共查询到20条相似文献,搜索用时 46 毫秒
1.
《材料科学技术学报》1999,(5)
1-IntroductionPGisanimportantindustrialby-productderivedfromphosphoricacidandphosphatefertilizerman-ufacturesbydihydrateprocess.Theamountofthiswasteexceedsconsiderablythanthemassoftheprod-uct,becausetheamountofthewastePGbeingpro-ducedintheacidrangesfrom4.5to5.5tpertonofPzOsintermsofdrymatter.ThePGissepa-ratedfromthemediumofdissolvedphosphateoreinsulphuricacidbyfiltration.WhereasthemajorpartofthepureP2O5isobtainedfromthesedimentbymeansofacountercurrentwashingwithwater[1'2l.Theobtainedfilter… 相似文献
2.
3.
在市场的需求拉动下,中国的钢铁生产5亿多吨可能都不够,但是发展太快太多,带来的后遗症太多。那么什么是钢铁工业的科学发展观?科学发展和可持续发展最关键的问题是什么? 相似文献
4.
5.
Jillian Lerner 《History of Photography》2017,41(2):108-125
As Nadar shifted his attention from caricature to photography in the 1850s, he produced several fascinating hybrid images. Among these are experiments in photomontage and uncommon portraits that combine graphic, photographic, and autographic elements. The author shows how Nadar cultivated a number of recognisable signatures, which he reiterated and adapted for different image-types, products, and advertisements. Nadar’s investment in self-portraiture, his penchant for publicity, and his ability to work across platforms and to balance artistic ambition and commercial enterprise are explored in depth. 相似文献
6.
7.
A new type of sol-gel-derived, inert metal-modified, composite, amperometric biosensor is developed. The electrodes are comprised of a dispersion of biochemically and chemically modified graphite powder in a porous, organically modified silicate (Ormosil) network. The percolating carbon dispersion provides electrical conductivity, oxidoreductase enzymes (e.g., glucose oxidase, lactate oxidase, or l-amino acid oxidase) are used for biocatalysis, metallic palladium is used for electrocatalysis of the biochemical reaction product, and the porous organically modified silica provides a rigid skeleton. The hydrophobicity of this composite material guarantees that only a limited section of the electrode is wetted by the aqueous analyte, thus providing a controlled-thickness reactive layer. The thickness of the reaction layer can be tuned by the addition of hydrophilic components. The electrode can be reproducibly renewed by removing its upper layer and exposing a new, thin, porous bioreactive section. The same technology is applicable for the production of thick-film, low-leaching, disposable sensors. In this configuration, the analysis is conducted using a single drop of the analyte applied on the hydrophobic film. The sensors are found to be stable over long periods. 相似文献
8.
9.
Engineering education research has experienced a notable scale‐up in recent years through the development of departments and degree programs, high‐profile publication outlets, research agendas, and meetings. We begin by reviewing these developments, contextualizing them historically, and clarifying some relevant terminology. We then use observational data collected at the 2007 inaugural International Conference on Research in Engineering Education (ICREE) to examine how engineering education is variously conceptualized as a discipline, community of practice, and/or field. We also examine how ICREE participants engaged with questions about the infrastructure and major goals of engineering education research. Our data reveals both an overall lack of clarity and continued sense of ambiguity about the identity and status of engineering education research. We conclude by recommending that participants and stakeholders work to clarify the goals and objectives of engineering education research, especially to inform the continued development of the field's identity and supporting infrastructures. 相似文献
10.
正王利兵,男,1967年出生,江苏南通人,博士,研究员。湖南省出入境检验检疫局党组成员、副局长。天津大学、中南大学、江南大学等国内多所著名大学兼职教授和博士生导师,国家质检总局首席研究员,国际标准化组织ISO/TC264主席,国家质检总局科学技术委员会委员,进出口商品检验专业技术委员会主任,中国标准化专家委员会委员,"十二五"国家863计划主题专家,国家国家高层次人才特殊支持计划(万人计划)专家,科技部科技创新领军人 相似文献
11.
时间悄然地跨进了2009年。在新的阳光四季里,我们即将进行新一轮的春种,夏耕,秋收,冬藏。回想中国纸包装行业发展的历程,有的企业越做越强,而有的却已消失并逐渐被人淡忘,再也没人去提起他们曾经的贡献和神勇。 相似文献
12.
Paul Konitzer was one of the outstanding and well-known physicians in the years after the World War II in East-Germany. THe paper describes his professional way as hygienist, social medical, municipal physician and last but not least as health politician in the times of four different political regimes: the imperial era in Germany till 1918, the time of "Weimarer Republic" till 1933, the Nazi dictatorship till 1945 and the early years in the Soviet occupation zone of Germany. The life of Konitzer is a typical example of the fate of a German doctor in the first half of the 20th century. Konitzer was arrested in February 1947 by the Soviet Military Government in Berlin in connection with some political troubles and reproach with a typhus epidemic in a German camp for Russian Prisoners of War in the Nazi era. On April 22nd 1947 he died in prison of Dresden by suicide without condemnation. 相似文献
13.
Hollow structures have demonstrated great potential in drug delivery owing to their privileged structure,such as high surface-to-volume ratio,low density,large cavities,and hierarchical pores.In this review,we provide a comprehensive overview of hollow structured materials applied in targeting recognition,smart response,and drug release,and we have addressed the possible chemical factors and reactions in these three processes.The advantages of hollow nanostructures are summarized as follows:hollow cavity contributes to large loading capacity;a tailored structure helps controllable drug release;variable compounds adapt to flexible application;surface modification facilitates smart responsive release.Especially,because the multiple physical barriers and chemical interactions can be induced by multishells,hollow multishelled structure is considered as a promising material with unique loading and releasing properties.Finally,we conclude this review with some perspectives on the future research and development of the hollow structures as drug carriers. 相似文献
14.
【颁奖词】关键时刻,挺身而出,是警察职责的召唤。拯救生命,义无反顾,是青春成长的典范。最美学警李博亚——失去的是双腿,留下的是90后阳光之子大爱的足迹。 相似文献
15.
<正>2009年,我国瓦楞工业包装领域为全球同业、同行提供了亠个容量最大的平台。2010年,瓦楞工业又站在了新的起点上,在追求创新的时代,让我们每一步都倾注创业的冲动,每个包装人都满怀创新的激情,朝着国际化的目标,迅跑!迅跑! 相似文献
16.
17.
如果要吸引身边的朋友一起玩宝丽来,那最好的方式就是对着他"咔嚓"一张。路摇正是这样被引诱进宝丽来的梦幻世界。采访路摇,是通过编辑部玩宝丽来的同事推荐。上海人,在宝丽来圈子很有名。如果追溯到宝丽来在国内的兴起,称路摇为 相似文献
18.
2009年,我国瓦楞工业包装领域为全球同业、同行提供了亠个容量最大的平台。2010年,瓦楞工业又站在了新的起点上,在追求创新的时代,让我们每一步都倾注创业的冲动,每个包装人都满怀创新的激情,朝着国际化的目标,迅跑!迅跑! 相似文献