KR20010017300A - A method for determinating concentrations of dissolved oxygen by using spectrophotometry method - Google Patents
A method for determinating concentrations of dissolved oxygen by using spectrophotometry method Download PDFInfo
- Publication number
- KR20010017300A KR20010017300A KR1019990032747A KR19990032747A KR20010017300A KR 20010017300 A KR20010017300 A KR 20010017300A KR 1019990032747 A KR1019990032747 A KR 1019990032747A KR 19990032747 A KR19990032747 A KR 19990032747A KR 20010017300 A KR20010017300 A KR 20010017300A
- Authority
- KR
- South Korea
- Prior art keywords
- dissolved oxygen
- oxygen concentration
- sample
- iodine
- absorbance
- 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.)
- Withdrawn
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N31/00—Investigating or analysing non-biological materials by the use of the chemical methods specified in the subgroup; Apparatus specially adapted for such methods
- G01N31/16—Investigating or analysing non-biological materials by the use of the chemical methods specified in the subgroup; Apparatus specially adapted for such methods using titration
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/18—Water
- G01N33/1806—Biological oxygen demand [BOD] or chemical oxygen demand [COD]
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Immunology (AREA)
- General Physics & Mathematics (AREA)
- Pathology (AREA)
- General Health & Medical Sciences (AREA)
- Biochemistry (AREA)
- Analytical Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Molecular Biology (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Biodiversity & Conservation Biology (AREA)
- Medicinal Chemistry (AREA)
- Food Science & Technology (AREA)
- Biomedical Technology (AREA)
- Emergency Medicine (AREA)
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
- Investigating Or Analysing Materials By The Use Of Chemical Reactions (AREA)
Abstract
본 발명은 분광법을 이용하여 수중 용존 산소 농도를 측정하는 방법에 관한 것으로,The present invention relates to a method for measuring the dissolved oxygen concentration in water using spectroscopy,
(a)수질 시료에 염화망간 또는 황산망간 및 알칼리 요오드화나트륨 용액을 첨가하여 망간 이온을 염기 용액하에 수산화제일망간으로 침전시키는 단계;(a) adding manganese chloride or manganese sulfate and an alkali sodium iodide solution to the water sample to precipitate manganese ions into manganese hydroxide under a base solution;
(b)상기 수산화제일망간을 상기 시료내 용존 산소에 의해 수산화제이망간으로 산화시키는 단계;(b) oxidizing the monomanganese hydroxide to dimanganese hydroxide by dissolved oxygen in the sample;
(c)상기 수산화제이망간을 산에 의해 용해시키고, 요오드 이온에 의해 환원시킴으로써 용존 산소 농도에 대응되는 요오드를 유리시키는 단계; 및(c) dissolving the manganese hydroxide with acid and reducing with iodine ions to release iodine corresponding to the dissolved oxygen concentration; And
(d)유리된 요오드를 티오황산나트륨으로 적정함으로써 용존 산소 농도를 측정하는 단계; 로 이루어지는 윙클러 적정법을 통해 수중 용존산소 농도를 측정함에 있어서,(d) determining the dissolved oxygen concentration by titrating the liberated iodine with sodium thiosulfate; In measuring the dissolved oxygen concentration in water through the Winkler titration method,
상기 단계(c)에서 유리된 요오드에 의해 시료중에 나타나는 색도의 최대 흡광 파장을 찾아내는 단계;Finding a maximum absorption wavelength of chromaticity appearing in the sample by the iodine liberated in step (c);
상기 흡광 파장에서 미리 용존산소 농도를 적절히 조절한 시료들에 대하여 흡광도와 용존 산소 농도와의 검량선을 작성하는 단계;Preparing a calibration curve between absorbance and dissolved oxygen concentration for samples in which the dissolved oxygen concentration is appropriately adjusted at the absorption wavelength in advance;
상기 흡광 파장에서 용존 산소 농도를 측정하고자 하는 시료의 흡광도를 측정하는 단계; 및Measuring the absorbance of the sample to be measured for dissolved oxygen concentration at the absorption wavelength; And
상기 시료의 흡광도를 검량선으로부터 용존 산소 농도로 정량하는 단계;로 이루어지는 수중 용존 산소 농도 측정 방법이 제공된다.There is provided a method for measuring dissolved oxygen concentration in water, comprising: quantifying the absorbance of the sample by the dissolved oxygen concentration from the calibration curve.
