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International Conference on Aerospace Materials(ICAM 2006)

作者： Kenneth A. Green Randolph C. Helmink Rolls-Royce Corporation p.o. box 420 Indianapolis Indiana 46206 USA Rolls-Royce Corporation p.o. box 420 Indianapolis Indiana 46206 USA

This paper covers recent work in certain aspects of the design methodology, fabrication, and testing of dual grain structure disks. This type of structure enables the designer to optimize the design for creep resistance and damage tolerance in the rim and high strength in the bore, usually resulting in a lighter weight disk capable of higher temperatures. A trade study was conducted using several advanced, high temperature nickel disk alloys to determine which alloy would be most app.o.riate for a dual grain structure design. Alloy 10 was selected due to the availability of mechanical p.o.erties and favorable balance of p.o.erties, which showed a benefit for operating conditions in high temperature regimes. Two dual grain structure Alloy 10 disks were p.o.uced using a NASA patented p.o.ess called Dual Microstructure Heat Treat (DMHT). The transition zone placement was modeled using finite element code and verified in the disks using ultrasonic inspection. A third uniformly fine grain Alloy 10 disk was p.o.uced as a baseline for the spin testing. Mechanical p.o.erties were measured for fine and coarse grain material, as well as for the transition zone material. Cyclic testing across the transition zone confirmed the metallographic observations of a smooth transition from the fine grain to coarse grain structures and no metallurgical notches. The material data were input into linear and nonlinear finite element models to derive burst speed predictions for both the monolithic and dual structure disks using a conventional disk burst methodology and several advanced burst methodologies. overspeed testing was conducted at ambient temperature on two fully machined disks: one of dual grain structure material and the other of fine grain material. As expected, the fine grain Alloy 10 disk exhibited higher burst speed due to its higher strength at room temperature. All design models correctly predicted the burst initiation sites and the higher burst speed of the monolithic dis

关键词： Alloy 10, powder metallurgy, dual grain size, DMHT

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Systematic physicochemical characterization,carbon balance and cost of p.o.uction analyses of activated carbons derived from(Co)-HTC of coal discards and sewage sludge for hydrogen storage applications

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Waste Disposal and Sustainable Energy 2023年第2期5卷 125-149页

作者： Gentil Mwengula Kahilu Samson Bada Jean Mulopo DSI-NRF SARChI Clean Coal Technology research Group School of Chemical and Metallurgical EngineeringFaculty of Engineering and the Built EnvironmentUniversity of the WitwatersrandJohannesburgWits 2050South Africa Sustainable Energy and Environment research Group School of Chemical EngineeringUniversity of WitwatersrandPO Box 3JohannesburgWits 2050South Africa

Hydrothermal carbonization(HTC)technologies for p.o.ucing value-added carbonaceous material(hydrochar)from coal waste and sewage sludge(SS)waste might be a long-term recycling strategy for hydrogen storage applications,cutting disposal costs and solving waste disposal *** this study,hydrochars(HC)with high carbon content were p.o.uced using a combination of optimal HTC(HTC and Co-HTC)and chemical activation of coal tailings(CT),coal slurry(CS),and a mixture of coal discard and sewage sludge(CB).At 850℃and 800℃,respectively,with a KoH/HC ratio of 4:1 and a residence time of 135 min,activated carbons(ACs)with the highest Brunauer–Emmett–Teller specific surface(S_(BET))of 2299.25 m^(2)g^(−1)and 2243.57 m^(2)g^(−1)were *** hydrogen adsorption capability of the p.o.uced ACs was further studied using gas adsorption isotherms at 77 *** 35 bars,the values of hydrogen adsorbed onto AC-HCT(AC obtained from HTC of CT),AC-HCS(AC obtained from HTC of CS),and AC-HCB(AC obtained from HTC of the blending of coal discard(CD)and SS)were app.o.imately 6.12%,6.8%,and 6.57%in weight,***,the cost of p.o.ucing synthetic ACs for hydrogen storage is equivalent to the cost of commercial ***,the high p.o.ortion of carbon retained(>70%)in ACs synthesized by HTC from CD and SS precursors should restrict their potential carbon emissions.

