JPS5892931A - Spectroscopic analyzer - Google Patents

Spectroscopic analyzer

Info

Publication number
JPS5892931A
JPS5892931A JP19324081A JP19324081A JPS5892931A JP S5892931 A JPS5892931 A JP S5892931A JP 19324081 A JP19324081 A JP 19324081A JP 19324081 A JP19324081 A JP 19324081A JP S5892931 A JPS5892931 A JP S5892931A
Authority
JP
Japan
Prior art keywords
switch
output
sensitivity
converter
spectrometer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP19324081A
Other languages
Japanese (ja)
Other versions
JPS6246822B2 (en
Inventor
Kikuo Sasaki
佐々木 菊夫
Kenji Kawasaki
健治 川崎
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shimadzu Corp
Shimazu Seisakusho KK
Original Assignee
Shimadzu Corp
Shimazu Seisakusho KK
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shimadzu Corp, Shimazu Seisakusho KK filed Critical Shimadzu Corp
Priority to JP19324081A priority Critical patent/JPS5892931A/en
Publication of JPS5892931A publication Critical patent/JPS5892931A/en
Publication of JPS6246822B2 publication Critical patent/JPS6246822B2/ja
Granted legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/27Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands using photo-electric detection ; circuits for computing concentration
    • G01N21/274Calibration, base line adjustment, drift correction

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Mathematical Physics (AREA)
  • Theoretical Computer Science (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)

Abstract

PURPOSE:To enable to perform a self-adjustment of sensitivity simply through simple operation of a switch. CONSTITUTION:A light source HCL is lighted to match a wavelength of a spectrometer and adjust a slit width. At the beginning, a switch SW1 is brought to ON, and thereby at a stage when matching of the wavelength of the spectrometer MC and adjusting of the slit width are completed, a photo detector PM has a diode applying voltage which is adjusted so that a photometry output Vi becomes equal to a reference voltage Vr, and an input voltage of a DC-DC converter is stored in a capacitor of a sample hold circuit SH. Thus, even if the switch SW1 is opened since that, the sensitivity of the PM is maintained to a sensitivity produced right before the SW1 is opened, and under said condition, Vi is equal to Vr. The Vr is set so that an output of an absorbance converter LOG attains O in the case of Vi=Vr, and as a result, a required adjustment is automatically completed through the above operation.

Description

【発明の詳細な説明】 本発明は分光分析装置において特に測光系の感度調整装
置に関する。
DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sensitivity adjustment device for a photometric system in a spectroscopic analyzer.

従来の分光分析装置では測光系の感度調整は表示部の表
示を見ながら手動的に可変抵抗等を調節することによっ
て行っていた。本発明はこのような手動的な感度調整を
ワンタッチで自動的に行えるようにすることを目的とし
てなされた。
In conventional spectroscopic analyzers, the sensitivity of the photometric system is adjusted by manually adjusting variable resistors and the like while viewing the display. The present invention has been made with the object of enabling such manual sensitivity adjustment to be performed automatically with a single touch.

本発明の目的を具体的に説明するため第1図に示す従来
例について述べる。第1図は原子吸光分析装置を示し、
HCLは検出しようとする元素の輝線を出している光源
、ATMは試料原子化部の炎、MCは分光器、PMは光
検出器のフォトマルチプライヤ、PAはプリアンプ、L
OGは測光出力を吸光度値に変換する対数変換器、Mは
表示部で、DDは検出器PMのダイ、ノードに高電圧を
与える直流−直流変換器であり、可変抵抗VRIを調節
して検出器PMの感度を調整している。この調整手順は
光源HCLを点灯し、試料を供給しない状態で分光器の
波長を目的の輝線波長に合せ、スリット幅を調整した後
、LO()の出力■0が略0になるようにVRIを調節
する。このような調整は吸光度変換器LOGの直線性の
良好な範囲に同変換器への入力v1を設定するためであ
り、更には吸収のない状態で表示部Mの表示がOである
ことが望ましいからである。しかし分光分析に先立って
一々このよりな調整を目視に頼り手動で行うことは大へ
ん面倒である。本発明は単なるスイツチの一操作によっ
て上述した感度調整を自動的に行い得るようにするもの
である。以下実施例によって本発明を説明する。
In order to specifically explain the purpose of the present invention, a conventional example shown in FIG. 1 will be described. Figure 1 shows an atomic absorption spectrometer,
HCL is the light source emitting the bright line of the element to be detected, ATM is the flame of the sample atomization section, MC is the spectrometer, PM is the photomultiplier of the photodetector, PA is the preamplifier, L
OG is a logarithmic converter that converts the photometric output into an absorbance value, M is a display section, and DD is a DC-DC converter that applies high voltage to the die and node of the detector PM, and is detected by adjusting the variable resistor VRI. The sensitivity of the device PM is being adjusted. This adjustment procedure turns on the light source HCL, adjusts the wavelength of the spectrometer to the desired emission line wavelength without supplying a sample, adjusts the slit width, and then adjusts the VRI so that the output of LO() becomes approximately 0. Adjust. Such adjustment is to set the input v1 to the absorbance converter LOG within a range where the linearity of the converter is good, and furthermore, it is desirable that the display M shows O when there is no absorption. It is from. However, it is very troublesome to perform these fine adjustments manually, relying on visual inspection, prior to spectroscopic analysis. The present invention allows the above-mentioned sensitivity adjustment to be performed automatically by simply operating a switch. The present invention will be explained below with reference to Examples.

