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91.
介绍南京大学大理科模式化学拔尖学生培养的课程体系和教学实践的初步成果,指出该课程体系的特点是系统地传授数、理、化、生等学科的基础知识,强化化学专业核心课程,尤其注重国际化教学与交流,学生适应化学及其相关交叉学科研究。 相似文献
92.
基于教育基金保险的期权定价 总被引:1,自引:0,他引:1
本文基于文献[1]引入一种基于教育年金保险的欧式看涨期权,它赋予合约持有人在约定时间以约定价格购买一份连续支付一定年限的教育年金的权利,本文运用保险精算和期权定价的二叉树方法对其进行的定价,并说明这种合约方便于一些低收入家庭进行教育投资. 相似文献
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94.
Photodynamic therapy (PDT) has shown promise as an effective treatment modality for cancer and other localized diseases due to its noninvasive properties and spatiotemporal selectivity. Near-infrared (NIR) fluorescent dyes based on organic small molecules are characterized with low cytotoxicity, good biocompatibility and excellent phototoxicity, which are widely used in PDT. In this review, we attempt to summarize the development of imaging-induced PDT based on organic small molecules and classify it according to the structures of dyes including cyanines, 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) analogues, phthalocyanine and other agents such as rhodamine analogues. 相似文献
95.
Laura S. Rodriguez Anita Morzillo John C. Volin Todd Campbell 《School science and mathematics》2020,120(4):244-257
Our research centered on developing the Conservation Science and Technology Identity (CSTI) instruments as an empirical way to measure STEM identities and the intersection of identity constructs such as competence, performance, recognition, and ways of seeing and being. The surveys were used in a large funded multi-year project for teens and adults learning geospatial technologies and conservation science to use in intergenerational community conservation projects. We investigated whether an informal STEM learning program was developing new STEM identities or advancing well-developed identities. The instruments’ content validity was determined through a vetting process from national STEM identity research experts. Reliability was estimated with Cronbach coefficient alpha. Mann-Whitney and Wilcoxon Signed Rank tests were used to determine participants’ STEM identities and the workshop’s effect on specific identity constructs. We found teens and adults had historically similar STEM identities, with stronger conservation science than technology. Both science and technology competences, as well as technology ways of seeing and being, significantly increased, suggesting CSTI can be a valuable instrument in empirically assessing STEM identities. 相似文献
96.
This paper presents a method that creates instructionally sound learning experiences by means of learning objects. The method uses a mathematical model, distinguishes two kinds of Learning Objects Properties and proceeds in two major steps: first, the Course Creation is transformed into Set Covering under specific requirements derived from Learning Theories and practice; second, the Alternative Learning Sources are selected by using a similarity measure specially defined for this purpose. 相似文献
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98.
A general approach to the total synthesis of sesquiterpene, isolaurene (1a) and cyclolaurene (2a) is featured from commercially available 3-methyl cyclopenten-2-one. The strategy includes a Stork-Danheiser sequence concomitant with a Ni(II)-catalyzed conjugate addition of methyl group onto 3-aryl 2-methyl cyclopenten-2-one to afford the advanced intermediate 11. A methyllithium addition onto compound 11 with an eventual dehydration completed the total synthesis of isolaurene (1a) in 5 steps (58.3% overall yields). 相似文献
99.
Chenchen Wang Junfeng Zhou Yunkun Zhao Youze Chen Benli Yu Liang Lu 《Current Applied Physics》2019,19(5):646-650
This paper proposed a new method for measuring the feedback coefficient in the self-mixing interference. In experiment, the value of feedback coefficient is obtained by measuring the power difference at power jump point that based on the self-mixing vibration sensing system. It realized the measurement of feedback coefficient in range of 1–7.8 and shows a good agreement with the theoretical derivation and the corresponding simulation. Meanwhile, there is a good fitting result with the determination coefficient of 0.98 and line-width broadening factor of 3.245 respectively, which also realized measurement of feedback coefficient and line-width broadening factor at the same time. 相似文献
100.
The solid state complex between ammonium iodide and 1,4-dioxane has been found by TGA studies to be a () adduct rather than a () adduct as previously formulated. The laser Raman spectra of NH4I· dioxane and ND4I· dioxane in the N-H and N-D stretching regions show decreases in frequency compared to NH4I and ND4I which are consistent with hydrogen bonding of the N-H · O variety as a means of incorporation of the dioxane into the salt crystal lattice. 相似文献