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In-situ formation of nitrogen doped microporous carbon nanospheres derived from polystyrene as lubricant additives for anti-wear and friction reduction

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Friction 2024年第3期12卷 439-451页

作者： Yixin WANG Qi LU Huijie XIE Shujuan LIU qian ye Feng ZHOU Weimin LIU State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

This study presents a nitrogen-doped microporous carbon nanospheres(N@MCNs)prepared by a facile polymerization–carbonization process using low-cost styrene.The N element in situ introduces polystyrene(PS)nanospheres via emulsion polymerization of styrene with cyanuric chloride as crosslinking agent,and then carbonization obtains N@MCNs.The as-prepared carbon nanospheres possess the complete spherical structure and adjustable nitrogen amount by controlling the relative proportion of tetrachloromethane and cyanuric chloride.The friction performance of N@MCNs as lubricating oil additives was surveyed utilizing the friction experiment of ball-disc structure.The results showed that N@MCNs exhibit superb reduction performance of friction and wear.When the addition of N@MCNs was 0.06 wt%,the friction coefficient of PAO-10 decreased from 0.188 to 0.105,and the wear volume reduced by 94.4%.The width and depth of wear marks of N@MCNs decreased by 49.2% and 94.5%,respectively.The carrying capacity of load was rocketed from 100 to 400 N concurrently.Through the analysis of the lubrication mechanism,the result manifested that the prepared N@MCNs enter clearance of the friction pair,transform the sliding friction into the mixed friction of sliding and rolling,and repair the contact surface through the repair effect.Furthermore,the tribochemical reaction between nanoparticles and friction pairs forms a protective film containing nitride and metal oxides,which can avert direct contact with the matrix and improve the tribological properties.This experiment showed that nitrogen-doped polystyrene-based carbon nanospheres prepared by in-situ doping are the promising materials for wear resistance and reducing friction.This preparing method can be ulteriorly expanded to multi-element co-permeable materials.Nitrogen and boron co-doped carbon nanospheres(B,N@MCNs)were prepared by mixed carbonization of N-enriched PS and boric acid,and exhibited high load carrying capacity and good tribological properties.

关键词： lubricant additives hypercrosslinked polystyrene carbon nanospheres friction reduction anti-wear

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The influence of different functional areas on customers’thermal comfort-A Field study in shopping complexes of North China

Energy and Built Environment

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Energy and Built Environment 2023年第3期4卷 297-307页

作者： Xingyu Zang Kuixing Liu ye qian Guanhua Qu ye Yuan Lei Ren Gang Liu Tianjin International Engineering Institute Tianjin UniversityTianjin 300072China School of Architecture Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Architectural Physical Environment and Ecological Technologies Tianjin UniversityTianjin 300072China

Shopping complexes are widely built for their convenience and multiple functions.However,their complex func-tional areas,result in significantly different thermal environments and various customers’thermal perception.To explain the influence of functional related parameters on the thermal perception of customers in shopping com-plexes,we selected two typical functional related parameters,including customers’thermal expectation level of indoor environment in their current area and the area where the customer was ten minutes before taking the sur-vey.851 valid questionnaires were obtained in two typical shopping complexes during July.Customers’thermal neutral temperature,thermal preference temperature and thermal comfort temperature range were calculated in different functional areas.Customers’thermal expectation level was quantified by using expectancy factor.The results showed that customers’thermal expectation level in entertainment areas was the highest,followed by food courts,retail areas,and transition spaces.Customers’thermal expectation level would influence their thermal neutral temperature and thermal sensitivity.Customers with different thermal experience differed sig-nificantly in their thermal sensation voting(p<0.01).The highest thermal sensitivity,about 0.41/°C,was found in customers moving from high-temperature areas to low-temperature areas.These findings help to clarify how functional related parameters affect the thermal comfort of customers and provide the guidance for designing the indoor temperature in shopping complexes.

