检索结果-内蒙古大学图书馆

Comparisons and development of electrochemical sensors using G-PANI composite based on filter paper and transparency film substrate

Comparisons and development of electrochemical sensors using...

引用

Nanotechnology 2014: Graphene, CNTs, Particles, Films and Composites - 2014 NSTI Nanotechnology Conference and Expo, NSTI-Nanotech 2014

作者： Ruecha, N. Rodthongkum, N. Cate, D.M. Chailapakul, O. Henry, C.S. Program in Macromolecular Science Faculty of Science Chulalongkorn University Pathumwan Bangkok 10330 Thailand Metallurgy and Materials Science Research Institute Chulalongkorn University Pathumwan Bangkok 10330 Thailand School of Biomedical Engineering Colorado State University Fort Collins CO 80523 United States Electrochemistry and Optical Spectroscopy Research Unit Department of Chemistry Chulalongkorn University Pathumwan Bangkok 10330 Thailand Department of Chemistry Colorado State University Fort Collins CO 80523 United States

ISBN: (纸本)9781482258264

Electrochemical sensors based on filter paper and transparency film substrates have been prepared using screen-printing method for the detection of the heavy metals ions including Pb2+, Cd2+ and Zn 2+. The electrochemical characteristics of these electrodes were analyzed using cyclic voltammetry (CV) and anodic stripping voltammetry (ASV) while the surface roughness were measured using an optical profilometer. For electrochemical characterization by CV, electrodes on paper give a higher current response for ferri/ferrocyanide than transparency-based electrodes. When using ASV for the detection of heavy metals, the transparency-based device gave higher current response than paper-based device. Moreover, for the surface characterization using optical profilometry, carbon ink penetrated into the porous of filter paper but coated on the transparency film substrate affecting to surface roughness in transparency-based electrodes is higher than electrodes on paper. To improve the sensitivity of these devices, graphene (G) and polyaniline (PANI) nanocomposite was prepared by polymerization of aniline monomer in the presence of G and used for electrode modification. G/PANI nanocomposite-modified electrode was characterized by CV and used for heavy metals detection by ASV. This system will be very useful for portable environmental monitoring.

关键词： Graphene

来源：评论

学校读者我要写书评

暂无评论

Gorgon and pathwalking: macromolecular modeling tools for subnanometer resolution density maps

Gorgon and pathwalking: Macromolecular modeling tools for su...

引用

作者： Baker, Matthew L. Baker, Mariah R. Hryc, Corey F. Ju, Tao Chiu, Wah Verna and Marrs McLean Department of Biochemistry and Molecular Biology National Center for Macromolecular Imaging Baylor College of Medicine Houston TX 77030 United States Program in Structural and Computational Biology and Molecular Biophysics Baylor College of Medicine Houston TX 77030 United States Department of Computer Science and Engineering Washington University in St. Louis St. Louis MO 63130 United States

The complex interplay of proteins and other molecules, often in the form of large transitory assemblies, are critical to cellular function. Today, X-ray crystallography and electron cryo-microscopy (cryo-EM) are routinely used to image these macromolecular complexes, though often at limited resolutions. Despite the rapidly growing number of macromolecular structures, few tools exist for modeling and annotating structures in the range of 3-10 Å resolution. To address this need, we have developed a number of utilities specifically targeting subnanometer resolution density maps. As part of the 2010 Cryo-EM Modeling Challenge, we demonstrated two of our latest de novo modeling tools, Pathwalking and Gorgon, as well as a tool for secondary structure identification (SSEHunter) and a new rigid-body/flexible fitting tool in Gorgon. In total, we submitted 30 structural models from ten different subnanometer resolution data sets in four of the six challenge categories. Each of our utlities produced accurate structural models and annotations across the various density maps. In the end, the utilities that we present here offer users a robust toolkit for analyzing and modeling protein structure in macromolecular assemblies at non-atomic resolutions. © 2012 Wiley Periodicals, Inc.

关键词： X ray crystallography

来源：评论

学校读者我要写书评

暂无评论

LED Lights with Hidden Intensity-Modulated Blue Channels Aiming for Enhanced Subconscious Visual Responses

IEEE Photonics Journal

引用

IEEE Photonics Journal 2017年第3期9卷 8201009页

作者： Vartanian, Garen Wong, Kwoon Y. Ku, Pei-Cheng Macromolecular Science and Engineering Graduate Program University of Michigan Ann ArborMI48109 United States Department of Ophthalmology and Visual Sciences University of Michigan Ann ArborMI48109 United States Department of Electrical Engineering and Computer Science University of Michigan Ann ArborMI48109 United States

A new form of light-emitting diode (LED) light suitable for general illumination is proposed to enhance subconscious, nonimage-forming visual responses, which are essential to our well-being. Pulsing light has been shown to reduce photoreceptor adaptation and elicit stronger subconscious visual responses at an indoor illumination level. Using the silent substitution technique, a melanopsin-selective flicker can be added into white light. A linear optimization algorithm was developed to suppress any perceivable fluctuation of light intensity and colors of illuminated objects. Two examples of lights are given to illustrate the potential applications of the proposed multi-LED light for general illumination and therapeutic purposes. © 2009-2012 IEEE.

