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Electromagnetic spectrum (電磁スペクトル)

Mount Usu / Sarobetsu post-mined peatland
From left: Crater basin in 1986 and 2006. Cottongrass / Daylily

[electromagnetic spectrum, visible light, ultraviolet, solar radiation]

Application of Electromagnetics

used electrical dynamo (or generator) and motor and invented wireless (radio) communication
Morse Samuel FB 1791-1872, USA, artist

1837 wire telegraphy (telegraph)
1838 Morse code (dot and dash)
1851 established submarine electric cable in the English Channel

Geissler Heinrich 1814-1879, Germany

invented the first cold cathode discharge tube and Geissler tube

Edison Thomas Alva 1847-1931, USA

1880? filament lamp
1880? electrical distribution force
(1882 the distance of electrical power transmission = 65 km)

Ferraris Galileo 1847-1897, Italy, technician

discovered the principle of rotating magnetic field → applied to produce induction motor (感応電動機)

Bell Alexander Graham 1847-1922, USA borne in Scotland

1876 telephone (contributed to the education for deaf persons)

Siemens, Ernst Werner von 1816-1892 Germany

Electrician and entrepreneur (established the predecessor of Siemens Co.)
1867 improved dynamo-electric generator based on self-excited principle
1880? electrical railroad

Parsons Sir Charles Algernon 1854-1931, England

1884 developed a compact steam turbine (蒸気タービン) for generator

Rateau Auguste 1863-1930, France, technician

1898 developed Rateau turbine based on fluid mechanics

Ferrié, Gustave 1868-1932, France, army general and scientist

1914- shakedown military-type radio communication network → contributed to the development

Deprez Marcel 1843-1918, France, physics (electrical technology)

developed long-distance power transport technique

Planté, Gaston 1834-1889, France

developed practicable lead battery

Gramme ZT 1826-1901, Belgium, electrician

invented DC (direct-current) dynamo → paved the way for practical use

Mascart Eleuthére 1837-1908: (electric) generator
Pacinotti, Antonio 1842-1912, Italy, physics (professor and senator)

invented DC (direct-current) dynamo

Baudot JME 1845-1903, France, inventor

baud that is a unit of modulating speed of telegram, originating from his name

Gaulard Lucien 1850-1888, France

electrical transformer (or voltage inverter), and electricity distribution system

Thomson Elihu 1853-1937, Use borne in England, electrician and inventor
Steinmetz Charles Proteus 1865-1923, USA borne in Germany, electrician and inventor

theory on AC (alternate current)

Wave phenomenon (波動現象)

Sound wave (音波)

= sonic wave and acoustic wave
= sound or sound wave (physics): vibration that propagates as an acoustic wave, through a transmission medium such as a gas, liquid or solid
= sound (physiology): the reception of such waves and their perception by the brain ⇒ noise

Wave model of sound (音の波モデル)

Longitudinal waves
wave Transverse waves

sound pressure (音圧) p (hPa), = sound pressure at crest
sound pressure effective value (音圧実効値) = p/√(2)

Sound energy density, w (音響エネルギー密度)

= sound density
= sound energy per unit volume (Pa)

w = pv/c

v: particle velocity in the direction of propagation
c: speed of sound

Frequency (Hz)
0 - Infrasound (with body resonance) - 10
infrasonic range (超低周波域)
10 - Infrasound or infrasonic waves (超低周波/可聴下音) - 20
20 - noise (defined by METI) - 100
20 - Low frequency noise (低周波騒音) - 200
200 - Non-low frequency audible noise (非低周波可聴騒音) - 20K
ultrasonic range (超音波領域)
20K < Ultrasound or ultrasonic waves (超音波)

Fig. The frequency spectrum of sound and its nomenclature. The definition is slightly different among the countries

Three elements of sound (音3要素)

a) (Tone) pitch (音程)
b) Tone (音色)
= tone quality, tone timbre, tone color
Overtone, or harmonics (harmonic sound) (倍音)
c) Loudness (音量)
Sound intensity
Def. Sound pressure (音圧)
Def. Sound pressure level (SPL, 音圧レベル), Lp (unit: decibel, dB)

Lp = 10·log10(p2/p02)

p: effective value of sound pressure (音圧実効値)
p0: reference sound pressure (基準音圧)

= 2 × 10-5 Pa (= 20 μPa)

Def. G-weighted sound pressure level (特性音圧レベル), LG

defined by ISO 7196
sensurous amplitude of sound evaluating low-frequency noise
LG = 10·log10(pG2/p02)

pG: effective value of G-weighted sound pressure

[ noise stress ]

Noise (騒音)

≈ unwanted sound
an undesirable component that obscures a wanted signal
Environmental noise: an accumulation of noise pollution wave
Fig. Low-frequency noise is derived from many potential sources, e.g., wind power, in everyday life.

Electromagnetics (electromagnetism, 電磁気学)

Electromagnetic field = magnetic field (磁場) + electric field (電場)
Def. magnetic field (磁場): a field around a magnet or something magnetic, in which it has a force to attract objects, such as electric charges, electric currents and magnetic materials, to itself
Def. electric(al) field (電場): a physical field that surrounds electrically charged particles where positive and negative particles are reacting with each other

Circuit (回路)

Schematic symbol (回路図記号)
→├─ diode
─▷◁─ gunn diode
→∫─ schottky-barrier diode
→│├ variable capacitor diode
PIN photo__PN photo__Tunnel___Light-emitting
diode_____ diode_____ diode____diode
circuit Zener diode
circuit Depletion type
(N channel Ver.)

Depletion type
(P channel Ver.)

Enhancement type
(N channel Ver.)

Enhancement type
(P channel Ver.)

Light amplification by
stimulated emission
of radiation diode




Inverter (NOT)

(N channel Ver.)

