外文翻译

外文翻译
外文翻译

二氧化硅包覆锰锌铁氧体纳米粒子的制备及表征

摘要

锌取代锰铁氧体(Mn0.4Zn0.6Fe2O4)磁芯和二氧化硅(SiO2)壳组成的核/壳纳米粒子通过溶胶凝胶法制成,该方法利用正硅酸乙酯(TEOS)作为二氧化硅;铁盐、锰盐和锌盐则作为铁氧体的前驱体,用二氧化硅的三种不同的质量百分比来包覆纳米粒子。X射线衍射法证实了磁性纳米粒子是无定形二氧化硅与尖晶石混合状态。在不同温度下煅烧后样品的粒度大小是使用德拜-谢勒方程的X射线衍射图谱的311线的宽度估计。通过高分辨率透射电镜(HRTEM)测定几个选定样品,可以得出关于晶体结构与粒子尺寸的信息与通过X射线衍射法所得到的信息一致。高分辨透射电镜结果表明,二氧化硅包覆在纳米粒子上,计算得包覆层厚度与从高分辨透射电镜图片测定一致。在温度范围内300至5 K测定的磁滞回线和室温下的穆斯堡尔光谱表明纳米粒子的超顺磁性。

1.前言

用各种非磁性纳米粒子的表面包覆磁性纳米粒子形成的核/壳结构的新材料[1-4],不仅开辟了各种电子设备的多维工业应用[5-11],而且还带来了各种生物医学应用[12-14]. 这些核/壳结构的纳米材料广泛应用于磁记录介质、催化剂,、铁磁流体,、药物输送和微波吸收[6,15]。这个外壳可以保护磁性纳米粒子免受环境侵蚀及有效地增加邻近磁性纳米粒子之间的距离,从而在某种程度上减少纳米粒子的磁耦合度[16]。由于铁氧体在很大程度上具有高电阻率[17]和低生产成本[18–20]的优点,通常用于制造各种形状的变压器铁心,在这方面尖晶石的软磁铁氧体混合材料由于其磁特性容易被修饰已引起了高度重视[1-4,10]。就目前来说,在纳米科学和纳米技术领域开发一种新的具有较好稳定性的磁纳米材料的制备方法是一个挑战性的尝试。为了改善表面特性和保护在反应试剂中免受腐蚀,磁纳米粒子已用多种不同的方法来制备。

具有纳米粒子大小的混合尖晶石锰锌铁氧体是一种重要的软磁材料,因为它具

备应用在各种磁性器件上的潜力。我们报导了锌取代锰铁氧体(Mn

0.4Zn

0.6

Fe

2

O

4

)核和

二氧化硅(SiO

2

)壳组成的核/壳纳米粒子的表征和制备方法。一种新颖简单的溶胶凝胶方法已经被用于制备核/壳结构的纳米粒子。系统地研究了不同二氧化硅的

重量百分比制备核/壳结构的材料。二氧化硅包覆锰锌铁氧体纳米粒子准备三组,依次质量比为9%、16%、25%。另外未包覆二氧化硅的铁氧体也被制备.所有这四个批次的在不同温度下煅烧,即400 , 600 , 800和1000℃下分别煅烧4小时,以获取不同尺寸的纳米粒子。X射线衍射、高分辨透射电子显微镜、磁性和穆斯堡尔效应被用于测试纳米粒子的特性。利用德拜-谢勒方程的X射线衍射图谱的311线估计出的纳米粒子的粒径在4-26nm范围内. 在温度范围内300至5 K下的直流磁化测量得到的穆斯堡尔光谱表明纳米粒子的超顺磁性。

2.实验

包覆二氧化硅的锰锌铁氧体的混合尖晶石纳米粒子可通过一个简单的溶胶凝

胶法制成。首先准备化学药品,是由MnCl

2?4H

2

O、ZnSO

4

?7H

2

O和无水FeCl

3

组成的。

铁氧体中锰、锌和铁盐的比例为0.4:0.6:2.0。将这些盐放入烧杯在80℃搅拌一小时,再逐滴加入25%的氨溶液,直至生成共沉淀物,溶液PH值保持在10再继续剧烈搅拌半小时至共沉淀成为氢氧化物。然后,过滤沉淀后的金属氢氧化物并彻底清洗去除多余的离子,将过滤得到的共沉淀氢氧化物,放入100℃烘箱中干燥24小时。将柠檬酸溶解在150ml去离子水中,再将干燥后的氢氧化物加入其中并用力搅拌,在恒温100℃下持续搅拌3小时,随后将TEOS缓慢添加进去,恒温100℃下再继续搅拌6小时。形成的凝胶在玻璃培养皿中缓慢蒸发。为了磁性纳米粒子的核壳结构稳定,对纳米粒子包覆的二氧化硅采取三种不同的质量百分比,分别是:9%、16%、25%。将这四组样品(3个包覆二氧化硅和1个未包覆二氧化硅的纳米粒子样品)分别在400、600、800、1000℃下进行煅烧。

