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On the "good understanding" of the Scientific Spirit: The Use of Metaphors and Images in the Physical Sciences
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《Journal of Philosophy Study》 2011年第5期327-333,共7页
In Bachelard's thought, the understanding "of the other" in scientific thought is given usually by means of empirical or rational discourse. However, it is not unusual to realize the emphasis of scientific thought ... In Bachelard's thought, the understanding "of the other" in scientific thought is given usually by means of empirical or rational discourse. However, it is not unusual to realize the emphasis of scientific thought as rationally justifiable. Certainly, the dynamics of scientific thought throughout history has not been indifferent to other possibilities of epistemological construction. We cannot escape the facts: Science needs linguistic devices to strengthen its principles and criteria for validation. The aim of this paper is to answer, based on a new conception of metaphor, under what conditions metaphor can be a "physical metaphor" and the extent to which the symbolism in general brings a special light gain of sense to the understanding of physical reality that surrounds us. 展开更多
关键词 BACHELARD BENJAMIN physics raetaphor image
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Ground-based and additional science support for SMILE 被引量:2
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作者 J.A.Carter M.Dunlop +46 位作者 C.Forsyth K.Oksavik E.Donovon A.Kavanagh S.E.Milan T.Sergienko R.C.Fear D.G.Sibeck M.Connors T.Yeoman X.Tan M.G.G.T.Taylor K.McWilliams J.Gjerloev R.Barnes D.D.Billet G.Chisham A.Dimmock M.P.Freeman D.-S.Han M.D.Hartinger S.-Y.W.Hsieh Z.-J.Hu M.K.James L.Juusola K.Kauristie E.A.Kronberg M.Lester J.Manuel J.Matzka I.McCrea Y.Miyoshi J.Rae L.Ren F.Sigernes E.Spanswick K.Sterne A.Steuwer T.Sun M.-T.Walach B.Walsh C.Wang J.Weygand J.Wild J.Yan J.Zhang Q.-H.Zhang 《Earth and Planetary Physics》 EI CSCD 2024年第1期275-298,共24页
The joint European Space Agency and Chinese Academy of Sciences Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will explore global dynamics of the magnetosphere under varying solar wind and interplane... The joint European Space Agency and Chinese Academy of Sciences Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will explore global dynamics of the magnetosphere under varying solar wind and interplanetary magnetic field conditions,and simultaneously monitor the auroral response of the Northern Hemisphere ionosphere.Combining these large-scale responses with medium and fine-scale measurements at a variety of cadences by additional ground-based and space-based instruments will enable a much greater scientific impact beyond the original goals of the SMILE mission.Here,we describe current community efforts to prepare for SMILE,and the benefits and context various experiments that have explicitly expressed support for SMILE can offer.A dedicated group of international scientists representing many different experiment types and geographical locations,the Ground-based and Additional Science Working Group,is facilitating these efforts.Preparations include constructing an online SMILE Data Fusion Facility,the discussion of particular or special modes for experiments such as coherent and incoherent scatter radar,and the consideration of particular observing strategies and spacecraft conjunctions.We anticipate growing interest and community engagement with the SMILE mission,and we welcome novel ideas and insights from the solar-terrestrial community. 展开更多
关键词 MAGNETOSPHERE IONOSPHERE magnetosphere-ionosphere coupling ground-based experimentation SMILE CONJUNCTIONS MISSIONS
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Effects of extended anionic surfactants on the wettability of polytetrafluoroethylene interface
