JP2006078281A - Method for evaluating number density of floating particle having particular particle diameter - Google Patents

Method for evaluating number density of floating particle having particular particle diameter Download PDF

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JP2006078281A
JP2006078281A JP2004261432A JP2004261432A JP2006078281A JP 2006078281 A JP2006078281 A JP 2006078281A JP 2004261432 A JP2004261432 A JP 2004261432A JP 2004261432 A JP2004261432 A JP 2004261432A JP 2006078281 A JP2006078281 A JP 2006078281A
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particle size
particles
background noise
size distribution
particle
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JP4079374B2 (en
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Masashige Shoji
正成 庄司
Delaunay Jean-Jacques
ジャック ドロネー ジャン
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Nippon Telegraph and Telephone Corp
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Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for using an existing light scattering particle counter or an equivalent counting principle, removing an effect of background noise particles, and conveniently and precisely evaluating the number density of particles having a particular particle diameter when the number density of the particles having the particular particle diameter is measured and evaluated under an outdoor environment in which the background noise particles exist. <P>SOLUTION: The number density of the objective particles is precisely evaluated by evaluating a particle diameter distribution of the background noise particles from the entire particle diameter distribution and removing its effect. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

本発明は特定粒径をもつ浮遊粒子の個数濃度の評価方法に係る。   The present invention relates to a method for evaluating the number concentration of suspended particles having a specific particle size.

特開平５−２４０７６８号公報（特許第３１１３７２０号）JP-A-5-240768 (Patent No. 3113720)

従来、光散乱式自動粒子計測器を用いると大気中に浮遊する粒子の個数濃度の粒径分布（粒子径とその個数濃度の関係)は比較的簡単に計測することができていた。しかしながら、この種の装置は、例えば屋外大気中に浮遊する例えば特定の花粉のような特定粒径の粒子の個数濃度を計測しようとした場合、対象粒子の個数濃度が環境に通常存在する同程度の粒径のバックグラウンドノイズ粒子濃度に比べて大きな場合を除いて、その濃度を精度良く計測することは不可能であり、粒径分布の他に別の物理量を計測し、評価する必要があった。例えば、特許文献１には、粒径分布の測定とともに偏光度という別の物理量も同時に計測し、これら２つの計測データを同時にもちいることによって花粉粒子をバックグラウンドノイズ粒子から識別する屋外大気中の花粉粒子濃度を計測する装置について記載されている。このように従来の技術では粒径分布のみで対象粒子濃度を評価することはできず、装置、データ処理ともに通常の光散乱式自動粒子計測器と比べて複雑となり、結果としてシステム全体として高価なものにならざるを得なかった。   Conventionally, when a light scattering type automatic particle measuring device is used, the particle size distribution of the number concentration of particles floating in the atmosphere (the relationship between the particle size and the number concentration) can be measured relatively easily. However, when this type of device is intended to measure the number concentration of particles with a specific particle size, such as specific pollen, floating in the outdoor air, the number concentration of target particles is comparable to that normally present in the environment. Unless the particle size is larger than the background noise particle concentration, it is impossible to accurately measure the concentration, and it is necessary to measure and evaluate another physical quantity in addition to the particle size distribution. It was. For example, in Patent Document 1, another physical quantity called polarization degree is measured at the same time as measurement of particle size distribution, and pollen particles are identified from background noise particles by using these two measurement data simultaneously. An apparatus for measuring pollen particle concentration is described. As described above, the conventional technology cannot evaluate the target particle concentration only by the particle size distribution, and both the apparatus and the data processing are complicated as compared with a normal light scattering type automatic particle measuring instrument, and as a result, the entire system is expensive. I had to become something.

本発明は上記の問題に鑑み、屋外等バックグランドノイズ粒子の存在する環境下において、特定の粒径をもつ粒子の個数濃度を測定評価する場合に、既存の光散乱式粒子計数器あるいはそれと同等の計数原理を有する粒子計数器の測定データをもちいて、バックグラウンドノイズ粒子の影響を取り除いて特定粒径の粒子の個数濃度を簡便に精度良く評価する方法を提供することを目的とする。   In view of the above problems, the present invention is an existing light scattering type particle counter or an equivalent thereof when measuring and evaluating the number concentration of particles having a specific particle size in the presence of background noise particles such as outdoors. It is an object of the present invention to provide a method for easily and accurately evaluating the number concentration of particles having a specific particle size by removing the influence of background noise particles using measurement data of a particle counter having the above counting principle.

