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Jian Zhou

    Molecular dynamics simulation of grain boundary migration
    Fundamentals of military law
    Fundamentals of Military Law
    500 basic Chinese characters. A speedy elementary course
    • 西方人学汉语,感到最困难的地方,莫过于汉字了。汉字难认,难读,难写,难记。对于习惯了拼音文字的西方初学者来说,汉语的方块字,无异于天书,“每一个字都像是一幅神秘的图画”。汉字难的问题主要有两大原因:一是数量大,汉字总共有五万多个,低限度的常用字也有三四千;二是笔画多,简化之后,常用字平均仍有八笔之多。对于母语为拼音文字的初学者来说,还要加上一条字母拼音文字与方块表意文字有巨大差异,汉字字形与读音常常不能直接挂钩。例如“友、邓、权、圣、反、支、戏、对、发、叙”等字中都有“又”字,读音却无一相似。人们多认为汉字是表意文字,其实以形声字为主的汉字常常既表意也表声,故俗谚有“读字读半边,不会错上天”之说。不过汉字演变至今,其形、音、义之间往往已缺乏关联,有关联的也不够明显,需要在已经掌握了大量汉字的基础上,经过对比、揣摩才能了解,初学者常常只能“一个图形一个图形地死记硬背”,学习汉字的效率很低,书写时常常出错,有时还会创造出一些“很可笑的”错字来。应当看到,虽然同是汉字的初学者,中国小学生与外国学生有着很大的差异。中国孩子在入学之前已经掌握了大量的汉语词汇和语句,他们通常对所学生字的读音及字义(或词义)已经相当熟悉了。有了这种预备知识,学习汉字的过程便简化为建立字音(已知)、字义(已知)与字形(未知)三者之间的对应关系,学起来自然事半功倍了。外国学生对生字的音、形、义都不熟悉,对三者的掌握是同步进行的,无法“对号人座”,再加上他们缺乏使用汉语的大环境,更没有从小就接受字形记忆方面的长期训练,因此难怪他们要把学汉字视为畏途了。但外国学生也有优势,他们一般都是成年人了,有比较丰富的综合文化知识和较强的认知领悟能力。 《外国人汉字速成》试图采用外国学生喜闻乐见的方式,在较短的时间内突击教会500个最基本的汉字。学生有了基础,以后再学新字就会感到越来越容易,因为他们可以运用部件、偏旁、部首、谐音等知识来理解、记忆和领悟汉字形、音、义之间的关联了。例如学生如果掌握了“人、百”这些部件(字)的含义,再讲宿舍的“宿”字,就轻而易举了。 我们认为应当调动一切认知手段——既包括逻辑思维的也包括形象思维的——来建立初学者大脑中的汉字库。一切视觉的、联想的、比较的、分析的、谐音的、荒诞的都可以采用。最有效的办法是在讲解每一个字时都给学生一点儿提示或联想。 中国人习惯用词来界定字,如他叫章平,文章的章,和平的平。字与词的关系密不可分。《外国人汉字速成》介绍了与所学字有关的常用词、词组、成语和短语,既有字头词也有字尾词、字中词,总数达3000余条,涵盖了中国对外汉语教学学会、汉语水平等级标准研究小组在1988年11月公布的《词汇等级大纲》中相当大一部分甲级词和乙级词。这些词汇在教学中可以帮助学生全面地理解汉字的意思和用法,并不要求他们都掌握。

      500 basic Chinese characters. A speedy elementary course
    • Fundamentals of Military Law

      A Chinese Perspective

      • 592 Seiten
      • 21 Lesestunden

      Focusing on military law, this book offers a thorough analysis of its foundational principles and theories, reimagining the theoretical framework. It introduces innovative concepts such as "core military law" and "international military law," marking a significant development in both China and globally. Aimed at legal scholars and military lawyers, it provides a fresh perspective for studying military law, making it a valuable resource for those in the field.

      Fundamentals of Military Law
    • The book makes a comprehensive analysis of the basic principles and theories of military law, restructuring the theoretic framework of military law. It also puts forwards the new concepts of “core military law” and “international military law” for the first time in China, and even the world. The book could help legal scholars and lawyers, especially military lawyers and research fellows in military law, to have a new approach to study military law.

      Fundamentals of military law
    • Migration of tilt grain boundaries (GBs) in aluminum has been simulated across a wide temperature range and various driving forces. It is found that GBs migrate through either a diffusionless or diffusional mechanism, depending on the conditions. The diffusionless mechanism is characterized by GB dislocation glide, which aligns with previously reported mechanisms involving collective atom group motion, four-atom shuffling, and glide of primary/secondary GB dislocations. This dislocation glide serves as a generalized mechanism for these processes. Conversely, the diffusional mechanism is observed in high-angle GBs at elevated temperatures with a small driving force of several MPa, where GB migration is governed by GB diffusion. The study discusses how structural constraints, temperature, GB misorientation, and driving force magnitude influence the activation of each mechanism and the specific GB migration behaviors. Two GB migration mechanism maps for polycrystals are proposed, effectively explaining many prior contradictory findings in experiments and simulations. Additionally, GB mobilities are evaluated at high temperatures, revealing that high-angle GBs migrate faster than low-angle ones, with maximum mobility occurring around 40° misorientation. The mobility of a Σ7 GB approaches the maximum experimental value seen in ultra-high-purity bicrystals.

      Molecular dynamics simulation of grain boundary migration