Two Functional Nanofibers of Polyaniline with Application in Supercapacitor and Photosensor

A series of nanosheets and nanofibers polyaniline was prepared via controlled polymerization. The optimum acid doping amount of polyaniline was obtained (acetic acid:aniline = 7:9; hydrochloric acid:aniline = 2.5:5; citric acid:aniline = 3:5), in which the specific capacitance can reach 162.5 F/g, 271.25 F/g, 240.99 F/g, respectively. The C–V curve indicating the nanorods polyaniline photosensitive sensor chip exhibits excellent sensitivity to green light and blue light. The photocurrent of the sample doped with hydrochloric acid is closest to the 10–6 A. It can be concluded that the PANI has an immense potential in photosensitive sensors and supercapacitors.

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Blue as an Underrated Alternative to Green: Photoplethysmographic Heartbeat Intervals Estimation under Two Temperature Conditions

Sensors ◽

10.3390/s21124241 ◽

2021 ◽

Vol 21 (12) ◽

pp. 4241

Author(s):

Evgeniia Shchelkanova ◽

Liia Shchapova ◽

Alexander Shchelkanov ◽

Tomohiro Shibata

Keyword(s):

Blue Light ◽

Characteristic Point ◽

Biological Effects ◽

Green Light ◽

Estimation Accuracy ◽

Lower Sensitivity ◽

Light Spectrum ◽

Cardiovascular Parameter ◽

Temperature Conditions ◽

Characteristic Points

Since photoplethysmography (PPG) sensors are usually placed on open skin areas, temperature interference can be an issue. Currently, green light is the most widely used in the reflectance PPG for its relatively low artifact susceptibility. However, it has been known that hemoglobin absorption peaks at the blue part of the spectrum. Despite this fact, blue light has received little attention in the PPG field. Blue wavelengths are commonly used in phototherapy. Combining blue light-based treatments with simultaneous blue PPG acquisition could be potentially used in patients monitoring and studying the biological effects of light. Previous studies examining the PPG in blue light compared to other wavelengths employed photodetectors with inherently lower sensitivity to blue, thereby biasing the results. The present study assessed the accuracy of heartbeat intervals (HBIs) estimation from blue and green PPG signals, acquired under baseline and cold temperature conditions. Our PPG system is based on TCS3472 Color Sensor with equal sensitivity to both parts of the light spectrum to ensure unbiased comparison. The accuracy of the HBIs estimates, calculated with five characteristic points (PPG systolic peak, maximum of the first PPG derivative, maximum of the second PPG derivative, minimum of the second PPG derivative, and intersecting tangents) on both PPG signal types, was evaluated based on the electrocardiographic values. The statistical analyses demonstrated that in all cases, the HBIs estimation accuracy of blue PPG was nearly equivalent to the G PPG irrespective of the characteristic point and measurement condition. Therefore, blue PPG can be used for cardiovascular parameter acquisition. This paper is an extension of work originally presented at the 42nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

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Green-blue light-emitting platinum(ii) complexes of cyclometallated 4,6-difluoro-1,3-dipyridylbenzenes showing mesophase organisation

Journal of Materials Chemistry C ◽

10.1039/c5tc02077h ◽

2015 ◽

Vol 3 (39) ◽

pp. 10177-10187 ◽

Cited By ~ 12

Author(s):

Valery N. Kozhevnikov ◽

Bertrand Donnio ◽

Benoît Heinrich ◽

J. A. Gareth Williams ◽

Duncan W. Bruce

Keyword(s):

Blue Light ◽

Green Light ◽

Light Emitting

Blue-green light-emitting phosphorescent PtII complexes of 1,3-bis(2-pyridyl)benzene are reported that incorporate hexadecyl-containing fragments in the 5-position of the pyridine rings.

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Operando direct observation of spin-states and charge-trappings of blue light-emitting-diode materials in thin-film devices

Scientific Reports ◽

10.1038/s41598-020-75668-4 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Fumiya Osawa ◽

Kazuhiro Marumoto

Keyword(s):

Blue Light ◽

High Performance ◽

Density Functional ◽

Light Emitting Diode ◽

Green Light ◽

Spin States ◽

Light Emitting ◽

Full Color ◽

Color Displays ◽

Materials Used

Abstract Spin-states and charge-trappings in blue organic light-emitting diodes (OLEDs) are important issues for developing high-device-performance application such as full-color displays and white illumination. However, they have not yet been completely clarified because of the lack of a study from a microscopic viewpoint. Here, we report operando electron spin resonance (ESR) spectroscopy to investigate the spin-states and charge-trappings in organic semiconductor materials used for blue OLEDs such as a blue light-emitting material 1-bis(2-naphthyl)anthracene (ADN) using metal–insulator–semiconductor (MIS) diodes, hole or electron only devices, and blue OLEDs from the microscopic viewpoint. We have clarified spin-states of electrically accumulated holes and electrons and their charge-trappings in the MIS diodes at the molecular level by directly observing their electrically-induced ESR signals; the spin-states are well reproduced by density functional theory. In contrast to a green light-emitting material, the ADN radical anions largely accumulate in the film, which will cause the large degradation of the molecule and devices. The result will give deeper understanding of blue OLEDs and be useful for developing high-performance and durable devices.

