The high red/far-red ratio supports the acclimation of fern Platycerium bifurcatum to high light

Great efforts have been made to develop color appearance models to predict color appearance of stimuli under various viewing conditions. CIECAM02, the most widely used color appearance model, and many other color appearance models were all developed based on corresponding color datasets, including LUTCHI data. Though the effect of adapting light level on color appearance, which is known as "Hunt Effect", is well known, most of the corresponding color datasets were collected within a limited range of light levels (i.e., below 700 cd/m2), which was much lower than that under daylight. A recent study investigating color preference of an artwork under various light levels from 20 to 15000 lx suggested that the existing color appearance models may not accurately characterize the color appearance of stimuli under extremely high light levels, based on the assumption that the same preference judgements were due to the same color appearance. This article reports a psychophysical study, which was designed to directly collect corresponding colors under two light levels— 100 and 3000 cd/m2 (i.e., ≈ 314 and 9420 lx). Human observers completed haploscopic color matching for four color stimuli (i.e., red, green, blue, and yellow) under the two light levels at 2700 or 6500 K. Though the Hunt Effect was supported by the results, CIECAM02 was found to have large errors under the extremely high light levels, especially when the CCT was low.

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Characteristics of Photosynthesis in Different Wheat Cultivars under High Light Intensity and High Temperature Stresses

ACTA AGRONOMICA SINICA ◽

10.3724/sp.j.1006.2008.02196 ◽

2009 ◽

Vol 34 (12) ◽

pp. 2196-2201 ◽

Cited By ~ 3

Author(s):

Xue-Li QI ◽

Lin HU ◽

Hai-Bin DONG ◽

Lei ZHANG ◽

Gen-Song WANG ◽

...

Keyword(s):

High Temperature ◽

Light Intensity ◽

High Light Intensity ◽

High Light ◽

Wheat Cultivars ◽

Temperature Stresses

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Variation in Photosynthetic Traits and Antioxidant Enzyme Activities of Wheat Seedlings Transferred from Low to High Light Growth Condition

ACTA AGRONOMICA SINICA ◽

10.3724/sp.j.1006.2010.00449 ◽

2010 ◽

Vol 36 (3) ◽

pp. 449-456 ◽

Cited By ~ 1

Author(s):

Hong-Wei LI ◽

Bin LI ◽

Qi ZHENG ◽

Zhen-Sheng LI

Keyword(s):

Antioxidant Enzyme ◽

Growth Condition ◽

Enzyme Activities ◽

High Light ◽

Antioxidant Enzyme Activities ◽

Wheat Seedlings ◽

Photosynthetic Traits

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Light Absorption and Partitioning in Response to Nitrogen in Apple Leaves

HortScience ◽

10.21273/hortsci.33.3.541a ◽

1998 ◽

Vol 33 (3) ◽

pp. 541a-541

Author(s):

Lailiang Cheng ◽

Leslie H. Fuchigami ◽

Patrick J. Breen

Keyword(s):

High Light ◽

Thermal Dissipation ◽

Photochemical Quenching ◽

Light Conditions ◽

Psii Efficiency ◽

Fluorescence Measurements ◽

Free Radical Formation ◽

Highly Correlated ◽

Non Photochemical Quenching ◽

Leaf N

Bench-grafted Fuji/M26 apple trees were fertigated with different concentrations of nitrogen by using a modified Hoagland solution for 6 weeks, resulting in a range of leaf N from 1.0 to 4.3 g·m–2. Over this range, leaf absorptance increased curvilinearly from 75% to 92.5%. Under high light conditions (1500 (mol·m–2·s–1), the amount of absorbed light in excess of that required to saturate CO2 assimilation decreased with increasing leaf N. Chlorophyll fluorescence measurements revealed that the maximum photosystem II (PSII) efficiency of dark-adapted leaves was relatively constant over the leaf N range except for a slight drop at the lower end. As leaf N increased, non-photochemical quenching under high light declined and there was a corresponding increase in the efficiency with which the absorbed photons were delivered to open PSII centers. Photochemical quenching coefficient decreased significantly at the lower end of the leaf N range. Actual PSII efficiency increased curvilinearly with increasing leaf N, and was highly correlated with light-saturated CO2 assimilation. The fraction of absorbed light potentially used for free radical formation was estimated to be about 10% regardless of the leaf N status. It was concluded that increased thermal dissipation protected leaves from photo-oxidation as leaf N declined.

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Influence of Etching Regimes on the Reflectance of Black Silicon Films Formed by Ni-Assisted Chemical Etching

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.806.24 ◽

2019 ◽

Vol 806 ◽

pp. 24-29 ◽

Cited By ~ 1

Author(s):

Olga V. Volovlikova ◽

S.A. Gavrilov ◽

P.I. Lazarenko ◽

A.V. Kukin ◽

A.A. Dudin ◽

...

Keyword(s):

Refractive Index ◽

Treatment Duration ◽

Chemical Etching ◽

Visible Region ◽

High Light ◽

Silicon Films ◽

Black Silicon ◽

Metal Assisted Chemical Etching ◽

Light Absorptance

This paper examines the influence of etching regimes on the reflectance of black silicon formed by Ni-assisted chemical etching. Black silicon exhibits properties of high light absorptance. The measured minimum values of the reflectance (R-min) of black silicon with thickness of 580 nm formed by metal-assisted chemical etching (MACE) for 60 minutes at 460 lx illumination were 2,3% in the UV region (200–400 nm), 0,5% in the visible region (400–750 nm) and 0,3% in the IR region (750–1300 nm). The findings showed that the reflectance of black silicon depends on its thickness, illumination and treatment duration. In addition, the porosity and refractive index were calculated.

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Black TiOx Films with Photothermal-Assisted Photocatalytic Activity Prepared by Reactive Sputtering

Materials ◽

10.3390/ma14102508 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2508

Author(s):

Quan Mao ◽

Meng Liu ◽

Yajie Li ◽

Yuquan Wei ◽

Yong Yang ◽

...

Keyword(s):

Photocatalytic Activity ◽

Magnetron Sputtering ◽

High Light ◽

Chemical Compositions ◽

Practical Application ◽

Dc Magnetron Sputtering ◽

Optical Absorbance ◽

Low Efficiency ◽

Tio2 Phase ◽

Photocatalytic Tio2

Titanium oxide is widely applied as a photocatalyst. However, its low efficiency and narrow light absorption range are two main disadvantages that severely impede its practical application. In this work, black TiOx films with different chemical compositions were fabricated by tuning target voltage and controlling O2 flow during reactive DC magnetron sputtering. The optimized TiOx films with mixed phases (TiO, Ti2O3, Ti3O5, and TiO2) exhibited fantastic photothermal and photocatalytic activity by combining high light-absorptive Ti2O3 and Ti3O5 phases with the photocatalytic TiO2 phase. The sample prepared with oxygen flow at 5.6 ± 0.2 sccm and target voltage near 400 V exhibited excellent optical absorbance of 89.29% under visible light, which could improve surface temperature to 114 °C under sunlight. This film could degrade Rhodamine-B up to 74% after 150 min of UV irradiation. In a word, this work provides a guideline for fabricating black TiOx films with photothermal-assisted photocatalytic activity by reactive DC magnetron sputtering, which could avoid the usage of hydrogen and is convenient for quantity preparation.

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