従来、光散乱式粒子計測原理を用いた屋外での特定粒子計側では、個数濃度の粒径分布データからは対象粒径程度の粒径をもつ粒子の濃度、すなわち、対象粒子とバックグラウンドノイズ粒子とを合わせた濃度という情報しか利用されていなかった。   Conventionally, on the specific particle meter side using the light scattering type particle measurement principle, the concentration of particles having a particle size of the target particle size from the particle size distribution data of the number concentration, that is, the target particle and background noise Only information on the concentration combined with the particles was used.

本発明では、全体の粒経分布からバックグラウンドノイズ粒子の粒径分布を評価してこの影響を取り除くことによって、対象粒子の個数濃度を高精度に評価する。具体的には次のような手順をとる。
（１）バックグラウンドノイズ粒子の個数濃度粒径分布の関数形を仮定する。（但し、場所、時間依存性を考慮していくつかの変数を含む関数とする）
（２）全粒径分布データから（１）の関数を決定する。
（３）（２）の関数をもちいて測定対象粒子の粒径範囲のバックグラウンドノイズ粒子濃度を評価する。
（４）（３）の評価を測定対象粒子の粒径範囲の個数濃度データから差し引く。 In the present invention, the particle size distribution of the background noise particles is evaluated from the overall particle size distribution and this influence is removed, whereby the number concentration of the target particles is evaluated with high accuracy. Specifically, the following procedure is taken.
(1) A function shape of the number concentration particle size distribution of background noise particles is assumed. (However, it is a function including several variables in consideration of location and time dependence.)
(2) The function of (1) is determined from the total particle size distribution data.
(3) The background noise particle concentration in the particle size range of the particles to be measured is evaluated using the function of (2).
(4) The evaluation in (3) is subtracted from the number concentration data in the particle size range of the particles to be measured.

本発明はさらに、全粒径分布データ値をもちいて、バックグラウンドノイズ粒子粒経分布の関数形及び測定対象粒子粒径分布の関数形を同時に決定し、バックグラウンドノイズ粒子の影響を取り除いて測定対象粒子の個数濃度を評価することも可能である。   The present invention further uses the total particle size distribution data value to simultaneously determine the function shape of the background noise particle size distribution and the function shape of the particle size distribution to be measured, and remove the influence of the background noise particles. It is also possible to evaluate the number concentration of target particles.

以上の手段をもちいることによって、バックグラウンドノイズ粒子の存在する環境下においても、光散乱式の計測原理による個数濃度の粒径分布データのみから対象粒子の個数濃度を精度良く評価することができる。   By using the above means, it is possible to accurately evaluate the number concentration of target particles from only the particle size distribution data of the number concentration based on the light scattering measurement principle even in the environment where background noise particles exist. .

バックグラウンドノイズ粒子の個数濃度粒径分布の関数形を全粒子粒径分布データより決定することにより、バックグラウンドノイズ粒子の浮遊している環境下においても測定対象粒子の粒径領域におけるバックグラウンドノイズ粒子の影響を取り除き、これによって測定対象粒子の個数濃度を精度良く評価することができる。   By determining the function form of the number concentration particle size distribution of the background noise particles from the total particle size distribution data, the background noise in the particle size region of the particle to be measured even in the environment where the background noise particles are floating By removing the influence of the particles, the number concentration of the particles to be measured can be accurately evaluated.

以下に本発明の実施例を示す。   Examples of the present invention are shown below.

大気中におけるスギ花粉粒子の計測に適用する例を示す。大気中におけるバックグラウンドとしての浮遊粒子の個数濃度の粒径分布ｄＮ／ｄｒは、半径ｒが０．１μｍよりも大きな範囲において、典型的には   An example of application to measurement of cedar pollen particles in the atmosphere will be shown. The particle size distribution dN / dr of the number concentration of suspended particles as a background in the atmosphere is typically in the range where the radius r is larger than 0.1 μm.