본 발명에 의하면, 티오황산나트륨에 의해 적정하여 결정하던 용존 산소의 양을 흡광법을 이용하여 결정함으로써 적정에 소요되는 시간과 노력을 대폭 줄이면서도 정확도를 그대로 유지하고, 정밀도를 향상시키면서 현장에서 간편하게 용존산소농도를 측정할 수 있다.According to the present invention, the amount of dissolved oxygen determined by titration with sodium thiosulfate is determined by using an absorption method, which greatly reduces the time and effort required for titration, while maintaining the accuracy as it is, while easily dissolving in the field while improving accuracy. Oxygen concentration can be measured.
Description
본 발명은 분광법을 이용하여 수중 용존 산소 농도를 측정하는 방법에 관한 것으로, 보다 상세하게는 수질 분석에서 용존산소 측정에 널리 쓰이는 윙클러 적정법(Winkler Method)에서 산소량 결정에 사용되어오던 티오황산나트륨(S2O3 2-) 적정법 대신 분광학적 방법을 사용함으로써 적정 오차 및 분석 시간을 대폭 저감시키면서 수중 용존 산소의 농도를 측정하는 방법에 관한 것이다.The present invention relates to a method for measuring dissolved oxygen concentration in water using spectroscopy, and more specifically, sodium thiosulfate (S 2 ), which has been used to determine the amount of oxygen in the Winkler titration method widely used for measuring dissolved oxygen in water quality analysis. O 3 2- ) This method relates to a method for measuring the concentration of dissolved oxygen in water while drastically reducing titration error and analysis time by using spectroscopic method instead of titration method.
일반적으로 수질 환경에서 용존 산소를 측정하는 방법으로는 고전적으로 윙클러 적정법을 이용한다. 수중 용존 산소 농도 측정은 기본적으로 이 윙클러 적정법을 통해 얻어진 값을 기준으로 하며, 따라서 새로운 분석 방법 개발시에도 윙클러 적정법에 의한 농도값과의 비교를 통해 검증하는 것이 필수적이다.Generally, the Winkler titration method is used to measure dissolved oxygen in the water environment. Dissolved oxygen concentrations in water are basically based on the values obtained through this Winkler titration method, and therefore, it is essential to verify them by comparison with the Winkler titration method when developing new analytical methods.
이 윙클러 적정법의 측정 원리를 구체적으로 살펴보면 다음과 같다.The principle of measurement of this Winkler titration method is as follows.
수질 시료에 염화망간(또는 황산망간)과 알칼리 요오드화나트륨 용액을 첨가하면 망간 이온이 염기용액하에 수산화제일망간으로 침전되고, 시료내 용존산소에 의해 수산화제이망간으로 산화된다.When manganese chloride (or manganese sulfate) and an alkali sodium iodide solution are added to the water sample, manganese ions are precipitated into monomanganese hydroxide under a basic solution and oxidized to dimanganese hydroxide by dissolved oxygen in the sample.
상기 수산화제이망간은 다시 산에 의해 용해되고 요오드 이온에 의해 환원됨으로써 용존산소 농도에 대응되는 요오드가 유리되는데, 이때 유리된 요오드를 티오황산나트륨으로 적정하여 용존 산소 농도를 측정하게 된다.The manganese hydroxide is dissolved again by acid and reduced by iodine ions to release iodine corresponding to the dissolved oxygen concentration. At this time, the dissolved iodine is titrated with sodium thiosulfate to measure the dissolved oxygen concentration.
이를 화학식으로 나타내면 다음과 같다.This is represented by the following formula.
상기 윙클러 적정법의 경우에는 분석자에 따라 동일 시료에 대하여도 적정상의 오차가 발생할 수 있는등 정밀도 측면에서 시료 농도 7.00mgO2/L 수준에서 ±0.8mgO2/L정도로 최소 1.1이상의 오차가 발생하는 것으로 알려져 있다.The case of Winkler titration method has been known that the degree of at least 1.1, such as errors in the precision sample concentration side 7.00mgO 2 / L level in an error that may occur on the titration about ± 0.8mgO 2 / L for the same sample caused by the analyst have.