X射线衍射图谱采用Brukers Advanced D8衍射仪,Cu Ka辐射、2θ在 20℃- 70℃.电子显微照片通过JEOL 2010电子显微镜获得,在室温至5K之间,直流磁测量方式使用振荡样品磁强计进行,该磁强计最大用磁场范围可达1T. 穆斯堡尔效应的测量使用了一种基于PC的分光计,它具有1024个微通道卡,可加速模式转换。所有测量都使用10mCi57Co源,用 Rh 矩阵。分光计是用12mm厚的高纯度天然铁箔标定的。

3.实验结果及结论

3.1 XRD分析

对样品而言,一个典型的X射线衍射图 [Mn

0.4Zn

0.6

Fe

2

O

4

]

(1-x)

[SiO

2

]

(x)

(x= 0,

0.09, 0.16, 0.25)如图1显示。XRD图谱中的峰值与混合尖晶石锰锌铁氧体系统[ 8 ]记录的完全符合,证实了在目前混合尖晶石铁氧体的结构。此外,如果样品煅烧超

过600℃会观察到a-Fe

2O

3

的峰(104),而在1000℃下煅烧a-Fe

2

O

3

的含量估计为

4%,锰锌铁氧体中a-Fe

2O

3

的形成也被Rath 等发现[21].四组样品的粒径都是通过德

拜-谢勒方程计算得到的,D = 0.89λ/(βcosθ),其中λ为辐射波长,β为半峰宽,θ为衍射角度。计算出的平均粒径范围是4至26nm。表1显示了纳米粒径与煅烧温度的关系。

图1.煅烧在800℃的[Mn0.4Zn0.6Fe 2O 4](1-x) [SiO2 ](x)表1.不同涂层比例的Mn0.4Zn0.6Fe 2O 4的(x= 0, 0.09, 0.16, 0.25)的X射线衍射图粒径、煅烧温度、格参数关系图3.2 HRTEM分析

HRTEM测试了三种纳米粒子样品,其中两种为包覆25%的二氧化硅并分别在600和1000℃下煅烧,另一种未包覆二氧化硅的样品在1000℃煅烧。电镜照片、选区电子衍射图和晶粒边缘通过HRTEM测试得到。图2给出了几个有代表性的图片,图2(a)显示了包覆层为25%二氧化硅并在600℃煅烧的锰锌铁氧体,这个数据明确表明了该铁氧体纳米粒子被二氧化硅包覆。为了准确地估算出纳米粒子的平均粒径,大部分粒子样品的半径都来自这三种不同粒子样品的显微图片。从显微图片中获得的粒径与那些通过XRD获得的数据相吻合。图2(b)显示了煅烧在1000℃

下的锰锌铁氧体的选区电子衍射图。混合尖晶石纳米粒子的不同特征线,即(111)、(220)、(311)、(400)、(511)、(440)和(533)如图图2(b)所示。SAED图所得到的结果与XRD所得数据是一致的。从其他两种样品即包覆有25%二氧化硅并在600和1000℃下煅烧所得的结果也同样符合混合尖晶石体系。为了估计包覆层厚度,一个纳米粒子在HRTEM测试中被观察到,相应的图片如图2(c)所示,同时,我们还可以看出球形锰锌铁氧体纳米粒子的核表面覆盖着一层均匀连

续的SiO

2壳,厚度约为2.88nm,这个厚度同样可以通过SiO

2

的质量百分比和平均

粒径(HRTEM显微图片所得)得到,是1.70nm,相对较低的计算结果可能是由于体系中纳米粒子的粒度分布。图2(d和e)显示显示了晶格边缘涂着二氧化硅层。这些条纹是一组相距0.29nm原子面与相邻面组成的,相当于(220)混合尖晶石铁氧体面。包覆层未发现晶型,这说明了二氧化硅涂层是无定形状态。同样,在涂层样品的XRD图谱也没有与二氧化硅相符合的峰出现,因此,可以很明显地看出处在核/壳结构中二氧化硅是无定形的。从不同的样品电镜图片得到的粒径分布结果在柱状图2(f)中显示.涂层25%二氧化硅并在600℃下煅烧的锰锌铁氧体的粒径符合了对数函数,这种对应关系如柱状图(图2(f))。对数函数得到的平均粒径是13nm,这和通过XRD得到的11nm符合。