(P channel Ver.)


Bipolar transistor (NPN)

Bipolar transistor (PNP)

Uni-junction transistor

Insulated gate
bipolar transistor

Photo transistor

Gate turn-off thyristor

TRIode AC switch

Sillicon symmetrical switch

Electromagnetic spectrum (電磁スペクトル)

Fig. The electromagnetic energy spectrum
The entire range of wavelengths of electromagnetic radiation, most of which are not detectable by the human eye except in visible spectrum from ca 400-700 nm. Wavelengths shorter than the visible light contain large quantities of energy being harmful to living materials.

Common name_Range (nm)
X-ray_________10-1 - 101 (0.1-10)
UV ___A______102.30 - 102.45 (200-280)
______B______102.45 - 102.50 (280-320)
______C______102.50 - 102.58 (320-380)
Visible light____102.58 - 102.8 (380-630)
Infrared_______102.8 - 105 (630-100,000)
Radio_________105 - 109 (100,000-1,000,000,000)

Einstein's relation (アインシュタインの関係式), E = photon energy

= Planck–Einstein relation, Planck's energy–frequency relation, Planck relation or Planck equation

E = = h·c/λ

h: Planck constant
ν: frequency (sec-1) = c/λ
c: speed of light (3.00 × 108 m/s or 3.00 × 1010 cm/s)
λ: wavelength of light (m)

Photon flux density, PFD (光量子束密度)

Photosynthetic photon flux density, PPFD (光合成有効光量子束密度)

Visible light (可視光)

390 nm - 750 nm (standard human eye), used for photosynthesis
Spectrum of visible light
A rainbow, which indicates the spectrum of visible light well, at Kougarok in Seward Peninsula, Alaska, on August 11 2013 (Tsuyuzaki et al. 2018).
Illuminance, or lighting intensity (照度), Ev: lux (lx)
= wavelength-weighted by the luminosity function to correlate with human brightness perception

Table. Illuminance levels (lux)
> 100000: snow mountain, coast in summer
≈ 100000: clear and sunny >
≈ 20000-35000: cloudy at noon
≈ 400-500: under a fluorescent in a office
≈ 300: sunrise and sunset
≈ 10-20: 20 cm away from a candle
≈ 0.5-1: moonlight

Spectral luminous efficiency curve (比視感度曲線)

Fig. The scotopic (-----, 暗所) and the photopic (-----, 明所) curves of relative spectral luminous efficiency as specified by the International Commission of Illumination (normalized values)

Luminous flux (光束): lumen (lm), 1 lx = 1 lm/m²
Luminous intensity, lv (光度): 1 cd = 1 lm/sr²
Luminance or brightness (輝度): nt, 1 nt = 1 cd/m²
Photosynthecally active radiation (PAR, 光合成有効放射), W/m2
the spectral range from 400-700 nm that is used by plants in photosynthesis

direct light PAR = 0.43 × direct light
sky-light PAR = 0.57 × sky-light

(because shorter waves scatter more)

(Thimijan & Heins 1983)

Unit interconversion
Sun and sky, daylight: lx/54 = μmol·s-1m-2

[temperature (温度) | experimental protocol (実験プロトコル)]

Ultraviolet light, UV (紫外線)

A type of electromagnetic radiation beyond the wavelength of visible light, ranging from 180 (200) to 330 (380) nm.
UV-A (long wave, black light)
over 99% of UV on the earth surface. UV-A enhances the harmful effects of UVB,and is responsible for photosensitivity reactions. Cause of suntan.
UV-B (medium wave)
1% on the earth surface. UV-B causes sunburn and photochemical damages within cells, including DNA. Cause of sunburn.
UV-C (short wave, germicidal)
UV-C is filtered out by the ozone layer and does not reach the earth surface.
Spring Lecture: Introduction to the Ozone Depletion and the Effects of UV Radiation

UV-absorbing compounds (UVAC, 紫外線吸収物質)


UV-absorbing compound concentration


sample in the field

↓ dig up a whole or aboveground material
↓ pack into a plastic bag (or ziplock)
↓ store in a cooler with refrigerant and/or dry ice
↓ carry them back to lab. asap
↓ keep the samples in a freezer at about -70(80)°C until use
↓ freeze-dry

Leaf sample


Method 1

Leaf sample (1 cm² or known weight)

↓ add 15-ml methanol (HPLC grade)/HCl/H2O (90:1:1 volume)
↓ continuously stir and boil for 10 min.
↓ cool at room temperature for 15 min.
↓ filtrate with 90-µm mesh screens


Method 2

Leaf sample (known weight)

↓ agitate gently in the dark for 24 hr at 4°C in 1 ml methanolic extract*

* 3M HCl/H2O/MeOH = 1:3:16 (vol)

↓ centrifuge at ≈ 8000 g for > 5 min.



Absorbance is measured by a spectrophotometer. Dilution may be required.

Antocyanin compounds

Use the following equation:
(Absorbance measured at 530 nm) - 0.24 × (Absorbance measured at 653 nm)

Calibration curve is made by Cyanidin 3-glucoside (Cy-3-glc)
♦ Unit = g (mg, or µg) (determined as Cy-3-glc g)/(g leaf)

UV-B absorbing compounds

Absorbance measured at 300 nm

UV-A absorbing compounds

Absorbance measured at 350 nm

♦ Unit (UV-B and UV-B) = A/g (absorbance %/g leaf)

(Day 1993, Gould et al. 2000)

Radiation physics (放射線物理学)

the scientific discipline of the application of physics to the use of ionizing radiation in therapy and in diagnostic radiology; including, by extension, nuclear medicine applications, ultrasound and magnetic resonance imaging.
Interaction of ionizing radiation with matter