Effect of nano-silica on the hydration and microstructure development of Ultra-High Performance Conc

纳米氧化铝对硅酸三钙水化性能的影响张京波;王琦;宋鹏;杨中喜;卢露【摘要】为了探究纳米氧化铝(NA)对硅酸三钙(C3S)水化过程的影响,采用溶胶-凝胶法制备高纯C3S矿物,NA以不同的含量参与C3S水化;采用X射线衍射、扫描电子显微镜、水化量热分析及差热分析等测试手段,研究NA对C3S水化速率、水化产物及形貌和浆体强度等水化性能的影响.结果表明:NA能够促进C3S的的水化,尽管延迟了C3S诱导期的水化,但水化放热速率及放热总量均大于纯C3S的;NA的加入增加了C3S水化产物C-S-H凝胶和氢氧化钙(CH)晶体的含量,其中NA的质量分数为1％时CH晶体的质量增加率为8％,NA的质量分数为5％时C-S-H凝胶的增加率为4.1％;NA能够减少C3S水化浆体表面孔隙,使得浆体表面更加致密,水化程度更高;NA的质量分数为1％时C3S水化浆体试样的抗压强度最大,其28 d 抗压强度较纯C3S浆体试样的增加8％.【期刊名称】《济南大学学报（自然科学版）》【年(卷),期】2018(032)006【总页数】6页(P510-515)【关键词】纳米氧化铝;硅酸三钙;水化性能【作者】张京波;王琦;宋鹏;杨中喜;卢露【作者单位】济南大学材料科学与工程学院,山东济南 250022;济南大学材料科学与工程学院,山东济南 250022;济南大学材料科学与工程学院,山东济南250022;济南大学材料科学与工程学院,山东济南 250022;济南大学材料科学与工程学院,山东济南 250022【正文语种】中文【中图分类】TQ172.1纳米技术是一项具有革命性的技术革新，在能源、安全和信息技术等诸多领域得到了广泛的应用。