이밖에도 산화환원 전위차를 이용한 격막 전극법의 원리를 적용하여 용존 산소 농도를 직독으로 판독하는 DO 미터(DO meter)가 현장 분석용으로 널리 사용되는데, 이는 시료중의 용존 산소가 격막을 통과하여 전극의 표면에서 산화-환원 반응을 일으키고 이때 용존 산소의 농도에 비례하여 흐르는 전류량으로부터 용존 산소량을 측정하는 방법이다.In addition, a DO meter, which reads the dissolved oxygen concentration directly by applying the principle of the diaphragm electrode method using the redox potential difference, is widely used for field analysis. In this case, the amount of dissolved oxygen is measured from the amount of current flowing in proportion to the concentration of dissolved oxygen.
그러나 상기 격막 전극법의 경우는 현장에서 직독할 수 있는 장점이 있는 반면에, 현장에서 DO 미터로 용존 산소를 측정한 일부 시료의 경우에는 윙클러 적정법을 통해 검정하는 과정을 거쳐야 하는등 정확도나 정밀도 측면에서 다소 신뢰성이 떨어질 수 있다는 단점이 있다.However, in the case of the diaphragm electrode method, there is an advantage that can be directly read in the field, while in the case of some samples measured DO dissolved in the field by the Winkler titration method, such as the accuracy or precision in terms of accuracy The disadvantage is that it may be somewhat unreliable.
이에 본 발명의 목적은 윙클러 적정법에서의 정확도를 그대로 유지하면서 분석자에 따른 적정 오차에서 발생하는 정밀도의 저하를 막음과 동시에 격막 전극법에 의한 DO 미터가 갖는 현장에서의 직접 분석 장점을 유지시킬 수 있는 수중 용존 산소 측정 방법을 제공하려는데 있다.Accordingly, an object of the present invention is to prevent the deterioration of precision caused by the titration error according to the analyst while maintaining the accuracy in the Winkler titration method, and to maintain the advantages of direct analysis in the field of DO meter by the diaphragm electrode method. It is to provide a method for measuring dissolved oxygen.
도 1은 본 발명에서 사용하는 분광법을 이용하여 수중 용존산소를 측정하는 장치를 나타내는 사시도,1 is a perspective view showing an apparatus for measuring dissolved oxygen in water using the spectroscopy used in the present invention,
도 2는 윙클러 적정법에서 유리된 요오드에 의해 시료중에 나타나는 색도의 최대 흡광 파장을 나타내는 그래프,2 is a graph showing the maximum absorption wavelength of chromaticity represented in a sample by iodine liberated by Winkler titration;
도 3은 윙클러 적정법과 본 발명의 방법에 의해 측정한 용존 산소 농도간의 상관 관계를 나타내는 그래프이다.3 is a graph showing the correlation between the Winkler titration method and the dissolved oxygen concentration measured by the method of the present invention.
*도면의 주요 부위에 대한 간단한 부호의 설명** Description of simple symbols for the main parts of the drawings *
1... 흐름주입식(flow injection type) 흡광 광도계1. Flow injection type absorbance photometer
2... 시료 주입라인 3... 시료병2 ... Sample injection line 3 ... Sample bottle
4... 시료 받침판 5... 회전식 시료 지지판4 ... Sample Support Plate 5 ... Rotary Sample Support Plate
6... 용존산소 측정용 시료병 인입구6 ... Sample bottle inlet for dissolved oxygen measurement
본 발명에 의하면,According to the invention,
(a)수질 시료에 염화망간 또는 황산망간 및 알칼리 요오드화나트륨 용액을 첨가하여 망간 이온을 염기 용액하에 수산화제일망간으로 침전시키는 단계;(a) adding manganese chloride or manganese sulfate and an alkali sodium iodide solution to the water sample to precipitate manganese ions into manganese hydroxide under a base solution;
(b)상기 수산화제일망간을 상기 시료내 용존 산소에 의해 수산화제이망간으로 산화시키는 단계;(b) oxidizing the monomanganese hydroxide to dimanganese hydroxide by dissolved oxygen in the sample;
(c)상기 수산화제이망간을 산에 의해 용해시키고, 요오드 이온에 의해 환원시킴으로써 용존 산소 농도에 대응되는 요오드를 유리시키는 단계; 및(c) dissolving the manganese hydroxide with acid and reducing with iodine ions to release iodine corresponding to the dissolved oxygen concentration; And
(d)유리된 요오드를 티오황산나트륨으로 적정함으로써 용존 산소 농도를 측정하는 단계; 로 이루어지는 윙클러 적정법을 통해 수중 용존산소 농도를 측정함에 있어서,(d) determining the dissolved oxygen concentration by titrating the liberated iodine with sodium thiosulfate; In measuring the dissolved oxygen concentration in water through the Winkler titration method,
