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1.
The experiment in which a candle is burned inside an inverted vessel partially immersed in water has a history of more than
2,200 years, but even nowadays it is common that students and teachers relate the change in volume of the enclosed air to
its oxygen content. Contrary to what many people think, Lavoisier concluded that any change in volume in this experiment is
negligible; moreover, the explanation relating oxygen consumption in the air with its change in volume is known to be wrong.
In this work we briefly review the history behind the candle experiment and its relationship with some typical erroneous explanations.
One of the key factors behind Lavoisier’s success was the use of experiments carefully designed to test different hypotheses.
Following these steps, we performed several closed volume experiments where the candle wick was replaced by a capillary stainless
steel cylinder supported and heated by a nichrome filament connected to an external power supply. Our recorded experiments
are displayed as web pages, designed with the purpose that the reader can easily visualize and analyze modern versions of
Lavoisier’s experiments. These experiments clearly show an initial phase of complete combustion, followed by a phase of incomplete
combustion with elemental carbon or soot rising to the top of the vessel, and a final phase where the hot artificial wick
only evaporates a white steam of wax that cannot ignite because no oxygen is left in the closed atmosphere. After either a
complete or incomplete combustion of the oxygen, our experiments show that the final gas volume is nearly equal to the initial
air volume. 相似文献
2.
The concept of metacognition refers to one’s knowledge and control of one’s own cognitive system. However, despite being widely
used, this concept is confusing because of several reasons. First, sometimes it is not at all clear what is cognitive and
what is metacognitive. Second, researchers often use the same term, namely, “metacognition” even when they refer to very different
aspects of this complex concept. Alternatively, researchers may use different terms to indicate the same metacognitive elements.
Another foggy matter is the interrelationships among the various components of metacognition discussed in the literature.
This conceptual confusion regarding the concept of metacognition and its sub-components calls for in-depth theoretical and
conceptual clarifications. The goal of this article is to portray a detailed example of a conceptual analysis of meta-strategic
knowledge (MSK) which is one specific component of metacognition. This specific example is used to draw a general model for
conceptual analyses of additional metacognitive components. The approach suggested here is to begin with a clear definition
of the target sub component of metacognition, followed by a systematic examination of this sub component according to several
dimensions that are relevant to metacognition in general and to that sub component in particular. The examination should include
an analysis of how the details of the definition of the target sub-component refer to: (a) general theoretical metacognitive
issues raised by prominent scholars; (b) definitions formulated and issues raised by other researchers who have investigated
the same (or a similar) sub-component and, (c) empirical findings pertaining to that sub-component. Finally, it should be
noted that since metacognition is a relational rather than a definite concept it is important to situate the context within
which the conceptual analysis takes place. 相似文献
3.
This article has no direct link with academics, children, students or those who teach: I severed almost all such connections several years ago. It describes the rewards and challenges of leading a reminiscence group of elderly people, all of whom suffer some level of memory loss and/or severe physical disability; most are wheelchair-bound. It contains examples of their autobiographical talk which I recorded separately from group meetings and transcribed, exclusively for the satisfaction of each individual concerned. Ours is not a society which cherishes its aged members. What becomes of their identity? Who are they now? They are, of course, people – as interesting as those in our classrooms. They too need to know their own worth. 相似文献
4.
张威 《中国教育研究与创新》2006,3(11):145-150
天保房地产开发公司根植于天津滨海新区。依托控股公司带来的资源优势，基于滨海新区列入国家发展战略部署的背景，在近年来取得了迅速的发展。但是随着国家一系列政策的出台，中国的房地产行业面临着一次大的重新洗牌过程，同时企业内部仍然存在着制度缺陷、管理不规范、流程不清晰、人员激励不足等各方面的问题，所以，天保房地产公司在面临着滨海新区良好发展机遇的同时，也面临着很大的挑战。如何在机遇与挑战并存的环境中，认真分析和评估企业的外部环境及内部资源与能力的优劣势，对企业内部的资源与能力进行积累与培养，制定相应的竞争与发展战略，引导企业的健康长远发展具有一定的必要性与迫切性。
本文从竞争战略的角度，综合分析天保房地产开发公司所面临的外部环境和内部条件，研究探讨天保房地产开发公司的发展战略框架，包括战略的指导思想、战略定位、战略目标及相应的实施措施，以期实现天保房地产开发公司的发展愿景和核心价值。 相似文献
5.