关键词： Hydrothermal carbonization Coal slurry Coal tailing Sewage sludge Hydrogen storage Activated carbons Carbon emissions p.o.uction cost

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Ultra-broadband metamaterial absorbers from long to very long infrared regime

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Light(Science & Applications) 2021年第8期10卷 1462-1473页

作者： Yu Zhou Zheng Qin Zhongzhu Liang Dejia Meng Haiyang Xu David R.Smith Yichun Liu State Key Laboratory of Applied optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of Sciences130033 ChangchunJilinChina. University of Chinese Academy of Sciences 100049 BeijingChina. Center for Advanced op.o.lectronic Functional Materials research and Key Laboratory of UV Light-Emitting Materials and Technology of Ministry of Education College of PhysicsNortheast Normal University130024 ChangchunChina. Center for Metamaterials and Integrated plasmonics Duke UniversityP.O.Box 90291DurhamNC 27708USA

Broadband metamaterials absorbers with high absorption,ultrathin thickness and easy configurations are in great demand for many potential *** this paper,we first analyse the coupling resonances in a Ti/Ge/Ti three-layer absorber,which can realise broadband absorption from 8 to 12 *** we experimentally demonstrate two types of absorbers based on the Ti/Ge/Si_(3)N_(4)/Ti *** taking advantage of coupling surface plasmon resonances and intrinsic absorption of lossy material Si_(3)N_(4),the average absorptions of two types of absorbers achieve almost 95%from 8 to 14μm(experiment result:78%from 6.5 to 13.5μm).In order to expand the absorption bandwidth,we further p.o.ose two Ti/Si/Sio_(2)/Ti absorbers which can absorb 92%and 87%of ultra-broadband light in the 14-30μm and 8-30μm spectral range,*** findings establish general and systematic strategies for guiding the design of metamaterial absorbers with excellent broadband absorption and pave the way for enhancing the optical performance in applications of infrared thermal emitters,imaging and p.o.odetectors.

关键词： absorber absorption coupling

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Is machine learning redefining the perovskite solar cells?

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Journal of Energy Chemistry 2022年第3期31卷 74-90,I0004页

作者： Nishi parikh Meera Karamta Neha Yadav Mohammad Mahdi Tavakoli Daniel p.o.howicz Seckin Akin Abul Kalam Soumitra Satapathi pankaj Yadav Department of Science School of TechnologyPandit Deendayal Energy UniversityGandhinagar 382007GujaratIndia Department of Electrical Engineering School of TechnologyPandit Deendayal Energy UniversityGandhinagar 382007GujaratIndia Department of Telecommunication Ministry of CommunicationMumbai LSAMumbai 400072MaharashtraIndia Department of Electrical Engineering and Computer Science Massachusetts Institute of TechnologyCambridgeMA 02139USA institute of physical Chemistry Polish Academy of SciencesKasprzaka 44/5201-224 WarsawPoland Department of metallurgical and Materials Engineering Karamanoglu Mehmetbey University70200 KaramanTurkey Department of Chemistry Faculty of ScienceKing Khalid UniversityAbha 61413P.O.Box 9004Saudi Arabia Department of physics Indian Institute of Technology RoorkeeRoorkeeHaridwarUttarakhand 247667India Department of Solar Energy School of TechnologyPandit Deendayal Energy UniversityGandhinagar 382007GujaratIndia

development of novel materials with desirable p.o.erties remains at the forefront of modern scientific *** learning(ML),a branch of artificial intelligence,has recently emerged as a powerful technology in op.o.lectronic devices for the prediction of various p.o.erties and rational design of *** halide perovskites(MHps)have been at the centre of attraction owing to their outstanding p.o.ophysical p.o.erties and rapid development in solar cell ***,the application of ML in the field of MHps is also getting much attention to optimize the fabrication p.o.ess and reduce the cost of ***,we comprehensively reviewed different applications of ML in the designing of both MHp absorber layers as well as complete perovskite solar cells(pSCs).At the end,the challenges of ML along with the possible future direction of research are *** believe that this review becomes an indispensable roadmap for optimizing materials composition and predicting design strategies in the field of perovskite technology in the future.

