Narrow-band enhanced absorption of monolayer graphene at near-infrared (NIR) sandwiched by dual gratings

We report broadband detection of OH in a premixed CH4/air flat flame at atmospheric pressure using cavity-enhanced absorption spectroscopy based on an Er:fiber femtosecond laserand a Fourier transform spectrometer.By taking ratios of spectra measured at different heights above the burner we separate twenty OH transitions from the largely overlapping water background. Weretrieve from fits to the OH lines the relative variation of the OH concentration and flame temperature with height above the burner and compare them with 1-D simulations of the flamestructure. Full Text: PDF ReferencesG. Meijer, M. G. Boogaarts, R. T. Jongma, D. H. Parker and A. M. Wodtke, "Coherent cavity ring down spectroscopy", Chem. Phys. Lett. 217, 1, 112 (1994). CrossRef S. Cheskis, I. Derzy, V. A. Lozovsky, A. Kachanov and D. Romanini, "Cavity ring-down spectroscopy of OH radicals in low pressure flame", Appl. Phys. B 66, 3, 377 (1998). CrossRef X. Mercier, E. Therssen, J. F. Pauwels and P. Desgroux, "Cavity ring-down measurements of OH radical in atmospheric premixed and diffusion flames.: A comparison with laser-induced fluorescence and direct laser absorption", Chem. Phys. Lett. 299, 1, 75 (1999). CrossRef J. Scherer, D. Voelkel and D. Rakestraw, "Infrared cavity ringdown laser absorption spectroscopy (IR-CRLAS) in low pressure flames", Appl. Phys. B 64, 6, 699 (1997). CrossRef R. Peeters, G. Berden and G. Meijer, "Near-infrared cavity enhanced absorption spectroscopy of hot water and OH in an oven and in flames", Appl. Phys. B 73, 1, 65 (2001). CrossRef T. Aizawa, "Diode-laser wavelength-modulation absorption spectroscopy for quantitative in situ measurements of temperature and OH radical concentration in combustion gases", Appl. Opt. 40, 27, 4894 (2001). CrossRef B. Löhden, S. Kuznetsova, K. Sengstock, V. M. Baev, et al., "Fiber laser intracavity absorption spectroscopy for in situ multicomponent gas analysis in the atmosphere and combustion environments", Appl. Phys. B 102, 2, 331 (2011). CrossRef A. Matynia, M. Idir, J. Molet, C. Roche, et al., "Absolute OH concentration profiles measurements in high pressure counterflow flames by coupling LIF, PLIF, and absorption techniques", Appl. Phys. B 108, 2, 393 (2012). CrossRef R. S. Watt, T. Laurila, C. F. Kaminski and J. Hult, "Cavity Enhanced Spectroscopy of High-Temperature H2O in the Near-Infrared Using a Supercontinuum Light Source", Appl. Spectrosc. 63, 12, 1389 (2009). CrossRef C. Abd Alrahman, A. Khodabakhsh, F. M. Schmidt, Z. Qu and A. Foltynowicz, "Cavity-enhanced optical frequency comb spectroscopy of high-temperature H2O in a flame", Opt. Express 22, 11, 13889 (2014). CrossRef A. Foltynowicz, P. Maslowski, A. J. Fleisher, B. J. Bjork and J. Ye, "Cavity-enhanced optical frequency comb spectroscopy in the mid-infrared application to trace detection of hydrogen peroxide", Appl. Phys. B 110, 2, 163 (2013). CrossRef Z. Qu, R. Ghorbani, D. Valiev and F. M. Schmidt, "Calibration-free scanned wavelength modulation spectroscopy ? application to H2O and temperature sensing in flames", Opt. Express 23, 12, 16492 (2015). CrossRef L. Rutkowski, A. Khodabakhsh, A. C. Johansson, D. M. Valiev, et al., "Measurement of H2O and OH in a Flame by Optical Frequency Comb Spectroscopy", CLEO: Science and Innovations SW4H.8 (2016). CrossRef L. S. Rothman, I. E. Gordon, Y. Babikov, A. Barbe, et al., "The HITRAN2012 molecular spectroscopic database", J. Quant. Spectrosc. Radiat. Transf. 130, 4 (2013). CrossRef

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Enhanced absorption of monolayer graphene using a metal–dielectric elliptical cavity array

Optics Communications ◽

10.1016/j.optcom.2020.126075 ◽

2020 ◽

Vol 474 ◽

pp. 126075

Author(s):

Boyu Chen ◽

Guohua Hu ◽

Lei Huang ◽

Ruohu Zhang ◽

Binfeng Yun ◽

...

