检索结果-内蒙古大学图书馆

Characterization of Fluorinated Polyimide Films

学校读者我要写书评

暂无评论

MRS Online Proceedings Library 2020年第1期264卷 263-268页

作者： Pradnya V. Nagarkar Jiong Ping Lu David Volfson Klavs F. Jensen Stephen D. Senturia Electronics Packaging Program and Department of Materials Science & Engineering Massachusetts Institute of Technology Cambridge Electronics Packaging Program and Department of Chemical Engineering Massachusetts Institute of Technology Cambridge Electronics Packaging Program and Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge

X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) have been used to characterize the polyimide film based on 4,4′ hexafluoro-isopropylidene -bis pthalic anhydride (HFDA) and 4,4′ -bis (4-aminophenoxy) biphenyl (APBP). Films of varying thicknesses made from diluted precursors were studied by IR and XPS. An elemental analysis and a tentative peak assignment for C 1s in XPS is presented. The HFDA-APBP thick films are stoichiometric in composition and binding energies are in good agreement with data on hexafluorodianhydride-oxydianiline (HFDA-ODA). For thinner films, certain chemical modifications were observed at high cure temperatures.

关键词：

Development of Low-Temperature Doping Process in Cdse-Nanocrystal Thin Films for Flexible Electronic and Optoelectronic Devices

学校读者我要写书评

暂无评论

SSRN

SSRN 2022年

作者： Lee, Yong Min Jung, Byung Ku Ahn, Junhyuk Park, Taesung Shin, Chanho Ng, Tse Nga Kim, In Soo Choi, Ji-Hyuk Oh, Soong Ju Department of Semiconductor Systems Engineering Korea University Seoul02841 Korea Republic of Department of Materials Science and Engineering Korea University Seoul02841 Korea Republic of Materials Science Engineering Program Department of Electrical and Computer Engineering University of California San Diego La Jolla CA92093 United States Nanophotonics Research Center Korea Institute of Science and Technology Seoul02792 Korea Republic of Department of Converging Science and Technology KHU KIST Seoul02447 Korea Republic of Resources Utilization Research Center Korea Institute of Geoscience and Mineral Resources Daejeon34132 Korea Republic of

We introduce an effective surface-doping strategy for CdSe nanocrystals (NCs) by examining the size-dependency of the doping behavior. A CdSe NC thin-film transistor (TFT) is fabricated via a doping process with InCl3 treatment followed by an annealing process. Spectroscopic and electronic device characterization reveal that smaller NCs are more effectively doped than larger NCs at all annealing temperatures. This is attributed to the larger specific surface area, where the dopant can be more readily coordinated. The degenerate behavior of a 3.3-nm CdSe-NC TFT appears at a lower temperature than that of larger NC TFTs. We achieve a high electron mobility and on-to-off current ratio of 1.79 cm2/Vs and 5.2 × 105, respectively, in a low-temperature annealing process (150 °C) with 3.3-nm CdSe NCs. This facilitates the fabrication of a flexible CdSe-NC TFT, which is demonstrated on a polyethylene terephthalate substrate with an Al2O3 dielectric layer using atomic layer deposition. The flexible 3.3-nm CdSe-NC TFT is successfully fabricated even at 150 °C, with a high on-to-off current ratio and low hysteresis at a low operation voltage, which is impossible for larger CdSe-NC TFTs. © 2022, The Authors. All rights reserved.

关键词： Nanocrystals

Empowering Biomedical Discovery with AI Agents

学校读者我要写书评

暂无评论

arXiv 2024年

作者： Gao, Shanghua Fang, Ada Huang, Yepeng Giunchiglia, Valentina Noori, Ayush Schwarz, Jonathan Richard Ektefaie, Yasha Kondic, Jovana Zitnik, Marinka Department of Biomedical Informatics Harvard Medical School BostonMA United States Department of Chemistry and Chemical Biology Harvard University CambridgeMA United States Program in Biological and Biomedical Sciences Harvard Medical School BostonMA United States Department of Brain Sciences Imperial College London London United Kingdom Harvard College CambridgeMA United States Program in Biomedical Informatics Harvard Medical School BostonMA United States Department of Electrical Engineering and Computer Science MIT CambridgeMA United States Kempner Institute for the Study of Natural and Artificial Intelligence Harvard University MA United States Broad Institute of MIT and Harvard CambridgeMA United States Harvard Data Science Initiative CambridgeMA United States

