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Experimental study of a single-cylinder engine fuelled with natural gas-hydrogen mixtures

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Experimental study of a single-cylinder engine fuelled with ...

ANALYSIS ON SHEAR STRENGTH-FABRIC RELATIONSHIP FOR UNSATURATED GRANULAR SOILS

第九届全国氢能学术会议

作者： J.Xu,X.Zhang,J.H.Liu beijing jiao tong university,China

＜正＞The objective of this study is to evaluate the power,efficiency and emissions of an electronic-controlled single-cylinder engine fuelled with pure natural gas and natural gas-hydrogen blends,*** using the orthogonal tests method,a range of engine conditions were *** results show that under certain engine conditions the

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ANALYSIS ON SHEAR STRENGTH-FABRIC RELATIONSHIP FOR UNSATURAT...

A Linear Motor Position Control Based on the Artificial Immune Clustering Methodology

岩石力学与工程的创新和实践：第十一次全国岩石力学与工程学术大会

作者： Zhang Wei-hua,Zhao Cheng-gang~1 (School of Civil Engineering,beijing jiao-tong university,beijing 100044 P.R.China)

Based on micromechanics,this paper establishes the relationship between shear strength and fabric for unsaturated pendular-state granular soils,and some conclusions can be made:The two internal frictional anglesφandφ at critical state are all strength parameters related to the frictional characteristic of the interparticle contacts,which is intrinsic properties of the soil,the former is the sum of three contributions representing anisotropics in contact orientations,average normal and tangential forces,and the latter is directly related to the contact normals and independent of capillary ***,DEM numerical simulations of triaxial compression tests at different degrees of saturation in pendular state are used to verify the conclusion.

关键词： unsaturated granular soils pendular state fabric shear strength internal friction angle anisotropy

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A Linear Motor Position Control Based on the Artificial Immu...

流变挤压铸造7075铝合金的组织及力学性能

第二十六届中国控制会议

作者： Liu Yang 1,Liu Ying 2 1.Shandong university of Technology Zibo City,Shandong Province 255049,P.R.China 2.beijing jiao tong university,beijing 100044,P.R.China

In this paper,a novel algorithm,the artificial immune clustering methodology（AICM）,is developed to control the position of the permanent magnet linear synchronous motor（PMLSM）*** advantage of the AICM,perfect learning and adaptability,as well as efficient pattern recognition,enhances the data process ability of PMLSM,which results in the improved position-precision and *** experimental results are given out and the validity of this method is verified.

关键词： PMLSM immune system the artificial immune clustering method

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特种铸造及有色合金 2008年第S1期28卷 419-423页

作者：李楠邢书明鲍培玮郭文龙北京交通大学机电工程学院半固态成型研究中心

以7075铝合金为例,对变形铝合金流变成型的组织和力学性能进行了研究,探讨了采用流变成型方法生产高性能变形铝合金的可行性。试验证明,通过斜坡冷却法直接获得半固态浆料,结合特殊的挤压铸造工艺,获得了组织致密,无微观气孔、微观缩孔... 详细信息

以7075铝合金为例,对变形铝合金流变成型的组织和力学性能进行了研究,探讨了采用流变成型方法生产高性能变形铝合金的可行性。试验证明,通过斜坡冷却法直接获得半固态浆料,结合特殊的挤压铸造工艺,获得了组织致密,无微观气孔、微观缩孔的优良工件。通过3个成形比压水平(80MPa,87MPa,95MPa)和3种热处理制度下7075铝合金的组织性能对比,发现流变成形工件的性能远优于同等材质的金属型普通铸造工件,最高抗拉强度达到502MPa,接近于锻件水平,随着比压增大,工件的致密度随之提高,但强度提高不明显。不同热处理对于流变成形7075变形铝合金的抗拉强度影响不明显,但时效作用对于伸长率影响很大。