Keyword(s):

Monolayer Graphene ◽

Enhanced Absorption ◽

Elliptical Cavity ◽

Cavity Array

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A Study of GaAs1–xSbx Axial Nanowires Grown on Monolayer Graphene by Ga-Assisted Molecular Beam Epitaxy for Flexible Near-Infrared Photodetectors

ACS Applied Nano Materials ◽

10.1021/acsanm.9b00893 ◽

2019 ◽

Vol 2 (7) ◽

pp. 4528-4537 ◽

Cited By ~ 5

Author(s):

Surya Nalamati ◽

Manish Sharma ◽

Prithviraj Deshmukh ◽

Jeffrey Kronz ◽

Robert Lavelle ◽

...

Keyword(s):

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Near Infrared ◽

Monolayer Graphene ◽

Infrared Photodetectors

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Narrow-Band Photometry of Red Variables in Globular Clusters

International Astronomical Union Colloquium ◽

10.1017/s0252921100033480 ◽

1973 ◽

Vol 21 ◽

pp. 164-177

Author(s):

Robert F. Wing

Keyword(s):

Radial Velocity ◽

Globular Clusters ◽

Near Infrared ◽

Narrow Band ◽

Small Range ◽

Mira Variables ◽

Color System ◽

Red Giant ◽

M Stars

AbstractFourteen red variables in the southern globular clusters 47 Tuc, ω Cen, and NGC 362 have been observed on an eight-color system of narrow-band photometry in the near infrared. Temperatures are derived from blackbody fits to the calibrated fluxes, and spectral types are given for the M stars. The types observed for the three Mira variables in 47 Tuc range from M3.1 to M7.5; two small-range variables in the same cluster are later than M4. The variables in ω Cen are mostly earlier than K5, but spectra of types M3 and MO were also encountered among radial-velocity members. In both the metal-rich 47 Tuc and the metal-poor ω Cen, the relation between TiO band strength and temperature is approximately normal. Several of these stars fall well above or below the red giant branches of their clusters in diagrams of infrared magnitude against temperature. Comparisons are made with recent results obtained at Radcliffe Observatory on some of the same stars.

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MXene Ti3C2Tx for phase change composite with superior photothermal storage capability

Journal of Materials Chemistry A ◽

10.1039/c9ta03962g ◽

2019 ◽

Vol 7 (23) ◽

pp. 14319-14327 ◽

Cited By ~ 41

Author(s):

Xiaoqiao Fan ◽

Lu Liu ◽

Xin Jin ◽

Wentao Wang ◽

Shufen Zhang ◽

...

Keyword(s):

Phase Change ◽

Near Infrared ◽

Infrared Region ◽

Storage Efficiency ◽

Sunlight Irradiation ◽

Photothermal Conversion ◽

Enhanced Absorption ◽

Near Infrared Region ◽

And Storage

A novel composite PCM was facilely synthesized, which exhibited enhanced absorption peaks at visible and near-infrared region, and the photothermal conversion and storage efficiency was outstanding under simulated and actual sunlight irradiation.

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Polypeptide-Based Gold Nanoshells for Photothermal Therapy

SLAS TECHNOLOGY Translating Life Sciences Innovation ◽

10.1177/2211068216645292 ◽

2016 ◽

Vol 22 (1) ◽

pp. 18-25 ◽

Cited By ~ 3

Author(s):

Kristine M. Mayle ◽

Kathryn R. Dern ◽

Vincent K. Wong ◽

Shijun Sung ◽

Ke Ding ◽

...

Keyword(s):

Heat Generation ◽

Photothermal Therapy ◽

Near Infrared ◽

Gold Nanoshells ◽

Core Material ◽

Infrared Light ◽

Great Promise ◽

Laser Exposure ◽

Enhanced Absorption ◽

Block Copolypeptide

Targeted killing of cancer cells by engineered nanoparticles holds great promise for noninvasive photothermal therapy applications. We present the design and generation of a novel class of gold nanoshells with cores composed of self-assembled block copolypeptide vesicles with photothermal properties. Specifically, poly(L-lysine)60- block-poly(L-leucine)20 (K60L20) block copolypeptide vesicles coated with a thin layer of gold demonstrate enhanced absorption of light due to surface plasmon resonance (SPR) in the near-infrared range. We show that the polypeptide-based K60L20 gold nanoshells have low toxicity in the absence of laser exposure, significant heat generation upon exposure to near-infrared light, and, as a result, localized cytotoxicity within the region of laser irradiation in vitro. To gain a better understanding of our gold nanoshells in the context of photothermal therapy, we developed a comprehensive mathematical model for heat transfer and experimentally validated this model by predicting the temperature as a function of time and position in our experimental setup. This model can be used to predict which parameters of our gold nanoshells can be manipulated to improve heat generation for tumor destruction. To our knowledge, our results represent the first ever use of block copolypeptide vesicles as the core material of gold nanoshells.

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