纳米材料具有活性高、颗粒细小和比表面积大等特性，近年来在水泥和混凝土中的应用越来越受到人们的重视[1-3]。

在水泥混凝土材料领域中研究最多的纳米材料主要是纳米二氧化硅、纳米碳酸钙、纳米氧化铝(NA)以及纳米二氧化钛等[4-9]。

第40卷第9期2021年9月硅㊀酸㊀盐㊀通㊀报BULLETIN OF THE CHINESE CERAMIC SOCIETY Vol.40㊀No.9September,2021磁铁矿防辐射超高性能混凝土制备及性能研究韩建军1,廖㊀党1,席壮民1,唐海超2,代崇阳3,吕亚军4,苗㊀壮1(1.河南工业大学土木建筑学院,郑州㊀450001;2.中核港航工程有限公司,广州㊀511458;3.中国核电工程有限公司郑州分公司,郑州㊀450052;4.华北水利水电大学建筑学院,郑州㊀450046)摘要:核技术在造福人类的同时,也产生了无处不在的核辐射,而当前的普通防辐射混凝土并不能完全满足安全防护的需要㊂本文基于最紧密堆积理论,采用不同比例的磁铁矿替换河砂,制备了防辐射超高性能混凝土(UHPC),并对其工作性能㊁力学性能㊁微观结构㊁孔结构,以及γ射线屏蔽性能进行了研究㊂结果表明,磁铁矿的加入使得UHPC 的流动性以及抗压强度略有降低,但降幅较小㊂随着磁铁矿替换比例的增加,UHPC 对γ射线的屏蔽性能明显提高㊂当磁铁矿替换率为100%(体积分数)时,UHPC 的线性衰减系数增大了31.3%,而半值层及十值层均下降了23.8%㊂与此同时,磁铁矿的加入并未改变水化产物的类型,但可改善UHPC 的孔结构,有效降低其孔隙率㊂关键词:磁铁矿;超高性能混凝土;防辐射;γ射线屏蔽;力学性能;工作性能中图分类号:TU528㊀㊀文献标志码:A ㊀㊀文章编号:1001-1625(2021)09-2930-09Preparation and Properties of Ultra-High Performance Concrete for Radiation Protection of MagnetiteHAN Jianjun 1,LIAO Dang 1,XI Zhuangmin 1,TANG Haichao 2,DAI Chongyang 3,LYU Yajun 4,MIAO Zhuang 1(1.School of Civil Architecture,Henan University of Technology,Zhengzhou 450001,China;2.China Nuclear Harbour Engineering Co.,Ltd,Guangzhou 511458,China;3.Zhengzhou Branch,China Nuclear Power Engineering Co.,Ltd.,Zhengzhou 450052,China;4.School of Architecture,North China University of Water Resources and Hydropower,Zhengzhou 450046,China)Abstract :While the nuclear technology benefits mankind,it also produces nuclear radiation everywhere.However,the current ordinary radiation-proof concrete cannot completely meet the needs of safety protection.In this paper,based on the tightest packing theory,the ultra-high performance concrete (UHPC)for radiation protection was prepared by replacing river sand with different proportions of magnetite,and its working performance,mechanical properties,microstructure,pore structure,and γ-ray shielding performance were studied.The results show that the fluidity and compressive strength of UHPC slightly decrease with the addition of magnetite,but the decline is small.As the replacement proportion of magnetite increases,the γ-ray shielding performance of UHPC is improved obviously.When the replacement proportion of magnetite is 100%(volume fraction),the linear attenuation coefficient of UHPC increases by 31.3%,while the half-value layer and ten-value layer all decrease by 23.8%.The addition of magnetite does not change the type of hydration products,but improves the pore structure of UHPC and effectively reduces its porosity.Key words :magnetite;ultra-high performance concrete;radiation protection;γ-ray shielding;mechanical property;working performance 收稿日期:2021-03-19;修订日期:2021-04-18基金项目:国家自然科学基金面上项目(51779096,51979169);河南省高校科技创新团队支持计划(20IRTSTHN010)作者简介:韩建军(1974 ),男,博士,副教授㊂主要从事建筑材料方面的研究㊂E-mail:hanjianjun@通信作者:吕亚军,博士,副教授㊂E-mail:darkdanking@0㊀引㊀言核技术已被广泛应用于医疗[1]㊁核电[2]及农业等领域,在造福人类的同时,其安全性也受到了公众的高㊀第9期韩建军等:磁铁矿防辐射超高性能混凝土制备及性能研究2931度关注㊂核技术在应用过程中会产生核辐射,长时间暴露于核辐射环境中,人们会出现免疫力下降㊁患癌,甚至立即死亡等问题[3],因此对核设备进行有效辐射屏蔽至关重要㊂混凝土由于具有原料丰富㊁成本较低㊁易成型等特点,成为当前应用较为广泛的辐射屏蔽材料㊂防辐射混凝土被广泛应用于核反应堆的安全壳㊁核废料的储存设施,以及军事核设施,对于保护核设施的安全以及屏蔽核辐射发挥着重要作用㊂研究[4]表明,高原子序数和高密度材料具有较好的辐射衰减效果㊂因此,硼铁㊁重晶石㊁花岗岩等高密度材料常作为骨料添加入混凝土中,用于防辐射混凝土的制备和研究㊂当前制备的防辐射混凝土普遍存在防辐射性能良好,但强度较低的问题[5-7]㊂随着核电技术的发展,核反应堆的功率更大,设计寿命更长(如我国研制的 华龙一号 反应堆设计寿命达到60年),这都对核设施的防护以及辐射屏蔽提出了更高的要求㊂因此,制备更高强度的防辐射混凝土具有重要的现实意义㊂超高性能混凝土(ultra-high performance concrete,UHPC)是一种新兴的水泥基复合材料,具有超高强度㊁良好的韧性和耐久性,拥有十分广阔的应用前景[8-10]㊂UHPC的优异性能得益于其最紧密堆积设计理论[11]㊂UHPC良好的级配使其密实度较大,较低的孔隙率使其能够有效抵抗有害介质的侵蚀[12],低水胶比导致其内部存在大量未水化水泥颗粒,使其具有一定的自行修复能力,能够满足各种严苛环境下工程结构的高性能要求[13]㊂国内外学者研究了机制砂㊁铅锌尾矿及礁石粉等替代骨料㊁微粉制备UHPC的相关性能㊂张志豪等[14]研究发现,使用30%(质量分数)以内的礁石粉替代水泥可以提高UHPC的抗压强度㊂赵学涛等[15]研究发现,当使用掺量为10%~20%(质量分数)的机制砂替代河砂时,UHPC的抗压㊁抗折强度有大幅提高㊂Wang等[11]研究发现,采用建筑废料替代体积分数为50%的水泥和19%的细骨料时,所制备的UHPC强度不会明显降低㊂然而,当前对于UHPC辐射屏蔽性能的研究相对匮乏㊂基于此,本文采用防辐射材料替代骨料,制备一种兼具防辐射性能的UHPC,以应对当前核防护设施面临的挑战㊂本文基于最紧密堆积设计理论,根据修正后的Andreasen and Andersen(A&A)模型进行配合比的优化设计㊂采用不同比例(0%㊁20%㊁40%㊁60%㊁80%㊁100%,体积分数,下同)的磁铁矿替代天然河砂,制备防辐射UHPC,并对其工作性能㊁力学性能㊁微观结构㊁孔结构,以及γ射线屏蔽性能进行测试和表征,分析磁铁矿的加入对UHPC性能的影响㊂1㊀实㊀验1.1㊀材㊀料水泥:河南永安水泥有限责任公司生产的P㊃Ⅱ52.5水泥;粉煤灰:荣昌盛环保材料厂生产的一级粉煤灰;硅灰:洛阳裕民微硅粉有限公司生产;砂:选用洗净的粒径范围分别为0~0.60mm㊁0.60~1.18mm的天然河砂;磁铁矿:巩义市家顺净水材料厂生产;减水剂:江苏苏博特新材料股份有限公司生产的聚羧酸高效减水剂,减水率30%,固含量30%;钢纤维:史尉克公司生产的长13mm㊁直径0.22mm的镀铜微钢纤维;水:自来水㊂磁铁矿形态如图1所示,其主要化学成分如表1所示㊂图2为磁铁矿X射线衍射(XRD)谱,分析结果表明,磁铁矿的主要物相包括钛铁矿㊁二氧化钛㊁堇青石㊁镁铁辉石及角闪石㊂图1㊀磁铁矿的数字图像和SEM照片Fig.1㊀Digital image and SEM image of magnetite2932㊀水泥混凝土硅酸盐通报㊀㊀㊀㊀㊀㊀第40卷表1㊀磁铁矿中主要化学成分Table 1㊀Main chemical composition of magnetite Composition Fe 2O 3TiO 2SiO 2Al 2O 3CaO MgOMass fraction /%49.3124.0013.80 5.52 4.15 1.991.2㊀试验方法1.2.1㊀配合比设计为了使制备的防辐射UHPC 发挥优异的性能,根据修正后的A&A 模型对其进行配合比的优化设计㊂首先,根据修正后的A&A 模型确定目标曲线,如公式(1)所示,然后通过调整混凝土中混合物的比例使其组成的粒径分布曲线接近目标曲线,获得最优配合比㊂各混合物的粒径分布㊁目标曲线以及拟合曲线如图3所示㊂P (D )=D q -D q min D q max -D q min (1)式中:D 为颗粒粒径,μm;P (D )为粒径小于D 的颗粒百分含量;D max 为最大粒径,μm;D min 为最小粒径,μm;q为分布模量,取值为0.23㊂图2㊀磁铁矿的XRD 谱Fig.2㊀XRD pattern of magnetite 图3㊀混合物的粒径分布㊁目标曲线以及拟合曲线Fig.3㊀Particle size distribution,target curve and fitting curve of mixtures㊀㊀采用0~0.60mm 和0.60~1.18mm 两种粒径的磁铁矿替换河砂,替换比例为0%㊁20%㊁40%㊁60%㊁80%㊁100%,所得UHPC 配合比见表2㊂表2㊀UHPC 配合比设计Table 2㊀Mix proportion design of UHPCGroupMix proportion /(kg㊃m -3)Silica fume Cement Fly ash River sand 0~0.60mm River sand 0.60~1.18mm Magnetite 0~0.60mm Magnetite 0.60~1.18mm Water Water reducer Steel fiber C01018031817172630020630156C2010180318157421028710520630156C4010180318143015857421020630156C6010180318128710586031620630156C8010180318114353114842120630156C10010180318100143452620630156㊀㊀注:C 表示磁铁矿;0㊁20㊁40㊁60㊁80㊁100分别表示磁铁矿对河砂的替换率为0%㊁20%㊁40%㊁60%㊁80%㊁100%,该替换为体积替换㊂1.2.2㊀流动度测试采用跳桌法,根据‘水泥胶砂流动度测定方法“(GB /T 2419 2005)进行UHPC 拌合物的流动度测试㊂将拌合物分两层装入截锥金属圆模并进行捣压,提起圆模的同时开动跳桌,在完成25次跳动后,用卡尺量取相互垂直方向的两个直径,两者平均值即为所制备UHPC 的流动度㊂㊀第9期韩建军等:磁铁矿防辐射超高性能混凝土制备及性能研究2933 1.2.3㊀抗压强度测试根据‘水泥胶砂强度检验方法(ISO法)“(GB/T17671 1999)进行抗压强度测试㊂所制备试块规格为40mmˑ40mmˑ160mm,待脱模后置于温度(20ʃ1)ħ㊁湿度95%的标准养护箱中养护3d㊁7d和28d,取每组3个试块抗压强度的平均值作为测试值㊂1.2.4㊀微观结构表征使用D8ADVANCE X射线衍射仪(布鲁克公司)对粉末样品(<75μm)进行XRD分析,样品扫描角度范围为5ʎ~70ʎ,样品取自固化28d的C0㊁C20㊁C40㊁C60㊁C80㊁C100组试块㊂采用日立S4800场发射扫描电镜进行UHPC微观形貌分析,加速电压为15kV,测试样品取自固化28d的C100组UHPC试块,测试前先放入50ħ的烘箱中干燥2h㊂1.2.5㊀孔结构测试采用麦克Auto Pore V9600压汞仪,对固化28d的C0㊁C20㊁C40㊁C60㊁C80㊁C100组UHPC试块进行孔结构测试,最大压力为421MPa,接触角为130ʎ㊂1.2.6㊀γ射线屏蔽测试采用γ射线光谱仪(铯-137作为放射源,能量为662keV)对制备的防辐射试块进行γ射线屏蔽性能测试,如图4所示㊂制成截面尺寸为150mmˑ150mm,厚度分别为1cm㊁2cm㊁3cm㊁4cm㊁5cm的试块㊂通过对试块进行叠加,测试不同磁铁矿掺量以及厚度的防辐射试块对于γ射线的屏蔽情况㊂图4㊀防辐射试块及测试装置Fig.4㊀Radiation-proof specimen and test apparatus采用线性衰减系数(μ)㊁质量衰减系数(μm)㊁半值层(H VL)㊁十值层(T VL)及平均自由程(λ)5个指标对所制备防辐射UHPC的γ射线屏蔽性能进行评价㊂其中,μ表示射线在材料中穿过单位距离时被吸收的概率[2],μ越大,防辐射性能越强,其定义如公式(2)所示㊂μm指单位质量厚度的物质对射线的衰减程度,如式(3)所示㊂H VL和T VL表示当γ射线强度减弱至初始值的一半和十分之一时,所穿过的材料厚度,其计算公式分别如式(4)㊁式(5)所示[7]㊂λ表示光子之间连续两次相互作用的平均距离,如式(6)所示㊂μ=1x ln l0l()(2)式中:l0为辐射初始强度;l为辐射透射后强度;x为防辐射材料厚度㊂μm=μρ(3)式中:ρ为试块密度㊂H VL=ln2μ(4)T VL=ln10μ(5)λ=1μ(6)2934㊀水泥混凝土硅酸盐通报㊀㊀㊀㊀㊀㊀第40卷2㊀结果与讨论2.1㊀工作性能磁铁矿掺量对UHPC 拌合物流动度的影响如图5所示㊂结果表明,随着磁铁矿掺量的增加,UHPC 拌合物的流动度呈下降趋势㊂当仅以河砂作为骨料时,UHPC 拌合物的流动度最大,为277.5mm;当磁铁矿替换率为100%时,流动度下降到233.0mm,相较于C0组流动度虽有所降低,但制备的UHPC 拌合物依然保持较好的流动性㊂河砂由于受到河水长期的冲刷,颗粒形状较为规则㊁圆润,颗粒间的摩擦阻力较小,故当只有河砂作为骨料时,UHPC 拌合物的流动性最好㊂而试验所用的磁铁矿由于经过破碎机的挤压㊁破碎,造成其形状不规则,导致颗粒间的摩擦力增大,加之磁铁矿粒径分布相较于河砂整体偏小(由图3可以看出),这就造成骨料的比表面积增大,浆体吸附自由水更多,故UHPC 拌合物的流动性随着磁铁矿掺量的增加而下降㊂图5㊀不同磁铁矿掺量UHPC 的流动度Fig.5㊀Fluidity of UHPC with different magnetitecontent 图6㊀不同磁铁矿掺量UHPC 的抗压强度Fig.6㊀Compressive strength of UHPC with different magnetite content2.2㊀力学性能采用不同掺量磁铁矿替代河砂所制备的UHPC 3d㊁7d 和28d 的抗压强度如图6所示㊂结果表明,UHPC 的抗压强度随着养护龄期的增加而逐渐提高㊂基准组(C0)试块3d㊁7d 和28d 的抗压强度分别为117MPa㊁136MPa 和156MPa,强度的增长表现出早期上升快,后期慢的趋势,这与已有研究[11,14,16-17]相符合㊂与此同时,随着磁铁矿掺量的增加,UHPC 的抗压强度整体呈下降趋势㊂与基准组相比,磁铁矿替换率为20%㊁40%㊁60%㊁80%以及100%的UHPC 试块的28d 抗压强度分别下降了4MPa㊁7MPa㊁5MPa㊁5MPa 以及7MPa,下降幅度较小㊂磁铁矿替换河砂对UHPC 抗压强度影响较小的原因为:一方面,磁铁矿莫氏硬度(5.5~6.5)低于河砂图7㊀不同磁铁矿掺量UHPC 的XRD 分析Fig.7㊀XRD analysis of UHPC with different magnetite content (6.5~7.0),高硬度骨料可以提高混凝土抗压强度[18-19];另一方面,磁铁矿的加入会使UHPC 内部堆积更加密实,密实的堆积结构以及较强的黏结力在一定程度上抵消了磁铁矿骨料自身硬度不足导致的UHPC 抗压强度的下降㊂所以从整体来看,磁铁矿替换河砂,并未对UHPC 的抗压强度产生显著的负面影响㊂2.3㊀微观结构图7显示了不同磁铁矿掺量UHPC 固化28d 的XRD 谱㊂结果表明,UHPC 中主要物相包括钾长石㊁石英㊁钠长石㊁硅酸二钙㊁硅酸三钙㊁钙矾石以及氢氧化钙㊂磁铁矿的加入并未改变水化产物的类型,水㊀第9期韩建军等:磁铁矿防辐射超高性能混凝土制备及性能研究2935化产物为钙矾石和氢氧化钙,衍射峰分别在11ʎ和21ʎ处㊂钙矾石是UHPC强度的重要来源,随着磁铁矿掺量的增加,钙矾石的衍射峰强度并未明显变化,这也是加入磁铁矿后UHPC抗压强度未明显下降的原因㊂与此同时,衍射峰在35ʎ㊁38ʎ㊁40ʎ以及43ʎ处的C2S以及C3S表明UHPC中存在未水化的水泥,这是UHPC水胶比较低造成的㊂图8显示了固化28d的UHPC钢纤维-水泥基界面过渡区的微观形貌㊂从图中可以看出,在钢纤维与水泥浆交接区域,两者结合紧密,说明钢纤维与混凝土之间的黏结性较好,有利于提高UHPC的强度及韧性㊂图8㊀UHPC钢纤维-水泥基界面过渡区的微观形貌Fig.8㊀Micromorphology of UHPC steel fiber-cement based interface transition zone2.4㊀孔结构对固化28d的UHPC试块进行压力范围为0~421MPa的压汞测试,UHPC试块的孔径分布和累积孔体积结果分别如图9㊁图10所示㊂由图9可以看出,各组UHPC试块以孔径20nm以下的无害孔为主㊂由图10可以看出,磁铁矿的加入一定程度上改善了UHPC的孔结构㊂基准组UHPC试块孔径相对较大,但其也以孔径20nm以下的无害孔以及20~100nm的少害孔为主,这可能与河砂的粒径相较于磁铁矿整体偏大有关㊂孔隙率是影响混凝土抗压强度的因素之一[20]㊂整体而言,各组UHPC试块的孔隙率都较低,这也是UHPC保持高强度的重要原因㊂图9㊀UHPC的孔径分布Fig.10㊀Cumulative pore size distribution of UHPC Fig.9㊀Pore size distribution of UHPC图10㊀UHPC的累积孔径分布2.5㊀γ射线屏蔽性能首先,利用最小二乘法对ln(l0/l)与材料厚度(x)所确定的点进行线性拟合,结果如图11所示㊂由公式(2)可知,ln(l0/l)与x的拟合曲线的斜率即μ㊂由图11可知,C0㊁C20㊁C40㊁C60㊁C80㊁C100组UHPC试块的μ值分别为0.1538cm-1㊁0.1667cm-1㊁0.1693cm-1㊁0.1891cm-1㊁0.1917cm-1㊁0.2019cm-1,即线性衰减系数随磁铁矿掺量的增加而增大,其中C100组的线性衰减系数相较于C0组增大了31.3%㊂γ射线屏蔽测试结果如表3所示㊂由表3可知,随着磁铁矿掺量的增加,质量衰减系数(μm)㊁半值层(H VL)㊁十值层(T VL)以及平均自由程(λ)的值均减小,表明UHPC的辐射屏蔽性能增强㊂其中,与C0组相2936㊀水泥混凝土硅酸盐通报㊀㊀㊀㊀㊀㊀第40卷比,C100组试块的H VL 以及T VL 均减少23.8%,μm 和λ分别下降了6.7%和23.8%㊂Khan 等[4]研究表明,高密度以及较高原子序数的材料往往具有更高的辐射屏蔽性能㊂添加磁铁矿的UHPC 之所以辐射屏蔽性能更强,一方面,得益于磁铁矿比河砂具有更高的密度㊂由表3可知,随着磁铁矿掺量的增加,UHPC 试块的密度(ρ)增大,μ增大,H VL 和T VL 逐渐减小㊂另一方面,掺加磁铁矿UHPC 的辐射屏蔽性能与康普顿散射效应有关[21]㊂因磁铁矿中铁㊁钛等较高原子序数的元素含量多,当γ射线进入混凝土时,其光子会和这些元素的核外电子碰撞,削弱γ射线的透射力,进而提升UHPC 的辐射屏蔽性能㊂图11㊀ln(l /l 0)与试块厚度的线性拟合结果Fig.11㊀Linear fitting results of ln(l /l 0)and test block thickness表3㊀γ射线屏蔽测试结果Table 3㊀γ-ray shielding test resultsSource Groupρ/(g㊃cm -3)μ/cm -1μm /(cm 2㊃g -1)H VL /cm T VL /cm λ/cm 137CsC0 2.450.15380.0629 4.50714.971 6.502C20 2.650.16670.0629 4.15813.813 5.999C40 2.850.16930.0594 4.09413.601 5.907C603.040.18910.0620 3.66612.177 5.288C80 3.230.19170.0592 3.61612.011 5.217C100 3.430.20190.0587 3.43311.4054.9532.6㊀与现有防辐射混凝土的比较为了评估本文制备UHPC 的力学性能以及防辐射性能,将本文结果与文献[7,22-24]中的研究数据进行了对比,如图12所示㊂同时,为了保证对比的有效性,选用的文献中均采用能量值662keV 的铯-137作为放射源㊂由图12可知,本文制备的UHPC 的抗压强度在150MPa 左右,略低于Azreen 等[22]制备的UHPC,但远高于其他普通混凝土㊂Azreen 等[22]所制备UHPC 强度高与其超低的水灰比(0.17)有关㊂在防辐射性能方面,本文制备UHPC 的线性衰减系数在0.1538~0.2019cm -1,处于中等水平,且防辐射性能强于Azreen 等[22]所制备的UHPC㊂值得注意的是,密度越大的混凝土往往线性衰减系数越大,具有更好的防辐射性能㊂㊀第9期韩建军等:磁铁矿防辐射超高性能混凝土制备及性能研究2937图12㊀抗压强度㊁线性衰减系数以及密度的关系Fig.12㊀Relationship between compressive strength,linear attenuation coefficient and density3㊀结㊀论(1)随着磁铁矿替换河砂比例的增加,UHPC拌合物的流动度逐渐减小㊂当磁铁矿完全替换河砂时, 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门类知识：Steel door 钢质门Crack paint series 裂纹油漆门Embossing door 浮雕板门Electrolysis board 电解板门Imitate copper door仿铜门Solid wood compound door 实木复合门High class craft door 工艺木门PVC free coating door PVC 免漆门High polymer free coating door 高分子免漆门Interior steel- wooden door室内钢木门HDF molded door 模压门Stainless door 不锈钢门Aluminum alloy door 铝合金门Plastic steel door 塑钢门Bolt 螺栓Reinforced side locking point 加固侧端锁点Door viewer 猫眼Thickened door leaf 加厚门扇Main lock 主锁Door leaf 门扇Magnetic seal 门吸Doorframe 门框new-style reinforced hinge 新款加固合页Luminous stealth doorbell 夜光隐藏门铃Gas-bag magnetic seal 磁性密封条Surface processing effect 表面处理效果Stainless steel doorsill 不锈钢门挡Bolt 螺栓super-thick door leaf triple anti- theft bolt 超厚门扇三重防盗螺栓Machine lock 机械锁Pull 拉手Door sill 门挡Single color 单色Width 宽height 高long 长thickness 厚度Door formula line 门套线Combined door formula big panel 门框Door ward bar 门档条Wooden screw 木质螺丝Sheet iron 铁板Batten 板条Natural stuffing 自然填充物Steel plate 铁板Powder coated 喷塑Phosphate 磷化Anti-ultraviolet 防紫外线Rock wool 石棉窗户：UPVC windows UPVC窗户Aluminum window 铝合金窗户Window blinds 百叶窗Steel window 铁窗Parapet wall 护栏Top hung fanlight 顶悬气窗Moulding 装饰线条Top rail 上横档Locking handle 把手Friction hinge 摩擦教练Jamb 侧柱Transom 横梁Cill 窗台Mullion 树框Stay 支撑杆Bottom rail 