检索结果-内蒙古大学图书馆

Review of Cellulose Nanocrystal-based Fluorophore Materials and Their Application in Metal Ion Detection

Paper And Biomaterials 2018年第4期3卷 45-61页

作者： Ya Wang Alain Dufresne Peter R. Chang XiaoZhou Ma Jin Huang School of Chemistry and Chemical Engineering Joint International Research Laboratory of Biomass-Based Macromolecular Chemistry and Materials Southwest University Chongqing 400715 China Université Grenoble Alpes CNRS Grenoble INP LGP2 F-38000 Grenoble France Bioproducts and Bioprocesses National Science Program Agriculture and Agri-Food Canada 107 Science Place Saskatoon SK S7N0X2 Canada

Cellulose nanocrystals （CNCs）, a unique and promising natural material extracted from native cellulose, have attracted considerable attention owing to their physical properties and special surface chemistry. This review focuses on chemical conjugation strategies that can be used for preparation of ？uorescent-molecule labeled CNCs and the development of biomaterials. Furthermore, their application in the detection of metal ions and future development prospects are discussed. We hope to provide a clear view of the strategies for surface fluorescent modifcation of CNCs and their application in detection of metal ions.

关键词： fluorescent cellulose nanocrystals detection of metal ions sensors optical imaging biomaterial

来源：评论

学校读者我要写书评

暂无评论

Biased Lewis Pairs: A General Catalytic Approach to Ether‐Ester Block Copolymers with Unlimited Ordering of Sequences

引用

Angewandte Chemie 2019年第43期131卷

作者： Shan Liu Tianwen Bai Kang Ni Ye Chen Junpeng Zhao Jun Ling Xiaodong Ye Guangzhao Zhang Faculty of Materials Science and Engineering South China University of Technology Guangzhou 510640 P. R. China MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemical Physics University of Science and Technology of China Hefei 230026 China

Polymerizing epoxides after cyclic esters remains a major challenge, though their block copolymers have been extensively studied and used for decades. Reported here is a simple catalytic approach based on a metal‐free Lewis pair that addresses the challenge. When the Lewis acid is used in excess of a base, selective (transesterification‐free) polymerization of epoxides occurs in the presence of esters, while selectivity toward cyclic esters is achieved by an oppositely biased catalyst. Hence, one‐pot block copolymerization can be performed in both ester‐first and ether‐first orders with selectivity being switchable at any stage, yielding ether‐ester‐type block copolymers with unlimited ordering of sequences as well as widely variable compositions and architectures. The selectivity can also be switched back and forth several times to generate a multiblock copolymer. Experimental and calculational results indicate that the selectivity originates mainly from the state of catalyst‐activated hydroxy species.

关键词： Chemoselektivität Lewis-Säuren Organokatalyse Polymere Ringöffnung

来源：评论

学校读者我要写书评

暂无评论

Transient heat transfer in a packed-bed elliptic cylindrical reactor: A finite-volume approach

引用

Defect and Diffusion Forum 2017年第1期380卷 79-85页

作者： Moura da Silva, R. Barbosa de Lima, A.G. Gomes de Oliveira, L. Vasconcellos Araújo, M. Sousa Santos, R. Federal University of Campina Grande Center of Science and Technology Process Engineering Postgraduate Program Campina Grande Paraíba58429-900 Brazil Federal Institute of Education Science and Technology of Paraíba Princesa Isabel Paraíba58755-000 Brazil Federal University of Campina Grande Center of Science and Technology Mechanical Engineering Department Campina Grande Paraíba58429-900 Brazil Federal University of Campina Grande Center of Science and Technology Chemical Engineering Department Campina Grande Paraíba58429-900 Brazil

This work aims to develop a transient three-dimensional mathematical model using the elliptic cylindrical coordinate system, to predict heat transfer in a elliptic cylindrical packed fixed bed reactor. The model considers variable thermo physical properties and a parabolic temperature profile at the fluid inlet. The governing equation is solved using the finite volume method. Results of temperature profile along the reactor are presented and discussed at different *** was verified that the maximum heat transfer rate inside the reactor occurs near the extreme region close to minor semi-axis of the ellipse;the higher temperatures at the reactor surface are also in this region, along the entire height of the bed;the steady-state regime is reached at t = 4.5 s of process, presenting after this time interval,small axial temperature gradients and high radial gradients along of the reactor bed;the parabolic temperature profile give to the bed a predominance of radial temperature gradients, and the radial porosity profile favours a higher heat transfer rate at reactor surface. © 2017 Trans Tech Publications, Switzerland