图2.(a)纳米粒子的HRTEM图(b)煅烧在1000℃下图3. 煅烧在1000℃下的包覆(x=0.25)的样品的未包覆的锰锌铁氧体的选区电子衍射图(c) 在300K至5K区间的磁滞回线煅烧在1000℃下的包覆(x=0.25)的锰锌铁氧体的显微图(d)

煅烧在1000℃下的包覆(x=0.25)的样品涂层(e) 煅烧在

1000℃下的包覆(x=0.25)的样品条纹(f) 煅烧在600℃下

的包覆(x=0.25)的样品粒径和对数函数对应的柱状图

3.3 磁性能分析

图3显示了煅烧在1000℃并涂层25%二氧化硅的锰锌铁氧体在不同温度下即300、200、100和5K所形成的磁滞回线,从图中可以看出在300、200、100和5K 温度下矫顽力分别是100、104、195和807Oe. 这种矫顽力随温度降低而减低的关系表明了不是所有的纳米粒子在室温下都处在超磁化状态,而有一小部分的纳米粒子处在亚铁性有序状态,这是由样品中的粒子分布所引起的。在室温下高于临界粒径的粒子处在亚铁磁有序状态,这些粒子造成了室温矫顽力的有限值。随着温度的降低,越来越多的超磁微粒进入相应的亚铁磁性有序状态,这通常受温度的影响。此外,从矫顽力的变化可以明显看出一大部分超磁微粒仍保持在超顺磁状态低至100K,使得数目的急剧下降的原因便是矫顽力的急剧上升,那么,在温度低于100K 的情况下,相当一部分超磁微粒进入亚铁磁有序状态。因此,显示出了超磁温度必须低于100K。这种超顺磁状态也在穆斯堡尔图谱显现出来了(将在下一部分进行讨论)。在5K 温度下应用1T测量样品的饱和磁化强度值为32.08emu/g,这一数据接近于铁氧体纳米粒子的40 emu/g,如果我们排除了该样品中存在非磁性部分(指二氧化硅)。矫顽力的热变化如图4所示,该图显示了100K以下的急剧增加。低温下矫顽力的变化所显示出的超顺磁特征也反映了磁化曲线变化中温度函数。从温度和磁化曲线估计出的抑制温度是51K,这同在100K温度下观察磁滞回线所得到的矫顽力急剧上升相一致。

图4. 煅烧在1000℃下的样品矫顽力的热变化

3.4 穆斯堡尔分析

两批样品(未涂层铁氧体和涂层25%二氧化硅)的穆斯堡尔图谱分别如图5、

6所示。煅烧在400℃温度下涂层和未涂层的铁氧体纳米粒子所得穆斯堡尔图谱是一个双线,表明了完全超顺磁的存在,例如所有粒径都低于现存的混合尖晶石铁氧体纳米粒子的临界粒径。当煅烧温度上升至600℃时,将会发现双线变为明显的六重线。涂层和未涂层的样品所的的光谱图显示了一个双线六重线的叠加。使用基于最小化的伦兹线拟合程序所得光谱可被反旋转。图5显示了未包覆样品的室温穆斯堡尔谱,图6显示了包覆样品的室温下穆斯堡尔谱,表2列举了提取出的超精细参数。样品中的同构异体的偏移值表明了样品中仅存在Fe3+氧化态。该偏移值几乎是相同的,这表明没有发生从壳到核的电子转移。双线的四极分裂同相应的六重线相比更多,这是由于这样一个事实,较小的粒子通常具有较低的铁核对称性,而较低的铁核对称性又是由于大范围的表面缺陷。煅烧在600和1000℃下的样品超精细值在50.5与51之间变化,这是体系的典型变化。在温度由600上升至1000℃下,铁氧体氧化与六重线强度关系如表2所示。有趣的是,在600至1000℃下煅烧的涂层的铁氧体的六重线强度几乎保持不变。我们知道,带有非磁性壳的磁性纳米粒子的涂层一般影响能源屏障,是因为粒子内部磁耦合度的降低。相对强度值的基本不变可能正是二氧化硅壳对粒子内部相互调节的表现。