下横档Vertical sliding 垂直滑动Triple track 三轨道校具产品知识：School desk 学校桌子Fitting 配件Apartment bed 学校公寓床Dining table 餐桌Laboratory 实验室家具Blackboard 黑板Library furniture 图书馆家具Platoon chair 体育馆排椅Child school desk 儿童桌子Particle board/flake board/Chipboard 刨花板Plywood 多层板/胶合板MDF 密度板Melamine 三聚氰胺Fireproofing board, high pressure laminate board (HPL Board) 防火板Edge banding strip 封边Grain 纹理Formaldehyde Emission 甲醛释放量Moulded board 模压板Fiber glass/fiber reinforced plastics 玻璃钢Chemical-Resistant Laminate 理化板Round Steel/steel rod 钢筋Steel circle tube 钢管square tube 方管Rectangle tube 矩形管Flat steel bar 扁铁Angle iron 角钢Surface electrostatic powder spraying/powder coatings 喷塑办公家具：Boss table 班台Book counter 文件柜Computer table 电脑桌Sofa 沙发民用家具：Bedroom furniture 卧室家具Studio furniture 书房家具Child combination 儿童组合Closet 衣柜Television cabinet 电视柜Shoes cabinet 鞋柜Kitchen furniture 厨房家具Leisure furniture 户外家具Trash can 垃圾桶Healthy boby equipment 健身器材Goods frame 货架Ladder 梯子产品专业术语窗户专业术语：窗METAL WINDOWS & FRAMES金属窗metal windows钢窗steel windows铝窗aluminum windows不锈钢窗stainless steel windows木窗wood windows塑料窗vinyl windows特种窗special windows室外上卷式百叶窗exterior roll-up windows shutters天窗及屋顶采光SKYLIGHTS屋顶窗roof windows五金配件HARDW ARE窗五金window hardware & specialties门窗配件door and window accessories玻璃及相关制品GLAZING玻璃glass推拉窗：Sliding Window 节省空间，经济、适用：Save space, economic, and practical适合家庭、办公隔断、酒店等场所：Suitable for home, office partitions, hotels and other establishmentsSave space适合家庭、宾馆、酒店等场所：Suitable for families, hotels, places such as hotels圆弧窗:Arc Window弧形设计，满足了不同建筑的结构：Arc Design，To meet different building structures 适合住宅、公寓、别墅等：Suitable for residential, apartment, villa, etc平开上悬窗top-hung window压条：glazing bead窗框：all kinds of frames 推拉扇：push pull door leaf 铝合金窗：aluminum alloy window铝合金窗纱：aluminum alloy wire netting铝合金窗轨：al-alloy curtain rod铝合金窗扇：aluminum alloy sash铝门窗料：aluminum window door and sections铝门窗锁：lock for aluminum door and window辅助配件:Auxiliary accessories坚固、高档、美观：Rugged, high-grade and beautiful且具有隔热、保湿功能：And has heat insulation, heat preservation function适合家庭、单位、酒店等场所：Suitable for families, units, places such as hotels内倒内开，双重功能，节省空间：Within the open within the inverted, double feature，钢质门专业术语：钢质门: Steel door仿铜门: Imitate copper door冷轧钢板: Cold-rolled steel sheet：蜂窝纸: Honeycomb material :防火棉: Fireproof mountain cork防火石膏: Fireproof gypsum气窗：Transom门头：Door header门柱：Door pillar单门：Single door双开门：Ddouble door子母门：Son-mother door子门：Secondary door母门：Primary door门扇:Door leaf门框:Door frame螺栓: Bolt侧锁点:Side locking point猫眼:Door viewer主锁:Main lock密封条:Magnetic seal铰链/合页: Hinge门铃:Door bell门下档:Doorsill拉手:Handle磷化:Phosphate喷塑:Powder coating热转印:Heat transfer printing金属漆:Metallic paint:仿铜漆:Imitation copper paint校具专业术语：学校桌子School desk配件Fitting学校公寓床Apartment bed餐桌Dining table实验室家具Laboratory黑板Blackboard图书馆家具Library furniture体育馆排椅Platoon chair儿童桌Child school desk子刨花板Particle board/flake board/Chipboard 多层板/胶合板Plywood密度板MDF三聚氰胺Melamine防火板Fireproofing board, high pressure laminate board (HPL Board)封边Edge banding strip纹理Grain甲醛释放量Formaldehyde Emission模压板Moulded board玻璃钢Fiber glass/fiber reinforced plastics 理化板Chemical-Resistant Laminate 钢筋Round Steel/steel rod钢管Steel circle tube方管square tube矩形管Rectangle tube扁铁Flat steel bar角钢Angle iron喷塑Surface electrostatic powder spraying/powder coatings高质量不褪色 A high degree of light-fastness机械磨蚀Abrasion磨损硬度Abrasion hardness砂带Abrasive band网兜Basket shelf钢木室内门Interior steel-wood door强化木门（三聚氰胺木门）Melamine wood door实木复合油漆门/烤漆门Solid wood compound doorPVC免漆室内门PVC door模压门HDF molded door塑钢门UPVC door三聚氰胺层压：melamine lamination蜂窝纸：honeycomb material实木框架：solid wood frame门套板: Combined door formula big panel门套线: Door formula line门挡条: Door ward part墙体：Wall thicknessAAbram's rule阿勃拉姆规则Abrasion磨耗Accelerated strength testing快速强度试验Acid resistance耐酸性Adiabatic temperature rise绝热升温Admixture外加剂Aggregate集料（混凝土）Air entrainment引气（加气）Autoclave高压釜Accelerated curing快速养护Absorbed water吸附水Added water附加水Aggregate bulk density集料松散容重Auti-corrosion Admixture防锈剂Anisotropic materials各向异性材料Air-entrained concrete引气混凝土Air Entrain Admixture引气剂Aggregate porosity集料孔隙率Artificial marble人造大理石Alite阿利特Alkali-aggregate reaction碱－集料反应Alkalies in Portland cement波特兰水泥中的碱Alkali-silica reaction碱－二氧化硅反应Anhydrite无水石膏（硬石膏）Autoclave expansion test高压釜膨胀试验Air-entrained concrete加气混凝土Adhesion agent粘着剂Accelerating agent速凝剂All mesh ferrocement无筋钢丝网水泥Allyl-Butadiene-Styrene丙烯氰－丁二烯－苯乙烯共聚树脂（ABS）Air pockets鼓泡Axial tensive property轴心受拉性能Axial compressive property轴心受压性能Air impermeability气密性Abnormal Polypropylene无规聚丙烯（APP）Asbestos fibres石棉纤维Asbestos insulation石棉绝热制品Autoclave expansion test压蒸法Artificial人造石Air entraining and water-reducing admixture 引气减水剂Active addition活性混合材Addition of cement水泥混合材Aluminoferic cement clinker铁铝酸盐水泥熟料Age龄期，时期Aluminum silicate wool硅酸铝棉Aluminum foil铝箔Air space insulation封闭空气间层Areal thermal resistance（specific thermal resistance）比热阻（热导率的倒数）Absorptivity吸收率Air permeability（Air penetration coefficient）空气渗透率BBrick 绝热砖Bleeding 泌水Bitumen-determination of penetration 沥青针入度测定法Battery-mold process 成组立模工艺Bar spacing 加筋间距Binder bonding agent 粘合剂Barytes 重晶石Batchhing 称量（配料）Biaxial behavior 双轴向性质Blaine fineness 勃来恩，细度Blast-furnace slag 高炉矿渣Blast-furnace slag cements 高炉矿渣水泥Blended portland cements 掺混合料的波特兰水泥Bogue equations 鲍格方程式Bond 粘结Brucite 氢氧镁石（水镁石）Bulking of sand 砂的湿胀Bull-float 刮尺Board（block）insulation 绝热板Bitumastic paint 沥青涂料Bituminous road materials 沥青筑路材料Blowing agent 发泡剂Bar between mesh 加筋Ball impact test （******强度）落球试验法Basic constituent 碱性组分基本成分Basicity 碱度，碱性Batch mixture 配合料Bend stress 弯曲应力Bituminous paint 沥青涂料Bituminous concrete 沥青混凝土Block brick 大型砌块Blunger 搅拌器，打浆机Brick setting 砖砌体(brickwork)Brittle point of asphalt 沥青冷脆点Broken stone 碎石Bubbing potential 发泡能力Building brick 建筑红砖Building system 建筑体系，建筑系统Brittle material 脆性材料CCalcium aluminate cement 铝酸钙水泥Calcium aluminates 铝酸钙Calcium chloride 氯化钙Calcium ferroaluminates 铁铅酸钙Calcium hydroxide 氢氧化钙Calcium oxide 氧化钙Calcium silicate hydrate 水化硅酸钙Calcium silicate 硅酸钙Calcium sulfates 硫酸钙Calcium sulfoaluminate 硫铅酸钙Calcium sulfoaluminate hydrates 水化硫铝酸钙Capillary voids（pores）in cement 水泥中的毛细管Capillary water 毛细管水Carbon dioxide 二氧化碳Cavitation 混凝土中的大孔洞，空蚀作用Cement fineness 水泥细度Cement paste 水泥浆Cement soundness 水泥安定性Cement specifications 水泥规范Cement strength 水泥强度Cement types 水泥品种Ceramsite 陶粒Chalcedony 玉髓Chemically combined water 化学结合水Chert 燧石（黑硅石）Chloride 氯化物Chloroprene Rubber 氯丁橡胶（CR）Chord modulus 弦弹性模量Clinker 熟料Coarse aggregate 粗集料Cold-weather concreting 冷天浇筑混凝土Compacting factor test 捣实系数试验Compaction（consolidation）捣实（捣固）Compressive strength 抗压强度Computer control system 计算机控制系统Concrete batching plant 混凝土搅拌站Concrete composition 混凝土配合比Concrete products 混凝土制品Concrete pump 混凝土输送泵Coefficient of permeability of concrete 混凝土渗透系数Carbonated lime sand brick 碳化灰砂砖Carbonating 碳化处理Cement resistance to chemical水泥抗化学侵蚀性Cube size 立方体试件尺寸Characteristic strength 特征强度Coarse aggregate ratio to fine粗集料玉细集料之比Carbonated shrinkage 碳化收缩Calcium silicate insulation 硅酸钙绝热制品Cellular（foamed）glass 泡沫玻璃（多孔玻璃）Composite insulation 复合绝热层Cold rolled steel 冷轧钢Cellular concrete 多孔混凝土Complex accelerator based on triethanolamine 三乙醇胺复合早强剂Component 组分，成分，构件Compliance 柔度Composite 复合，合成，复合材料Composite insulation 复合绝热层Composite portland cement 复合硅酸盐水泥Concrete 混凝土Condensed silica fume 浓缩（凝聚）的二氧化硅烟雾（硅粉）Consistency 绸度Core tests 钻芯试验Corrosion of steel in concrete 混凝土中钢筋的腐蚀Cost of concrete 混凝土成本Cracking 开裂Creep 徐变Critical aggregate size 临界集料尺寸C-S-H 水化硅酸钙Coefficient of thermal expansion 热膨胀系数Conductivity 导热性Coefficient of shrinkage 收缩系数Coefficient of permeability of concrete 混凝土收缩系数Cement mortar 水泥胶砂Crescent ribbed bars 月牙肋钢筋Concrete block 混凝土砌块Cold-drawn reinforcement bar 冷拉钢筋Cold rolled steel 冷轧钢Condensation polymerization 缩聚反应Critical degree of saturation 临界饱和度Critical stress 临界压力Cryogenic behavior 低温性质Crystallization pressure of salts盐的结晶压力Crystal structure and reactivity结晶结构和活性Curing 养护Civil Engineering 土木工程Cement 水泥Crack 裂缝Calcium silicate insulation 硅酸钙绝热制品Cement mortar 水泥砂浆Cork 软木Cork insulation 软木绝热制品Cellular（foamed）plastics泡沫塑料（多孔塑料）Cellular（foamed）polystyrene聚苯乙烯泡沫塑料Cellular（foamed）polyurethane聚氨脂泡沫塑料Calcium-resin insulating board 钙塑绝热板Cellular（foamed）rubber 泡沫橡胶DDarby 刮尺D-cracking D行裂缝Deicing salts action 除冰盐作用Diatomaceous earth 硅藻土质泥土Dicalcium silicate（C2S）硅酸二钙Dynamic modulus of elasticity 动弹性模量Dolomite 白云石Drying shrinkage 干燥收缩（干缩）Ductility 延性Durability 耐久性Durability factor 耐久性因素Decoration glass 装饰玻璃Decoration mortar 装饰砂浆Deformed bar 变形钢筋，螺纹钢Defoamer 消泡剂Dense concrete 密实混凝土Diatomaceous silicate 硅藻土(Kieselguhr，diatomite)Diatomite insulation 硅藻土绝热制品Density 密度Deformation 变形钢筋Degree of hardness 硬度Degree of humidity 湿度EEarly-age behavior早期性质Ecological benefit生态效应Effective absorption有效吸收Efflorescence白霜Elastic modulus弹性模量Electron micrographs电子显微图Energy requirement能量需要Entrained air引入的空气Extensibility可伸长性Emerging wire露丝Emerging mesh露网Expanded perlite膨胀珍珠岩Epoxy Resin环氧树脂Erosion冲刷风化、剥蚀Ettringite钙矾石Expanded clay and shale膨胀粘土和页岩Expanded slag aggregate膨胀矿渣集料Expansive cement concrete膨胀水泥混凝土Expansive cement膨胀水泥Expansive phenomena in concrete混凝土中的膨胀现象Expanded vermiculite膨胀蛭石Expanded rermiculite insulation膨胀蛭石制品Expanded plastics多孔塑料Engineering plastics工程塑料FFabriform土工模袋False set假凝Feldspar长石Fiber-reinforced concrete纤维增强混凝土Final set终凝Fine aggregate细集料Fineness modulus细度模量Flowing concrete流动混凝土Fly ash粉煤灰Foamed slag泡沫矿渣Formwork removal拆模Ferromanganese锰钢Flow of cement mortar水泥胶砂流动度Fiber reinforced plastics纤维增强塑料Fiber-glass reinforced plastics玻璃纤维增强塑料Facebrick饰面砖，面砖Facing tile外墙面砖Faience mosaic嵌花地砖，釉陶锦砖Fiber cement纤维水泥Figured glass压花玻璃Fine sand细砂Fineness of cement水泥细度Finishing抹面（修整）Flash set闪凝（瞬间凝结）Flexural strength弯曲强度Flint燧石Floating刮平Fracture toughness断裂韧性Free calcium oxide游离氧化钙Freeze-thaw resistance抗冻融性Fresh concrete新拌混凝土Facing面层Fiber insulation纤维绝热材料Flexible insulation柔性绝热制品Frost action on aggregate骨料受到冰冻作用Frost action on cement paste水泥浆受到冰冻作用Future of concrete混凝土的前景Fire resistance耐火性Ferrocement钢丝网水泥Ferrocement with skeletal bar加筋钢丝网水泥Flexural property受弯性能Fatigue resistance耐疲劳性Forst resistance抗冻性Fineness modulus细度模数（M）Flexural rigidity抗弯刚度（B）Foamed concrete泡沫混凝土Fiber board纤维板Frost action on concrete混凝土受到冰冻作用GGamma raysγ-射线Gel pores凝胶孔Gel/space ratio凝胶/空隙比（对强度的影响）(Effect on strength）Geonet土工网Geotextile土工格栅Geotextile木织物Glass geogrid土工复合排水材Geomat土工垫Gradation级配Gypsum石膏Granulated wood粒状棉Glass geogrid玻纤网Glassfiber Reinforced Plastics玻璃纤维增强塑料Glass wool玻璃棉Granular（powder）insulation颗粒绝热材料Gap-graded aggregate间断级配材料Gas concrete加气混凝土Glass玻璃体Giving a basic reaction发生碱性反应Giving an acid reaction发生酸性反应Grading颗粒级配Grain-size refinement级配曲线Gravel砾石、卵石Graywacke杂砂岩Grout薄浆（灌浆）Granite花岗岩Graph图表、图解Green concrete新拌混凝土Gritly粗砂状的Ground slag矿渣粉Gypsum wall board石膏墙板Gypsum concrete石膏混凝土HHardening 硬化Hcp 水化水泥浆的简写Heat of hydration 水化热Heavyweight aggregate 重集料Heavyweight concrete 重混凝土Hemihydrate 半水化物High-alumina cement 高铝水泥High-early strength cement 高早强水泥High-strength concrete 高强混凝土High-workability concrete 高工作性混凝土Hot-weather concreting 热天浇筑混凝土Hydrophilic and hydrophobic 亲水与憎水Hydrated（portland）cement paste 已水化的水泥浆Hydration of portland cement 波特兰水泥的水化Hydration reaction of aluminates 铝酸盐的水化Hydration reaction of silicates 硅酸盐的水化反应Hydraulic cement 水硬性水泥Hydraulic pressure 水压力Honeycomb 蜂窝Heat transfer rate 热流量Homogeneous materials 均质材料High-tensile reinforcing steel 高强度钢筋High-tensile wire 高强钢丝High carbon steel 高碳钢High strength concrete 高强混凝土High performance concrete 高性能混凝土IIgneous rocks for aggregate 作为集料的岩浆岩Impact strength 冲击强度Impregnation with polymers 用聚合物浸渍Initial set 初凝Initial tangent modulus 初始正切模量Interlayer space in C-S-H C-S-H中的层间空间Interlayer water in C-S-H C-S-H中的层间水Iron blast-furnace slag 化铁高炉渣Iron ores aggregate（heavyweight）铁矿石（重集料）Isotropic materials各向同性材料Iron