关键词： Light emitting diodes

来源：评论

学校读者我要写书评

暂无评论

A quantitative assessment of nanoparticle-ligand distributions: Implications for targeted drug and imaging delivery in dendrimer conjugates

A quantitative assessment of nanoparticle-ligand distributio...

引用

作者： Mullen, Douglas G. Fang, Ming Desai, Ankur Baker Jr., James R. Orr, Bradford G. Banaszak Holl, Mark M. Program in Macromolecular Science and Engineering University of Michigan Ann Arbor MI 48109 United States Michigan Nanotechnology Institute for Medicine and Biological Sciences University of Michigan Ann Arbor MI 48109 United States Program in Applied Physics University of Michigan Ann Arbor MI 48109 United States Department of Physics University of Michigan Ann Arbor MI 48109 United States Department of Chemistry University of Michigan Ann Arbor MI 48109 United States

Functional nanoparticles often contain ligands including targeting molecules, fluorophores, and/or active moieties such as drugs. Characterizing the number of these ligands bound to each particle and the distribution of nanoparticle-ligand species is important for understanding the nanomaterial's function. In this study, the amide coupling methods commonly used to conjugate ligands to poly(amidoamine) (PAMAM) dendrimers were examined. A skewed Poisson distribution was observed and quantified using HPLC for two sets of dendrimer-ligand samples prepared using the amine-terminated form of the PAMAM dendrimer and a partially acetylated form of the PAMAM dendrimer that has been used for targeted in vivo drug delivery. The prepared samples had an average number of ligands per dendrimer ranging from 0.4 to 13. Distributions identified by HPLC are in excellent agreement with the mean ligand/dendrimer ratio, measured by 1H NMR, gel permeation chromatography (GPC), and potentiometric titration. These results provide insight into the heterogeneity of distributions that are obtained for many classes of nanomaterials to which ligands are conjugated and belie the use of simple cartoon models that present the "average" number of ligands bound as a physically meaningful representation for the material. © 2010 American Chemical Society.

关键词： Ligands

来源：评论

学校读者我要写书评

暂无评论

AI for organic and polymer synthesis

引用

science China Chemistry 2024年第8期67卷 2461-2496页

作者： Xin Hong Qi Yang Kuangbiao Liao Jianfeng Pei Mao Chen Fanyang Mo Hua Lu Wen-Bin Zhang Haisen Zhou Jiaxiao Chen Lebin Su Shuo-Qing Zhang Siyuan Liu Xu Huang Yi-Zhou Sun Yuxiang Wang Zexi Zhang Zhunzhun Yu Sanzhong Luo Xue-Feng Fu Shu-Li You Center of Chemistry for Frontier Technologies Department of ChemistryZhejiang UniversityHangzhou 310027China Center of Basic Molecular Science Department of ChemistryTsinghua UniversityBeijing 100084China Guangzhou National Laboratory Guangzhou 510005China Center for Quantitative Biology Academy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China School of Materials Science and Engineering Peking UniversityBeijing 100871China Beijing National Laboratory for Molecular Sciences Center for Soft Matter Science and EngineeringKey Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China AI for Science(AI4S)-Preferred Program Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China State Key Laboratory of Chemical Biology Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China Department of Chemical Sciences National Natural Science Foundation of ChinaBeijing 100085China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Recent years have witnessed the transformative impact from the integration of artificial intelligence with organic and polymer synthesis. This synergy offers innovative and intelligent solutions to a range of classic problems in synthetic chemistry. These exciting advancements include the prediction of molecular property, multi-step retrosynthetic pathway planning, elucidation of the structure-performance relationship of single-step transformation, establishment of the quantitative linkage between polymer structures and their functions, design and optimization of polymerization process, prediction of the structure and sequence of biological macromolecules, as well as automated and intelligent synthesis platforms. Chemists can now explore synthetic chemistry with unprecedented precision and efficiency, creating novel reactions, catalysts, and polymer materials under the datadriven paradigm. Despite these thrilling developments, the field of artificial intelligence(AI) synthetic chemistry is still in its infancy, facing challenges and limitations in terms of data openness, model interpretability, as well as software and hardware support. This review aims to provide an overview of the current progress, key challenges, and future development suggestions in the interdisciplinary field between AI and synthetic chemistry. It is hoped that this overview will offer readers a comprehensive understanding of this emerging field, inspiring and promoting further scientific research and development.