第2図は本発明の一実施例装置を示す。第1図の各部と
同じ部分には第1図と同じ符号をつけて一々の説明は略
す。プリアンプFAの出力即ち測光出力Viは吸光度変
換部LOG及び誤差増幅器EAの一方の入力端子に印加
される。誤°差増幅器の他方の入力端子には基準電圧V
rが印加しである。SHはサンプルホールド回路であり
、SWlはサンプリングスイッチである。サンプルホー
ルド回路SHの出力が直流−直流変換器DDで直流高電
圧に変換されて検出器PMのダイノードに印加される。
FIG. 2 shows an embodiment of the present invention. Components that are the same as those in FIG. 1 are given the same reference numerals as in FIG. 1, and detailed description thereof will be omitted. The output of the preamplifier FA, ie, the photometric output Vi, is applied to one input terminal of the absorbance converter LOG and the error amplifier EA. The other input terminal of the error amplifier is connected to the reference voltage V.
r is applied. SH is a sample hold circuit, and SWl is a sampling switch. The output of the sample hold circuit SH is converted into a DC high voltage by a DC-DC converter DD and applied to the dynode of the detector PM.

従ってスイッチE1wlを閉じると、測光出力v1が基
準電圧Vrと比較され、両者の差が直流−直流変換器D
Dを介して検出器PMにフィードバックされて■1がV
rに等くなるように動作する。V i = V rのと
き吸光度変換器LOGの出力が0になるようにVrが設
定しである。
Therefore, when the switch E1wl is closed, the photometric output v1 is compared with the reference voltage Vr, and the difference between the two is determined by the DC-DC converter D.
is fed back to the detector PM via D, and ■1 becomes V
It operates so that it is equal to r. Vr is set so that the output of the absorbance converter LOG becomes 0 when V i =V r.

以上の構成で感度調整は次のように行われる。With the above configuration, sensitivity adjustment is performed as follows.

光源HCLを点灯し、分光器MCの波長合せとスリット
幅の調整を行う。こ\までは従来装置と変らない。この
間においてスイッチSWIをオンにしておく。感度調整
操作としてはこの後SWIをオフするだけでよい。当初
スイッチSW1がオンになっているので、分光器MCの
波長合せ、スリット幅調整が終った段階で光検出器PM
は測光出力v1が基準電圧Vrと等しくなるようにダイ
ノード印加電圧が調整されており、直流−直流変換器D
Dの入力電圧はサンプルホールド回路SHのコンデンサ
Cに記憶されている。従ってその後スイッチ8vrlを
開いてもPMの感゛度はSwlを開く直前の感度に保持
され、この状態にあってはVi=Vrである。Vrは吸
光度変換器LOGの出力がVi=’VrのときOとなる
ように設定してあ。
The light source HCL is turned on, and the wavelength and slit width of the spectroscope MC are adjusted. Up to this point, there is no difference from conventional equipment. During this time, switch SWI is kept on. As a sensitivity adjustment operation, it is sufficient to simply turn off the SWI after this. Initially, the switch SW1 is on, so when the wavelength matching of the spectrometer MC and the slit width adjustment are completed, the photodetector PM is turned on.
The voltage applied to the dynode is adjusted so that the photometric output v1 is equal to the reference voltage Vr, and the DC-DC converter D
The input voltage of D is stored in capacitor C of sample-and-hold circuit SH. Therefore, even if the switch 8vrl is opened thereafter, the sensitivity of PM is maintained at the sensitivity immediately before opening Swl, and in this state, Vi=Vr. Vr is set so that the output of the absorbance converter LOG becomes O when Vi='Vr.

