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H1_4.ai
Talk Letter
Vol.2 February 2009
Shimadzu Atomic Absorption Spectrophotometers
Reaching even greater heights
Unprecedented sensitivity, thanks to a newly developed 3D optical system
Advanced safety technology
System configuration evolving to suit the needs of the user
The newly developed 3D optical system is capable of flame: Pb 0.015 ppm detection, and furnace: Pb 0.00005 ppm detection.
Equipped with the world's first*1 vibration sensor, a multimode automatic gas leak check function, and other advanced safety technology.
Evolving from the basic flame model to suit the needs of the user. The dual atomizer system*2 is the world's smallest*1, and a furnace model is also available.
Easy-to-understand, user-friendly WizAArd software supports FDA 21 CFR Part 11 compliance.
*1 Survey by Shimadzu in November 2008.
*2 The optional auto atomizer changer is required.
Founded in 1875, Shimadzu Corporation, a leader in the development of advanced technologies, has a distinguished history of innovation built on the foundation of contributing to society through science and technology. We maintain a global network of sales, service, technical support and applications centers on six continents, and have established long-term
relationships with a host of highly trained distributors located
in over 100 countries. For information about Shimadzu, and to
contact your local office, please visit our Web site at
www.shimadzu.com
SHIMADZU CORPORATION. International Marketing Division
3. Kanda-Nishikicho 1-chome, Chiyoda-ku, Tokyo 101-8448, Japan
Phone: 81(3)3219-5641 Fax. 81(3)3219-5710
URL http://www.shimadzu.com
The contents of this brochure are subject to change without notice.
Printed in Japan 3295-11802-30ANS
(1) Halogen Lamp
The principle for light emission is the same as that for a standard incandescent bulb. Electric current is supplied to a filament, the filament
becomes hot, and light is emitted. The bulb in a halogen lamp is filled with
inert gas and a small amount of a halogen. While the tungsten used as the
alk Letter
filament evaporates due to the high temperature, the halide causes the tungsten to return to the filament. This helps create a bright light source with
a long service life. The emission intensity distribution of a halogen lamp can
UV Talk Letter
be approximated using Planck's law of radiation. Fig. 4 shows the emission
February 2009
intensity distribution for a temperature of 3,000 K. A halogen lamp offers
Relative intensity 0.2
The Structure of a Spectrophotometer
superior temporal stability, a service life of approx. 2,000 hours, and a relatively low cost. It has relatively high levels of each of the properties a) to
d) mentioned above.
1.The Measurement Principle Used by a Spectrophotometer
(2) Deuterium Lamp
A deuterium lamp is a discharge light source in which the bulb is filled with
Fig.4 Emission Intensity Distribution of Halogen Lamp (3,000K)
The basic measurement principle used by a spectrophotometer is relatively
deuterium (D2) at a pressure of several hundred pascals. Fig. 5 shows the
simple and easy to understand. I will explain the principle as it applies to
emission intensity distribution for a deuterium lamp. Although 400 nm is, in
solid samples and solution samples separately.
general, an approximate usage limit at the long wavelength end, because the
(1) Solid Samples
degree of attenuation at this end is quite low, light of wavelengths greater
As shown in Fig. 1, first the intensity of the measurement light beam, I0, is
than 400 nm is used. In the region beyond 400 nm, there are also large
measured without the sample set. Then the sample is set in the path of the
(protruding window: 1 mm thick)
(protruding window: 1 mm thick)
(protruding window: 1 mm thick)
numbers of bright line spectra. Among these, the bright line spectra at
measurement light beam, and the intensity of the light beam after it passes
486.0 nm and 656.1 nm are particularly intense, and can be used for the
through the sample, It, is measured.
wavelength calibration of spectrophotometers. The usage limit at the short
wavelength end is determined by the transmittance of the window material. In
The product of the transmittance, T, and 100 is the percent transmittance (%T).
Fig. 5, the graphs for cases where synthetic silica and UV glass are used for
the window material are given as examples.
(2) Solution Samples
As shown in Fig. 2, a cell containing solvent is set in the path of the
measurement light beam, and the intensity of the light beam after it passes through the cell, I0, is measured. Next, a cell containing a solution produced
Spectroscopy is the technique of splitting light that consists of various
by dissolving the sample in the solvent is set in the path of the measurement
wavelengths into components that correspond to those wavelengths. The
light beam, and the intensity of the light beam after it passes through the cell,
element that splits this light is called a dispersive element. Prisms and
Radiation intensity (
It, is measured. The transmittance, T, is given by equation (1), but with
diffraction gratings are typical dispersive elements. Prisms used to be
solution samples, it is more common to use the absorbance, Abs, which is
commonly used as the dispersive elements in spectrometers, but recently,
Fig.5 Emission Intensity Distribution of Deuterium Lamp1)
given by equation (2).