상기 단계(c)에서 유리된 요오드에 의해 시료중에 나타나는 색도의 최대 흡광 파장을 찾아내는 단계;Finding a maximum absorption wavelength of chromaticity appearing in the sample by the iodine liberated in step (c);
상기 흡광 파장에서 미리 용존산소 농도를 적절히 조절한 시료들에 대하여 흡광도와 용존 산소 농도와의 검량선을 작성하는 단계;Preparing a calibration curve between absorbance and dissolved oxygen concentration for samples in which the dissolved oxygen concentration is appropriately adjusted at the absorption wavelength in advance;
상기 흡광 파장에서 용존 산소 농도를 측정하고자 하는 시료의 흡광도를 측정하는 단계; 및Measuring the absorbance of the sample to be measured for dissolved oxygen concentration at the absorption wavelength; And
상기 시료의 흡광도를 검량선으로부터 용존 산소 농도로 정량하는 단계;로 이루어지는 수중 용존 산소 농도 측정 방법이 제공된다.There is provided a method for measuring dissolved oxygen concentration in water, comprising: quantifying the absorbance of the sample by the dissolved oxygen concentration from the calibration curve.
이하, 본 발명에 대하여 설명한다.EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated.
본 발명에서는 윙클러 적정법에서 용존 산소 농도에 대응하여 유리되는 요오드의 양에 따라 시료의 색도에 차이가 나는 점에 착안하여 기존의 티오황산나트륨으로 유리된 요오드를 적정하는 단계 대신에 시료중의 용존산소 농도차에 따라 유리된 요오드에 의해 나타나는 시료의 흡광도 차이를 용존 산소 정량에 응용하는 것이다.In the present invention, the concentration of dissolved oxygen in the sample instead of the step of titrating iodine liberated with conventional sodium thiosulfate by focusing on the difference in the chromaticity of the sample according to the amount of iodine released corresponding to the dissolved oxygen concentration in the Winkler titration method The difference in absorbance of the sample, represented by the iodine liberated by the difference, is applied to the determination of dissolved oxygen.
상기와 같은 본 발명의 기능 및 작용을 도면을 참조하여 설명하면 다음과 같다.Referring to the function and operation of the present invention as described above with reference to the drawings.
도 1에 나타낸 바와 같이, 본 발명에서는 흐름주입식(flow injection type) 흡광 광도계(1)를 사용하여 윙클러 적정법 과정에서 유리된 요오드가 들어있는 시료(3)를 시료 받침판(4)상에 회전식 시료 지지판(5)의 시료병 인입구(6)에 꽂아 넣고 연속적으로 시료 주입라인(2)를 통해 흡광 광도계내로 주입시켜 흡광도를 측정한다.As shown in FIG. 1, in the present invention, a sample (3) containing iodine liberated in a Winkler titration process using a flow injection type absorbance photometer (1) is rotated on a sample support plate (4). Insert into the sample bottle inlet 6 of (5) and continuously injected into the absorbance photometer through the sample injection line (2) to measure the absorbance.
차후 공정에서 용존 산소 농도를 적정하기 위한 시료의 흡광도 측정은 도 2에 나타낸 바와 같이 최대 흡광도를 보이는 파장에서 수행한다.The absorbance measurement of the sample for titrating the dissolved oxygen concentration in the subsequent process is performed at the wavelength showing the maximum absorbance as shown in FIG.
흡광도 측정을 통해 용존 산소 농도를 결정하기 위해서는 우선 용존 산소 농도를 적절히 조절한 시료에 대하여 각 시료에 대한 흡광도를 측정하고, 이들 흡광도와 용존 산소 농도와의 관계를 검량선으로 나타낸 다음, 이 검량선을 이용하여 분석하고자 하는 시료의 흡광도를 용존 산소 농도로 정량한다.In order to determine the dissolved oxygen concentration by measuring the absorbance, the absorbance of each sample is first measured for a sample in which the dissolved oxygen concentration is properly adjusted, and the relationship between the absorbance and the dissolved oxygen concentration is represented by a calibration curve, and then the calibration curve is used. The absorbance of the sample to be analyzed is quantified by the dissolved oxygen concentration.
