Ostwald ripening 法是什么?

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Ostwald ripening 法是什么?

Ostwald ripening 法是什么?
Ostwald ripening 法是什么?

Ostwald ripening 法是什么?
Ostwald ripening是一种材料生长的机理,简单点说就是材料从分子阶段开始,首先形成一定尺寸的晶核,然后所有的分子都依附于晶核生长,这个阶段不会再形成新的晶核了,只是晶核生长的越来越大,
形成单晶结构的方式有几种,Ostwald ripening是最经典的一种,“从液态转变为固态的过程首先要成核,然后生长,这个过程叫晶粒的成核长大.晶粒内分子、原子都是有规则地排列的,所以一个晶粒就是单晶”.同时最近几年,Banfiled又提出了一种新的晶体生长机制也能形成单晶结构,oriented attachment,多个取向不一致的单晶纳米颗,通过粒子的旋转,使得晶格取向一致,向后通过定向附着生长(oreinted attachment)使这些小单晶生长成为一个大单晶,当然定向附着的过程出难免会出现一些位错和缺陷,这种生长机理形成的单晶的特点同Ostwald ripening不同,OR形成的单晶大多是规则的,给材料本身晶体结构相关,而OA形成的单晶结构在形貌上则没有限制,任何形状和结构的单晶材料都能通过此机理形成.还有,Alivisatos最近报道的Kirkendall Effect 也能形成单晶结构,在其论文中报道了通过这种机理形成的直径只有几十个纳米的单晶空心球,这种结构以传统的Ostwald ripening来看貌似是不可实现的,但通过别的生长机理就能成为现实.
Ostwald发生的过程包括小于一个临界尺寸的粒子的溶解,然后质量转移到大于这个临界尺寸的粒子上.
Ostwald过程不同于dissolution-recrystallization过程,因为它强调的是小粒子的溶解,大粒子依靠摄取小粒子的质量进行生长.Ostwald 过程发生的驱动力是粒子相总表面积的降低产生的总界面自由能的降低.

Ostwald ripening 法是什么? 英语翻译Abstract:The well-known physical phenomenon Ostwald ripening in crystal growth has been widelyemployed in template-free fabrication of hollow inorganic nanostructures in recent years.Nevertheless,allreported works so far are limited only ostwald solubility coefficients是什么意思 英语翻译Monitoring the Chemical and Textural Changes During Ripening of Iranian White Cheese Made with Different Concentrations of Starter. 液体粘滞系数的测定实验1.为什么水与酒精的体积必须相同,而且实验时均保持竖直2.Ostwald粘滞计在测量时要放在水槽中3.测量之前为什么需要润湿Ostwald粘滞计4.血液粘滞系数对人体的影响兄 Variety:Chardonnay.Origin:El Triángulo Vineyard,Casablanca Valley.Soil:Colluvial soil of sedimentary with great maritime influence creating foggy conditions,which act moderating high temperatures and thus allowing slower-paced ripening.Spring skies 英语翻译3.6.Sensory analysisThe mean grades for flavour intensity and flavour and texture acceptability of cheeses at 60,120 and 180 days of ripening are shown in Table 3.Generally,the raw milk cheese received higher scores than pasteurised milk 英语翻译1.He stretched out his arm and said,“Grandpa,let me take you across.”2.His fingers were strained from cigarettes and he chewed the inside of his lips a lot.3.It good to smell the scent of ripening rice in November. 各位英语达人,小弟遇到一个句子,百思而不得其解,望各位帮忙翻译并分析句子结构The trickled ethylene gas process of tomato ripening consists of exposing the tomatoes to a low concentration of ethylene gas under controlled there is a slight easing of tension,a mellowing of character like the ripening of fruit or the mellowing of good wine,and the gradual acquiring of a more tolerant,more cynical and at the same time a kindlier view of life;这句话怎么分析语法?