Article
Engineering, Civil
Huan Li, Kaiming Bi, Hong Hao
Summary: Recently, the tuned negative stiffness inerter damper (TNSID), which combines negative stiffness and inerter elements, has been proven effective in controlling structural vibration. This paper investigates the influence of the nonlinearity of negative stiffness on the performances of two different TNSID configurations. The study introduces the working mechanisms and optimal parameters of TNSIDs with simplified linear negative stiffness, and then analyzes the dynamic responses and unstable behaviors caused by different nonlinear negative stiffness. Parameter studies and structural optimization are also conducted to evaluate the effects and mitigate the negative impacts of the nonlinearity.
ENGINEERING STRUCTURES
(2023)
Article
Engineering, Mechanical
Kyriakos Alexandros Chondrogiannis, Vasilis Dertimanis, Boris Jeremic, Eleni Chatzi
Summary: This study develops a scheme called the NegSV device that utilizes a geometrically nonlinear mechanism to create a negative stiffness system for vibration attenuation. The device successfully alters the stiffness characteristics of the primary system and improves the overall dynamics without additional mass requirements. Experimental testing on a 3-dimensional frame structure demonstrates a reduction in acceleration and inter-storey drift response below the retrofit, while nonlinear finite element analyses show agreement with the experimental measurements and offer potential for further improvement of the mechanism's design. The proposed nonlinear device shows significant potential in attenuating structural vibration and offers ease of installation.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Geriatrics & Gerontology
Erwin Stolz, Hannes Mayerl, Wolfgang Freidl, Regina Roller-Wirnsberger, Thomas M. Gill
Summary: The study found that intrinsic capacity (IC) declines progressively in older adults and predicts negative health outcomes. Regular monitoring of IC could work as an early warning system to inform preventive efforts, reducing risks such as impaired activities of daily living, long-term nursing home stay, and mortality.
JOURNALS OF GERONTOLOGY SERIES A-BIOLOGICAL SCIENCES AND MEDICAL SCIENCES
(2022)
Article
Materials Science, Multidisciplinary
Florian Ristow, Kevin Liang, Johannes Pittrich, Jakob Scheffel, Natalie Fehn, Reinhard Kienberger, Ulrich Heiz, Aras Kartouzian, Hristo Iglev
Summary: In this study, second harmonic generation (SHG) spectroscopy was used to investigate the chiroptical properties of BINOL films with different thicknesses, incidence angles, and degrees of crystallization. The study reveals that SHG-CD measured with large beam areas can directly probe the intrinsic chirality of the sample.
JOURNAL OF MATERIALS CHEMISTRY C
(2022)
Article
Materials Science, Multidisciplinary
Insu Baek, Hyun-Woo Lee
Summary: The study reveals that the orbital Hall conductivity in group XIV elemental materials is negative and of significant magnitude, making them suitable for measuring the Orbital Hall Effect (OHE).
Article
Materials Science, Multidisciplinary
Insu Baek, Hyun-Woo Lee
Summary: The study focuses on the intrinsic orbital Hall effect (OHE) in group XIV materials such as Si, Ge, and α-Sn, revealing that their orbital Hall conductivity (OHC) is negative and significantly large, distinguishing them from other materials and suggesting their potential use in measuring OHE.
Article
Chemistry, Analytical
Rongbin Li, Hongde Xia, Qian Huang, Peter Hedstrom, Wangzhong Mu, Kai Wei, Fengqin Liu, Hongliang Zhao
Summary: Quantitative mass spectrometry analysis for multi-component gas phase reaction processes is a complex nonlinear problem with multiple inputs and outputs. Conventional linear calibration and analytical methods may lead to misjudgment of reaction mechanisms and inaccuracies in determining reaction kinetics. This study confirms the nonlinearity of mass spectrometry and proposes methods to properly handle the nonlinearity, allowing accurate determination of physical parameters and characterization of reaction mechanisms and dynamics.