diffraction gratings have become the most commonly used type of dispersive
element. The diffraction gratings used in spectrophotometers have from
Equation (3), which expresses the relationship between the absorbance, Abs,
several hundred to approximately 2,000 parallel grooves per millimeter cut
and the sample concentration, C, is called the "Lambert-Beer law". There is a
into them at equal intervals. An example of a cross-section is shown in Fig. 6.
proportional relationship between the absorbance and concentration, and
If this diffraction grating is exposed to white light, because of interference,
Fig.1 Measurement Principle for Solid Samples
this forms the basis of quantitative analysis.
the white light is dispersed in a direction perpendicular to the grooves, and
light components of specific wavelengths are reflected only in specific
Here, ε is the sample's absorption coefficient and L is the cell's optical path length.
directions. This is illustrated in Fig. 7. λ1 to λ3 represent wavelengths. The
Fig.6 Cross Section of Diffraction Grating
The measurement method shown in Fig. 2 eliminates the influence of
wavelengths change continuously and so if a diffraction grating is exposed to
reflection from the cell surface and absorption by the solvent, and ensures
white light, it appears iridescent. The way that the clear side of a CD appears
that only the absorption due to the sample is measured.
to glitter with iridescence when it is exposed to light is based on the same
mechanism as the spectroscopy performed with a diffraction grating.
Monochromatic light is usually used for the measurement light beam shown in Fig. 1 and Fig. 2. Monochromatic light is light that consists of a single
A monochrometer consists of an entrance slit, an exit slit, and a diffraction
wavelength. To be precise, it has a spectral bandwidth (slit width). For
grating, as well as the mirrors and other parts that come with them. Although
Cell containing solvent
example, monochromatic light with a wavelength of 500 nm and a spectral
various types of monochrometers, which vary according to the arrangement
bandwidth of 2 nm is light that covers a wavelength interval (full width at half
of the elements, have been devised, Fig. 8 shows an example of the simplest
maximum) spanning 499 and 501 nm.
monochrometer configuration, which uses a concave diffraction grating. Light of varying wavelengths is projected from the output slit by rotating the
2.The Configuration of a Spectrophotometer
concave diffraction grating.
You will find from the above explanation that the indispensable elements of a
5.Sample Compartment
spectrophotometer consist, as shown in Fig. 3, of a light source, a
Diffraction grating
spectrometer, a sample compartment, and a detector. Although I said in the
Fig. 9 shows an example of a standard sample compartment. You can see
previous section that the sample is exposed to monochromatic light, there
that two light beams (indicated by red arrows in Fig. 9) pass through the
are instruments in which white light is passed through the sample before
compartment, and that this is therefore the sample compartment of a
Fig.7 Dispersion of Light by Diffraction Grating
being passed into the spectrometer. This method is employed in high-speed
"double-beam spectrophotometer". The monochromatic light that leaves the
photometry instruments that use array detectors.
spectrometer is split into two beams before it enters the sample
In the next sections, I will give an explanation of each element.
compartment. A spectrophotometer in which only one beam passes through
Cell containing sample solution
the sample compartment is called a "single-beam spectrophotometer". An explanation of the difference between single-beam and double-beam
Fig.2 Measurement Principle for Solution Samples
spectrophotometers is given in the Q&A of previous issue of UV Talk Letter.
The desirable properties of a light source are as follows:
Refer to this explanation if necessary.
a) Brightness across a wide wavelength rangeb) Stability over time
In a standard configuration, the sample compartment contains cell holders
c) A long service life
that, as shown in Fig. 9, hold square cells with optical path lengths of 10 mm.
The various accessories are attached by replacing these cell holder units or
Although there are no light sources that have all of these properties, the most
by replacing the entire sample compartment. Among spectrophotometers of
Concave diffraction
commonly used light sources at the moment are the halogen lamps used for
medium or higher grade that use photomultipliers, which will be described
the visible and near-infrared regions and the deuterium lamps used for the
later, as detectors, there are models for which large sample compartments
ultraviolet region. Apart from these, xenon flash lamps are sometimes used.
are made available in order to allow the analysis of large samples or the attachment of large accessories.
Fig.8 Graphic Illustration of a Concave-Grating Spectrometer
Fig.3 Configuration of Spectrophotometer
(1) Halogen Lamp
The principle for light emission is the same as that for a standard incandescent bulb. Electric current is supplied to a filament, the filament
becomes hot, and light is emitted. The bulb in a halogen lamp is filled with
inert gas and a small amount of a halogen. While the tungsten used as the
alk Letter
filament evaporates due to the high temperature, the halide causes the tungsten to return to the filament. This helps create a bright light source with
a long service life. The emission intensity distribution of a halogen lamp can
UV Talk Letter
be approximated using Planck's law of radiation. Fig. 4 shows the emission
February 2009
intensity distribution for a temperature of 3,000 K. A halogen lamp offers
Relative intensity 0.2
The Structure of a Spectrophotometer
superior temporal stability, a service life of approx. 2,000 hours, and a relatively low cost. It has relatively high levels of each of the properties a) to
d) mentioned above.