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作者 Qi Sun Zhengrong Zhao +2 位作者 Zhicheng Xu Lei Zhang Lu Zhang 《日用化学工业(中英文)》 北大核心 2025年第8期949-960,共12页
In order to explore the mechanism of improving the surface wettability of low-energy polytetrafluoroethylene(PTFE)by new extended surfactants,five kinds of extended anionic surfactants with different numbers of oxypro... In order to explore the mechanism of improving the surface wettability of low-energy polytetrafluoroethylene(PTFE)by new extended surfactants,five kinds of extended anionic surfactants with different numbers of oxypropylene(PO)and oxyethylene(EO),octadecyl-(PO)_(m)-(EO)_(n)-sodium carboxylate(C_(18)PO_(m)EO_(n)C,m=5,10,15,n=5,10,15),were studied.The surface tension and contact angle of C_(18)PO_(m)EO_(n)C solution with different concentrations were measured,and the adhesion tension,PTFE-water interfacial tension,and adhesion work were calculated.It was found that the extended surfactant molecules adsorb on the surface of the solution and the PTFE-liquid interface simultaneously when the concentration is lower than the critical micelle concentration(cmc),and there was a linear relationship between surface tension and adhesion tension.The adsorption amount of C_(18)PO_(m)EO_(n)C at the PTFE-water interface was significantly lower than that on the surface of the solution.As the concentration increases above cmc,semi-micelle aggregates on the surface of PTFE are formed by C_(18)PO_(m)EO_(n)C molecules through hydrophobic interaction,and the hydrophilic group faces the solution to modify the surface of PTFE with high efficiency. 展开更多
关键词 WETTABILITY contact angle extended surfactant polypropylene oxide polyethylene oxide
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Study on the causes of weathering steel corrosion for railway freight cars with a load capacity of 70 tons
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作者 Wei Du Yi Wu +2 位作者 Zhongyu Yi Ruohan Xiang Yishuo Liu 《Railway Sciences》 2025年第3期356-374,共19页
Purpose-Weathering steel has excellent resistance to atmospheric corrosion,but still faces complex environmental corrosion problems during long-term operation.This paper mainly studies the corrosion problem of weather... Purpose-Weathering steel has excellent resistance to atmospheric corrosion,but still faces complex environmental corrosion problems during long-term operation.This paper mainly studies the corrosion problem of weather resistant steel materials for railway freight car bodies with a load capacity of 70 tons.Design/methodology/approach-The paper analyzes the corrosion characteristics of weather resistant steel materials for truck bodies through macroscopic and microscopic methods including metallographic microscopy,scanning electron microscopy,energy dispersive spectroscopy and X-ray diffraction.Electrochemical analysis shows that the rust layer on the surface of weathering steel changes the surface state of the material,and also proves that weathering steel used in trucks undergoes electrochemical corrosion under atmospheric corrosion.At the same time,ion chromatography technology is used to study the corrosive ions mainly present in the residual liquid and foam solution inside the vehicle body.Findings-The corrosion of truck body materials is mainly electrochemical corrosion,and the corrosion of door materials is more obvious than that of other parts.The corrosion products are mainly Fe oxides and hydroxides.There are high concentrations of Cl-and SO42-ions in the residual liquid and foam solution at the bottom of the freight car,which are the main factors causing corrosion of the railway freight car body.Originality/value-The foam adhesive around the door panel is in a moist state for a long time,and corrosive ions will accelerate the electrochemical corrosion of the weather resistant steel material of the door panel.Therefore,the corrosion of the cargo door panel is more severe than other components. 展开更多