るので、以上の操作で所要の調整が自動的に終り、操作
はスイッチSwlのオンオフだけで第1図に示しだ可変
抵抗VRIを表示部の表示が0になるように調節すると
云った手間は全く不要である。
Therefore, the necessary adjustments are automatically completed with the above operations, and the hassle of adjusting the variable resistor VRI shown in Figure 1 so that the display shows 0 is eliminated by simply turning the switch Swl on and off. Totally unnecessary.

第3図は本発明の他の実施例を示す。この実施例の装置
も原子吸光分析装置であるが、輝線スペクトル光源1(
CLの他に連続スペクトル光源りを用いてパックグラウ
ンド補正を行うようになっている。これら2種の光源の
光はハーフミラ−HMを通して同一光路上に乗り、試料
原子化部ATM、分光器MCを通り光検出器PMに入射
するようにな、っている。ハーフミラ−HMは円周方向
に透過率と反射率の比が変っており、回転の角位置を変
えることで両光源の光の比率を変えられるようにしであ
る。。MTはハーフミラ−HMの角位置をの信号により
制御されている。D、Cは信号選別器で発振器OBCの
出力信号により制御され、プリアンプPAの出力(測光
出力)をHC−Lの光によるものe)1とDの光による
ものeDとに選別する。
FIG. 3 shows another embodiment of the invention. The apparatus of this example is also an atomic absorption spectrometer, but the emission line spectrum light source 1 (
In addition to the CL, a continuous spectrum light source is used to perform background correction. The light from these two types of light sources travels on the same optical path through the half mirror HM, passes through the sample atomization section ATM and the spectroscope MC, and enters the photodetector PM. The half mirror HM has a ratio of transmittance and reflectance that changes in the circumferential direction, and by changing the angular position of rotation, the ratio of light from both light sources can be changed. . MT is controlled by a signal for the angular position of the half mirror HM. D and C are signal selectors that are controlled by the output signal of the oscillator OBC and select the output (photometric output) of the preamplifier PA into HC-L light e)1 and D light eD.

θH1θDは夫々吸光度変換器LOG:L、LOG2で
吸光度値eHL及びeDLに変換されて引算回路5UB
Iによって引算されバックグラウンド補正された吸光度
値が表示部Mlにおいて表示される。
θH1θD are converted into absorbance values eHL and eDL by the absorbance converters LOG:L and LOG2, respectively, and then sent to the subtraction circuit 5UB.
The absorbance value subtracted by I and background corrected is displayed on the display M1.

SHは第2図におけると同じサンプルホールド回路であ
るが、スイッチSWIは手動でなくビームバランス制御
部BBCから指令信号で自動的に操作され名。誤差増幅
器KAには連続スペクトル光源りの光の測光出力θDが
入力されて基準電圧Vrと比較される。従って光検出器
PMは9])=Vrとなるように感度調整がなされる。
SH is the same sample and hold circuit as in Fig. 2, but the switch SWI is not operated manually but automatically by a command signal from the beam balance controller BBC. The photometric output θD of the light from the continuous spectrum light source is input to the error amplifier KA and compared with the reference voltage Vr. Therefore, the sensitivity of the photodetector PM is adjusted so that 9])=Vr.

引算器5UBIの出力vOが比較器CPI及びCF2に
印加されて基準電圧+War及び−rVcrと比較され
る。CPUは入力vOがVo)十Verのとき出力1.
その他出力0.CP2は入力VoがvO(−V e r
のとき出力IIその他出力0である。
The output vO of the subtracter 5UBI is applied to comparators CPI and CF2 and compared with reference voltages +War and -rVcr. The CPU outputs 1 when the input vO is Vo)10 Ver.
Other output 0. CP2 input Vo is vO(-V e r
When , output II and other outputs are 0.

従って−Vcr≦Vo≦VcrのときはCPI。Therefore, when -Vcr≦Vo≦Vcr, it is CPI.