1.The Measurement Principle Used by a Spectrophotometer
(2) Deuterium Lamp
A deuterium lamp is a discharge light source in which the bulb is filled with
Fig.4 Emission Intensity Distribution of Halogen Lamp (3,000K)
The basic measurement principle used by a spectrophotometer is relatively
deuterium (D2) at a pressure of several hundred pascals. Fig. 5 shows the
simple and easy to understand. I will explain the principle as it applies to
emission intensity distribution for a deuterium lamp. Although 400 nm is, in
solid samples and solution samples separately.
general, an approximate usage limit at the long wavelength end, because the
(1) Solid Samples
degree of attenuation at this end is quite low, light of wavelengths greater
As shown in Fig. 1, first the intensity of the measurement light beam, I0, is
than 400 nm is used. In the region beyond 400 nm, there are also large
measured without the sample set. Then the sample is set in the path of the
(protruding window: 1 mm thick)
(protruding window: 1 mm thick)
(protruding window: 1 mm thick)
numbers of bright line spectra. Among these, the bright line spectra at
measurement light beam, and the intensity of the light beam after it passes
486.0 nm and 656.1 nm are particularly intense, and can be used for the
through the sample, It, is measured.
wavelength calibration of spectrophotometers. The usage limit at the short
wavelength end is determined by the transmittance of the window material. In
The product of the transmittance, T, and 100 is the percent transmittance (%T).
Fig. 5, the graphs for cases where synthetic silica and UV glass are used for
the window material are given as examples.
(2) Solution Samples
As shown in Fig. 2, a cell containing solvent is set in the path of the
measurement light beam, and the intensity of the light beam after it passes through the cell, I0, is measured. Next, a cell containing a solution produced
Spectroscopy is the technique of splitting light that consists of various
by dissolving the sample in the solvent is set in the path of the measurement
wavelengths into components that correspond to those wavelengths. The
light beam, and the intensity of the light beam after it passes through the cell,
element that splits this light is called a dispersive element. Prisms and
Radiation intensity (
It, is measured. The transmittance, T, is given by equation (1), but with
diffraction gratings are typical dispersive elements. Prisms used to be
solution samples, it is more common to use the absorbance, Abs, which is
commonly used as the dispersive elements in spectrometers, but recently,
Fig.5 Emission Intensity Distribution of Deuterium Lamp1)
given by equation (2).
diffraction gratings have become the most commonly used type of dispersive
element. The diffraction gratings used in spectrophotometers have from
Equation (3), which expresses the relationship between the absorbance, Abs,
several hundred to approximately 2,000 parallel grooves per millimeter cut
and the sample concentration, C, is called the "Lambert-Beer law". There is a
into them at equal intervals. An example of a cross-section is shown in Fig. 6.
proportional relationship between the absorbance and concentration, and
If this diffraction grating is exposed to white light, because of interference,
Fig.1 Measurement Principle for Solid Samples
this forms the basis of quantitative analysis.
the white light is dispersed in a direction perpendicular to the grooves, and
light components of specific wavelengths are reflected only in specific
Here, ε is the sample's absorption coefficient and L is the cell's optical path length.
directions. This is illustrated in Fig. 7. λ1 to λ3 represent wavelengths. The
Fig.6 Cross Section of Diffraction Grating
The measurement method shown in Fig. 2 eliminates the influence of
wavelengths change continuously and so if a diffraction grating is exposed to
reflection from the cell surface and absorption by the solvent, and ensures
white light, it appears iridescent. The way that the clear side of a CD appears
that only the absorption due to the sample is measured.
to glitter with iridescence when it is exposed to light is based on the same
mechanism as the spectroscopy performed with a diffraction grating.
Monochromatic light is usually used for the measurement light beam shown in Fig. 1 and Fig. 2. Monochromatic light is light that consists of a single
A monochrometer consists of an entrance slit, an exit slit, and a diffraction
wavelength. To be precise, it has a spectral bandwidth (slit width). For
grating, as well as the mirrors and other parts that come with them. Although
Cell containing solvent
example, monochromatic light with a wavelength of 500 nm and a spectral
various types of monochrometers, which vary according to the arrangement
bandwidth of 2 nm is light that covers a wavelength interval (full width at half
of the elements, have been devised, Fig. 8 shows an example of the simplest
maximum) spanning 499 and 501 nm.
monochrometer configuration, which uses a concave diffraction grating. Light of varying wavelengths is projected from the output slit by rotating the
2.The Configuration of a Spectrophotometer
concave diffraction grating.
