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991.
废旧电池中有价金属回收利用探讨 总被引:1,自引:0,他引:1
随着中国经济的稳步发展和投资环境的不断优化,中国已成为电池的制造和消费大国,每年产生数亿只废旧电池。对废旧电池的回收利用已成为全社会关注的问题。介绍了废旧电池中有价金属的回收利用方法,着重介绍了锂离子二次电池正极材料有价金属的回收利用方法。指出,中国商品化的正极材料只有钴酸锂(LiCoO2),这种正极材料钴含量高,且钴价值高,并且回收工艺可行,因此,从钴酸锂正极材料中回收钴等有价金属,对发展中国的循环经济具有重要意义。同时介绍了锂离子二次电池正极材料的研究现状。 相似文献
992.
The molecular orientation at the outer surface of injection–stretch–blow‐molded bottles made from poly(ethylene terephthalate) was characterized and quantified by means of front‐surface reflection infrared spectroscopy based on a method developed previously. Results were obtained for two different bottle shapes (cylindrical and rectangular) molded at different injection mold temperatures (16, 38, and 60°C). For the cylindrical bottles, the preferred molecular chain orientation was found to be in the axial direction, with the Hermans orientation function near 0.3 for all three mold temperatures. For the less symmetrical rectangular bottles, a significant difference was observed between the large and small faces. For the large face, the orientation was mainly in the hoop direction; the Hermans orientation function was in the range of 0.3–0.5 and was essentially the same at all mold temperatures and positions along the bottle height. For the small face, on the other hand, the preferred orientation changed from the hoop direction near the bottom to the axial direction near the top, and the variation was more pronounced at lower mold temperatures. The utility of the front‐surface reflection technique was clearly demonstrated. It was also applied, with the use of an infrared microscope, to examine the orientation gradient across the wall thickness. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1319–1327, 2007 相似文献
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在交流条件硅酸钠溶液中利用微等离子体氧化技术合成了陶瓷涂层。通过XRD,EPMA分析了所得陶瓷涂层在不同层面上的相组成、微观结构及元素分布。由陶瓷涂层截面的背散射图看出陶瓷涂层较致密、与基体结合强度高。XRD分析结果显示,陶瓷涂层的最外层由莫来石及γ-Al2O3相组成,随着向陶瓷涂层内部的移动,莫来石的含量逐渐减少,α-Al2O3,γ-A12O3相的含量逐渐提高,而且陶瓷涂层的颜色由白色逐渐变为黑色。硅元素在陶瓷涂层的外侧及陶瓷涂层与基体的交界处陶瓷涂层一侧含量较多,在陶瓷涂层中间含量少。而陶瓷涂层的硬度变化也出现了中间高,两侧低的分布情况。 相似文献
996.
C10芳烃的开发利用 总被引:2,自引:0,他引:2
C10芳芳烃资源集中,用途广泛,蕴茂着巨大经济效益。C10芳烃的开发已引起国内外的重视。本文重点概述了国内我生产技术和今后发展趋势,以及C10芳烃综合利用的经济效益,为C10芳烃的开发利用提供可参考的意见。 相似文献
997.
J. J. Ben⩼ez M. A. Centeno J. A. Odriozola R. Conanec R. Marchand Y. Laurent 《Catalysis Letters》1995,34(3-4):379-388
XPS and DRIFTS (diffuse reflectance infrared spectroscopy) spectra of AlPO systems, formally AlPO4-Al2O3, obtained by the sol-gel method have been studied in order to understand their geometric and electronic structure. Both DRIFTS and XPS demonstrate that the acidbase character of these samples depends on a structural modification. For low phosphorus content an amorphous spinel-like solid is proposed. This geometric arrangement alters the electronic density of oxide ions and phosphorus cations and hence their Lewis acid-base properties with respect to the amorphous solid having aluminium and phosphorus only in tetrahedral arrangement. 相似文献
998.
YAO Suwei LI He ZHANG Weiguo WANG Hongzhi and BEN Yuheng SUGIYAMA Laboratory of Surface Technology School of Chemical Engineering Technology Tianjin University Tianjin China 《稀有金属(英文版)》2006,25(3):241-245
1. Introduction Because of the fast development of the modern industry in the last century, the reserves of fossil en-ergy resources, such as oil, natural gas, and coal, were reduced rapidly. In addition, the contamination of global environment aggravated because of the industrial growth. To overcome these problems and to find a source of renewable energy, scientists have extensively studied the utilization of hydrogen en-ergy for several decades, which is harmless to the environment [1]. Fuji… 相似文献
999.
Ramesa Shafi BHAT Amina El GEZEERY Abir Ben BACHAN Mona Awad ALONAZI Leena Saleh ALSUHAIBANI Afaf El-ANSARY 《Biocell》2019,43(2):65-71
Fluoride is a key ingredient of many psychiatric drugs like fluoxetine (Prozac®, Fluoxetine®). Pregnant womenfrequently use this drug as they suffer from depression and anxiety disorders during this period. Fluoxetine is able toreach the fetus through the placenta and passes to the newborn through milk. In the present study, female Wistar ratswere treated with 5, 10, and 20 mg/L fluoxetine (containing 94% fluorides) from pregnancy day 10 to day 20. Afterdelivery, the levels of the enzymatic antioxidants in the brain of their offspring at postnatal day 2 were measured. Theresults showed that, in all fluoxetine exposed groups compared with the control group, there was a significant decrease(P < 0.01) in the glutathione, catalase, glutathione S-transferases and potassium and a non- significant increase (P >0.05) in the activity of malondialdehyde and creatine kinase. The results suggest that fluoxetine may be a developmentalneurotoxicant due to presence of fluoride hence must be used carefully during pregnancy. 相似文献
1000.
The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods.... 相似文献