CF2の出力は共に00ビ一ムバランス制御部BBCは
CPl、、CF2(7)出力が共ニo、即ち−Vc r
 < V o≦VQrとなるようにモー2りMTを駆動
しでハーフミラ−)IMの角位置を設定する。前述した
ようにハーフミラ−HMは円周方向に透過率と反射率と
の比率が変っている゛ので、この動作により引算器5U
BIの出力■0の絶対値がVer以下となるように調整
される。この動作は試料が供給されていないときに輝線
光源HCLの光と連続スペクトル光源りの光の測光出力
を略一致させ吸光度信号が0となるように2つの光源の
光をバランスさせるものである。スイッチSw2はビー
ムバランス制御部BBCの動作をスタートさせる手動ス
イッチである。
The outputs of CF2 are both 00, the beam balance control unit BBC is CPl, and the output of CF2 (7) is 0, that is, -Vcr.
The angular position of the half mirror (IM) is set by driving the motor MT so that <Vo≦VQr. As mentioned above, in the half mirror HM, the ratio of transmittance and reflectance changes in the circumferential direction, so this operation causes the subtracter 5U to change.
Adjustment is made so that the absolute value of the BI output ■0 is equal to or less than Ver. This operation balances the light from the two light sources so that when no sample is supplied, the photometric outputs of the light from the bright line light source HCL and the light from the continuous spectrum light source approximately match, and the absorbance signal becomes 0. The switch Sw2 is a manual switch that starts the operation of the beam balance controller BBC.

第4図は上述ビームバランス制御部BBCの動作のフロ
ーチャートである。装置のオペレータは2つの光源HC
L及びDを点灯し、分光器Mの波長設定、スリット幅調
整を行った後スイッチSw2を押すだけでよい。スイッ
チSV2オン(第4図イ)によってサンプルホールド回
路SHのサンプリングスイッチSw1がオンされ(第4
図口)、判定ハにおいて比較器cp1.CP2の各出力
VC1,■C2ともOか否か判定され、判定Noのとき
はハーフミラ−HMを回転させ(第4図二)、判定ハが
YESになったら8wlオフとしく第4図ホ)サンプル
ホールド回路EIHをホールド状態にする。以上でBB
Cの動作が稍り、分析装置の感度調整が終る。
FIG. 4 is a flowchart of the operation of the beam balance controller BBC mentioned above. The operator of the device uses two light sources HC.
All you have to do is turn on L and D, set the wavelength of the spectrometer M, adjust the slit width, and then press the switch Sw2. By turning on the switch SV2 (FIG. 4A), the sampling switch Sw1 of the sample and hold circuit SH is turned on (the fourth
figure), the comparator cp1. It is determined whether each output VC1, ■C2 of CP2 is O or not. If the determination is No, the half mirror HM is rotated (Fig. 4, 2), and when the determination is YES, the 8wl is turned off (Fig. 4, e). Put the sample hold circuit EIH into the hold state. That's all BB
The operation of C is incorrect, and the sensitivity adjustment of the analyzer is completed.

上の動作で連続スペクトル光の測光出力θD’に対する
吸光度変換器LOG2に対してのみθD−Vrとなるよ
うにフィードバック回路は構成されているが、ビームバ
ランス動作によって試料が供給されていないときのeH
が略eDと等しくなるように調整されるので、この場合
eHも亦略Vrとなっている。従ってVrを吸光度変換
部LOG1、LOG2夫々に対し直線性の最も良い範囲
にあるように選定しておくことにより、L OG 1゜
LOG2両方に対し最適の感度調整がなされることにな
る。なお、またこの実施例ではeDについてフィードバ
ックを行っているが、eHについてフィードバックを行
うように構成してもよい。
In the above operation, the feedback circuit is configured so that θD-Vr is obtained only for the absorbance converter LOG2 for the photometric output θD' of continuous spectrum light, but eH when no sample is supplied due to the beam balance operation
is adjusted so that it is approximately equal to eD, so in this case eH is also approximately equal to Vr. Therefore, by selecting Vr to be in the range with the best linearity for each of the absorbance converters LOG1 and LOG2, optimal sensitivity adjustment can be made for both LOG1°LOG2. Furthermore, in this embodiment, feedback is provided regarding eD, but it may be configured to provide feedback regarding eH.