图5.分别煅烧在1000℃、600℃、400℃未包覆样品图6.分别煅烧在1000℃、600℃、400℃包覆的穆斯堡尔谱样品(x=0.25)的穆斯堡尔谱

表2. 穆斯堡尔谱中提取出的超精细参数

4.结论

核/壳结构(Mn

0.4Zn

0.6

Fe

2

O

4

)

(1-x)

(SiO

2

)x (x = 0.09, 0.16, 0.25)纳米复合材料

采用溶胶凝胶法制备。所有样品的X射线衍射显示没有峰与二氧化硅相应,这表明所有的锰锌铁氧体的纳米粒子在二氧化硅的非晶矩阵中被核化。X射线衍射中的所有峰证实锰锌铁氧体的混合尖晶石态的形成。几个选定样品的HRTEM测试还表明了纳米粒子是单晶粒,HRTEM观察得到的晶体结构与XRD所得到的一致。HRTEM观察也表明了纳米粒子被二氧化硅很好地包覆。从选区电子衍射图估计到的各种d

hkl

值与从X射线衍射得到的一致。通过德拜-谢勒方程X射线衍射的(311)线估计出的粒径同纳米粒子的电镜图片得到的粒径是一致的,粒径范围是4至26nm。磁滞回线是在温度300至5K观察的,在室温下记录的样品的穆斯堡尔谱表明纳米粒子处在超顺磁状态。

知识

作者们希望感谢DST,正是由于印度政府给这项研究提供了资金支持(工程号SR/S2/CMP-43/2006)。

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工业设计原著选读 优秀的产品设计 第一个拨号电话1897年由卡罗耳Gantz 第一个拨号电话在1897年被自动电器公司引入,成立于1891年布朗强,一名勘萨斯州承担者。在1889年,相信铃声“中央交换”将转移来电给竞争对手,强发明了被拨号系统控制的自动交换机系统。这个系统在1892年第一次在拉波特完成史端乔系统中被安装。1897年,强的模型电话,然而模型扶轮拨条的位置没有类似于轮齿约170度,以及边缘拨阀瓣。电话,当然是被亚历山大格雷厄姆贝尔(1847—1922)在1876年发明的。第一个商业交换始建于1878(12个使用者),在1879年,多交换机系统由工程师勒罗伊B 菲尔曼发明,使电话取得商业成功,用户在1890年达到250000。 直到1894年,贝尔原批专利过期,贝尔电话公司在市场上有一个虚拟的垄断。他们已经成功侵权投诉反对至少600竞争者。该公司曾在1896年,刚刚在中央交易所推出了电源的“普通电池”制度。在那之前,一个人有手摇电话以提供足够的电力呼叫。一个连接可能仍然只能在给予该人的名义下提出要求达到一个电话接线员。这是强改变的原因。 强很快成为贝尔的强大竞争者。他在1901年引进了一个桌面拨号模型,这个模型在设计方面比贝尔的模型更加清晰。在1902年,他引进了一个带有磁盘拨号的墙面电话,这次与实际指孔,仍然只有170度左右在磁盘周围。到1905年,一个“长距离”手指孔已经被增加了。最后一个强的知名模型是在1907年。强的专利大概过期于1914年,之后他或他的公司再也没有听到过。直到1919年贝尔引进了拨号系统。当他们这样做,在拨号盘的周围手指孔被充分扩展了。 强发明的拨号系统直到1922年进入像纽约一样的大城市才成为主流。但是一旦作为规规范被确立,直到70年代它仍然是主要的电话技术。后按键式拨号在1963年被推出之后,强发明的最初的手指拨号系统作为“旋转的拨号系统”而知名。这是强怎样“让你的手指拨号”的。 埃姆斯椅LCW和DCW 1947 这些带有复合曲线座位,靠背和橡胶防震装置的成型胶合板椅是由查尔斯埃姆斯设计,在赫曼米勒家具公司生产的。 这个原始的概念是被查尔斯埃姆斯(1907—1978)和埃罗沙里宁(1910—1961)在1940年合作构想出来的。在1937年,埃姆斯成为克兰布鲁克学院实验设计部门的领头人,和沙里宁一起工作调查材料和家具。在这些努力下,埃姆斯发明了分成薄片和成型胶合板夹板,被称作埃姆斯夹板,在1941年收到了来自美国海军5000人的订单。查尔斯和他的妻子雷在他们威尼斯,钙的工作室及工厂和埃文斯产品公司的生产厂家一起生产了这批订单。 在1941年现代艺术博物馆,艾略特诺伊斯组织了一场比赛用以发现对现代生活富有想象力的设计师。奖项颁发给了埃姆斯和沙里宁他们的椅子和存储碎片,由包括埃德加考夫曼,大都会艺术博物馆的阿尔弗雷德,艾略特诺伊斯,马尔塞布鲁尔,弗兰克帕里什和建筑师爱德华达雷尔斯通的陪审团裁决。 这些椅子在1946年的现代艺术展览博物馆被展出,查尔斯埃姆斯设计的新的家具。当时,椅子只有三条腿,稳定性问题气馁了大规模生产。 早期的LCW(低木椅)和DWC(就餐木椅)设计有四条木腿在1946年第一次被埃文斯产品公司(埃姆斯的战时雇主)生产出来,被赫曼米勒家具公司分配。这些工具1946年被乔治纳尔逊为赫曼米勒购买,在1949年接手制造权。后来金属脚的愿景在1951年制作,包括LCW(低金属椅)和DWC(就餐金属椅)模型。配套的餐饮和咖啡桌也产生。这条线一直