关键词： Machine learning Metal halide perovskites perovskite solar cell Lead free perovskites

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research of power Take-off System for “Sharp Eagle Ⅱ” Wave Energy Converter

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China ocean Engineering 2019年第5期33卷 618-627页

作者： YE Yin WANG Kun-lin YoU Ya-ge SHENG Song-wei Guangzhou institute of Energy Conversion Chinese Academy of Sciences Guangzhou 510640 China Key Laboratory of Renewable Energy Chinese Academy of Sciences Guangzhou 510640 China Guangdong p.o.incial Key Laboratory of New and Renewable Energy research and development Guangzhou 510640 China

The " Sharp Eagle” device is a wave energy converter of a hinged double floating body. The wave-absorbing floating body hinges on the semi-submerged floating body structure. Under the action of wave, the wave-absorbing floating body rotates around the hinge point, and the wave energy can be converted into kinetic energy. In this paper, the power take-off system of " Sharp Eagle Ⅱ” wave energy converter (the second generation of " Sharp Eagle”) was studied, which adopts the hydraulic type power take-off system. The 0-1 power generation mode was applied in this system to make the " Sharp Eagle Ⅱ” operate under various wave conditions. The principle of power generation was introduced in detail, and the power take-off system was simulated. Three groups of different movement period inputs were used to simulate three kinds of wave conditions, and the simulation results were obtained under three different working conditions. In addition, the p.o.otype of " Sharp Eagle Ⅱ” wave energy converter was tested on land and in real sea conditions. The experimental data have been collected, and the experimental data and simulation results were compared and validated. This work has laid a foundation for the design and application of the following " Sharp Eagle” series of devices.

关键词： Sharp Eagle Wave Energy Converter power take-off power generation mode hydraulic system

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Comparative study on transverse shrinkage, mechanical and metallurgical p.o.erties of AA2219 aluminium weld joints prepared by gas tungsten arc and gas metal arc welding p.o.esses

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Defence Technology（防务技术） 2015年第3期11卷 262-268页

作者： S.ARUNKUMAR p.RANGARAJAN K.DEVAKUMARAN p.SATHIYA Department of p.o.uction Engineering National Institute of Technology Welding research institute BHEL

Aluminium alloy AA2219 is a high strength alloy belonging to 2000 series. It has been widely used for aerospace applications, especially for construction of cryogenic fuel tank. However, arc welding of AA2219 material is very critical. The major p.o.lems that arise in arc welding of AA2219 are the adverse development of residual stresses and the re-distribution as well as dissolution of copper rich phase in the weld *** effects increase with increase in heat input. Thus, special attention was taken to especially thick section welding of AA2219-T87 aluminium alloy. Hence, the present work describes the 25 mm-thick AA2219-T87 aluminium alloy plate butt welded by GTAW and GMAW p.o.esses using multi-pass welding p.o.edure in double V groove design. The transverse shrinkage, conventional mechanical and metallurgical p.o.erties of both the locations on weld joints were studied. It is observed that the fair copper rich cellular(CRC) network is on Side-A of both the weldments. Further, it is noticed that, the severity of weld thermal cycle near to the fusion line of HAZ is reduced due to low heat input in GTAW p.o.ess which results in non dissolution of copper rich phase. Based on the mechanical and metallurgical p.o.erties it is inferred that GTAW p.o.ess is used to imp.o.e the aforementioned characteristics of weld joints in comparison to GMAW p.o.ess.

关键词：焊接工艺设计铝合金焊接冶金性能横向收缩性能对比金属机械天然气

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IEC61850 standard-based harmonic blocking scheme for power transformers

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p.o.ection and Control of Modern power Systems 2019年第1期4卷 123-137页

作者： Senthil Krishnamurthy Bwandakassy Elenga Baningobera Center for Substation Automation and Energy Management Systems(CSAEMS) DEECECape Peninsula University of TechnologyPO BOX 1906Bellville 7535South Africa

Transformer Differential and overcurrent schemes are traditionally used as main and backup p.o.ection respectively. The differential p.o.ection relay (SEL487E) has dedicated harmonic restraint function which blocks the relay tripping during the transformer magnetizing inrush conditions. However, the backup.o.ercurrent relay (SEL751A) applied to the transformer p.o.ection does not have harmonic restraint element and trip the overcurrent relay during the inrush conditions. Therefore, major contribution of this research work is the developed harmonic blocking scheme for transformer which uses element (87HB) of the transformer differential relay (SEL487E) to send an IEC61850 GooSE-based harmonic blocking signal to the backup.o.ercurrent relay (SEL751A) to inhibit from tripping during the transformer magnetizing inrush current conditions. The simulation results p.o.ed that IEC61850 standard-based p.o.ection scheme is faster than the hardwired signals. Therefore, the speed and reliability of the transformer scheme are imp.o.ed using the IEC61850 standard-based GooSE applications.

