kerogen type Hydrocarbon generation potential Lacustrine source rocks Liaohe western depression

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提示工程师:概念、胜任力与成长路径

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高等工程教育研究 2024年第4期 21-30页

作者：符杰清华大学教育研究院、联合国教科文组织国际工程教育中心

随着大语言模型(LLM)及生成式人工智能技术的迅猛发展,提示工程师这一新兴职业应运而生。提示工程师专注于设计与优化用以引导大语言模型的提示(prompt),以提升模型的性能和适用性。首先梳理提示工程相关的基本概念,如自然语言处理、大... 详细信息

随着大语言模型(LLM)及生成式人工智能技术的迅猛发展,提示工程师这一新兴职业应运而生。提示工程师专注于设计与优化用以引导大语言模型的提示(prompt),以提升模型的性能和适用性。首先梳理提示工程相关的基本概念,如自然语言处理、大语言模型、生成式人工智能、提示等。然后细致阐述提示工程师的工作流程等,如问题定义、需求分析、提示设计、优化等。进一步,总结提示工程师的核心胜任力,包括硬技能和软技能,如深入理解自然语言处理、掌握提示技术、数据分析能力、编程能力、创造性思维、批判性思维与终身学习能力等,同时介绍提示工程师的几种常见工作场景及其应用实例。更进一步,论述提示工程师的成长路径。最后,讨论高等教育应当如何支持提示工程师的培养,包括建立面向人工智能的适应性课程体系;创新“AI+”教育模式,加强跨学科、实践导向的教学;深化校企产学研合作;提供终身学习资源,加强职业指导等。

关键词：提示工程师生成式人工智能胜任力 ChatGPT 大语言模型(LLM)

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Role of deubiquitinase JOSD2 in the pathogenesis of esophageal squamous cell carcinoma

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World Journal of Gastroenterology 2024年第6期30卷 565-578页

作者： Wen-Peng Wang Dan Shi Duo Yun Jun Hu jie-fu Wang Jia Liu Yan-Peng Yang Ming-Rui Li Jun-FengWang Da-Lu Kong Department of Colorectal Oncology Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerTianjin’s Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjin 300060China Department of Gastrointestinal Surgery Tianjin Nan Kai HospitalTianjin Medical UniversityTianjin Key Laboratory of Acute Abdomen Disease Associated Organ Injury and ITCWM RepairInstitute of Integrative Medicine for Acute Abdominal DiseasesTianjin 300100China Department of Oncology The First Hospital of HohhotHohhot 010000Inner Mongolia Autonomous RegionChina Department of Endocrinology Dazhou Central HospitalDazhou 635000Sichuan ProvinceChina

BACKGROUND Esophageal squamous cell carcinoma(ESCC)is a deadly malignancy with limited treatment ***(DUBs)have been confirmed to play a crucial role in the development of malignant ***2 is a DUB involved in con-trolling protein deubiquitination and influencing critical cellular processes in *** To investigate the impact of JOSD2 on the progression of *** Bioinformatic analyses were employed to explore the expression,prognosis,and enriched pathways associated with JOSD2 in *** transduction was utilized to manipulate JOSD2 expression in ESCC cell lines(KYSE30 and RESULTS )Preliminary research indicated that JOSD2 was highly expressed in ESCC tissues,which was associated with poor *** analysis demonstrated that JOSD2 was upregulated in ESCC cell lines compared to normal esophageal ***2 knockdown inhibited ESCC cell activity,including proliferation and colony-forming ***,JOSD2 knockdown decreased the drug resistance and migration of ESCC cells,while JOSD2 overexpression enhanced these *** vivo xenograft assays further confirmed that JOSD2 promoted tumor proliferation and drug resistance in ***,JOSD2 appears to activate the MAPK/ERK and PI3K/AKT signaling *** spectrometry was used to identify crucial substrate proteins that interact with JOSD2,which identified the four primary proteins that bind to JOSD2,namely USP47,IGKV2D-29,HSP90AB1,and *** JOSD2 plays a crucial role in enhancing the proliferation,migration,and drug resistance of ESCC,suggesting that JOSD2 is a potential therapeutic target in ESCC.

关键词： Esophageal squamous cell carcinoma JOSD2 Ubiquitination Biomarker Targeted therapy Drug resistance

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Characteristics and origin of low-organicmatter carbonate source rocks in the Middle-Upper Ordovician, Tarim Basin, northwestern China

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Journal of Palaeogeography 2024年第3期13卷 594-619页

作者： Jun-Qing Chen fu-jie Jiang Xiong-Qi Pang Hai-Jun Yang Kan-Yuan Shi Bo Pang Hong Pang Jian-Fa Chen Zhuo-Heng Chen Xin-Gang Zhang Song Wu State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing 102249China Basic Research Center for Energy Interdisciplinary College of ScienceChina University of Petroleum(Beijing)Beijing 102249China Beijing Key Laboratory of Optical Detection Technology for Oil and Gas China University of Petroleum(Beijing)Beijing 102249China College of Geosciences China University of Petroleum(Beijing)Beijing 102249China Research Institute of Petroleum Exploration and Development PetroChina Tarim Oilfield CompanyKorla 841000Xinjiang Uygur Autonomous RegionChina Geological Survey of Canada Natural Resources CanadaCalgary T2L 2A7Canada