关键词 Railway freight cars CORROSION Residual liquid Electrochemical corrosion
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Facet-Dependent Performance of Microstructured SrTiO_(3) Particles in Photocatalytic Oxidation of Acetone
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作者 Nathália Tavares Costa Daniel Monteiro Cunha +5 位作者 Kaijian Zhu Annemarie Huijser Georgios Katsoukis Kasper Wenderich Jitte Flapper Guido Mul 《Energy & Environmental Materials》 2025年第3期161-171,共11页
Photocatalysis is a promising technology for purification of indoor air by oxidation of volatile organic compounds.This study provides a comprehensive analysis of the adsorption and photo-oxidation of surface-adsorbed... Photocatalysis is a promising technology for purification of indoor air by oxidation of volatile organic compounds.This study provides a comprehensive analysis of the adsorption and photo-oxidation of surface-adsorbed acetone on three SrTiO_(3)morphologies:cubes(for which exclusively{100}facets are exposed),{110}-truncated cubes,and{100}-truncated rhombic dodecahedrons,respectively,all prepared by hydrothermal synthesis.In situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy shows that cubic crystals contain a high quantity of surface-OH groups,enabling significant quantities of adsorbed acetone in the form ofη^(1)-enolate when exposed to gas phase acetone.Contrary,{110}facets exhibit fewer surface-OH groups,resulting in relatively small quantities of adsorbedη^(1)-acetone,without observable quantities of enolate.Interestingly,acetate and formate signatures appear in the spectra of cubic,surfaceη^(1)-enolate containing,SrTiO_(3)upon illumination,while besides acetate and formate,the formation of(surface)formaldehyde was observed on truncated cubes,and dodecahedrons,by conversion of adsorbedη^(1)-acetone.Time-Resolved Photoluminescence studies demonstrate that the lifetimes of photogenerated charge carriers vary with crystal morphology.The shortest carrier lifetime(τ_(1)=33±0.1 ps)was observed in{110}-truncated cube SrTiO_(3),likely due to a relatively strong built-in electric field promoting electron transport to{100}facets and hole transport to{110}facets.The second lifetime(τ_(2)=259±1 ps)was also the shortest for this morphology,possibly due to a higher amount of surface trap states.Our results demonstrate that SrTiO_(3)crystal morphology can be tuned to optimize performance in photocatalytic oxidation. 展开更多
关键词 faceted SrTiO_(3) in situ DRIFTS PHOTOCATALYSIS TRPL VOC oxidation
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Predictive analysis of dry eye diagnosis and digital screen usage: a cross-sectional study
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作者 Rekha Ghimire Raju Kaiti +2 位作者 Ranjila Shyangbo Santosh Paudel Youbraj Neupane 《International Journal of Ophthalmology(English edition)》 2025年第10期1851-1855,共5页
AIM:To characterize the ocular surface characteristics in the Nepalese population across all age groups who have used digital screens for extended durations over several years.METHODS:In a cross-sectional,observationa... AIM:To characterize the ocular surface characteristics in the Nepalese population across all age groups who have used digital screens for extended durations over several years.METHODS:In a cross-sectional,observational study,144 digital screen users were assessed for dry eye disease(DED)using subjective and objective measures.The Ocular Surface Disease Index(OSDI)Questionnaire evaluated symptoms,followed by clinical assessments,including slit lamp biomicroscopy,tear breakup time(TBUT),Oxford Scheme grading,and Schirmer I test.DED was diagnosed if a patient had an OSDI score over 13 and at least two clinical signs(OSDI,Schirmer I test,or ocular staining).The prevalence of DED was