이하, 실시예를 통하여 본 발명을 상세히 설명한다.Hereinafter, the present invention will be described in detail through examples.
〈실시예〉<Example>
하기 실시예는 나아가 본 발명의 다양한 견지를 예시하는 것으로, 본 발명의 범위를 이에 한정하는 것은 아니다.The following examples further illustrate various aspects of the invention and do not limit the scope thereof.
실시예 1Example 1
윙클러 적정법 과정에서 유리된 요오드가 들어있는 시료를 도 1에 나타낸 장치를 사용하여 처리하였는데, 이를 상세히 설명하면 다음과 같다.In the Winkler titration process, the sample containing free iodine was processed using the apparatus shown in FIG. 1, which will be described in detail as follows.
흐름주입식(flow injection type) 흡광 광도계(1)를 사용하여 윙클러 적정법 과정에서 유리된 요오드가 들어있는 시료(3)를 시료 받침판(4)상에 회전식 시료 지지판(5)의 시료병 인입구(6)에 꽂아 넣고 연속적으로 시료 주입라인(2)를 통해 흡광 광도계내로 주입시켜 흡광도를 측정하였다.Sample bottle inlet (6) of rotary sample support plate (5) on sample support plate (4) containing iodine liberated during Winkler titration using flow injection type absorbance photometer (1) Inserted into and continuously injected into the absorbance photometer through the sample injection line (2) to measure the absorbance.
차후 공정에서 용존 산소 농도를 적정하기 위한 시료의 흡광도 측정은 도 2에서 최대 흡광 파장으로 판독된 456nm에서 수행하였다. 그런 다음 검량선으로부터 동일한 시료에 대하여 용존산소 농도를 10회 정량하고 그 결과를 하기표 1에 나타내었다.Absorbance measurements of samples for titrating dissolved oxygen concentrations in subsequent processes were performed at 456 nm read at the maximum absorption wavelength in FIG. 2. Then, the dissolved oxygen concentration was quantified 10 times for the same sample from the calibration curve and the results are shown in Table 1 below.
상기표 1에서 보듯이, 윙클러 적정법에 의해 측정된 6.75mgO2/L 농도의 시료에서 ±0.01mgO2/L로 약0.15의 정밀도를 나타내므로, 상기한 바와 같이 종래 윙클러 적정법에서의 1.1보다 향상된 정밀도를 확인할 수 있었다.As shown in Table 1, the accuracy of about 0.15 mg / 0.01 mgO 2 / L in a sample of 6.75 mgO 2 / L concentration measured by the Winkler titration method, as described above, improved accuracy than 1.1 in the conventional Winkler titration method as described above Could be confirmed.
실시예 2Example 2
본 실시예는 본 발명에 의한 분광법과 종래의 윙클러 적정법간의 정확도 비교를 나타낸 것이다.This example shows the accuracy comparison between spectroscopy according to the present invention and conventional Winkler titration methods.
일반적으로 수중에서 나타날 수 있는 농도 1∼7ppm을 대상으로 실시한 윙클러 적정법과 본 발명에 의한 방법을 도시한 도 3을 비교해 보면, 서로 100의 직선 상관 관계를 보이고 있음을 확인할 수 있다.In general, comparing the Winkler titration method to the concentration of 1 to 7ppm that can appear in water and Figure 3 showing the method according to the present invention, it can be seen that there is a linear correlation of 100 with each other.
따라서 윙클러 적정법과 마찬가지로 본 발명에 의한 분광법이 정확도면에서 대등한 수준을 나타내고 있음을 알 수 있다.Therefore, like the Winkler titration method, it can be seen that the spectroscopy according to the present invention shows a level of accuracy comparable.
상기한 바에 따르면, 수중 용존산소 측정시 윙클러 적정법의 정확도를 그대로 유지하면서 정밀도를 향상시키고 또한 적정에 걸리는 시간과 노력을 대폭 줄일 수 있으며, 현장에서도 손쉽게 용존 산소 농도를 측정할 수 있다.According to the above, it is possible to improve the accuracy while maintaining the accuracy of the Winkler titration method while measuring the dissolved oxygen in water, and to significantly reduce the time and effort required for titration, and to easily measure the dissolved oxygen concentration in the field.
