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Syntheses of new di-nuclear and tetra-nuclear lanthanide 9-anthracenecarboxylates:Magnetocaloric effect,slow magnetic relaxation and luminescent properties

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Journal of Rare Earths 2024年第6期42卷 1101-1109,I0004页

作者： Xing Liu ruonan yang Lu Zhang Jian Zhou Chunmei Huang Huahong Zou Zunhong Xiao Chongqing Key Laboratory of Inorganic Functional Materials College of ChemistryChongqing Normal UniversityChongqing401331China Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources(Ministry of Education of China) School of Chemistry and Chemical Engineering of Guangxi Normal UniversityGuilin541004China School of Chemistry and Materials Guizhou Normal UniversityGuiyang550025China

Lanthanide complex-based materials with magnetic and luminescent properties have received a great deal of attention,owing to their importantly potential applications in diverse *** this work,the 9-anthracenecarboxylic acid(9-Haca)as bridging ligand was applied in combination with optically activeπ-conjugated 2,4,6-tri(2-pyridyl)-1,3,5-triazine(tptz)to construct a series of new di-nuclear and tetranuclear lanthanide 9-anthracenecarboxylates[La_(2)(9-aca)_(6)(tptz)_(2)(μ-H_(2)O)]·0.25H_(2)O(1),[Ln_(2)(9-aca)_(6)(tptz)_(2)(H_(2)O)_(2)]·0.5AQ·CH_(3)COOH_(2)H_(2)O[Ln=Sm(2a),Eu(2b),Gd(2c),Tb(2d),Dy(2e),Tm(2f);AQ=9,10-anthracenedione]and[Ln_(4)(9-aca)_(10)(tptz)_(2)(CH3COO)2]·H_(2)O[Ln=Eu(3a),Gd(3b),Dy(3c)].1 displays a di-nuclear centrosymmetric moiety[La_(2)(9-aca)_(6)(tptz)_(2)(μ-H_(2)O)]built up from two complex[La(9-aca)_(2)(tptz)]groups bridged by one H_(2)O molecule and two syn-syn-μ2-η1:η1-9-aca-bridging ligands,while 2a-2f are isostructural and co mprise another di-nuclear centrosymmetric moieties[Ln_(2)(9-aca)_(6)(tptz)_(2)(H_(2)O)_(2)]based on two complex[Ln(9-aca)_(2)(tptz)(H_(2)O)]groups connected by two syn-syn-μ2-η1:η1-9-aca-bridging ligands,3a-3c are isostructural and show tetra-nuclear centro symmetric moieties[Ln4(9-aca)10(tptz)2(CH3COO)2]containing three types of coordination modes of *** present compounds offer the only examples of lanthanide 9-anthracenecarboxylates decorated by optically active *** investigations of 2a,2c-2f,and 3b-3c indicate that 3c is typical of slow relaxation of the magnetization,while 2c and 3b show significant magnetocaloric effect(MCE)with the value of-ΔSm of 5.26 J/(kg·K)at 4 K and 15.65 J/(kg·K)at 2 K(ΔH=7 T),*** luminescent properties were also studied and reveal that the characteristic luminescent properties of the 7r-conjugated aromatic ligands are introduced into magnetic lanthanide 9-anthracenecarboxylates,simultaneously exhibiting slow magnetic relaxation(or MCE)and luminescen

关键词： Lanthanide complexes Luminescence Magnetic properties Magnetocaloric effect Slow magnetic relaxation Rare earths

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Pd cluster decorated free standing flexible cathode for high performance Li-oxygen batteries

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Nano Research 2024年第4期17卷 2678-2686页

作者： Liang Guo Guoliang Zhang ruonan yang Dongmei Zhang Xiuqi Zhang Han Yu Xia Li Feng Dang Key Laboratory for Liquid-Solid Structure Evolution and Processing of Materials Ministry of EducationShandong UniversityJinan 250061China

As a promising candidate for the next generation energy storage system,rechargeable lithium-oxygen batteries(LOBs)still face substantial challenges caused by insulating discharge products that preclude their practical *** highly efficient cathode catalysts capable of facilitating formation/decomposition of discharge products is considered as an essential approach towards high performance ***,Pd decorated Te nanowires(Pd@Te NWs)were synthesized as advanced catalyst in LOBs to maximize Pd utilization and achieve synergistic effect,in which Pd clusters were uniformly grown on Te substrate though regulating the Pd:Te ***,Pd@Te nanowires assembled into an interpenetrating network-like structure by vacuum filtration and employed as flexible cathode,enabling LOBs achieved an ultralong 190 cycles stability and a superior specific capacity of 3.35 mAh·cm^(-2).Experimental studies and density functional theory(DFT)calculations reveal the excellent catalytic ability of Pd@Te and synergistic catalytic mechanism of Pd and Te,in which uniform electron distribution,extensive electron exchange,and large adsorption distance between Pd cluster and discharge products promote homogeneous adsorption/desorption of discharge products,while the high adsorption energy of Te substrate for Li species reduces the initial dynamical energy barrier during discharging *** current work provides viable strategy to design composite catalysts for flexible cathode of LOBs with synergistic catalytic effects.