关键词： Heat transfer

来源：评论

学校读者我要写书评

暂无评论

Enhanced hydrogen production activity over BiOX–TiO2 under solar irradiation:Improved charge transfer through bismuth oxide clusters

引用

Journal of Energy Chemistry 2017年第3期26卷 390-397页

作者： Police Anil Kumar Reddy Chennaiahgari Manvitha Pullagurala Venkata Laxma Reddy Ki-Hyun Kim Valluri Durga Kumari Department of Civil&Environmental Engineering Hanyang University222WangsimniRoSeoul 133-791Republic of Korea Inorganic and Physical Chemistry Division Indian Institute of Chemical TechnologyHyderabad 500 607India Sarojini Naidu Vanitha Mahavidyala Osmania UniversityHyderabad 500 001India Program in Environmental Science and Engineering University of Texas El PasoEl PasoTexas 799038USA

A series of titania nanoparticles and nanotubes deposited with various quantities of bismuth（Bi） were prepared via sol-gel and hydrothermal methods, respectively. They were then characterized using X-ray diffraction spectroscopy（XRD）, X-ray photo electron spectroscopy（XPS）, UV–Vis diffused reflectance spectra（DRS）, photoluminescence spectra（PLS）, transmission electron microscopy（TEM）, energy dispersive analysis of X-rays（EDAX）, and BET surface analysis. These catalysts were employed for the photocatalytic production of hydrogen from a mixture of pure water and glycerol under solar light irradiation. The presence of the Bispecies was found to play a vital role in enhancing activity while minimizing electron hole recombination（relative to bare TiO）. The nanotubes exhibited better activity than the nanoparticles of Bi-deposited TiO, showing the significance of the morphology; however, photocatalytic activity is predominantly dependent on the deposition of bismuth. The activity increased by approximately an order of magnitude at the optimum concentration of Bi deposited over TiO（2 wt%）. The presence of the Bispecies played a vital role in minimizing electron hole recombination, resulting in higher activity compared to bare TiO.

关键词： Bismuth TiO2 nanotubes Visible photocatalysis Water splitting Hydrogen

来源：评论

学校读者我要写书评

暂无评论

Bacterial Polyesters: Microbial Polyhydroxyalkanoates and Nonnatural Polyesters (Adv. Mater. 35/2020)

引用

Advanced Materials 2020年第35期32卷

作者： So Young Choi In Jin Cho Youngjoon Lee Yeo‐Jin Kim Kyung‐Jin Kim Sang Yup Lee Metabolic and Biomolecular Engineering National Research Laboratory Systems Metabolic Engineering and Systems Healthcare Cross‐Generation Collaborative Laboratory Department of Chemical and Biomolecular Engineering (BK21 Plus Program) Institute for the BioCentury Korea Advanced Institute of Science and Technology (KAIST) 291 Daehak‐ro Yuseong‐gu Daejeon 34141 Republic of Korea School of Life Sciences (KNU Creative BioResearch Group) KNU Institute for Microorganisms Kyungpook National University 80 Daehak‐ro Buk‐gu Daegu 41566 Republic of Korea BioProcess Engineering Research Center and Bioinformatics Research Center Korea Advanced Institute of Science and Technology (KAIST) 291 Daehak‐ro Yuseong‐gu Daejeon 34141 Republic of Korea

来源：评论

学校读者我要写书评

暂无评论

Probing hyperbolic polaritons using infrared attenuated total reflectance micro-spectroscopy

arXiv

引用

arXiv 2018年

作者： Folland, Thomas G. Maß, Tobias W.W. Matson, Joseph R. Ryan Nolen, J. Liu, Song Watanabe, Kenji Taniguchi, Takashi Edgar, James H. Taubner, Thomas Caldwell, Joshua D. Department of Mechanical Engineering Vanderbilt University NashvilleTN37212 United States RWTH Aachen University Aachen52056 Germany Interdisciplinary Materials Science Program Vanderbilt University NashvilleTN37212 Department of Chemical Engineering Kansas State University ManhattanKS66506 United States National Institute for Materials Science Tsukuba Japan