You will find from the above explanation that the indispensable elements of a
5.Sample Compartment
spectrophotometer consist, as shown in Fig. 3, of a light source, a
Diffraction grating
spectrometer, a sample compartment, and a detector. Although I said in the
Fig. 9 shows an example of a standard sample compartment. You can see
previous section that the sample is exposed to monochromatic light, there
that two light beams (indicated by red arrows in Fig. 9) pass through the
are instruments in which white light is passed through the sample before
compartment, and that this is therefore the sample compartment of a
Fig.7 Dispersion of Light by Diffraction Grating
being passed into the spectrometer. This method is employed in high-speed
"double-beam spectrophotometer". The monochromatic light that leaves the
photometry instruments that use array detectors.
spectrometer is split into two beams before it enters the sample
In the next sections, I will give an explanation of each element.
compartment. A spectrophotometer in which only one beam passes through
Cell containing sample solution
the sample compartment is called a "single-beam spectrophotometer". An explanation of the difference between single-beam and double-beam
Fig.2 Measurement Principle for Solution Samples
spectrophotometers is given in the Q&A of previous issue of UV Talk Letter.
The desirable properties of a light source are as follows:
Refer to this explanation if necessary.
a) Brightness across a wide wavelength rangeb) Stability over time
In a standard configuration, the sample compartment contains cell holders
c) A long service life
that, as shown in Fig. 9, hold square cells with optical path lengths of 10 mm.
The various accessories are attached by replacing these cell holder units or
Although there are no light sources that have all of these properties, the most
by replacing the entire sample compartment. Among spectrophotometers of
Concave diffraction
commonly used light sources at the moment are the halogen lamps used for
medium or higher grade that use photomultipliers, which will be described
the visible and near-infrared regions and the deuterium lamps used for the
later, as detectors, there are models for which large sample compartments
ultraviolet region. Apart from these, xenon flash lamps are sometimes used.
are made available in order to allow the analysis of large samples or the attachment of large accessories.
Fig.8 Graphic Illustration of a Concave-Grating Spectrometer
Fig.3 Configuration of Spectrophotometer
The Structure of a Spectrophotometer
Applications The Relationship Between UV-VIS Absorption
and Structure of Organic Compounds
The Relationship Between UV-VIS Absorption and Structure of Organic Compounds
There are many colored organic compounds, such as dyes and pigments. How is it that these colors come about?
The light beams that pass through the sample compartment enter the detector, which is the last element in the spectrophotometer. Photomultipliers
There is a close relationship between the color of an organic compound and its structure. Here, I will explain this
and silicon photodiodes are typical detectors used with spectrophotometers
relationship using absorption spectra of organic compounds obtained with Shimadzu's UV-2550 UV-VIS
for the ultraviolet and visible regions. For the near-infrared region, PbS photoconductive elements have always been used in the past, but recently,
instruments incorporating InGaAs photodiodes have been sold. Silicon photodiode array detectors are used, in combination with the back
spectroscopy method, for high-speed photometry instruments.
1.The Relationship Between Conjugated Double
Photomultipliers and silicon photodiodes are described below.
Bond Systems and Absorption Peaks
Measurement-side
A photomultiplier is a detector that uses the fact that photoelectrons are
There are many organic compounds that have conjugated
discharged from a photoelectric surface when it is subjected to light (i.e., the
double bond systems (hereafter referred to as "conjugated
external photoelectric effect). The photoelectrons emitted from the
systems"), in which every other bond is a double bond. These
photoelectric surface repeatedly cause secondary electron emission in sequentially arranged dynodes, ultimately producing a large output for a
conjugated systems have a large influence on peak
Fig.1 Structures of Benzene, Naphthalene, and Anthracene
relatively small light intensity. The most important feature of a photomultiplier
wavelengths and absorption intensities.
is that it achieves a significantly high level of sensitivity that cannot be
Fig.9 Sample Compartment
Fig. 1 shows the structures of benzene, naphthalene, and
obtained with other optical sensors. If there is sufficient light intensity, this feature is not particularly relevant, but as the light intensity decreases, this
anthracene. Fig. 2 shows the absorption spectra obtained by
feature becomes increasingly useful. For this reason, photomultipliers are
dissolving these compounds in ethanol and analyzing the
used in high-grade instruments. The spectral sensitivity characteristics of a
resulting solutions. The concentrations were adjusted so that
photomultiplier are mainly determined by the material of the photoelectric
surface. Fig. 10 shows an example of the spectral sensitivity characteristics
the absorption intensities of the components were roughly the
of a multi-alkali photoelectric surface, a type of surface that is often used in
same. It can be seen in Fig. 2 that peak wavelengths tend to
be shifted toward the long wavelength region as the
(2) Silicon Photodiode
conjugated system gets larger. Table 11) gives the peak
A silicon photodiode is a detector that uses the fact that the electrical
wavelengths and the molar absorption coefficients of various
properties of a detector change when it is exposed to light (i.e., the internal
organic compounds. The molar absorption coefficient is a
photoelectric effect). Solar cells, which have attracted much attention
recently, use the same structure and principle as silicon photodiodes. In
measurement of how strongly a substance absorbs light. The
comparison with photomultipliers, silicon photodiodes offer advantages such
larger its value, the greater the absorption. With larger
as low cost, little locality of sensitivity in the light-receiving surface, and the
conjugated systems, the absorption peak wavelengths tend to
Fig.2 Absorption Spectra of Benzene, Naphthalene, and Anthracene
fact that a special power supply is not required. Even regarding sensitivity, if the light intensity is relatively large, they can obtain photometric data that is
be shifted toward the long wavelength region and the
Molar Absorption Coefficient
no inferior to that obtained with photomultipliers. Fig. 11 shows an example of
absorption peaks tend to be larger.
the spectral sensitivity characteristics of a silicon photodiode.
