Color Measurements of Latices and of Rubber Films Prepared from Them

1941 ◽  
Vol 14 (4) ◽  
pp. 884-894
Author(s):  
G. Van Nederveen
Keyword(s):  
Blue Light ◽  
White Light ◽  
Visual Examination ◽  
Color Measurements ◽  
Reflected Light ◽  
Close Relationship ◽  
Lovibond Colorimeter

Abstract In the introduction to the present work, reasons for latex becoming discolored are reviewed, and the importance of color measurements are discussed. In addition, methods which have been developed for measuring the colors of various socalled white products, such as sugar, flour, paper, and the like, and methods for measuring the color of latex, are reviewed. Some of these methods are subjective; on the contrary, others utilize photocells so that subjective observations are eliminated. Measurements of the colors of different samples of latices were carried out with a Lovibond colorimeter, as a result of which it was found that this instrument is wholly unsuitable for this purpose. Measurements of the colors of both latices and films prepared from these latices were then made with a Hilger blancometer. The method of measuring and of calculating the intensity of the reflected light of a definite color is explained. The results obtained in measurements of the reflection of white light and of blue light from different samples of latex, using a Hilger blancometer, are compared with the results obtained with the same samples of latex estimated by simple visual examination. It was found that latices of good color reflect 80 or more per cent of white light and 78 or more per cent of blue light. The reflection of a yellow latex is considerably less in blue light than in white light. The reflection of a gray latex in white light does not differ much from that in blue light; in each case it is less than 80 per cent. It is proved conclusively that, judged by measurements of the colors of films, there is a close relationship between the color of a latex and the color of white-pigmented films made from the particular latex.

scholarly journals The Preferences of Different Cultivars of Lettuce Seedlings (Lactuca sativa L.) for the Spectral Composition of Light

Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1211
Author(s):  
Barbara Frąszczak ◽  
Monika Kula-Maximenko
Keyword(s):  
Chlorophyll Content ◽  
Blue Light ◽  
White Light ◽  
Leaf Shape ◽  
Red Light ◽  
Spectral Composition ◽  
Fresh Weight ◽  
Light Spectrum ◽  
Dark Green ◽  
Relative Chlorophyll Content

The spectrum of light significantly influences the growth of plants cultivated in closed systems. Five lettuce cultivars with different leaf colours were grown under white light (W, 170 μmol m−2 s−1) and under white light with the addition of red (W + R) or blue light (W + B) (230 μmol m−2 s−1). The plants were grown until they reached the seedling phase (30 days). Each cultivar reacted differently to the light spectrum applied. The red-leaved cultivar exhibited the strongest plasticity in response to the spectrum. The blue light stimulated the growth of the leaf surface in all the plants. The red light negatively influenced the length of leaves in the cultivars, but it positively affected their number in red and dark-green lettuce. It also increased the relative chlorophyll content and fresh weight gain in the cultivars containing anthocyanins. When the cultivars were grown under white light, they had longer leaves and higher value of the leaf shape index. The light-green cultivars had a greater fresh weight. Both the addition of blue and red light significantly increased the relative chlorophyll content in the dark-green cultivar. The spectrum enhanced with blue light had positive influence on most of the parameters under analysis in butter lettuce cultivars. These cultivars were also characterised by the highest absorbance of blue light.

(K0.5Na0.5)NbO3:Eu3+/Bi3+: a novel, highly efficient, red light-emitting material with superior water resistance behavior

RSC Advances ◽  
2015 ◽  
Vol 5 (6) ◽  
pp. 4707-4715 ◽  
Author(s):  
Qiwei Zhang ◽  
Haiqin Sun ◽  
Tao Kuang ◽  
Ruiguang Xing ◽  
Xihong Hao
Keyword(s):  
Blue Light ◽  
White Light ◽  
High Performance ◽  
Water Resistance ◽  
Light Emitting Diodes ◽  
Red Light ◽  
Light Emitting ◽  
Highly Efficient ◽  
White Light Emitting Diodes

Materials emitting red light (∼611 nm) under excitation with blue light (440–470 nm) are highly desired for fabricating high-performance white light-emitting diodes (LEDs).

