GeoGebra软件与高中数学教学融合——构建可视化高效课堂

信息化时代之下,信息技术被广泛运用于教育当中,在教师的素养教育上发挥出很好的推动效力.特别是在数学教学当中,对GeoGebra软件的良好应用,可以大幅增强课堂教学水平,提升教学成效.GeoGebra软件有助于教师更有效地完成数学的可视化课堂教学,创新了数学课程的教学模式,有着十分重要创新价值与融和意义.本文与实际教学案例相结合,探讨了应怎样借助GeoGebra软件和高中数学的教学融合,建立可视化高效课堂,增强学生在数学方面的核心素养.     

漆酚镨高聚物吸附有害气体的性能研究

由漆酚和PrCl3在热溶液中合成的漆酚镨高聚物(PUPr),中心原子Pr(Ⅲ)的配位数并未达到饱和,具有进一步接受电子的能力.本文研究了Pr(Ⅲ)接受带孤对电子的有害气体SO2、HCHO、H2S和NH3作为配体的能力及其选择性.结果表明,PUPr对于电负性较大的硬碱配位体SO2的吸附性能较佳,且吸附速率较快,1h吸附量就达到4.05mmol/g.     

新喜树碱衍生物的核磁共振谱分析与结构鉴定

以20(S)-喜树碱(CPT)为起始原料,对其进行结构修饰,合成了一种新的喜树碱衍生物CPT-A.并利用1D(~1H、~(13)C和DEPT135)和2D(异核单量子相关谱和异核多碳相关谱)核磁共振(NMR)技术对该化合物进行了结构确定,详细归属了CPT-A~1H和~(13)C NMR谱的化学位移,喜树碱骨架的指认结果与文献报道基本一致,并发现喜树碱骨架6位碳与取代基苯环3’位碳的化学位移相同,谱峰完全重叠,这在~(13)C谱中是不常见的.研究结果可为喜树碱类天然产物的发现和结构鉴定提供NMR数据支持和方法指引.     

Na2CaSiO4∶RE3+(RE=Ce3+,Tb3+,Eu3+) 的制备及发光特性

采用高温固相法,合成了三价稀土离子(RE³⁺=Ce³⁺, Tb³⁺, Eu³⁺)掺杂的Na₂CaSiO₄(NCS)系列样品,并研究了其在紫外光激发下的发光特性。研究结果表明,Ce³⁺、Tb³⁺ 和Eu³⁺掺杂的NSC系列样品在紫外光源激发下,均呈现其特征发射,随着掺杂浓度的提高,发射强度逐渐增大。Ce³⁺、Tb³⁺和Eu³⁺的最佳摩尔分数分别为0.13、0.13和0.12,相应的色坐标分别计算为(0.17, 0.17)、(0.34, 0.58)和(0.66, 0.34),分别为很好的蓝光、绿光和红光。继续增加稀土离子的含量,发射强度降低。     

On a Problem of Approximation by Linear Means

is valid, where ω(f,δ) is the modulus of continuity of f. Furthermore they asked that: (1.3) If Theorem A can be extended to matrix summability? Later, P. D. Kathal, A. S. B. Holland and B. N. Sahney partially answered this problem. They proved the following Theorem B If {Λ_(n,k)} is monotonic non-increasing for all 0≤k≤n and Λ_(n,k)≥0 (0≤k≤n),Λ_(n,k)=0 (k>n), then we have     

CHARACTERIZATION AND PROPERTIES OF URUSHIOL POLYMER CONTAINING BORON-NITROGEN COORDINATE BOND

Urushiol polymer containing B--N bond (PUBN) was synthesized with urushiol-boronpolymer and diethylene triamine. Its structure was characterized by XPS, IR, UV, HPLC,DTA-TG and elemental analysis. The physico-mechanical and anticorrosive propertiesof the polymer were also investigated. The results show that the coating of PUBN canbe hardened in 2h at room temperaure and its film has excellent physico-mechanicalproperties and good anticorrosive properties.     

CYTOCHEMICAL STUDY OF ELECTRON MICROSCOPY ON FRUCTOSE 1,6-DIPHOSPHATASE AND URIDINE DIPHOSPHOGLUCOSE PYROPHOS PHORYLASE IN THE MESO PHYLL CELLS OF Stevia rebaudiana BERTONI

The subcellular localizations of fructose 1,6-diphosphatase (FDPase, EC 3.1.3.11) and uridine diphos-phoglucose pyrophosphorylase (UDPG PPlase, UTP:α-D-glucose-I-phosphate uridylytransferase, EC 2.7.7.9) in the mesophyll cells of a new sweetener plant (Stevia rebaudiana Bertoni), both of which arecritical in carbohydrate metabolism, were determined and the activities of both enzymes in the leaves ofdifferent ages were compared in this study. This experiment reveals: FDPase is a membrane-bound enzymeand is specifically localized on the thylakoid membranes of chloroplasts and the plasmic membranes.FDPase is only found on the thylakoid membranes of chloroplasts in the young mesophyll cells, while it isfound on both the thylakoid membranes of chloroplasts and the plasmic membranes in the mature meso-phyll cells. UDPG PPlase is distributed in the cytoplasmic matrix freely, and is localized on Golgi flat-tened sacs and Colgi vesicles in a membrane-bound form. In this study, it is suggested that the chloropla     

函数单调性在解题中的一些应用

函数的单调性在中学数学中有广泛的应用,它的应用范围远远超过高中课本所涉及的深度、广度与难度,利用它可以解办程、解不等式、求最大(小)值、求取值范围、证明等式与不等式等问题,其中某些问题的解法之巧妙、简捷、明快、无不使人耳目一新,举例如下:     

氟钽酸钾中氟的除去和微量碳的测定

本提出铝片－硼酸－磷酸十硼酸饱和液的新除氟体系。系统地研究了铝片的用量，燃烧温度，燃烧时间和氧气流速对除氟和二氧化碳析出的影响。用燃烧－气相色谱法测定了氟钽酸钾中微量，方法的检测限为５μｇ／ｇ，相对偏差为±１０％，已应用于有关工厂的日常分析。     

N,N'''',N″-三香草醛缩三氨乙基胺及其稀土硝酸盐配合物的合成、表征与抗肿瘤活性

合成了三脚架型席夫碱配体N,N',N"-三香草醛缩三氨乙基胺(C30H33N4O3(OH)3,L)及其稀土硝酸盐配合物.通过元素分析、红外光谱、核磁共振及热分析谱对它们进行了表征.同时,初步研究了配体及其部分稀土配合物对人体白血病细胞的抑制作用.