关键词：流变成形挤压铸造7075变形铝合金挤压铸造力学性能

多孔硅对多晶硅太阳电池中缺陷和杂质的吸除效应

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太阳能学报 2004年第2期25卷 259-262页

作者：朱琳徐征许颖李海玲王文静北京交通大学光电子技术研究所北京北京市太阳能研究所

吸杂是减少硅中杂质和缺陷,提高多晶硅太阳电池效率的一种有效手段。本文比较了用三种吸杂方式对多晶硅进行处理的结果和影响:多孔硅吸杂,磷吸杂,多孔硅结合磷吸杂。三种吸杂方式都能明显提高多晶硅的少子寿命。在此基础上研究了多孔硅... 详细信息

吸杂是减少硅中杂质和缺陷,提高多晶硅太阳电池效率的一种有效手段。本文比较了用三种吸杂方式对多晶硅进行处理的结果和影响:多孔硅吸杂,磷吸杂,多孔硅结合磷吸杂。三种吸杂方式都能明显提高多晶硅的少子寿命。在此基础上研究了多孔硅吸杂的工艺,发现多孔硅吸杂的效果随退火的温度和时间影响比较大,在800℃氮气气氛下退火3h,多晶硅的少子寿命能由原来的1 4μs提高到25 6μs。相比之下,多孔硅吸杂工艺简单,更适合工业生产。

关键词：少子寿命多孔硅吸杂

Control upconversion decay dynamics from perspective of collective response

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Journal of Rare Earths 2025年第1期43卷 57-63,I0003页

作者： Yingdong Han Yutong Pan tong Wei Yu Ma Xingxing Zhang Lei Jiang Kai Chen Liwei Wu jiao Cui Chao Gao College of Science Civil Aviation University of ChinaTianjin300300China School of Inspection and Testing Certification Changzhou Vocational Institute of EngineeringChangzhou213164China School of Chemical and Physical Sciences Victoria University of WellingtonWellington6012New Zealand Robinson Research Institute Faculty of EngineeringVictoria University of WellingtonWellington6012New Zealand

Very recently,upconversion luminescence(UCL)lifetime,as a powerful optical dimension,has attracted tremendous research interest due to its advantages of high information capacity and high photophysical *** the implementation and emergence of endlessly fascinating UCL features,it is particularly meaningful to understand the photophysical mechanisms inside UCL materials to enable rational subdivision-level structure design,which is however currently far from *** this work,we take an ordinary upconversion nanoparticle as an example to prove that the UCL decay curves and corresponding lifetimes are indeed a collective response of the entire UCL system to excitations,that exhibits correlated,yet quite different properties from individual ions.A specially developed theoretical random walk model combined with an experimental lifetime control for Yb^(3+)/Er^(3+)UCL demonstrates that ene rgy diffusion principally alters the decay ***,the different extent of the influence of energy diffusion on the emissions of ^(2)H_(11/2)/^(4)S_(3/2)(green)and ^(4)F_(9/2)(red)leads to an extremely uncommon crossover comparison of decay *** work provides new ideas for understanding decay dynamics and practical UCL lifetime manipulation methods.

关键词： Upconversion Lifetime Collective response Decaycurves Random walk model Rare earths

Advances in the Development of Gradient Scaffolds Made of Nano‑Micromaterials for Musculoskeletal Tissue Regeneration

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Nano-Micro Letters 2025年第3期17卷 455-500页

作者： Lei Fang Xiaoqi Lin Ruian Xu Lu Liu Yu Zhang Feng Tian jiao jiao Li Jiajia Xue beijing Laboratory of Biomedical Materials Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China School of Biomedical Engineering Faculty of Engineering and ITUniversity of Technology SydneySydneyNSW 2007Australia

The intricate hierarchical structure of musculoskeletal tissues,including bone and interface tissues,necessitates the use of complex scaffold designs and material structures to serve as tissue-engineered *** has led to growing interest in the development of gradient bone scaffolds with hierarchical structures mimicking the extracellular matrix of native tissues to achieve improved therapeutic *** on the anatomical characteristics of bone and interfacial tissues,this review provides a summary of current strategies used to design and fabricate biomimetic gradient scaffolds for repairing musculoskeletal tissues,specifically focusing on methods used to construct compositional and structural gradients within the *** latest applications of gradient scaffolds for the regeneration of bone,osteochondral,and tendon-to-bone interfaces are ***,the current progress of testing gradient scaffolds in physiologically relevant animal models of skeletal repair is discussed,as well as the challenges and prospects of moving these scaffolds into clinical application for treating musculoskeletal injuries.