calculated based on the proportion of patients meeting these criteria.RESULTS:Of the 144 participants(mean age:34.6±15.2y),78(54.2%)were female.The use of digital screens varied between 2-8h(mean duration:4.1±2.7h)per day.The mean OSDI score,TBUT score,and the Schirmer I scores were 22.7±10.5(max-min:24.4-20.9),6.8±4.2s(max-min:7.5-6.1),and 12.3±4.6 mm(max-min:13.1-11.5)respectively with 95%confidence interval(β=1.96),and a two-tailed statistical significance level of 5%(α=0.05).With increased screen use,TBUT shortened and OSDI scores increased significantly(P<0.01),though Schirmer I scores were unaffected(P>0.05).The prevalence of DED ranged from 6.3%to 22.9%in those using screens for more than 2h,with an overall prevalence of 67.4%among digital screen users.CONCLUSION:There is a significant association between prolonged use of digital screens and clinical markers of dry eye signs and symptoms. 展开更多
关键词 digital devices digital eye strain screen time BLINKING tear film stability
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Designation of the Lectotype for Tropidophorus laotus(Reptilia:Scincidae)and Description of A New Closely Related Species from Southern Yunnan Province, China
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作者 Kai WANG Ling LI +8 位作者 VDEEPAK Somphouthone PHIMMACHAK Stéphane GROSJEAN Nicolas VIDAL Zhongxiong FU Fenfei WANG Guojin SHEN Bryan LSTUART Jing CHE 《Asian Herpetological Research》 2025年第1期95-109,共15页
Despite continuous progress made on the taxonomy of the genus Tropidophorus, the Lao Water Skink, T. laotus, is only known from brief descriptions of its syntypes in historical literature. Here we designate a lectotyp... Despite continuous progress made on the taxonomy of the genus Tropidophorus, the Lao Water Skink, T. laotus, is only known from brief descriptions of its syntypes in historical literature. Here we designate a lectotype and paralectotype of the species, redescribe the species based on the type series and newly collected topotypes, provide the first colored photographs of taxonomically-verified individuals, and estimate its phylogenetic position using mitochondrial DNA data for the first time.Using these comparable data, we confirm that the previously identified “T. berdmorei” population from southern Yunnan Province, China, represents a distinct new species that is closely related and morphologically similar to T. laotus, but differs from true T. laotus by having considerable genetic divergence(4.7%–4.8% for 12S, 3.2%–4.2% for 16S)and distinct morphological characters(e.g., undivided frontonasal scales and a distinct color pattern of the throat). The southern Yunnan population is therefore described as a new species. With the above newly acquired data, we update the checklist and the provincial-level distribution of the genus Tropidophorus in China and compile an updated key to all recognized species of the genus from China and Indochina. 展开更多
关键词 cross-border distribution MISIDENTIFICATION SCINCIDAE taxonomy
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Round-the-Clock Photocatalysts in the Post-Irradiation Dark Period:From Light Charging to“Memory”Dark Discharging Toward Hydrogen Production
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作者 Balvinder Kaur Pardeep Singh +5 位作者 Duc Anh Dinh Xuan-Cuong Luu Krishna Kumar Yadav Maha Awjan Alreshidi Van-Huy Nguyen Pankaj Raizada 《Transactions of Tianjin University》 2025年第6期645-668,共24页