なお引算器5UB2はeDLとeDLoとの差奪求めて
表示部M+に表示:するもので、θDLOはeD=Vr
のときの1.OG2の出力であり、調整動作完了によっ
てMlの表示はOになる。
The subtractor 5UB2 calculates the difference between eDL and eDLo and displays it on the display section M+, and θDLO is eD=Vr.
1. This is the output of OG2, and the display of Ml becomes O upon completion of the adjustment operation.

本発明装置は上述したような構成で、スイッチのオンオ
フと云う単一操作だけでかつ表示を目視しながら操作す
る必要もなく、きわめて簡単に分光光度計の感度調整が
でき、オペレータの負担軽減1分析作業の能率化が可能
となる。
The device of the present invention has the above-mentioned configuration, and the sensitivity of the spectrophotometer can be adjusted extremely easily with only a single operation of turning on and off the switch, and there is no need to operate while visually checking the display, reducing the burden on the operator. It becomes possible to streamline analysis work.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は従来例のブロック図、第2図は本発明の一実施
例装置のブロック図、第3図は本発明の他の一実施例装
置のブロック図、第4図は第3図の装置の動作を示すフ
ローチャートである。 FM・・・光検出器、LOG・・・吸光度変換器、M・
・・表示部、EA・・・誤差増幅器、SH・・・サンプ
ルホールド回路、Swl・・・サンプリングスイッチ、
DD、、。 直流−直流変換器、HCL・・・輝線スペクトル光源、
ATM・・・試料原子化部、MC・・・分光器、D・・
・連続スペクトル光源、BBC・・・ビームバランス制
御部、5UBI、5UB2・・・引算器。 代理人 弁理士  孫   浩  介
FIG. 1 is a block diagram of a conventional example, FIG. 2 is a block diagram of a device according to an embodiment of the present invention, FIG. 3 is a block diagram of another embodiment of the device according to the present invention, and FIG. 3 is a flowchart showing the operation of the device. FM...photodetector, LOG...absorbance converter, M.
...Display section, EA...Error amplifier, SH...Sample and hold circuit, Swl...Sampling switch,
DD... DC-DC converter, HCL... bright line spectrum light source,
ATM...Sample atomization section, MC...Spectrometer, D...
- Continuous spectrum light source, BBC...Beam balance control unit, 5UBI, 5UB2...Subtractor. Agent Patent Attorney Kosuke Son

Claims (1)

【特許請求の範囲】[Claims] 測光出力を基準値と比較する誤差増幅器と、サンプリン
グスイッチを介して上記誤差増幅器の出力が入力される
サンプルホールド回路とによってフィードバック回路が
構成され利得制御がなされ、上記サンプリングスイッチ
をオフとした場合、上記サンプルホールド回路の記憶信
号によシ感度が制御されるようにした測光系を備えた分
光分析装置。
A feedback circuit is configured by an error amplifier that compares the photometric output with a reference value and a sample hold circuit into which the output of the error amplifier is input via a sampling switch, and gain control is performed. When the sampling switch is turned off, A spectroscopic analyzer equipped with a photometric system whose sensitivity is controlled by the memory signal of the sample hold circuit.
JP19324081A 1981-11-30 1981-11-30 Spectroscopic analyzer Granted JPS5892931A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP19324081A JPS5892931A (en) 1981-11-30 1981-11-30 Spectroscopic analyzer

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP19324081A JPS5892931A (en) 1981-11-30 1981-11-30 Spectroscopic analyzer

Publications (2)

Publication Number Publication Date
JPS5892931A true JPS5892931A (en) 1983-06-02
JPS6246822B2 JPS6246822B2 (en) 1987-10-05

Family

ID=16304656

Family Applications (1)

Application Number Title Priority Date Filing Date
JP19324081A Granted JPS5892931A (en) 1981-11-30 1981-11-30 Spectroscopic analyzer

Country Status (1)

Country Link
JP (1) JPS5892931A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4726679A (en) * 1986-03-03 1988-02-23 The Perkin-Elmer Corporation Flame atomic absorption spectrophtometer including apparatus and method for logarithmic conversion

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5443492A (en) * 1977-08-17 1979-04-06 Westinghouse Electric Corp Electroacoustic transducer

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5443492A (en) * 1977-08-17 1979-04-06 Westinghouse Electric Corp Electroacoustic transducer

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4726679A (en) * 1986-03-03 1988-02-23 The Perkin-Elmer Corporation Flame atomic absorption spectrophtometer including apparatus and method for logarithmic conversion

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JPS6246822B2 (en) 1987-10-05

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