张红旗 《廊坊师范学院学报》2010,(3):80-83
公推直选乡镇长与乡镇党委书记出现的时间、发展现状与趋势、制度依据、选举成本,以及乡镇长与乡镇党委书记在乡镇政权中的作用有明显的不同。在我们看来,直接选举乡镇党委书记,发展的空间更广阔,对乡镇民主建设与乡镇政府职能转型所起的作用更大。 相似文献
6.
徐振芳 《中学英语之友(高二版)》2008,(Z2)
秦二世时,丞相赵高野心勃勃,日夜盘算着要篡夺皇位。可朝中大臣有多少人能听他摆布,有多少人反对他,他心中没底。于是,他想了一个办法,准备试一试自己的威信,同时也可以摸清敢于反对他的人。 相似文献
7.
Easy Phonics带你学习自然拼读,让你学会字母的发音规律,正确地拼读单词。本期让我们继续来看看、读读、写写重读音节中包含字母a的单词,区分它们读短音short a-/e/,还是长音long a-/ei/。 相似文献
8.
Easy Phonics栏目带你轻松地学习自然拼读!在读读、听听、拼拼和玩游戏中,你将了解字母的发音规律,并正确地拼读单词。这一期,我们来学习元音字母a的短音(short a)和长音(long a). 相似文献
9.
从前,有一句话,叫做"吃得苦中苦,方为人上人".这句话被认为动机不纯,怎么可以做"人上人"呢?其实,对于"人上人"可以作不同的理解,一种理解是"骑在人民头上,作威作福",这种"人上人"当然不好;但也可以解释为比别人做更多的贡献,吃更多的苦,经过更多的挫折与困难而比一般人更成熟、更坚强,更知道怎么做人.实际上,对这句话应是作后一种理解的,因为这种"人上人"是与"苦中苦"联系在一起的. 相似文献
10.
影响物流中心选址的因素及一种选址方法 总被引：2，自引：0，他引：2
文章论述了影响物流中心选址的七大因素,建议采用模糊评判的方法,该方法克服了传统选址方法的片面性、局限性和计算的复杂性,可对多种可供选择的方案做出明确的排序,使选址问题变得更加合理、科学与全面,更加反映客观实际. 相似文献
11.
Zaidman-Zait A 《Journal of deaf studies and deaf education》2007,12(2):221-241
This study aimed to describe and categorize the attributes that parents of young children with cochlear implants (CIs) consider as facilitating their parental coping experience. I interviewed 15 hearing mothers and 13 hearing fathers (including 12 married couples) whose children had CIs, using the critical incident technique that asked parents to describe significant incidents (observable behaviors, thoughts, feelings) that facilitated their parenting experience. A total of 430 critical incidents were documented and sorted into 20 categories. Further analyses supported the suggested categorical system's validity and reliability. Results indicated various sources of influence on parents' coping experience, associated with social contextual aspects (e.g., professionals' support, sharing experience with others, family's/friends' consistent involvement, intervention services), with the parent himself or herself (e.g., taking action, personal resources, incorporating deafness into daily life), and with the child (e.g., child characteristics, identifying progress and success). The current research substantiates the soundness of implementing early intervention models such as the developmental system model (Guralnick, 2001) and the support approach to early intervention (McWilliam & Scott, 2001), which coincide with ecological theory and recognize that families need various combinations of resources, social support, information, and services to help them address the stressors associated with parenting in general and parenting a child with special needs in particular. 相似文献
12.
W. R. Morford 《Quest (Human Kinetics)》2013,65(1):88-93
Physical education has a rich tradition of concern for the development of fully functioning individuals, but this tradition is in danger of being marginalized by the dominant technocratic and competitive structures of today's physical education. The purpose of this paper, in seeking to readdress the value of the experiential dimensions of sport, is to provide the instructor with insight into a specific domain of sport—challenging outdoor activity, or risk sport—that holds particular value for Bain's (1988) alternative approach for humanistic physical education. Employing the model of risk-sport involvement (Robinson, 1992) as an analytical framework, the paper attempts to promote an understanding of the complex nature of the risk-sport experience and the potential value such experiences hold for personal growth, meaningful social interaction, and social change. 相似文献
13.
张昭兵 《南京师范大学文学院学报》2009,(4):37-44
本文从毕飞宇小说中一再出现的镜、钟、影和胡琴的意向入手,考察毕飞宇小说的叙述人称、叙述速度、叙述结构和叙述意图。深入阐释＂我＂与＂他＂的分离与揉合,＂快＂与＂慢＂的交替与演变,＂是＂与＂非＂的分明与模糊,＂语言＂与＂沉默＂的相反而相成。 相似文献
14.