We envision "AI scientists" as systems capable of skeptical learning and reasoning that empower biomedical research through collaborative agents that integrate AI models and biomedical tools with experimental platforms. Rather than taking humans out of the discovery process, biomedical AI agents combine human creativity and expertise with AI’s ability to analyze large datasets, navigate hypothesis spaces, and execute repetitive tasks. AI agents are poised to be proficient in various tasks, planning discovery workflows and performing self-assessment to identify and mitigate gaps in their knowledge. These agents use large language models and generative models to feature structured memory for continual learning and use machine learning tools to incorporate scientific knowledge, biological principles, and theories. AI agents can impact areas ranging from virtual cell simulation, programmable control of phenotypes, and the design of cellular circuits to developing new therapies. © 2024, CC BY.

关键词： Adversarial machine learning

3D Printed Biomimetic Composite for Treatment of Osteochondral Defects: A Preliminary Study in Porcine

学校读者我要写书评

暂无评论

SSRN

SSRN 2025年

作者： Eckstein, Kevin N. Liu, Boyuan Schoonraad, Sarah A. Guastaldi, Fernando Pozzi Semeghini Uzcategui, Camila Muralidharan, Archish McLeod, Robert R. Randolph, Mark A. Bryant, Stephanie J. Ferguson, Viginia L. Paul M. Rady Department of Mechanical Engineering University of Colorado at Boulder BoulderCO80309 United States Materials Science and Engineering Program University of Colorado at Boulder BoulderCO80309 United States Division of Oral and Maxillofacial Surgery Department of Surgery Massachusetts General Hospital Harvard School of Dental Medicine Harvard Medical School BostonMA02114 United States Division of Plastic and Reconstructive Surgery Department of Surgery Massachusetts General Hospital Harvard Medical School BostonMA02114 United States Department of Electrical Computer and Energy Engineering University of Colorado at Boulder BoulderCO80309 United States Department of Chemical and Biological Engineering University of Colorado at Boulder BoulderCO80309 United States BioFrontiers Institute University of Colorado at Boulder BoulderCO80309 United States

Osteochondral defects in diarthrodial joints can occur as a result of trauma. When left untreated, the surrounding tissues experience abnormal mechanical loads that can cause further degeneration. Thus, treatment of osteochondral defects requires the ability to support physiological loads and prevent further degeneration of surrounding tissues. Additive manufacturing techniques, such as bio-ink printing, have been explored to structurally reinforce soft scaffolds;however, these methods struggle to accurately print complex designs with small feature sizes (e.g., on the order of ~100 micrometers). In this study, we present a composite osteochondral scaffold with regional stiffness gradients, optimized to mimic the mechanical properties of articular cartilage and limit high strains in the subchondral bone. This scaffold incorporates a load-bearing structure, with ≥ 180 μm diameter truss elements, that is 3D printed via projection micro-stereolithography with a biomimetic soft hydrogel. We hypothesized that incorporating a reinforcing structure with cartilage and bone regions possessing tissue-specific stiffnesses, compared to a soft gel alone, would reduce degradation of native cartilage tissue adjacent to osteochondral defects and promote multi-tissue integration in porcine knees after six weeks. Histological analysis and microcomputed tomography revealed site-specific changes in the surrounding tissue, notably in the adjacent cartilage. Mechanical evaluation of adjacent native tissue showed that scaffolds with the 3D printed composite structure resulted in 33% less surrounding cartilage degradation compared to gel-only treatments. Within the defect, the soft gel alone limited mineralization, while the composite supported mineralization but only in its stiffer region. These findings suggest that incorporating a 3D printed reinforcing osteochondral mimetic structure protects the adjacent cartilage, enhances tissue integration, and spatially supports mineralization. © 2