关键词： Shopping complexes Field study Thermal comfort Thermal expectation level Expectancy factor Thermal experience

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Dietary bamboo leaf flavonoids improve quality and microstructure of broiler meat by changing untargeted metabolome

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Journal of Animal Science and Biotechnology 2023年第4期14卷 1514-1527页

作者： Guangtian Cao Huixian Wang Yang Yu Fei Tao Huijuan Yang Shenglan Yang ye qian Hui Li Caimei Yang College of Standardisation China Jiliang UniversityHangzhou 310018People’s Republic of China Key Laboratory of Applied Technology On Green-Eco-Healthy Animal Husbandry of Zhejiang Province Zhejiang Provincial Engineering Laboratory for Animal Health and Internet TechnologyCollege of Animal Science and TechnologyZhejiang A&F UniversityHangzhou 311300People’s Republic of China Zhejiang Vegamax Biotechnology Co. Ltd.Anji 313300People’s Republic of China

Background Dietary bamboo leaf flavonoids(BLFs)are rarely used in poultry production,and it is unknown whether they influence meat texture profile,perceived color,or microstructure.Results A total of 720 one-day-old Arbor Acres broilers were supplemented with a basal diet with 20 mg bacitracin/kg,50 mg BLFs/kg,or 250 mg BLFs/kg or without additions.Data showed that the dietary BLFs significantly(P<0.05)changed growth performance and the texture profile.In particular,BLFs increased birds’average daily gain and average daily feed intake,decreased the feed:gain ratio and mortality rate,improved elasticity of breast meat,enhanced the gumminess of breast and leg meat,and decreased the hardness of breast meat.Moreover,a significant(P<0.05)increase in redness(a*)and chroma(c*)of breast meat and c*and water-holding capacity of leg meat was found in BLF-supplemented broilers compared with control broilers.In addition,BLFs supplementation significantly decreased(P<0.05)theβ-sheet ratio and serum malondialdehyde and increased theβ-turn ratio of protein secondary structure,superoxide dismutase,and glutathione peroxidase of breast meat and total antioxidant capacity and catalase of serum.Based on the analysis of untargeted metabolome,BLFs treatment considerably altered 14 metabolites of the breast meat,including flavonoids,amino acids,and organic acids,as well as phenolic and aromatic compounds.Conclusions Dietary BLFs supplementation could play a beneficial role in improving meat quality and sensory color in the poultry industry by changing protein secondary structures and modulating metabolites.

关键词： Bamboo leaf flavonoid Broiler Meat quality Metabolome Protein secondary structure

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Late Cretaceous K-rich rhyolitic crystal tuffs from the Chuduoqu area in Eastern qiangtang subterrane:evidence for crustal thickening of the central Tibetan Plateau prior to India–Asia collision

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Acta Geochimica 2022年第1期41卷 147-163页

作者： Yonggang Sun Bile Li Fengyue Sun Qingfeng Ding Junlin Dong ye qian Yujin Li Zhen Yao College of Earth Sciences Jilin University2199 Jianshe StreetChangchun 130061China College of Mining Liaoning Technical UniversityFuxin 123000China No.5 Geologic Exploration Institute of Qinghai Province Xining 810003China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Land and ResourcesChangchun 130061China

In order to constrain whether the Lhasa–qiangtang collision contributed to an early crustal thickening of the central Tibetan Plateau prior to the India–Asia collision,we present zircon LA–ICP–MS U–Pb ages,wholerock geochemistry,and zircon Hf isotopic compositions of the newly discovered rhyolitic crystal tuffs from the Chuduoqu area in the eastern qiangtang subterrane,central Tibet.Zircon U–Pb dating suggests that the Chuduoqu rhyolitic crystal tuffs were emplaced at ca.68 Ma.The Chuoduoqu rhyolitic crystal tuffs display high SiO_(2) and K2 O,and low MgO,Cr,and Ni.Combined with their zircon Hf isotopic data,we suggest that they were derived from partial melting of the juvenile lower crust,and the magma underwent fractional crystallization and limited upper continental crustal assimilation during its evolution prior to eruption.They should be formed in a post-collisional environment related to lithospheric mantle delamination.The Chuduoqu rhyolitic crystal tuffs could provide important constraints on the Late Cretaceous crustal thickening of the central Tibetan Plateau caused by the Lhasa–qiangtang collision.