Penny Crawley 《International journal for the advancement of counseling》1984,7(4):261-265
The problems which arise between a disabled or chronically ill nurse and her nursing colleagues are explored. Ways of recognising and resolving some of the difficulties are suggested. Recommendations are made that the findings should be incorporated into the future training of nurses, and that sufficient staff Counsellors should be appointed to Hospitals to enable the nurses, both disabled and nondisabled to deal creatively with the stress which affects their professional and personal relationships. 相似文献
15.
This article reports on a case study where a professional musician was assigned to a primary school as mentor in a project where 14 primary-aged children, with their teacher's direction, were involved in the composition of a piece of music that would act as prologue to the school's major production. The researchers were interested in aspects of the composition project that appeared to develop student's compositional skills and motivation and how the mentor might exercise his role in the composition project alongside the teacher, who was the school's music specialist. A range of data was analyzed: classroom observations, emails, questionnaires, and one-on-one and focus-group interviews. Findings suggested that the involvement of the mentor was well received by the pupils and that the mentor and teacher complemented one another in their enactment of both pedagogical and compositional roles. Students enjoyed a high sense of success in the production of their composition. Student learning were highly variable and a range of activities and processes was identified by students as contributing to their learning. 相似文献
16.
吴佳颖 《英语大王(小学)》2014,(3):34-34
In spring, it＇s always warm and sunny. People like to go outing. ff＇s sunny today. The Blacks have a picnic in a park. There are many big trees and flowers in the park. They take lots of food with them. There is fruit, drinks, bread and so on. 相似文献
17.
Richard Balkin 《Interchange》1973,4(1):79-87
The first step in publishing a college textbook is usually the submission of a proposal. Currently, textbook publishers are cutting back the number of books they are contracting, but over-the-transom proposals continue to flood editors' desks. Very few proposals are properly prepared since few would-be authors are aware of the precise information a publisher needs. This article suggests both guidelines for a good proposal, as well as some additional hints for textbook publication.
Bobbs-Merrill Co.
The author wishes to express his gratitude to the following persons for their helpful suggestions and comments: Wm. H. Y. Hackett, Jr., Edward McLeroy, Philip D. Jones, Gardner Spungin, Ceil Smith, Andrew Effart, Lloyd Scott, and Georgia West-Balkin. This article is the first chapter in a forthcoming book,A Handbook to College Publishing, for which the author is currently seeking a contract himself. 相似文献
Résumé La première phase lors de la publication d'un manuel de collège est normalement de présenter une soumission. Pour le présent, les éditeurs de manuels sont en train de réduire le nombre de manuels qu'ils entreprennent de publier mais les soumissions spontanées continuent d'inonder les bureaux des éditeurs. Très peu de soumissions sont préparées correctement car peu d'auteurs prétendus sont au courant des renseignements précis dont un éditeur a besoin. Le présent article suggère des recommandations pour présenter des soumissions valables ainsi que des conseils additionnels sur la publication de manuels.
Bobbs-Merrill Co.
The author wishes to express his gratitude to the following persons for their helpful suggestions and comments: Wm. H. Y. Hackett, Jr., Edward McLeroy, Philip D. Jones, Gardner Spungin, Ceil Smith, Andrew Effart, Lloyd Scott, and Georgia West-Balkin. This article is the first chapter in a forthcoming book,A Handbook to College Publishing, for which the author is currently seeking a contract himself. 相似文献
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The term professional vision points to the many nuanced ways professionals see. This paper traces the development of a professional vision of a researcher and a teacher looking at classroom practices. The researcher’s interest was to capture and study notable aspects of the teacher’s practice. Through a coding scheme, disparate classroom events were organized and analyzed to yield a researcher’s professional vision of the teacher’s practices. For the teacher, through reviewing the video records of his own classroom practices, his professional vision provided a basis for him to reflect and develop professionally. Leveraging on the work of the researcher, he initiated and transformed his own practices. Their collaboration yielded a mutually informed development of professional vision of classroom practices. In juxtaposing the two developments, the researcher and the teacher’s views can be contrasted, their distinctive interests highlighted and common grounds explored. Some implications for developing professional vision are drawn, and it is in the common grounds of the teacher’s professional development and seeing with a goal of enhancing of student learning that hold some promise of a mutual interest in developing a professional vision of classroom practices. 相似文献