wire低碳钢丝Impact ductility 冲击韧性Impact strength 抗******强度Impermeability 抗渗性，不渗透性Impermeability to water 抗渗水性，不透水性Impregnate 浸渍，渗透Index of quality 品质指标，质量控制标准Inhomogeneous 不均匀的，多相的Initial shrinkage 早期收缩Initial strength 早期强度Insulating layer 隔热层Intarsia 玻璃锦砖Impact resistance 抗******性JJet set cement 喷射水泥Jolting table 振动台Job mix 现场配合Jaw crusher 颚式破碎机"Jian-1" water reducer 减水剂KKilled steel 镇静钢Kiln dust 窑灰，飞灰Kiln building 窑房Kiln plant 窑设备Kilogram calorie 千卡，大卡Knot 木节Kominuter 球磨LLow PH value cement 低碱水泥Laitance 浆皮Leaching of cement paste 水泥浆渗漏Lime cement 石灰水泥Limestone 石灰石Lightweight aggregates 轻集料Lightweight concrete 轻混凝土Lignosulfonate 木质磺酸盐Low heat Portland cement 低热波特兰水泥Laboratory 实验室Lean concrete 贫混凝土Loss of slump of concrete 混凝土的坍落度损失Le chatelier soundness test 雷氏夹法Loss on ignition 烧失量Light weight ferrocement 轻质钢丝网水泥Longitudinal bar 纵筋Longitudinal bar spacing 纵筋间距Loose fill insulation 松散填充绝热层Low alloy steel 低合金钢Low caron colddrawn steel 冷拔低碳钢丝Longitudinal rib 纵肋Lumber grading 木材等级MMacrostructure 宏观结构Magnesium oxide 氧化镁Magnesiun salts solution effect on concrete 镁盐溶液对混凝土的影响Map cracking 地图形裂纹Marcasite 白铁矿Mass concrete 大体积混凝土Maturity concept 成熟度概念Maturity meters 成熟度测定仪Microcracking 微裂缝Microsilica 微细二氧化硅（硅粉）Minimum crack spacing 最小裂缝间距Microcrack 微裂Modulus of deformation 变形模量（EB）Mineral wool insulation 矿棉绝热制品Mineral fibres 矿棉纤维Masonry cement 砌筑水泥Mild steel 低碳钢Medium carbon steel 中碳钢Moisture content of wood 木材含水量Moisture 湿度水分Moisture condition 含水状态Mocromolecule high polymer 高分子Microstructure 微观结构Mixing of concrete 矿物外加剂Mixing water 拌合用水Mix proportioning（designing）配合比（设计）Mix proportions 配合比Modified portland cement 改性的波特兰水泥Modulus of elasticity 弹性模量Modulus of rupture 挠折模量（破裂模量）Monosulfate hydrate 单硫酸盐水化物Mortar 砂浆Multiaxial strength 多轴向强度Mumicipal-waste aggregate 城市废物集料Moisture absorption 吸湿率（water vapour absorption）Moisture content of aggregate 骨料含水量Matrix 基材Mesh-bar placement and tying 铺网扎筋Manual plastering 手工抹浆Maximum size of sand 砂的最大粒径Mortar consistency 砂浆绸度Mortar strength 砂浆强度Maximum crack width 最大裂缝宽度Mix proportion by absolute volume 绝对体积配合比（设计）Mix proportion by loose volume 现场松散体积配合比（设计）Mixed-in-place 现场拌和Mix proportion by weight 重量配合比Mixed process 混合过程Mixing time 拌和时间Mixing water 拌和水Modility 流动性Membreane curing 薄膜养护Map cracking 龟裂Mastic 玛脂Modulus of elasticity concrete 混凝土弹性模量Modulus of water-glass 水玻璃模数Masonry mortar 砌筑砂浆Maximum aggregate size 最大集料粒径Marber 大理岩Moderate heat portland cement 中热硅酸盐水泥Moderate heat of hydration 中热Moderate sulfate resistance 中抗硫酸盐Magnitude of self-stress 自应力NNDT 非破损试验的缩写Neutron radiation 中子辐射Neoprene 氯丁橡胶NNO water reducer NNO型减水剂Non-hydranlic cement 气硬性水泥Non-destructive tests 非破损试验Nuclear shielding concrete 核屏蔽混凝土Normal distribution 正太分布Non-evaporable water 非蒸发水Nominal diameter 公称直径Normal consistency of cement paste 水泥净浆标准绸度Neat cement paste 水泥净浆Needle crystal 针状晶体Needle penetrometer 维OOscillating screen 振动筛Oscillation generator 振动器Oscillator 振动器Oil-well platform concrete 油井平台混凝土Opal 蛋白石Overlays of concrete 混凝土覆盖层Oriented water 定向的水Osmotic pressure 渗透压力Oven-dry aggregate 炉干骨料Overall thermal conductance 总导热系数Organosilicon 有机硅Organosilicon resin 有机硅树脂Oscillate 振动，振荡Ordinary low-alloy steel 普通低合金钢Ordinary oil well cement 普通油井水泥Ordinary portland cement 普通硅酸盐水泥PParticle size 颗粒尺寸Penetration resistance 抗贯入性Periclase 方镁石Perlite 珍珠岩Permeability 渗透性Phosphate 磷酸盐Phenolic Formaldehyde 酚醛树脂（PF）Placing of concrete 混凝土的浇筑Plaster of paris 建筑石膏Polypropylene 聚丙烯（PP）Polystyrene 聚苯乙烯（PS）Polystyrene-plywood laminate 聚苯乙烯胶合木板Polyester plastics 聚酯塑料Plastic veneer 塑料贴面板Plastic-steel window 塑钢窗Polyester 聚酯Polyester Resin 聚酯树脂（PR）Plastic shrinkage 塑性收缩Poisson's ratio 泊松比Polymer concrete 聚合物混凝土（PC）Polymer-impregnated concrete 聚合物浸渍混凝土（PIC）Polymer-cement concrete 聚合物水泥混凝土（PCC）Polymethylmethacrylate 聚甲基丙烯酸甲酯（PMMA）Pore-size distrbution 孔径分布Pore-size refinement 孔径尺寸修整Prestressded ferrocement 预应力钢丝网水泥Plain round bar 光圆钢筋Prestressed steel 预应力钢筋Pumped concrete 泵送混凝土Pumice concrete concrete block 浮石混凝土砌块Plastics 塑料Polythene 聚乙烯（PE）Polyvinyl Alcohol 聚乙烯醇（PV A）Polyvinyl Acetate 聚醋酸乙烯（PV AC）Polyvinyl Chloride 聚氯乙烯（PVC）Polyvinyl Formal 聚乙烯醇缩甲醛（PVFO）Porosity 孔隙率Portland cement 波特兰水泥Portland blast-furnace slag cement 高炉矿渣波特兰水泥Portlandite 氢氧钙石Portland pozzolan cement 火山灰质波特兰水泥Potential compound composition 潜在化合物成分Pyrite pyrrhotite 硫化铁，黄铁矿Particle size distribution 粒度分布Pat test 试饼法PH-value PH值Pozzolan 火山灰Pozzolanic reaction 火山灰质反应Preplaced aggregate concrete 预填集料混凝土Proportioning 配合Pulverized fuel ash 磨细粉煤灰Pull-out test 拔出试验Pumice 浮石QQuality assurance 质量保证Quick set 快凝Quality 质量Quality control 质量控制Quartz glass 石英玻璃Quartz glass fiber 石英玻璃纤维Quartz sand 石英砂Quick lime 生石灰[CaO]Quartz 石英Quatzite 石英岩Quick-taking cement 快凝水泥Quick hardening 水硬性水泥Quench 水淬，骤冷RRadiation shielding concrete辐射屏蔽混凝土Rapid setting and hardening cement快凝与快硬水泥Revibration重新振捣Rice husk ash谷糠灰Ready-mixed concrete预拌混凝土Recycled-concrete aggregate再生混凝土集料Regulated-set cement调凝水泥Retarding admixtures缓凝外加剂Retempering重新调拌Roller-compacted concrete滚筒-压实混凝土Reinforced plastics加筋塑料Reinforcement mat钢筋网Resistance to chemical attack of mortar砂浆耐蚀性Rock wool岩石棉Rigid insulation刚性绝热制品Rib height肋高Rib spacing肋间距Ribbed bars带肋钢筋Rich concrete富混凝土Residue on sieve筋余Raw limestone石灰石Raw gypsum二水石膏SSalt crystallization pressure 盐的结晶压力Sand 砂Sandstone 砂岩Saturated surface dry condition 饱和面干条件Scaling 起皮，鳞片状剥落Schmidt rebound hammer 希密特回弹仪Screeding 抹平Seawater 海水Secant elastic modulus 正割弹性模量Sedimentary rocks for aggregate 作为集料的沉积岩Segregation 离析Self-stressing cement 自应力水泥Setting of cement paste 水泥浆的凝结Special hydraulic cement 特种水硬性水泥Specifications 规范Specific heat 比热Specific surface area 比表面积Sphericity 圆度Splitting ******* strength 劈裂抗拉强度Standard specifications 标准规范Standard test method 标准试验方法Stiffening of cement paste 水泥浆的变硬Strain 应变Strength 强度Setting of concrete 混凝土的凝结Shear-bond failure 剪切粘结破坏Shear strength 剪切强度Shotcreting 喷射混凝土浇筑Shrinkage 收缩Shrinkage-compensating concrete 收缩补偿混凝土Sieve analysis of aggregate 集料的筛分析Silica fume 硅粉Slag 矿渣Slip-formed concrete 滑模混凝土Slump cone test 坍落度锥体试验Slump loss in concrete 混凝土中坍落度损失Solid/space ratio 固体∕空隙比Solid-state hydration 固态水化Soundness 安定性Spacing-factors of entrained air 引入空气的间距因素Structural lightweight concrete 结构轻混凝土Structure（microstructure）of concrete 混凝土的（微观）结构Structures（concrete）in photographs 混凝土结构照片Sulfate attack 硫酸盐侵蚀Sulfate resisting cement 抗硫酸盐水泥Sulfates in portland cement 波特兰水泥中的硫酸盐Sulfides and sulfate aggregate 硫化物与硫酸盐集料Standard sand 标准砂Strength of cement mortar 水泥胶砂强度Strength grade of cement 水泥强度等级Spiral reinforcement 螺纹钢筋Stirrup 箍筋Struture lightweight concrete 结构用轻混凝土Specimen 试件Self-stressing concrete 自应力混凝土Sand grading 砂的级配Sand grading curve 砂的级配曲线Sand grading standard region 砂的级配标准区Self-stressing ferrocement 自应力钢丝网水泥Self-stressing cement mortar 自应力水泥砂浆Shear steel 剪切钢筋Saturation capacity 饱和含水量Saturation point 饱和点Stearic acid 硬脂酸Surface-active agents 表面活性剂Synthetic resin binder 树脂粘结剂Synthetic lightweight aggregate 人造轻集料Shotereting process 喷浆工艺Scaling 麻面Surface dusting 表面起砂Sandwich 夹层Shrinkage crack 收缩裂缝Stressed crack 受力裂缝Special steel 特种钢Sawdust concrete 锯屑混凝土Softening point test 软化点试验Solidification 凝固作用Stress 应力Stress intensity factor 应力强度因素Stress-strain curve 应力－应变曲线Surface moisture 表面水Splitting strength 劈裂强度Splitting failure 劈裂破坏Standard error 标准误差Stand sieve 标准筛Static modulus 静弹性模量Steam curing 蒸汽养护Strength grading 强度级别Strength of cube 立方体强度Strength at 28 days 28天强度Stress concentration 应力集中Styrene Butadiene Rubber 丁苯橡胶（SBR）Styrene-Butadiene-Styrene 苯－丁－苯乙烯Sulphoaluminate cement clinker硫铝酸盐熟料Surface energy 表面能Surface hardness 表面强度Surface ******* 表面张力Sand-lime brick 灰砂砖Saturated aggregate 饱和水集料Superplasticized admixture 超塑化外加剂Surface area 表面积Strength of aggregate 集料强度Strength of cylinders 圆柱体强度Supersulphated cement 石膏矿渣水泥Setting time of concrete 混凝土的凝结时间Standard of concrete 混凝土强度Standard deviation 标准差Structure high density concrete 结构高表观密度混凝土Steel-fibre concrete 钢纤维混凝土Set retarder admixture 缓凝剂Set retarding and water-reducing admixture 缓凝减水剂Superplasticizer admixture 高效减水剂Superplasticized concrete 超塑性混凝土Setting time 凝结时间Sulphonated formaldehyde melamine 磺化甲醛三聚氰胺Saturated and surface-dry aggregate 饱和面干集料T Tangent modulus of elasticity 正切弹性模量Temperature effects 温度效应Tensile strain 拉伸应变Tensile strain capacity 拉伸应变能力Tensile strength 拉伸强度（抗拉强度）Test methods 试验方法Thermal conductivity 导热性Thermal expansion coefficient 热膨胀系数Thermal shrinkage 热收缩Truckmixing 卡车搅拌Total water/cement ratio 总水灰比Trial mixes 试拌合物The particle grading 颗粒级配Tough aggregate 韧性集料Timber 木材Thermal insulation material 保温材料Test sieve 试验筛Through-solution hydration 通过溶液的水化Time of set 凝结时间Tobermorite gel 莫来石凝胶Topochemical hydration 局部水化Toughness 韧性Transition zone 过渡区Transporting concrete 混凝土输送Tricalcium aluminate 铝酸三钙Tricalcium silicate 硅酸三钙Triethanolamine 三乙醇胺Testing of material 材料试验Testing sieve shaker 试验用振动筛分机Test load 试验负荷Test method 试验仪表Test report 试验报告Test result 试验结果Tetracalcium aluminate hydrate 水化铝酸四钙Texture of wood 木材纹理Theories of cement setting and hardening 水泥凝结硬化理论Thermal contraction 热收缩Thermal diffusivity 热扩散性Thermosetting plastics 热固性塑料Technical manual 技术规范Test method of ferrocement panels in flexure 钢丝网水泥板受弯试验方法Transverse barspacing 横筋间距Thermo plastics 热塑性塑料Transverse rib 横肋Transverse bar 横筋Temperature shrinkage 温度收缩Thermal insulation material 绝热材料Thermal insulation properties 保温性能Thermal insulating concrete 绝热混凝土Thermal insulating plaster（Thermal insulating mortar）绝热砂浆UUltrasonic pulse velocity 超声脉冲速度Unixial compression behavior 单轴向受压状况Ultimate creep 极限徐变Ultimate strain 极限应变Unlimited swelling gel 无限膨胀凝胶Units of measurement 计量单位Unit weight 单位重量Ultimate gation 极限伸长值Ultimate principles 基本原理Ultrasonic inspection 超声波样份Uncombined CaO 游离CaOVVander Wale force 范德华力Vebe test 维勃试验Vermiculite 蛭石Very high early strength cement 超高早强水泥Vibration 振动，振捣Vicat apparatus 维卡仪V oid in hydrated cement paste 水化水泥浆中的孔隙V olcanic glass 火山玻璃Vinsol resin 松香皂树脂Vapor pressure 蒸汽压力Variegated glass 大理石纹Veneer 墙面砖、饰面砖Vesicular structure 多孔结构Vicat needle 维卡仪Viscometer 粘度仪Viscosity 粘度粘滞性Viscosity of asphalt 沥青粘滞性Voids ratio 孔隙率Vibro-moulding process 振动成型工艺Vibrating stamping process 震动模压工艺Vibrating vacuum-dewater process 振动-真空脱水工艺Vacuum insulation 真空绝热Vapour barrier，water vapour retarder 隔汽层Vibrating table 振动台V oids detection 空隙的测定V-B test（vebe test）维勃证WWater 水Water/cement ratio 水灰比Water-reducing admixture 减水剂Water tightness 水密性、不透水性Water content 用水量Water requirement 需水量Water-lightness 透水性Water-reducing retaders 缓凝减水剂White cement 白水泥Windsor probe 温莎探针Winter concreting 混凝土冬季浇筑Workability 工作性（工作度）Wetting agents 温润剂Water solubility 水溶性Water retentivity 保水性Water storage 在水中养护Water repellent 疏水的、不吸水的、憎水的Water resistance 抗水性Water vapor 水蒸汽Wearability 耐磨性Weather resistance 耐候性Workability 可加工性Wood-preserving process 木材防腐处理Work done by impact ******功Weighting error 称量误差Workability loss of with time 和易性随时间损失Workability of ready-mixed concrete 预拌混凝土和易性Workability of light-weight concrete 轻混凝土和易性Water-reducing admixture 普通减水剂Water-proofing 防水的Water-proofing admixture 防水剂Wire rope 钢绞线Workability measurement 和易性测量Wire mesh 钢丝网Welded mesh 焊接网Wood wool slab 木丝板Water content（moisture content）含水率（湿度）Water absorption 吸水率Wet screening 湿法筛分，湿筛析Wetting and drying 潮湿与干燥Workability control 和易性控制Workability definition 和易性定义Water pepellent admixture 防水剂Water requirement for normal consistency of cement paste 水泥净浆标准绸度用水量Water proofing compound 防水化合物XX-ray diffiraction analysis X射线衍射分析X-ray phase analysis X射线相分析X-rayogram X射线图式X-ray spectrometer X射线光谱仪YYield limit 屈服极限Yield point 屈服点Yield strength 屈服强度Yield stress 屈服应力Yield of steel 钢材的屈服ZZeolite 沸石Zones for sand grading 砂级配区Zeta-potential ζ－电位Zone of heating 预热带。