Ethylene (CH2=CH2)
2.Absorption Spectra of Food Dyes with
Large Conjugated Systems
Here, I have given an overview of the structure of UV-VIS
Fig. 3 shows the structures of food dyes New Coccine (Red
spectrophotometers. Due to space limitations, I have only described the
Radiation sensitivity of photoelectric surface (mA/W)
No. 102) and Brilliant Blue FCF (Blue No. 1) and Fig. 4 shows
basics. In the future, I plan to give more detailed explanations about
their absorption spectra. Food dyes tend to have large
specialized topics. I look forward to your continued interest.
Table 1 Absorption Peaks and Molar Absorption Coefficients of Various Organic Substances1)
conjugated systems, like those shown in Fig. 3, and therefore
their peak wavelengths tend to be shifted toward the long
Fig.10 Spectral Sensitivity Characteristics of a Photomultiplier2)
wavelength region, with peaks appearing in the visible region
1) Hamamatsu Photonics Deuterium Lamp Brochure
(400 to 700 nm). This is why they are recognized as colors.
2) Hamamatsu Photonics Photomultiplier Brochure
3) Hamamatsu Photonics Photodiode Brochure
Incidentally, the color that we see is the color that is not
absorbed by the substance (which is called the
"complementary color"). As shown in Fig. 4, New Coccine
absorbs blue and green light in the range 450 to 550 nm, and
Brilliant Blue FCF
so the complementary color, red, is seen by the human eye.
Fig.3 Structures of New Coccine and Brilliant Blue FCF
Brilliant Blue FCF absorbs yellow light in the range 560 to
650 nm and so blue is seen by the human eye.
Brilliant blue FCF
Light-receiving sensitivity (A/W)
Fig.11 Spectral Sensitivity Characteristics of a Silicon Photodiode3)
Tatsumi Sato (Ph, D,)
Spectroscopy Business Unit, Analytical & Measuring Instruments Division
Fig.4 Absorption Spectra of Food Dyes New Coccine and Brilliant Blue FCF
The Structure of a Spectrophotometer
Applications The Relationship Between UV-VIS Absorption
and Structure of Organic Compounds
The Relationship Between UV-VIS Absorption and Structure of Organic Compounds
There are many colored organic compounds, such as dyes and pigments. How is it that these colors come about?
The light beams that pass through the sample compartment enter the detector, which is the last element in the spectrophotometer. Photomultipliers
There is a close relationship between the color of an organic compound and its structure. Here, I will explain this
and silicon photodiodes are typical detectors used with spectrophotometers
relationship using absorption spectra of organic compounds obtained with Shimadzu's UV-2550 UV-VIS
for the ultraviolet and visible regions. For the near-infrared region, PbS photoconductive elements have always been used in the past, but recently,
instruments incorporating InGaAs photodiodes have been sold. Silicon photodiode array detectors are used, in combination with the back
spectroscopy method, for high-speed photometry instruments.
1.The Relationship Between Conjugated Double
Photomultipliers and silicon photodiodes are described below.
Bond Systems and Absorption Peaks
Measurement-side
A photomultiplier is a detector that uses the fact that photoelectrons are
There are many organic compounds that have conjugated
discharged from a photoelectric surface when it is subjected to light (i.e., the
double bond systems (hereafter referred to as "conjugated
external photoelectric effect). The photoelectrons emitted from the
systems"), in which every other bond is a double bond. These
photoelectric surface repeatedly cause secondary electron emission in sequentially arranged dynodes, ultimately producing a large output for a
conjugated systems have a large influence on peak
Fig.1 Structures of Benzene, Naphthalene, and Anthracene
relatively small light intensity. The most important feature of a photomultiplier
wavelengths and absorption intensities.
