“程序试切法”对刀在数控车床对刀中的应用

本文在数控车床常用的"试切法"对刀的基础上,提出了"程序试切法"对刀方法。选择数控车床加工常用刀具,给出了"程序试切法"对刀的对刀步骤、试切程序和"试切法"对刀的误差修正方法,并分析了"程序试切法"对刀的优缺点。     

颠沛流离 生生不息——抗战内迁绵阳的国立第六中学校纪实

在绵阳现代教育史上,曾有一所直属教育部的中学,那就是在抗战时期,为躲避战乱,山东部分中等学校教职员和学生按照国民政府教育部的命令,颠沛流离,辗转数千里,在绵阳建立的一所直属教育部的联合中等学校——国立第六中学校,简称国立六中。     

借助世博平台 做大做强中国第一经济广播

在上海世博会这样的重大宣传报道战役中,专业广播频率如何扬独家之优势,脱离同质化竞争,成为摆在广播人面前的一个重大课题。中央电台经济之声将世博会报道融入频率改革进程之中,借助世博会报道探索改革新模式,打造中国第一经济广播品牌,以改革的实践推动世博报道形成独特优势。     

课堂内的民主:民主主义理想的一项根基--《杜威论教育与民主主义》述评

杜威(John Dewey,1859-1952)的民主主义教育思想是教育史上的一颗绚丽瑰宝.呼唤民主的教育,借以实现民主社会和民主主义理想,是杜威教育哲学的核心所在.只要民主没有过时,杜威的民主主义教育思想就保有浓郁的时代性.对杜威民主主义教育思想的解读和挖掘,是近一个世纪以来海内外众多学者孜孜以求的工作.香港中文大学及美国密西根大学教育讲座教授杜祖贻先生的专著<杜威论教育与民主主义>就这一问题做出了深入而独到的探索.     

塔里木盆地高压凝析气田开发技术研究及应用

凝析气藏开发是油气藏开发的一个重要分支,塔里木盆地凝析气田开发开创了国内油气藏的新领域。开发得到的产品是天然气、乙烷、液化气、轻烃和凝析油,在炼油和化工中具有极高的价值。塔里木盆地凝析气田累计探明储量占全国的40%,而且具有埋藏深、压力高、上覆地层复杂、流体性质复杂等特点,高效开发难度大、技术要求高。凝析气田开发技术从"七五"开始研究,经过长期的刻苦攻关,特别是"九五"以来一直被列为中石油和国家重大科技攻关项目,取得了重大突破,该项技术填补了国内高压凝析气藏开发技术的空白。 一、立项背景凝析气在原始地层条件下…     

Imbalanced free radicals and antioxidant defense systems in schizophrenia： A comparative study

Objective： To examine changes of blood oxidative-antiovidative level in schizophrenic patients and its relationship with clinical symptoms. Methods： Forty-six Chinese patients met DSM-IV （Diagnostic and Statistical Manual of Mental Disorders-iV） criteria for schizophrenia and fifty age- and sex-matched healthy controls were enrolled in the present study. Baseline psychiatric symptom severity was assessed with brief psychiatric rating scale, positive and negative syndrome scale on the blood draw day. Fresh blood samples were collected to measure levels of nitric oxide and lipid peroxide in plasma as well as activities of superoxide dismutase, catalase and glutathione peroxidase in red blood cells by spectrophotometric assays simultaneously. Results Comparison of the biochemical parameters indicated that the level of nitric oxide and lipid peroxide increased in patient group, which represented a positive correlation with positive scale scores; while the activities of three critical enzymes decreased and showed a negative linear correlation. Conclusion： This study showed that there are dysregulation of free radical metabolism and poor activities of the antioxidant defense systems in schizophrenic patients. Excess free radicals formation may play a critical role in the etiology of schizophrenia. Using antioxidants might be an effective therapeutic approach to partially alleviate or prevent the symptoms of schizophrenia.     

Functional analysis of helicase and three tandem HRDC domains of RecQ in Deinococcus radiodurans

RecQ is a highly conserved helicase necessary for maintaining genome stability in all organisms. Genome comparison showed that a homologue of RecQ in Deinococcus radiodurans designated as DR1289 is a member of RecQ family with unusual domain arrangement： a helicase domain, an RecQ C-terminal domain, and surprisingly three HRDC domain repeats, whose function, however, remains obscure currently. Using an insertion deletion, we discovered that the DRRecQ mutation causes an increase in gamma radiation, hydroxyurea and mitomycine C and UV sensitivity. Using the shuttle plasmid pRADK, we complemented various domains of the D. radiodurans RecQ （DRRecQ） to the mutant in vivo. Results suggested that both the helicase and helicase-and-RNase-D-C-terminal （HRDC） domains are essential for complementing several phenotypes. The complementation and biochemical function of DRRecQ variants with different domains truncated in vitro suggested that both the helicase and three HRDC domains are necessary for RecQ functions in D. radiodurans, while three HRDC domains have a synergistic effect on the whole function. Our finding leads to the hypothesis that the RecF recombination pathway is likely a primary path of double strand break repair in this well-known radioresistant organism.     

产业融合环境下我国图书出版产业组织合理化目标模式探讨

产业融合是在数字技术、网络技术和信息技术发展下出现的新现象,正在推动产业组织的演进,包括市场结构、市场行为和市场绩效自身的发展变化和相互关系的演进.     

内隐学习理论在图书馆的应用

内隐学习是无意识地获得刺激环境中的复杂知识的过程。文章首先介绍了内隐学习的概念和特征,接着分析了图书馆应用内隐学习理论的意义,最后提出了图书馆推行内隐学习理论的若干途径。参考文献5。     

我的笔墨缘

记得22年前,从学校分配到江西省一个边远的小县城农业局上班,工作两年多的我,还是个懵懂小伙,环境还没完全适应就被调到档案局这个全新的工作岗位。刚来时,对档案局这个陌生的环境很茫然,觉得有点不可思议,档案的概念非常模糊,以为档案就是指人事档案,保管好就行了,还以为档案部门是个非常清闲的地方。当我翻开密密麻麻写满了文字目录的档案资料时,门类繁多的档案里面包含了很多我不知道的东西,里面还有那么多学问,档案在那时就深深吸引了我。现在我在兰台这个平凡的工作岗位一待就是23个年头,看到许多和我一起工作的同事、同学纷纷调动工作或升任职务的同时,我却一直坚守在这里,并在档案事业中找到了自己人生的支点,找到了自己应该努力的方向。