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Pt-Re/rGO bimetallic catalyst for highly selective hydrogenation of cinnamaldehyde to cinnamylalcohol 被引量:3
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作者 Zuojun Wei Xinmiao Zhu +4 位作者 Xiaoshuang Liu Haiqin Xu Xinghua Li yaxin hou Yingxin Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第2期369-378,共10页
In the present work, a series of Pt-based catalysts, alloyed with a second metal, i.e., Re, Sn, Er, La, and Y, and supported on activated carbon, ordered mesoporous carbon, N-doped mesoporous carbon or reduced graphen... In the present work, a series of Pt-based catalysts, alloyed with a second metal, i.e., Re, Sn, Er, La, and Y, and supported on activated carbon, ordered mesoporous carbon, N-doped mesoporous carbon or reduced graphene oxide(rGO), have been developed for selective hydrogenation of cinnamaldehyde to cinnamylalcohol. Re and rGO were proved to be the most favorable metal dopant and catalyst support, respectively. Pt_(50) Re_(50)/rGO showed the highest cinnamylalcohol selectivity of 89% with 94% conversion of cinnamaldehyde at the reaction conditions of 120 °C, 2.0 MPaH_2 and 4 h. 展开更多
关键词 CATALYST HYDROGENATION SELECTIVITY CINNAMALDEHYDE BIMETAL Reduced Graphene OXIDE
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纳米酶 被引量:13
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作者 范克龙 高利增 +39 位作者 魏辉 江冰 王大吉 张若飞 贺久洋 孟祥芹 王卓然 樊慧真 温涛 段德民 陈雷 姜伟 芦宇 蒋冰 魏咏华 李唯 袁野 董海姣 张鹭 洪超仪 张紫霞 程苗苗 耿欣 侯桐阳 侯亚欣 李建茹 汤国恒 赵越 赵菡卿 张帅 谢佳颖 周子君 任劲松 黄兴禄 高兴发 梁敏敏 张宇 许海燕 曲晓刚 阎锡蕴 《化学进展》 SCIE CAS CSCD 北大核心 2023年第1期1-87,共87页
纳米酶(Nanozymes)是由我国科学家首次提出的新概念,它是一类具有生物催化功能的纳米材料,能够基于特定的纳米结构催化天然酶的底物并作为酶的代替品。自2007年首次报道以来,全球已有来自于55个国家的420多个研究机构证实了纳米酶的普... 纳米酶(Nanozymes)是由我国科学家首次提出的新概念,它是一类具有生物催化功能的纳米材料,能够基于特定的纳米结构催化天然酶的底物并作为酶的代替品。自2007年首次报道以来,全球已有来自于55个国家的420多个研究机构证实了纳米酶的普遍规律。纳米酶的发现第一次揭示纳米材料蕴含一种独特的纳米效应———类酶催化效应。纳米酶作为一种新材料,既有纳米材料本身的理化性质,又有类似酶的催化功能,兼具天然酶与人工酶的优势于一身。其中,纳米结构不仅赋予纳米酶高效催化功能,而且使纳米酶比天然酶稳定,易于规模化生产。另外,纳米酶独特的多酶活性将为设计廉价、稳定、各种各样全新的催化级联反应提供功能分子。纳米酶是多学科交叉融合的典范,2022年被IUPAC评为十大化学新兴技术。在全球从事化学、酶学、材料学、生物学、医学、理论计算等多领域科学家的共同推进下,如今纳米酶已经成为新的研究热点。我国科学家在这一新兴领域一直发挥着引领作用,解析了纳米酶的构⁃效关系,将其催化活性提高了约1万倍,实现了超越天然酶的理性设计,创造了全球首个纳米酶产品,出版了纳米酶学英文专著,发布纳米酶术语及中国/国际标准化。更可喜的是,纳米酶新领域汇集了一大批多学科交叉融合的优秀青年科学家,推动纳米酶进入高速发展阶段,纳米酶的种类已经超过1200多种,其催化机制研究也更加深入,应用研究也从当初的检测逐步拓展到纳米酶催化医学、传感检测、绿色合成、新能源、环境治理等多个领域。本文向读者介绍纳米酶自发现以来的主要进展,包括最近发现的天然纳米酶,期待纳米酶从新概念、新材料衍生出新技术、新产品、新商品,服务人类健康,并带动新学科发展。 展开更多
关键词 纳米酶 酶催化 生物催化 多酶活性
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A MFE method combined with L1-approximation for a nonlinear time-fractional coupled diffusion system
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作者 yaxin hou Ruihan Feng +2 位作者 Yang Liu Hong Li Wei Gao 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2017年第1期179-199,共21页
In this paper,a nonlinear time-fractional coupled diffusion system is solved by using a mixed finite element(MFE)method in space combined with L1-approximation and implicit second-order backward difference scheme in t... In this paper,a nonlinear time-fractional coupled diffusion system is solved by using a mixed finite element(MFE)method in space combined with L1-approximation and implicit second-order backward difference scheme in time.The stability for nonlinear fully discrete finite element scheme is analyzed and a priori error estimates are derived.Finally,some numerical tests are shown to verify our theoretical analysis. 展开更多
关键词 L1-approximation implicit second-order backward difference scheme timefractional coupled diffusion problem stability a priori error analysis
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Auto-CSC:A Transfer Learning Based Automatic Cell Segmentation and Count Framework
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作者 Guangdong Zhan Wentong Wang +2 位作者 Hongyan Sun yaxin hou Lin Feng 《Cyborg and Bionic Systems》 2022年第1期239-248,共10页
Cell segmentation and counting play a very important role in the medical field.The diagnosis of many diseases relies heavily on the kind and number of cells in the blood.convolution neural network achieves encouraging... Cell segmentation and counting play a very important role in the medical field.The diagnosis of many diseases relies heavily on the kind and number of cells in the blood.convolution neural network achieves encouraging results on image segmentation.However,this data-driven method requires a large number of annotations and can be a time-consuming and expensive process,prone to human error.In this paper,we present a novel frame to segment and count cells without too many manually annotated cell images.Before training.we generated the cell image labels on single-kind cell images using traditional algorithms.These images were then used to form the train set with the label.Different train sets composed of different kinds of cell images are presented to the segmentation model to update its parameters.Finally,the pretrained U-Net model is transferred to segment the mixed cell images using a small dataset of manually labeled mixed cell images.To better evaluate the efectiveness of the proposed method,we design and train a new automatic cell segmentation and count framework.The test results and analyses show that the segmentation and count performance of the framework trained by the proposed method equal the model trained by large amounts of annotated mixed cell images. 展开更多
关键词 AUTO IMAGE consuming
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