is that it achieves a significantly high level of sensitivity that cannot be
Fig.9 Sample Compartment
Fig. 1 shows the structures of benzene, naphthalene, and
obtained with other optical sensors. If there is sufficient light intensity, this feature is not particularly relevant, but as the light intensity decreases, this
anthracene. Fig. 2 shows the absorption spectra obtained by
feature becomes increasingly useful. For this reason, photomultipliers are
dissolving these compounds in ethanol and analyzing the
used in high-grade instruments. The spectral sensitivity characteristics of a
resulting solutions. The concentrations were adjusted so that
photomultiplier are mainly determined by the material of the photoelectric
surface. Fig. 10 shows an example of the spectral sensitivity characteristics
the absorption intensities of the components were roughly the
of a multi-alkali photoelectric surface, a type of surface that is often used in
same. It can be seen in Fig. 2 that peak wavelengths tend to
be shifted toward the long wavelength region as the
(2) Silicon Photodiode
conjugated system gets larger. Table 11) gives the peak
A silicon photodiode is a detector that uses the fact that the electrical
wavelengths and the molar absorption coefficients of various
properties of a detector change when it is exposed to light (i.e., the internal
organic compounds. The molar absorption coefficient is a
photoelectric effect). Solar cells, which have attracted much attention
recently, use the same structure and principle as silicon photodiodes. In
measurement of how strongly a substance absorbs light. The
comparison with photomultipliers, silicon photodiodes offer advantages such
larger its value, the greater the absorption. With larger
as low cost, little locality of sensitivity in the light-receiving surface, and the
conjugated systems, the absorption peak wavelengths tend to
Fig.2 Absorption Spectra of Benzene, Naphthalene, and Anthracene
fact that a special power supply is not required. Even regarding sensitivity, if the light intensity is relatively large, they can obtain photometric data that is
be shifted toward the long wavelength region and the
Molar Absorption Coefficient
no inferior to that obtained with photomultipliers. Fig. 11 shows an example of
absorption peaks tend to be larger.
the spectral sensitivity characteristics of a silicon photodiode.
Ethylene (CH2=CH2)
2.Absorption Spectra of Food Dyes with
Large Conjugated Systems
Here, I have given an overview of the structure of UV-VIS
Fig. 3 shows the structures of food dyes New Coccine (Red
spectrophotometers. Due to space limitations, I have only described the
Radiation sensitivity of photoelectric surface (mA/W)
No. 102) and Brilliant Blue FCF (Blue No. 1) and Fig. 4 shows
basics. In the future, I plan to give more detailed explanations about
their absorption spectra. Food dyes tend to have large
specialized topics. I look forward to your continued interest.
Table 1 Absorption Peaks and Molar Absorption Coefficients of Various Organic Substances1)
conjugated systems, like those shown in Fig. 3, and therefore
their peak wavelengths tend to be shifted toward the long
Fig.10 Spectral Sensitivity Characteristics of a Photomultiplier2)
wavelength region, with peaks appearing in the visible region
1) Hamamatsu Photonics Deuterium Lamp Brochure
(400 to 700 nm). This is why they are recognized as colors.
2) Hamamatsu Photonics Photomultiplier Brochure
3) Hamamatsu Photonics Photodiode Brochure
Incidentally, the color that we see is the color that is not
absorbed by the substance (which is called the
"complementary color"). As shown in Fig. 4, New Coccine
absorbs blue and green light in the range 450 to 550 nm, and
Brilliant Blue FCF
so the complementary color, red, is seen by the human eye.
Fig.3 Structures of New Coccine and Brilliant Blue FCF
Brilliant Blue FCF absorbs yellow light in the range 560 to
650 nm and so blue is seen by the human eye.
Brilliant blue FCF
Light-receiving sensitivity (A/W)
Fig.11 Spectral Sensitivity Characteristics of a Silicon Photodiode3)
Tatsumi Sato (Ph, D,)
Spectroscopy Business Unit, Analytical & Measuring Instruments Division
Fig.4 Absorption Spectra of Food Dyes New Coccine and Brilliant Blue FCF
Application The Relationship Between UV-VIS Absorption and Structure of Organic Compounds
Q&A What Is Stray Light?
3.The Influence of Functional Groups
Absorption peaks are also influenced by functional groups.
The term "stray light" appears in
Fig. 5 shows the absorption spectra of benzene, phenol, which
consists of a hydroxyl group bonded to a benzene ring, and p-
product brochures. What is this exactly?
nitrophenol, which consists of a hydroxyl group and a nitro
group bonded to a benzene ring. The functional groups
influence the conjugated systems, causing the absorption
Red: p-Nitrophenol
peaks to appear at longer wavelengths than the peak
wavelength of benzene, although they do not go beyond
400 nm and enter the visible region. The color of organic
compounds, then, is influenced more strongly by the size of
the conjugated system.
"Stray light" is light of any wavelength contained in the light used in a spectrophotometer
4.Absorption Spectra of Compounds with a Large
Fig.5 Absorption Spectra of Benzene, Phenol, and p-Nitrophenol
that differs from the set target wavelength. It is expressed as the ratio (%) of the total
Molecular Framework and a Small Conjugated System
amount of light of wavelengths other than the target wavelength to the amount of light of
Fig. 7 shows the absorption spectra of prednisolone, which is
used as a pharmaceutical, and benzene. Although
A the target wavelength. Fig.1 shows the graphic illustration of stray light. In Fig. 1, the blue
prednisolone has a large molecular framework, its conjugated
section corresponds to the target wavelength and the gray section corresponds to stray
system is small and so its peak wavelengths are not shifted
light. Checks for stray light are performed using filters (e.g., NaI solution filter and NaNO3
greatly toward the long wavelength region, and its peaks
solution filter) that do not allow light of specific wavelengths to pass through. The
appear at roughly the same position as those of benzene.
