The crucial role of counter ions on the NIR absorption properties is emphasized by replacing perchlorate (ClO 4) with bistriflimide (TFSI) anions. The …

It could be calculated that the peak absorption intensity at ~1930 nm is near e 100 times higher than the peak at ~1450 nm for every 1 cm of transmission, thus …

Abstract. In this study, we introduce a metamaterial absorber operating in the near infrared region. The current metamaterial absorber (MMA) comprising Silver-SiC-Gold demonstrates an absorptivity exceeding 80% within the wavelength range of 770 nm to 1150 nm. The current metamaterials absorber exhibits independence from both …

Two types of ultra-broadband long wavelength infrared (LWIR) absorbers with small period and super thin thickness are designed and the proposed absorber is polarization-independent and possesses a good tolerance of incident angle. Two types of ultra-broadband long wavelength infrared (LWIR) absorbers with small period and super …

Fluorophores that emit in the near-infrared (NIR, 700-1700 nm) and have high quantum yields are urgently needed for many technical applications such as organic light-emitting diodes or bioimaging.

Extended viologens give strong absorptivity, tailing absorption into near-IR region. • Highest molar absorptivity 278,000 M −1 cm −1 in methanol at peak maximum 576 nm. • Weak photoluminescence behavior …

Abstract. In this paper we present the absorption coefficient mu (a) and the isotropic scattering coefficient mu (s) (') for 22 human skin samples measured using a double integrating sphere apparatus in the wavelength range of 1000-2200 nm. These in vitro results show that values for mua) follow 70% of the absorption coefficient of water and ...

Absorptivity – Absorptance. Another important radiation property of a surface is its absorptivity, α, which is the fraction of the radiation energy incident on a surface that is absorbed by the surface. Like emissivity, value of absorptivity is in the range 0 < α < 1. From its definition, a blackbody, which is an idealized physical body ...

We study the mixing schemes or the molecular processes occurring in aqueous acetonitrile (ACN) and acetone (ACT) by near-infrared spectroscopy (NIR). Both solutions (any other aqueous solutions) are not free from strong and complex intermolecular interactions. To tackle such a many-body problem, we first use the concept of the excess molar …

The fabricated W radiation antennas yielded greater absorptivity in visible to near-infrared wavelengths by increasing the aspect ratio of the cones, resulting in a near two-fold enhancement in average absorptivity compared to a reference planar W substrate. The measured absorptivity spectra were reproduced well by electromagnetic …

We have investigated a facile design, easy-to-fabricate, wideband MM-based absorber that operates in the visible and near-infrared regimes. The wideband absorptivity is noticed from 400 to 1600 nm. We noticed that absorptivity remains above 85% for the entire operating wavelength in case of normal incidence of the excitation of …

Near-infrared (NIR) spectroscopic techniques can be utilized for the non-invasive quantification of multiple analytes in aqueous materials [1][2] [3] [4]. Due to the low absorptivity of water ...

The exceedingly fragile nature of thermally grown Au-black coating makes handling and patterning a critical issue. Infrared absorption characteristics of near atmospheric, N 2 ambient DC sputtered Au thin films are studied for this purpose. The thin Au films are sputtered at different chamber pressures in Ar and N 2 /Ar gas ambient from …

The traditional bioimaging window is usually located in the first near-infrared (NIR-I) region, which is ranging from 760 to 900 nm 40, 41. The light absorption by water substantially improves ...

This study experimentally demonstrates two types of ultra-broadband metamaterial absorbers with high performance in the visible-to-near-infrared range by using different anti-reflection coatings (i.e., SiO2 and Si3N4) and a multi-subcell Ti-SiO2-Ti metasurface. Compared to the bare metamaterial nanostructure, the absorption …

Integrated near infrared ... Absorptivity measured in this way is essentially constant across the absorption envelope and is found to be 336 L mol –1 cm –1 with a standard deviation of 4 L mol –1 cm –1 as estimated from a least squares fit of a straight line to data from water concentrations between 0.01 mol/L and 0. ...

