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71.
核壳型丙烯酸聚氨酯乳液的固化与涂膜性能 总被引:1,自引:0,他引:1
制备了低交联度的核壳型丙烯酸聚氨酯乳液.采用双酚A型环氧树脂(E-44)和三羟甲基丙烷三(3-丙烯亚胺)丙酸酯(TMPTA-MAZ)作为乳液的固化剂,研究了核壳型丙烯酸聚氨酯乳液的固化与涂膜性能.研究表明:E-44和TMPTA-MAZ均可作为核壳型丙烯酸聚氨酯乳液的固化剂.两种不同类型的固化剂均能使乳液室温成膜,涂膜均一透明.TMPTA-MAZ比E-44更适合作为核壳型丙烯酸聚氨酯乳液的固化剂.当加入适量的固化剂时.涂膜的耐水、耐溶剂性以及力学性能都有很大程度的提高. 相似文献
72.
Feng-hua Chen Yi-wen Wu Huan-hong Zhang Zhan-tu Long Xiao-xin Lin Ming-zhe Chen Qing Chen Yi-fan Luo Shu-Lei Chou Rong-hua Zeng 《矿物冶金与材料学报》2021,28(10):1675-1683
p-Benzoquinone (BQ) is a promising candidate for next-generation sodium-ion batteries (SIBs) because of its high theoretical specific capacity, good reaction reversibility, and high resource availability. However, practical application of BQ faces many challenges, such as a low discharge plateau (~2.7 V) as cathode material or a high discharge plateau as anode material compared with inorganic materials for SIBs and high solubility in organic electrolytes, resulting in low power and energy densities. Here, tetrahydroxybenzoquinone tetrasodium salt (Na4C6O6) is synthesized through a simple neutralization reaction at low temperatures. The four –ONa electron-donating groups introduced on the structure of BQ greatly lower the discharge plateau by over 1.4 V from ~2.70 V to ~1.26 V, which can change BQ from cathode to anode material for SIBs. At the same time, the addition of four –ONa hydrophilic groups inhibits the dissolution of BQ in the organic electrolyte to a certain extent. As a result, Na4C6O6 as the anode displays a moderate discharge capacity and cycling performance at an average work voltage of ~1.26 V versus Na/Na+. When evaluated as a Na-ion full cell (NIFC), a Na3V2(PO4)3 || Na4C6O6 NIFC reveals a moderate discharge capacity and an average discharge plateau of ~1.4 V. This research offers a new molecular structure design strategy for reducing the discharge plateau and simultaneously restraining the dissolution of organic electrode materials. 相似文献
73.
由含固溶体二元相图提取活度 总被引:1,自引:0,他引:1
本文提出了一种由固溶体类型的二元相图提取组元活度的新公工,在该式中各组元的活度系数可以表示为组成的函数,用此公式对Ag-Pb体系进行了计算,证明了该方法是有效的的。 相似文献
74.
The defects of present methods of short-term numerical climate prediction are discussed in this paper, and four challenging
problems are put forward. Considering our under developed computer conditions, we should innovate in the approcuch of numerical
climate prediction on the basis of our own achievements and experiences in the field of short-term numerical climate prediction.
It is possibly an effective way to settle the present defects of short-term numerical climate prediction. 相似文献
75.
Giant axonal neuropathy (GAN) is a devastating sensory and motor neuropathy caused by mutations in the GAN gene, which encodes the ubiquitously expressed protein gigaxonin. Cytopathological features of GAN include axonal degeneration, with accumulation and aggregation of cytoskeletal components. Little is currently known about the molecular mechanisms underlying this recessive disorder. Here we show that gigaxonin controls protein degradation, and is essential for neuronal function and survival. We present evidence that gigaxonin binds to the ubiquitin-activating enzyme E1 through its amino-terminal BTB domain, while the carboxy-terminal kelch repeat domain interacts directly with the light chain (LC) of microtubule-associated protein 1B (MAP1B). Overexpression of gigaxonin leads to enhanced degradation of MAP1B-LC, which can be antagonized by proteasome inhibitors. Ablation of gigaxonin causes a substantial accumulation of MAP1B-LC in GAN-null neurons. Moreover, we show that overexpression of MAP1B in wild-type cortical neurons leads to cell death characteristic of GAN-null neurons, whereas reducing MAP1B levels significantly improves the survival rate of null neurons. Our results identify gigaxonin as a ubiquitin scaffolding protein that controls MAP1B-LC degradation, and provide insight into the molecular mechanisms underlying human neurodegenerative disorders. 相似文献
76.
本文报导了双—N(2—羟基乙基)β—雷锁醛亚胺合镍(Ⅱ)和双—N(2—羟基乙基)β—雷锁醛亚胺合铜(Ⅱ)的合成,它们的组成已由元素分析和红外光谱所证实。抗癌活性试验表明,双—N(2—羟基乙基)β—雷锁醛亚胺合镍(Ⅱ)对肿瘤模型S_(180)(A)及艾氏腹水癌均有较好的抑制作用. 相似文献
77.
本文采用回归设计和电算机离线调优运算,对我国某大型铜矿含多种重金属离子废水的处理进行了研究。提出了“阶段中和沉淀—浮选分离”的处理废水新工艺。建立了氢氧化铜和石膏浮选分离的数学模型,并进行了计算机绘图。最终获得了符合国家排放标准的处理水,并逐一回收了有价金属化合物氢氧化铁、氢氧化铜和石膏产品。 相似文献
78.
俞万禧 《黑龙江科技学院学报》2001,11(4):48-51
一种8t幻方及正交拉丁方的构造方法被首次发现。文中验证了4t阶幻方及正交拉丁方构造方法的可行性。阐明了8t阶幻方及正交拉丁方构造的思路。介绍了16阶幻方及正交拉丁方的构造过程,构造验证表明,该法是简便的,可构造任意8t阶幻方及正交拉丁方。 相似文献
79.
Based on the qualitative theory of atmospheric dynamical equations, a new method for simplifying equations, the operator constraint principle, is presented. The general rule of the method and its mathematical strictness are discussed. Moreover, the way that how to use the method to simplify equations rationally and how to get the simplified equations with harmonious and consistent dynamics is given. 相似文献
80.