measurement wavelength is set to the wavelength that should be completely absorbed by
5.The Reason for the Shift Toward the Long
the filter, the actual transmittance is measured, and from this the amount of stray light is
Wavelength Region
I have shown the relationship between molecular structure and
Fig.6 Structures of Phenol and p-Nitrophenol
Stray light is a problem because it influences the linearity of the calibration curves used
absorption spectra. Why, then, does the peak wavelength tend
for quantitative analysis. This influence is hardly observed at all in low-absorbance
to be shifted toward the long wavelength region as the size of
regions, but if there is a lot of stray light in high-absorbance, high-concentration regions,
the conjugated system increases? Let us consider the
the calibration curve is prone to bend. (See Fig. 2.) The wavelength of stray light differs
relationship between the energy of light and the movement of
from the target wavelength and so it is not absorbed by the sample. Light of wavelengths
other than the target wavelength passes through the sample without being absorbed and
Light exhibits properties of both waves and particles
so, in accordance with the Lambert-Beer law, the measured absorbance is less than the
(photons). The energy of one photon is expressed as hc/λ,
Red: Prednisolone
true value. Even if the calibration curve is bent, quantitative analysis is still possible using
where h is Planck's constant, c is the speed of light, and λ is
quadratic expressions. However, because the sizes of changes in absorbance with
the wavelength.
respect to the sizes of changes in sample concentration decrease, the quantitative error
Absorption in the ultraviolet and visible regions is related to
the transition of electrons. "Transition" refers to the switching
In general, the level of stray light is lower with double-monochromator instruments than it
of an electron from one state of motion to another. The state of
is with single-monochromator instruments.
motion of the π electrons in the conjugated system changes
Fig.7 Absorption Spectra of Prednisolone and Benzene
more easily than that of the σ electrons that form the molecular frameworks. If a photon collides with a π electron, that π electron readily changes to a different state of motion. This is
true even if the photon has only a small amount of energy. The
π electrons in relatively large conjugated systems are more easily affected by low-energy photons. Transition expresses
the way that the energy of photons is absorbed by electrons. If
a photon has a relatively small amount of energy, the value of
hc/λ for that photon is relatively small, and therefore the value of λ is relatively large. λ is observed as the absorption
wavelength and so, if there is a conjugated system, peaks
tend to appear in regions where λ is large, i.e., the long
Fig.8 Structures of Prednisolone and Benzene
wavelength region.
1) Masayoshi Nakahara:
Fig.1 Graphic Illustration of Stray Light
Fig.2 Change in Calibration Curve due to Stray Light
Applications Development Center, Analytical Applications Department,
"The Science of Color", Baifukan (2002), p. 108
:Target wavelength :Stray light
:Low stray light instrument :High stray light instrument
Analytical & Measuring Instruments Division
Application The Relationship Between UV-VIS Absorption and Structure of Organic Compounds
Q&A What Is Stray Light?
3.The Influence of Functional Groups
Absorption peaks are also influenced by functional groups.
The term "stray light" appears in
Fig. 5 shows the absorption spectra of benzene, phenol, which
consists of a hydroxyl group bonded to a benzene ring, and p-
product brochures. What is this exactly?
nitrophenol, which consists of a hydroxyl group and a nitro
group bonded to a benzene ring. The functional groups
influence the conjugated systems, causing the absorption
Red: p-Nitrophenol
peaks to appear at longer wavelengths than the peak
wavelength of benzene, although they do not go beyond
400 nm and enter the visible region. The color of organic
compounds, then, is influenced more strongly by the size of
the conjugated system.
"Stray light" is light of any wavelength contained in the light used in a spectrophotometer
4.Absorption Spectra of Compounds with a Large
Fig.5 Absorption Spectra of Benzene, Phenol, and p-Nitrophenol
that differs from the set target wavelength. It is expressed as the ratio (%) of the total
Molecular Framework and a Small Conjugated System
amount of light of wavelengths other than the target wavelength to the amount of light of
Fig. 7 shows the absorption spectra of prednisolone, which is
used as a pharmaceutical, and benzene. Although
A the target wavelength. Fig.1 shows the graphic illustration of stray light. In Fig. 1, the blue
prednisolone has a large molecular framework, its conjugated
section corresponds to the target wavelength and the gray section corresponds to stray
system is small and so its peak wavelengths are not shifted
light. Checks for stray light are performed using filters (e.g., NaI solution filter and NaNO3
greatly toward the long wavelength region, and its peaks
solution filter) that do not allow light of specific wavelengths to pass through. The
appear at roughly the same position as those of benzene.