The intermittent nature of solar irradiance is a critical constraint for the realization of continuous photocatalytic hydrogen evolution,thus urging the development of more powerful systems persistently active after i... The intermittent nature of solar irradiance is a critical constraint for the realization of continuous photocatalytic hydrogen evolution,thus urging the development of more powerful systems persistently active after illumination.This limitation is bypassed in round-the-clock photocatalytic architectures,which incorporate advanced charge storage to de-correlate pho-ton absorption and catalytic turnover time scales.The strategies involve defect-mediated trap states,multi-electron redox processes,radical-dependent stabilization,and an interfacial charge pool in Faradaic junctions to work together,leading to extended hydrogen evolution reaction(HER)in the dark.Long afterglow phosphorescent materials(e.g.,Sr_(2)MgSi_(2)O_(7):Eu^(2+),Dy^(3+))incorporated in heterojunction architectures with type II or Z-scheme band alignments can also promote fast charge separation for energy storage and subsequently enable controlled release after light quenching by the phosphorescent emis-sion.Advances in band-structure engineering,plasmonic coupling,and redox-active interfacial design result in systems with extraordinary stability and catalytic activity under natural day-night cycles.These stable photocatalytic systems off er a fundamentally new strategy for effi cient and environmentally benign sunlight-driven fuel production,meeting both per-formance and sustainability challenges to renewable energy technologies. 展开更多
关键词 Round-the-clock photocatalysis Dark hydrogen evolution Charge storage Memory effect Persistent luminescence materials
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45S rDNA在4种百合属植物染色体上的物理定位 被引量:14
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作者 周树军 Jaap van Tuyl +2 位作者 臧德奎 夏宜平 李方 《园艺学报》 CAS CSCD 北大核心 2008年第6期859-862,共4页
利用荧光原位杂交的技术将45SrDNA在麝香百合(Lilium longiflorum),柠檬色百合(L.leichtlinii),天香百合(L.auratum)和豹纹百合(L.pardalinum)的染色体上进行了定位。结果表明:45S rDNA在这4种植物中都分布于染色体的着丝点附近,但其位... 利用荧光原位杂交的技术将45SrDNA在麝香百合(Lilium longiflorum),柠檬色百合(L.leichtlinii),天香百合(L.auratum)和豹纹百合(L.pardalinum)的染色体上进行了定位。结果表明:45S rDNA在这4种植物中都分布于染色体的着丝点附近,但其位点数量、所在的染色体和信号的强弱有很大的变化。其中,麝香百合和豹纹百合中各有3对染色体在着丝点附近有45S rDNA的信号,柠檬色百合和天香百合中各有4对染色体在着丝点附近有45S rDNA的信号。但是天香百合的两对中部染色体的着丝点附近都有45S rDNA的信号,柠檬色百合的两对中部染色体中只有一条有45S rDNA的信号,而麝香百合和豹纹百合中没有任何一条有45S rDNA的信号。由于这4种百合在百合属中分别属于不同组,其45S rDNA的位点数量、所在染色体和信号强弱的变化为这种分组的合理性提供了一些分子生物学的证据。 展开更多
关键词 百合 RDNA 荧光原位杂交(FISH) 核型 染色体
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公众科学在欧美生态环境研究和管理中的应用 被引量:14
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作者 李春明 张会 HAKLAY Muki 《生态学报》 CAS CSCD 北大核心 2018年第6期2239-2245,共7页
近十年来以大量公众参与科学研究活动为特征的公众科学在生态环境研究和管理中得到了快速发展,根据公众和科学家之间的合作程度不同出现了以贡献型、协作型和共创型为主的应用模式,并在生物多样性调查、环境质量监测、生态环境管理中表... 近十年来以大量公众参与科学研究活动为特征的公众科学在生态环境研究和管理中得到了快速发展,根据公众和科学家之间的合作程度不同出现了以贡献型、协作型和共创型为主的应用模式,并在生物多样性调查、环境质量监测、生态环境管理中表现出了极大的潜在价值。通过对欧美公众科学在生态环境研究和管理中的典型案例进行介绍,分析了其概念内涵,概括了其项目的组成结构和应用模式,指出了面临的挑战和发展趋势。结论如下:(1)传感器技术的进步、便携式智能设备和移动网络普及使得公众获取周边生态环境信息的能力日益增强,种类也日益多样。(2)公众科学项目的运用不仅能够扩大数据获取范围,也能加深公众对科学问题的认识和提高管理部门科学决策水平。(3)公众提供的数据种类,数据质量,以及公众激励机制,都是该模式持续和高质量运行时所要面临的挑战。(4)欧美一些"科研单位-公众机构-公民团体"等纷纷联合起来形成公众科学协会,同时政府部门已制定了公众科学发展计划和法规,来规范和促进公众科学项目的应用。(5)我国相关研究和管理部门应建立统一协作平台,进一步引导公众科学参与和提高协作效率。 展开更多
关键词 公众科学 应用模式 公众参与 生态 环境
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磷酸掺杂的聚苯并咪唑复合膜在高温质子交换膜燃料电池中的应用(英文) 被引量:2
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作者 何荣桓 李庆峰 Bjerrum Niels J 《应用化学》 CAS CSCD 北大核心 2006年第7期697-703,共7页
研制了聚苯并咪唑(PB I)的复合膜,复合膜中引入的组分包括无机质子导体磷酸氢锆(Zr(HPO4)2.nH2O,ZrP)和聚砜(PSF),以及磺化的酸型聚砜(SPSF(H))。热失重分析表明,复合膜PB I/ZrP/PSF和PB I/SPSF(H)的热稳定性可分别达400和230℃。磷酸... 研制了聚苯并咪唑(PB I)的复合膜,复合膜中引入的组分包括无机质子导体磷酸氢锆(Zr(HPO4)2.nH2O,ZrP)和聚砜(PSF),以及磺化的酸型聚砜(SPSF(H))。热失重分析表明,复合膜PB I/ZrP/PSF和PB I/SPSF(H)的热稳定性可分别达400和230℃。磷酸掺杂的PB I复合膜在温度高达200℃的低湿度条件下,呈现出高质子电导率。以磷酸掺杂的PB I复合膜为电解质,在200℃常压不加湿的条件下,以氢气氧气为燃料气进行了单电池测试,其最大功率密度分别为0.34 W/cm2(PB I/ZrP/PSF(质量比80∶15∶5))和0.38 W/cm2(PB I/SPSF(0.43H))。 展开更多
关键词 聚苯并咪唑 复合膜 电导率 质子交换膜 燃料电池
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秦安地区全新世气候的周期振荡特征 被引量:3
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作者 S. Feng 夏敦胜 +1 位作者 汤懋苍 陈发虎 《冰川冻土》 CSCD 北大核心 2006年第1期70-75,共6页