Figure 2006078281
と表されることが知られている（Jungeの指数分布則）。ここではこれをバックグラウンドノイズ粒子の粒径濃度分布関数として用いる。なお、ａ、ｂは環境に応じて決まる定数であり、同一地点であっても一般に時間によって変動する。
Figure 2006078281
 (Junge's exponential distribution law). Here, this is used as a particle size concentration distribution function of the background noise particles. Note that a and b are constants determined according to the environment, and generally vary with time even at the same point.

図１にこの分布を模式的に示す。また、図2にスギ花粉が少量浮遊する環境における粒径分布図を示す。日本のスギ花粉は直径２５〜３５μｍ程度の範囲の粒径分布を持つので、ｒ＝１２．５〜１７．５μｍ程度の範囲に分布が出現することとなる。このようにバックグラウンドノイズ粒子に対してスギ花粉濃度の十分高くない場合、スギ花粉程度の粒径の粒子数濃度を計測してもバックグラウンドノイズ粒子の影響によって精度の高いスギ花粉濃度計測を行うことは不可能である。光散乱式粒子計測においては，チャンバー内に導入した大気にレーザー光等を照射し一個一個の粒子からの散乱光を電気変換して出力パルスを生成し、この出カパルスを計数することによって計測データを得る。実際には、閾値Ｖｔを設定し、ある一定時間にその閾値以上のパルス数が何個であるかを計数することとなる。ここで、粒径とパルス高さの値との関係は事前に決定してあるため、ある閾値Ｖｔ以上のパルスの個数はある半径ｒ以上の粒子の個数に対応し、その時間内に計測している大気の体積値で除すことによってある半径ｒ以上の粒子の個数濃度がデータとして得られることとなる。 FIG. 1 schematically shows this distribution. FIG. 2 shows a particle size distribution diagram in an environment where a small amount of cedar pollen floats. Japanese cedar pollen has a particle size distribution in the range of about 25 to 35 μm in diameter, so that the distribution appears in the range of r = 12.5 to 17.5 μm. In this way, when the cedar pollen concentration is not sufficiently high with respect to the background noise particles, even if the particle number concentration of the particle size of the cedar pollen is measured, the cedar pollen concentration measurement with high accuracy is performed by the influence of the background noise particles. It is impossible. In light scattering particle measurement, laser light is irradiated to the atmosphere introduced into the chamber, the scattered light from each particle is electrically converted to generate output pulses, and the output data is counted to count the measurement data. Get. In practice, sets the threshold value V t, the number of pulses above its threshold a certain time is counting how many pieces. Here, since the relationship between the value of the particle diameter and the pulse height are determined in advance, corresponding to the number of a certain threshold value V t or more pulses radius r or more number of grains in the measurement in that time By dividing by the volume value of the atmospheric air, the number concentration of particles having a radius r or more can be obtained as data.

ここで、図３のように３つの閾値Ｖｔ１、Ｖｔ２、Ｖｔ３をスギ花粉粒子の粒径範囲外に、またＶｔ４、Ｖｔ５、をスギ花粉の粒径分布範囲に設定することによって、５種類の粒子数濃度Ｎ１、Ｎ２、Ｎ３、Ｎ４、Ｎ５（個／ｍ３）を測定する。閾値Ｖｔ１〜Ｖｔ５に対応する粒径をｒ１〜ｒ５とすると、Ｎ２−Ｎ３は粒径がｒ２とｒ３との間の範囲に入る粒子数濃度、Ｎ１−Ｎ２は粒径がｒ１とｒ２との間の範囲に入る粒子数濃度となる。数１式をｒ１からｒ２まで積分したものと、ｒ２からｒ３まで積分したものはこれらに等しいため、 Here, as shown in FIG. 3, by setting the three threshold values V t1 , V t2 , V t3 outside the cedar pollen particle size range, and V t4 , V t5 , the cedar pollen particle size distribution range. Five types of particle number concentrations N 1 , N 2 , N 3 , N 4 , and N 5 (pieces / m 3 ) are measured. When the particle diameters corresponding to the thresholds V t1 to V t5 are r 1 to r 5 , N 2 -N 3 is the number concentration of particles falling within the range between r 2 and r 3 , N 1 -N 2 Is a particle number concentration in which the particle diameter falls within the range between r 1 and r 2 . Since the integration of Equation 1 from r 1 to r 2 and the integration of r 2 to r 3 are equal to these,

