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Search Publications by: Lei Chen (Fed)

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Displaying 1 - 25 of 76

Deep Learning Image Analysis of Nanoplasmonic Sensors: Toward Medical Breath Monitoring

November 23, 2022
Author(s)
Yangyang Zhao, Boqun Dong, Kurt D. Benkstein, Lei Chen, Kristen L. Steffens, Stephen Semancik
Sensing biomarkers in exhaled breath offers a potentially portable, cost-effective, and noninvasive strategy for disease diagnosis screening and monitoring, while high sensitivity, wide sensing range, and target specificity are critical challenges. We

Short-time dental resin biostability and kinetics of enzymatic degradation

May 9, 2018
Author(s)
Xiaohong Wang, Sheng Song, Lei Chen, Christopher M. Stafford, Jirun Sun
Resin biostability is an important concern regarding the durability of methacrylate-based dental resin restorations. Current resin biostability evaluation methods take considerable time, from weeks to months, and provide no short-time kinetics of resin

Deep Silicon Etching for X-Ray Diffraction Devices Fabrication

September 28, 2017
Author(s)
Houxun Miao, Mona Mirzaeimoghri, Lei Chen, Han Wen
We report deep reactive ion etching of silicon gratings via cryogenic and Bosch processes. An aspect ratio of > 50 is achieved for 400 nm period gratings with both processes.

Graphene microcapsule arrays for combinatorial electron microscopy and spectroscopy in liquids

April 27, 2017
Author(s)
Alexander Yulaev, Hongxuan Guo, Evgheni Strelcov, Lei Chen, Ivan Vlasssiouk, Andrei Kolmakov
An atomic-scale thickness, molecular impermeability, low atomic number, and mechanical strength make graphene an ideal electron transparent membrane for scanning electron microscopy and spectroscopy in liquids. Here, we present a novel sample platform made

Cryogenic Etching of High Aspect Ratio 400 nm Pitch Silicon Gratings

July 29, 2016
Author(s)
Houxun Miao, Lei Chen, Mona Mirzaeimoghri, Richard Kasica, Han Wen
The cryogenic process and Bosch process are two widely used processes for reactive ion etching of high aspect ratio silicon structures. This paper focuses on the cryogenic deep etching of 400.0 nm pitch silicon gratings. By creating a metal hard mask on

A universal Moire effect and application in x-Ray phase-contrast imaging

April 25, 2016
Author(s)
Houxun Miao, Alireza Panna, Andrew A. Gomella, Eric E. Bennett, sami Znati, Lei Chen, Han Wen
A moiré pattern is created by superimposing two black-and-white or gray-scale patterns of regular geometry, such as two sets of evenly spaced lines. We observed an analogous effect between two transparent phase masks in a light beam which occurs at a

Multifocus microscopy with precise color multi-phase diffractive optics applied in functional neuronal imaging

March 1, 2016
Author(s)
Sara Abrahamsson, Robert Ilic, Jan Wisniewski, Brian Mehl, Liya Yu, Lei Chen, Marcelo I. Davanco, Laura Oudjedi, Jean Bernard Fiche, Bassam Hajj, Xin Jin, Joan Pulupa, Christine Cho, Mustafa Mir, Mohamed El Beheiry, Xavier Darzacq, Marcelo Nollmann, Maxime Dahan, Carl Wu, Timothee Lionnett, James Alexander Liddle, Cornelia Bargmann
Multifocus microscopy (MFM) allows high-resolution instantaneous three-dimensional (3D) imaging and has been applied to study biological specimens ranging from single molecules inside cell nuclei to entire embryos. In any live microscopy application

Electrodeposition of gold to conformally fill high-aspect-ratio nanometric silicon grating trenches: a comparison of pulsed and direct current protocols

October 1, 2015
Author(s)
sami Znati, N Chedid, Houxun Miao, Lei Chen, Han Wen, Eric E. Bennett
Filling high-aspect-ratio trenches with gold is a frequent requirement in the fabrication of X-ray optics as well as micro-electronic components and other fabrication processes. Conformal electrodeposition of gold in sub-micron-width silicon trenches with

Rolled-Up Nanoporous Membranes by Nanoimprint Lithography and Strain Engineering

April 7, 2015
Author(s)
Jaehyun Park, ChangKyu Yoon, Qianru Jin, Lei Chen, David . Gracias
It is extremely challenging to enable nanoscale patterning in three dimensional (3D) curved geometries using conventional nanolithographic approaches. In this paper, we describe a highly parallel approach that combines nanoimprint lithography (NIL) and