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硅酸盐学报 1990年第2期18卷 179-183页

作者：叶铭勋 r.d.hooton 南京水利科学研究院多伦多大学

本文用3种不同的试样制备方法和3种测孔方法分别测定了加矿渣、粉煤灰和硅灰等掺合料的硬化水泥浆体孔隙率。结果表明,试样制备方法和孔隙率测定方法一样,都会影响孔隙率的测定结果,掺加掺合料以后,这种影响更为显著。

关键词：硬化水泥浆体孔隙率矿渣粉煤灰

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水泥石孔隙率测定方法的研究

水利水运科学研究 1991年第1期 63-73页

作者：叶铭勋 r.d.hooton 南京水利科学研究院材料结构研究所加拿大多伦多大学土木系

本文研究了几种测定水泥石孔隙率的方法,选用了硅酸盐水泥,水灰比为O.3、O.5和0.7,龄期为7、28、91和182天。用饱水法、溶剂法、氦流法和压汞法测定孔隙率。试样的制备用烘干干燥、溶剂取代法干燥和冷冻法干燥。试验结果表明,试样制备... 详细信息

本文研究了几种测定水泥石孔隙率的方法,选用了硅酸盐水泥,水灰比为O.3、O.5和0.7,龄期为7、28、91和182天。用饱水法、溶剂法、氦流法和压汞法测定孔隙率。试样的制备用烘干干燥、溶剂取代法干燥和冷冻法干燥。试验结果表明,试样制备方法和孔隙率测定方法,都对孔隙率测定有较大的影响。

关键词：水泥石孔隙率测定

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高温处理砂浆中再生钙矾石的形成与膨胀

国外建材科技 1994年第1期15卷 23-26页

作者： r.d.hooton 何其捷加拿大

本文采用加拿大生产的含有较高C_3A的水泥对高温处理的砂浆中再生钙矾石的形成与膨胀机理进行了研究。由膨胀现象、x-射线衍射分析和孔洞结构测定的结果表明,如果砂浆在高温下(>80℃)进行预处理,水泥中f-石膏可与单硫酸盐反应形成再生... 详细信息

本文采用加拿大生产的含有较高C_3A的水泥对高温处理的砂浆中再生钙矾石的形成与膨胀机理进行了研究。由膨胀现象、x-射线衍射分析和孔洞结构测定的结果表明,如果砂浆在高温下(>80℃)进行预处理,水泥中f-石膏可与单硫酸盐反应形成再生钙矾石并产生滞后膨胀。这种现象只有在80℃养护干燥时才能观察到。本文提出了再生钙矾石的形成与膨胀的机理。显而易见,水泥中(SO_3)~2/Al_2O_3(eff)之比和干燥过程是控制再生钙矾石的形成与膨胀的主要因素。

关键词：砂浆钙矾石再生膨胀形成高温

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研究与标准之间的桥梁(上)

商品混凝土 2009年第8期 66-68页

作者： r.d.hooton 郭晓饶美娟刘数华加拿大多伦多大学武汉大学水资源与水电工程科学国家重点实验室武汉430072

标准的发展和持续存在有利于商业往来。确定材料的最低要求,采用标准测试方法来判定这些要求范围。水泥材料和混凝土的其他成分的说明需参考混凝土的规范,这些规范同时指导着建筑标准。对标准最常见的抱怨是它不能及时反映新的研究发明... 详细信息

标准的发展和持续存在有利于商业往来。确定材料的最低要求,采用标准测试方法来判定这些要求范围。水泥材料和混凝土的其他成分的说明需参考混凝土的规范,这些规范同时指导着建筑标准。对标准最常见的抱怨是它不能及时反映新的研究发明,落后于新的材料发展和建筑实践。然而,随着需要的提升和新的测试方法的增加或者标准测试要求的确定,标准一直在发展。另一个抱怨是标准应转化为以性能为基础,以便于不再限制材料的革新和建筑方法的发展。值得注意的是,许多标准的制定机构发展了一个统一的标准,如ASTM和CSA;ASTM和CSA提供了一系列的不同利益的平衡性代表,特别是包括了生产者和用户,也包括政府组织机构的利益代表。作为这种平衡的结果,单独的一个组织无法改变标准而损害大部分人的利益。在这种情况下,一些曾经的和最新的关于胶凝材料的标准发展以及未来的发展方向构想应运而生。与此同时,许多国际化标准被提及,但本文主要讨论的是北美标准。

关键词：水泥混凝土组成抗硫酸盐侵蚀标准

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研究与标准之间的桥梁(下)