关键词： Bone

Observation of Colossal Terahertz Magnetoresistance and Magnetocapacitance in a Perovskite Manganite

学校读者我要写书评

暂无评论

arXiv 2023年

作者： Tay, Fuyang Chaudhary, Swati He, Jiaming Peraca, Nicolas Marquez Baydin, Andrey Fiete, Gregory A. Zhou, Jianshi Kono, Junichiro Department of Electrical and Computer Engineering Rice University HoustonTX77005 United States Applied Physics Graduate Program Smalley-Curl Institute Rice University HoustonTX77005 United States Department of Physics University of Texas at Austin AustinTX78712 United States Department of Physics Northeastern University BostonMA02115 United States Department of Physics Massachusetts Institute of Technology CambridgeMA02139 United States Materials Science and Engineering Program Mechanical Engineering University of Texas at Austin AustinTX78712 United States Department of Physics and Astronomy Rice University HoustonTX77005 United States Smalley-Curl Institute Rice University HoustonTX77005 United States Department of Materials Science and NanoEngineering Rice University HoustonTX77005 United States

We have studied the terahertz response of a bulk single crystal of La0.875Sr0.125MnO3at around its Curie temperature, observing large changes in the real and imaginary parts of the optical conductivity as a function of magnetic field. The terahertz resistance and capacitance extracted from the optical conductivity rapidly increased with increasing magnetic field and did not show any sign of saturation up to 6 T, reaching 60% and 15%, respectively, at 180 K. The observed terahertz colossal magnetoresistance and magnetocapacitance effects can be qualitatively explained by using a two-component model that assumes the coexistence of two phases with vastly different conductivities. These results demonstrate the potential use of perovskite manganites for developing efficient terahertz devices based on magnetic modulations of the amplitude and phase of terahertz waves. Copyright © 2023, The Authors. All rights reserved.

关键词： Optical conductivity

LANDMARK ALTERNATING DIFFUSION

学校读者我要写书评

暂无评论

arXiv 2024年

作者： Yeh, Sing-Yuan Wu, Hau-Tieng Talmon, Ronen Tsui, Mao-Pei Data Science Degree Program National Taiwan University Academia Sinica Taipei106 Taiwan Courant Institute of Mathematical Sciences New York University New YorkNY10012 United States Viterbi Faculty of Electrical and Computer Engineering Technion - Israel Institute of Technology Haifa3200003 Israel Department of Mathematics National Taiwan University Taipei106 Taiwan National Center for Theoretical Sciences Mathematics Division Taipei106 Taiwan

Alternating Diffusion (AD) is a commonly applied diffusion-based sensor fusion algorithm. While it has been successfully applied to various problems, its computational burden remains a limitation. Inspired by the landmark diffusion idea considered in the Robust and Scalable Embedding via Landmark Diffusion (ROSELAND), we propose a variation of AD, called Landmark AD (LAD), which captures the essence of AD while offering superior computational efficiency. We provide a series of theoretical analyses of LAD under the manifold setup and apply it to the automatic sleep stage annotation problem with two electroencephalogram channels to demonstrate its *** Codes 53Z50, 65D18 © 2024, CC BY.

关键词： Diffusion

TAROGE-M: Antarctic High-Mountain Radio Antenna Array for Detecting Ultra-High Energy ANITA Anomalous Events 38

学校读者我要写书评

暂无评论

TAROGE-M: Antarctic High-Mountain Radio Antenna Array for De...

