Article
Engineering, Manufacturing
Shuai Zhang, Shanggeng Li, Xiangyu Wan, Jiajun Ma, Ning Li, Jing Li, Qiang Yin
Summary: This study synthesized a series of photo initiators for additive manufacturing and investigated their performance and the relationship between structure and property. The experimental results showed that benzophenone-based photoinitiators have higher manufacturing speed and broader applicable processing windows, potentially improving manufacturing efficiency.
ADDITIVE MANUFACTURING
(2021)
Article
Chemistry, Physical
Hui Yang, Xiaodong Li, Xuemin Guo, Chunyan Lu, Haobo Yuan, Acan Liu, Wenxiao Zhang, Junfeng Fang
Summary: To address the issue of iodine diffusion and escape in perovskite solar cells (PSCs), a strategy of iodine confinement by incorporating poly(2-vinylpyridine) (P2VP) into the perovskite film is proposed. The P2VP effectively bonds with the iodine product to inhibit diffusion and volatilization, thus suppressing perovskite decomposition and device degradation. The resulting PSCs exhibit high efficiency and good stability.
ACS ENERGY LETTERS
(2023)
Article
Biochemical Research Methods
Aaron K. Laviolette, Dimitre G. Ouzounov, Chris Xu
Summary: Measurements of three-photon action cross-sections for fluorescein in water with pH -11.5 were conducted using a femtosecond wavelength tunable non-collinear optical parametric amplifier. The excitation wavelength range was from 1154 to 1500 nm in 50 nm steps. The results confirmed the cube-law power dependance and revealed differences in the three-photon excitation spectrum compared to the one- and two-photon excitation spectra. The observed significant difference in three-photon action cross-sections at different wavelengths suggests the presence of resonance enhancement.
BIOMEDICAL OPTICS EXPRESS
(2023)
Article
Nanoscience & Nanotechnology
Chenxi Zhang, Ganying Zeng, Renyan Zhang, Yuxiang Tang, Qirui Liu, Tian Jiang
Summary: In this study, it was demonstrated that the nonlinear absorption effect of few-layer graphene changes from saturable absorption to reverse saturable absorption after lithium intercalation, attributed to charge transfer increasing the Fermi energy. The modulation depth of RSA in lithiated graphene increases with decreasing incident laser wavelength, different from pristine graphene. Additionally, the results suggest a shift in Fermi surface energy levels in lithiated graphene, paving the way for the development of nonlinear optical devices based on 2D intercalation compounds.
Article
Chemistry, Multidisciplinary
Zheng Zheng, Hequn Zhang, Hui Cao, Junyi Gong, Mubin He, Xuexin Gou, Tianyu Yang, Peifa Wei, Jun Qian, Wang Xi, Ben Zhong Tang
Summary: This study successfully synthesized four bright fluorophores with aggregation-induced emission features, which exhibited high quantum yields. One of the fluorophores (DCBT) showed bright near-infrared emission and large three-photon absorption cross section, which was further enhanced by molecular stacking. These fluorophores were applied in three-photon fluorescence microscopy imaging of mouse brain vasculature with high spatial resolution, and even small capillaries could be identified below the skull.
Article
Chemistry, Multidisciplinary
Heng An, Detian Li, Xuan Wen, Shengsheng Yang, Chenguang Zhang, Jun Wang, Zhou Cao
Summary: The pulsed laser has become the standard method for studying the single-event effects of micro-nano devices, acting as a powerful supplement to heavy ion experiments on single-event effects. With the improvement of electronic devices, the femtosecond pulse laser has a wide range of applications and practical value in single-event effects testing and radiation hardness evaluations.
APPLIED SCIENCES-BASEL
(2022)
Article
Environmental Sciences
Johannes N. Hansen, Steven Hancock, Ludwig Prade, Gerald M. Bonner, Haochang Chen, Ian Davenport, Brynmor E. Jones, Matthew Purslow
Summary: This paper investigates the potential for using diode lasers as an alternative to solid-state lasers in satellite lidar applications. The authors assess whether the novel lidar modalities necessitated by lower peak powers of diode lasers can match the design performance of existing instruments. The results show that diode lasers have the opportunity to be used in spaceborne lidars, potentially allowing wider coverage through their higher efficiencies.
Article
Chemistry, Analytical
Zhenghui Yang, Xin Lu, Jialu Shi, Xiaolu Liu, Bo Li, Tong Zhu, Qiong Zhang, Yupeng Tian, Lijun Wu, Xiaohe Tian
Summary: Researchers designed a novel three-photon absorption photostable luminogen X1 with aggregation induced emission and multi-photon imaging capability. By using a suitable delivery vector, X1 compound can be applied as a live cell imaging probe to study lipids droplets/lysosome interaction in depth tissues.
Article
Physics, Multidisciplinary
Wenjing Cheng, Yuan Li, Hongzhen Qiao, Meng Wang, Shaoshuo Ma, Fangjie Shu, Chuanqi Xie, Guo Liang
Summary: In this paper, the resonance-mediated (1 + 2)-three-photon absorption in Pr3+ ions is theoretically studied by rectangle phase modulation. The results show that this absorption can be effectively enhanced by properly designing the phase modulation. The research provides important insights for understanding and controlling multi-photon absorption in rare-earth ions, and improving up-conversion luminescence.