关键词： Rhyolitic crystal tuffs Late Cretaceous Crustal thickening Lhasa-qiangtang collision Central Tibetan Plateau

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Corvis ST新参数应力-应变指数的研究进展

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国际眼科杂志 2024年第1期24卷 97-100页

作者：叶倩张红凉山州第一人民医院眼科中国四川省西昌市614400 云南大学附属医院眼科中国云南省昆明市650000

可视化角膜生物力学分析仪(Corvis ST)是目前评估在体角膜生物力学最常用的临床设备。新参数应力-应变指数(SSI)是近年来临床研究的热点,其不仅可以直接反映角膜生物材料刚度,而且与某些疾病的进展密切相关。SSI是基于使用有限元(FE)数... 详细信息

可视化角膜生物力学分析仪(Corvis ST)是目前评估在体角膜生物力学最常用的临床设备。新参数应力-应变指数(SSI)是近年来临床研究的热点,其不仅可以直接反映角膜生物材料刚度,而且与某些疾病的进展密切相关。SSI是基于使用有限元(FE)数值建模模拟眼内压和Corvis ST喷气效果的角膜行为预测生成的。SSI算法不随着本身中央角膜厚度(CCT)、眼内压以及生物力学矫正眼压(BIOP)的变化而变化,但明显与角巩膜中的胶原纤维改变有关。本文将从SSI的原理、年龄与SSI的关系、眼轴与SSI的关系、近视程度与SSI的关系、SSI的应用等方面进行归纳和总结。

关键词：可视化角膜生物力学分析仪(Corvis ST) 应力-应变指数年龄眼轴近视

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Linkage and association mapping of wild soybean(Glycine soja)seeds germinating under salt stress

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Journal of Integrative Agriculture 2022年第10期21卷 2833-2847页

作者： SHI Mei-qi LIAO Xi-liang ye qian ZHANG Wei LI Ya-kai Javaid Akhter BHAT KAN Gui-zhen YU De-yue National Key Laboratory of Crop Genetics and Germplasm Enhancement National Center for Soybean ImprovementNanjing Agricultural UniversityNanjing 210095P.R.China Innovative Center of Molecular Genetics and Evolution School of Life SciencesGuangzhou UniversityGuangzhou 510405P.R.China

Salinity threatens soybean germination,growth and production.The germination stage is a key period in the life of soybean.Wild soybean contains many genes related to stress resistance that are valuable resources for the genetic improvement of soybean.To identify the genetic loci of wild soybean that are active during seed germination under salt stress,two populations,a soybean interspecific hybrid population comprising 142 lines and a natural population comprising 121 wild soybean accessions,were screened for three germination-related traits in this study.By using single-nucleotide polymorphism(SNP)markers with three salt tolerance indices,25 quantitative trait loci(QTLs),21 significant SNPs(–log_(10)(P)≥4.0)and 24 potential SNPs(3.5<–log_(10)(P)<4.0)were detected by linkage mapping and a genome-wide association study(GWAS)in two environments.The key genetic region was identified based on these SNPs and QTLs.According to the gene functional annotations of the W05 genome and salt-induced gene expression qRT-PCR analysis,GsAKR1 was selected as a candidate gene that responded to salt stress at the germination stage in the wild soybean.These results could contribute to determining the genetic networks of salt tolerance in wild soybean and will be helpful for molecular marker-assisted selection in the breeding of salt-tolerant soybean.