外文翻译

Load and Ultimate Moment of Prestressed Concrete Action Under Overload-Cracking Load It has been shown that a variation in the external load acting on a prestressed beam results in a change in the location of the pressure line for beams in the elastic range.This is a fundamental principle of prestressed construction.In a normal prestressed beam,this shift in the location of the pressure line continues at a relatively uniform rate,as the external load is increased,to the point where cracks develop in the tension fiber.After the cracking load has been exceeded,the rate of movement in the pressure line decreases as additional load is applied,and a significant increase in the stress in the prestressing tendon and the resultant concrete force begins to take place.This change in the action of the internal moment continues until all movement of the pressure line ceases.The moment caused by loads that are applied thereafter is offset entirely by a corresponding and proportional change in the internal forces,just as in reinforced-concrete construction.This fact,that the load in the elastic range and the plastic range is carried by actions that are fundamentally different,is very significant and renders strength computations essential for all designs in order to ensure that adequate safety factors exist.This is true even though the stresses in the elastic range may conform to a recognized elastic design criterion. It should be noted that the load deflection curve is close to a straight line up to the cracking load and that the curve becomes progressively more curved as the load is increased above the cracking load.The curvature of the load-deflection curve for loads over the cracking load is due to the change in the basic internal resisting moment action that counteracts the applied loads,as described above,as well as to plastic strains that begin to take place in the steel and the concrete when stressed to high levels. In some structures it may be essential that the flexural members remain crack free even under significant overloads.This may be due to the structures’being exposed to exceptionally corrosive atmospheres during their useful life.In designing prestressed members to be used in special structures of this type,it may be necessary to compute the load that causes cracking of the tensile flange,in order to ensure that adequate safety against cracking is provided by the design.The computation of the moment that will cause cracking is also necessary to ensure compliance with some design criteria. Many tests have demonstrated that the load-deflection curves of prestressed beams are approximately linear up to and slightly in excess of the load that causes the first cracks in the tensile flange.(The linearity is a function of the rate at which the load is applied.)For this reason,normal elastic-design relationships can be used in computing the cracking load by simply determining the load that results in a net tensile stress in the tensile flange(prestress minus the effects of the applied loads)that is equal to the tensile strength of the concrete.It is customary to assume that the flexural tensile strength of the concrete is equal to the modulus of rupture of the

建筑类外文文献及中文翻译

forced concrete structure reinforced with an overviewRein Since the reform and opening up, with the national economy's rapid and sustained development of a reinforced concrete structure built, reinforced with the development of technology has been great. Therefore, to promote the use of advanced technology reinforced connecting to improve project quality and speed up the pace of construction, improve labor productivity, reduce costs, and is of great significance. Reinforced steel bars connecting technologies can be divided into two broad categories linking welding machinery and steel. There are six types of welding steel welding methods, and some apply to the prefabricated plant, and some apply to the construction site, some of both apply. There are three types of machinery commonly used reinforcement linking method primarily applicable to the construction site. Ways has its own characteristics and different application, and in the continuous development and improvement. In actual production, should be based on specific conditions of work, working environment and technical requirements, the choice of suitable methods to achieve the best overall efficiency. 1、steel mechanical link 1.1 radial squeeze link Will be a steel sleeve in two sets to the highly-reinforced Department with superhigh pressure hydraulic equipment (squeeze tongs) along steel sleeve radial squeeze steel casing, in squeezing out tongs squeeze pressure role of a steel sleeve plasticity deformation closely integrated with reinforced through reinforced steel sleeve and Wang Liang's Position will be two solid steel bars linked Characteristic: Connect intensity to be high, performance reliable, can bear high stress draw and pigeonhole the load and tired load repeatedly.

