• Korean Journal of Environmental Agriculture
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• v.13 no.2
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• pp.199-208
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• 1994

Analytical methods for the determination of the derivatives of the herbicide (${\pm}$)-2-(4-chloro-2-methylphenoxy)propionic acid (MCPP) by capillary column gas chromatography with mass spectrometer (GC-MS) and electron-capture detection (GC-ECD) were studied. A successful procedure was introduced for the ester preparation using $H_2SO_4$, as the catalyst and the alcohol 2,2,2-trichloroethanol (TCE) or 2,2,2-trifluoroethanol (TFE). The identificaiton and elucidation of MCPP by GC-MS spectrometry following the esterification with diazomethane, $BF_3$/methanol, $H_2SO_4$/methanol, TCE, TFE, or pentafluorobenzyl bromide (PFB) were carried out. A comparison of the response-sensitivities among those MCPP esters was made with GC-ECD. Although the methylation product of MCPP was confirmed by GC-MS, its low sensitivity to the ECD limited the detection of MCPP. TCE, TFE, and PFB derivatization methods resulted in a high rate of MCPP esterifications and very sensitive ECD molecular responses. Based on efficiency, convenience, worker safety, and least sample contamination, TFE esterificaiton was considered as the superior method for MCPP analysis to the other methods of derivatization. An accurate method is described for quantifying MCPP in soil leachates by GC-ECD at very low concentrations without the requirement of a complicated clean-up process. As a result, MCPP residues at concentrations of less than $0.1{\mu}g$ in 100ml soil leachate were detected.

• Korean Journal of Microbiology
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• v.30 no.2
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• pp.96-100
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• 1992

The microbiological degradation of 2-(2-methyl-4-chloro-phenoxy) propionic acid (MCPP) was evaluated using mixed cultures of soil bacteria. The mixed cultures comprised Pseudomonas species, Flavobacterium species, and Achromobacter species. The bacteria used MCPP as the sole source of carbon and energy but only a partial degradation of the parent compound occurred MCPP degradation proceeded via the formation of 2-methyl-4-chlorophenol (2, 4-MCP) which was detected by high pressure liquid chromatography (PHLC) and confirmed by gas chromatography-mass sepctrometry. This intermediate occurred only transiently and no evidence was seen for the presence of other intermediates detectable by the reverse-phase HPLC or UV absorbance.

• The Microorganisms and Industry
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• v.18 no.1
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• pp.2-8
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• 1992

The present study was undertaken to characterize the biodegradation of phenoxy herbicides, 2,4-D and MCPP, under aerobic conditions. Specifically, the work had the following objectives; i) to develop and characterize bacterial mixed cultures for the 2,4-D and MCPP degradation, ii) to evaluate the degradation of 2,4-D and MCPP in shake-flasks and stirred tank reactors; and iii) to evaluate the treatment of industrial fertilizer solid wste material containing 2,4-D and MCPP.

• Journal of Environmental Health Sciences
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• v.23 no.3
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• pp.72-79
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• 1997

본 실험은 제초제인 2,4-D, dicamba, 및 MCPP의 토양에서의 이동을 확인하고 평가하기 위하여 토양종류에 따른 이들 제초제의 흡착과 휘발을 일정시간 동안 조사하였다. 제초제의 토양중 흡착은 batch isotherm으로 조사하였는데, MCPP와 2,4-D는 Freundlich식에서 직선으로 나타났으며, dicamba는 곡선으로 나타났다. Silty clay 토양에서 MCPP의 K$_d$ 및 K$_{fr}$값이 가장 높았으며, loamy sand 토양에서는 dicamba의 K$_d$, K$_{fr}$값이 가장 낮았다. 전반적으로 silty clay 토양에서 K$_d$, K$_{fr}$값이 높았고 N값은 낮았다. 토양에 살포된 제초제의 약 40%가 처리 25일 경과시 휘발되거나 분해되었으며, 이들 제초제중 2,4-D가 dicamba와 MCPP에 비하여 분해 및 휘발속도가 빨랐다. 모든 토양에서 이들 제초제의 분해 및 휘발속도는 공기에 노출된 초기에 현저하게 빠른 것으로 나타나고 있다. 본 연구의 결과는 자연환경중에서 이들 제초제의 이동 및 잔류 현황을 예견하는데 사용될 수 있을 것으로 사료된다.

• Journal of The Korean Society of Clinical Toxicology
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• v.3 no.1
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• pp.45-47
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• 2005

MCPP (2-(2-methyl-4-chlorophenoxy)propionic acid; mecoprop), a hormonal weedkiller has been widely used. Although chronic exposure is generally considered to be mildly toxic to man, acute intoxication can be severe and should thus be taken seriously. We report the case of a patient who died after ingestion of MCPP. A 64-year-old man ingested about 400 ml of $50\%$ MCPP solution. He was stuporous and had an inadequate respiration. He had an hypotension which did not respond to vasopressors and died about twelve hours after ingestion.