关键词： organic synthesis polymer synthesis machine learning prediction chemical database automated synthesis

来源：评论

学校读者我要写书评

暂无评论

Reconffgurable protein matrices for prolonged neuroblasts patterning and retraction

Reconffgurable protein matrices for prolonged neuroblasts pa...

引用

2005 3rd IEEE/EMBS Special Topic Conference on Microtechnology in Medicine and Biology

作者： Zhu, Xiaoyue Mills, Kristen L. Peters, Portia R. Naruse, Keiji Csete, Marie E. Thouless, M.D. Takayama, Shuichi Department of Biomedical Engineering University of Michigan Ann Arbor MI 48109 United States Department of Mechanical Engineering University of Michigan Ann Arbor MI 48109 United States Department of Physiology Nagoya University Graduate School of Medicine Nagoya 466-8550 Japan Department of Anesthesiology Emory University School of Medicine Atlanta GA 30322 United States Department of Materials Science and Engineering University of Michigan Ann Arbor MI 48109 United States Macromolecular Science and Engineering Program University of Michigan Ann Arbor MI 48109 United States

ISBN: (纸本)0780387112

Here we present long-term patterning and response studies of neuro blasts on arrays of extracellular matrix (ECM) protein lines fabricated by cracking a polymer-supported thin film and selectively depositing proteins inside the cracks. Neuroblasts cultured for five days on the protein matrix switched between spreading and retraction upon changing the protein line width. This technique provides a novel tool to pursue further understanding of the basic mechanisms of neuroblast pathfinding on adhesion and morphology. Biomedical device design will also benefit from materials engineered with the reconfigurable protein patterns. © 2005 IEEE.

关键词： Proteins

来源：评论

学校读者我要写书评

暂无评论

Terahertz time-domain polarimetry for generalized anistropic and chiral materials 12

Terahertz time-domain polarimetry for generalized anistropic...

引用

Terahertz, RF, Millimeter, and Submillimeter-Wave Technology and Applications XII 2019

作者： Cheng, Gong Choi, Won Jin Jang, Hee-Jeong Kotov, Nicholas A. Norris, Theodore B. Department of Physics University of Michigan Ann ArborMI48109 United States Center for Ultrafast Optical Science University of Michigan Ann ArborMI48109 United States Department of Materials Science and Engineering University of Michigan Ann ArborMI48109 United States Department of Chemical Engineering University of Michigan Ann ArborMI48109 United States Biointerfaces Institute University of Michigan Ann ArborMI48109 United States Program in Macromolecular Science and Engineering University of MI Ann ArborMI48109 United States Department of Electrical Engineering and Computer Science University of Michigan Ann ArborMI48109 United States

ISBN: (纸本)9781510624764

We have developed two terahertz (THz) polarimetric methodologies based on terahertz time-domain spectroscopy (THz-TDS) incorporating three wire-grid polarizers. They require no change to existing THz-TDS setups and are free of any complicated electronic controls and synchronizations. In addition to the standard quantities measured by THz-TDS such as transmission and optical constants, they provide complete information on the anisotropy and chirality for a generalized material through measurements of the full electric field vector and hence the Jones matrix, and calculating specific quantities. Thus terahertz time-domain polarimetry (THz-TDP) can be considered as an upgrade of the conventional THz-TDS, needed for full characterization of anisotropic and chiral materials. In this paper, we describe the details of the experimental settings, mathematical procedures and property quantifications in these methodologies. We present experimental results on an anisotropic polymer sheet showing the effectiveness of the methods, and preliminary data for chiral DNA molecules for the first time in the THz frequency range. © 2019 SPIE.

关键词： Polarimeters

来源：评论

学校读者我要写书评

暂无评论

Pressure-tunable photonic band gaps in an entropic colloidal crystal

引用

Physical Review Materials 2018年第12期2卷 125201-125201页

作者： Rose K. Cersonsky Julia Dshemuchadse James Antonaglia Greg van Anders Sharon C. Glotzer Macromolecular Science and Engineering Program University of Michigan Ann Arbor Michigan 48109 USA Department of Chemical Engineering University of Michigan Ann Arbor Michigan 48109 USA Department of Physics University of Michigan Ann Arbor Michigan 48104 USA Department of Materials Science and Engineering University of Michigan Ann Arbor Michigan 48109 USA Biointerfaces Institute University of Michigan Ann Arbor Michigan 48109 USA

Materials adopting the diamond structure possess useful properties in atomic and colloidal systems and are a popular target for synthesis in colloids where a photonic band gap is possible. The desirable photonic properties of the diamond structure pose an interesting opportunity for reconfigurable matter: Can we create a crystal able to switch reversibly to and from the diamond structure with a photonic band gap in the visible light range? Drawing inspiration from high-pressure transitions of diamond-forming atomic systems, we design a system of polyhedrally shaped colloidal particles with spherical cores that transitions from diamond to a tetragonal diamond derivative upon a small pressure change. The transition can alternatively be triggered by changing the shape of the particle in situ. We propose that the transition provides a reversible reconfiguration process for a potential new colloidal material and draw parallels between this transition and the phase behavior of the atomic transitions from which we take inspiration.