关键词： flexible lithium-oxygen batteries Pd@Te synergistic catalysis cathode catalysts density functional theory(DFT)calculation

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热挤压和热处理对铀-2.1%钼合金组织结构特性的影响

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金属热处理 2024年第6期49卷 183-189页

作者：杜继军郭洪徐勇贺进明李波杨若楠中核新型材料研究与应用开发重点实验室内蒙古包头014035 中核北方核燃料元件有限公司内蒙古包头014035 山东建筑大学材料科学与工程学院山东济南250101

采用显微组织结构分析技术,对含钼量2.1%的铀钼合金在热挤压、扩散性退火、淬火、回火等工艺条件下的物相结构、组成和显微组织特征等进行了研究。结果表明,铀钼合金经不同的热加工工艺处理,其组织结构会有较大的变化。热挤压工艺对铀... 详细信息

采用显微组织结构分析技术,对含钼量2.1%的铀钼合金在热挤压、扩散性退火、淬火、回火等工艺条件下的物相结构、组成和显微组织特征等进行了研究。结果表明,铀钼合金经不同的热加工工艺处理,其组织结构会有较大的变化。热挤压工艺对铀钼合金的物相组成影响不大,但对物相结构和组织特征会带来明显改变,可增加合金的硬度和强度。淬火工艺对铀钼合金的物相组成、结构和显微组织均有明显的影响,其组织结构转变为接近α相结构的α′b单相马氏体,可造成合金的硬度和强度明显增加,但塑性和韧性将会降低。扩散性退火和回火工艺,会消除应力应变或快速相变带来的物相结构、组成和显微组织特征的影响,恢复到均匀化退火状态下的相关组织结构特性,可改善合金的塑性和韧性。

关键词：铀钼合金热挤压热处理显微组织物相组成相结构

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基于1990—2020年综合土地利用动态变化的巩义市城市边缘区空间研究

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林业调查规划 2024年第2期49卷 6-12页

作者：黄懿杨若楠冯艳河南农业大学河南郑州450002 河南省城乡规划设计研究总院股份有限公司河南郑州450044

以郑州市下辖且接壤的巩义市为研究对象,以1990年和2020年两期TM/OLI影像和统计年鉴数据为依据,使用1 km×1 km网格划分样区并提取各样区的综合土地利用动态度数值,借助数学模型分析确定城市边缘区范围,分析巩义市近30年来城市边缘区用... 详细信息

以郑州市下辖且接壤的巩义市为研究对象,以1990年和2020年两期TM/OLI影像和统计年鉴数据为依据,使用1 km×1 km网格划分样区并提取各样区的综合土地利用动态度数值,借助数学模型分析确定城市边缘区范围,分析巩义市近30年来城市边缘区用地变化特征及扩展机制。结果表明,自然条件是用地扩张的基础因素,政策与经济是边缘区外扩的核心驱动力,交通对扩张具有指向性作用;边缘区内的土地变化主要表现为建设用地急剧增加、农业用地锐减,同时受距离和开发时序影响,用地类型交错复杂,破碎化特征明显。

关键词：城市边缘区遥感影像综合土地利用动态度土地扩展机制

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不同生物调节剂处理对沾化冬枣产量和品质的影响

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果树资源学报 2024年第4期5卷 12-14页

作者：杨若楠盖志君滨州市政务服务中心山东滨州256600 滨州市滨城区政务服务中心山东滨州256600

【目的】明确不同生物调节剂处理对沾化冬枣产量和品质的影响,以提高沾化冬枣产量和品质,促进农户增产增收。【方法】于2022年开展田间实验,设置清水对照(CK)、喷施生物调节剂赤霉酸(T1)、喷施生物调节剂氯吡脲(T2)和喷施生物调节剂芸... 详细信息