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019990032747A KR20010017300A (en) | 1999-08-10 | 1999-08-10 | A method for determinating concentrations of dissolved oxygen by using spectrophotometry method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019990032747A KR20010017300A (en) | 1999-08-10 | 1999-08-10 | A method for determinating concentrations of dissolved oxygen by using spectrophotometry method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| KR20010017300A true KR20010017300A (en) | 2001-03-05 |
Family
ID=19606695
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| KR1019990032747A Withdrawn KR20010017300A (en) | 1999-08-10 | 1999-08-10 | A method for determinating concentrations of dissolved oxygen by using spectrophotometry method |
Country Status (1)
| Country | Link |
|---|---|
| KR (1) | KR20010017300A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20020047082A (en) * | 2002-05-28 | 2002-06-21 | 전영관 | The method for analysis of Total organic carbon |
| KR100860545B1 (en) * | 2007-03-30 | 2008-09-26 | (주)백년기술 | Dissolved oxygen automatic measuring device and method |
| CN110672784A (en) * | 2019-10-29 | 2020-01-10 | 饶宾期 | Water body dissolved oxygen detection device based on machine vision |
| KR20240061816A (en) * | 2022-11-01 | 2024-05-08 | 주식회사 씨맥 | A Method for measuring dissolved oxygen concentration in water using spectroscopy |
-
1999
- 1999-08-10 KR KR1019990032747A patent/KR20010017300A/en not_active Withdrawn
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20020047082A (en) * | 2002-05-28 | 2002-06-21 | 전영관 | The method for analysis of Total organic carbon |
| KR100860545B1 (en) * | 2007-03-30 | 2008-09-26 | (주)백년기술 | Dissolved oxygen automatic measuring device and method |
| CN110672784A (en) * | 2019-10-29 | 2020-01-10 | 饶宾期 | Water body dissolved oxygen detection device based on machine vision |
| CN110672784B (en) * | 2019-10-29 | 2024-06-11 | 华星德安(河北)环保科技有限公司 | Water body dissolved oxygen detection device based on machine vision |
| KR20240061816A (en) * | 2022-11-01 | 2024-05-08 | 주식회사 씨맥 | A Method for measuring dissolved oxygen concentration in water using spectroscopy |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Sweetser et al. | Spectrophotometric titrations with ethylenediaminetetraacetic acid: determination of magnesium, calcium, zinc, cadmium, titanium, and zirconium | |
| EP2927683A1 (en) | Lithium measurement method | |
| JP4669286B2 (en) | A method for aligning the base point of the scale of a device that measures the amount of silicon dioxide by colorimetric determination with the standard | |
| Issopoulos | High-sensitivity spectrophotometric determination of trace amounts of levodopa, carbidopa and α-methyldopa | |
| KR20010017300A (en) | A method for determinating concentrations of dissolved oxygen by using spectrophotometry method | |
| US20210270794A1 (en) | Method of determining chemical oxygen demand (cod) for high chloride samples | |
| US9829474B2 (en) | Acetate complexes and methods for acetate quantification | |
| Seok et al. | A simple spectrophotometric determination of dissociation constants of organic compounds | |
| US9513227B2 (en) | Method for quantitative determination of oxidant and apparatus for quantitative determination of oxidant | |
| Karayannis | Comparative kinetic study for rate constant determination of the reaction of ascorbic acid with 2, 6-dichlorophenolindophenol | |
| Masadome | Determination of cationic polyelectrolytes using a photometric titration with crystal violet as a color indicator | |
| KR102790641B1 (en) | A Method for measuring dissolved oxygen concentration in water using spectroscopy | |
| Madrakian et al. | Simultaneous spectrophotometric determination of levodopa and carbidopa in pharmaceutical formulations and water samples by using mean centering of ratio spectra and H-point standard addition methods | |
| Kramer et al. | Determination of microquantities of iodine in water solution by amperometric titrations | |