38th International Cosmic Ray Conference, ICRC 2023

作者： Wang, Shih-Hao Chen, Pisin Chen, Yaocheng Chen, Ying-Chih Choi, Taejin Ham, Young-Bae Hsu, Shih-Ying Huang, Jian-Jung Huang, MingHuey A. Jee, Geonhwa Jung, Jongil Kim, Jieun Kuo, Chung-Yun Kwon, Hyuck-Jin Lee, Changsup Leung, Chung-Hei Liu, Tsung-Che Nam, Jiwoo Shiao, Yu-Shao J. Shin, Bok-Kyun Su, Shih-Chieh Wang, Min-Zu Wang, Shih-Hao Wang, Yu-Hsin Anker, Astrid Barwick, Steven W. Besson, Dave Z. Bouma, Sjoerd Cataldo, Maddalena Gaswint, Geoffrey Glaser, Christian Hallmann, Steffen Hanson, Jordan C. Henrichs, Jakob Kleinfelder, Stuart A. Lahmann, Robert Meyers, Zachary S. Nelles, Anna Novikov, Alexander Paul, Manuel P. Pyras, Lilly Persichilli, Christopher Plaisier, Ilse Rice-Smith, Ryan Seikh, Mohammad F. H. Tatar, Joulien Welling, Christoph Zhao, Leshan Department of Physics National Taiwan University Taipei10617 Taiwan Leung Center for Cosmology and Particle Astrophysics National Taiwan University Taipei10617 Taiwan Kavli Institute for Particle Astrophysics and Cosmology SLAC National Accelerator Laboratory Stanford University StanfordCA94305 United States Division of Atmospheric Sciences Korea Polar Research Institute Incheon Korea Republic of Department of Polar Science Korea University of Science and Technology Daejeon Korea Republic of Department of Energy Engineering National United University Miaoli Taiwan Department of Astronomy Space Science and Geology Chungnam National University Daejeon34134 Korea Republic of Department of Physics and Astronomy University of Delaware NewarkDE19716 United States Department of Electrophysics National Yang Ming Chiao Tung University Hsinchu300 Taiwan Department of applied physics National Pingtung university Pingtung900 Taiwan Chung Cheng Institute of Technology National Defense University Taoyuan335 Taiwan Undergraduate Degree Program of Systems Engineering and Technology National Yang Ming Chiao Tung University Hsinchu300 Taiwan National Nano Device Laboratories Hsinchu300 Taiwan Ulsan National Institute of Science and Technology Ulsan44919 Korea Republic of Institute of Astronomy and Astrophysics Academia Sinica Astronomy-Mathematics Building No. 1 Sec. 4 Roosevelt Rd. Taipei10617 Taiwan Department of Physics and Astronomy University of California IrvineCA92697 United States Department of Physics and Astronomy University of Kansas LawrenceKS66045 United States DESY Zeuthen15738 Germany ECAP Friedrich-Alexander-Universität Erlangen-Nürnberg Erlangen91058 Germany Uppsala University Department of Physics and Astronomy UppsalaSE-752 37 Sweden Whittier College Department of Physics WhittierCA90602 United States Department of Electrical Engineering and Computer Science University of California IrvineCA92697 United States Resea

TAROGE-M is a radio antenna array atop ∼ 2.7 km-high Mt. Melbourne in Antarctica for detecting ultra-high energy (UHE, E > 1017 eV) air showers in near-horizontal directions. Besides the detection of cosmic rays and Earth-skimming tau neutrinos, its primary goal is to reproduce the discovery and verify the origin of so-called ANITA anomalous events, having feature of upward-going UHE air showers but cannot be explained by tau neutrinos. The detection concept takes advantages of a high altitude for a broad view toward the horizon;strong and near-vertical geomagnetic field for enhancing the radio signal;and quiet radio environment in Antarctica. Its relatively simple design and high duty cycle make it easily to be extended and thus to achieve an exposure competitive with ANITA experiments within a few years. The first TAROGE-M station operating at 180-450 MHz frequencies deployed in 2020 detected seven UHE cosmic ray events within 25.3-day livetime. The events have a mean energy of ∼ 1 EeV and an estimated flux consistent with other experiments, and validate the station as an UHE particle detector. In 2022-2023 season, the system was upgraded for a robust long-term operation, with a more detailed calibration with a drone-borne pulser. We also discuss the planned upgrade, including the implementation of interferometric trigger, which is expected to increase the cosmic ray and tau neutrino acceptances by a factor of 10 at 0.1 EeV, corresponding to a lower energy threshold by a factor of 3. © Copyright owned by the author(s) under the terms of the Creative Commons.