关键词： Gradient scaffolds Musculoskeletal tissues Advanced manufacturing Biomaterials Tissue regeneration

Marine dispersion of Fukushima-derived radiocesium in the North Pacific and its implications

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Science China Earth Sciences 2025年第2期68卷 389-406页

作者： tong ZHANG Xiaolin HOU Yukun FAN State Key Laboratory of Loess and Quaternary Geology Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and ApplicationXi’an AMS CenterInstitute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China university of Chinese Academy of Sciences Beijing 100049China Xi’an Institute for Innovative Earth Environment Research Xi’an 710061China

A key scientific approach to addressing the environmental radiation risks from Fukushima nuclear contaminated water(FNCW) discharge into the ocean is understanding and predicting the marine dispersion of *** dispersion of radiocesium(CsF:134Cs,137Cs) from the Fukushima nuclear accident in the North Pacific and its marginal seas post-2011 was systematically summarized,focusing on pathways,vertical distribution changes,and transit *** research examined CsFdispersion through the Kuroshio Extension and denser central mode water(D-CMW) to the eastern North Pacific,as well as through subtropical mode water(STMW),lighter central mode water(L-CMW),and D-CMW to the subtropical western North Pacific,China Seas,and Sea of *** considered broader implications of CsFdispersion in light of ongoing FNCW *** this prolonged liquid discharge and Kuroshio Extension’s barrier effect,it is crucial to emphasize the role of CMW besides STMW in transporting FNCW to the subtropical western North Pacific and its marginal *** research should focus on the key mechanism and longitude range of CMW crossing the Kuroshio *** short-lived134Cs decays rapidly during the storage and dispersion of FNCW,long-lived135Cs and135Cs/137Cs ratios can serve as valuable tracers for detecting and quantifying ***,there is an urgent need for high-precision analysis of these key radionuclides and their characteristic *** promptly detect,assess,and respond to FNCW intrusion,continuous monitoring and identification of nuclear pollution sources in key ocean currents and straits are ***,interdisciplinary research integrating monitoring with marginal sea circulation dynamics and high-resolution numerical simulations should be a priority.

关键词： Fukushima nuclear accident Fukushima nuclear contaminated water Marine dispersion Mode water Kuroshio Extension

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A water probe for direct pH measurement of individual particles via micro-Raman spectroscopy

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Journal of Environmental Sciences 2025年第3期149卷 200-208页

作者： Xiaoyu Cui Mingjin Tang tong Zhu School of Environmental Science and Engineering Tianjin UniversityTianjin 300072China BIC-ESAT and SKL-ESPC College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

The acidity of atmospheric aerosols influences fundamental physicochemical processes that affect climate and human *** recently developed a novel and facilewater-probebased method for directly measuring of the pH for micrometer-size droplets,providing a promising technique to better understand aerosol acidity in the *** complex chemical composition of fine particles in the ambient air,however,poses certain challenges to using a water-probe for pH measurement,including interference from interactions between compositions and the influence of similar compositions on water *** explore the universality of our method,it was employed to measure the pH of ammonium,nitrate,carbonate,sulfate,and chloride *** pH of particles covering a broad range(0–14)were accurately determined,thereby demonstrating that our method can be generally applied,even to alkaline ***,a standard spectral library was developed by integrating the standard spectra of common hydrated ions extracted through the *** library can be employed to identify particle composition and overcome the spectral overlap problem resulting from similar *** the spectral library,all ions were identified and their concentrations were determined,in turn allowing successful pH measurement of multicomponent(ammonium-sulfate-nitrate-chloride)*** into the synergistic effect of Cl^(–),NO_(3)^(–),and NH_(4)^(+)depletion obtained with our approach revealed the interplay between pH and volatile *** the ubiquity of component partitioning and pH variation in particles,the water probemay provide a new perspective on the underlying mechanisms of aerosol aging and aerosol–cloud interaction.

关键词： Particle pH Water probe Standard spectral library Micro-Raman spectroscopy Direct measurement