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21.
Chang Xin Zhang Chengyu Gao Lan Liu Xiao You Shengping Qi Wei Wang Kang Guo Xin Su Rongxin Lu Han He Zhimin 《天津大学学报(英文版)》2019,25(5):488-496
2,5-Furandicarboxylic acid(FDCA) is a potential biorenewable chemical for applications including plastics, polyamides, drugs, etc. The selective biosynthesis of FDCA from 5-hydroxymethylfurfural(HMF) by a specific enzyme poses a great challenge. In this study, we reported an efficient strategy to produce FDCA from HMF by the tandem biocatalysis of laccase(Cot A-TJ102@UIO-66-NH_2) and Novozym 435. For the first step, a nanoparticle metal–organic framework was synthesized as a carrier to immobilize Cot A-TJ102@UIO-66-NH_2, which was assigned for the production of 5-formyl-2-furancarboxylic acid(FFCA) and featured an enzyme loading of 255.54 mg/g, specific activity of 135.90 U/mg, and solid loading ratio of 99.65%. Under optimal conditions, an ideal FFCA yield of 98.5% was achieved, and the Cot A-TJ102@UIO-66-NH_2 presented a high recycling capacity after 10 cycles. For the second step, Novozym 435 was applied for the further conversion of FFCA into FDCA, presenting a high FDCA yield of 95.5% under the optimized conditions. Novozym 435 also exhibited a high recyclability after eight cycles. As a result, the tandem biocatalysis strategy provided a 94.2% FDCA yield from HMF, indicating its excellence as a method for FDCA production. 相似文献
22.
Young Imm Kang Song Jo Ann Gammel 《The International Journal of Art & Design Education》2011,30(2):266-278
Murals are particularly visually captivating forms of public art due to their size and accessibility. Mural images also capture public attention and provoke viewers to explore layers of meaning and find hidden stories. They are often in places that people come to visit, study, play, congregate and discuss matters that may relate to the content of the mural. To this end, murals can be effective tools for helping communities think about their environmental issues. This article discusses the Mystic River mural project in Somerville, Massachusetts, USA. It addresses how the local art councils, mural artists, local students, community members and non‐profit organisations collaborated to carry out this ongoing mural project. The purpose of this research is to examine how Mystic River eco‐murals were created, what challenges and benefits the eco‐murals provided, how local social concerns were represented through the eco‐murals, how eco‐murals can continue to promote environmental awareness and inspire youth about their community and the local environment, and how the mural can continue to reflect or affect the meaning of the place. This process can serve as an example for other communities that seek to address their environmental concerns through public art. 相似文献
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This study provides a detailed report on the synthesis of spherical activated carbon with mesoporous structure using a soluble low molecular weight phenolic resol precursor through an ammonium alginate assisted sol–gel method. The effects of calcinating temperature and the addition of CaCO_3 as a pore-enlarging agent on texture structure and catalytic performance in isobutane dehydrogenation to isobutene were investigated. Characterization of N_2 sorption,mechanical strength tests,and optical photographs confirmed that the obtained carbon materials had high mechanical strength,a good degree of sphericity,and a large surface area. Introducing CaCO_3 as a pore-enlarging agent during the preparation process promoted the formation of a mesoporous structure of carbon spheres and evidently increased the surface area and oxygen content,which can improve isobutane conversion and isobutene selectivity of these carbon spheres. The conversion of isobutane reached up to 28% for this spherical activated carbon,and the selectivity of isobutene reached up to 96%. Isobutane conversion increased with an increase in calcination temperature due to an increase in the oxygen content,whereas the selectivity of isobutene decreased due to the slight decrease in the specific surface area. 相似文献
25.
康壮苏 《呼伦贝尔学院学报》2006,14(5):75-77
文章论述了构建区域科技创新体系应遵循的基本原则,并根据相关原则及各子系统的功能和相互关系构筑了区域科技创新体系组织结构的框架模型,即认为:区域科技创新体系包括两个层次、六个子系统。最后提出了推进区域科技创新体系建设的一些对策措施。 相似文献
26.
曹康 《乌鲁木齐成人教育学院学报》2004,12(2):63-64
随着与国际社会交流机会的增多.英语水平成为衡量学生能力的一个重要方面,英语教学是高等职业技术学院教育中十分重要的一部分。当前,高职生英语基础较差.在专业英语授课过程中要强调同步复习这一环节。 相似文献
27.
通过对Windows内存结构及进程空间分配情况的介绍,详细描述了Win2000环境下缓冲区溢出的原理,并提出了预防缓冲区溢出的有效方法。 相似文献
28.
基于改进的DTW算法的仿真与分析 总被引:2,自引:0,他引:2
传统的DTW算法着重于时间规整和间距测量的概念,对数据的可靠性没有进行有效的分析,且对连续词的识别效果不明显。基于松弛起始点和分段思想的改进DTW算法,可以改善明阿算法的缺陷。通过对语音样本0.9在MATLAB6.5上的仿真实现与分析表明,采用改进后的DTW算法具有良好的语音识别效果。 相似文献
29.
文章分析了汉语迁移对英语学习的正负效应,主要从母语迁移对语音与词汇习得两个方面阐述.语音方面主要分析了英语与汉语在发音方式上的差异,词汇方面主要分析了拼写、词性、词义、搭配等四个方面.研究母语迁移可以分析利用正迁移的有利作用,对负迁移提出解决对策,从而促进中国学生的英语学习. 相似文献
30.
康双珍 《中国远程教育(综合版)》2002,(11):66-67
本文就信息技术与语文教育一体化进行了粗略地描绘以计算机为"课堂",拓展语文学习领域;以计算机为"教材",拓展语文学习内容;以计算机为"工具",拓展语文学习方式.借此说明如何科学认识和把握信息技术在语文教育中的作用以及对语文教育变革的方向,加快信息技术与语文教育的"一体化"进程. 相似文献