【目的】明确不同生物调节剂处理对沾化冬枣产量和品质的影响,以提高沾化冬枣产量和品质,促进农户增产增收。【方法】于2022年开展田间实验,设置清水对照(CK)、喷施生物调节剂赤霉酸(T1)、喷施生物调节剂氯吡脲(T2)和喷施生物调节剂芸苔素内酯(T3)4种处理,对不同生物调节剂处理后沾化冬枣的产量、产量构成因素指标以及可滴定酸、维生素C等果实品质指标进行分析,筛选出沾化地区冬枣种植的最优生物调节剂。【结果】结果表明,生长调节剂赤霉酸、氯吡脲和芸苔素内酯可以显著减少沾化冬枣落花落果情况的出现,同时提升冬枣产量指标(冬枣单果质量、果实横径、果实纵径和产量)与品质指标(可溶性糖质量分数和维生素C含量),可在当地冬枣种植生产中进行推广应用。【结论】研究结果可为生物调节剂在沾化地区冬枣种植中的应用提供理论依据。

关键词：沾化冬枣生物调节剂产量果实品质

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生命健康科技领域发展态势

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中国生物工程杂志 2024年第1期44卷 32-40页

作者：许丽杨若南王玥施慧琳李祯祺靳晨琦李伟徐萍中国科学院上海营养与健康研究所中国科学院上海生命科学信息中心上海200031

生命健康科技领域是新一轮科技革命和产业变革中最有望实现革命性突破的重点领域之一。随着学科和技术会聚融合,生命健康科技显现出了新的发展趋势,衍生了新学科、新方向、新前沿,创造了新的产业细分领域和增长点。近几年,生命健康科技... 详细信息

生命健康科技领域是新一轮科技革命和产业变革中最有望实现革命性突破的重点领域之一。随着学科和技术会聚融合,生命健康科技显现出了新的发展趋势,衍生了新学科、新方向、新前沿,创造了新的产业细分领域和增长点。近几年,生命健康科技领域创新活跃,基因编辑、合成生物学、生命组学、再生医学、类器官等前沿领域的重大成果密集涌现。在深入分析生命健康科技领域当前值得特别关注的发展趋势及前沿方向的基础上,展望生命健康科技领域未来发展前景并提出重点布局方向,以期为生命健康领域科技创新发展提供参考。

关键词：生命健康基因编辑合成生物学生命组学类器官

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Microbial phenolic metabolites 3-(3',4'-dihydroxyphenyl)propanoic acid and 3',4'-dihydroxyphenylacetic acid prevent obesity in mice fed high-fat diet

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Food Science and Human Wellness 2024年第1期13卷 327-338页

作者： Wanbing Chen ruonan Liu Xiaoling Zhu Qun Lu Hong yang Rui Liu College of Food Science and Technology Huazhong Agricultural UniversityWuhan 430000China Key Laboratory of Environment Correlative Dietology(Huazhong Agricultural University) Ministry of educationWuhan 430000China Wuhan Engineering Research Center of Bee Products on Quality and Safety Control Wuhan 430000China Key Laboratory of Urban Agriculture in Central China Ministry of Agriculture and Rural AffairsWuhan 430000China Hubei Provincial Institute for Food Supervision and Test Wuhan 430070China

Obesity is associated with numerous metabolic disorders,and dietary polyphenols have been confirmed to have beneficial effects on the metabolism in ***,the effect of 3-(3’,4’-dihydroxyphenyl)propanoic acid(DHPA)and 3’,4’-dihydroxyphenylacetic acid(DHAA),two main metabolites of dietary polyphenols,on obesity remains poorly *** this study,DHPA and DHAA were found to alleviate obesity,as well as regulate insulin resistance,lipid metabolism,and oxidative stress response in high-fat diet(HFD)***,the 16S rRNA sequencing and UHPLC-Q-TOF/MS demonstrated that DHPA and DHAA only slightly disturbed the intestinal microbiome,but significantly altered the urine metabolome of HFD mice mainly by regulating pentose and glucuronate interconversion,tyrosine metabolism,pentose phosphate and tricarboxylic acid(TCA)cycle as indicated by metabolic pathway analysis based on Kyoto Encyclopedia of Genes and Genomes(KEGG)*** analysis revealed that the differential metabolites are strongly associated with body weight,blood glucose,insulin level,and superoxide dismutase(SOD)enzyme *** results revealed that DHPA and DHAA exert their anti-obesity effect by regulating important metabolites in the glucose,lipid and tyrosine metabolism pathways.