关键词： salt tolerance wild soybean QTLs GWAS GsAKR1

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Zircon U–Pb age and geochemical constraints on the origin and tectonic implication of the Tuotuohe Cenozoic alkaline magmatism in Qinghai–Tibet Plateau

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Acta Geochimica 2020年第1期39卷 67-84页

作者： ye qian Shengnan Tian Yujin Li Fengyue Sun College of Earth Sciences Jilin UniversityChangchunChina Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Natural Resources of the People's Republic of ChinaChangchunChina

A large number of Eocene-Oligocene alkaline/alkali-rich igneous rocks were developed in the Tuotuohe region of the Qinghai-Tibetan Plateau.In this study,we present zircon U-Pb ages,Hf isotope data,and major and trace element compositions of the Cenozoic alkaline rocks from the Tuotuohe region in order to constraint the petrogenesis and tectonic evolution history of qiangtang Block.Zircon U-Pb ages were measured via LA-ICP-MS to be39.6,37.6 and 32.0 Ma.The 39.6 Ma trachyte was characterized by low SiO2 and high K2O and MgO contents.The 37.6 and 32.0 Ma orthophyres show enrichment in SiO2 and K2O,but deficient in MgO.All of the samples belong to the alkaline rocks.These rocks display enrichment in REE,LREE,and LILE,depletion in HFSE,and no obvious Eu anomalies.Geological and geochemical features suggest that there were two possible mechanisms for the origin of the alkaline rocks in the Tuotuohe region:(1)the removed mafic lower crust dropped into the asthenosphere,forming the mix magma(Nariniya trachyte);(2)the upwelling asthenosphere triggered the crustal melting(Nariniya and Zamaqu orthophyre).The Eocene-Oligocene alkaline rocks in the study and adjacent areas are likely to be the result of the same tectonic-magmatic event of deep lithospheric evolution that is the crustal material melting triggered by lithospheric delamination.This conclusion extends the influence scope of lithospheric delamination eastward to the Tuotuohe region(*92°E)from Banda Co(*82°E).

关键词： Zircon U-Pb chronology Zircon Hf isotopic Delamination Tuotuohe region Qinghai–Tibetan Plateau

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Age and petrogenesis of late Mesozoic intrusions in the Huoluotai porphyry Cu-(Mo)deposit,northeast China:Implications for regional tectonic evolution

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Geoscience Frontiers 2022年第2期13卷 311-332页

作者： Yong-gang Sun Bi-le Li Zhong-hai Zhao Feng-yue Sun Qing-feng Ding Xu-sheng Chen Jie-biao Li ye qian Yu-jin Li College of Earth Sciences Jilin UniversityChangchun 130061China College of Mining Liaoning Technical UniversityFuxin 123000China Qiqihaer Institute of Geological Exploration Heilongjiang 161006China School of Environment Harbin Institute of TechnologyHarbin 150090China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Land and ResourcesChangchun 130061China

Multi-stage igneous rocks developed in the recently discovered Huoluotai Cu-(Mo)deposit provide new insights into the controversial late Mesozoic geodynamic evolution of the northern segment of the Great Xing’an Range(NSGXR).Zircon U-Pb dating suggests that the monzogranite,ore-bearing granodiorite porphyry,diorite porphyry,and granite porphyry in the deposit were emplaced at 179.5±1.6,148.9±0.9,146.1±1.3,and 142.2±1.5 Ma,respectively.The Re-Os dating of molybdenite yielded an isochron age of 146.9±2.3 Ma(MSWD=0.27).The Jurassic adakitic monzogranite and granodiorite porphyry are characterized by high SiO_(2)and Na_(2)O contents,low K_(2)O/Na_(2)O ratios,low Mg O,Cr,and Ni contents,low zirconεHf(t)values relative to depleted mantle,and relatively high Th contents.They were produced by partial melting of a subducted oceanic slab,with involvement of marine sediments in the magma source and limited interaction with mantle peridotites during magma ascent.The Late Jurassic diorite porphyry is characterized by moderate SiO_(2) contents,high Mg O,Cr,and Ni contents,and positive dominatedεHf(t)values,indicating it was produced by partial melting of a subduction-modified lithospheric mantle wedge and underwent limited crustal contamination during magma ascent.The early Early Cretaceous adakitic granite porphyry shows high SiO_(2) and K_(2)O contents and K_(2)O/Na_(2)O ratios,low Mg O,Cr,and Ni contents,enriched Sr-Nd isotopic compositions,and slightly positive zirconεHf(t)values,suggesting it was produced by partial melting of thickened mafic lower crust.The NSGXR experienced a tectonic history that involved flat-slab subduction(200-160 Ma),and tearing and collapse(150-145 Ma)of the Mongol-Okhotsk oceanic lithosphere.The period of magmatic quiescence from ca.160 to 150 Ma was a response to flat-slab subduction of the Mongol-Okhotsk oceanic lithosphere.Crustal thickening in the NSGXR(145-133 Ma)was due to the collision between the Amuria Block and the Siberian Craton.

