StilbeneC₁₄H₁₂

Miyazaki Kita Senior High School
Ono Mai
Taketsugu syuto
Uchida Aya
Kawakami Hiroto

Stilbene Luminous

What is brightening

Exchange the trans type and cis type with ultraviolet energy

Whiten cloth or paper and fluoresce blue –violet when exposed to ultraviolet rays.
Since it looks white to the human eye. They
can make cloth or paper look white
They can also remove the yellowing.

Trans type

Hypothesis

cis type

Absorptiometry
The concentration of the substance is quantitatively analyzed by irradiating thesolution with light and measuring the absorbance when thelight reflects the reagent.

Ｌａｍｂｅｒｔ-Beer’s law
The law that the absorbance of a substance at a specific wavelength is
proportional to the concentration of the substance and the thickness of theabsorption layer.
Abs=ɛcl(Absorbance = molar extinction coefficient x concentration x optical path length)①Grind stilbene.
②Stilbene melt in benzene.
It’s because stilbene doesn’t melt inwater.
③Cloth put on the solution and mix untilpenetrate.
④Wash away in water at 3 times.
⑤hit UV light inside the cardboard so that itis not exposed to light from the outside .
⑥Take picture of the cloth and analysis withImegeJ.
Constant conditions④Water is 300ml and wash 3minutes a once

Experimental Result➀

We find when hit UV at stilbene ,stilbene absorb
and out blue light .since the amount of stilbene is
not written on the detergent I wanted to know theamount contained.

Experiment method②

Experiment method①① The higher the amount of stilbene
Absorb ultraviolet rays.
②the more stilbene a liquid contains , the more light it absorbs and higher abs,
greater the amount of detergent contained in that detergent .

Motivation① Grind stilbene.
② Dissolve stilbene with the minimum amount of benzene.
③ Put the solution of ② into a volumetric flask and dilutewith benzene.
④ Put only benzene into the cell and base correct with aspectrophotometer*Because benzene also absorbs ultraviolet rays
⑤ Put the solution of ② into the cell.
⑥ Measure with a spectrophotometer.
⑦ Make a graph by combining the numerical values.
⑧ Dissolve the detergent in benzene and measure with aspectrophotometer.
⑨ Find the amount of stilbene contained in the detergent
from the measured values using the graph.

Experimental Result②Abs
Absorbance

0.5280330
UV wavelenges（nm)Five concentrations were created and measured, and a calibration curve wascreated. High reliability because the correlation coefficient is close to 1.

0g 1180.1g 121

Moiarity（mol/L） Abs（－） 0.8
１．０×１０ー６ ０．０３１ 0.6 y = 25698x
R² = 0.9997
２．０×１０－６ ０．０６５ 0.4
３．０×１０－６ ０．０９７
0.2
１．０×１０－５ ０．３０９0
２．０×１０－５ ０．６０７
00.00001 0.00002 0.00003

aaaa0.3g 125

0The wavelength of ultraviolet raysabsorbed by stilbene was examinedwith a spectrophotometer. Measureusing the maximum absorbancewavelenges 310.

0.4g 1270.1g detergent was added to 10ml and measured with aspectrophotometer,and the amount of stilbene contained in
10ml was compared with four kinds of detergent. There wasa difference of about 10 times depending on the type ofdetergent.
Detergent type Content(g)Content rate（ｐｐｍ）
toppu
20.5
２．０７×１０－６
Laundry detergent １．１２×１０－５
112
ー５Haidoro D haita- １．３６×１０１３４0.6g 127
0.7g 133
It was found that the larger the amount ofstilbene, the more bright

Future Outlook① Take the most data and complete a more accurate graph(2) I would like to investigate the amount of stilbene included in the detergent otherthan the one I used
③ We will investigate the relationship between the amount of stilbene andultraviolet rays in the future and summarize it in a graph.

Attaku３．２５×１０ー５

３２１

References① Rasband,W.S., ImageJ, U.S. National Institutes of Health, Bethesda, Maryland, USA,
http://image.nih.gov/ij/,1997-2021② Schneider, C.A., Rasband, W.S., Eliceiri, K.W. “NIH Image to ImageJ: 25 years of image
analysis”. Nature Methods 9, 671-675,2021.