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A route to hierarchical assembly of colloidal diamond

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arXiv 2021年

作者： Zhou, Yuan Cersonsky, Rose K. Glotzer, Sharon C. Department of Chemical Engineering University of Michigan Ann ArborMI48109 United States Macromolecular Science and Engineering Program University of Michigan Ann ArborMI48109 United States Laboratory of Computational Science and Modelling STI Ècole Polytechnique Fèdèrale de Lausanne Lausanne1015 Switzerland Biointerfaces Institute University of Michigan Ann ArborMI48109 United States

Photonic crystals, appealing for their ability to control light, are constructed by periodic regions of different dielectric constants. Yet, the structural holy grail in photonic materials, diamond, remains challenging to synthesize at the colloidal length scale. Here we explore new ways to assemble diamond using modified gyrobifastigial (mGBF) nanoparticles, a shape that resembles two anti-aligned triangular prisms. We investigate the parameter space that leads to the self-assembly of diamond, and we compare the likelihood of defects in diamond self-assembled via mGBF vs. the nanoparticle shape that is the current focus for assembling diamond, the truncated tetrahedra. We introduce a potential route for realizing mGBF particles by dimerizing triangular prisms using attractive patches, and we report the impact of this superstructure on the photonic properties. Copyright © 2021, The Authors. All rights reserved.

关键词： Diamonds

A Binary Silicon-Centered Organoboron Catalyst with Superior Performance to That of Its Bifunctional Analogue

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Angewandte Chemie 2023年第48期135卷

作者： Cheng-Kai Xu Guan-Wen Yang Chenjie Lu Prof. Dr. Guang-Peng Wu MOE Key Laboratory of Macromolecular Synthesis and Functionalization Key Laboratory of Adsorption and Separation Materials and Technologies of Zhejiang Province Department of Polymer Science and Engineering Zhejiang University Yuhangtang Road 866 Hangzhou 310058 China College of Material Chemistry and Chemical Engineering Key Laboratory of Organosilicon Chemistry and Material Technology Ministry of Education Hangzhou Normal University Hangzhou 311121 China

This work reported that a silicon-centered alkyl borane/ammonium salt binary (two-component) catalyst exhibits much higher activity than its bifunctional analogue (one-component) for the ring-opening polymerization of propylene oxide, showing 7.3 times the activity of its bifunctional analogue at a low catalyst loading of 0.01 mol %, and even 15.3 times the activity at an extremely low loading of 0.002 mol %. By using 19 F NMR spectroscopy, control experiments, and theoretical calculation we discovered that the central silicon atom displays appropriate electron density and a larger intramolecular cavity, which is useful to co-activate the monomer and to deliver propagating chains, thus leading to a better intramolecular synergic effect than its bifunctional analogue. A unique two-pathway initiation mode was proposed to explain the unusual high activity of the binary catalytic system. This study breaks the traditional impression of the binary Lewis acid/nucleophilic catalyst with poor activity because of the increase in entropy.

关键词： Boron Catalysts Ethers Polymerization Silicon

Modeling the Effect of Over-discharge Cycling on Li-ion Batteries

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Journal of The Electrochemical Society 2025年第5期172卷 050534-050534页

作者： Raghav Sai Thiagarajan Anthony Concepción Deepti Tewari Judith A. Jeevarajan Vinay Premnath Venkat R. Subramanian Materials Science and Engineering Program Texas Materials Institute The University of Texas at Austin Austin Texas 78712 United States of America Walker Department of Mechanical Engineering & Material Science Engineering Texas Materials Institute The University of Texas at Austin Austin Texas 78712 United States of America Electrochemical Safety Research Institute UL Research Institutes 5000 Gulf Fwy UHTB Houston Texas 77204 United States of America Affiliate Faculty Oden Institute for Computational Science and Engineering The University of Texas at Austin Austin Texas 78712 United States of America

Off-nominal circumstances inducing cell over-discharge in a battery are of concern due to electrolyte decomposition and prolonged degradation effects. Copper dissolution and its subsequent deposition could lead to high cell temperatures and, in some cases, catastrophic failures during the battery's operational lifetime. Extending physics-based lithium-ion battery models for the purpose of simulating over-discharge conditions require key considerations in model parameters, constitutive equations, and the state of charge window of operation. This paper reports a reduced-order model for over-discharge and simulating its effect under various scenarios using a thermal tanks-in-series (TTiS) approach. The model was used to compare voltage-time behavior and capacity fade during cycling for different over-discharge cycling protocols. The efficacy of cycling simulations was validated with experimental data, and the TTiS model demonstrates reasonable agreement with the voltage, temperature, and capacity fade trends under the given experimental cycling regimes.

