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Journal of Magnesium and Alloys 2014年第1期2卷 20-26页

作者： D.Wu y.Q.Ma R.S.Chen W.Ke The Group of Magnesium and Their Applications Institute of Metal ResearchChinese Academy of Sciences62 Wencui RoadShenyang 110016China

The tensile testing bars of the Mg-2.7Nd-0.6Zn-0.5Zr(wt.%)alloy were prepared by sand *** effect of solution temperature and aging time on the microstructures and mechanical properties were *** as-cast alloy was composed ofαmagnesium matrix and Mg12Nd eutectic *** solution treatment at 500℃ for 18 h,the volume fraction of eutectic compounds decreased from∼7.8%to∼2.3%,and some small Zr-containing particles were observed to precipitate at grain *** the solution temperature increased to 525℃ for 14 h,most of the eutectic compounds dissolved into the ***-aged at 200℃ for 12 h,fineβ″particles was the dominant strengthening *** yield strength,ultimate tensile strength and elongation in the peak-aged condition were 191 MPa,258 MPa and 4.2%,***,the Mg-2.7Nd-0.6Zn-0.5Zr alloys under different heat treatment conditions exhibited different tensile fracture modes.

关键词： Magnesium alloy Sand-cast Heat treatment Microstructure Mechanical properties

Dielectric response and percolation behavior of Ni–P(VDF–TrFE) nanocomposites

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Journal of Advanced Dielectrics 2017年第3期7卷 1-8页

作者： Lin Zhang Patrick Bass Guan Wang yang Tong Zhuo Xu Z-y.Cheng Materials Research and Education Center Auburn University Auburn AL 36849USA Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education and International Center for Dielectric Research Xi'an Jiaotong University Xi'an 710049P.R.China

Conductor–dielectric 0–3 nanocomposites using spherical nickel nanoparticles as filler and poly(vinylidene fluoride–trifluoroethylene)70/30 mol.%as matrix are prepared using a newly developed process that combines a solution cast and a hotpressing method with a unique configuration and creates a uniform microstructure in the *** uniform microstructure results in a high percolation threshold’φc(>55 vol.%).The dielectric properties of the nanocomposites at different frequencies over a temperature range from -70℃ to 135℃ are *** results indicate that the composites exhibit a lower electrical conductivity than the polymer *** is found that the nanocomposites can exhibit an ultra-high dielectric constant,more than 1500 with a loss of about 1.0 at 1 kHz,when the Ni content(53 vol.%)is close to percolation *** the nanocomposites with 50 vol.%Ni particles,a dielectric constant more than 600 with a loss less than 0.2 is *** is concluded that the loss including high loss is dominated by polarization process rather than the electrical *** is also found that the appearance of Ni particles has a strong influence on the crystallization process in the polymer matrix so that the polymer is converted from a typical ferroelectric to a relaxor *** is also demonstrated that the widely used relationship between the dielectric constant and the composition of the composites may not be valid.

关键词： Composite dielectric conductivity percolation.

Self-assembled monolayer enabling improved buried interfaces in blade-coated perovskite solar cells for high efficiency and stability

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Nano Research Energy 2022年第1期1卷 14-21页

作者： Jie Zeng Leyu Bi yuanhang Cheng Baomin Xu Alex K.-y.Jen Department of Materials Science and Engineering City University of Hong KongKowloon 999077Hong KongChina Department of Chemistry City University of Hong KongKowloon 999077Hong KongChina Hong Kong Institute for Clean Energy City University of Hong KongKowloon 999077Hong KongChina Department of Materials Science and Engineering Guangdong-Hong Kong-Macao Joint Laboratory for Photonic-Thermal-Electrical Energy Materials and DevicesSouthern University of Science and TechnologyShenzhen 518055China

Despite the rapidly increased power conversion efficiency(PCE)of perovskite solar cells(PVSCs),it is still quite challenging to bring such promising photovoltaic technology to *** of the challenges is the upscaling from small-sized lab devices to large-scale modules or panels for ***,most of the efficient inverted PVSCs are fabricated on top of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine](PTAA),which is a commonly used hole-transporting material,using spin-coating method to be incompatible with large-scale film ***,it is important to develop proper coating methods such as blade-coating or slot-die coating that can be compatible for producing large-area,high-quality perovskite thin *** is found that due to the poor wettability of PTAA,the blade-coated perovskite films on PTAA surface are often inhomogeneous with large number of voids at the buried interface of the perovskite *** solve this problem,self-assembled monolayer(SAM)-based hole-extraction layer(HEL)with tunable headgroups on top of the SAM can be modified to provide better wettability and facilitate better interactions with the perovskite coated on top to passivate the interfacial *** more hydrophilic SAM surface can also facilitate the nucleation and growth of perovskite films fabricated by blade-coating methods,forming a compact and uniform buried *** addition,the SAM molecules can also be modified so their highest occupied molecular orbital(HOMO)levels can have a better energy alignment with the valence band maxima(VBM)of *** by the high-quality buried interface of perovskite on SAM-based substrate,the champion device shows a PCE of 18.47%and 14.64%for the devices with active areas of 0.105 cm^(2) and 1.008 cm^(2),*** addition,the SAM-based device exhibits decent stability,which can maintain 90%of its initial efficiency after continuous operation for over 500 h at 40℃ in inert ***