商品混凝土 2009年第9期 71-75页

作者： r.d.hooton 郭晓饶美娟刘数华加拿大多伦多大学武汉大学水资源与水电工程科学国家重点实验室武汉430072

2.8抗硫酸盐侵蚀测试目前北美抗硫酸盐侵蚀标准包括限制水胶比、最低强度以及水泥的组成和膨胀率。从20世纪20年代,甚至在化学反应未被理解之前,人们就认识到低W/C和低浓度结合水含量的混凝土混合物对于抵抗硫酸侵蚀具有重要的作用。此... 详细信息

2.8抗硫酸盐侵蚀测试目前北美抗硫酸盐侵蚀标准包括限制水胶比、最低强度以及水泥的组成和膨胀率。从20世纪20年代,甚至在化学反应未被理解之前,人们就认识到低W/C和低浓度结合水含量的混凝土混合物对于抵抗硫酸侵蚀具有重要的作用。此后不久,人们意识到了C3A水泥的不足之处。

关键词：硫酸盐侵蚀混凝土掺合料硅灰混合水泥胶凝材料外加剂水泥标准耐久性设计凝结时间性能测试

Simple collective model for nuclear chiral mode

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Frontiers of physics 2024年第2期19卷 1-5页

作者： r.V.Jolos E.A.Kolganova d.r.Khamitova Joint Institute for Nuclear research 141980 DubnaMoscow regionRussia dubna State University 141982 DubnaMoscow RegionRussia

A simple semi-analytical collective model that takes into account the limitations of the variation interval of the collective variable is suggested to describe the chiral dynamics in triaxial odd−odd nuclei with a fixed particle−hole *** collective Hamiltonian is constructed with the potential energy obtained using the postulated ansatz for the wave function symmetric with respect to chiral *** diagonalizing the collective Hamiltonian the wave functions of the lowest states are obtained and the evolution of the energy splitting of the chiral doublets in transition from chiral vibration to chiral rotation regime is demonstrated.

关键词： collective model nuclear chiral

Ion heat transport in electron cyclotron resonance heated L-mode plasma on the T-10 tokamak

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Plasma Science and Technology 2024年第4期26卷 52-60页

作者： V.A.KrUPIN M.r.NUrGALIEV A.r.NEMETS I.A.ZEMTSOV S.d.SUNTSOV T.B.MYALTON d.S.SErGEEV N.A.SOLOVEV d.V.SArYCHEV d.V.rYJAKOV S.N.TUGArINOV N.N.NAUMENKO National research Centre“Kurchatov Institute” Moscow 123182Russia Bauman Moscow State Technical University Moscow 105005Russia Institution“Project Center ITEr” Moscow 123098Russia JSC“SOLAr” Minsk 220034Belarus

Anomalous ion heat transport is analyzed in the T-10 tokamak plasma heated with electron cyclotron resonance heating(ECrH) in second-harmonic extra-ordinary mode. Predictive modeling with empirical scaling for Ohmical heat conductivity shows that in ECrH plasmas the calculated ion temperature could be overestimated, so an increase of anomalous ion heat transport is required. To study this effect two scans are presented: over the EC resonance position and over the ECrH power. The EC resonance position varies from the high-field side to the low-field side by variation of the toroidal magnetic field. The scan over the heating power is presented with on-axis and mixed ECrH regimes. discharges with high anomalous ion heat transport are obtained in all considered regimes. In these discharges the power balance ion heat conductivity exceeds the neoclassical level by up to 10 times. The high ion heat transport regimes are distinguished by three parameters: the ratio Te/Ti, the normalized electron density gradient r/■, and the ion–ion collisionality νii~*. The combination of high Te/Ti, high νii~*, and r/■=6-10 results in values of normalized anomalous ion heat fluxes up to 10 times higher than in the low transport scenario.

关键词： tokamak L-mode electron cyclotron resonance heating ion heat transport

Uncovering Microstructure-Property relationship in Ni-Alloyed Fe-Mn-Al-C Low-density Steel Treated by Hot-rolling and Air-Cooling Process

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 713-725页

作者： Xiaoliang Jia Guhui Gao Xiaolu Gui Chun Feng r.d.K.Misra Bingzhe Bai School of Mechanical Electronicand Control EngineeringBeijing Jiaotong UniversityBeijing100044China CNPC Tubular Goods research Institute Xi’an710077China Laboratory for Excellence in Advanced Steel research University of Texas at El PasoEl PasoTX79968-0521USA School of Material Science and Engineering Key Laboratory of Advanced Materials of Ministry of EducationTsinghua UniversityBeijing100084China