| US4478943A (en) | Method for measuring silver ion concentration in a solution | |
| US11378566B2 (en) | Method for determining ammonium | |
| JP4299696B2 (en) | Method for measuring persulfate concentration | |
| Clark et al. | Spectrophotometric study of a direct determination of serum calcium | |
| Takahashi et al. | Hydrogen-deuterium exchange study of amino acids and proteins by 200-to 230-nm spectroscopy | |
| Bertrand et al. | Determination of serum methemalbumin by second-derivative spectroscopy | |
| US20210123869A1 (en) | Method for measuring ph of test water | |
| JPH04249748A (en) | Measuring method of constituent concentration of mixture of hydrogen peroxide and ammonia | |
| Patrick et al. | Spectrophotometric and potentiometric study of the acid—base equilibria of indophenols in aqueous media | |
| JP3200904B2 (en) | Quantitative analysis method of trace alkaline earth metals in salt water | |
| González-Portal et al. | Spectrophotometric study of bismuth with N-(2-acetamido) iminodiacetic acid (ADA): Determination of bismuth in pharmaceutical formulations |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PA0109 | Patent application |
St.27 status event code: A-0-1-A10-A12-nap-PA0109 |
|
| R18-X000 | Changes to party contact information recorded |
St.27 status event code: A-3-3-R10-R18-oth-X000 |
|
| PG1501 | Laying open of application |
St.27 status event code: A-1-1-Q10-Q12-nap-PG1501 |
|
| PN2301 | Change of applicant |
St.27 status event code: A-3-3-R10-R13-asn-PN2301 St.27 status event code: A-3-3-R10-R11-asn-PN2301 |
|
| R18-X000 | Changes to party contact information recorded |
St.27 status event code: A-3-3-R10-R18-oth-X000 |
|
| PN2301 | Change of applicant |
St.27 status event code: A-3-3-R10-R13-asn-PN2301 St.27 status event code: A-3-3-R10-R11-asn-PN2301 |
|
| R17-X000 | Change to representative recorded |
St.27 status event code: A-3-3-R10-R17-oth-X000 |
|
| R18-X000 | Changes to party contact information recorded |
St.27 status event code: A-3-3-R10-R18-oth-X000 |
|
| PC1203 | Withdrawal of no request for examination |
St.27 status event code: N-1-6-B10-B12-nap-PC1203 |
|
| WITN | Application deemed withdrawn, e.g. because no request for examination was filed or no examination fee was paid | ||
| PN2301 | Change of applicant |
St.27 status event code: A-3-3-R10-R13-asn-PN2301 St.27 status event code: A-3-3-R10-R11-asn-PN2301 |
|
| PN2301 | Change of applicant |
St.27 status event code: A-3-3-R10-R13-asn-PN2301 St.27 status event code: A-3-3-R10-R11-asn-PN2301 |
|
| R18-X000 | Changes to party contact information recorded |
St.27 status event code: A-3-3-R10-R18-oth-X000 |
|
| R18-X000 | Changes to party contact information recorded |
St.27 status event code: A-3-3-R10-R18-oth-X000 |
|
| P22-X000 | Classification modified |
St.27 status event code: A-2-2-P10-P22-nap-X000 |
|
| R18-X000 | Changes to party contact information recorded |
St.27 status event code: A-3-3-R10-R18-oth-X000 |
|
| R18-X000 | Changes to party contact information recorded |
St.27 status event code: A-3-3-R10-R18-oth-X000 |
|
| R18-X000 | Changes to party contact information recorded |
St.27 status event code: A-3-3-R10-R18-oth-X000 |
|
| R18-X000 | Changes to party contact information recorded |
St.27 status event code: A-3-3-R10-R18-oth-X000 |
|
| R18-X000 | Changes to party contact information recorded |
St.27 status event code: A-3-3-R10-R18-oth-X000 |
|
| R18-X000 | Changes to party contact information recorded |
St.27 status event code: A-3-3-R10-R18-oth-X000 |
|
| R18-X000 | Changes to party contact information recorded |
St.27 status event code: A-3-3-R10-R18-oth-X000 |
|
| R18-X000 | Changes to party contact information recorded |
St.27 status event code: A-3-3-R10-R18-oth-X000 |
|
| R18 | Changes to party contact information recorded |
Free format text: ST27 STATUS EVENT CODE: A-3-3-R10-R18-OTH-X000 (AS PROVIDED BY THE NATIONAL OFFICE) |
|
| R18-X000 | Changes to party contact information recorded |
St.27 status event code: A-3-3-R10-R18-oth-X000 |