关键词： Transformer p.o.ection overcurrent p.o.ection Digital p.o.ection scheme Current differential p.o.ection Transformer magnetizing inrush current Harmonic blocking IEC 61850 GooSE message

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土壤和水酸化对于健康的危害:瑞典的研究项目

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人类环境杂志 1996年第8期25卷 526-530页

作者： Agneta oskarsson Gunnar Nordberg Mats Block Finn Rasmussen Rolf petterson Staffan Skerfving Marie Vahter Anders Wicklund Glynn Toxicology Ingrid oborn Marie-Louise Heikensten and Ann Thuvander Section for research on Environmental pollution research and 齐文同 Department of Food Hygiene Swedish University of Agricultural Sciences Department of Environmental Medicine Ume University S-901 87 Umea Sweden Department of Environmental Toxicology Uppsala University Norbyvgen 18 A S-752 36 Uppsala Sweden. institute of Environmental Medicine Karolinska Institute Box 210 S-171 77 Stockholm Sweden Department of paediatrics Central Hospital S-541 85 Skvde Sweden Department of occupational and Environmental Medicine University Hospital S-221 85 Lund Sweden institute of Environmental Medicine Karolinska Institute S-171 77 Stockholm Sweden Division The National Food Administration Box 622 S-751 26 Uppsala Sweden Department of Soil Sciences Swedish University of Agricultural Sciences S-750 07 Uppsala Sweden development Department Swedish National Environmental Protection Agency S-106 48 Stockholm Sweden

环境的酸化是一个全球性的问题。对于酸的沉降量大而水体和土壤的缓冲性能低的地区而言,酸化问题尤其严重。考虑到在土壤和水体中的酸的沉降物的相当大的影响,重要的是确定其对于人类健康可能有哪些危害及危害的程度。瑞典的环境保护机... 详细信息

环境的酸化是一个全球性的问题。对于酸的沉降量大而水体和土壤的缓冲性能低的地区而言,酸化问题尤其严重。考虑到在土壤和水体中的酸的沉降物的相当大的影响,重要的是确定其对于人类健康可能有哪些危害及危害的程度。瑞典的环境保护机构从1991年开始进行一项五年研究计划,以研究酸的沉降对于人类健康的危害。这个研究项目的研究内容集中于酸沉降的间接效应。这些间接效应主要是由于微量元素的迁移性改变的结果,导致在大多数情况下使微量元素的含量增加,而在少数情况下微量元素则减少。通过食物链,人体所摄入的有毒元素及必需元素的量可能发生改变。此项研究项目的目标是查明:①酸化作用在多大程度上改变人类所接触的各种元素,包括总的数量级或者其化学状态;②这些改变对于人类的健康有什么作用。此项研究的目的则是尽早发现其对于健康的作用,以求能够防止其对于人类健康的恶劣影响。尽管有一些迹象表明,有毒元素的暴露,如钙、甲基汞和铅等,以及有益元素如硒等的吸收都有可能受到酸的沉降的影响,但目前尚无确凿的证据说明其对于人类的健康有所危害。然而,现有的资料清楚表明,安全度是很小的,应当尽量努力将暴露于一切有毒元素的来源保持在尽可能低的水平上。

关键词：土壤酸化水酸化健康酸化

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Superior mechanical p.o.erties and strengthening mechanisms of lightweight AlxCrNbVMo refractory high-entropy alloys(x=0,0.5,1.0)fabricated by the powder metallurgy p.o.ess

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Journal of Materials Science & Technology 2021年第10期69卷 32-41页