工业设计外文翻译

Interaction design Moggridge Bill Interaction design,Page 1-15 USA Art Press, 2008 Interaction design (IxD) is the study of devices with which a user can interact, in particular computer users. The practice typically centers on "embedding information technology into the ambient social complexities of the physical world."[1] It can also apply to other types of non-electronic products and services, and even organizations. Interaction design defines the behavior (the "interaction") of an artifact or system in response to its users. Malcolm McCullough has written, "As a consequence of pervasive computing, interaction design is poised to become one of the main liberal arts of the twenty-first century." Certain basic principles of cognitive psychology provide grounding for interaction design. These include mental models, mapping, interface metaphors, and affordances. Many of these are laid out in Donald Norman's influential book The Psychology of Everyday Things. As technologies are often overly complex for their intended target audience, interaction design aims to minimize the learning curve and to increase accuracy and efficiency of a task without diminishing usefulness. The objective is to reduce frustration and increase user productivity and satisfaction. Interaction design attempts to improve the usability and experience of the product, by first researching and understanding certain users' needs and then designing to meet and exceed them. (Figuring out who needs to use it, and how those people would like to use it.) Only by involving users who will use a product or system on a regular basis will designers be able to properly tailor and maximize usability. Involving real users, designers gain the ability to better understand user goals and experiences. (see also: User-centered design) There are also positive side effects which include enhanced system capability awareness and user ownership. It is important that the user be aware of system capabilities from an early stage so that expectations regarding functionality are both realistic and properly understood. Also, users who have been active participants in a product's development are more likely to feel a sense of ownership, thus increasing overall satisfa. Instructional design is a goal-oriented, user-centric approach to creating training and education software or written materials. Interaction design and instructional design both rely on cognitive psychology theories to focus on how users will interact with software. They both take an in-depth approach to analyzing the user's needs and goals. A needs analysis is often performed in both disciplines. Both, approach the design from the user's perspective. Both, involve gathering feedback from users, and making revisions until the product or service has been found to be effective. (Summative / formative evaluations) In many ways, instructional

外文翻译

Journal of Industrial Textiles https://www.360docs.net/doc/8814741847.html,/ Optimization of Parameters for the Production of Needlepunched Nonwoven Geotextiles Amit Rawal, Subhash Anand and Tahir Shah 2008 37: 341Journal of Industrial Textiles DOI: 10.1177/1528083707081594 The online version of this article can be found at: https://www.360docs.net/doc/8814741847.html,/content/37/4/341 Published by: https://www.360docs.net/doc/8814741847.html, can be found at:Journal of Industrial TextilesAdditional services and information for https://www.360docs.net/doc/8814741847.html,/cgi/alertsEmail Alerts: https://www.360docs.net/doc/8814741847.html,/subscriptionsSubscriptions: https://www.360docs.net/doc/8814741847.html,/journalsReprints.navReprints: https://www.360docs.net/doc/8814741847.html,/journalsPermissions.navPermissions: https://www.360docs.net/doc/8814741847.html,/content/37/4/341.refs.htmlCitations: - Mar 28, 2008Version of Record >>

建筑-外文翻译

外文文献: Risk Analysis of the International Construction Project By: Paul Stanford Kupakuwana Cost Engineering Vol. 51/No. 9 September 2009 ABSTRACT This analysis used a case study methodology to analyse the issues surrounding the partial collapse of the roof of a building housing the headquarters of the Standards Association of Zimbabwe (SAZ). In particular, it examined the prior roles played by the team of construction professionals. The analysis revealed that the SAZ’s traditional construction project was generally characterized by high risk. There was a clear indication of the failure of a contractor and architects in preventing and/or mitigating potential construction problems as alleged by the plaintiff. It was reasonable to conclude that between them the defects should have been detected earlier and rectified in good time before the partial roof failure. It appeared justified for the plaintiff to have brought a negligence claim against both the contractor and the architects. The risk analysis facilitated, through its multi-dimensional approach to a critical examination of a construction problem, the identification of an effective risk management strategy for future construction projects. It further served to emphasize the point that clients are becoming more demanding, more discerning, and less willing to accept risk without recompense. Clients do not want surprise, and are more likely to engage in litigation when things go wrong. KEY WORDS:Arbitration, claims, construction, contracts, litigation, project and risk The structural design of the reinforced concrete elements was done by consulting engineers Knight Piesold (KP). Quantity surveying services were provided by Hawkins, Leshnick & Bath (HLB). The contract was awarded to Central African Building Corporation (CABCO) who was also responsible for the provision of a specialist roof structure using patented “gang nail” roof