• Korean Journal of Environmental Agriculture
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• v.2 no.2
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• pp.59-64
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• 1983

A study was undertaken to investigate the persistence of 2,4-D and MCPP in two different Suweon soils under field conditions. MCPP was extracted from soil with aqueous calcium hydroxide solution and then derivatized to pentafluorobenzyl ester to enhance the electron capture sensitivity. Total recovery of MCPP from soil was 85.6% and the detection limit for 20g sample was 0.02 ppm. Ethyl ester of 2,4-D applied to soil was rapidly hydrolysed to 2,4-D with the half-life of less than 1 day. Half-life of total 2,4-D ethyl ester, including 2,4-D, incorporated into soils at a rate of 0.045 ㎏ a.i./10a was $4{\sim}7$ days and that of under laboratory conditions was $7{\sim}8$ days. Half-life of MCPP applied at a rate of 0.25㎏ a.i./10a under field conditions was $9{\sim}12$ days and that of under laboratory conditions was $12{\sim}23$ days.

• The Journal of Information Systems
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• v.17 no.3
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• pp.39-58
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• 2008

Mixed Chinese Postman Problem (MCPP) is a practical generalization of the classical Chinese Postman Problem (CPP) and it could be applied in many real world. Although MCPP is useful in terms of reality, MCPP has been proved to be a NP-complete problem. To find optimal solutions efficiently in MCPP, we can reduce searching space to be small effective searching space containing optimal solutions. We propose GENIIS methodology, which is a kind of hybrid algorithm combines the approximate algorithms and genetic algorithm. To get good solutions in the effective searching space, GENIIS uses approximate algorithm and genetic algorithm. This paper validates the usefulness of the proposed approach in a simulation. The results of our paper could be utilized to increase the efficiencies of network and transportation in business.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.4
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• pp.389-394
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• 2011

This experiment was carried out to find effective weed control method of henbit deadnettle ($Lamium$ $amplexicaule$ L.) on cultivating field of Italian ryegrass ($Lolium$ $multiflorum$ Lam) using herbicide in Grassland and Forages Division, National Institute of Animal Science, RDA, Cheonan from 2008 to 2009. When Onehof was treated two times of spray, weed control ratio was most high as 90%, but this method can not be used because of much damage to Italian ryegrass. When MCPP was treated two times of spray, weed control ratio was high as 82%, and damage to Italian ryegrass was very insignificant. Especially, when the spray of MCPP was treated two times, dry matter yield of Italian ryegrass was 11,427 kg/ha, but that of non treatment was 1,658 kg/ha. That is to say, forage harvest was impossible in non treatment field. According to these results, to control henbit deadnettle on cultivating field of Italian ryegrass using herbicide, you need to treat with two times of spray of MCPP in mid-March. If you do, you can get regular harvest as much as 11,427 kg/ha.

• Journal of Animal Science and Technology
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• v.45 no.5
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• pp.865-874
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• 2003

Red sorrel, as one of exotic weeds in Korea, was introduced along with imported cereals for concentrate feed or within the seed for forage production. The plant was dominated in grassland and reduced the quality of forage. In particular, this weed cause severe problem in alpine grassland. This study was carried out to investigate the effect and response of red sorrel and forage crops by foliar and soil applied herbicide application. Mecoprop(MCPP) and pendimethaline were selected by pre-field experiment trials and applied to control the red sorrel in grassland. Herbicidal activity of MCPP was 77.2% at 500$m\ell$/10a level and 82.8% at 750$m\ell$/10a level. However, seeds of red sorrel from bare land formed after foliar applied herbicide treatment were germinated and covered bare land. Pendimethalin was not reduced the rhizome growth grown from red sorrel root but retarded seedling growth of germinated red sorrel. The herbicidal activity of pendimethalin to the red sorrel seedling was 83.0%. 2 times application of MCPP at the rate of 750$m\ell$/10a was effective to control of red sorrel regrown from root and herbicidal activity was 93.2%. MCPP and pendimethaline treatment was not reduced growth of grass and have no herbicidal injury to forage crop seedling. Amount of MCPP and pendimethalin remained in grass plant was decreased from 20 days after herbicide treatment and could not be problem in livestock feeding.

• The korean journal of orthodontics
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• v.48 no.4
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• pp.224-235
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• 2018

Objective: The purpose of this study was to compare the skeletal, dental, and soft-tissue treatment effects of nonextraction therapy using the modified C-palatal plate (MCPP) to those of premolar extraction (PE) treatment in adult patients with Class II malocclusion. Methods: Pretreatment and posttreatment lateral cephalographs of 40 adult patients with Class II malocclusion were retrospectively analyzed. The MCPP group comprised 20 patients treated with total arch distalization of the maxillary arch while the PE group comprised 20 patients treated with four PE. Fifty-eight linear and angular measurements were analyzed to assess the changes before and after treatment. Descriptive statistics, paired t-test, and multivariate analysis of variance were performed to evaluate the treatment effects within and between the two groups. Results: The MCPP group presented 3.4 mm of retraction, 1.0 mm of extrusion, and $7.3^{\circ}$ lingual inclination of the maxillary central incisor. In comparison, the PE group displayed greater amount of maxillary central incisor retraction and retroclination, mandibular incisor retraction, and upper lip retraction (5.3 mm, $14.8^{\circ}$, 5.1 mm, and 2.0 mm, respectively; p < 0.001 for all). In addition, the MCPP group showed 4.0 mm of distalization and 1.3 mm of intrusion with $2.9^{\circ}$ distal tipping of the maxillary first molars. Conclusions: These findings suggest the MCPP is an effective distalization appliance in the maxillary arch. The amount of incisor retraction, however, was significantly higher in the PE group. Therefore, four PE may be recommended when greater improvement of incisor position and soft-tissue profile is required.