scholarly journals Cascaded-Microrings Biosensors Fabricated on a Polymer Platform

Sensors ◽  
2019 ◽  
Vol 19 (1) ◽  
pp. 181 ◽  
Author(s):  
Yuxin Liang ◽  
Qi Liu ◽  
Zhenlin Wu ◽  
Geert Morthier ◽  
Mingshan Zhao
Keyword(s):  
Free Spectral Range ◽  
Volume Ratio ◽  
Cost Effective ◽  
Spectral Shift ◽  
Microring Resonators ◽  
Optical Polymer ◽  
Peak Fitting ◽  
Fitting Method ◽  
Infrared Wavelengths ◽  
Vernier Effect

Polymer-based single-microring biosensors usually have a small free spectral range (FSR) that hampers the tracing of the spectrum shifting in the measurement. A cascade of two microring resonators based on the Vernier effect, is applied in this article in order to make up for this defect. A small FSR difference between the reference microring and the sensing microring is designed, in order to superpose the periodic envelope signal onto the constituent peaks, which makes it possible to continuously track the spectrum of the sensor. The optical polymer material, Ormocore, which has a large transparent window, is used in the fabrication. The biosensor is fabricated by using an UV-based soft imprint technique, which is considered to be cost-effective and suitable for mass production. By optimizing the volume ratio of Ormocore and the maT thinner, the device can be fabricated almost without a residual layer. The device works at a wavelength of 840 nm, where water absorption loss is much lower than at the infrared wavelengths. A two-step fitting method, including single-peak fitting and whole-envelope fitting, is applied in order to trace the spectral shift accurately. Finally, the two-cascaded-microrings biosensor is characterized, and the obtained FSR is 4.6 nm, which is 16 times larger than the FSR of the single microring biosensor demonstrated in our previous work. Moreover, the sensitivity can also be amplified by 16-fold, thanks to the Vernier effect.

A new peak fitting method for 1D solid-state 29Si NMR spectra based on singular spectrum analysis

2019 ◽  
Vol 18 (01) ◽  
pp. 1941014
Author(s):  
Guiliang Li ◽  
Changjun Li ◽  
Nan Wei
Keyword(s):  
Molecular Structure ◽  
Spectrum Analysis ◽  
Nmr Spectra ◽  
Singular Spectrum Analysis ◽  
Embedding Dimension ◽  
Characteristic Peak ◽  
Gaussian Fitting ◽  
Singular Spectrum ◽  
Peak Fitting ◽  
Fitting Method

[Formula: see text]Si Nuclear Magnetic Resonance (NMR) can measure the molecular structure of silicate in oilfield reinjection water. However, noise in [Formula: see text]Si NMR spectra (NMRS) affects the determination of silicate molecular structure type. To solve this problem, a new peak fitting method (Two-step Greedy-Singular Spectrum Analysis-Gaussian Fitting Method, TSG-SSA-GFM) is proposed in this paper. This method first uses TSG to determine the embedding dimension, then uses SSA to determine the characteristic peak position. Finally, GFM is used to calculate the molar ratio of characteristic peaks. The results show that TSG can quickly determine the embedding dimension and reduce computation by at least 50% vs. the global ergodic method. The mean deviation of characteristic peak positions determined by SSA is 0.07 ppm, while Discrete Wavelet Transform (DWT) and Empirical Mode Decomposition (EMD) cannot determine characteristic peaks of [Formula: see text]Si NMRS containing overlapping peak. The average [Formula: see text]-squared of Gaussian fitting of [Formula: see text]Si NMRS is 98.4% while Lorentzian is 90.6%. Therefore, this study provides an important method for quantitative analysis of [Formula: see text]Si NMRS.

scholarly journals Picosecond optically reconfigurable filters exploiting full free spectral range tuning of single ring and Vernier effect resonators

2015 ◽  
Vol 23 (9) ◽  
pp. 12468 ◽  
Author(s):  
Roman Bruck ◽  
Ben Mills ◽  
David J. Thomson ◽  
Benedetto Troia ◽  
Vittorio M. N. Passaro ◽  
...  
Keyword(s):  
Spectral Range ◽  
Free Spectral Range ◽  
Single Ring ◽  
Vernier Effect ◽  
Reconfigurable Filters

scholarly journals III–V Nanowires: Synthesis, Property Manipulations, and Device Applications