关键词： self-assembled monolayer buried interface perovskite solar cells upscaling blade-coating

Effect of pre-deformation on microstructure and mechanical properties of WE43 magnesium alloy II: Aging at 250 and 300℃

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Journal of Magnesium and Alloys 2020年第1期8卷 103-110页

作者： y.H.Kang Z.H.Huang S.C.Wang H.yan R.S.Chen J.C.Huang Guangdong-Hong Kong Joint Research and Development Center on Advanced Manufacturing Technology for Light Alloys Guangdong Institute of Materials and ProcessingGuangzhou 510650China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016China Hong Kong Institute for Advanced Study Department of Materials Science and EngineeringCity University of Hong KongHong KongChina

In this work,the microstructural evolution and mechanical properties of a pre-deformed WE43 magnesium alloy when aged at 250 and 300℃ were further *** is found that the abundant deformation twins introduced by pre-deformation were maintained within the alloy during the aging *** particles formed at the twin boundaries and coarsened with aging time,especially at 300℃.When peak-aged at 250℃,the fine metastable β'''and β' precipitates formed in the un-deformed alloy have been transformed into relatively large β1 and β precipitates by the *** peak-aged at 300℃,the pre-deformation obviously refined the β *** properties indicate that pre-deformation can increase the yield strength by 19MPa and 54MPa for the peak-aged alloy at 250℃ and 300℃,respectively,and will not obviously deteriorate the tensile elongations.

关键词： WE43 magnesium alloy Pre-deformation Aging Microstructure Mechanical properties

Properties of a Scale of Self-Care Behaviors Facing COVID-19:An Exploratory Analysis in a Sample of University Students in Huanuco,Peru

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International Journal of Mental Health Promotion 2022年第6期24卷 959-974页

作者： Mely Ruiz-Aquino Viter Gerson Carlos Trinidad Aldo Alvarez-Risco Jaime A.yáñez Universidad de Huánuco Facultad de Ciencias de la SaludHuánucoPeru EsSalud Hospital Bicentenario de JaujaHuancayoPeru Universidad de Lima Facultad de Ciencias Empresariales y EconomicasCarrera de Negocios InternacionalesLimaPeru Universidad Norbert Wiener Vicerrectorado de InvestigaciónLimaPeru Teoma Global Gerencia Corporativa de Asuntos Científicos y RegulatoriosLimaPeru

The general objective of this article was to construct and describe the psychometric properties of a scale of selfcare behaviors against *** was a descriptive,cross-sectional,psychometric validation study of a scale created to measure self-care behaviors in relation to COVID-19 in a total sample of 333 probabilistically *** validity was evaluated by a review of 10 experts and quantitative validity by means of exploratory factor analysis using the principal components *** consistency was measured with Cronbach’s alpha twice and the test-retest was evaluated by calculating the intraclass *** final scale consisted of 29 *** Kaiser-Meyer-Olkin test of adequacy yielded a value of 0.926,and the Bartlett’s test of sphericity X^(2)=4611 with a p-valuey the three retained factors with a total of 29 items was 50.03%.The Cronbach’s alpha internal consistency evaluation yielded an initial value of 0.923 and,in a second evaluation,showed a value of *** addition,the intraclass coefficient in the test-retest yielded a value of *** instrument created and validated possessed the necessary conditions as a useful and reliable tool for measuring self-care behaviors in relation to COVID-19 in a population of university students and it is important that it can be applied in other regions of the world.

关键词： COVID-19 Peru self-care physical health social health mental health validation instrument

On the solar activity dependence of midnight equatorial plasma bubbles during June solstice periods

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Earth and Planetary Physics 2021年第5期5卷 378-386页

作者： K.K.Ajith S.Tulasi Ram GuoZhu Li M.yamamoto K.Hozumi C.y.yatini P.Supnithi Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Indian Institute of Geomagnetism MumbaiIndia Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Research Institute for Sustainable Humanosphere Kyoto UniversityUjiJapan National Institute of Information and Communications Technology TokyoJapan Space Science Center Indonesian National Institute of Aeronautics and SpaceIndonesia School of Engineering King Mongkut’s Institute of Technology LadkrabangChalongkrung RdLadkrabang10520 BangkokThailand

The occurrence of midnight Equatorial Plasma Bubbles(EPBs)during the June solstice period of the ascending phase of solar cycle 24,from 2010 to 2014,was studied using data from the 47 MHz Equatorial Atmosphere Radar(EAR)at Kototabang,*** analysis shows that the occurrence of midnight hour EPBs was at its maximum during the low solar activity year 2010 and monotonically decreased thereafter with increasing solar *** of the dependence of midnight hour EPB occurrence on solar activity were investigated using SAMI2 model simulation with a realistic input of E×B drift velocity data obtained from the CINDI-IVM onboard the C/NOFS *** obtained from term-by-term analysis of the flux tube integrated linear growth rate of RT instability indicate that the formation of a high flux tube electron content height gradient(steep vertical gradient)region at higher altitudes,due to the elevated F layer,is the key factor enhancing the growth rate of RT instability during low solar activity June *** factors are discussed in light of the relatively weak westward zonal electric field in the presence of the equatorward neutral wind and north-to-south transequatorial wind around the midnight hours of low solar activity June *** discussed are the initial seeding of RT instability by MSTIDs and how the threshold height required for EPB development varies with solar activity.

