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111.
论矿物材料计算与设计 总被引:5,自引:0,他引:5
矿产资源产业是国民经济的基础产业,非金属矿产是重要的固体矿产之一,80%的矿物用于材料工业,矿物加工是矿产资源高效利用、制备矿物材料的重要加工技术环节,矿物材料是国民经济中高新技术材料的重要组成,材料科学及矿物材料学科的发展,为矿物材料计算与设计理论的提出奠定了实际基础.借鉴材料设计与计算的理论和方法,在总结、分析和研究矿物加工及矿物材料制备方面大量的理论研究和实际成果的基础上,提出了矿物材料计算与设计及功能性矿物材料、复合材料化学改性药剂分子设计与模拟的学术思想,论述了矿物材料计算与设计的基本科学技术问题、研究内容、相关学科体系、研究层次及其学科地位.其意义在于:使矿物加工工程学科发展和功能性矿物材料的研发,建立在基本科学原理基础之上,将矿物加工工程学科的主要研究内容统一在总体的方向、目标之内,横向拓展了相关学科理论的研究范围;根据矿物结构、组成,通过设计与计算,对矿物材料性能进行预测、预报,进而为制备提供最佳技术路线;对于已知性能的矿物材料优化制备路线,系统分析各种矿物的结构与组成及其所具备固有性质,针对各种材料性质要求,排列对应关系,为复合材料的制备奠定基础,进而实现矿物资源的高效开发和利用,同时,使得材料设计或计算材料的学科基础向研究矿物组成与结构的纵向延伸,丰富了材料科学思想. 相似文献
112.
企业集群与供应链的共生性研究 总被引:13,自引:0,他引:13
针对具有时代经济特点的产业企业集群和为适应并驾驭这种经济的供应链模式,讨论了二者在具体运作过程中相互依存共同发展的共生性和战略目标上的趋同性,试图阐明二者协调发展的共生机理。 相似文献
113.
A straightforward way to prevent students from leaving education without a higher secondary diploma is increasing the compulsory education age. The idea is that, by staying longer in school, more students eventually obtain a higher secondary diploma. This paper examines the impact of a one-year increase in compulsory school-age on dropping out of secondary education by a difference-in-differences analysis. For this, we exploit a recent compulsory education policy reform in the Netherlands. After controlling for confounding factors and observable covariates, we find that the one year increase in compulsory school-age reduces dropout by 2.5 percentage points. The effect, however, is entirely situated in the group non-liable to the policy reform. We observe that native Dutch vocational students, mostly without retention in grade, but also without a higher secondary diploma at hand, more often left school in the immediate period before the policy reform. Given the economic revival at that time, this may reflect anticipation of labor market opportunities. 相似文献
114.
Veronica Macchi Andrea Porzionato Carla Stecco Cesare Tiengo Anna Parenti Adriano Cestrone Raffaele De Caro 《Anatomical sciences education》2011,4(3)
Medical Gross Anatomy lecture at the University of Padova, Italy. Gross Anatomy at the University of Padova is taught utilizing both traditional and technological resources, which are integrated with practical laboratory exercises (mainly on plastic models and plastinated specimens) as well as radiological anatomy. In this issue of ASE, Dr. Veronica Macchi and her colleagues from the Department of Human Anatomy and Physiology at the University of Padova discuss an innovative pilot project with their University Hospital in which they obtain body parts removed from patients during surgical procedures and utilize them for gross anatomy education. The cover photograph shows one of the co‐authors of this paper, Professor Raffaele De Caro and his students, performing dissection of the distal forearm and hand in the anatomy lecture theater at the University of Padova. 相似文献
115.
美国媒体金融危机预警报道等方面的缺失和公信力的大幅下降,反映了新自由主义经济政策影响下美国媒体日趋垄断化,导致新闻日益商业化和娱乐化,发生了根本性的质变。 相似文献
116.
Ford P De Ste Croix M Lloyd R Meyers R Moosavi M Oliver J Till K Williams C 《Journal of sports sciences》2011,29(4):389-402
Within the UK, the "Long Term Athlete Development" (LTAD) model has been proposed by a variety of national governing bodies to offer a first step to considering the approach to talent development. The model, which is primarily a physiological perspective, presents an advancement of understanding of developing athletic potential alongside biological growth. It focuses on training to optimize performance longitudinally, and considers sensitive developmental periods known as "windows of opportunity". However, it appears that there are a number of problems with this theoretical model that are not necessarily transparent to coaches. Principally, the model is only one-dimensional, there is a lack of empirical evidence upon which the model is based, and interpretations of the model are restricted because the data on which it is based rely on questionable assumptions and erroneous methodologies. Fundamentally, this is a generic model rather than an individualized plan for athletes. It is crucial that the LTAD model is seen as a "work in progress" and the challenge, particularly for paediatric exercise scientists, is to question, test, and revise the model. It is unlikely that this can be accomplished using classical experimental research methodology but this should not deter practitioners from acquiring valid and reliable evidence. 相似文献
117.
Evidence suggests the development of fundamental movement skill (FMS) is a key factor in promoting long-term physical activity. Low levels of activity among preschool children and the relationship between physical activity and the development of fundamental movement skills underline the need to determine the factors associated with children's development of such skills. As parents play an important role in the socialization process, the aim of this study was to examine correlates of family and neighbourhood characteristics as well as parental behaviour and beliefs on FMS performance in 4- to 6-year-old preschool children. Relationships between preschool children's FMS performance and family contextual variables were examined within a sample of 846 preschool children. Results identified positive associations of FMS performance with parental education, father's physical activity, transport to school by bicycle, and the high value placed by parents high on sport-specific aspects of children's physical activity. Variables negatively associated with preschool children's FMS performance included father-child interaction in TV-viewing and reading books, the high importance placed by parents on winning and performance in children's physical activity. Furthermore, the ambiguity of associations between FMS performance and parental beliefs underlined its complexity. 相似文献
118.
De Loof Haydée Boeve-de Pauw Jelle Van Petegem Peter 《International Journal of Science and Mathematics Education》2022,20(7):1291-1313
International Journal of Science and Mathematics Education - The “leaky pipeline” with regard to students’ engagement in Science, Technology, Engineering, and Mathematics (STEM)... 相似文献
119.
120多年来,世界范围内敦煌研究取得了一定的成就,为今后的研究奠定了基础。在这个基础上,需要认识敦煌历史文化作为精神财富对人类社会进步发展的价值意义;需要转变传统观念,改进研究方法,开创新的研究局面,促进敦煌事业的发展,为新时代坚持中国特色社会主义建设提供精神支撑。 相似文献
120.
Nele S. Pauwels Ann De Meulemeester Alessia Romagnoli Heidi Buysse Renaat Peleman 《Health information and libraries journal》2021,38(1):66-71
This is part of a new series in this regular feature regarding trends in the provision of information by health science libraries. By sharing expertise and drawing together relevant trends the series intends to serve as a road map for both health science librarians and health informatics professionals. This article shows how a medical and biomedical research library changed practices, and reassessed user needs for the COVID‐19 emergency. Discusses changes to online education (and collaborative working) to provide user‐friendly services, researcher support tailored to need and re‐visioning library space. J.M. 相似文献