A novel green phosphor LaMgAl11O19:Ho3+ for near-UV/blue light-pumped white light-emitting diodes

2015 ◽  
Vol 618 ◽  
pp. 182-185 ◽  
Author(s):  
Xin Min ◽  
Minghao Fang ◽  
Zhaohui Huang ◽  
Hao Liu ◽  
Yan’gai Liu ◽  
...  
Keyword(s):  
Blue Light ◽  
White Light ◽  
Light Emitting Diodes ◽  
Green Phosphor ◽  
Light Emitting ◽  
White Light Emitting Diodes

Blue-light imaging compared with high-definition white light for real-time histology prediction of colorectal polyps less than 1 centimeter: a prospective randomized study

2019 ◽  
Vol 89 (3) ◽  
pp. 554-564.e1 ◽  
Author(s):  
Emanuele Rondonotti ◽  
Silvia Paggi ◽  
Arnaldo Amato ◽  
Giuseppe Mogavero ◽  
Alida Andrealli ◽  
...  
Keyword(s):  
Real Time ◽  
Blue Light ◽  
White Light ◽  
Randomized Study ◽  
Colorectal Polyps ◽  
Prospective Randomized Study ◽  
High Definition

scholarly journals Identification and expression of the trehalose-6-phosphate synthase gene family members in tomato exposed to different light spectra

2017 ◽  
Vol 69 (1) ◽  
pp. 93-101
Author(s):  
Zexiong Chen ◽  
Juan Lou
Keyword(s):  
Plant Growth ◽  
Blue Light ◽  
White Light ◽  
Growth And Development ◽  
Light Quality ◽  
Red Light ◽  
Floral Transition ◽  
Stem Length ◽  
Pcr Analysis ◽  
Phosphate Synthase

Light is the source of energy for plants. Light wavelengths, densities and irradiation periods act as signals directing morphological and physiological characteristics during plant growth and development. To evaluate the effects of light wavelengths on tomato growth and development, Solanum lycopersicum (cv. micro-Tom) seedlings were exposed to different light-quality environments, including white light and red light supplemented with blue light (at ratios of 3:1 and 8;1, respectively). Tomatoes grown under red light supplemented with blue light displayed significantly shorter stem length, a higher number of flower buds and rate of fruit set, but an extremely late flowering compared to white-light-grown plants. To illustrate the mechanism underlying the inhibition of stem growth and floral transition mediated by red/blue light, 10 trehalose-6-phosphate synthase (TPS) genes were identified in tomato, and bioinformatics analysis was performed. qRT-PCR analysis showed that SlTPSs were expressed widely throughout plant development and SlTPS1 was expressed at extremely high levels in stems and buds. Further analysis of several flowering-associated genes and microRNAs showed that the expressions of SlTPS1, SlFT and miR172 were significantly downregulated in tomato grown under red and blue light compared with those grown under white light, whereas miR156 transcript levels were increased. A regulatory model underlying vegetative growth and floral transition regulated by light qualities is presented. Our data provide evidence that light quality strongly affects plant growth and phase transition, most likely via the TPS1-T6P signaling pathway.

Influence of blue-light polarization on light scattering in nanocrystal luminescent glass for white light-emitting-diodes

2010 ◽  
Vol 6 (3) ◽  
pp. 164-167 ◽  
Author(s):  
Hong-guo Li ◽  
Ying-tao Zhang ◽  
Ding Zhong ◽  
Suo-cheng Xu ◽  
Qin-ni Fei ◽  
...  
Keyword(s):  
Light Scattering ◽  
Blue Light ◽  
White Light ◽  
Light Emitting Diodes ◽  
Light Polarization ◽  
Light Emitting ◽  
White Light Emitting Diodes

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

2016 ◽  
Vol 63 (2) ◽  
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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