关键词： equatorial plasma bubbles equatorial ionosphere ionospheric instabilities and irregularities

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ZnO薄膜非线性光学特性的实验研究

光学精密工程 2005年第3期13卷 265-271页

作者：刘成有宁丹 B.P.Zhang y.Segawa 通化师范学院物理系 Photodynamics Research Center The Institute of Physical and Chemical ResearchRIKEN5191399 AobaAramakiAoba kuSendai9800845Japan

利用金属有机化学气相沉积(MOCVD)技术在蓝宝石衬底上生长一层高质量的ZnO薄膜。为了考察沉积温度对样品的非线性特性的影响,在200～500℃生长了一系列ZnO薄膜。用X射线衍射谱(XRD)及扫描电镜(SEM)对样品结构进行了评价。以Nd:yAG激光... 详细信息

利用金属有机化学气相沉积(MOCVD)技术在蓝宝石衬底上生长一层高质量的ZnO薄膜。为了考察沉积温度对样品的非线性特性的影响,在200～500℃生长了一系列ZnO薄膜。用X射线衍射谱(XRD)及扫描电镜(SEM)对样品结构进行了评价。以Nd:yAG激光器输出的1.06μm的激光为基频光,对ZnO薄膜样品的二阶及三阶非线性光学特性进行了实验研究。实验发现,对于250℃沉积温度的样品有较强的非线性效应,实验测得的二阶非线性极化张量χ(2)ZZZ=9.2pm/V,三阶有效非线性系数χ(3)=5.28×10-20m2/V2。

关键词：二次谐波振荡金属有机化学气相沉积二阶极化率三阶极化率沉积温度

Experimental Observables on Nuclear Liquid Gas Phase Transition

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复旦学报（自然科学版） 2007年第1期46卷 33-40页

作者： y. G. Ma Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China

Progress on nuclear liquid gas phase transition （LGPT） or critical behavior has been simply reviewed and some signals of LGPT in heavy ion collisions, especially in NIMROD data, are focused. These signals include the power-law charge distribution, the largest fluctuation of the fragment observables, the nuclear Zipf law, caloric curve and critical exponent analysis etc.

关键词：离子碰撞热量曲线临界指数原子核液体气体相转变能量

MULTI-PEAK MATCH INTENSITy RATIO METHOD OF QUANTI-TATIVE X-RAy DIFFRACTION PHASE ANALySIS

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Acta Metallurgica Sinica(English Letters) 2003年第6期16卷 489-494页

作者： G. Chu, y.F. Cong and H.J. youResearch Center of Analysis and Test, Liaoning University of Petroleum & Chemical Technology, Fushun 113001, China Res. Ctr. of Analysis and Test Liaoning Univ. of Petrochem. Tehnol. Fushun 113001 China

A new method for quantitative phase analysis is proposed by using X-ray diffraction multi-peak match intensity ratio. This method can obtain the multi-peak match intensity ratio among each phase in the mixture sample by using all diffraction peak data in the mixture sample X-ray diffraction spectrum and combining the relative intensity distribution data of each phase standard peak in JCPDS card to carry on the least square method regression analysis. It is benefit to improve the precision of quantitative phase analysis that the given single line ratio which is usually adopted is taken the place of the multi-peak match intensity ratio and is used in X-ray diffraction quantitative phase analysis of the mixture sample. By analyzing four-group mixture sample, adopting multi-peak match intensity ratio and X-ray diffraction quantitative phase analysis principle of combining the adiabatic and matrix flushing method, it is tested that the experimental results are identical with theory.

关键词： X-ray diffraction multi-peak match intensity ratio quantitative phase analysis

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等离子体浸没离子注入绝缘材料的研究

核技术 2006年第5期29卷 335-338页

作者：田修波杨士勤 Ricky K y Fu Paul K Chu 哈尔滨工业大学材料科学与工程学院哈尔滨150001 香港城市大学物理及材料科学系

等离子体浸没离子注入是一种新形式的离子注入技术,是利用负偏压工件周围形成的等离子体鞘层进行离子加速、进而获得离子注入。等离子体注入的前提条件是工件导电,因此对于绝缘材料的等离子体注入可能存在问题。本文从理论和实际处理的... 详细信息

等离子体浸没离子注入是一种新形式的离子注入技术,是利用负偏压工件周围形成的等离子体鞘层进行离子加速、进而获得离子注入。等离子体注入的前提条件是工件导电,因此对于绝缘材料的等离子体注入可能存在问题。本文从理论和实际处理的角度论证了绝缘材料等离子体注入的可能性、可操作性,并给出了一些实际例证。

关键词：等离子体离子注入绝缘材料鞘层表面充电