通过对秦安大地湾8.3 m天然黄土剖面高分辨率(约为150 a)孢粉数据的研究,发现秦安地区孢粉数据与我国干旱、半干旱地区史料记载的旱涝演变有较为一致的变化,且有明显的冷干、暖湿的气候特征.奇异谱分析表明,秦安地区的旱涝变化有2 300 a... 通过对秦安大地湾8.3 m天然黄土剖面高分辨率(约为150 a)孢粉数据的研究,发现秦安地区孢粉数据与我国干旱、半干旱地区史料记载的旱涝演变有较为一致的变化,且有明显的冷干、暖湿的气候特征.奇异谱分析表明,秦安地区的旱涝变化有2 300 a、1 060 a、650 a和390 a的准振荡周期.准两千年周期与南亚季风的变化有密切的对应关系,也与太阳活动的强弱有关. 展开更多
关键词 全新世 气候变化 奇异谱分析 秦安
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元强化学习研究综述 被引量:4
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作者 陈奕宇 霍静 +1 位作者 丁天雨 高阳 《软件学报》 EI CSCD 北大核心 2024年第4期1618-1650,共33页
近年来,深度强化学习(deep reinforcement learning,DRL)已经在诸多序贯决策任务中取得瞩目成功,但当前,深度强化学习的成功很大程度依赖于海量的学习数据与计算资源,低劣的样本效率和策略通用性是制约其进一步发展的关键因素.元强化学... 近年来,深度强化学习(deep reinforcement learning,DRL)已经在诸多序贯决策任务中取得瞩目成功,但当前,深度强化学习的成功很大程度依赖于海量的学习数据与计算资源,低劣的样本效率和策略通用性是制约其进一步发展的关键因素.元强化学习(meta-reinforcementlearning,Meta-RL)致力于以更小的样本量适应更广泛的任务,其研究有望缓解上述限制从而推进强化学习领域发展.以元强化学习工作的研究对象与适用场景为脉络,对元强化学习领域的研究进展进行了全面梳理:首先,对深度强化学习、元学习背景做基本介绍;然后,对元强化学习作形式化定义及常见的场景设置总结,并从元强化学习研究成果的适用范围角度展开介绍元强化学习的现有研究进展;最后,分析了元强化学习领域的研究挑战与发展前景. 展开更多
关键词 元强化学习 强化学习 深度强化学习 元学习
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FACE试验对土壤有机质库组分及其激发效应的影响 被引量:2
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作者 尚卫辉 舒薇 +2 位作者 李永涛 Marcel R.Hoosbeek Giuseppe E.Scarascia-Mugnozza 《生态环境》 CSCD 北大核心 2008年第4期1518-1522,共5页
以意大利的FACE(Free atmospheric CO2enrichment)长期定位试验区和大气环境控制装置为研究对象,用化学分步酸提法将土壤有机质分离为活性库、慢库和惰性库,并培养测定土壤有机氮的矿化率,研究人工模拟大气CO2富集、施氮肥及植株类型对... 以意大利的FACE(Free atmospheric CO2enrichment)长期定位试验区和大气环境控制装置为研究对象,用化学分步酸提法将土壤有机质分离为活性库、慢库和惰性库,并培养测定土壤有机氮的矿化率,研究人工模拟大气CO2富集、施氮肥及植株类型对土壤有机质库及激发效应的影响。第一茬(POP FACE)试验产生了激发效应,但第二茬(Euro FACE)试验CO2处理区的总碳增加量显著高于对照处理区,即激发效应终止。主成分分析显示,有效氮的矿化水平已成为有机质降解的制约因素。据此推断,试验区由活性碳和有效氮控制的激发效应阶段转变为氮利用受限所引起的碳积累阶段。CO2富集对N矿化率、慢库和惰性库均无显著性影响。研究结果表明,土壤的激发效应不仅受有机碳的活性库制约,氮的矿化率也是影响其发生的关键因子之一。 展开更多
关键词 有机质库 CO2富集 FACE 活性碳 酸提法
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Acute phase reaction and acute phase proteins 被引量:15
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作者 GRUYS E. TOUSSAINT M.J.M. +1 位作者 NIEWOLD T.A. KOOPMANS S.J. 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第11期1045-1056,共12页
A review of the systemic acute phase reaction with major cytokines involved, and the hepatic metabolic changes, negative and positive acute phase proteins (APPs) with function and associated pathology is given. It app... A review of the systemic acute phase reaction with major cytokines involved, and the hepatic metabolic changes, negative and positive acute phase proteins (APPs) with function and associated pathology is given. It appears that APPs represent appropriate analytes for assessment of animal health. Whereas they represent non-specific markers as biological effect reactants, they can be used for assessing nutritional deficits and reactive processes, especially when positive and negative acute phase variables are combined in an index. When such acute phase index is applied to separate healthy animals from animals with some disease, much better results are obtained than with single analytes and statistically acceptable results for culling individual animals may be reached. Unfortunately at present no cheap, comprehensive and easy to use system is available for assessing various acute phase proteins in serum or blood samples at the same time. Protein microarray or fluid phase microchip technology may satisfy this need; and permit simultaneous analysis of numerous analytes in the same small volume sample and enable integration of information derived from systemic reactivity and nutrition with disease specific variables. Applying such technology may help to solve health problems in various countries not only in animal husbandry but also in human populations. 展开更多
关键词 Acute phase protein Acute phase reaction Animal health ASSESSMENT CYTOKINE INDEX NUTRITION
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The effects of understory vegetation on P availability in Pinus radiata forest stands: A review 被引量:17
