抗磁性起源的两种经典解释

某些物质在外磁场作用下 ,呈现出抗磁性 ,现在的教材中对抗磁性起源主要是用电子轨道进动和电磁感应两种经典解释。论文对两种结果等效性作论证并予讨论     

运用平面斜坐标解高考题尝试

我们知道,根据平面向量基本定理,在一个平面内,给定2个不共线的向量i、j,任何一个向量→↑OP都可以用这2个向量表示成→↑OP=λ1i＋λ2j．若i⊥j,则可以i、j作为基底,建立平面直角坐标系,     

物质的抗磁性

从物质的微观结构入手,用“经典”计算法探讨物质的抗磁性。     

电磁场理论中的四维电磁势

用现代观点审视,在电磁场理论中势量→↑A、ψ是比场量→↑E、→↑B更基本的物理量。本文对势的电磁场理论予以简明清晰的论述。     

线段的定比分点新解

新教材中关于点P分有向线段→↑P1P2所成比是这样定义的：设P1P2是直线l上的两点，点P是l上不同于P1、P2的任意一点，则存在一个实数λ，使→↑P1P=λ→↑PP2，λ叫做点P分有向线段→↑P1P2所成的比。这是平面向量中关于定比分点的一种崭新的定义。对于这个定义的理解和教学，笔者认为和旧教材应有所区别。     

抗磁性分析方法探讨

抗磁性由磁介质的微观结构决定,其精确的分析必须借助于量子力学。普通物理学或电磁学教科书因受所论范围的限制,只能用经典或半经典方法进行分析。     

对一道高考填空题的探究

2007年高考江西卷（理）第15题为： 如图1,在△ABC中,点O是BC的中点,过点O的直线分别交直线AB,AC于不同的两点M,N,若→↑AB=m→↑AM,→↑AC=n→↑AN,则m＋n的值为____。     

→↑H仅与传导电流有关的条件及内涵

本文根据矢量场唯一性定理,对比分析了磁场强度矢量→↑H仅与传导电→↑Jt有关的充要条件及内涵,进而阐述了在该条件下磁化场的特点及典型应用。     

一类解几综合题解析

平面向量融进解析几何题后，为已知条件给出创设了新的情境，此类题体现了新知识与旧知识的有机结合，解决起来要求学生要有较强的分析问题、解决问题等综合解题能力，从而平面向量与解析几何题综合成为高考命题的趋势，本文探究以→↑a=λ→↑b形式给出条件的向量与解几综合题的一种解法。     

一道联考错题的分析和改进

1．问题背景 2008年12月浙江省五校第一次联考中有这样一道题：在△ABC中，满足→↑AB⊥→↑AC，M是BC的中点．     

The role of phonological and syntactic awareness in second-language reading: The case of Spanish-speaking learners of French

Spanish-speaking learners of French, aged 9 to 11 years old, were tested after approximately 7months of French instruction to explore the contribution of phonological and syntactic awareness in L2 in 4 components of L2 reading, taking oral competence in L2 andreading in L1 into account. Phonological tasksin L2 better explain decoding. Word recognitionthrough the visual route is best explained bythe corresponding ability in L1. Sentencecomprehension is best explained by oralcompetence in L2, although it is stronglycorrelated with syntactic awareness. Finally,text comprehension is explained by thecorresponding ability in L1, althoughcorrelations with syntactic awareness and oralcompetence are strong. Theoretical implicationsare derived from these findings, and questionsrelative to the subjects' age and level ofbilingualism as well as methodological issuesare discussed.     

甲申三百六十年启思--兼谈保持"两个务必"与弘扬民族精神

文章首先简引了报载《安徽阜阳旧官场群丑图》与郭沫若《甲申三百年祭》一文，介绍了毛泽东同志对郭文的高度评价与有关论断．论述了“两个务必”的提出．引用了党中央历届领导对“两个务必”的重要指示；然后，论述了“两个务必”的重大作用及其同立党为公、执政为民的关系；最后，论述了惩治腐败与干部队伍建设的有关问题。文中还阐述了关注甲申同弘扬民族精神的密切关系。     

Reading in two orthographies: A cross-linguistic study of Dutch average and poor readers who learn English as a second language

The present study investigated the reading of secondary school students in their first and second language (L1, L2). Twenty-six average and twenty-six poor readers matched on age, gender, listening and reading comprehension participated. They were native Dutch speakers who started learning English at secondary school (grade 7). We examined whether differences in L2 between the two groups reflect differences in L1 with regard to reading and relevant subskills. In addition, the relationship between reading and its predictors within and across the two languages was investigated. Between group differences were similar in L1 and L2 when task conditions involved high levels of phonological and orthographic complexity or demanded speeded processing. Furthermore, serial rapid naming predicted speeded word reading in both languages and L2 text reading accuracy, while L2 phoneme awareness and orthographic knowledge explained unique variance in L2 text reading accuracy. Cross-linguistic prediction revealed that speeded word reading predicted its counterpart from L1 to L2 and vice versa. Serial rapid naming explained additional variance in the prediction of L2 from L1. After exclusion of the reading predictor from the model, serial rapid naming was the most consistent cross-linguistic predictor, while L2 orthographic knowledge explained a small amount of unique variance in L1 speeded word reading.     