Hyperbolic polariton modes are highly appealing for a broad range of applications in nanophotonics, including surfaced enhanced sensing, sub-diffractional imaging and reconfigurable metasurfaces. The existence of this type of mode depends on extreme anisotropy in the optical properties of a natural or artificial material. However, due to their high in-plane momentum (short polariton wavelength), these hyperbolic polaritons cannot be launched by light propagating in free space. Here we show that attenuated total reflectance micro-spectroscopy (ATR) using standard spectroscopic tools can launch hyperbolic polaritons in a Kretschmann-Raether configuration. We measure multiple hyperbolic and dielectric modes within the naturally hyperbolic material hexagonal boron nitride as a function of different isotopic enrichments and flake thickness. This overcomes the technical challenges of measurement approaches based on nanostructuring, or scattering scanning nearfield optical microscopy. Ultimately, our ATR approach allows us to compare the optical properties of small-scale materials prepared by different techniques systematically. Copyright © 2018, The Authors. All rights reserved.

关键词： Photons

来源：评论

学校读者我要写书评

暂无评论

Quantitative Design of Bright Fluorophores and AIEgens by the Accurate Prediction of Twisted Intramolecular Charge Transfer (TICT)

引用

Angewandte Chemie 2020年第25期132卷

作者： Chao Wang Qinglong Qiao Weijie Chi Jie Chen Wenjuan Liu Davin Tan Scott McKechnie Da Lyu Xiao‐Fang Jiang Wei Zhou Ning Xu Qisheng Zhang Zhaochao Xu Xiaogang Liu Fluorescence Research Group Singapore University of Technology and Design 8 Somapah Road Singapore 487372 Singapore CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical Physics Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China Department of Physics Kings College London London WC2R 2LS UK Department of Chemistry National University of Singapore 21 Lower Kent Ridge Rd Singapore 119077 Singapore School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China

Inhibition of TICT can significantly increase the brightness of fluorescent materials. Accurate prediction of TICT is thus critical for the quantitative design of high‐performance fluorophores and AIEgens. TICT of 14 types of popular organic fluorophores were modeled with time‐dependent density functional theory (TD‐DFT). A reliable and generalizable computational approach for modeling TICT formations was established. To demonstrate the prediction power of our approach, we quantitatively designed a boron dipyrromethene (BODIPY)‐based AIEgen which exhibits (almost) barrierless TICT rotations in monomers. Subsequent experiments validated our molecular design and showed that the aggregation of this compound turns on bright emissions with ca. 27‐fold fluorescence enhancement, as TICT formation is inhibited in molecular aggregates.

关键词： Aggregationsinduzierte Emission BODIPY Molekül-engineering PRODAN Intramolekularer Ladungstransfer

来源：评论

学校读者我要写书评

暂无评论

High‐Performance K–CO2Batteries Based on Metal‐Free Carbon Electrocatalysts

引用

Angewandte Chemie 2019年第9期132卷

作者： Wenchao Zhang Chuangang Hu Zaiping Guo Liming Dai Institute for Superconducting and Electronic Materials (ISEM) School of Mechanical Materials Mechatronics and Biomedical Engineering Faculty of Engineering and Information Sciences University of Wollongong Wollongong NSW 2500 Australia Center of Advanced Science and Engineering for Carbon (Case4Carbon) Department of Macromolecular Science and Engineering Case Western Reserve University 10900 Euclid Avenue Cleveland OH 44106 USA The UNSW-CWRU International Joint Laboratory School of Chemical Engineering University of New South Wales Sydney Australia

Metal–CO 2 batteries have attracted much attention owing to their high energy density and use of greenhouse CO 2 waste as the energy source. However, the increasing cost of lithium and the low discharge potential of Na–CO 2 batteries create obstacles for practical applications of Li/Na–CO 2 batteries. Recently, earth‐abundant potassium ions have attracted considerable interest as fast ionic charge carriers for electrochemical energy storage. Herein, we report the first K–CO 2 battery with a carbon‐based metal‐free electrocatalyst. The battery shows a higher theoretical discharge potential ( E ⊖ =2.48 V) than that of Na–CO 2 batteries ( E ⊖ =2.35 V) and can operate for more than 250 cycles (1500 h) with a cutoff capacity of 300 mA h g −1 . Combined DFT calculations and experimental observations revealed a reaction mechanism involving the reversible formation and decomposition of P 12 1 / c 1‐type K 2 CO 3 at the efficient carbon‐based catalyst.