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Chemical evolution of some selected complex organic molecules in low-mass star-forming regions

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arXiv 2023年

作者： Bhat, Bratati Kar, Rumela Mondal, Suman Kumar Ghosh, Rana Gorai, Prasanta Shimonishi, Takashi Tanaka, Kei E.I. Furuya, Kenji Das, Ankan Institute of Astronomy Space and Earth Science 1 Bidhan Sishu Sarani Kolkata700054 India Department of Metallurgical Engineering and Material Sciences IIT Bombay Powai Maharashtra Mumbai400076 India S. N. Bose National Center for Basic Sciences JD-Block Salt Lake Kolkata700098 India Indian Centre for Space Physics 43 Chalantika Garia Station Road Kolkata700084 India Department of Space Earth & Environment Chalmers University of Technology GothenburgSE-412 96 Sweden Center for Transdisciplinary Research Niigata University Niigata Nishi-ku950-2181 Japan Environmental Science Program Department of Science Faculty of Science Niigata University Niigata Nishi-ku950-2181 Japan Department of Earth and Planetary Sciences Tokyo Institute of Technology Meguro Tokyo152-8551 Japan Center for Computational Sciences University of Tsukuba Tsukuba305-8577 Japan National Astronomical Observatory of Japan Tokyo181-8588 Japan

The destiny of complex organic molecules (COMs) in star-forming regions is interlinked with various evolutionary phases. Therefore, identifying these species in diversified environments of identical star-forming regions would help to comprehend their physical and chemical heritage. We identified multiple COMs utilizing the Large program ‘Astrochemical Surveys At IRAM’ (ASAI) data, dedicated to chemical surveys in Sun-like star-forming regions with the IRAM 30 m telescope. It was an unbiased survey in the millimeter regime, covering the prestellar core, protostar, outflow region, and protoplanetary disk phase. Here, we have reported some transitions of seven COMs, namely, methanol (CH3OH), acetaldehyde (CH3CHO), methyl formate (CH3OCHO), ethanol (C2H5OH), propynal (HCCCHO), dimethyl ether (CH3OCH3), and methyl cyanide (CH3CN) in some sources L1544, B1-b, IRAS4A, and SVS13A. We found a trend among these species from the derived abundances using the rotational diagram method and MCMC fit. We have found that the abundances of all of the COMs, except for HCCCHO, increase from the L1544 (prestellar core) and peaks at IRAS16293-2422 (class 0 phase). It is noticed that the abundance of these molecules correlate with the luminosity of the sources. The obtained trend is also visible from the previous interferometric observations and considering the beam dilution effect. Copyright © 2023, The Authors. All rights reserved.

关键词： Molecules

Study of simulations of double graded InGaN solar cell structures

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arXiv 2021年

作者： Sarollahi, Mirsaeid Aldawsari, Manal A. Allaparthi, Rohith Refaei, Malak A. Alhelais, Reem Maruf, Helal Uddin Mazur, Yuriy Ware, Morgan E. University of Arkansas Electrical Engineering Department 3217 Bell Engineering Center FayettevilleAR72701 United States University of Arkansas Microelectronics-Photonics Program 731 West Dickson Street FayettevilleAR72701 United States University of Arkansas Material Science and Engineering 731 West Dickson Street FayettevilleAR72701 United States Institute for Nanoscience and Engineering FayettevilleAR72701 United States