2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
Ming Fang ◽  
Ning Han ◽  
Fengyun Wang ◽  
Zai-xing Yang ◽  
SenPo Yip ◽  
...  
Keyword(s):  
High Performance ◽  
Low Cost ◽  
Volume Ratio ◽  
Chemical Vapor ◽  
Cost Effective ◽  
Research Field ◽  
Synthesis Methods ◽  
Comprehensive Overview ◽  
Device Applications ◽  
Property Control

III–V semiconductor nanowire (NW) materials possess a combination of fascinating properties, including their tunable direct bandgap, high carrier mobility, excellent mechanical flexibility, and extraordinarily large surface-to-volume ratio, making them superior candidates for next generation electronics, photonics, and sensors, even possibly on flexible substrates. Understanding the synthesis, property manipulation, and device integration of these III–V NW materials is therefore crucial for their practical implementations. In this review, we present a comprehensive overview of the recent development in III–V NWs with the focus on their cost-effective synthesis, corresponding property control, and the relevant low-operating-power device applications. We will first introduce the synthesis methods and growth mechanisms of III–V NWs, emphasizing the low-cost solid-source chemical vapor deposition (SSCVD) technique, and then discuss the physical properties of III–V NWs with special attention on their dependences on several typical factors including the choice of catalysts, NW diameters, surface roughness, and surface decorations. After that, we present several different examples in the area of high-performance photovoltaics and low-power electronic circuit prototypes to further demonstrate the potential applications of these NW materials. Towards the end, we also make some remarks on the progress made and challenges remaining in the III–V NW research field.

scholarly journals Assessment of Thermal Maturity Trends in Devonian–Mississippian Source Rocks Using Raman Spectroscopy: Limitations of Peak-Fitting Method

2017 ◽  
Vol 5 ◽  
Author(s):  
Jason S. Lupoi ◽  
Luke P. Fritz ◽  
Thomas M. Parris ◽  
Paul C. Hackley ◽  
Logan Solotky ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Source Rocks ◽  
Thermal Maturity ◽  
Peak Fitting ◽  
Fitting Method

scholarly journals Compact Wavelength Selective Crossbar Switch with Cascaded First Order Micro-Ring Resonators

2021 ◽  
Author(s):  
Akhilesh S. P. Khope ◽  
Robert Zhang ◽  
Roger Helkey ◽  
Rod C Alferness ◽  
Adel A. M. Saleh ◽  
...  
Keyword(s):  
Spectral Range ◽  
Free Spectral Range ◽  
Ring Resonators ◽  
Microring Resonators ◽  
Worst Case ◽  
First Order ◽  
Previous Generation ◽  
Separate Control ◽  
Wavelength Selective Switch ◽  
Fabrication Variation

We demonstrate a compact 4x4 wavelength selective switch with 50 % fewer electrical pads as compared with our previous generation. We report loss and crosstalk for different paths of the switch. We measure median loss of 5.32 dB and worst case crosstalk of -35 dB. The microring resonators tune by more than one free spectral range, which is an improvement over our previous generation of switches. This switch can support 8 channels at 400 GHz spacing. We conclude that it is not possible to drive both microring resonators with the same voltage and separate control is required because of fabrication variation of the current technology.

scholarly journals Diatom Mediated Production of Fluorescent Flower Shaped Silver-Silica Nanohybrid

Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7284
Author(s):  
Piya Roychoudhury ◽  
Aleksandra Golubeva ◽  
Przemysław Dąbek ◽  
Michał Gloc ◽  
Renata Dobrucka ◽  
...  
Keyword(s):  
High Surface ◽  
Nitrate Solution ◽  
Volume Ratio ◽  
Cost Effective ◽  
Silver Nitrate Solution ◽  
Hybrid Nanoparticles ◽  
Sem Images ◽  
Light Region ◽  
Vis Spectroscopy ◽  
Sio2 Particles