measurement wavelength is set to the wavelength that should be completely absorbed by
5.The Reason for the Shift Toward the Long
the filter, the actual transmittance is measured, and from this the amount of stray light is
Wavelength Region
I have shown the relationship between molecular structure and
Fig.6 Structures of Phenol and p-Nitrophenol
Stray light is a problem because it influences the linearity of the calibration curves used
absorption spectra. Why, then, does the peak wavelength tend
for quantitative analysis. This influence is hardly observed at all in low-absorbance
to be shifted toward the long wavelength region as the size of
regions, but if there is a lot of stray light in high-absorbance, high-concentration regions,
the conjugated system increases? Let us consider the
the calibration curve is prone to bend. (See Fig. 2.) The wavelength of stray light differs
relationship between the energy of light and the movement of
from the target wavelength and so it is not absorbed by the sample. Light of wavelengths
other than the target wavelength passes through the sample without being absorbed and
Light exhibits properties of both waves and particles
so, in accordance with the Lambert-Beer law, the measured absorbance is less than the
(photons). The energy of one photon is expressed as hc/λ,
Red: Prednisolone
true value. Even if the calibration curve is bent, quantitative analysis is still possible using
where h is Planck's constant, c is the speed of light, and λ is
quadratic expressions. However, because the sizes of changes in absorbance with
the wavelength.
respect to the sizes of changes in sample concentration decrease, the quantitative error
Absorption in the ultraviolet and visible regions is related to
the transition of electrons. "Transition" refers to the switching
In general, the level of stray light is lower with double-monochromator instruments than it
of an electron from one state of motion to another. The state of
is with single-monochromator instruments.
motion of the π electrons in the conjugated system changes
Fig.7 Absorption Spectra of Prednisolone and Benzene
more easily than that of the σ electrons that form the molecular frameworks. If a photon collides with a π electron, that π electron readily changes to a different state of motion. This is
true even if the photon has only a small amount of energy. The
π electrons in relatively large conjugated systems are more easily affected by low-energy photons. Transition expresses
the way that the energy of photons is absorbed by electrons. If
a photon has a relatively small amount of energy, the value of
hc/λ for that photon is relatively small, and therefore the value of λ is relatively large. λ is observed as the absorption
wavelength and so, if there is a conjugated system, peaks
tend to appear in regions where λ is large, i.e., the long
Fig.8 Structures of Prednisolone and Benzene
wavelength region.
1) Masayoshi Nakahara:
Fig.1 Graphic Illustration of Stray Light
Fig.2 Change in Calibration Curve due to Stray Light
Applications Development Center, Analytical Applications Department,
"The Science of Color", Baifukan (2002), p. 108
:Target wavelength :Stray light
:Low stray light instrument :High stray light instrument
Analytical & Measuring Instruments Division
Talk Letter
Vol.2 February 2009
Shimadzu Atomic Absorption Spectrophotometers
Reaching even greater heights
Unprecedented sensitivity, thanks to a newly developed 3D optical system
Advanced safety technology
System configuration evolving to suit the needs of the user
The newly developed 3D optical system is capable of flame: Pb 0.015 ppm detection, and furnace: Pb 0.00005 ppm detection.
Equipped with the world's first*1 vibration sensor, a multimode automatic gas leak check function, and other advanced safety technology.
Evolving from the basic flame model to suit the needs of the user. The dual atomizer system*2 is the world's smallest*1, and a furnace model is also available.
Easy-to-understand, user-friendly WizAArd software supports FDA 21 CFR Part 11 compliance.
*1 Survey by Shimadzu in November 2008.
*2 The optional auto atomizer changer is required.
Founded in 1875, Shimadzu Corporation, a leader in the development of advanced technologies, has a distinguished history of innovation built on the foundation of contributing to society through science and technology. We maintain a global network of sales, service, technical support and applications centers on six continents, and have established long-term
relationships with a host of highly trained distributors located
in over 100 countries. For information about Shimadzu, and to
contact your local office, please visit our Web site at
www.shimadzu.com
SHIMADZU CORPORATION. International Marketing Division
3. Kanda-Nishikicho 1-chome, Chiyoda-ku, Tokyo 101-8448, Japan
Phone: 81(3)3219-5641 Fax. 81(3)3219-5710
URL http://www.shimadzu.com
The contents of this brochure are subject to change without notice.
Printed in Japan 3295-11802-30ANS
Source: https://www.shimadzu.ch/sites/default/files/vol2.pdf
Health Care and Cost of Medication for Inflammatory BowelDisease in the Rhein-Main Region, Germany: A Multicenter,Prospective, Internet-based Study I. Blumenstein, MD,*† H. Bock, MD,†‡ C. Weber, MD,†‡ A. Rambow, MD,†‡ W. Tacke, MD,†‡ R. Kihn, MD,†‡R. Pfaff, MD,†‡ S. Orlemann, MD,†‡ R. Schaeffer, MD,†‡ O. Schro¨der, MD*† A. Dignaß, MD†PF. Hartmann, MD†§ J. Stein, MD, PhD*†¶
SPANYOL NYELV EMELT SZINTŰ ÍRÁSBELI VIZSGA 2006. november 2. 8:00 2006. november 2. I. Olvasott szöveg értése Időtartam: 70 perc Pótlapok száma Tisztázati Piszkozati OKTATÁSI ÉS KULTURÁLIS ÉRETTSÉGI VIZSGA emelt szint — írásbeli vizsga 0621 I. Olvasott szöveg értése