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作者 A.Arivin Rivaie 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第3期489-500,共12页
In many second-rotation Pinus radiata forest planta-tions, there has been a steady trend towards wider tree spacing and an increased rate of application of P fertiliser. Under these regimes, the potential for understo... In many second-rotation Pinus radiata forest planta-tions, there has been a steady trend towards wider tree spacing and an increased rate of application of P fertiliser. Under these regimes, the potential for understory growth is expected to in-crease through increased light and greater nutrient resources. Therefore, understory vegetation could become a more signifi-cant component of P cycling in P. radiata forests than under closely-spaced stands. Studies have shown that growth rates and survival of trees is reduced in the presence of understory vegeta-tion due to the competition of understory vegetation with trees. Other studies have suggested that understory vegetation might have beneficial effects on nutrient cycling and conservation within forest stands. This review discusses the significance of understory vegetation in radiata pine forest stands, especially their role in enhancing or reducing P availability to forest trees. 展开更多
关键词 understory vegetation significance phosphorus cycling Pinus radiata forests
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The role of calcium sensor-interacting protein kinases in plant adaptation to potassium-deficiency: new answers to old questions 被引量:11
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作者 Anna Amtmann Patrick Armengaud 《Cell Research》 SCIE CAS CSCD 2007年第6期483-485,共3页
Potassium (K^+) is an essential macronutrient for all living organisms and large amounts are required for plant growth and development. In many regions of Asia K+-fertilization has been neglected and soils have be... Potassium (K^+) is an essential macronutrient for all living organisms and large amounts are required for plant growth and development. In many regions of Asia K+-fertilization has been neglected and soils have become K+-depleted. K+- deficiency in the field diminishes not only crop production but also leads to environmental problems due to inefficient usage and leaching of nitrate. Consequences of K^+-deficiency on crop production range from decreased biomass, nutritional quality and taste of the crops to inferior harvest and storage properties, as well as increased susceptibility to disease. Effects of K^+-deficiency on plant physiology include decreased photosynthetic rate, impaired tissue allocation of sugars and amino acids, decreased protein synthesis. 展开更多
关键词 植物生物化学 钙传感相互作用蛋白激酶 钾缺乏 植物生长
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Transition Features from Simplicity-Universality to Complexity-Diversification Under UHNTF 被引量:5
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作者 方锦清 李勇 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第2期389-398,共10页
A large unified hybrid network model with a variable speed growth (LUHNM-VSG) is proposed as third model of the unified hybrid network theoretical framework (UHNTF). A hybrid growth ratio vg of deterministic linki... A large unified hybrid network model with a variable speed growth (LUHNM-VSG) is proposed as third model of the unified hybrid network theoretical framework (UHNTF). A hybrid growth ratio vg of deterministic linking number to random linking number and variable speed growth index a are introduced in it. The main effects of vg and a on topological transition features of the LUHNM-VSC are revealed. For comparison with the other models, we construct a type of the network complexity pyramid with seven levels, in which from the bottom level-1 to the top level-7 of the pyramid simplicity-universality is increasing but complexity-diversity is decreasing. The transition relations between them depend on matching of four hybrid ratios (dr, fd, gr, vg). Thus the most of network models can be investigated in the unification way via four hybrid ratios (dr, fd, gr, vg). The LUHNM-VSG as the level-1 of the pyramid is much better and closer to description of real-world networks as well as has potential application. 展开更多
