Adaptive infrared-reflecting systems inspired by cephalopods

Science ◽  
2018 ◽  
Vol 359 (6383) ◽  
pp. 1495-1500 ◽  
Author(s):  
Chengyi Xu ◽  
George T. Stiubianu ◽  
Alon A. Gorodetsky
Keyword(s):  
Protective Clothing ◽  
Fast Response ◽  
Infrared Region ◽  
Electromagnetic Spectrum ◽  
Autonomous Operation ◽  
Building Insulation ◽  
Energy Conserving ◽  
Scientific Challenge ◽  
External Stimuli ◽  
Repeated Cycling

Materials and systems that statically reflect radiation in the infrared region of the electromagnetic spectrum underpin the performance of many entrenched technologies, including building insulation, energy-conserving windows, spacecraft components, electronics shielding, container packaging, protective clothing, and camouflage platforms. The development of their adaptive variants, in which the infrared-reflecting properties dynamically change in response to external stimuli, has emerged as an important unmet scientific challenge. By drawing inspiration from cephalopod skin, we developed adaptive infrared-reflecting platforms that feature a simple actuation mechanism, low working temperature, tunable spectral range, weak angular dependence, fast response, stability to repeated cycling, amenability to patterning and multiplexing, autonomous operation, robust mechanical properties, and straightforward manufacturability. Our findings may open opportunities for infrared camouflage and other technologies that regulate infrared radiation.

scholarly journals Non-surgical treatments of complications after dental implantation. Perspectives for infrared laser light in the treatment of mucositis and peri-implantitis

2020 ◽  
Vol 24 (1) ◽  
pp. 49-56
Author(s):  
I. N. Razina ◽  
L. M. Lomiashvili ◽  
V. B. Nedoseko
Keyword(s):  
Laser Light ◽  
Antimicrobial Effect ◽  
Infrared Region ◽  
Surface Cleaning ◽  
Electromagnetic Spectrum ◽  
Implant Surface ◽  
Dental Implantation ◽  
Surgical Treatments ◽  
Further Development ◽  
Inflammatory Effect

The present article is a review of literature sources and electronic databases on the conservative treatment of mucositis and peri-implantitis. The authors analyze potentials of diode lasers, generating light in the infrared region of electromagnetic spectrum. They discuss further development of this direction and issues for the application of this type of lasers in implantology. They also discuss several parameters for the discussed laser light in dental implantology, like: antimicrobial effect, thermal effect, possible damage to implant surface, biostimulating and anti-inflammatory effect, better implant surface cleaning, accelerated osseointegration, control for apical migration and formation of stable denture attachment.

scholarly journals Hyperspectral and Multispectral Image Fusion Techniques

2020 ◽  
Vol 8 (5) ◽  
pp. 467-471
Keyword(s):  
Image Fusion ◽  
Hyperspectral Imaging ◽  
Near Infrared ◽  
Spatial Information ◽  
Hyperspectral Image ◽  
Qualitative Comparative Analysis ◽  
Infrared Region ◽  
Multispectral Image ◽  
Electromagnetic Spectrum ◽  
Fusion Methods

The hyper spectral image covers a broad range of wavelengths in electromagnetic spectrum, spanning from visible to near-infrared region. The basic objective of hyperspectral imaging is to attain the spectrum for each pixel in the image of a scene, with the aim of identifying objects in the scene and its classification. The hyperspectral images give detailed spectral information but their spatial resolution is very poor. So to enhance the visual quality of the hyperspectral image, we can perform image fusion with high spatial information multispectral image. This paper provides a complete description of hyperspectral imaging and image fusion methods of hyperspectral and multispectral images. A quantitative and qualitative comparative analysis on performance of various hyperspectral and multispectral image fusion techniques are also done.

scholarly journals Self-Propulsion of Droplets via Light-Stimuli Rapid Control of Their Surface Tension

2021 ◽  
Author(s):  
Anna Yucknovsky ◽  
Benjamin B. Rich ◽  
Ariel Westfried ◽  
Boaz Pokroy ◽  
Nadav Amdursky
Keyword(s):  
Surface Tension ◽  
Rapid Change ◽  
Fast Response ◽  
The Self ◽  
Bulk Solution ◽  
Acid Base ◽  
Ph Gradients ◽  
Light Stimuli ◽  
Chemical Wastes ◽  
External Stimuli