Article
Optics
Georgia Konstantinou, Antoine Boniface, Damien Loterie, Eirini Kakkava, Demetri Psaltis, Christophe Moser
Summary: This study introduces an advanced digital scanning technique based on transmission matrix approach, for high-resolution three-dimensional light-based additive manufacturing. Compared to previous techniques, this method is faster, simpler, and provides smaller printing distances and smoother printed structures.
OPTICS AND LASERS IN ENGINEERING
(2023)
Article
Chemistry, Physical
Ivan D. Skurlov, Anastasiia Sokolova, Danila A. Tatarinov, Peter S. Parfenov, Danil A. Kurshanov, Azat O. Ismagilov, Aleksandra Koroleva, Denis Danilov, Evgeniy Zhizhin, Sergey Mikushev, Anton N. Tcypkin, Anatoly Fedorov, Aleksandr P. Litvin
Summary: The post-synthetic treatment of CsPbBr3 NPls with different Cd2+ sources was investigated, showing that the interplay between Cd2+ precursor, NPl concentrations, and ligands determines the kinetics of the doping process. Optimization of the treatment can boost the optical properties of NPls through doping and/or surface passivation.
Article
Chemistry, Multidisciplinary
Long Yan, Xixi Wang, Zhengce An, Zhiyong Hu, Huiming Liu, Shanhui Xu, Bo Zhou
Summary: By introducing an additional NaGdF4 layer, spatial control of energy migration among the Gd sublattice within the core-shell nanostructure can enhance the upconversion luminescence of Mn2+. This design effectively isolates the interfacial quenching interactions between the sensitized core and luminescent shell, providing an efficient channel for energy transport.
Article
Chemistry, Physical
Victor Dubois, Maxime Klausen, Frederic Castet, Jean-Baptiste Verlhac, Mireille Blanchard-Desce
Summary: A series of symmetrical conjugated dimeric coumarinyl cages was synthesized by grafting 7-diethlyamino-coumarin (DEAC) cages onto different aromatic cores with various electronic characters. These dimeric derivatives showed enhanced two-photon absorption, with the highest response obtained from the electron-withdrawing core. The nature of the core also influenced the uncaging quantum yield, with the carbazole core showing the highest yield.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2023)
Article
Physics, Multidisciplinary
Viviana Villafane, Bianca Scaparra, Manuel Rieger, Stefan Appel, Rahul Trivedi, Tongtong Zhu, John Jarman, Rachel A. Oliver, Robert A. Taylor, Jonathan J. Finley, Kai Mueller
Summary: We demonstrate efficient excitation of semiconductor quantum dots in a resonant three-photon process, while suppressing resonant two-photon excitation. Time-dependent Floquet theory is used to quantify the strength of multiphoton processes and model experimental results. The efficiency of these transitions is determined by the parity considerations in the wave functions of electrons and holes in the quantum dots. Finally, we use this technique to investigate the intrinsic properties of InGaN quantum dots, enabling direct measurement of the radiative lifetime of the lowest energy exciton states and observation of emission with a greater degree of linear polarization compared to nonresonant excitation.
PHYSICAL REVIEW LETTERS
(2023)
Article
Optics
Qianglong Li, Feng Li, Hongjun Liu, Wei Zhao, Hualong Zhao, Yishan Wang, Wenlong Wen, Xue Cao, Jinhai Si
Summary: A compact all-fiber laser source with short pulse durations and excellent performance is demonstrated using fiber quasi-rectangular pulse pre-shaping technique. The laser source is compact, robust, cost-effective, and anticipated to be widely used in industrial applications.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Engineering, Multidisciplinary
Maximilian J. Grill, Wolfgang A. Wall, Christoph Meier
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING
(2020)
Article
Engineering, Chemical
Maximilian J. Grill, Christoph Meier, Wolfgang A. Wall
Summary: This article examines the separation of two adhesive elastic fibers using numerical simulation and a finite-element model for molecular interactions. The study reveals complex system behavior and discusses the influence of different material and interaction parameters. It also highlights the importance of numerical aspects in simulating challenging computational problems.
JOURNAL OF ADHESION
(2021)
Article
Mathematics, Interdisciplinary Applications
Ivo Steinbrecher, Matthias Mayr, Maximilian J. Grill, Johannes Kremheller, Christoph Meier, Alexander Popp
COMPUTATIONAL MECHANICS
(2020)
Article
Engineering, Multidisciplinary
Christoph Meier, Sebastian L. Fuchs, A. John Hart, Wolfgang A. Wall
Summary: This paper introduces a weakly compressible smoothed particle hydrodynamics formulation for modeling the melt pool dynamics in metal additive manufacturing, with a focus on selective laser melting. The formulation considers various interface forces and proposes a novel interface stabilization scheme for stable and smooth liquid-gas interface. Multiple examples are provided to verify the accuracy and robustness of the model and method building blocks.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2021)
Article
Orthopedics
Hannes Kuttner, Emanuel Benninger, Valentin Fretz, Christoph Meier
Summary: This study compared the dose area product (DAP) and organ doses to effective doses for four standard views commonly used in pelvic surgery. Results showed a fourfold difference in effective dose between ILV and LV, and highlighted that DAP and irradiation time do not provide a reliable interpretation of the patient's radiation exposure.
