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11.
It has been two months since a boom of online education triggered by the epidemic in China. At present, we are keeping focus on how to optimize our online class. In the case of chemistry laboratory courses, there's not much that can be done to experimental operations through online teaching. While for the traditional teaching procedure, there is still room for improvement in terms of integrating research to teaching, interactivity, etc. This paper will present some design strategies for improving teaching the organic chemistry laboratory online. To be specific, it describes how teaching materials like the lesson plan and virtual lab were coordinated into the online teaching. And we will also discuss the holistic approach to a better outcome for students' active learning and integration research into teaching by redesigning multiple phases, such as the pre-laboratory preparation, live online class, experimental operations. 相似文献
12.
科学评价大学生科研创新能力对我国科研水平的提高具有重要意义.采用机器学习模型来预测大学生科研能力可以起到良好的效果,提出一种GAXGBoost模型来实现对大学生的科研能力预测.此模型是以Xgboost算法为基础,然后充分利用遗传算法的全局搜索能力自动搜索Xgboost最优超参数,避免了人为经验调参不准确的缺陷,最后采用精英选择策略以此确保每一轮都是最佳的进化结果.通过分析表明,所采用的GAXGBoost模型在大学生科研能力预测的结果中具有很高的精度,将此模型与Logistic Regression、Random Forest、SVM等模型进行对比,GAXGBoost模型的预测精度最高. 相似文献
13.
通过构造一个特殊的锥,利用范数形式的锥拉伸锥压缩不动点定理,在允许非线性项变号无下界且没有任何单调性假设的条件下,得出了一类高阶(k,n-k)共轭两点边值问题方程组正解的存在性结论. 相似文献
14.
Dr. Benjamin Mudrak Sara Bosshart Prof. Dr. Wolfram Koch Allison Leung Dr. Donna Minton Dr. Mitsuo Sawamoto Dr. Sarah Tegen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(2):e202215847
ChemRxiv was launched on August 15, 2017 to provide researchers in chemistry and related fields a home for the immediate sharing of their latest research. In the past five years, ChemRxiv has grown into the premier preprint server for the chemical sciences, with a global audience and a wide array of scholarly content that helps advance science more rapidly. On the service's fifth anniversary, we would like to reflect on the past five years and take a look at what is next for ChemRxiv. 相似文献
15.
Mingqi Sun Jiaqi Meng Weier Bao Dr. Ming Liu Xiaojuan Li Zicheng Wang Zhecheng Ma Prof. Dr. Xuefei Wang Prof. Dr. Zhiyuan Tian 《Chemphyschem》2023,24(6):e202200716
Room temperature phosphorescence (RTP) materials are characterized with emission after removing the excitation source. Such long-lived emission feature possesses great potential in biological fluorescence imaging because it enables a way regarding temporal dimension for separating the interference of autofluorescence and common noises typically encountered in conventional fluorescence imaging. Herein, we constructed a new type of mesoporous silica nanoparticles (MSNs)-based composite nanoparticles (NPs) with dual-color long-lived emission, namely millisecond-level green phosphorescence and sub-millisecond-level delayed red fluorescence by encapsulating a typical RTP dye and Rhodamine dye in the cavities of the MSNs with the former acting as energy donor (D) while the latter as acceptor (A). Benefiting from the close D-A proximity, energy match between the donor and the acceptor and the optimized D/A ratio in the composite NPs, efficient triplet-to-singlet Förster resonance energy transfer (TS-FRET) in the NPs occurred upon exciting the donor, which enabled dual-color long-lived emission. The preliminary results of dual-color correlation imaging of live cells based on such emission feature unequivocally verified the unique ability of such NPs for distinguishing the false positive generated by common emitters with single-color emission feature. 相似文献
16.
It is considered the class of Riemann surfaces with dimT1 = 0, where T1 is a subclass of exact harmonic forms which is one of the factors in the orthogonal decomposition of the spaceΩH of harmonic forms of the surface, namely The surfaces in the class OHD and the class of planar surfaces satisfy dimT1 = 0. A.Pfluger posed the question whether there might exist other surfaces outside those two classes. Here it is shown that in the case of finite genus g, we should look for a surface S with dimT1 = 0 among the surfaces of the form Sg\K , where Sg is a closed surface of genus g and K a compact set of positive harmonic measure with perfect components and very irregular boundary. 相似文献
17.
Shi Xianying 《大学化学》2015,30(5):26-31
将有机化学的研究前沿、热点领域及其应用引入到课堂教学中,不仅使教学内容更加丰富、生动、深入,还可以拓宽学生的知识面,激发学生学习有机化学的兴趣,提高学生学习的热情和积极性。结合多年来有机化学教学实践及接触的前沿、热点领域,列出科研成果在有机化学教学中渗透的几个具体实例。 相似文献
18.
论述了教学研究的重要性和复杂性。提出撰写教学研究论文应符合先进性、创新性、实证性、示范性和发展性等原则。介绍了教学研究涉及的主要领域,研究的主要内容和方法,对如何开展各领域教学研究并撰写高水平的教学研究论文进行了讨论并给出了示例。 相似文献
19.
Anneli Kruve Riin Rebane Karin Kipper Maarja-Liisa Oldekop Hanno Evard Koit Herodes Pekka Ravio Ivo Leito 《Analytica chimica acta》2015
This is the part I of a tutorial review intending to give an overview of the state of the art of method validation in liquid chromatography mass spectrometry (LC–MS) and discuss specific issues that arise with MS (and MS/MS) detection in LC (as opposed to the “conventional” detectors). The Part I briefly introduces the principles of operation of LC–MS (emphasizing the aspects important from the validation point of view, in particular the ionization process and ionization suppression/enhancement); reviews the main validation guideline documents and discusses in detail the following performance parameters: selectivity/specificity/identity, ruggedness/robustness, limit of detection, limit of quantification, decision limit and detection capability. With every method performance characteristic its essence and terminology are addressed, the current status of treating it is reviewed and recommendations are given, how to determine it, specifically in the case of LC–MS methods. 相似文献
20.
STREAM教育属于典型的跨学科教育形式,在学科融合的背景下,基于STREAM理念视角解决实际问题,注重在实践过程中培养和增强学生的批判思维与解决问题的能力,提升跨学科和创造性思维,使学生成为具有科学创新和革新精神的全面发展的人。融合STREAM理念开发初中化学教学案例,并将其应用于教学中,通过使用原创教学案例“水的组成”进行实践教学,研究其对教学效果及学生化学核心素养的提升作用;在实践过程中设有实验班与对照班,通过纸笔测试和问卷调查进行数据收集,结果显示不管在知识掌握度还是素养养成和促进方面,实验组都明显优于对照组,这说明融合STREAM理念对化学的教与学都具有积极作用。 相似文献