Biology demonstrates many examples of response and adaptation to external stimuli, and here we focus on self-propulsion (motion) while presenting several self-propelling droplet systems responsive to pH gradients. We use light as the gating source to gain reversibility, avoid the formation of chemical wastes, and control the self-propulsion remotely. To achieve light-stimuli ultra-fast response, we use photoacids and photobases, capable of donating or capturing a proton, respectively, in their excited-state. We control the movement and directionality of the droplet’s self-propulsion by introducing the photo-acid/base either in bulk solution, on the surface of the droplet, or inside the droplet. We show that proton transfer between the photo-acid/base and the droplet results in a rapid change in the droplet’s surface tension, which induces the self?propulsion movement. The high versatility of our systems together with a record-breaking ultra?fast response to light makes them highly attractive for the design of various controlled cargo?carrier systems.<br>

scholarly journals Light-Driven Crystal–Polymer Hybrid Actuators

2021 ◽  
Vol 8 ◽  
Author(s):  
Shodai Hasebe ◽  
Daisuke Matsuura ◽  
Takaaki Mizukawa ◽  
Toru Asahi ◽  
Hideko Koshima
Keyword(s):  
Single Crystal ◽  
Mechanical Performance ◽  
Molecular Crystals ◽  
Response Speed ◽  
Fast Response ◽  
Hybrid Films ◽  
Soft Robots ◽  
Responsive Materials ◽  
Wide Range ◽  
External Stimuli

Recently, soft robots, which are made of soft and light organic materials, have attracted much attention because of improved safety for daily interactions with humans. Mechanically responsive materials that can move macroscopically by external stimuli, such as light and heat, have been studied extensively over the past two decades, and they are expected to be applicable to soft robots. Among them, mechanically responsive crystals are attractive in terms of a larger Young’s modulus and faster response speed compared with polymers and gels. However, it is impractical to use one piece of a single crystal as a crystal machine; it is difficult to control the size of crystals and obtain large crystals. Hybridization of crystals with polymers is one way to create actuators with more realistic movements. Herein, we report a hybrid crystal assembly in which plate-like salicylideneaniline crystals are aligned in polymer films by a “rubbing” technique, a new approach which is inexpensive, easy, and applicable to a wide range of crystals and polymers. The hybrid films bent reversibly upon alternate irradiation with ultraviolet and visible light. The hybrid films bent as fast as single crystals, even when larger than single-crystal size, showing great mechanical performance originating from the advantages of both molecular crystals (fast response time) and polymers (large size). This work enriches the development of light-driven hybrid actuators composed of molecular crystals and polymers.

scholarly journals Validation of Spectrophotometric Methods to Determine the Concentrations of Alcohol, SO2, and Total Acids in Wine

Separations ◽  
2021 ◽  
Vol 8 (10) ◽  
pp. 191
Author(s):  
Irene Dini ◽  
Ritamaria Di Lorenzo ◽  
Antonello Senatore ◽  
Daniele Coppola ◽  
Sonia Laneri
Keyword(s):  
Infrared Region ◽  
Wine Industry ◽  
Electromagnetic Spectrum ◽  
Total Acid ◽  
Laboratory Staff ◽  
Spectrophotometric Methods ◽  
New Methods ◽  
Ft Ir ◽  
Speed Of Analysis

The determination of alcohol, SO2, and total acids in wine through conventional laboratory techniques have some limitations related to the amount of the samples, analytical preparation of laboratory staff, and time to carry out the analysis. In recent years, spectroscopic and chromatographic methods have been proposed to determinate simultaneously multiple analytical parameters. The new methods claim the speed of analysis and easy execution. However, they need a validation process that guarantees the reliability of the results to be used in official determinations. This study aimed to evaluate the usefulness of FT-infrared reflectance (FT-IR) to quantify total acid, alcohol, and SO2 concentration in the wines. For this purpose, 156 DOC Italian wines were tested with IR technology, and results were compared to those obtained by official analysis methods. The comparison was performed using two non-parametric statistical methods: the Bland & Altman test and Passing & Bablok regression. Our results showed that the spectrophotometric methods make errors due to interfering contaminants in the sample that can be corrected by blank determination. Therefore, the spectrophotometric methods that use the infrared region of the electromagnetic spectrum can be used by the wine industry and regulators for the wine routine as an alternative to official methodologies.

scholarly journals Spectral Response of Eucalyptus saligna under Water Stress in Southern Brazil

