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41.
丙烯酸偕二硝基丙酯(DNPA)与苯乙烯(St)在乙酸乙酯溶液中自由基共聚反应得到DNPA-St共聚物,利用红外光谱法测定了共聚物的组成,从而测得了丙烯酸偕二硝基丙酯与苯乙烯的竞聚率,采用FT-IR、1H NMR、DSC等方法研究了DNPA-St共聚物的结构和热性能.研究结果表明,用Fineman-Ross方法,求得丙烯...  相似文献   
42.
Although the piezo-catalysis is promising for the environmental remediation and biomedicine, the piezo-catalytic properties of various piezoelectric materials are limited by low carrier concentrations and mobility, and rapid electron-hole pair recombination, and reported regulating strategies are quite complex and difficult. Herein, a new and simple strategy, integrating phase boundary engineering and defect engineering, to boost the piezo-catalytic activity of potassium sodium niobate ((K, Na)NbO3, KNN) based materials is innovatively proposed. Tur strategy is validated by exampling 0.96(K0.48Na0.52)Nb0.955Sb0.045O3-0.04(BixNa4-3x)0.5ZrO3-0.3%Fe2O3 material having phase boundary engineering and conducted the defect engineering via the high-energy sand-grinding. A high reaction rate constant k of 92.49 × 10−3 min−1 in the sand-grinding sample is obtained, which is 2.40 times than that of non-sand-grinding one and superior to those of other representative lead-free perovskite piezoelectric materials. Meanwhile, the sand-grinding sample has remarkable bactericidal properties against Escherichia coli and Staphylococcus aureus. Superior piezo-catalytic activities originate from the enhanced electron-hole pair separation and the increased carrier concentration. This study provides a novel method for improving the piezo-catalytic activities of lead-free piezoelectric materials and holds great promise for harnessing natural energy and disease treatment.  相似文献   
43.
综述了磺化类表面活性剂的发展现状,介绍了正在运行的、停产及在建的磺化装置,总结了不同磺化类表面活性剂近年来的产销量及主要的生产厂家,并展望了我国磺化产业的发展趋势。  相似文献   
44.
6,13-bis(triisopropylsilylethynyl) pentacene (TIPS pentacene) from simple drop casting typically forms crystals with random orientation and poor areal coverage, which leads to device-to-device performance variation of organic thin film transistors (OTFTs). Previously, a temperature gradient technique was developed to address these problems. However, this approach simultaneously introduced thermal cracks due to the thermally induced stress during crystallization. These thermal cracks accounted for a reduction of charge transport, thereby impacting the device performance of TIPS pentacene based OTFTs. In this work, an insulating polymer, poly(α-methyl styrene) (PαMS) was blended with TIPS pentacene to relieve the thermal stress and effectively prevent the generation of thermal cracks. The results demonstrate that the incorporation of PαMS polymer combined with the temperature gradient technique improves both the hole mobility and performance consistency of TIPS pentacene based OTFTs.  相似文献   
45.
Sodium‐ion batteries (SIBs) are regarded as a complementary technology to lithium‐ion batteries (LIBs) in the effort of searching for alternative energy solutions that are cost‐effective and sustainable. The identification of suitable alternative anode materials is essential to close the gap in energy density between SIBs and LIBs. Solid‐state alloying reactions that work beyond intercalation mechanism are able to provide a significant improvement in specific capacity. This review describes key advances in SIBs with a primary emphasis on alloy anodes. Recent information and results published in the literatures are stressed to provide an overview of their development in SIBs. With the discussion of some of the remaining challenges and possible solutions, the authors hope to sketch out the scope for future studies in this field.  相似文献   
46.
Low sodium chicken broth with NaCl added to provide Na+ concentrations in typical reduced Na+ soups (144 and 288 mg Na+/240 mL serving) was thickened with commonly used gum, starch, or flour food additives. Xanthan gum suppressed saltiness as the result of ionic binding of Na+, as determined by sensory evaluation and 23Na NMR spectroscopy. Saltiness was affected by added NaCl (p = 0.0001), thickener (p < 0.01), and added NaCl* thickener (p < 0.01), and positively correlated with chicken and overall flavors (p = 0.0001). Cornstarch provided body, no suppression of salt taste, and the greatest salt enhancement of chicken and overall flavors. In complex food systems, temperature and other factors affected Na+ binding as measured by NMR pointing to the need for a new model.  相似文献   
47.
详细分析了硫酸铜浓度对过硫酸钠体系微蚀速率的影响,并对其机理进行了探讨。  相似文献   
48.
翟华敏  Lai  YZ 《中国造纸》1996,15(3):6-10
用硫化钠水溶液预处理桉树,接着进行改进的深度脱木素硫酸盐蒸煮。结果表明,在160℃预处理后脱木素的选择性较常规硫酸盐蒸煮有显著提高,可得到低Kappa值(约为10)的浆而没有明显的强度损失。  相似文献   
49.
高晗  陈帅  马振国  夏琳 《橡胶工业》2018,65(12):1379-1382
本文主要研究采用研磨的方法改性CBp,并将其应用到丁苯橡胶中,对比考察了不同研磨时间的CBp、未改性CBp、N774的粒径分布差异及在丁苯橡胶中的性能差异。研究结果表明:研磨的方法可有效减小CBp的粒径,有助于其在橡胶中更好的分散,且研磨时间越长,炭黑粒子粒径越小,门尼粘度越大,扭矩差越大。研磨后的CBp补强的丁苯橡胶的拉伸强度、撕裂强度、300%定伸强度、硬度得到有效提高,综合改性效果良好。  相似文献   
50.
With the increasing demand for low cost, long lifetime, high energy density storage systems, an extensive amount of effort has recently been focused on the development of sodium‐ion batteries (SIBs), and a variety of cathode materials have been discovered. However, looking for the most suitable anode material for practical application is a major challenge for SIBs. Herein, a high capacity sulfur‐doped black phosphorus‐TiO2 (TiO2‐BP‐S) anode material for SIBs is first synthesized by a feasible and large‐scale high‐energy ball‐milling approach, and its stability in air exposure is investigated through X‐ray photoelectron spectroscopy. The morphology of TiO2‐BP‐S is characterized using transmission electron microscopy, indicating that the TiO2 nanoparticles produce P? Ti bonds with BP. The TiO2‐BP‐S composite with P? S and P? Ti bonds exhibits excellent stability in air and the superior electrochemical performance. For example, the discharge specific capacity is up to 490 mA h g?1 after 100 cycles at 50 mA g?1, and it remains at 290 mA h g?1 after 600 cycles at 500 mA g?1. Meanwhile, the scientific insight that the formation of stable P? S and P? Ti bonds can provide a guide for the practical large‐scale application of SIBs in other titanium base and black phosphorus materials is looked forward.  相似文献   
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