关键词： Photonic crystals Colloidal crystal Hard sphere colloids

来源：评论

学校读者我要写书评

暂无评论

On sparse identification of complex dynamical systems: a study on discovering influential reactions in chemical reaction networks

arXiv

引用

arXiv 2020年

作者： Harirchi, Farshad Kim, Doohyun Khalil, Omar Liu, Sijia Elvati, Paolo Baranwal, Mayank Hero, Alfred Violi, Angela Department of Electrical Engineering and Computer Science University of Michigan Ann ArborMI48109–2125 United States Department of Mechanical Engineering University of Michigan Ann ArborMI48109–2125 United States Departments of Chemical Engineering Biomedical Engineering Macromolecular Science and Engineering Biophysics Program University of Michigan Ann ArborMI48109–2125 United States

A wide variety of real life complex networks are prohibitively large for modeling, analysis and control. Understanding the structure and dynamics of such networks entails creating a smaller representative network that preserves its relevant topological and dynamical properties. While modern machine learning methods have enabled identification of governing laws for complex dynamical systems, their inability to produce white-box models with sufficient physical interpretation renders such methods undesirable to domain experts. In this paper, we introduce a hybrid black-box, white-box approach for the sparse identification of the governing laws for complex, highly coupled dynamical systems with particular emphasis on finding the influential reactions in chemical reaction networks for combustion applications, using a data-driven sparse-learning technique. The proposed approach identifies a set of influential reactions using species concentrations and reaction rates, with minimal computational cost without requiring additional data or simulations. The new approach is applied to analyze the combustion chemistry of H2 and C3H8 in a constant-volume homogeneous reactor. The influential reactions determined by the sparse-learning method are consistent with the current kinetics knowledge of chemical mechanisms. Additionally, we show that a reduced version of the parent mechanism can be generated as a combination of the significantly reduced influential reactions identified at different times and conditions and that for both H2 and C3H8 fuel, the reduced mechanisms perform closely to the parent mechanisms as a function of the ignition delay time over a wide range of conditions. Our results demonstrate the potential of the sparse-learning approach as an effective and efficient tool for dynamical system analysis and reduction. The uniqueness of this approach as applied to combustion systems lies in the ability to identify influential reactions in specified conditions and times dur

关键词： Learning systems

来源：评论

学校读者我要写书评

暂无评论

A New Data-Driven Sparse-Learning Approach to Study Chemical Reaction Networks

arXiv

引用

arXiv 2017年

作者： Harirchi, Farshad Kim, Doohyun Khalil, Omar Liu, Sijia Elvati, Paolo Hero, Alfred Violi, Angela Department of Electrical Engineering and Computer Science University of Michigan Ann ArborMI48109-2125 United States Department of Mechanical Engineering University of Michigan Ann ArborMI48109-2125 United States Biophysics Program Departments of Chemical Engineering Biomedical Engineering Macromolecular Science and Engineering University of Michigan Ann ArborMI48109-2125 United States

Chemical kinetic mechanisms can be represented by sets of elementary reactions that are easily translated into mathematical terms using physicochemical relationships. The schematic representation of reactions captures the interactions between reacting species and products. Determining the minimal chemical interactions underlying the dynamic behavior of systems is a major task. In this paper, we introduce a novel approach for the identification of the inuential reactions in chemical reaction networks for combustion applications, using a data-driven sparse-learning technique. The proposed approach identifies a set of inuential reactions using species concentrations and reaction rates, with minimal computational cost without requiring additional data or simulations. The new approach is applied to analyze the combustion chemistry of H2andC3H8in a constant-volume homogeneous reactor. The inuential reactions identified by the sparse-learning method are consistent with the current kinetics knowledge of chemical mechanisms. Additionally, we show that a reduced version of the parent mechanism can be generated as a combination of the inuential reactions identified at different times and conditions and that for both H2andC3H8this reduced mechanism performs closely to the parent mechanism as a function of ignition delay over a wide range of conditions. Our results demonstrate the potential of the sparse-learning approach as an effective and efficient tool for mechanism analysis and mechanism reduction. Copyright © 2017, The Authors. All rights reserved.

关键词： Learning systems

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：