2019 ◽  
pp. 1-8
Author(s):  
Lorena de Moura Melo ◽  
Adriano Castelo Dos Santos ◽  
Kardelan Arteiro da Silva ◽  
Uilian do Nascimento Barbosa ◽  
Géssyca Fernanda De Sena Oliveira ◽  
...  
Keyword(s):  
Water Stress ◽  
Water Deficit ◽  
Near Infrared ◽  
Spectral Response ◽  
Infrared Region ◽  
Electromagnetic Spectrum ◽  
Eucalyptus Saligna ◽  
Green Vegetation ◽  
Santa Maria ◽  
Genus Eucalyptus

The present work aims to assess the effect of water stress on the reflectance emitted by leaves of Eucalyptus saligna individuals. The design was completely randomized and the study comprised 30 subjects who underwent 5 cycles of drought simulation, 45 days each. Five individuals were submitted to water deficit treatment and five were used as controls, remaining in adequate water conditions. The experiment and data collection were performed in the external facilities of the forest management laboratory of the Federal University of Santa Maria, Rio Grande do Sul, Brazil. Which it comprised the period from September 2014 to April 2015. Spectral information was collected from 24-month-old tree individuals in adequate water and water stress situations by means of FieldSpec®3 spectroradiometer. Subsequently, the spectral data for the electromagnetic spectrum range from 400 nm to 1700 nm were processed and analyzed. The resulting spectral behavior varied between water stress cycles. In the 450 nm wavelength range, the reflectances ranged from 3.8% to 7.4%, at 550 nm from 7.9% to 14% and at 650 nm from 4.8% to 8.8%. In the near infrared region, in the 900 nm to 1300 nm range, the reflectances ranged from 28% to 62%. The spectral response of E. saligna showed minimal differences when compared to healthy green vegetation, even though it was exposed to water deficit situations. From the information obtained, this research can be used as a parameter for comparative analysis between species belonging to the genus Eucalyptus sp.

scholarly journals Self-Propulsion of Droplets via Light-Stimuli Rapid Control of Their Surface Tension

2021 ◽  
Author(s):  
Anna Yucknovsky ◽  
Benjamin B. Rich ◽  
Ariel Westfried ◽  
Boaz Pokroy ◽  
Nadav Amdursky
Keyword(s):  
Surface Tension ◽  
Rapid Change ◽  
Fast Response ◽  
The Self ◽  
Bulk Solution ◽  
Acid Base ◽  
Ph Gradients ◽  
Light Stimuli ◽  
Chemical Wastes ◽  
External Stimuli

Biology demonstrates many examples of response and adaptation to external stimuli, and here we focus on self-propulsion (motion) while presenting several self-propelling droplet systems responsive to pH gradients. We use light as the gating source to gain reversibility, avoid the formation of chemical wastes, and control the self-propulsion remotely. To achieve light-stimuli ultra-fast response, we use photoacids and photobases, capable of donating or capturing a proton, respectively, in their excited-state. We control the movement and directionality of the droplet’s self-propulsion by introducing the photo-acid/base either in bulk solution, on the surface of the droplet, or inside the droplet. We show that proton transfer between the photo-acid/base and the droplet results in a rapid change in the droplet’s surface tension, which induces the self?propulsion movement. The high versatility of our systems together with a record-breaking ultra?fast response to light makes them highly attractive for the design of various controlled cargo?carrier systems.<br>

scholarly journals AVIRIS-NG Data for Geological Applications in Southeastern Parts of Aravalli Fold Belt, Rajasthan

Proceedings ◽  
2019 ◽  
Vol 24 (1) ◽  
pp. 16
Author(s):  
Sameeksha Mishra ◽  
Shovan L. Chattoraj ◽  
Alen Benny ◽  
Richa U. Sharma ◽  
P. K. Champati Ray
Keyword(s):  
High Resolution ◽  
Near Infrared ◽  
Country Rock ◽  
Satellite Image ◽  
Infrared Region ◽  
Hyperspectral Data ◽  
Electromagnetic Spectrum ◽  
Fold Belt ◽  
Spectral Angle Mapper ◽  
Iron Bearing