纳米技术用在化妆品上的作文英文回答：Nanotechnology has revolutionized various industries, and the beauty and cosmetics industry is no exception. The application of nanotechnology in cosmetics has brought about significant advancements and benefits. One of the key areas where nanotechnology has made a remarkable impact is in the formulation and delivery of skincare products.Firstly, nanotechnology enables the development of more effective and targeted skincare products. Nanoparticles can penetrate the skin more efficiently, allowing active ingredients to reach deeper layers and target specific skin concerns. For instance, nanoparticles can encapsulate antioxidants and deliver them directly to the skin cells, providing enhanced protection against free radicals and oxidative stress.Furthermore, nanotechnology has improved the stabilityand longevity of cosmetic products. By reducing the particle size of ingredients, such as pigments and sunscreens, their dispersion and absorption into the skin are improved. This results in better color payoff and longer-lasting effects. Additionally, nanocapsules can be used to encapsulate volatile ingredients, preventing their degradation and enhancing their shelf life.In addition to skincare products, nanotechnology has also influenced the development of makeup products. Nanoparticles can enhance the texture and performance of makeup formulations. For instance, the use of nanoclays in foundation can provide a smooth and lightweight finish, while nanoscale powders in eyeshadows can improve color intensity and adherence.Moreover, nanotechnology has contributed to the development of innovative delivery systems in cosmetics. Nanoemulsions and nanocapsules can encapsulate active ingredients, allowing for controlled release and improved absorption. This enables the formulation of products with enhanced efficacy and targeted benefits. For example,nanocapsules can deliver anti-aging ingredients to specific areas of the skin, such as fine lines and wrinkles,resulting in more visible and long-lasting effects.中文回答：纳米技术在化妆品领域的应用带来了重大的进展和好处。