As shown in Fig. 2 a, DB-BF4 and DB-TFSI absorbed a broad range of the near-infrared light with molar absorptivity (ε) more than 100,000 M −1 cm −1 and the molar absorptivity of DB-TFSI was higher than DB-BF4 due to the effect of counter anions on the optical properties of diimmonium dyes, which was demonstrated by our previous …

An infrared perfect absorber structure is designed based on GaAs/Au/SiO 2 metamaterial with numerical simulation, in which gold split ring resonators (SRR) …

Laser processing of polycrystalline porous graphite through micro- to millisecond pulses with 1 µm wavelength is investigated. The study aims at finding the best compromise between the efficiency of the process (ablation rate) and the quality (reduced heat-affected zone) for drilling and cutting applications. Our experimental approach is …

A novel ultra-wideband (UWB) absorber is designed and numerically analyzed to demonstrate that its light absorptivity was greater than 90% in the wavelength range of visible light and near-infrared. In this study, we designed a novel ultra-wideband (UWB) absorber and numerically analyzed it to demonstrate that its light absorptivity …

Exceptional near-infrared fluorescence quantum yields and excited-state absorptivity of highly conjugated porphyrin arrays J Am Chem Soc. 2006 Jul 19;128(28):9000-1. doi: 10.1021/ja061897o. ... Spectroscopy, Near-Infrared / methods* Substances Porphyrins ...

This study analyzes the factors that enhance the absorptivity of monolayer graphene, including the geometric parameters and the relative positions of the graphene, to provide potential application in the field of optical detection and optoelectronic devices. Monolayer graphene has poor absorption in the near-infrared region. Its layer is only as …

In this study, an absorber with the characteristics of high absorptivity and ultra-wideband (UWB), which was ranged from the visible light range and near-infrared band, was designed and numerically analyzed using COMSOL Multiphysics ® simulation software (version 6.0). The designed absorber was constructed by using two-layer square cubes …

In the past decades, spectrally selective windows, such near-infrared absorbing (NIR) glazings, low-e glazings, and various smart windows, have been widely studied, developed, and applied in different climatic conditions for building energy-saving purposes.One major pathway of the spectrally selective glazings to achieve energy …

We report a highly band-selective, bifunctional meta-surface that serves as an ultra-wide perfect absorber for near-infrared (NIR) band and a visible-band sensor, based on a rational design strategy involving stacking and/or grating of metals, inorganic insulators, and stimuli-responsive materials. PNIPAAm-based hydrogel was utilized as a …

In this work, we detail an ultrafast pump-probe transient absorption (TA) spectrometer capable of probing the near-infrared (NIR) spectral region from 900 to …

Luminescence in the near-infrared (NIR) window (700–1,700 nm), in particular, exhibits less interaction of scattering and absorption photons with biological …

Near InfraRed Spectroscopy: Absorption bands in the near infrared (NIR) region (750 - 2500 nm) are weak because they arise from vibrational overtones and combination bands. Combination bands occur when two molecular vibrations are excited …

Absorptivity measured in this way is essentially constant across the absorption envelope and is found to be 336 L mol-1 cm-1 with a standard deviation of 4 L mol-1 cm-1 as estimated from a least squares fit of a straight line to data from water concentrations between 0.01 mol/L and 0.06 mol/L. Absorptivity measured from the …

Monolayer graphene has poor absorption in the near-infrared region. Its layer is only as thick as a single atom so it cannot have a high absorptivity.

In this study, we designed a novel ultra-wideband (UWB) absorber and numerically analyzed it to demonstrate that its light absorptivity was greater than 90% in the wavelength range of visible light and near …

Integrated near infrared (NIR) absorbance has been used to determine the absorptivity of the υ2 + υ3 combination band of the asymmetric stretch (υ2) and the bending vibration (υ3) for water in ...