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Blue and green are frequently seen: responses of seeds to short- and mid-wavelength light

Seed Science Research ◽

10.1017/s0960258511000444 ◽

2011 ◽

Vol 22 (1) ◽

pp. 27-35 ◽

Cited By ~ 9

Author(s):

Danica E. Goggin ◽

Kathryn J. Steadman

Keyword(s):

Blue Light ◽

Seedling Establishment ◽

Native Species ◽

Green Light ◽

Model System ◽

Light Perception ◽

Vegetative Tissues ◽

Wavelength Light

AbstractSeeds have long been a model system for studying the intricacies of phytochrome-mediated light perception and signalling. However, very little is known about how they perceive blue and green light. Cryptochromes and phototropins, the major blue-light receptors in plants, are increasingly well-studied in vegetative tissues, but their role in light perception in seeds largely remains a mystery. Green light elicits a number of responses in plants that cannot be explained by the action of any of the known photoreceptors, and some seeds are apparently also capable of perceiving green light. Here, the responses of seeds to blue and green light are collated from a thorough examination of the literature and considered from the perspective of the potential photoreceptor(s) mediating them. Knowledge of how seeds perceive wavelengths that are suboptimal for phytochrome activation could help to improve germination and seedling establishment for both crop and native species.

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Photosynthetic Physiology of Blue, Green, and Red Light: Light Intensity Effects and Underlying Mechanisms

Frontiers in Plant Science ◽

10.3389/fpls.2021.619987 ◽

2021 ◽

Vol 12 ◽

Author(s):

Jun Liu ◽

Marc W. van Iersel

Keyword(s):

Blue Light ◽

Interactive Effect ◽

Red Light ◽

Green Light ◽

Photosynthetic Photon Flux Density ◽

Interactive Effects ◽

Photon Flux ◽

Photon Flux Density ◽

Light Spectrum ◽

Response Curves

Red and blue light are traditionally believed to have a higher quantum yield of CO2 assimilation (QY, moles of CO2 assimilated per mole of photons) than green light, because green light is absorbed less efficiently. However, because of its lower absorptance, green light can penetrate deeper and excite chlorophyll deeper in leaves. We hypothesized that, at high photosynthetic photon flux density (PPFD), green light may achieve higher QY and net CO2 assimilation rate (An) than red or blue light, because of its more uniform absorption throughtout leaves. To test the interactive effects of PPFD and light spectrum on photosynthesis, we measured leaf An of “Green Tower” lettuce (Lactuca sativa) under red, blue, and green light, and combinations of those at PPFDs from 30 to 1,300 μmol⋅m–2⋅s–1. The electron transport rates (J) and the maximum Rubisco carboxylation rate (Vc,max) at low (200 μmol⋅m–2⋅s–1) and high PPFD (1,000 μmol⋅m–2⋅s–1) were estimated from photosynthetic CO2 response curves. Both QYm,inc (maximum QY on incident PPFD basis) and J at low PPFD were higher under red light than under blue and green light. Factoring in light absorption, QYm,abs (the maximum QY on absorbed PPFD basis) under green and red light were both higher than under blue light, indicating that the low QYm,inc under green light was due to lower absorptance, while absorbed blue photons were used inherently least efficiently. At high PPFD, the QYinc [gross CO2 assimilation (Ag)/incident PPFD] and J under red and green light were similar, and higher than under blue light, confirming our hypothesis. Vc,max may not limit photosynthesis at a PPFD of 200 μmol m–2 s–1 and was largely unaffected by light spectrum at 1,000 μmol⋅m–2⋅s–1. Ag and J under different spectra were positively correlated, suggesting that the interactive effect between light spectrum and PPFD on photosynthesis was due to effects on J. No interaction between the three colors of light was detected. In summary, at low PPFD, green light had the lowest photosynthetic efficiency because of its low absorptance. Contrary, at high PPFD, QYinc under green light was among the highest, likely resulting from more uniform distribution of green light in leaves.

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Effect of different wavelengths of light on laccase, cellobiose dehydrogenase, and proteases produced by Cerrena unicolor, Pycnoporus sanguineus and Phlebia lindtneri.