纳米二氧化钛在生物医学中的应用进展李智;葛少华【摘要】纳米二氧化钛（ nano⁃sized dioxide titanium，nano⁃TiO2）具有较大的比表面积、优良的光催化性能，是目前世界上使用最多的纳米材料之一。

纳米技术的快速发展使得纳米二氧化钛在生物医学领域也得到了广泛的关注和应用，该文综述了纳米TiO2在肿瘤治疗、种植体表面改性、抗菌方面的应用及其可能的不良反应。

%TiO2 nanomaterial is one of the most widely used nanomaterials in the world, which has bigger specific surface area and outstanding performance in photocatalysis. Recently the application of nano⁃sized dioxide titanium in the field of biomedicine has raised much attention because of the advanced development of nanotechnology. This review summarizes the application and the possible adverse reactions ofnano⁃sized dioxide titanium in tumor therapy, implant surface modification and antibacterial aspects.【期刊名称】《口腔医学》【年(卷),期】2017(037)001【总页数】4页(P85-88)【关键词】纳米二氧化钛;光催化;肿瘤治疗;抗菌作用;种植体表面改性【作者】李智;葛少华【作者单位】山东省口腔组织再生重点实验室，山东大学口腔医学院牙周科，山东济南 250000;山东省口腔组织再生重点实验室，山东大学口腔医学院牙周科，山东济南 250000【正文语种】中文【中图分类】R783.1二氧化钛(TiO2)是自然界中天然存在的一种半导体物质，分为金红石、锐钛矿、板钛矿和二氧化钛B几种晶型，具有化学性能稳定、价廉易得、催化活性高、生物相容性好等特点。

表面技术第53卷第4期金属材料表面纳米化研究与进展杨庆，徐文文，周伟，刘璐华，赖朝彬*（江西理工大学 材料冶金化学学部，江西 赣州 341000）摘要：大多数金属材料的失效都是从其表面开始的，进而影响整个材料的整体性能。