市场类中英文对照翻译

原文来源:李海宏《Marketing Customer Satisfaction》[A].2012中国旅游分销高峰论坛.[C].上海 Marketing Customer Satisfaction 顾客满意策略与顾客满意营销 Since the 20th century, since the late eighties, the customer satisfaction strategy is increasingly becoming business has more customers share the overall business competitive advantage means. 自20世纪八十年代末以来,顾客满意战略已日益成为各国企业占有更多的顾客份额,获得竞争优势的整体经营手段。 First, customer satisfaction strategy is to get a modern enterprise customers, "money votes" magic weapon 一、顾客满意策略是现代企业获得顾客“货币选票”的法宝 With the changing times, the great abundance of material wealth of society, customers in the main --- consumer demand across the material has a lack of time, the number of times the pursuit, the pursuit of quality time to the eighties of the 20th century entered the era of the end consumer sentiment. In China, with rapid economic development, we have rapidly beyond the physical absence of the times, the pursuit of the number of times and even the pursuit of quality and age of emotions today gradually into the consumer era. Spending time in the emotion, the company's similar products have already reached the same time, homogeneous, with the energy, the same price, consumers are no longer pursue the quality, functionality and price, but the comfort, convenience, safety, comfort, speed, jump action, environmental protection, clean, happy,

工业设计产品设计中英文对照外文翻译文献

(文档含英文原文和中文翻译) 中英文翻译原文:

DESIGN and ENVIRONMENT Product design is the principal part and kernel of industrial design. Product design gives uses pleasure. A good design can bring hope and create new lifestyle to human. In spscificity,products are only outcomes of factory such as mechanical and electrical products,costume and so on.In generality,anything,whatever it is tangibile or intangible,that can be provided for a market,can be weighed with value by customers, and can satisfy a need or desire,can be entiled as products. Innovative design has come into human life. It makes product looking brand-new and brings new aesthetic feeling and attraction that are different from traditional products. Enterprose tend to renovate idea of product design because of change of consumer's lifestyle , emphasis on individuation and self-expression,market competition and requirement of individuation of product. Product design includes factors of society ,economy, techology and leterae humaniores. Tasks of product design includes styling, color, face processing and selection of material and optimization of human-machine interface. Design is a kind of thinking of lifestyle.Product and design conception can guide human lifestyle . In reverse , lifestyle also manipulates orientation and development of product from thinking layer.

外文翻译中文版(完整版)

毕业论文外文文献翻译 毕业设计(论文)题目关于企业内部环境绩效审计的研究翻译题目最高审计机关的环境审计活动 学院会计学院 专业会计学 姓名张军芳 班级09020615 学号09027927 指导教师何瑞雄