关键词： Batterien Kohlendioxid Kohlenstoffnanoröhren Elektrokatalyse Graphenoxid

来源：评论

学校读者我要写书评

暂无评论

Hierarchically Porous Carbon Membranes Derived from PAN and Their Selective Adsorption of Organic Dyes

引用

Chinese Journal of Polymer science 2016年第1期34卷 23-33页

作者：吴青芸 Hong-qing Liang Meng Li Bo-tong Liu 徐志康 Department of Polymer Science and Engineering Faculty of MaterialsScience and Chemical EngineeringNingbo UniversityNingbo 315211China MOE Key Laboratory of Macromolecular Synthesis andFunctionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

Porous carbon membranes were favorably fabricated through the pyrolysis of polyacrylonitrile（PAN） precursors, which were prepared with a template-free technique-thermally induced phase separation. These carbon membranes possess hierarchical pores, including cellular macropores across the whole membranes and much small pores in the matrix as well as on the pore walls. Nitrogen adsorption indicates micropores（1.47 and 1.84 nm） and mesopores（2.21 nm） exist inside the carbon membranes, resulting in their specific surface area as large as 1062 m2/g. The carbon membranes were used to adsorb organic dyes（methyl orange, Congo red, and rhodamine B） from aqueous solutions based on their advantages of hierarchical pore structures and large specific surface area. It is particularly noteworthy that the membranes present a selective adsorption towards methyl orange, whose molecular size（1.2 nm） is smaller than those of Congo red（2.3 nm） and rhodamine B（1.8 nm）. This attractive result can be attributed to the steric structure matching between the molecular size and the pore size, rather than electrostatic attraction. Furthermore, the used carbon membranes can be easily regenerated by hydrochloric acid, and their recovery adsorption ratio maintains above 90% even in the third cycle. This work may provide a new route for carbon-based adsorbents with hierarchical pores via a template-free approach, which could be promisingly applied to selectively remove dye contaminants in aqueous effluents.

关键词： Carbon membranes Polyacrylonitrile Thermally induced phase separation Methyl orange Selective adsorption

来源：评论

学校读者我要写书评

暂无评论

Correction: The long and short non-coding RNAs modulating EZH2 signaling in cancer

引用

Journal of hematology & oncology 2022年第1期15卷 50页

作者： Sepideh Mirzaei Mohammad Hossein Gholami Kiavash Hushmandi Farid Hashemi Amirhossein Zabolian Israel Canadas Ali Zarrabi Noushin Nabavi Amir Reza Aref Francesco Crea Yuzhuo Wang Milad Ashrafizadeh Alan Prem Kumar Department of Biology Faculty of Science Islamic Azad University Science and Research Branch Tehran Iran. Faculty of Veterinary Medicine Kazerun Branch Islamic Azad University Kazerun Iran. Department of Food Hygiene and Quality Control Division of Epidemiology and Zoonoses Faculty of Veterinary Medicine University of Tehran Tehran Iran. Department of Comparative Biosciences Faculty of Veterinary Medicine University of Tehran Tehran *** Iran. Department of Orthopedics School of Medicine 5Th Azar Hospital Golestan University of Medical Sciences Gorgan Golestan Iran. Blood Cell Development and Function Program Fox Chase Cancer Center Philadelphia PA USA. Department of Biomedical Engineering Faculty of Engineering and Natural Sciences Istinye University Istanbul 34396 Turkey. Department of Urological Sciences and Vancouver Prostate Centre University of British Columbia Vancouver BC V6H3Z6 Canada. Belfer Center for Applied Cancer Science Dana-Farber Cancer Institute Harvard Medical School Boston MA USA. Department of Translational Sciences Xsphera Biosciences Inc. Boston MA USA. Cancer Research Group-School of Life Health and Chemical Sciences The Open University Walton Hall Milton Keynes MK7 6AA UK. Department of Urological Sciences and Vancouver Prostate Centre University of British Columbia Vancouver BC V6H3Z6 Canada. ywang@bccrc.ca. Faculty of Engineering and Natural Sciences Sabanci University Orta Mahalle Üniversite Caddesi No. 27 Orhanlı Tuzla Istanbul 34956 Turkey. milad.ashrafizadeh@sabanciuniv.edu. Department of Pharmacology Yong Loo Lin School of Medicine National University of Singapore Singapore 117599 Singapore. apkumar@nus.edu.sg. NUS Centre for Cancer Research (N2CR) Yong Loo Lin School of Medicine National University of Singapore Singapore Singapore. apkumar@nus.edu.sg.

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：