EUROPEAN JOURNAL OF ORTHOPAEDIC SURGERY AND TRAUMATOLOGY
(2022)
Article
Mathematics, Interdisciplinary Applications
Ivo Steinbrecher, Alexander Popp, Christoph Meier
Summary: The article introduces a mortar-type finite element formulation for embedding curved, slender beams into 3D solid volumes, along with a consistent coupling scheme for rotational and translational constraints. It demonstrates spatial convergence behavior and avoidance of potential locking effects through numerical tests when combined with suitable solid triad definitions. The proposed formulation shows potential for investigating complex mechanical systems involving curved, slender fibers with arbitrary orientation in matrix materials.
COMPUTATIONAL MECHANICS
(2022)
Article
Emergency Medicine
Ruben A. Mazzucchelli, Tenzin Lamdark, Christoph Meier, Egil A. Brons
Summary: Surgical exploration was performed on a 69-year-old female patient with traumatic anterior dislocation of the tibialis posterior muscle tendon, leading to the successful reduction of the tendon and screw fixation of the avulsed fragment. Postoperatively, the patient showed pain-free mobility and no signs of tibial posterior muscle tendon insufficiency.
Article
Engineering, Manufacturing
Ryan W. Penny, Patrick M. Praegla, Marvin Ochsenius, Daniel Oropeza, Reimar Weissbach, Christoph Meier, Wolfgang A. Wall, A. John Hart
Summary: Uniform powder spreading is essential for producing high-quality components through powder bed additive manufacturing. Different methods, such as transmission X-ray imaging, power spectral density analysis, and multi-layer template studies, can be used to quantitatively analyze layer thickness, packing fraction, and uniformity.
ADDITIVE MANUFACTURING
(2021)
Article
Computer Science, Interdisciplinary Applications
Sebastian L. Fuchs, Patrick M. Praegla, Christian J. Cyron, Wolfgang A. Wall, Christoph Meier
Summary: This study proposes a computational modeling framework for simulating coupled microfluid-powder dynamics in additive manufacturing processes. By considering temperature-dependent surface tension and wetting effects, this framework can simulate the dynamic interactions between a liquid or gas phase and a solid phase consisting of substrate and powder particles. Several application-motivated examples demonstrate the generality and robustness of the framework.
ENGINEERING WITH COMPUTERS
(2022)
Meeting Abstract
Ophthalmology
Simon Salzmann, Christian Burri, Sami Al-Nawaiseh, Philip Wakili, Christoph Meier
INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE
(2022)
Meeting Abstract
Ophthalmology
Boris V. Stanzel, Christian Burri, Sami Al-Nawaiseh, Philip Wakili, Sylvia Jane Gasparini, Gerardo Farese, Christina Kroetz, Boris Greber, Christoph Meier, Martin Frenz, Peter Szurman, Andre Schulz, Marius Ader
INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE
(2022)
Meeting Abstract
Ophthalmology
Christian Burri, Sami Al-Nawaiseh, Andre Schulz, Philip Wakili, Gerardo Farese, Peter Szurman, Simon Salzmann, Ralf Brinkmann, Boris Povazay, Christoph Meier, Martin Frenz, Boris V. Stanzel
INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE
(2022)
Article
Mechanics
Sebastian D. Proell, Wolfgang A. Wall, Christoph Meier
Summary: This article introduces a coupled thermomechanical finite element model for the simulation of metal additive manufacturing processes at the macroscale, focusing on deriving a consistent constitutive law and utilizing dual mortar mesh tying strategies for coupling. The proposed methods are validated through elementary test cases and realistic three-dimensional examples, enhancing the understanding of basic mechanisms of residual stress generation in melting and solidification problems.
ADVANCED MODELING AND SIMULATION IN ENGINEERING SCIENCES
(2021)
Article
Mechanics
Jonas Nitzler, Christoph Meier, Kei W. Mueller, Wolfgang A. Wall, N. E. Hodge
Summary: The proposed microstructure model for Ti-6Al-4V in laser powder bed fusion processes is based on energy and mobility competitions among different species, without the need for heuristic transformation criteria. This model shows high predictive ability in predicting the spatially homogenized phase fractions of relevant microstructural species.
ADVANCED MODELING AND SIMULATION IN ENGINEERING SCIENCES
(2021)
Article
Mechanics
Sebastian L. Fuchs, Christoph Meier, Wolfgang A. Wall, Christian J. Cyron
Summary: The study proposes an approach for fluid-solid and contact interaction problems, suitable for continually changing interface topologies and dynamic phase transitions, with efficient evaluation of rigid body motion.
ADVANCED MODELING AND SIMULATION IN ENGINEERING SCIENCES
(2021)
