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1.
数学底层思维即用数学的眼光观察世界、用数学的思维分析世界以及用数学的语言表达世界,是人们面对自然和社会中纷繁多样的现象和问题时,所展现的自发的、不依赖监督的、融汇数学学科核心素养的思维方式.作为国家高中新课程标准中数学六大核心素养之一的数学建模,是培养学生数学底层思维的良好载体,对人才培养和社会发展均起到良好的促进作用.本文主要阐述了数学建模对高中生构建数学底层思维的作用,并结合教学实例给出教学实施建议. 相似文献
2.
Shuangshuang Long Weijie Chi Lu Miao Qinglong Qiao Xiaogang Liu Zhaochao Xu 《中国化学快报》2019,30(3):601-604
Both experimental and computational studies showed owing to strong π-π stacking interactions, 1-acetylpyrene mainly exists in dimers and molecular aggregates even at low concentrations, which led to the mis-assignment of its monomer emission peaks. 相似文献
3.
Shang‐Xiong Huang‐Fu Jin‐Ni Shen Prof. Hua Lin Prof. Ling Chen Prof. Li‐Ming Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(27):9809-9815
A novel type of supertetrahedral connectivity is exhibited by the 72‐atom discrete supercubooctahedron in (Cs6Cl)2Cs5[Ga15Ge9Se48] ( 1 ), which undergoes both cation and anion exchange, as revealed by unambiguous single‐crystal X‐ray diffraction data. Electronic‐structure studies helped to understand the Ge/Ga distribution. 相似文献
4.
Wen‐Jing Guo Yong‐Tao Wang De‐Xian Kong Jin‐Yun Wang Prof. Qiao‐Hua Wei Guo‐Nan Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(11):4205-4208
A heterometallic cluster [Ag6Au6(ethisterone)12] of an unprecedented topology was synthesized and characterized. A sensitive and specific probe for estrogen receptor α (ERα) has been developed for the first time based on the enhancement of the Ag6Au6 luminescence. 相似文献
5.
6.
Yi Liu Jiaqi Wang Shiguo Han Dr. Xitao Liu Maofan Li Zhiyun Xu Wuqian Guo Prof. Maochun Hong Prof. Junhua Luo Prof. Zhihua Sun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(16):3494-3498
3D perovskite CsPbBr3 has recently taken a blooming position for optoelectronic applications. However, due to the lack of natural anisotropy of optical attributes, it is a great challenge to fulfil polarization-sensitive photodetection. Here, for the first time, we exploited dimensionality reduction of CsPbBr3 to tailor a 2D-multilayered hybrid perovskite, (TRA)2CsPb2Br7 ( 1 , in which TRA is (carboxy)cyclohexylmethylammonium), serving as a potential polarized-light detecting candidate. Its unique quantum-confined 2D structure results in intrinsic anisotropy of electrical conductivity, optical absorbance, and polarization-dependent responses. Particularly, it exhibits remarkable dichroism with the photocurrent ratio (Ipc/Ipa) of ≈2.1, being much higher than that of the isotropic CsPbBr3 crystal and reported CH3NH3PbI3 nanowire (≈1.3), which reveals its great potentials for polarization-sensitive photodetection. Further, crystal-based detectors of 1 show fascinating responses to the polarized light, including high detectivity (>1010 Jones), fast responding time (≈300 μs), and sizeable on/off current ratios (>104). To our best knowledge, this is the first study on 2D Cs-based hybrid perovskite exhibiting strong polarization-sensitivity. The work highlights an effective pathway to explore new polarization sensitive candidates for hybrid perovskites and promotes their future electronic applications. 相似文献
7.
Growth of Hydrophilic CuS Nanowires via DNA‐Mediated Self‐Assembly Process and Their Use in Fabricating Smart Hybrid Films for Adjustable Chemical Release 下载免费PDF全文
Li Zhou Wei Li Zhaowei Chen Enguo Ju Prof. Dr. Jinsong Ren Prof. Dr. Xiaogang Qu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(7):2930-2935
Facile growth of CuS nanowires through self‐assembly and their application as building blocks for near‐infrared light‐responsive functional films have been demonstrated. It is found that DNA is a key factor in preparing the CuS material with defined nanostructure. An exclusive oriented self‐aggregate growth mechanism is proposed for the growth of the nanowires, which might have important implications for preparing advanced, sophisticated nanostructures based on DNA nanotechnology. By employing the hydrophilic CuS nanowire as an optical absorber and thermosensitive nanogel as guest reservoir inside alginate film, a new platform for the release of functional molecules has been set up. In vitro studies have shown that the hybrid film possesses excellent biocompatibility and the release rate of chemical molecules from the film could be controlled with high spatial and temporal precision. Our novel approach and the resulting outstanding combination of properties may advance both the fields of DNA nanotechnology and light‐responsive devices. 相似文献
8.
A new complex K0.5[K(18-crown-6)]1.5Ge9·1.5en(1) which contains unprecedented "up" and "down" chain arrangement of unit [-(Ge-9-K-Ge9)3-] has been prepared by the reaction of K4Ge9 with HgS in ethylenediamine(en) in the presence of 18-crown-6(1,4,7,10,13,16-hexaoxacyclooctadecane), and characterized by X-ray structure analysis. The color of the title crystals(black), which is darker than that of the reported three compounds with chains of germanium clusters, may result from the naked K+ and their interactions with the chain. And the structure differences between 1 and the reported three compounds with chains of germanium have also been discussed. 相似文献
9.
Inside Back Cover: Deciphering a Nanocarbon‐Based Artificial Peroxidase: Chemical Identification of the Catalytically Active and Substrate‐Binding Sites on Graphene Quantum Dots (Angew. Chem. Int. Ed. 24/2015) 下载免费PDF全文
10.
The growth, XRD patterns, spectral properties, and fluorescence decays of Yb:Ca0.28Ba0.72Nb2O6 (Yb:CBN) with doping concentration of 1 at.% and 5 at.% were studied. The peak absorption cross-section and the emission cross-section were calculated. Larger Stark splitting of Yb:CBN offers the prospect of the quasi-four level laser operation. 相似文献