关键词 unified hybrid network theoretical framework UNIFIED hybrid network model with variable speedgrowth network complexity pyramid complexity-diversification simplicity-universality
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Measuring consciousness in coma and related states 被引量:11
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作者 Carol Di Perri Aurore Thibaut +3 位作者 Lizette Heine Andrea Soddu Athena Demertzi Steven Laureys 《World Journal of Radiology》 CAS 2014年第8期589-597,共9页
Consciousness is a prismatic and ambiguous concept that still eludes any universal definition. Severe acquired brain injuries resulting in a disorder of con-sciousness(DOC) provide a model from which insights into con... Consciousness is a prismatic and ambiguous concept that still eludes any universal definition. Severe acquired brain injuries resulting in a disorder of con-sciousness(DOC) provide a model from which insights into consciousness can be drawn. A number of recent studies highlight the difficulty in making a diagnosis in patients with DOC based only on behavioral assessments. Here we aim to provide an overview of how neuroimaging techniques can help assess patients with DOC. Such techniques are expected to facilitate a more accurate understanding of brain function in states of unconsciousness and to improve the evaluation of thepatient's cognitive abilities by providing both diagnostic and prognostic indicators. 展开更多
关键词 Disorders of CONSCIOUSNESS Neuroimaging MAGNETIC resonance imaging Transcranial MAGNETIC stimulation/electroencephalography Minimally conscious STATE Vegetative state/unresponsive WAKEFULNESS syndrome
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Structural,phonon,elastic,thermodynamic and electronic properties of Mg-X(X=La,Nd,Sm)intermetallics:The first principles study 被引量:7
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作者 S.Rameshkumar G.Jaiganesh V.Jayalakshmi 《Journal of Magnesium and Alloys》 SCIE EI CAS 2019年第1期166-185,共20页
We show the results of first-principles calculations of structural,phonon,elastic,thermal and electronic properties of the Mg-X inter-metallics in their respective ground state phase and meta-stable phases at equilibr... We show the results of first-principles calculations of structural,phonon,elastic,thermal and electronic properties of the Mg-X inter-metallics in their respective ground state phase and meta-stable phases at equilibrium geometry and the studied pressure range.Phonon dispersion spectra for these compounds were investigated by using the linear response technique.The phonon spectra do not show any abnormality in their respective ground state phase.The respective ground states phases of the studied system remain stable within the studied pressure range.Electronic and thermodynamic properties were derived by analysis of the electronic structures and quasi-harmonic approximation.The mixed bonding character of the Mg-X intermetallics is revealed by Mg-X bonds,and it leads the metallic nature.Most of the contribution originated from X ions d like states at Fermi level compared to that of Mg ion in these intermetallics.In this work,we also predicted the melting temperature of these intermetallics and evaluated the Debye temperature by using elastic constants. 展开更多
关键词 Mg-X intermetallics First principle calculation Heat of formation Elastic constants Electronic and phonon properties Thermodynamic property
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