ANALYTICA CHIMICA ACTA
(2022)
Article
Chemistry, Multidisciplinary
Zhanning Liu, Zhe Wang, Daofeng Sun, Xianran Xing
Summary: Calcium squarate with a rigid framework exhibits volumetric negative thermal expansion and uniaxial zero thermal expansion, originating from the transverse vibration of the bridging squarate ligand. This study provides insight into the origin of NTE and the structural flexibility of metal organic frameworks.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Michael Hoffmann, Mengcheng Gui, Stefan Slesazeck, Riccardo Fontanini, Mattia Segatto, David Esseni, Thomas Mikolajick
Summary: Utilizing ferroelectric negative capacitance in Hf0.5Zr0.5O2-based thin films shows great promise for nanoscale electronic devices. Investigating heterostructures reveals that the negative capacitance is intrinsic to the Hf0.5Zr0.5O2 layer, which is crucial for potential applications. Energy barrier for polarization switching in Hf0.5Zr0.5O2 is found to be independent of domain configuration and layer thickness, in agreement with first principles calculations.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Ying Zhao, Emma Rostal Sorensen, Thomas Toft Lindkvist, Christina Kjaer, Mogens Brondsted Nielsen, Li Chen, Steen Brondsted Nielsen
Summary: The study found that when ionic dyes are close together, the internal Coulomb interaction affects their photophysics and energy-transfer efficiency. Experimental and computational results show that the distance between the three rhodamines is too large to induce a Stark shift, and the electric field acting on each dye from the other two is too small to induce a dipole moment.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Acoustics
Jen-San Chen, Sin-Yin Chen, Wei-Zhe Hsu
Summary: The study investigates the impact of nonlinear terms arising from exact geometry on the dynamic response of the mass-beam-foundation system. It focuses on scenarios where the moving speed of the point mass exceeds the critical speed. By discretizing the partial differential equation of motion using a harmonic expansion method, the feasibility of the technique is verified. In the nonlinear system, the dynamic response eventually settles into a steady state of periodic motion as the beam behaves like a hardening spring.
JOURNAL OF SOUND AND VIBRATION
(2021)
Article
Physics, Fluids & Plasmas
Peixing Niu, Michael D. Atkins, Yanyan Liu, Moxiao Li, Tian Jian Lu, Tongbeum Kim
Summary: This article investigates the equilibrium state of a specific type of samaras through in situ measurements. It establishes a correlation between dynamic pressure and disc loading, and reveals that the terminal descent velocity and disc loading of stable autorotating samaras are inversely proportional to the coefficient of lift.
Article
Mathematics
Luigi Appolloni, Simone Secchi
Summary: This study investigates the existence of solutions to the fractional nonlinear Schrodinger equation in the Sobolev space, proving the existence of a ground state solution and a multiplicity result in the radially symmetric case.
JOURNAL OF DIFFERENTIAL EQUATIONS
(2021)
Article
Biotechnology & Applied Microbiology
Fanqiang Meng, Yanan Liu, Ting Nie, Chao Tang, Fengxia Lyu, Xiaomei Bie, Yingjian Lu, Mingwen Zhao, Zhaoxin Lu
Summary: Antibiotic resistance is a global health concern. Plantaricin A (PlnA) enhances the potency of antibiotics and slows down the development of antibiotic resistance. Among the PlnA1 analogs, OP4 demonstrates good performance in the permeability of the bacterial outer membrane, cytotoxicity, and therapeutic index. Furthermore, OP4 heightens the potency of erythromycin against Escherichia coli and relieves inflammation.
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
(2022)
Article
Engineering, Mechanical
Hao Kuang, Yi Qiu, Chi Liu, Xu Zheng
Summary: This paper presents a model that effectively characterizes the nonlinearity in the apparent mass of a seated human body subjected to vertical vibration. The model was validated through vibration measurement and sensitivity analysis, and it holds significant potential for improving seating systems and enhancing ride comfort in vehicles.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2023)