Figure 2006078281
Figure 2006078281

Figure 2006078281
なる関係を得る。これらから未知数ａ、ｂを決定し、この測定環境におけるバックグラウンド特性の関数を決定することができる。次に決定したａ、ｂをもちいてスギ花粉の粒径分布範囲ｒ４からｒ５で数１式右辺を積分することによって、スギ花粉粒径分布範囲のバックグラウンドノイズ粒子濃度Ｎｂを求めて、
Figure 2006078281
 Get a relationship. From these, the unknowns a and b can be determined, and a function of the background characteristics in this measurement environment can be determined. Next, the background noise particle concentration N b in the cedar pollen particle size distribution range is obtained by integrating the right side of Equation 1 in the particle size distribution range r 4 to r 5 of the cedar pollen using the determined a and b. ,

Figure 2006078281
これをスギ花粉粒径分布範囲の全粒子数密度計測結果Ｎ４、Ｎ５から差し引くことによってバックグラウンドノイズ粒子の影響を取り除いて正確なスギ花粉濃度Ｎｃを決定することができる。
Figure 2006078281
 By subtracting this from the total particle number density measurement results N 4 and N 5 in the cedar pollen particle size distribution range, the influence of background noise particles can be removed to determine an accurate cedar pollen concentration N c .

Figure 2006078281
Figure 2006078281

大気中におけるスギ花粉粒子の計測に適用する例を示す。測定した値が狭い粒径範囲に分布しているのであれば、大気中におけるバックグラウンドとしての浮遊粒子の個数濃度の粒径分布ｄＮ／ｄｒを測定範囲で   An example of application to measurement of cedar pollen particles in the atmosphere will be shown. If the measured value is distributed in a narrow particle size range, the particle size distribution dN / dr of the number concentration of suspended particles as the background in the atmosphere is measured in the measurement range.

Figure 2006078281
と仮定できる。ここでａ、ｂは環境に応じて決まる定数であり、同一地点であっても一般に時間の関数となる。
Figure 2006078281
 Can be assumed. Here, a and b are constants determined according to the environment, and are generally functions of time even at the same point.

図４にこの分布を模式的に示す。また、図５にスギ花粉が少量浮遊する環境における粒径分布図を示す。日本のスギ花粉は直径２５〜３５μｍ程度の範囲の粒径分布を持つので、ｒ＝１２．５〜１７．５μｍ程度の範囲に分布が出現することとなる。このようにバックグラウンドノイズ粒子に対してスギ花粉濃度の十分高くない場合、スギ花粉程度の粒径の粒子数濃度を計測してもバックグラウンドノイズ粒子の影響によって精度の高いスギ花粉濃度計測を行うことは不可能である。光散乱式粒子計測においては、チャンバー内に導入した大気にレーザー光等を照射し一個一個の粒子からの散乱光を電気変換して出力パルスを生成し、この出力パルスを計数することによって計測データを得る。実際には、閾値Ｖｔを設定し、その閾値以上のパルス数が何個であるかを計数することとなる。ここで、粒径とパルス高さの値との関係は事前に決定してあるため、ある閾値Ｖｔ以上のパルスの個数はある半径ｒ以上の粒子の個数に対応し、計測している大気の体積値で除すことによってある半径ｒ以上の粒子の個数濃度が決定されることとなる。ここで、図５のように４つの閾値を設定する。（Ｖｔ２、Ｖｔ３，をスギ花粉の粒径分布範囲程度に、またＶｔ１、Ｖｔ４をその外側に設定する。）４種類の粒子数濃度Ｎ１、Ｎ２、Ｎ３、Ｎ４（個／ｍ３）が計測データとして得られるが、閾値Ｖｔ１〜Ｖｔ４に対応する粒径をｒ１〜ｒ４とすると、Ｎ１−Ｎ２は粒径がｒ１とｒ２との間の範囲に入る粒子数濃度、Ｎ３−Ｎ４は粒径がｒ３とｒ４との間の範囲に入る粒子数濃度となる。数６式をｒ１からｒ２まで積分したものと、ｒ３からｒ４まで積分したものはこれらに等しいため、 FIG. 4 schematically shows this distribution. FIG. 5 shows a particle size distribution diagram in an environment where a small amount of cedar pollen floats. Japanese cedar pollen has a particle size distribution in the range of about 25 to 35 μm in diameter, so that the distribution appears in the range of r = 12.5 to 17.5 μm. In this way, when the cedar pollen concentration is not sufficiently high with respect to the background noise particles, even if the particle number concentration of the particle size of the cedar pollen is measured, the cedar pollen concentration measurement with high accuracy is performed by the influence of the background noise particles. It is impossible. In light scattering particle measurement, laser light is irradiated to the atmosphere introduced into the chamber, the scattered light from each particle is electrically converted to generate output pulses, and the measurement data is counted by counting the output pulses. Get. In practice, it sets the threshold value V t, so that the number of pulses above the threshold are counted how many pieces. Here, since the relationship between the particle size and the pulse height value is determined in advance, the number of pulses equal to or greater than a certain threshold value Vt corresponds to the number of particles equal to or greater than a certain radius r and is measured. By dividing by the volume value, the number concentration of particles having a radius r or more is determined. Here, four threshold values are set as shown in FIG. (V t2 and V t3 are set to the particle size distribution range of cedar pollen, and V t1 and V t4 are set to the outside thereof.) Four types of particle number concentrations N 1 , N 2 , N 3 , N 4 ( Pcs / m 3 ) is obtained as measurement data. If the particle sizes corresponding to the threshold values V t1 to V t4 are r 1 to r 4 , N 1 -N 2 has a particle size between r 1 and r 2. N 3 -N 4 is a particle number concentration falling within the range between r 3 and r 4 . Since the equation 6 integrated from r 1 to r 2 and the equation integrated from r 3 to r 4 are equal to these,