关键词： Obesity Dietary polyphenol metabolites Gut microbiota Metabonomics

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Joint position optimization,user association,and resource allocation for load balancing in UAV-assisted wireless networks

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Digital Communications and Networks 2024年第1期10卷 25-37页

作者： Daosen Zhai Huan Li Xiao Tang ruonan Zhang Haotong Cao School of Electronics and Information Northwestern Polytechnical UniversityXian710072China State Key Laboratory of Integrated Services Networks Xidian UniversityXian710071China Department of Computing Hong Kong Polytechnic UniversityHong Kong SARChina

Unbalanced traffic distribution in cellular networks results in congestion and degrades spectrum *** tackle this problem,we propose an Unmanned Aerial Vehicle(UAV)-assisted wireless network in which the UAV acts as an aerial relay to divert some traffic from the overloaded cell to its adjacent underloaded *** fully exploit its potential,we jointly optimize the UAV position,user association,spectrum allocation,and power allocation to maximize the sum-log-rate of all users in two adjacent *** tackle the complicated joint optimization problem,we first design a genetic-based algorithm to optimize the UAV ***,we simplify the problem by theoretical analysis and devise a low-complexity algorithm according to the branch-and-bound method,so as to obtain the optimal user association and spectrum allocation *** further propose an iterative power allocation algorithm based on the sequential convex approximation *** simulation results indicate that the proposed UAV-assisted wireless network is superior to the terrestrial network in both utility and throughput,and the proposed algorithms can substantially improve the network performance in comparison with the other schemes.

关键词： Load balance Unmanned aerial vehicle Userassociation Resource management

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Potential evaluation and implementation strategy for pocket park construction in high-density urban areas: A case study in Dalian, China

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Frontiers of Architectural Research 2024年第2期13卷 319-334页

作者： Jing Dong ruonan Guo Fei Guo Jun Cai School of Architecture and Fine Art Dalian University of TechnologyDalian 116024China

As an important element of urban renewal in highly urbanized areas, pocket parks with small size, flexible layout and daily accessibility are becoming a major component of green infrastructure and the mainstay of outdoor recreation space expansion in high-density urban centers. Nevertheless, the absence of a comprehensive framework for evaluating the potential of pocket park construction (PPC), one that integrates diverse influencing factors on a macro scale, has resulted in the random installation of such spaces, often failing to optimize the utilization of urban land. Addressing this critical lacuna, we propose an approach to evaluate PPC potential from a city-scale perspective, which is used to support the determination of which land units should be prioritized for PPC. A complete and feasible workflow was also established to identify potential land units, construct an index system for PPC combining demand and supply levels, quantitatively calculate indices based on remote sensing (RS) and geographic information system (GIS), accurately evaluate PPC potential using an entropy-weighted TOPSIS model, and develop targeted renewal strategies. A case study in Dalian, China, demonstrated the applicability and implications of the workflow. The results showed that it is flexible and easy to adapt to different local contexts, allowing evaluators to introduce parameters considering the availability of local data, and will help decision makers to build pocket parks in the most effective plots, providing a strong reference for high-quality development in other high-density urban centers facing the contradiction between ecological construction and land scarcity.

关键词： Pocket park Potential evaluation Urban renewal High-density urban areas

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Impact of short-term ambient air pollution exposure on the risk of severe COVID-19

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Journal of Environmental Sciences 2024年第1期135卷 610-618页

作者： Baihuan Feng Jiangshan Lian Fei Yu Dan Zhang Weizhen Chen QiWang Yifei Shen Guoliang Xie ruonan Wang Yun Teng Bin Lou Shufa Zheng Yida yang Yu Chen Department of Laboratory Medicine The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310000China Key Laboratory of Clinical In Vitro Diagnostic Techniques of Zhejiang Province Hangzhou 310000China Institute of Laboratory Medicine Zhejiang UniversityHangzhou 310000China Department of Infectious Diseases The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310000China State Key Laboratory for Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious Diseasesthe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310000China

Ecological studies suggested a link between air pollution and severe COVID-19 outcomes,while studies accounting for individual-level characteristics are *** the present study,we aimed to investigate the impact of short-term ambient air pollution exposure on disease severity among a cohort of 569 laboratory confirmed COVID-19 patients admitted to designated hospitals in Zhejiang province,China,from January 17 to March 3,2020,and elucidate the possible biological processes involved using *** with mild cases,severe cases had higher proportion of medical conditions as well as unfavorable results in most of the laboratory tests,and manifested higher air pollution exposure *** exposure to air pollutants was associated with increased risk of severe COVID-19 with odds ratio(OR)of 1.89(95%confidence interval(CI):1.01,3.53),2.35(95%CI:1.20,4.61),2.87(95%CI:1.68,4.91),and 2.01(95%CI:1.10,3.69)for PM_(2.5),PM_(10),NO_(2)and CO,*** for NO_(2)remained significant in two-pollutant models after adjusting for other *** analysis showed 884 differentially expressed genes which mainly were enriched in virus clearance related biological processes between patients with high and low NO_(2)exposure levels,indicating that compromised immune response might be a potential underlying mechanistic *** findings highlight the impact of shortterm air pollution exposure,particularly for NO_(2),on COVID-19 severity,and emphasize the significance in mitigating the COVID-19 burden of commitments to improve air quality.

关键词： Air pollution COVID-19 Severity Transcriptomics Immune response

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