作者： Byungchul Kang Taeyeong Kong Ho Jin Ryu Soon Hyung Hong Department of Material Science and Engineering Korea Advanced Institute of Science and Technology(KAIST)291 Daehak-roYuseong-guDaejeon 34141Republic of Korea Department of Nuclear and Quantum Engineering Korea Advanced Institute of Science and Technology(KAIST)291 Daehak-roYuseong-guDaejeon 34141Republic of Korea

Light and strong AlxCrNbVMo(x=0,0.5,and 1.0)refractory high-entropy alloys(RHEAs)were designed and fabricated via a the powder metallurgical *** microstructure of the AlxCrNbVMo alloys consisted of a single BCC crystalline structure with a sub-micron grain size of 2-3μm,and small amounts(ol.%)of fine oxide *** homogeneous microstructure,without chemical segregation or micropores was achieved via high-energy ball milling and spark-plasma *** alloys exhibited superior mechanical p.o.erties at 25 and 1000℃compared to those of other ***,CrNbVMo alloy showed a yield strength of 2743 Mpa at room ***,the yield strength of the CrNbVMo alloy at 1000℃was 1513 *** specific yield strength of the CrNbVMo alloy was increased by 27%and 87%at 25 and 1000℃,respectively,compared to the AlMo_(0.5) NbTa_(0.5)TiZr RHEA,which exhibited so far the highest specific yield strength among the cast *** addition of Al to CrNbVMo alloy was advantageous in reducing its reduce density to below 8.0 g/cm^(3),while the elastic modulus decreased due to the much lower elastic modulus of Al compared to that of the CrNbVMo *** analysis of the strengthening contributions,showed that the solid solution strengthening,arising from a large misfit effect due to the size and modulus,and the high shear modulus of matrix,was revealed to predominant strengthening mechanism,accounting for over 50%of the yield strength of the AlxCrNbVMo RHEAs.

关键词： High-entropy alloy powder metallurgy Refractory Strengthening mechanisms oxide dispersoids

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Three-dimensional characteristics of mesoscale eddies simulated by a regional model in the northwestern pacific ocean during 2000–2008

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Acta oceanologica Sinica 2022年第10期41卷 74-93页

作者： Guijing Yang Xiayan Lin Guoqing Han Yu Liu Gengxin Chen Jianhui Wang Marine Science and Technology College Zhejiang Ocean UniversityZhoushan316000China State Key Laboratory of Satellite ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou310012China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519082China State Key Laboratory of Tropical oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou510301China

Mesoscale eddies play vital roles in ocean *** previous studies focused on eddy surface features and individual three-dimensional(3D)eddy cases in the northwestern pacific ocean,the analysis of unique eddy3D regional characteristics is still lacking.A 3D eddy detection scheme is applied to 9 years(2000-2008)of eddyresolving Regional ocean Modeling System(RoMS)output to obtain a 3D eddy dataset from the surface to a depth of 1000 m in the northwestern pacific ocean(15°-35°N,120°-145°E).The 3D characteristics of mesoscale eddies are analyzed in two regions,namely,box1(Subtropical Countercurrent,15°-25°N,120°-145°E)and box2(Southern Kuroshio Extension,25°-35°N,120°-145°E).In box1,the current is characterized by strong vertical shear and weak horizontal *** box2,the current is characterized by the strong Kuroshio,topographic effect,and the westward p.o.agation of Rossby *** results indicate the importance of baroclinic instability in box1,whereas in box2,both the barotropic and baroclinic instability are ***,the mesoscale eddies’p.o.erties in box1 and box2 are *** eddies in box1 have larger number and radius but a shorter *** contrast,box2 has fewer eddies,which have smaller radius but longer ***,more eddies are detected at the subsurface than at the surface in both regions;the depth of 650 m is the turning point in *** this depth,the number of cyclonic eddies(CEs)is larger than that of anticyclonic eddies(AEs).In box2,the number of CEs is dominant *** kinetic energy(EKE)and mean normalized relative vorticity in box2are significantly higher than those in *** increasing depth,the attenuation trend of EKE and relative vorticity of box1 become greater than those of ***,the upper ocean(about 300 m in depth)contains 68.6%of the eddies(instantaneous eddy).only 16.6%of the eddies extend to 1000 *** addition,about87%of the eddies are bowl-shaped eddies in the two reg

关键词： three-dimensional structures mesoscale eddies northwestern pacific ocean

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