Advanced techniques using high resolution hyperspectral remote sensing data has recently evolved as an emerging tool with potential to aid mineral exploration. In this study, pertinently, five mosaicked scenes of Airborne Visible InfraRed Imaging Spectrometer-Next Generation (AVIRIS-NG) hyperspectral data of southeastern parts of the Aravalli Fold belt in Jahazpur area, Rajasthan, were processed. The exposed Proterozoic rocks in this area is of immense economic and scientific interest because of richness of poly-metallic mineral resources and their unique metallogenesis. Analysis of high resolution multispectral satellite image reveals that there are many prominent lineaments which acted as potential conduits of hydrothermal fluid emanation, some of which resulted in altering the country rock. This study takes cues from studying those altered minerals to enrich our knowledge base on mineralized zones. In this imaging spectroscopic study we have identified different hydrothermally altered minerals consisting of hydroxyl, carbonate and iron-bearing species. Spectral signatures (image based) of minerals such as Kaosmec, Talc, Kaolinite, Dolomite, and Montmorillonite were derived in SWIR (Short wave infrared) region while Iron bearing minerals such as Goethite and Limonite were identified in the VNIR (Visible and Near Infrared) region of electromagnetic spectrum. Validation of the target minerals was done by subsequent ground truthing and X-ray diffractogram (XRD) analysis. The altered end members were further mapped by Spectral Angle Mapper (SAM) and Adaptive Coherence Estimator (ACE) techniques to detect target minerals. Accuracy assessment was reported to be 86.82% and 77.75% for SAM and ACE respectively. This study confirms that the AVIRIS-NG hyperspectral data provides better solution for identification of endmember minerals.

scholarly journals Application of the Non-Destructive NIR Technique for the Evaluation of Strawberry Fruits Quality Parameters

Foods ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 441 ◽  
Author(s):  
Manuela Mancini ◽  
Luca Mazzoni ◽  
Francesco Gagliardi ◽  
Francesca Balducci ◽  
Daniele Duca ◽  
...  
Keyword(s):  
Near Infrared ◽  
Nir Spectroscopy ◽  
Principal Component ◽  
Infrared Region ◽  
Quality Parameters ◽  
Soluble Solids ◽  
Electromagnetic Spectrum ◽  
Least Squares Regression ◽  
Solids Content ◽  
Non Destructive

The determination of strawberry fruit quality through the traditional destructive lab techniques has some limitations related to the amplitude of the samples, the timing and the applicability along all phases of the supply chain. The aim of this study was to determine the main qualitative characteristics through traditional lab destructive techniques and Near Infrared Spectroscopy (NIR) in fruits of five strawberry genotypes. Principal Component Analysis (PCA) was applied to search for spectral differences among all the collected samples. A Partial Least Squares regression (PLS) technique was computed in order to predict the quality parameters of interest. The PLS model for the soluble solids content prediction was the best performing—in fact, it is a robust and reliable model and the validation values suggested possibilities for its use in quality applications. A suitable PLS model is also obtained for the firmness prediction—the validation values tend to worsen slightly but can still be accepted in screening applications. NIR spectroscopy represents an important alternative to destructive techniques, using the infrared region of the electromagnetic spectrum to investigate in a non-destructive way the chemical–physical properties of the samples, finding remarkable applications in the agro-food market.

scholarly journals Porous Silicon and Indium Doped Zinc Oxide Junctions: Synthesis, Characterization, and Application to Electroluminescent Devices

2017 ◽  
Vol 2017 ◽  
pp. 1-8
Author(s):  
F. Severiano ◽  
G. García ◽  
L. Castañeda ◽  
V. L. Gayou
Keyword(s):  
Zinc Oxide ◽  
Porous Silicon ◽  
Visible Region ◽  
Electrical Characterization ◽  
Precursor Solution ◽  
Infrared Region ◽  
Dip Coating ◽  
Electromagnetic Spectrum ◽  
Sem Images ◽  
Electroluminescent Devices

We report the obtaining of electroluminescent devices (ELD) from porous silicon (PS) and indium doped zinc oxide (ZnO:In) junctions. PS presented photoluminescence (PL) in the visible region of the electromagnetic spectrum. ZnO:In thin film was obtained by dip coating technique. SEM images and IR measurements showed the incorporation of the ZnO:In in the PS structure. Once obtained, the device was optically and electrically characterized. The ELD showed emission in the visible (450–850 nm) and infrared region (900–1200 nm) where it was electrically polarized. The visible emission was detected as luminescent spots on the surface. Electrical characterization was carried out by current-voltage (I-V) curves. The I-V curves showed rectifying behavior. It was related to the quenching of the EL with the process that takes place in the PS when it was immersed in the precursor solution of the ZnO:In.

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