102 resultados para matematik årskurs 4-6

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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一种新型的2,4-二取代氨基-6-取代-[1,3,5]三嗪或1,3-嘧啶衍生物及其制备方法、药物组合物和其药理用途,其结构通式如式(I)所示,其中R1、R2、R3、R4、R5、R6、A、B、X、Y和Z的定义如说明书中所述。该类化合物与HIV-1整合酶具有很高结合活性,并且在底物竞争测试中能够有效的抑制整合酶对底物的结合。因此该类化合物是较强的HIV-1整合酶抑制剂,有望开发成为新的抗HIV病毒药物。

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Mg-4Al-0.4Mn-xPr (x = 1, 2, 4 and 6 wt.%) magnesium alloys were prepared successfully by the high-pressure die-casting technique. The microstructures, mechanical properties, corrosion behavior as well as strengthening mechanism were investigated. The die-cast alloys were mainly composed of small equiaxed dendrites and the matrix. The fine rigid skin region was related to the high cooling rate and the aggregation of alloying elements, such as Pr. With the Pr content increasing, the alpha-Mg grain sizes were reduced gradually and the amounts of the Al2Pr phase and All, Pr-3 phase which mainly concentrated along the grain boundaries were increased and the relative volume ratio of above two phases was changed. Considering the performance-price ratio, the Pr content added around 4 wt.% was suitable to obtain the optimal mechanical properties which can keep well until 200 degrees C as well as good corrosion resistance. The outstanding mechanical properties were mainly attributed to the rigid casting surface layer, grain refinement, grain boundary strengthening obtained by an amount of precipitates as well as solid solution strengthening.

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无水碳酸钾存在下6-氯-5,12-萘并萘醌与4-羟基偶氮苯在干燥DMF中反应的主要产物在某些反应条件下不是6[4-(苯基偶氮基)苯氧基]-5,12-萘并萘醌(1)。该未知反应产物2经核磁共振方法研究证实是6-(N,N-二甲氨基)-5,12-萘并萘醌。本文对化合物2的~1H-和~(13)C化学位移、偶合信息和结构作了详细归属,并推测其反应进程,实验结果表明,化合物2是由化合物1与溶剂DMF反应生成。

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The inhibitory effect of 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) and 2,4,6-tri(2-pyridyl)-s-triazine (TPT) molecules on the corrosion of mild steel in 1 mol/L HCl and microcosmic inhibitory mechanism were investigated by X-ray photoelectron spectroscopy and ellipsometry. XPS results showed that C Is and N Is peaks of TTC, C Is and N Is peaks of TPT and their integral areas were obtained, which suggested the layer of the inhibitors (TTC or TPT) should have effectively protected the mild steel surface from the corrosion; and the depression from the inhibitors for the corrosion of mild steel surface was studied using ellipsometry combined with potentiodynamic polarization and the phasic difference was gained, which displayed the inhibitory coverage of the inhibitors formed.

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Electrochemical measurement, quantum chemical method, and scanning electron microscopy (SEM) were performed to investigate the inhibitive effect of 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) and 2,4,6-tri(2-pyridyl)-s-triazine(TPT) on the corrosion of mild steel in 1mol.L-1 HCl at room temperature. Impedance spectroscopy measurement showed that the polarization resistance increased and that double layer capacitance decreased with the increase in the inhibitive concentration, and the results of potentiodynamic polarization showed that the inhibitors suppressed both cathodic and anodic processes of steel corrosion without change in the mechanism. Higher the orbital density distribution strength of the lowest unoccupied molecular orbital, higher is the molecule dipole, and lower energy gap between the energy of the highest occupied molecular orbital and the energy of the lowest unoccupied molecular orbital resulted in higher inhibitory efficiency. The results of SEM analysis showed that the metal was protected from aggressive corrosion by the addition of TTC and TPT.

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情绪表达规则是指一个人应当在恰当的情境中表达恰当的情绪。对情绪表达规则的认知发展是个体社会能力发展的一个重要方面,因此这一主题引起了国内外众多研究者的重视。但目前对童年早期儿童的研究中,大多数只考查了儿童对情绪的外显表达与内隐真实体验的区分,没有同时考查儿童对需要使用情绪表达规则的情境的认知,不能全面真实地揭示儿童对情绪表达规则的认知发展。在本研究中,以个别访谈法考查了4-6岁儿童同一个体在这两个指标上对情绪表达规则认知的发展,以及发展中的个别差异和个体内部差异,并进一步了解情境因素以及心理理论能力、执行抑制能力的发展对它们的影响。主要结果如下: (1)4-6岁儿童对情绪表达规则的认知能力随年龄增长而提高:4岁尚处于发展的萌芽水平,5岁和6岁都处于发展的过渡水平。对于同一年龄的儿童,对情绪表达规则的认知发展存在较大的个体之间的差异。 (2)4-6岁儿童对情绪表达规则的认知也存在较大的个体内部差异:对表情伪装的认知滞后于对需要使用情绪表达规则的情境的认知,对言语伪装的认知优于对表情伪装的认知;在对情绪表达规则的使用中,自我定向的占多数,其次是他人定向,规则定向所占的比例最少。随年龄的增长,自我定向的比例减少,他人定向的比例增多。 (3)情境变量影响4-6岁儿童对情绪表达规则的认知:与同伴交往情境中对需要使用情绪表达规则的情境的认知、对言语伪装的认知优于与长辈交往情境中的有关认知;对需要掩藏消极情绪情境中对表情伪装的认知要优于对需要掩藏积极情绪情境中表情伪装的认知。 (4)4-6岁儿童心理理论能力的发展和执行抑制能力的发展与其对情绪表达规则的认知发展有关。 (5)有关情绪表达规则的提示能够促进儿童对情绪隐私的认知,促进的效果随年龄的增长而提高,6岁的效果最好。