关键词： Geochemistry Zircon U-Pb dating Huoluotai Cu-(Mo)deposit Flat-slab subduction Mongol-Okhotsk Ocean

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共通与共谋:论语派杂志的生成逻辑

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临沂大学学报 2024年第2期46卷 10-21页

作者：李茜烨中山大学中文系(珠海) 广东珠海519000

论语派杂志的共通性是在自我定位和他者刺激之下才得以完整形成的,也是一次文学、政治与都市文化中商业出版的共谋。在《论语》《人间世》和《宇宙风》中,论语派反复对小品文进行言说,又因为左翼文学团体与官方的在场,论语派杂志才从一... 详细信息

论语派杂志的共通性是在自我定位和他者刺激之下才得以完整形成的,也是一次文学、政治与都市文化中商业出版的共谋。在《论语》《人间世》和《宇宙风》中,论语派反复对小品文进行言说,又因为左翼文学团体与官方的在场,论语派杂志才从一个以自说自话为目的和有着经济考量的刊物,转变成了以性灵幽默文学观为根基并指向功利主义文学工具论的阵地。得益于20世纪30年代上海商业出版的繁荣,论语派杂志利用一系列的编辑、发行策略形成庞大的认同群体,维持其共通体的运行。独立的经济能力使论语派杂志得以自主运营,然而,消费文化也使其产生了媚俗倾向。

关键词：论语派林语堂商业出版《论语》《人间世》《宇宙风》

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天线近场球面扫描面形测量技术及相关问题研究

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中国科学：物理学、力学、天文学 2024年第1期54卷 50-64页

作者：叶骞王博阳杨德金孟国香王娜上海交通大学机械与动力工程学院上海200240 中国科学院上海天文台上海200030 中国科学院新疆天文台乌鲁木齐830011 重庆交通大学土木工程学院重庆400074

本文提出了一种通过扫描天线近场半球表面电场强度来获取天线面形分布的新方法,该方法无需测量相位、扫描面积小、可实现全姿态测量.研究将微分几何理论与几何光学方法相结合,推导出了球面近场幅值分布与表面变形间直接映射关系的解析形... 详细信息

本文提出了一种通过扫描天线近场半球表面电场强度来获取天线面形分布的新方法,该方法无需测量相位、扫描面积小、可实现全姿态测量.研究将微分几何理论与几何光学方法相结合,推导出了球面近场幅值分布与表面变形间直接映射关系的解析形式-幅值变形方程,并基于有限差分法和傅里叶变换法对方程进行求解,使用几何光学数值仿真证明了幅值变形方程的准确性和测量方法的有效性.结合本文提出的扫描机构设计从扫描分辨率限制、探头定位误差和测量信噪比等角度分析验证了测量方案的可行性,并重点使用基于物理光学和物理绕射理论的数值仿真模拟了整体测量精度.此外引入奇异值分解去噪方法降低了低信噪比对测量精度的影响.

关键词：射电望远镜天线几何光学数学过程

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