Predicting reading achievement for Kindergarten boys and girls

This study assessed the validity of the Kindergarten Teacher Rating Scale (KTRS) in predicting reading achievement for male and female students. The KTRS was a significant predictor of reading achievement for both boys and girls; differential predictive validity for boys and girls was not found. The KTRS explained about 30% of the variance in reading achievement both at the end of the 1st grade and the beginning of 2nd grade. The proportion of variance in reading achievement explained by variance in KTRS scores was significantly greater than the proportion of variance in reading achievement explained by variance in reading readiness scores. There were no significant differences in the mean KTRS scores for male and female students.     

NO_2、N_2O_4分子的空间构型和键合作用

用价层电子对互斥理论、杂化轨道理论和分子轨道理论的基本观点阐明了NO2、N2O4分子的键合作用,给出这两种分子空间构型及结构数据的解释.     

The relationship between measures of vocabulary and narrative writing quality in second- and fourth-grade students

The purpose of this study was to examine the relationship between measures of written vocabulary and writing quality. Participants included 92 second-grade students and 101 fourth-grade students. Students completed two writing samples: one an experimenter-developed writing task and the other, a standardized assessment of writing quality. Research questions examined whether four vocabulary measures (vocabulary diversity, less frequent vocabulary, mean syllable length, number of polysyllabic words) demonstrated developmental differences, whether the vocabulary measures remained stable across two different writing prompts, and whether the vocabulary measures explained unique and shared variance beyond that explained by compositional length and compositional spelling. The results indicated that vocabulary diversity and less frequent vocabulary showed developmental differences across the two writing tasks. Vocabulary diversity was the only variable to remain stable across the two writing tasks. Commonality analysis revealed that vocabulary measures explained unique and shared variance in writing quality in all four models (2 grades and 2 writing prompts). Generally, vocabulary diversity was the most stable and consistent of the four vocabulary variables.     

A Multi-level Examination of College and Its Influence on Ecumenical Worldview Development

This multi-level, longitudinal study investigated the ecumenical worldview development of 13,932 students enrolled in one of 126 institutions. Results indicated that the final hierarchical linear model, consisting of institution-and-student-level predictors as well as slopes explaining the relationships among some of these predictors, explained 39.98% of variance in Time 2 ecumenical worldview. Specifically, differences in ecumenical development trajectories for men and women could be partially explained by the average amount of religious struggle reported by students. Implications for college impact researchers and student development scholars are discussed.     

三甲基铝双聚体的结构和键合作用

以杂化理论、闭合的三中心两电子键模型对Al2 (CH3 ) 6之键角、键长等作出合理的解释 ,明确Al2 (CH3 ) 6的空间构型     

Reading with meaning: the contributions of meaning-related variables at the word and subword levels to early Chinese reading comprehension

This study examined the associations of three levels of meaning acquisition, i.e., whole word (vocabulary), morpheme (morphological awareness), and semantic radical (orthography-semantic awareness) to early Chinese reading comprehension among 164 Hong Kong Chinese primary school students, ages 7 and 8?years old, across 1?year. With time 1 word reading, phonological awareness and speeded naming controlled, morphological awareness was uniquely associated with concurrent and subsequent reading comprehension; orthography-semantic awareness uniquely explained concurrent reading comprehension at time 2. Together, the meaning acquisition variables explained between 2 and 6% unique variance in reading comprehension across time, underscoring the importance of acquisition of meaning for early reading comprehension among Chinese children.     

General auditory processing,speech perception and phonological awareness skills in Chinese–English biliteracy

This study focused on the associations of general auditory processing, speech perception, phonological awareness and word reading in Cantonese‐speaking children from Hong Kong learning to read both Chinese (first language [L1]) and English (second language [L2]). Children in Grades 2–4 (N=133) participated and were administered measures of IQ, word reading, phonological awareness, speech perception and auditory processing in both L1 and L2. Auditory processing uniquely explained both L1 and L2 word reading. While L1 speech perception accounted for unique variance in L1 word reading, L2 phonological awareness explained unique variance in L2 word reading. In cross‐language comparisons, L1 phonological awareness and speech perception were uniquely associated with L2 word reading, suggesting cross‐language transfer from L1 to L2 only. Results underscore the importance of auditory processing for reading across variable learning contexts.