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本文介绍间苯氧基苯甲醛产品及其原料的GC/MS分析。该系列化合物和它的衍生物的质谱均出现较强的分子离子峰,文中列出了检测到的十六种化合物,并根据基峰的变化确定氯原子取代的位置是在苯环上或是取代在甲基上。此外,还对间苯氧基苯甲醛生产过程中存在的副反应进行了推导,给出三类副反应式,并在GC/MS实验结果中得到证实。 相似文献
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对承受任意水平荷载的对称式高层单跨框架和双肢剪力墙,进行了统一的内力分析,并针对其力法方程组的特性,提出了两种既可靠又经济的便捷解法 相似文献
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文章从金融危机的本质以及对其他实体经济的影响出发,通过分析美国次贷危机的形成和发展,金融衍生品在危机当中的作用,解释了目前世界金融危机产生的根本原因,希望对我国金融企业健康发展和金融创新产品的设计生产起到警示和提醒作用. 相似文献
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锂离子电池正极材料锰酸锂派生物LiMn1.75Me0.25O4(Me=Ti, Fe, Ni)的制备与表征 总被引:3,自引:1,他引:3
在合成纯相尖晶石型锰酸锂的基础上 ,采用固相分段法制备了锰酸锂派生物LiMn1.75Ti0 .2 5O4 ,LiMn1.75Fe0 .2 5O4 和LiMn1.75Ni0 .2 5O4 。用XRD ,SEM和粒度测试仪分别对试样进行了表征。电化学检测表明 ,Fe和Ni元素能够提高锰酸锂的放电平台电压 ,Ti元素不能改善锰酸锂的电化学性能。从结构化学角度初步探讨了Fe ,Ni和Ti元素对纯相尖晶石型锰酸锂结构的影响。 相似文献
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Ke Zhang Dehuan Meng Feiming Bai Junyi Zhai Zhong Lin Wang 《Advanced functional materials》2020,30(34)
Memristor‐based architectures have shown great potential for developing future computing systems beyond the era of von Neumann and Moore's law. However, the monotonous electrical input for dynamic resistance regulation limits the developments of memristors. Here, a concept of a photon‐memristive system, which realizes memristance depending on number of photons (optical inputs), is proposed. A detailed theoretical derivation is performed and the memristive characteristics, as stimulated by the optical inputs based on a hybrid system, consisting of a low‐dimension photoelectric semiconductor and a ferroelectric substrate are determined. The photon‐memristive system is also suitable for nonvolatile photonic memory since it possesses three or more‐bit data storage, desirable resistance‐change space, and an ON/OFF ratio of nearly 107. The integrated circuit based on several photon‐memristive systems also realizes available photon‐triggered in‐memory computing. The photon‐memristive system expands the definition of memristors and emerges as a new data storage cell for future photonic neuromorphic computational architectures. 相似文献
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设U=Tri(A,M,B)是三角代数,引入三角代数U上的Jordan导子和内导子的概念,利用算子论的方法证明三角代数U上的Jordan导子是三角代数U上的内导子。从而推广了三角代数U上的Jordan导子的定义。 相似文献
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《国际计算机数学杂志》2012,89(6):1156-1169
In this paper, we address several open problems concerning pure grammar systems (pGSs) and their controlled versions. More specifically, we prove the following four results. (I) Regular-controlled pGSs having a single component define the family of regular languages. (II) pGSs having two components controlled by infinite regular languages define the family of recursively enumerable languages. (III) Regular-controlled pGSs without any erasing rules define the family of regular languages not containing the empty string. (IV) pGSs define a proper subfamily of the family of regular languages. 相似文献
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