Figure 2006078281
Figure 2006078281

Figure 2006078281
なる関係を得る。これらから未知数ａ、ｂを決定し、この測定環境におけるバックグラウンド特性を決定することができる。次に決定したａ、ｂをもちいてスギ花粉の粒径分布範囲ｒ２からｒ３で数６式右辺を積分することによって、スギ花粉粒径分布範囲のバックグラウンドノイズ粒子濃度Ｎｂを求めて、
Figure 2006078281
 Get a relationship. From these, the unknowns a and b can be determined, and the background characteristics in this measurement environment can be determined. By integrating the equation (6) right-hand side r 3 from the grain size distribution range r 2 of cedar pollen by using then determined a, the b, seeking background noise particle concentration N b of cedar pollen particle size distribution range ,

Figure 2006078281
これをスギ花粉粒径分布範囲の全粒子数密度計測結果Ｎ２〜Ｎ３から差し引くことによってバックグラウンドノイズ粒子の影響を取り除いて正確なスギ花粉濃度Ｎｃを決定することができる。
Figure 2006078281
 This can eliminate the influence of background noise particles by subtracting from the total number of particles of cedar pollen particle size distribution range Density measurement results N 2 to N 3 to determine the exact cedar pollen concentration N c.

Figure 2006078281
Figure 2006078281

大気中におけるスギ花粉粒子の計測に適用する例を示す。大気中におけるバックグラウンドとしての浮遊粒子の個数濃度の粒径分布ｄＮ／ｄｒは、半径ｒが０．１μｍよりも大きな範囲において、典型的には An example of application to measurement of cedar pollen particles in the atmosphere will be shown. The particle size distribution dN / dr of the number concentration of suspended particles as a background in the atmosphere is typically in the range where the radius r is larger than 0.1 μm.

Figure 2006078281
と表されることが知られている（Jungeの指数分布則）。ここではこれをバックグラウンドノイズ粒子の粒径濃度分布関数として用いる。なおａ、ｂは環境に応じて決まる定数であり、同―地点であっても一般に時間によって変動する。
Figure 2006078281
 (Junge's exponential distribution law). Here, this is used as a particle size concentration distribution function of the background noise particles. Note that a and b are constants determined according to the environment, and generally vary with time even at the same point.

図７にこの分布を模式的に示す。また、スギ花粉の粒径にバラツキがある場合、スギ花粉の粒径分布ｄＮｐ／ｄｒとしてガウス分布をもちいて FIG. 7 schematically shows this distribution. In addition, when there is variation in the particle size of cedar pollen, a Gaussian distribution is used as the particle size distribution dN p / dr of cedar pollen.