关键词： Cosmic rays

Transverse acoustic spin and torque from pure spinning of objects

学校读者我要写书评

暂无评论

Physical Review B 2021年第6期104卷 L060104-L060104页

作者： M. Farhat P.-Y. Chen M. Amin A. Alù Y. Wu Computer Electrical and Mathematical Science and Engineering (CEMSE) Division King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia Department of Electrical and Computer Engineering University of Illinois at Chicago Chicago Illinois 60607 USA College of Engineering Taibah University Madinah 42353 Saudi Arabia Photonics Initiative Advanced Science Research Center City University of New York New York New York 10031 USA Physics Program Graduate Center City University of New York New York New York 10016 USA

Acoustic spin has been recently explored for many applications. In particular, transverse acoustic spin was demonstrated for inhomogeneous acoustic fields. In this Letter, we show the emergence of acoustic spin and torque in rotating acoustic objects of the same physical properties as the surrounding, to single out the effects purely due to rotation. The spinning of a cylindrical column of air or water in the same medium possesses intrinsic spin angular momentum, and we study the torque and force it experiences in evanescent acoustic fields. The resulting discontinuity can thus scatter sound in unusual ways, including a negative radiation force, although it has no imaginary part in its parameters.

关键词： Acoustic interactions Acoustic metamaterials Acoustic wave phenomena Linear acoustics

Unavoidable emergent biaxiality in chiral molecular-colloidal hybrid liquid crystals

学校读者我要写书评

暂无评论

arXiv 2023年

作者： Wu, Jin-Sheng Lázaro, Marina Torres Ghosh, Souvik Mundoor, Haridas Wensink, Henricus H. Smalyukh, Ivan I. Department of Physics and Chemical Physics Program University of Colorado BoulderCO United States Laboratoire de Physique des Solides UMR 8502 Université Paris-Saclay CNRS Orsay91405 France International Institute for Sustainability with Knotted Chiral Meta Matter Hiroshima University Higashihiroshima Japan Department of Electrical Computer and Energy Engineering Materials Science and Engineering Program and Soft Materials Research Center University of Colorado BoulderCO United States Renewable and Sustainable Energy Institute National Renewable Energy Laboratory University of Colorado BoulderCO80309 United States

Chiral nematic or cholesteric liquid crystals (LCs) are chiral mesophases with long-ranged orientational order featuring a quasi-layered periodicity imparted by a helical director configuration but lacking positional order. Doping molecular cholesteric LCs with thin colloidal rods with a large length-to-width ratio or disks with a large diameter-to-thickness ratio adds another level of complexity to the system because of the interplay between weak surface anchoring boundary conditions and bulk-based elastic distortions around the particle-LC interface. By using colloidal disks and rods with different geometric shapes and boundary conditions, we demonstrate that these anisotropic colloidal inclusions exhibit biaxial orientational probability distributions, where they have tendencies to orient with the long rod axes and disk normals perpendicular to the helix axis, thus imparting strong local biaxiality on the hybrid cholesteric LC structure. Unlike the situation in non-chiral hybrid molecular-colloidal LCs, where biaxial order emerges only at modest to high volume fractions of the anisotropic colloidal particles, above a uniaxial-biaxial transition concentration, the orientational probability distribution of colloidal inclusions immersed in chiral nematic hosts are unavoidably biaxial even at vanishingly low particle volume fractions. In addition, the colloidal inclusions induce local biaxiality in the molecular orientational order of the LC host medium, which enhances the weak biaxiality of the LC in a chiral nematic phase coming from the symmetry breaking caused by the presence of the helical axis. With the help of analytical modeling and computer simulations based on minimizing the Landau de Gennes free energy of the host LC around the colloidal inclusions, we explain our experimental findings and conclude that the biaxial order of chiral molecular-colloidal LCs is strongly enhanced as compared to both achiral molecular-colloidal LCs and molecular cholesteric LCs

关键词： Probability distributions