The performances of various configurations of InGaN solar cells are compared using nextnano software. Here we compare a flat base graded wall GaN/InGaN structure, with an InxGa1-xN well with sharp GaN contact layers, and an InxGa1-xN structure with InxGa1-xN contact layers, i.e. a homojunction. The doping in the graded structures are the result of polarization doping at each edge (10 nm from each side) due to the graded structure, while the well structures are intentionally doped at each edge (10 nm from each side) equal to the doping concentration in the graded structure. The solar cells are characterized by their open-circuit voltage, Vroc, short circuit current, Isc, solar efficiency, η, and energy band diagram. The results indicate that an increase in Isc and η results from increasing both the fixed and the maximum indium compositions, while the Vroc decreases. The maximum efficiency is obtained for the InGaN well with 60% In. © 2021, CC BY.

关键词： III-V semiconductors

Harnessing enhanced stability and high-rate capability in lithium-ion batteries using synergistic SnS 2 /MoS 2 2D nanostructures with optimized conversion/alloying reactions

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Journal of Alloys and Compounds 2024年 984卷

作者： Boya Venugopal Ravi Mudike Ranjith Ravi Prasanta Kumar Sahoo Abhishek Tripathi Indrajit Shown Institute of Atomic and Molecular Sciences Academia Sinica Taipei 10617 Taiwan Nanoscience and Technology Program Taiwan International Graduate Program Academia Sinica Taipei 11529 Taiwan Department of Engineering and System Science National Tsing Hua University Hsinchu 30013 Taiwan School of Science Minzu University of China Beijing 100081 China Department of Chemistry Hindustan Institute of Technology and Science Chennai 603103 India National Institute of Hydrology Jalvigyan Bhawan Roorkee 247667 India Department of Metallurgical and Material Engineering Malaviya National Institute of Technology Jaipur 302017 India

Recently, there has been a significant interest in the application of SnS 2 /MoS 2 2D nanostructure composites in lithium-ion batteries (LIBs) due to their advantageous conversion, intercalation, and alloying reactions, leading to high capacity during charge and discharge cycles. In this study, we successfully synthesized SnS 2 /MoS 2 composites with a 2D-nanoplate morphology using a single-step hydrothermal method. Specifically, the optimized SnS 2 /MoS 2 -3:1 composite was tested as anodes in coin cell LIBs, demonstrating an impressive capacity of 710 mAh/g at a current density of 500 mA/g, along with outstanding stability (800 cycles) and remarkable rate capability compared to other composites. The excellent electrochemical performance of the SnS 2 /MoS 2 -3:1 composite can be attributed to the moderately coupled SnS 2 and MoS 2 2D-nanosheets, which provide short lithium-ion transportation lengths, low charge transfer resistance, and dominant capacitive behavior.

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Application of recycled fibers from used aseptic carton for the production of packaging paper I - Evaluation of recyclability of used aseptic carton using pilot-scale equipments

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Palpu Chongi Gisul/Journal of Korea Technical Association of the Pulp and Paper Industry 2019年第3期51卷 5-12页

作者： Lee, Tae Joo Kim, Doo Hyun Kim, Kwang Jin Ryu, Jeong Yong Lee, Myoung Ku Chemistry Division Forest Products Department National Institute of Forest Science Seoul02455 Korea Republic of Taelim Paper Co. Ltd. Gyeonggi15609 Korea Republic of Tetrapak Korea Seoul04349 Korea Republic of Program of Paper Science and Engineering Division of Forest Material Science and Engineering College of Forest and Environmental Sciences Kangwon National University Chuncheon24341 Korea Republic of

Packaging papers are usually made of unbleached kraft pulp (UKP) and Korean old corrugated container (KOCC). The KOCC consumption for the production of kraft paper, corrugated medium, and linerboard has gradually increased with the expansion of e-commerce and parcel service industry. The most important properties of industrial papers are their strength (e.g., tensile, compression, and burst strengths) because one of their major functions is to protect goods against external forces. However, the KOCC is not enough to improve the desired strength properties because of the fiber property deterioration caused by the repeated recycling process. Therefore, a new material that would replace the KOCC in achieving an improved paper strength should be found. Aseptic carton, which comprises 80% paperboard and 20% plastic films and aluminum layers, is a potential alternative for KOCC because the paperboard in the carton pack is made of UKP. This study assessed the recyclability of used aseptic carton (UAC) using a pilot-scale pulper and a screen. The UAC yield was approximately 74%, indicating that fibers could almost be obtained via the paper recycling process. The reject materials comprised aluminum and plastics. The fiber properties were satisfactory compared to UKP. The length and width of the UAC fibers were slightly shorter and narrower and the water retention value and freeness were better than those of the other recycled fibers obtained using double lined kraft and used gable top. © 2019 Korean Technical Assoc. of the Pulp and Paper Industry. All rights reserved.