Figure 2006078281
と、表すことができる。ここで、ｒｍは平均値、σは標準偏差である。従って、計測される全粒子数濃度ｄＮｔ／ｄｒは、
Figure 2006078281
 It can be expressed as. Here, the r m average, sigma is the standard deviation. Therefore, the total particle number concentration dN t / dr measured is

Figure 2006078281
となる。
Figure 2006078281
 It becomes.

図８にスギ花粉が少量浮遊する環境における粒径分布図を示す。日本のスギ花粉は直径２５〜３５μｍ程度の範囲の粒径分布を持つので、ｒ＝１２．５〜１７．５μｍ程度の範囲に分布が出現することとなる。このようにバックグラウンドノイズ粒子に対してスギ花粉濃度の十分高くない場合、スギ花粉程度の粒径の粒子数濃度を計測してもバックグラウンドノイズ粒子の影響によって精度の高いスギ花粉濃度計測を行うことは不可能である。光散乱式粒子計測においては、チャンパー内に導入した大気にレーザー光等を照射し一個一個の粒子からの散乱光を電気変換して出カパルスを生成し、この出力パルスを計数することによって計測データを得る。実際には、閾値Ｖｔを設定し、ある一定時間にその閾値以上のパルス数が何個であるかを計数することとなる。ここで、粒径とパルス高さの値との関係は事前に決定してあるため、ある閾値Ｖｔ以上のパルスの個数はある半径ｒ以上の粒子の個数に対応し、その時間内に計測している大気の体積値で除すことによってある半径ｒ以上の粒子の個数濃度がデータとして得られることとなる。ここで、図９のように３つの閾値Ｖｔ３、Ｖｔ４、Ｖｔ５をスギ花粉粒子の粒径範囲内に、またＶｔ１、Ｖｔ２、Ｖｔ６、をスギ花粉の粒径分布範囲外に設定することによって、６種類の粒子数濃度Ｎｉ（ｉ＝１〜６）（個／ｍ３）を測定する。閾値Ｖｔ１〜Ｖｔ６に対応する粒径をｒ１〜ｒ６とすると、Ｎｉ（ｉ＝１〜６）は粒径がｒｉ（ｉ＝１〜６）以上である粒子数濃度である。数１３式をｒｉ（ｉ＝１〜５）からｒ６の範囲で積分したものは、Ｎｉ−Ｎ６（ｉ＝１〜５）に等しいため、 FIG. 8 shows a particle size distribution diagram in an environment where a small amount of cedar pollen floats. Japanese cedar pollen has a particle size distribution in the range of about 25 to 35 μm in diameter, so that the distribution appears in the range of r = 12.5 to 17.5 μm. In this way, when the cedar pollen concentration is not sufficiently high with respect to the background noise particles, even if the particle number concentration of the particle size of the cedar pollen is measured, the cedar pollen concentration measurement with high accuracy is performed by the influence of the background noise particles. It is impossible. In light-scattering particle measurement, measurement data is generated by irradiating the atmosphere introduced into the chamber with laser light, etc., and electrically converting the scattered light from each particle to generate output pulses and counting the output pulses. Get. In practice, sets the threshold value V t, the number of pulses above its threshold a certain time is counting how many pieces. Here, since the relationship between the value of the particle diameter and the pulse height are determined in advance, corresponding to the number of a certain threshold value V t or more pulses radius r or more number of grains in the measurement in that time By dividing by the volume value of the atmospheric air, the number concentration of particles having a radius r or more can be obtained as data. Here, as shown in FIG. 9, the three threshold values V t3 , V t4 , V t5 are within the particle size range of the cedar pollen particles, and V t1 , V t2 , V t6 are outside the particle size distribution range of the cedar pollen. By setting, six types of particle number concentrations N i (i = 1 to 6) (pieces / m 3 ) are measured. If the particle diameters corresponding to the threshold values V t1 to V t6 are r 1 to r 6 , N i (i = 1 to 6) is a particle number concentration having a particle diameter of r i (i = 1 to 6) or more. . Since the equation (13) integrated in the range from r i (i = 1 to 5) to r 6 is equal to N i −N 6 (i = 1 to 5),