Acta Biochimica Polonica ◽

10.18388/abp.2015_1235 ◽

2016 ◽

Vol 63 (2) ◽

Cited By ~ 7

Author(s):

Grzegorz Janusz ◽

Justyna Sulej ◽

Magdalena Jaszek ◽

Monika Osińska-Jaroszuk

Keyword(s):

Blue Light ◽

White Light ◽

Green Light ◽

White Rot Fungi ◽

Cellobiose Dehydrogenase ◽

White Rot ◽

Pycnoporus Sanguineus ◽

Lighting Conditions ◽

Cerrena Unicolor ◽

The Media

Three species of white rot fungi: Cerrena unicolor, Phlebia lindtneri and Pycnoporus sanguineus were cultured in two different media under five different lighting conditions: dark, white, red, blue, and green light. Laccase, cellobiose dehydrogenase, and protease activities were examined in the samples. Blue light efficiently boosted laccase synthesis in C. unicolor and P. sanguineus, whereas the highest activities (20 654 nkat/l) of P. lindtneri laccase were observed when this fungus was maintained in green light. On the contrary, the green light allowed obtaining the highest activities of cellobiose dehydrogenase of C. unicolor and P. lindtneri, while CDH of P. sanguineus seems to be dependent on white light. It is clearly visible that differences in protease activities are noticeable not only between the lights variants but also among the media used. However, high proteases activities are correlated with light variants inducing laccase in Lindeberg and Holm medium. Contrary to the cellulose-based medium, where they are weak in light variants that lead to high CDH activities.

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Interplay between differentially expressed enzymes contributes to light color acclimation in marineSynechococcus

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1810491116 ◽

2019 ◽

Vol 116 (13) ◽

pp. 6457-6462 ◽

Cited By ~ 9

Author(s):

Joseph E. Sanfilippo ◽

Adam A. Nguyen ◽

Laurence Garczarek ◽

Jonathan A. Karty ◽

Suman Pokhrel ◽

...

Keyword(s):

Blue Light ◽

Light Harvesting ◽

Green Light ◽

Cysteine Residue ◽

Covalent Attachment ◽

Critical Feature ◽

Light Harvesting Complexes ◽

Important Group ◽

Chromatic Acclimation ◽

Light Color

MarineSynechococcus, a globally important group of cyanobacteria, thrives in various light niches in part due to its varied photosynthetic light-harvesting pigments. ManySynechococcusstrains use a process known as chromatic acclimation to optimize the ratio of two chromophores, green-light–absorbing phycoerythrobilin (PEB) and blue-light–absorbing phycourobilin (PUB), within their light-harvesting complexes. A full mechanistic understanding of howSynechococcuscells tune their PEB to PUB ratio during chromatic acclimation has not yet been obtained. Here, we show that interplay between two enzymes named MpeY and MpeZ controls differential PEB and PUB covalent attachment to the same cysteine residue. MpeY attaches PEB to the light-harvesting protein MpeA in green light, while MpeZ attaches PUB to MpeA in blue light. We demonstrate that the ratio ofmpeYtompeZmRNA determines if PEB or PUB is attached. Additionally, strains encoding only MpeY or MpeZ do not acclimate. Examination of strains ofSynechococcusisolated from across the globe indicates that the interplay between MpeY and MpeZ uncovered here is a critical feature of chromatic acclimation for marineSynechococcusworldwide.

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Photoreversible interconversion of a phytochrome photosensory module in the crystalline state

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1912041116 ◽

2019 ◽

Vol 117 (1) ◽

pp. 300-307 ◽

Cited By ~ 4

Author(s):

E. Sethe Burgie ◽

Jonathan A. Clinger ◽

Mitchell D. Miller ◽

Aaron S. Brewster ◽

Pierre Aller ◽

...

Keyword(s):

Single Crystal ◽

Blue Light ◽

Green Light ◽

Crystallographic Structure ◽

X Ray Diffraction ◽

Major Barrier ◽

X Ray ◽

Spectroscopic Analyses ◽

Serial Femtosecond Crystallography

A major barrier to defining the structural intermediates that arise during the reversible photointerconversion of phytochromes between their biologically inactive and active states has been the lack of crystals that faithfully undergo this transition within the crystal lattice. Here, we describe a crystalline form of the cyclic GMP phosphodiesterases/adenylyl cyclase/FhlA (GAF) domain from the cyanobacteriochrome PixJ inThermosynechococcus elongatusassembled with phycocyanobilin that permits reversible photoconversion between the blue light-absorbing Pb and green light-absorbing Pg states, as well as thermal reversion of Pg back to Pb. The X-ray crystallographic structure of Pb matches previous models, including autocatalytic conversion of phycocyanobilin to phycoviolobilin upon binding and its tandem thioether linkage to the GAF domain. Cryocrystallography at 150 K, which compared diffraction data from a single crystal as Pb or after irradiation with blue light, detected photoconversion product(s) based on Fobs− Fobsdifference maps that were consistent with rotation of the bonds connecting pyrrole rings C and D. Further spectroscopic analyses showed that phycoviolobilin is susceptible to X-ray radiation damage, especially as Pg, during single-crystal X-ray diffraction analyses, which could complicate fine mapping of the various intermediate states. Fortunately, we found that PixJ crystals are amenable to serial femtosecond crystallography (SFX) analyses using X-ray free-electron lasers (XFELs). As proof of principle, we solved by room temperature SFX the GAF domain structure of Pb to 1.55-Å resolution, which was strongly congruent with synchrotron-based models. Analysis of these crystals by SFX should now enable structural characterization of the early events that drive phytochrome photoconversion.

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