Fabrication of flower-like nanostructures are gaining attention because of their high surface/volume ratio and extensive adsorption capacity. In the present investigation, flower-shaped, autofluorescent silver-silica (Ag-SiO2) hybrid nanoparticles have been fabricated exploiting diatoms as a source of nanosilica. Two different species of Gedaniella including G. flavovirens and G. mutabilis showed their efficacy in synthesizing fluorescent Ag-SiO2 nanoflowers (NFs) and nanospheres (NSs) against 9 mM silver nitrate solution, respectively. The biogenic nanoconjugate (Ag-SiO2) was characterized by Uv-vis spectroscopy, energy dispersive X-ray spectroscopy (EDS), scanning (SEM) and transmission (TEM) electron microscopy. Production of Ag-SiO2 hybrid nanoparticle was confirmed by observing both Ag and Si signals from a single nanoparticle in an EDS study. The broad and single absorption band at ~420 nm in Uv-vis spectroscopy confirmed proper miscibility and production of hybrid nanoparticles. The Ag-SiO2 nanohybrids revealed autofluorescent property under the blue light region (excitation ~450–490 nm). SEM images of particles synthesized by G. flavovirens revealed the production of microscopic flower shaped Ag-SiO2 particles with several layers of petals. A TEM study confirmed that the synthesized Ag-SiO2 NFs are variable in size with 100–500 nm in diameter. Decolorization of methylene blue after exposure to Ag-SiO2 particles confirmed catalytic activity of synthesized nanostructures. This eco-friendly method provides a new dimension in nanobiotechnology for biogenesis of such hierarchical nanostructure in a cost-effective way.

scholarly journals Automation of the Peak Fitting Method in Bone FTIR Microspectroscopy Spectrum Analysis: Human and Mice Bone Study

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Marc Gardegaront ◽  
Delphine Farlay ◽  
Olivier Peyruchaud ◽  
Hélène Follet
Keyword(s):  
Spectrum Analysis ◽  
Nondestructive Method ◽  
Automatic Process ◽  
Ftir Microspectroscopy ◽  
Analysis Process ◽  
Peak Fitting ◽  
Fitting Method ◽  
Rigorous Framework ◽  
Thin Bone ◽  
Boundary Limits

FTIR microspectroscopy (FTIRM) is a commonly used nondestructive method to characterise thin bone sections. However, spectrum analysis methods are often highly sensitive to small variations (e.g., boundary limits), thus implying a time-consuming and redundant analysis process. To solve this issue, software has been developed based on several algorithms to automate the analysis. Furthermore, a rigorous framework has been established concerning the peak fitting method to obtain the systematic best potential solution. Validation of the automatic method has been performed by comparison with the manual method. Results and validation proved the reliability of the automatic process. The developed algorithms provide the means necessary to fully compare the results between bone FTIRM studies and between different laboratories.

Adsorption potential of nanocomposites for the removal of toxins in healthcare

2020 ◽  
Vol 16 ◽  
Author(s):  
Pravin Shende ◽  
Nikita P. Devlekar
Keyword(s):  
Heavy Metals ◽  
Human Health ◽  
Industrial Wastewater ◽  
Biological Systems ◽  
High Surface ◽  
Volume Ratio ◽  
Cost Effective ◽  
Isotherm Models ◽  
Potential Applications ◽  
Enhanced Adsorption

: Industrial wastewater is one of the by-products of several industries and it consists of water that requires treatment before it is discharged in water bodies. The presence of toxins in wastewater such as dyes and heavy metals is hazardous to human health and requires effective removal to reduce environmental pollution. Industrial wastewater treatment has become a global concern in healthcare and environment leading to the development of various technologies for the removal of toxins from wastewater. Various processes and technologies such as advanced oxidation processes, adsorption and membrane technology show potential in treating industrial wastewater. Another source of toxins in the form of pesticides is harmful to human health leading to severe health problems. Nanocomposites show potential as efficient adsorbents for the removal of toxins owing to the enhanced adsorption capacity, promising physicochemical properties and high surface-to-volume ratio due to nanoscale dimension. Nanocomposites are cost effective and efficient nanoadsorbents for the removal of various toxins. This review focuses on the potential applications of nanocomposites as adsorbents for the removal of toxins like dyes, heavy metals and pesticides from wastewater and biological systems. The use of nanocomposites as efficient adsorbents in the removal of toxins, various isotherm models and adsorption kinetics applied in the mechanism of adsorption are also discussed in the article. In the near future, nanocomposites may provide a simple, economical and efficient adsorption system for the removal of toxins from wastewater and biological systems.

Sign in / Sign up

Export Citation Format

Share Document