Figure 2006078281
なる５つの式を得る（ｉ＝１〜５）。これらの式から未知数ａ，ｂ，ｃ，ｒｍ，σを決定し、この測定環境におけるバックグラウンド特性の粒子濃度分布関数及びスギ花粉粒子濃度分布の関数を決定することができる。決定したｃ，ｒｍ，σをもちいてスギ花粉の粒径分布範囲を含む範囲で数１２式右辺を積分することによって、バックグラウンドノイズ粒子の影響を取り除いた正確なスギ花粉濃度Ｎｃを決定することができる。
Figure 2006078281
 The following five equations are obtained (i = 1 to 5). The unknowns a, b, c, r m , and σ can be determined from these equations, and the background concentration particle concentration distribution function and the cedar pollen particle concentration distribution function in this measurement environment can be determined. By using the determined c, r m , and σ and integrating the right side of Formula 12 in the range including the particle size distribution range of the cedar pollen, the exact cedar pollen concentration N c is determined by removing the influence of background noise particles. can do.

Figure 2006078281
Figure 2006078281

以上説明したように、従来の光散乱式粒子計数器等をもちいて、適切な閾値レベルを設定することによってバックグラウンドノイズ粒子の存在する環境下においてもその影響を簡便に取り除いて精度良く特定粒径をもつ対象粒子の個数濃度を評価することができる。   As described above, by using a conventional light scattering particle counter or the like, by setting an appropriate threshold level, the influence can be easily removed even in an environment where background noise particles are present, and specific particles can be accurately obtained. The number concentration of target particles having a diameter can be evaluated.

本発明の実施例１における、大気中のバックグラウンドノイズ粒子粒径分布図である。It is a background noise particle size distribution map in the atmosphere in Example 1 of the present invention. 本発明の実施例１における、スギ花粉及びバックグラウンドノイズ粒子の粒径分布図である。It is a particle size distribution map of a cedar pollen and background noise particle | grains in Example 1 of this invention. 本発明の実施例１における、スギ花粉及びバックグラウンドノイズ粒子の粒径分布図に閾値を設定した図である。It is the figure which set the threshold value to the particle size distribution figure of a cedar pollen and background noise particle | grains in Example 1 of this invention. 本発明の実施例２における、大気中のバックグラウンドノイズ粒子粒径分布図である。It is a background noise particle size distribution map in the atmosphere in Example 2 of the present invention. 本発明の実施例２における、スギ花粉及びバックグラウンドノイズ粒子の粒径分布図である。It is a particle size distribution map of a cedar pollen and background noise particle | grains in Example 2 of this invention. 本発明の実施例２における、スギ花粉及びバックグラウンドノイズ粒子の粒径分布図に閾値を設定した図である。It is the figure which set the threshold value to the particle size distribution figure of a cedar pollen and background noise particle | grains in Example 2 of this invention. 本発明の実施例３における、大気中のバックグラウンドノイズ粒子粒径分布図である。It is a background noise particle size distribution map in the atmosphere in Example 3 of the present invention. 本発明の実施例３における、スギ花粉及びバックグラウンドノイズ粒子の粒径分布図である。It is a particle size distribution map of a cedar pollen and background noise particle | grains in Example 3 of this invention. 本発明の実施例３における、スギ花粉及びバックグラウンドノイズ粒子の粒径分布図に閾値を設定した図である。It is the figure which set the threshold value to the particle size distribution figure of a cedar pollen and background noise particle | grains in Example 3 of this invention.

Claims (6)