This paper focuses on the relationship between the microstructure and tensile properties of Fe-Mn-Al-C low-density high-strength steel processes by hot-rolling and air-cooling process. The microstructure analysis reveals that the combination of hot-rolling and air-cooling results in the formation of heterogeneous structures comprising different-sized γ and B_(2) phases in the low-density steel with the addition of nickel (Ni). The addition of Ni promotes the formation of the B_(2) phase and induces the pinning of B_(2) phase particles at the γ grain boundaries. This pinning effect effectively hinders the growth of the γ grains, leading to grain refinement. The tensile test results demonstrate that LdS-5Ni (low-density steel, LdS) exhibits excellent high strength and ductility combination, e.g., a tensile strength of 1535 MPa, yield strength of 1482 MPa, and elongation of 23.3%. These remarkable mechanical properties are primarily attributed to the combined strengthening contributions of grain refinement and duplex nano-sized second-phase precipitation hardening.

关键词： Low-density steel Microstructure B_(2)phase κ-Carbide Tensile properties

The magnetosheath at high spectral resolution

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Earth and Planetary Physics 2024年第1期8卷 234-246页

作者： K.d.Küntz d.Koutroumpa W.r.dunn A.Foster F.S.Porter d.G.Sibeck B.Walsh The Henry A.rowland department of Physics and Astronomy Johns Hopkins University3701 San Martin DriveBaltimoreMD21218USA NASA Goddard Space Flight Center 8800 Greenbelt RoadGreenbeltMD 20771USA LATMOS-OVSQ CNRSUVSQ Paris-SaclaySorbonne Université11 Boulevard d’Alembert78280GuyancourtFrance department of Physics and Astronomy University College LondonLondonUK The Centre for Planetary Science at UCL/Birkbeck Gower StreetLondon WC1E 6BTUK Center for Astrophysics Harvard University&Smithsonian Institution60 Garden StreetCambridgeMA 02138USA Center for Space Physics Boston University110 Cummington MallBostonMAUSA

While we eagerly anticipate SMILE’s(Solar wind Magnetosphere Ionosphere Link Explorer)unprecedented X-ray observations of the Earth’s magnetosheath and the initiation of a new era of magnetospheric research,it seems appropriate to look ahead to the abilities of the next generation of astrophysics *** these,the Line Emission Mapper(LEM),a large aperture micro-calorimeter based mission,is currently planned to be able to observe the magnetosheath at high spectral resolution(~2 eV).With a field of view of~30′,LEM will allow higher spatial resolution and higher cadence measurement of the motion of a very small portion of the magnetopause over relatively short periods of time(multiple hours),complementing SMILE’s global ***’s strength is its spectral *** will be able to measure the abundance of a broad range of elements and ionization states,many of which are inaccessible to current in situ instruments,and will be able to separate the emission from the magnetosheath from the emission from the cosmic X-ray background using the difference in their relative velocities.

关键词： magnetosheath charge exchange solar wind abundances

Malargüe Site remediation:A Successful Solution for Uranium Mill Tailings

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原子能科学技术 2024年第10期58卷 2088-2094页

作者： BArArI E díAZ J G GIOMIA KEMPF r A National Atomic Energy Commission Av.Del Libertador 8250Ciudad Autónoma de Buenos AiresC1429BNPArgentina

Comisión Nacional de Energía Atómica (CNEA) has the responsibility for restoring uranium mining facilities once the operations have ***,within its Environmental Program and in compliance with its legal responsibilities,decides to implement a restoration project for all sites related to the mining and processing of uranium *** Malargüe Site is located within the Province of Mendoza in the city of Malargü*** is the first site to successfully complete its *** activities consist of relocation of tailings to an engineering *** tailings management(encapsulation) and rehabilitation of the area was finished in June *** remediation alternative for the ore tailings was selected after conducting comparative studies and submitted the project to the society for *** objective of the encapsulation of the mineral tails is to isolate them from the environment,also proceeding with the decontamination and rehabilitation of the area (landscaping,post-closure monitoring and 20 years monitoring period).Encapsulation consisted of the construction of a containment cell for the mine tailings,to isolate them and prevent pollutants from entering the environment through the transfer *** clean the impacted areas,the soil was removed,it was incorporated into the encapsulation,and the filling was carried out with natural soils from the *** prevents radon transfer to the environment,as ^(222)ra is an alpha emitter with a half-life of four days,which produces its own radioactive *** progeny are solids,and when a ^(222)ra nucleus emits an alpha particle into the air,the resulting ^(218)Po nucleus,momentarily electrically charged,adheres to any dust *** prevents the discharge into the air containing radon and also containing dust particles charged with intensely radioactive radon *** tasks mentioned make it possible to decrease radon emanation,reduce radiological risks to the public and pre

关键词： remediation radionuclide transfer tailings encapsulation solution sustainable