研究表明，在金属材料表面制备纳米晶，实现表面纳米化，可以提升材料的表面性能，延长其使用寿命。

金属材料表面纳米化是指利用反复剧烈塑性变形让表层粗晶粒逐步得到细化，材料中形成晶粒沿厚度方向呈梯度变化的纳米结构层，分别为表面无织构纳米晶层、亚微米细晶层、粗晶变形层和基体层，这种独特的梯度纳米结构对金属材料表面性能的大幅度提升效果显著。

根据国内外表面纳米化的研究成果，首先对表面涂层或沉积、表面自纳米化以及混合纳米化3种金属表面纳米化方法进行了简要概述，阐述了各自优缺点，总结了表面自纳米化技术的优势，在此基础上重点分析了位错和孪晶在金属材料表面自纳米化过程中所起的关键作用，提出了金属材料表面自纳米化机制与材料结构、层错能大小有着密不可分的联系，对金属材料表面自纳米化机制的研究现状进行了归纳；阐明了表面纳米化技术在金属材料性能提升上的巨大优势，主要包括对硬度、强度、腐蚀、耐磨、疲劳等性能的改善。

最后总结了现有表面强化工艺需要克服的关键技术，对未来的研究工作进行了展望，并提出将表面纳米化技术与电镀、气相沉积、粘涂、喷涂、化学热处理等现有的一些表面处理技术相结合，取代高成本的制造技术，制备出价格低廉、性能更加优异的复相表层。

关键词：金属材料；表面纳米化；梯度纳米结构；纳米化机理；表面性能中图分类号：TG178 文献标志码：A 文章编号：1001-3660(2024)04-0020-14DOI：10.16490/ki.issn.1001-3660.2024.04.002Research and Progress on Surface Nanocrystallizationof Metallic MaterialsYANG Qing, XU Wenwen, ZHOU Wei, LIU Luhua, LAI Chaobin*(Department of Materials Metallurgy and Chemistry, Jiangxi University ofTechnology, Jiangxi Ganzhou 341000, China)ABSTRACT: It is well known that the failure of most metallic materials starts from their surfaces, which in turn affects the overall performance of the whole material. Numerous studies have shown that the preparation of nanocrystals on the surface of metallic materials, i.e., surface nanosizing, can enhance the surface properties of materials and extend their service life. Surface nanosizing of metallic materials makes use of repeated violent plastic deformation to make the surface coarse grains gradually收稿日期：2023-02-23；修订日期：2023-06-29Received：2023-02-23；Revised：2023-06-29基金项目：国家自然科学基金项目（52174316，51974139）；国家重点研发计划项目（2022YFC2905200，2022YFC2905205）；江西省自然科学基金项目（20212ACB204008）Fund：National Natural Science Foundation of China(52174316, 51974139); National Key Research and Development Program of China (2022YFC2905200, 2022YFC2905205); Natural Science Foundation of Jiangxi Province (20212ACB204008)引文格式：杨庆, 徐文文, 周伟, 等. 金属材料表面纳米化研究与进展[J]. 表面技术, 2024, 53(4): 20-33.YANG Qing, XU Wenwen, ZHOU Wei, et al. Research and Progress on Surface Nanocrystallization of Metallic Materials[J]. Surface Technology, 2024, 53(4): 20-33.*通信作者（Corresponding author）第53卷第4期杨庆，等：金属材料表面纳米化研究与进展·21·refine to the nanometer level, forming nanostructured layers with gradient changes of grains along the thickness direction, including surface non-woven nanocrystalline layer, submicron fine crystal layer, coarse crystal deformation layer and matrix layer, and this unique gradient nanostructure is effective for the significant improvement of surface properties of metallic materials. The process technology and related applications of nanocrystalline layers on the surface of metallic materials in China and abroad are introduced, and the research progress of high-performance gradient nanostructured materials is discussed.Starting from the classification of the preparation process of gradient nanostructured materials and combining with the research results of surface nanosizing in China and abroad, a brief overview of three methods of metal surface nanosizing, namely, surface coating or deposition, surface self-nanosizing and hybrid nanosizing, was given, the advantages and disadvantages of each were discussed and the advantages of surface self-nanosizing technology were summarized. On the basis of this, the key role of dislocations and twins in the process of surface self-nanitrification of metallic materials was analyzed, and the mechanism of surface self-nanitrification of metallic materials was inextricably linked to the material structure and the size of layer dislocation energy, and the current research status of the mechanism of surface self-nanitrification of metallic materials was summarized. Finally, the key technologies required to be overcome in the existing surface strengthening process were summarized, and future research work was prospected. It was proposed to combine surface nanosizing technology with some existing surface treatment technologies such as electroplating, vapor deposition, tack coating, spraying, chemical heat treatment, etc., to replace the high-cost manufacturing technologies and prepare inexpensive complex-phase surface layers with more excellent performance.Techniques for the preparation of gradient nanostructured materials include surface coating or deposition, surface self-nanosizing, and hybrid surface nanosizing. Surface coating or deposition technology has the advantages of precise control of grain size and chemical composition, and relatively mature process optimization, etc. However, because the coating or deposition technology adds a cover layer on the material surface, the overall size of the material increases slightly, and there is a certain boundary between the coating and the material, and there will be defects in the specific input of production applications.In addition, the thickness of the gradient layer prepared by this technology is related to the deposition rate, which takes several hours to prepare a sample. The surface self-nanitrification technique, which generates intense plastic deformation on the surface of metal materials, has the advantages of simple operation, low cost and wide application, low investment in equipment and easy realization of unique advantages. The nanocrystalline layer prepared on the surface of metal materials with the surface self-nanitrification technique has a dense structure and no chemical composition difference from the substrate, and no surface defects such as pitting and pores, but the thickness of the gradient layers and nanolayers prepared by this technique as well as the surface quality of the material vary greatly depending on the process. Hybrid surface nanosizing is a combination of the first two techniques, in which a nanocrystalline layer is firstly prepared on the surface of a metallic material by surface nanosizing technology, and then a compound with a different composition from the base layer is formed on its surface by means of chemical treatment.To realize the modern industrial application of this new surface strengthening technology, it is still necessary to clarify the strengthening mechanism and formation kinetics of surface nanosizing technology as well as the effect of process parameters, microstructure, structure and properties on the nanosizing behavior of the material. For different nanosizing technologies, the precise numerical models for nanosizing technologies need to be established and improved, and the surface self-nanosizing equipment suitable for industrial scale production needs to be developed. In the future, surface nanosizing technology will be combined with some existing surface treatment technologies (e.g. electroplating, vapor deposition, adhesion coating, spraying, chemical heat treatment, etc.) to prepare a complex phase surface layer with more excellent performance, which is expected to achieve a greater comprehensive performance improvement of the surface layer of metal materials.KEY WORDS: metal material; surface nanocrystallization; gradient nanostructures; nanocrystallization mechanism; surface properties金属材料在基建工程、航空航天中扮演着重要角色，随着当今科学技术的高速发展，传统金属材料的局限性日趋明显，开发一种综合性能优异的金属材料迫在眉睫。

文章编号：1673-887X(2023)09-0012-04叶面喷施纳米硅对干旱胁迫下黄瓜幼苗生长及生理的影响罗洁（长江大学文理学院，湖北荆州434020）摘要黄瓜作为我国种植面积最大的瓜类蔬菜，其幼苗在栽培过程中易遭受干旱胁迫，而纳米硅可以提高多种植物的抗性。

以津春4号黄瓜品种为例，通过试验，研究了叶面喷施纳米硅对黄瓜幼苗干旱胁迫耐性的影响。

结果表明：叶面喷施纳米硅可以明显改善干旱胁迫下黄瓜幼苗的表型，提高其株高和叶绿素含量以及抗氧化酶活性。

关键词叶面喷肥；纳米硅；干旱胁迫；黄瓜幼苗中图分类号S642.2文献标志码Adoi:10.3969/j.issn.1673-887X.2023.09.004Effects on the Seedling Growth and Physiology of Cucumber under Drought Stress by Spraying Nano-silicon on Leaf SurfaceLuo Jie(College of Arts and Sciences,Yangtze University,Jingzhou 434020,Hubei,China)Abstract ：As the largest melon vegetable planted in China,cucumber seedlings are vulnerable to drought stress during cultivation,and nano silicon can improve the resistance of many plants.Taking Jinchun No.4cucumber as an example,the effects of spraying nano-silicon on drought stress tolerance of cucumber seedlings were studied.The results showed that the leaf surface spraying of na ‐no-silicon could significantly improve the phenotype of cucumber seedlings under drought stress,and increase the plant height,chlo ‐rophyll content and antioxidant enzyme activity.Key words ：foliar fertilizer spray,nano-silicon,drought stress,cucumber seedling近年来，纳米生物技术已成为研究热点，纳米技术与农业生产的结合也越来越紧密，如纳米农药和纳米肥料等[1，2]。

萘-甲醇标准溶液液相色谱分析条件研究李锋丽许思思张森孙华许爱华黄清波(山东省计量科学研究院，济南2500U)摘要:用液相色谱仪分析萘_甲醇溶液标准物质，通过研究波长、流动相比例、流速、柱温对杂质峰与目标峰的分离度及对目标物的峰面积、峰高的影响，确定了分析萘-甲醇溶液标准物质的最佳条件:波长275nm;流动相比 例 80%(甲醇：水=80 : 20);流速 0.5 mL/min;柱温 40*C。

关键词：液相色谱仪萘-甲醇波长流动相比例流速柱温DOI：10. 3969/j.issn. 1001-232x.2018. 04. 020Research on analytical conditions of naphthalene- methanol standard solution by liquid chromatography. Li Fengli，Xu Sisi，Z h a n g Se n，S u n Hua，Xu Aihua，H u a n g Q in g b o{S h a n d o n g In s t it u t e of M e tro lo g y，J in a n 250014, C h in a)Abstract：T h e naphthalene-methanol standard solution was analyzed by liquid chromatography.Theinfluences of the wavelength,proportion of mobile phase,flow rate and column temperature on the separa­tion degree of the impurity peaks and target peaks were investigated while the effects on the peak areas and peak heights of the target substances were studied as well.T h e optimum conditions were as follows： 275 n m as the wavelength, 80%(the proportion of methanol to water was 80%) as the proportion of mobile phase, 0. 5 m L/m i n as the flow rate and 40°C as the column temperature.Key words：Liquid chromatography；Wavelength；Proportion of mobile phase；Flow rate；Column temperaturei引言液相色谱仪广泛应用于食品、环境等检测领 域，其工作原理是利用液体混合物在流动相与固定 相中的分配或吸附等差异，由流动相将样品带入色 谱柱中进行分离，经检测器检测进行数据处理后，根据保留时间和峰面积（峰高）进行定性定量分析。

有关纳米的英语作文题目400字Nanotechnology: A Promising Frontier with Limitless Possibilities.Nanotechnology, the manipulation of matter on an atomic and molecular scale, has emerged as a transformative field with vast potential to revolutionize various aspects of modern society. This revolutionary technology promises advancements in medicine, engineering, energy production, and countless other industries. In this essay, we will explore the fascinating world of nanotechnology, its current applications, and its boundless future prospects.The World of the Infinitesimally Small.The prefix "nano" is derived from the Greek word for "dwarf," reflecting the incredibly small scale at which nanotechnology operates. One nanometer (nm) is a billionth of a meter, approximately the size of a few atoms arranged side by side. At this minuscule scale, materials exhibitunique properties that differ significantly from their bulk counterparts. This extraordinary phenomenon forms the foundation for the remarkable applications of nanotechnology.Medical Marvels.Nanotechnology holds immense promise forrevolutionizing healthcare. Nanoparticles, designed with specific properties and functionalities, can be engineered to deliver drugs and therapies directly to diseased cells, minimizing side effects and improving treatment efficacy. Additionally, nanotechnology enables the development of highly sensitive biosensors capable of detecting trace amounts of biomarkers, allowing for early diagnosis and precise patient monitoring.Engineering Innovations.In the field of engineering, nanotechnology has ushered in a new era of lightweight, durable, and multifunctional materials. Carbon nanotubes, for instance, areexceptionally strong and possess excellent electrical conductivity, making them ideal for use in aerospace, automotive, and electronics applications. Nanomaterials also find applications in water purification, energy storage, and the development of self-cleaning surfaces.Energy Revolution.Nanotechnology is playing a pivotal role in addressing global energy challenges. The development of highlyefficient solar cells based on nanomaterials promises to harness renewable energy sources more effectively. Additionally, nanotechnology enables the creation of advanced batteries with increased storage capacity and rapid charging capabilities, paving the way for the widespread adoption of electric vehicles.Beyond Current Horizons.While nanotechnology has already made significant contributions to modern society, its full potential remains largely untapped. Future advancements in this field areanticipated to reshape industries and create groundbreaking applications. Some potential frontiers include:Nanorobotics: Microscopic robots that can navigate the human body, perform surgeries, and deliver targeted therapies.Biomimetic Materials: Materials that mimic the structures and functions of biological systems, offering new possibilities for tissue engineering and regenerative medicine.Quantum Computing: The use of nanomaterials to create quantum computers, which possess vastly superior computational power compared to traditional computers.Ethical Considerations.As with any powerful technology, nanotechnology raises ethical questions that must be carefully considered. Potential concerns include environmental impacts, health risks, and privacy issues. Responsible development andcomprehensive regulations are essential to ensure that nanotechnology is harnessed for the benefit of humanity without compromising safety and societal values.Conclusion.Nanotechnology stands at the cusp of a transformative era, offering boundless possibilities for advancements in various fields. Its potential to revolutionize healthcare, engineering, energy production, and countless other industries is truly remarkable. As we continue to explore the world of the infinitesimally small, we embark on a journey of scientific discovery and technological innovation that promises to shape the future of our world in ways we can only begin to imagine.。