关键词： Fibers

Formation of a single quasicrystal upon collision of multiple grains

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arXiv 2021年

作者： Han, Insung Wang, Kelly L. Cadotte, Andrew T. Xi, Zhucong Parsamehr, Hadi Xiao, Xianghui Glotzer, Sharon C. Shahani, Ashwin J. Department of Materials Science and Engineering University of Michigan Ann ArborMI48109 United States Macromolecular Science and Engineering Program University of Michigan Ann ArborMI48109 United States University of Michigan Ann ArborMI48109 United States National Synchrotron Light Source-II Brookhaven National Laboratory UptonNY11973 United States Department of Chemical Engineering University of Michigan Ann ArborMI48109 United States Biointerfaces Institute University of Michigan Ann ArborMI48109 United States

Quasicrystals exhibit long-range order but lack translational symmetry. When grown as single crystals, they possess distinctive and unusual properties owing to the absence of grain boundaries. Unfortunately, conventional methods such as bulk crystal growth or thin film deposition only allow us to synthesize either polycrystalline quasicrystals or quasicrystals that are at most a few centimeters in size. Here, we reveal through real-time and 3D imaging the formation of a single decagonal quasicrystal arising from a hard collision between multiple growing quasicrystals in an Al-Co-Ni liquid. Through corresponding molecular dynamics simulations, we examine the underlying kinetics of quasicrystal coalescence and investigate the effects of initial misorientation between the growing quasicrystalline grains on the formation of grain boundaries. At small misorientation, coalescence occurs following rigid rotation that is facilitated by phasons. Our joint experimental-computational discovery paves the way toward fabrication of single, large-scale quasicrystals for novel applications. Copyright © 2021, The Authors. All rights reserved.

关键词： Quasicrystals

Bacteria-based bioactive materials for tumor immunotherapy

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Precision Medicine and Engineering

Precision Medicine and engineering 2024年第2期1卷

作者： Yongcan Li Fangfang Cao Lie Ma Lulu Jin MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 PR China Departments of Diagnostic Radiology Surgery Chemical and Biomolecular Engineering and Biomedical Engineering Yong Loo Lin School of Medicine and College of Design and Engineering National University of Singapore 119074 Singapore Nanomedicine Translational Research Program NUS Center for Nanomedicine Yong Loo Lin School of Medicine National University of Singapore 117597 Singapore

As one of the most abundant biological populations endowed with unique properties such as specific targeting and genetic engineering vectors, bacteria with immunogenic potential have garnered significant attention for their ability to elicit immune activation against tumors. This approach has achieved substantial breakthroughs as a modality for cancer treatment and is known as bacterial immunotherapy. However, the immunosuppressive tumor microenvironment (TME) can inhibit the immune response induced by bacteria and promote tumor growth and metastasis. To overcome this challenge, recent advancements in bacteria-based bioactive materials, which are biological substances synthesized by bacteria, have not only harnessed the inherent properties of bacteria but also specifically targeted the modulation of the TME, providing a more favorable environment for immune activation and significantly enhancing the efficacy of immunotherapy for cancer treatment. This review introduces the key mechanisms of bacteria-based biomaterials as anticancer agents and reviews the latest research progress, along with their clinical applications in cancer treatment. Finally, the potential and challenges of bacteria-based biomaterials for tumor therapy are explored, aiming to provide insights into the functions of bacteria-based bioactive materials and their role in advancing cancer immunotherapy while offering recommendations for the development of new bacteria-based biomaterials.

关键词： Tumor immunotherapy Immune cells Tumor microenvironment Bioactive materials