The continually-discovered large volumes of marine hydrocarbons indicate a huge exploration potential within the carbonate rocks of Ordovician in the Tarim Basin,northwestern *** Middle-Upper Ordovician(O2+3)carbonate source rocks are at a highly mature *** rocks presently contain a low amount of total organic carbon(TOC_(pd)≤0.5%)(TOC_(pd) means the present-day TOC).A mass balance approach is used to identify the source rocks that have expelled *** characteristics and origin of hydrocarbon expulsion from low-TOC_(pd) source rocks are studied,which are significant for oil exploration in the *** results showed that a low-TOC_(pd) O2+3 source rock having expelled hydrocarbons was type I and had a very narrow oil *** a high rock maturity and a high original TOC(TOCo)value exceeding 1%,nearly 80%of the generated hydrocarbons were *** content of gammacerane and C28 steranes in the oil and source rock extracts were relatively lean,with a V-shaped distribution of regular steranes,suggesting a possible genetic relation between the low-TOC_(pd) source rocks and the marine oil in the Tabei *** planktonic algae or acritarchs were the main hydrocarbon parent materials,distributed in the subsiding platform-slope *** matter was preserved under reducing conditions,and source rocks were formed with a favorable kerogen type and a moderate hydrocarbon generation *** study illustrates the hydrocarbon expulsion of low TOC_(pd) source rocks in northern Tarim Basin,which is greatly significant for analyzing the genesis of marine crude oil in Tarim Basin,and evaluating the distribution of marine source *** research method is theoretically significant for oil and gas exploration in the same type of highlymature carbonate paleobasins.

关键词： Carbonate source rock Mass balance approach Present-day TOC Genesis mechanism Tarim Basin

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世界一流工科大学跨学科性探析:基于Web of Science近50年数据的研究

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高教探索 2024年第5期 53-65页

作者：符杰清华大学教育研究院联合国教科文组织国际工程教育中心北京/100084

世界一流大学的跨学科性是产生重大原始创新成果和培养跨学科人才的重要基础。然而,评估测量大学的跨学科性一直是个难题。选取麻省理工学院、帝国理工学院、亚琛工业大学、东京工业大学和清华大学五所以理工科见长的世界一流大学为研... 详细信息

世界一流大学的跨学科性是产生重大原始创新成果和培养跨学科人才的重要基础。然而,评估测量大学的跨学科性一直是个难题。选取麻省理工学院、帝国理工学院、亚琛工业大学、东京工业大学和清华大学五所以理工科见长的世界一流大学为研究对象,尝试改进了一种基于Web of Science学科分类的大学跨学科性测量方法,基于近50年的数据测量分析五所大学的学科广度、学科分布与跨学科性及其变化趋势,并用可视化方式呈现研究结果。研究发现世界一流工科大学学科生态日趋复杂,学科分布同中有异,其分布的异同表明当前世界科学发展的多样性,也体现各个大学的学科发展特色。世界一流大学的跨学科性差异与其跨学科发展战略密不可分。建议我国“双一流”建设高校应根据自身所处学科建设发展阶段,制定学科建设战略目标,形成具有本校特色的跨学科发展战略,打造良好的跨学科生态系统。

关键词：世界一流工科大学工程教育跨学科学科建设实证研究

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Src inhibition rescues fuNDC1-mediated neuronal mitophagy in ischaemic stroke

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Stroke & Vascular Neurology 2024年第4期9卷 367-379,I0022-I0031页

作者： Tianchi Tang Li-bin Hu Chao Ding Zhihua Zhang Ning Wang Tingting Wang Hang Zhou Siqi Xia Linfeng Fan Xiong-jie fu Feng Yan Xiangnan Zhang Gao Chen Jianru Li Department of Neurosurgery Zhejiang University School of Medicine Second Affiliated HospitalHangzhouZhejiangChina 2NeurosurgeryZhejiang University School of Medicine Second Affiliated HospitalHangzhouZhejiangChina 3Zhejiang University School of MedicineHangzhouZhejiangChina 4Zhejiang University Department of PharmacologyHangzhouZhejiangChina

Background Ischaemic stroke triggers neuronal mitophagy,while the involvement of mitophagy receptors in ischaemia/reperfusion(I/R)injury-induced neuronal mitophagy remain not fully ***,we aimed to investigate the involvement of mitophagy receptor fuN14 domain-containing 1(fuNDC1)and its modulation in neuronal mitophagy induced by I/R *** Wild-type and fuNDC1 knockout mice were generated to establish models of neuronal I/R injury,including transient middle cerebral artery occlusion(tMCAO)in vivo and oxygen glucose deprivation/reperfusion in *** outcomes of mice with two genotypes were *** mitophagy was analysed both in vivo and in *** of fuNDC1 and its regulator Src were *** impact of Src on fuNDC1-mediated mitophagy was assessed through administration of Src antagonist *** To our surprise,fuNDC1 knockout mice subjected to tMCAO showed stroke outcomes comparable to those of their wild-type *** neuronal mitophagy could be activated by I/R injury,fuNDC1 deletion did not disrupt neuronal *** activation of fuNDC1,represented by dephosphorylation of Tyr18,was detected in the early stages(within 3hours)of neuronal I/R injury;however,phosphorylated Tyr18 reappeared and even surpassed baseline levels in later stages(after 6hours),accompanied by a decrease in fuNDC1-light chain 3 *** inactivation of fuNDC1 was associated with Src activation,represented by phosphorylation of Tyr416,which changed in parallel with the level of phosphorylated fuNDC1(Tyr18)during neuronal I/R ***,fuNDC1-mediated mitophagy in neurons under I/R conditions can be rescued by pharmacological inhibition of *** fuNDC1 is inactivated by Src during the later stage(after 6hours)of neuronal I/R injury,and rescue of fuNDC1-mediated mitophagy may serve as a potential therapeutic strategy for treating ischaemic stroke.

关键词： fuNDC1 involvement injury

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