Effects of nano-silica on hydration properties of tricalciumsilicateZhenhai Xu,Zonghui Zhou ⇑,Peng Du,Xin ChengShandong Provincial Key Laboratory of Preparation and Measurement of Building Materials,Engineering Center of Advanced Building Materials of Ministry of Education,University of Jinan,Jinan 250022,Chinah i g h l i g h t sNano-silica accelerates C 3S hydration in 3d but reduces hydration rate after 3d. Nano-silica increases C–S–H content but reduces growth rate of C–S–H after 3d. Denser C–S–H with low Ca/Si ratio is formed in the presence of nano-silica. Nano-silica reduces the total porosity of C 3S and optimizes the pore structure.a r t i c l e i n f o Article history:Received 11April 2016Received in revised form 21August 2016Accepted 1September 2016Available online 9September 2016Keywords:Nano-silica C 3SHydration rate Ca(OH)2content C–S–H gelPore size distributiona b s t r a c tIn order to evaluate the influence of nano-silica on tricalcium silicate (C 3S)hydration,hydration rate,Ca (OH)2content,quantification of C–S–H,pore size distribution and micrographs of hydration products were measured.Results revealed that with the increase content of nano-silica,the hydration of C 3S is accelerated before hydration for 3d but slows down in the later age (7d,28d and 60d).C–S–H content increases with the increase content of nano-silica.However,an obvious reduction in C–S–H increment occurs at 7d,28d and 60d.In addition,the hydration products morphology changes from rod-shape to dense matrix at 28d after nano-silica modification,and the Ca/Si ratio of C–S–H gel decreases.Besides,the addition of 3wt.%nano-silica can reduce the total porosity of C 3S by 4.04%and optimize the pore structure.Furthermore,the density of paste increases by 4.22%,which finally leads to the more compact structure of hardened paste.Ó2016Elsevier Ltd.All rights reserved.1.IntroductionNanotechnology is a transformative technology revolutionizing many areas including energy,security,information technology,agriculture,environmental protection and healthcare [1,2].In recent years,the effects of nano-particles on the properties of cement-based materials have been widely investigated due to their fine particle sizes,remarkable surface area and high reactivity [3–5].Using nano-particles can lead to novel properties of cement-based materials such as mechanical properties [6,7]and durability [8–10].The most commonly used nanoparticles in cement-based materials are nano-silica [11–14],nano-CaCO 3[15,16],nano-TiO 2[17–19]and nano-Al 2O 3[20,21],etc.Nano-TiO 2increases the photocatalytic properties in the cement under UV radiation and visible light [22].Nano-Al 2O 3results in enormous improvement in modulus of elasticity but not so much in compres-sive strength [23,24].Nano-CaCO 3increases the compressive strength and the consumption of Ca(OH)2[25].Three synergistic effects are involved in nano-silica modified cement-based materials:(i)Filler pared with traditional mineral admixtures,such as slag and fly ash,nano-silica particles can fill the smaller holes in nano scale,which reduces the porosity of paste and optimizes the distribution of the pore structures [7];(ii)Nucleation effect.During cement hydration,nano-silica parti-cles function as the nucleation sites for the silica units released from cement particles [26].Besides,nano-silica can also act as the C–S–H seeds to accelerate the cement hydration [27];(iii)Poz-zolanic pared with other nano-particles,nano-silica can possess a distinct pozzolanic reaction with cement hydration prod-ucts at early age to promote additional C–S–H gel [7,11,28].Thus,nano-silica modified cement-based materials have been widely/10.1016/j.conbuildmat.2016.09.0030950-0618/Ó2016Elsevier Ltd.All rights reserved.Abbreviations:C 3S,cement clinker mineral:tricalcium silicate;NS0,the C 3S paste made without nano-silica;NS1,the C 3S paste made with 1wt.%nano-silica;NS2,the C 3S paste made with 2wt.%nano-silica;NS3,the C 3S paste made with 3wt.%nano-silica.⇑Corresponding author.E-mail addresses:xuzhenhaimail@ (Z.Xu),mse_zhouzh@ (Z.Zhou).studied.Singh et al.[29,30]have reported thatates C3S hydration and improves C–S–H content atlev et al.[5],Hou et al.[31,32]and Sonebi et al.with the incorporation of nano-silica in paste orlow dosages,nano-silica can significantlymechanical properties of materials.However,theopment rate is lower in the later ages based on[12,33].Researches on strength evolution ofrated cement in the early and later ages are limitedThe aim of this study is to investigate the effectson the hydration properties of cement-basedlater ages.However,it is difficult to preciselynano-silica by using the commercial cement duecompositions and complicated chemical reactionC3S is the major component of Portland cementproperties of cement are mainly depending onC3S.An improved understanding of thenano-silica is the key to understanding theof cement with nano-silica.In the present work,hydration properties of C3S with differentamount of nano-silica in the early and later ages,including hydra-tion rate,Ca(OH)2content,quantification of C–S–H,pore size dis-tribution and micrographs of hydration products,have been investigated.All of these results aim to provide a comprehensive explanation for the modification effects of nano-silica on C3S.2.Materials and methods2.1.Raw materialsC3S used in this study was prepared by high-temperature calci-nation method.The mixture of CaCO3and SiO2(3:1M ratio)was calcinated at1550°C for6h,followed by cooling down and grind-ing the synthesized C3S,glycol-ethanol method(Chinese National Standard GB/T176-2008)was used to determine free lime(f-CaO)content.After three times calcination the f-CaO content was less than0.8%.The particle size distribution of C3S(Fig.1)shows the particle size ranges from7nm to40nm,moreover,the specific surface area is300m2/g(BET).2.2.Experimental programs2.2.1.Mixing proportionsIn this study,4groups of C3S pastes at different proportions were prepared.For all samples,water to cementing material ratio (the ratio of water to C3S and nano-silica)was0.4.The proportions of nano-silica added into the samples were0wt.%,1wt.%,2wt.% and3wt.%of the C3S and labeled as NS0,NS1,NS2and NS3,respec-tively.However,the addition of nano-particles to cementitious material could reduce the workability due to its high specific sur-face area[26,35].In order to get the samefluidity of the samples, naphthalene-based superplasticizer was added.The specific pro-portions are shown in Table1.2.2.2.Preparation of paste samplesThe nano-particles are often in an aggregated(firmly-held clus-ters)or agglomerated(loosely-held clusters)form withfinal grain size from submicron to as high as100l m due to their very high specific surface area and energy[36,37].The sample preparation process used in this study wasfinalized after several preliminary experiments.First,nano-silica and all water were added to a bea-ker and dispersed by an ultrasonic disperser(operating frequency is40kHz,ultrasonic electric power is50W)for5min,then they were added into a small agitator with C3S and stirred for4min. Thefinal mixtures were made into2cmÂ2cmÂ2cm samples. All samples were cured at20±1°C and90%RH until testing.To evaluate pozzolanic activity of nano-silica,20g Ca(OH)2was mixed with3g nano-silica and the water to cementing material ratio was2.The mixtures were sealed in centrifuge tubes to pre-vent carbonation until testing.The Ca(OH)2content at different ages were determined by TGA technique.Fig.1.Particle size distribution of C3S particles.Fig.2.XRD pattern of unhydrated C3S.Table1Proportions of C3S pastes.Sample C3S(g)Nano-silica(g)Naphthalene-basedsuperplasticizer(g)H2O(g)W/C*NS010000400.4 NS19910.2400.4 NS29821400.4 NS3973 2.5400.4*W/C is the ratio of water to C3S and nano-silica.1170Z.Xu et al./2.2.3.Calorimetric measurementsAn isothermal calorimeter(TAM Air C80,Sweden)operating at 25°C was used to determine the hydration heatflow.The heatflow was recorded every22s for72h.The reproducibility of the results was checked.Duplicate tests show that the total heat measure-ments are within±3%.Exothermic rates are essentially identical. Table2shows the proportions of C3S-nano-silica-H2O samples. 2.2.4.Semi-quantitative X-ray diffraction analysisIn present work,semi-quantitative analysis ofcarried out by comparing the intensities of thewhich was used to semi-quantitatively assess of monosulfoaluminate hydrate(AFm)and Friedel’spastes[38,39].All samples werefinely groundedform the powder diffraction measurements.Thedata from50°to53°(2h)was collected by an(Bruker,D8Advance,Germany)under ambientaccelerate voltage,accelerate current,step sizeof the tests were40kV,40mA,0.02°and3s,intensities of characteristic peaks of C3S at51.4°,were measured[40].The area between the peakis integrated to indicate the relativeC3S.Each sample was tested three times and theeach sample was presented to get a2.2.5.Thermogravimetric analysisAn integrated thermal analyzer(Mettler,land)was used to test Ca(OH)2content andcation of C–S–H in the present study.Samplesinert Ar atmosphere(gasflow rate was201000°C at a heating rate of10°C/min.Beforedried at60°C for4h and ground to less than200Duplicate tests were carried out to get a2.2.6.Morphology analysisThe influence of nano-silica on morphology of Cstudied through scanning electron microscopeLS15,Germany).At the end of curing,sampleswashed twice with ethanol,dried at80°C for2h.coated with gold to make it conductive and wereThe Ca/Si ratio of the C–S–H gel in thedetected by EDS.2.2.7.Mercury intrusion porosimetryMercury intrusion porosimetry(MIP,18,USA)technique was used to quantitativelysize distribution of the samples with and28d.Each sample was tested two times to get aresult.The intrusion pressure of MIP ranges fromand pore diameter ranges from0.0035to200l m.28d,samples were vacuum-dried at60°C for24hin order to avoid structural damage[41,42].Each1.2g sample and the size was less than8mm.3.Results and discussion3.1.Pozzolanic activity of nano-silicaCa(OH)2adsorption capacity of nano-silica has investigated to evaluate pozzolanic activity of nano-silica.The Ca(OH)2adsorption capability of nano-silica in Fig.3shows that Ca(OH)2content decreases rapidly before7d and the depletion rate slows down after7d,indicating that the pozzolanic reaction mainly occurs before hydration for7d.It’s in good agreement with experimental results presented by Hou et al.[43],in which the pozzolanic reac-tion of nano-silica(the specific surface area is$150m2/g)is almost complete after7days of hydration and another nano-silica(the specific surface area is$450m2/g)only takes70h to complete the pozzolanic reaction.Compared with traditional mineral admixtures,such asfly ash and silica fume,the specific surface and atoms number in the sur-face of nano-silica increase rapidly.Owing to atoms in surface of Fig.3.The Ca(OH)2adsorption capability of nano-silica.Table2Proportions of C3S-nano-silica-H2O samples.Sample m(C3S)/g m(SiO2)/g m(H2O)/g W/C*NS0 2.8571020.7NS1 2.82850.028620.7NS2 2.80000.057120.7NS3 2.77140.085720.7*W/C is the ratio of water to C3S and nano-silica.4.The total hydration exothermic curves of C3S with different nano-silicacontent(W/C=0.7).Z.Xu et al./Construction and Building Materials125(2016)1169–11771171B Si A O AþH A OH!B Si A OHðreact quicklyÞ;ð1ÞB Si AþOH!B Si A OHðreact quicklyÞ;ð2ÞB Si A OHþCaðOHÞ2!C A S A H:ð3Þ3.2.Early hydration rateThe total hydration exothermic curves in Fig.4show that greater hydration heat appears when nano-silica is added,even at the very beginning contacting with water.During thefirst10h of hydration,the total hydration heat of C3S with1wt.%,2wt.%, 3wt.%nano-silica increases by82%,180%,237%than control sam-ple(NS0).What’s more,the total hydration heat of C3S with1wt.%,reaction,and the main peak corresponds to the middle-stage reac-tion.The exothermic rate of NS1,NS2and NS3in peak1position increase obviously than control sample.Partial enlarged drawing of peak2is shown in Fig.5(b).It can be observed that the exother-mic rate of NS1,NS2,NS3in peak2position are88%,189%,237% higher than control sample.Besides,NS1,NS2,NS3in peak2posi-tion appears34min,55min and70min in advance compared with pure C3S.The results in Fig.5show that wetting,dissolution,accel-eration periods and deceleration period process of C3S accelerate with the increase content of nano-silica.The acceleration of hydra-tion rate is due to the nucleation effect of C–S–H seeds which pro-vides additional nucleating sites and accelerates the hydration rate as well as the growth of hydrated products[30],on the other hand, the pozzolanic effect of nano-silica is contributed to the accelera-tion effect[29].Similar conclusion also can be seen in cement-nano-silica system[49].Fig.5.(a)The hydration exothermic rate curves of C3S with different nano-silica content(W/C=0.7),(b)Partial enlarged drawing of peak2in Fig.5(a).6.The intensities of characteristic peaks at51.4°,51.7°and51.9°vs.curing 3S with different nano-silica content.1172Z.Xu et al./Construction and Building Materials125(2016)1169–1177of Ca(OH)2[51].The start and end points of the Ca(OH)2decompo-sition are determined through utilization of the second derivative curve.The mass loss is evaluated by using the vertical distance between two tangential lines.This vertical distance is specifically taken at the inflection point of the TGA curve(easily indicated by the peak on thefirst derivative curve).The possibility will always exist that carbonation of the Ca(OH)2will occur[11,51].Therefore, the carbonation effects of Ca(OH)2are taken for the quantification of Ca(OH)2to get an actual amount.The thermogravimetric analysis of C3S with different nano-silica was tested at3d,7d,28d and60d and the result shows that the mass loss mainly occur in two stages,including mass loss due to the decomposition of Ca(OH)2and CaCO3(carbonation of Ca (OH)2).The following equation is used to determine the Ca(OH)2 content of C3S samples:w CH¼74:1=18Ãm1þ74:1=44Ãm2;ð4Þw CH–the content of calcium hydroxide(wt.%);74.1/18–the molar weight ratio of Ca(OH)2to H2O;m1–the percentage of mass loss due to the decomposition of Ca(OH)2(wt.%);74.1/44–the molar weight ratio of Ca(OH)2to CO2;m2–the percentage of mass loss due to the decomposition of CaCO3(wt.%).Ca(OH)2content in C3S samples are obtained by thermogravi-metric analysis and the results are presented in Fig.7.Before hydration for3d,the nano-silica addition can increase the Ca (OH)2content:the Ca(OH)2content in NS1,NS2and NS3are39%, 52%and66%more than that in control sample(NS0),which reflects the higher hydration acceleration with the increase content of nano-silica.This result coheres with the result of hydration rate (Fig.5and Fig.6).However,the Ca(OH)2content of all samples is almost at the same level at7d.The reasons are as follows:the hydration rate of C3S in NS0,NS1,NS2and NS3slows down sequentially with the increase content of nano-silica after3d (Fig.6),which means that the Ca(OH)2content generated at3–7d decreases with the increase content of nano-silica(i.e.gener-ated Ca(OH)2:NS0>NS1>NS2>NS3);on the other hand,the poz-zolanic reaction with nano-silica causes an evident reduction in Ca (OH)2content before hydration for7d(Fig.3),which means that nano-silica after7d.This is consistent with the results of anaphase hydration rate.3.3.3.Quantification of C–S–HQuantification of C–S–H in NS0,NS1,NS2and NS3at different time of hydration has carried out using following equation by TG analysis[29].C A S A Hð%Þ¼Total LOIÀLOIðCHÞÀLOIðCCÞ;ð5ÞLOIðCHÞð%Þ¼CaðOHÞ2mass losssample mass at1000 CÂ100ð6ÞLOIðCCÞð%Þ¼CaCO3mass losssample mass at1000 CÂ100ð7ÞTotal LOI–total loss of ignition;LOI(CH)–the dehydration of Ca(OH)2;LOI(CC)–the carbon dioxide release of CaCO3.The content of C–S–H at different time(3d,7d,28d and60d) is presented in Fig.8.Results show that C–S–H content increases with the increase content of nano-silica.However,an obvious reduction in C–S–H increment occurs with the increase content of nano-silica in the later age(7d,28d and60d).The development of C–S–H content can be divided into3stages:(i)Before hydration for3d.Higher content nano-silica produces more C–S–H gel(the increment of C–S–H before3d:NS3=7.64%,NS2=6.07%, NS1=4.99%,NS0=2.68%),showing the acceleration in hydration rate due to the nucleation effect of C–S–H seeds[30]and the poz-zolanic effect of nano-silica[29].(ii)Hydration at3–7d.Higher content nano-silica produces less C–S–H gel(the increment of C–S–H at3–7d:NS3=1.70%,NS2=1.99%,NS1=2.24%, NS0=3.17%),showing the inhibition in hydration rate even in the presence of pozzolanic effect of nano-silica which is con-tributed to increase the C–S–H content.(iii)Hydration at7–60d. Higher content nano-silica produces less C–S–H gel as well(the increment of C–S–H at7–60d:NS3=1.36%,NS2=2.04%, NS1=2.09%,NS0=3.72%),the pozzolanic reaction is almost com-plete after7d(Fig.3).Consequently,it can be seen that the hydra-tion rate of C3S slows down with the increase content of nano-7.Ca(OH)2content vs.curing age of C3S with different nano-silica content.Quantification of C–S–H vs.curing age of C3S with different nano-silica content.Z.Xu et al./Construction and Building Materials125(2016)1169–11771173distinguish the influence of different pore sizes on the cement-based materials and compare conveniently,the pores in cement-based materials are divided into the harmful pore (＞200nm),less harmful pore (20–200nm)and harmless pore (＜20nm)[53].The cumulative intrusion curves per gram in function of the pore diameter are shown in Fig.9(a).According to the volume of the mercury intruded per unit mass of the sample,the internal pores in NS3are great impacted because of the addition of nano-silica.The total porosity of NS3decreases by 4.04%compared with NS0(detailed data are shown in Table 3).In addition,the density of NS3increases by 4.22%compared with the control sample which means that a more compact structure is formed.This is in agree-ment with a previous work by Ehsan Ghafari et al.[54],in which the total porosity of samples with 4wt.%nano-silica decreases by 24.5%and the density increases as well.The pore size distribution curves,as shown in Fig.9(b),indicate that the pores of C 3S paste are refined by nano-silica.Harmful pores are remarkably decreased.Besides,less harmful pores are also reduced and these holes are transformed into harmless pores (detailed data are listed in Table 3).This results suggest that the variation of pore size distribution in this region could affect thepermeability of C 3S at some extent [8,42,55].According to Rong et al.[9],nano-silica addition can function as a filler for pores in the materials and also creates discontinuity of capillary pores by formation of more C–S–H gel in nano-silica-cement system.3.3.5.Micrographs of hydration productsNano-silica particles are found to influence hydration behavior and lead to differences in the microstructure of hardened cement based materials [33,46].The most representative samples NS0(control sample)and NS3are selected for hydration products mor-phology analysis.Morphologies of C 3S hydration products with and without nano-silica are presented in Fig.10.After curing for 3d,both sam-ples generate immature hydration products:as shown in Fig.10(a),rod-shape hydration products are observed in control sample.Fig.10(c)shows that irregular granular products are generated in NS3.Moreover,the microstructure are obviously different between two samples at 28d:Fig.10(b)shows that with the hydration of C 3S,the rod-shape hydration products in control sample grow up and many needle-like hydration products on the surface,pores of varying sizes are noticeable among the solids,this has also been reported in Ref.[56].Nevertheless,the hydration products in NS3further grow up to be the denser matrix which has a smooth sur-face,shown in Fig.10(d).The additional C–S–H formed by nucle-ation and pozzolanic reaction of nano-silica densifies the microstructures,and produces a more homogeneous microstruc-ture.This is consistent with pore size distribution analysis:the C 3S sample with nano-silica has lower porosity and higher density.EDS analysis of hydrated products are shown in Fig.11,the average value of Ca/Si ratio of each sample is determined by dot-scanning with 11points to get a representative result.It can be seen from Fig.11that the Ca/Si ratio of C–S–H in NS0is very high at 3d,which converts into low C/S ratio at 28d (2.41at 3d,and 2.13at 28d).In the case of NS3,C–S–H gel has lower Ca/Si ratio (2.04at 3d,and 1.41at 28d)compared to NS0,which is con-tributed to the formation compact or denser C–S–H.It’s beneficial to improve the permeability resistance of C–S–H [57,58]prehensive effects of nano-silica on C 3S hydrationIt is important to understand how nano-silica affect the cement hydration process.However,due to the complex compositions and complicated chemical reaction during hydration,the mechanism is not very clear.Hydration properties of C 3S with different amount of nano-silica in the early and later ages has been focused in the present study to better understand the mechanism.Pozzolanic activity of nano-silica analysis (Fig.3)shows that the pozzolanic reaction mainly occurs before hydration for 7d,the rapid poz-zolanic reaction is attributed for the high surface energy of nano-silica and high activity atoms in the surface (unsaturated bonds …Si A O A and …Si A )[45].Early hydration rate (before 3d)in Fig.5shows that the wetting,dissolution,acceleration periods and deceleration period process of C 3S accelerate with the increase content of nano-silica.What’s more,the total hydration heat of C 3S with 1wt.%,2wt.%,3wt.%nano-silica increases by 65%,129%,154%respectively than control one at 72h.The nucleation effect of C–S–H seeds and the pozzolanic effect of nano-silicais9.(a)Cumulative intrusion per gram of NS0and NS3,(b)Pore size distribution NS0and NS3.Table 3Bulk density,most probable pore size,total porosity and pore size distribution of NS0and NS3.Sample Density (g/cm 3)Most probable pore size (nm)Total porosity (%)Harmful pores (>200nm,%)Less harmful pores (20–200nm,%)Harmless pores (<20nm,%)NS028d 1.6672021.1858.6426.4714.89NS328d1.731517.144.3123.8471.85Materials 125(2016)1169–1177contributed to the acceleration effect[29,30].Further anaphase hydration rate results(Fig.6)also show the acceleration effect of nano-silica before3d.However,the rate of hydration slows down at later ages(i.e.7,28and60d).A coating of hydrates formed on the surface of unhydrated C3S particles is considered to be less per-meable and hinders C3S hydration in the later age[33].In addition, Ca(OH)2content result(Fig.7)reveals that Ca(OH)2content in NS1, NS2and NS3are39%,52%and66%more than that in control sam-ple(NS0)before3d,which reflects the higher hydration accelera-tion with the increase content of nano-silica.When hydration for 7d,the Ca(OH)2content of all samples is almost at the same level. The inhibition effect of nano-silica on C3S hydration after3d(ana-phase hydration rate)and the pozzolanic reaction(pozzolanic activity of nano-silica analysis)are responsible for the phe-nomenon.After curing for7d,the pozzolanic reaction is almost complete(Fig.3)but the Ca(OH)2content in NS1,NS2and NS3 decreases in turn,which indicates nano-silica hinders C3S hydra-tion.These results are consistent with the analysis of early and anaphase hydration rate.Quantification of C–S–H analysis(Fig.8)showstent nano-silica produces more C–S–H gel(thebefore3d:NS3=7.64%,NS2=6.07%,NS1before3d,indicating the acceleration inhydration for3d,Higher content nano-silicaH gel(the increment of C–S–H atNS2=4.03%,NS1=4.33%,NS0=6.89%)showinghydration rate even in the presence of pozzolanicsilica(before7d).Therefore,we can concluderate of C3S slows down with the increaseafter3d.The results are in agreement withtion rate and Ca(OH)2content.Furthermore,gel generated by nucleation and pozzolanic(before7d)improves the pore structure,densityraphy of NS3even in the presence of inhibitionafter3d:the total porosity of NS3decreasessity increases by4.22%compared to NS0,Harmfulharmful pores are also reduced and these pores are transformed to harmless pores.In addition,denser C–S–H with low Ca/Si ratio is formed in the presence of nano-silica.To sum up,nano-silica accelerates C3S hydration at early age (i.e.3d)but the rate of hydration slows down at later ages(i.e. 7,28and60d).All the analyses of early hydration rate, anaphase hydration rate,Ca(OH)2content and quantification of C–S–H prove the above conclusion.Ultimately,incorporation of nano-silica improves the C–S–H content,pore structure,density and microtopography of C3S sample.All of these results provide a comprehensive explanation for the effects of nano-silica on C3S hydration.4.Conclusions and recommendationsThe experimental study herein described was conducted aiming to evaluate the effects of nano-silica on hydration properties of C3S in the early and later ages.The following conclusions are drawn:of NS0hydration products at3d,(b)SEM micrograph of NS0hydration products at28d,(c)SEM micrograph of NS3hydration hydration products at28d.EDS results of hydrated C3S samples with and without nano-silica at3dd.(1)The pozzolanic reaction of nano-silica mainly occurs beforehydration for7d.(2)The hydration process of C3S,including wetting,dissolution,acceleration periods and deceleration period,is accelerated with the increase content of nano-silica before hydration for3d.On the other hand,the rate of hydration slows down with the increase content of nano-silica in the later age(7d, 28d and60d).(3)With the increasing amount of nano-silica,Ca(OH)2contentin NS0,NS1,NS2and NS3increases orderly at3d but reduces in turn at7d,28d and60d.(4)C–S–H content increases with the increase content of nano-silica.However,an obvious reduction in C–S–H increment occurs in the later age(7d,28d and60d).(5)The denser C–S–H with low Ca/Si ratio is formed in the pres-ence of nano-silica,and the morphology changes from rod-shape to dense matrix at28d.(6)The addition of nano-silica can reduce the total porosity ofC3S and optimize the pore structure.Besides,the increased density of NS3finally leads to a more compact structure of the hardened paste.In a word,the addition of nano-silica can accelerate the early hydration and optimize the pore structure,nevertheless,it decreases the later hydration rate at7d,28d and60d.More stud-ies should be carried out on C–S–H gel and the mechanism of low-ering the rate of hydration in the later stage in future. 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