最高审计机关的环境审计活动 1最高审计机关越来越多的活跃在环境审计领域。特别是1993-1996年期间,工作组已检测到环境审计活动坚定的数量增长。首先,越来越多的最高审计机关已经活跃在这个领域。其次是积极的最高审计机关,甚至变得更加活跃:他们分配较大部分的审计资源给这类工作,同时出版更多环保审计报告。表1显示了平均数字。然而,这里是机构间差异较大。例如,环境报告的数量变化,每个审计机关从1到36份报告不等。 1996-1999年期间,结果是不那么容易诠释。第一,活跃在环境审计领域的最高审计机关数量并没有太大变化。“活性基团”的组成没有保持相同的:一些最高审计机关进入,而其他最高审计机关离开了团队。环境审计花费的时间量略有增加。二,但是,审计报告数量略有下降,1996年和1999年之间。这些数字可能反映了从量到质的转变。这个信号解释了在过去三年从规律性审计到绩效审计的转变(1994-1996年,20%的规律性审计和44%绩效审计;1997-1999:16%规律性审计和绩效审计54%)。在一般情况下,绩效审计需要更多的资源。我们必须认识到审计的范围可能急剧变化。在将来,再将来开发一些其他方式去测算人们工作量而不是计算通过花费的时间和发表的报告会是很有趣的。 在2000年,有62个响应了最高审计机关并向工作组提供了更详细的关于他们自1997年以来公布的工作信息。在1997-1999年,这62个最高审计机关公布的560个环境审计报告。当然,这些报告反映了一个庞大的身躯,可用于其他机构的经验。环境审计报告的参考书目可在网站上的最高审计机关国际组织的工作组看到。这里这个信息是用来给最高审计机关的审计工作的内容更多一些洞察。 自1997年以来,少数环境审计是规律性审计(560篇报告中有87篇,占16%)。大多数审计绩效审计(560篇报告中有304篇,占54%),或组合的规律性和绩效审计(560篇报告中有169篇,占30%)。如前文所述,绩效审计是一个广泛的概念。在实践中,绩效审计往往集中于环保计划的实施(560篇报告中有264篇,占47%),符合国家环保法律,法规的,由政府部门,部委和/或其他机构的任务给访问(560篇报告中有212篇,占38%)。此外,审计经常被列入政府的环境管理系统(560篇报告中有156篇,占28%)。下面的元素得到了关注审计报告:影响或影响现有的国家环境计划非环保项目对环境的影响;环境政策;由政府遵守国际义务和承诺的10%至20%。许多绩效审计包括以上提到的要素之一。 1本文译自:S. Van Leeuwen.(2004).’’Developments in Environmental Auditing by Supreme Audit Institutions’’ Environmental Management Vol. 33, No. 2, pp. 163–1721

外文翻译建筑学

芬兰建筑主要因两点而闻名实用而直接的现代主义和一种同自然之间的虚构的关系。从阿尔瓦·阿尔托和他同时代——包括埃里克·布吕格曼和保利·布卢姆斯泰特 . 在内——的那些设计了年前的芬兰现代建筑作品的建筑师开始就是如此。阿尔托在年代的设计特别是完成于年的帕伊米奥疗养院布吕格曼设计的私人住宅和图尔库的公寓区以及布卢姆斯泰特的教堂设计都是芬兰现代建筑早期阶段的标志。在这之后现代主义运动的主流和分支总是成为芬兰建筑学习的对象。如此忠诚于现代主义的原因可以归结到芬兰自年独立以来的社会发展以及北欧人一贯的建筑和设计方向。北部的地理位置和文化在北欧的多种现代主义中建筑是与众多北部 欧洲的文化特性交织在一起的。起决定性的因素是气候和自然环境 同时还有从路德教而来、体现在北欧福利国家的一种共有的精神。这里值得一提的是在当地民众与自然之间的关系形成的过程中有一个关键因素——“自由信步”的理念简而言之即在一定限度内每个人都有权利进入到自然环境及其所赋予的一切中去。这一传统在那些居住环境与自然紧密相联的地方广为人知在北欧国家更是根深蒂固。波罗的海地区的自然环境十分富足、多样且尺度较小。内陆中不计其数的湖面形成了广阔的水路。芬兰被称为“千岛之国”。实际上可以说芬兰的自然环境充满了各种独特的场所。我们没有一望无际的海岸沙滩或巨大的高差但是我们拥有河、湖和群岛。多样且无所不在的水陆交替为芬兰的自然环境提供了一种韵律。这种韵律既是视觉上的也是精神上的。此外四季的变换——温暖明亮

的夏季和寒冷多雪的冬季——强化了景观的多变对自然空间的应用有着显著影响。关于芬兰建筑前文所述都与芬兰人所认知的好建筑密切相关。在这里成为好建筑的关键因素是同地段或场所的联系 及其空间体验。当代芬兰建筑中的自然和现代主义尤哈那·拉赫蒂孙凌波译: . , . , . ' , , ' , ' , , . , , . Finland' , . , , , . ' , , " ", , , , . , , , . , , . Finland . , . . , , . . . , , , , . Finland. , , . , , . ’ . , , . , . , 首先成为好建筑要尊重地段及其历史无论它是在自然环境里还是在城市之中。以阿尔瓦·阿尔托为代表的年代的芬兰建筑师一贯坚持在项目进程中对地段上的树木加以保护。这是让自然成为建筑院落一部分的方式之一。在这个时代区域划分成为城市规划的一部

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