測定対象となる特定の粒径をもつ測定対象粒子とバックグラウンドノイズとなるバックグラウンドノイズ粒子が存在する環境下において、空気中の浮遊粒子に光を照射して散乱光を受光素子によって受信し、浮遊粒子の個数濃度を計測する方法において、
計測した全浮遊粒子の粒径分布データ値から測定環境に依存したバックグラウンドノイズ粒子の影響を取り除いて、測定対象粒子の個数濃度を評価することを特徴とする特定粒径をもつ浮遊粒子の個数濃度の評価方法。 In an environment where there are measurement target particles with a specific particle size to be measured and background noise particles as background noise, light is radiated to suspended particles in the air and scattered light is received by the light receiving element, In the method of measuring the number concentration of suspended particles,
The number of suspended particles with a specific particle size characterized by evaluating the number concentration of particles to be measured by removing the influence of background noise particles depending on the measurement environment from the measured particle size distribution data of all suspended particles Concentration evaluation method. 測定対象粒子の粒径分布範囲外における浮遊粒子の粒径分布データ値に基づいて、測定対象粒子粒径分布範囲でのバックグラウンドノイズ粒子の影響を評価することを特徴とする請求項１に記載の特定粒径をもつ浮遊粒子の個数濃度の評価方法。 2. The influence of background noise particles in the particle size distribution range of the measurement target particle is evaluated based on the particle size distribution data value of the suspended particles outside the particle size distribution range of the measurement target particle. Of evaluating the number concentration of suspended particles having a specific particle size. 全粒径分布データ値をもちいて、バックグラウンドノイズ粒子粒経分布の関数形及び測定対象粒子粒径分布の関数形を同時に決定し、バックグラウンドノイズ粒子の影響を取り除いて測定対象粒子の個数濃度を評価することを特徴とする請求項１に記載の特定粒径をもつ浮遊粒子の個数濃度の評価方法。 Using the total particle size distribution data, the function shape of the background noise particle size distribution and the function shape of the particle size distribution to be measured are simultaneously determined, and the influence of the background noise particles is removed to determine the number concentration of the particles to be measured. The method for evaluating the number concentration of suspended particles having a specific particle size according to claim 1. 測定対象となる特定の粒径をもつ測定対象粒子とバックグラウンドノイズとなるバックグラウンドノイズ粒子が存在する環境下において、空気中の浮遊粒子に光を照射して散乱光を受光素子によって受信し、浮遊粒子の個数濃度を計測する方法において、
適切に設定したｎ個の閾値で計測される全浮遊粒子に対する粒径分布データ値に基づいて、その環境に依存したバックグラウンドノイズ粒子の影響を取り除いて測定対象粒子の個数濃度を評価することを特徴とする特定粒径をもつ浮遊粒子の個数濃度の評価方法。 In an environment where there are measurement target particles with a specific particle size to be measured and background noise particles as background noise, light is radiated to suspended particles in the air and scattered light is received by the light receiving element, In the method of measuring the number concentration of suspended particles,
Based on the particle size distribution data value for all suspended particles measured with n threshold values set appropriately, the influence of background noise particles depending on the environment is removed to evaluate the number concentration of particles to be measured. A method for evaluating the number concentration of suspended particles having a specific specific particle size. ｎ個の粒径分布データ値をもちいて、測定対象粒子の粒径分布範囲外の粒径分布データ値のみに基づき、測定対象粒子の粒径分布範囲におけるバックグラウンドノイズ粒子の個数濃度を評価することによって、バックグラウンドノイズ粒子の影響を取り除いて測定対象粒子の個数濃度を評価することを特徴とする請求項４に記載の特定粒径をもつ浮遊粒子の個数濃度の評価方法。 Using n particle size distribution data values, the number concentration of background noise particles in the particle size distribution range of the measurement target particle is evaluated based only on the particle size distribution data value outside the particle size distribution range of the measurement target particle. 5. The method for evaluating the number concentration of suspended particles having a specific particle size according to claim 4, wherein the number concentration of the measurement target particles is evaluated by removing the influence of background noise particles. ｎ個の粒径分布データ値をもちいて、バックグラウンドノイズ粒子粒径分布の関数形及び測定対象粒子粒径分布の関数形を同時に決定し、バックグラウンドノイズ粒子の影響を取り除いて測定対象粒子の個数濃度を評価することを特徴とする請求項４に記載の特定粒径をもつ浮遊粒子の個数濃度の評価方法。 Using the n particle size distribution data values, the function shape of the background noise particle size distribution and the function shape of the particle size distribution to be measured are simultaneously determined, and the influence of the background noise particles is removed to 5. The method for evaluating the number concentration of suspended particles having a specific particle size according to claim 4, wherein the number concentration is evaluated.
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CN106644868A (en) * 2017-02-08 2017-05-10 河海大学 Measuring method for peripheral interface concentration of two-dimensional non-convex random aggregates
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JP2018017680A (en) * 2016-07-29 2018-02-01 パナソニックＩｐマネジメント株式会社 Air cleaning device
CN106644868A (en) * 2017-02-08 2017-05-10 河海大学 Measuring method for peripheral interface concentration of two-dimensional non-convex random aggregates
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