• 제목/요약/키워드: refining methods

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The bibliographical study on drug-processing about Pyritum (자연동(自然銅)의 수치법(修治法)에 대한 문헌적(文獻的) 고찰(考察))

  • Min, Pyoung-gee;Seo, Young-bae
    • Journal of Haehwa Medicine
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    • v.10 no.1
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    • pp.47-53
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    • 2001
  • In the result of investigating traditional chinese medical literatures to understand drug-processing about Pyritum, we could reach conclusions as follows: 1. Pyritum are divided into fresh Pyritum, calcining Pyritum, tempered Pyritum with vinegar by methods of drug-processing. 2. The methods of drug-procession about Pyritum like calcination, quenching, refining drugs with water or medicinal broth of Glycyrrhizae Radix(licorice), boiling with medicinal broth of Glycyrrhizae Radix(licorice) were used complicately. 3. Calcining Pyritum are grinded easily, convenient to apply a pill and powder and As, S are easily removed. Quenching Pyritum act on liver channel and then are reinforced the effects of relieving blood stasis, Pain and gushed out effecive ingredients. Refining Pyritum with water are reinforced the effect of tranquilizing the mind and clearing heat. above results indicates that using calcination, quenching and refining drugs with water together is the best method of drug-processing about Pyritum.

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A Comparison on the Characteristics of Benzene Exposure between the Coal chemical and Petrochemical refining method during Turnaround (석유 및 석탄화학의 대보수작업중 벤젠노출 특성 비교)

  • Chung, Eun-Kyo;Yu, Gye-Muk;Shin, Jung-Ah;Kwon, Ji-Woon;Park, Hyun-Hee;Chung, Kwang-Jae;Lee, Jong-Han;Lee, In-Seop;Kang, Seong-Kyu;Ryu, Hyang-Woo;Kim, Young-Sun;Lee, Byung-Kyu;Jang, Jae-Kil;Kim, Won;Kim, Jung-Man
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.20 no.3
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    • pp.147-155
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    • 2010
  • This study was conducted to investigate the benzene exposure levels in coal chemical and petrochemical refining industries during BTX turnaround (TA) processes where benzene was being produced. Three companies producing benzene were selected, one coal chemical and two petrochemical industries. TA processes were classified into three stages: shut down, maintenance, and start up. Data was analyzed by classifying the refining method into 2 groups (Petrochemistry, Coal chemistry) for 823 workers. Comparing the data from petrochemical industries with data from a coal chemical refining industry, while benzene concentration levels of long-term samples during TA were not statistically different (p> 0.05), those levels of short-term samples were significantly different (p< 0.001). About 4.79 % of data in petrochemical industries exceed the occupational exposure limits (OELs) of benzene, 1 ppm. In a coal refining methods, about 15.7% exceeded the benzene OELs. The benzene concentrations in maintenance and start up stage of TA for petrochemical refineries were higher than those in a coal chemical refinery (p <0.01). These findings suggest that the coal chemical refining site requires more stringent work practice controls compare to petrochemical refining sites during TA processes. Personal protective equipments including organic respirators should be used by TA workers to protect them from benzene overexposure.

Impacts of label quality on performance of steel fatigue crack recognition using deep learning-based image segmentation

  • Hsu, Shun-Hsiang;Chang, Ting-Wei;Chang, Chia-Ming
    • Smart Structures and Systems
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    • v.29 no.1
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    • pp.207-220
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    • 2022
  • Structural health monitoring (SHM) plays a vital role in the maintenance and operation of constructions. In recent years, autonomous inspection has received considerable attention because conventional monitoring methods are inefficient and expensive to some extent. To develop autonomous inspection, a potential approach of crack identification is needed to locate defects. Therefore, this study exploits two deep learning-based segmentation models, DeepLabv3+ and Mask R-CNN, for crack segmentation because these two segmentation models can outperform other similar models on public datasets. Additionally, impacts of label quality on model performance are explored to obtain an empirical guideline on the preparation of image datasets. The influence of image cropping and label refining are also investigated, and different strategies are applied to the dataset, resulting in six alternated datasets. By conducting experiments with these datasets, the highest mean Intersection-over-Union (mIoU), 75%, is achieved by Mask R-CNN. The rise in the percentage of annotations by image cropping improves model performance while the label refining has opposite effects on the two models. As the label refining results in fewer error annotations of cracks, this modification enhances the performance of DeepLabv3+. Instead, the performance of Mask R-CNN decreases because fragmented annotations may mistake an instance as multiple instances. To sum up, both DeepLabv3+ and Mask R-CNN are capable of crack identification, and an empirical guideline on the data preparation is presented to strengthen identification successfulness via image cropping and label refining.

Removal of Pesticide Residues in Rice Bran Oil by Refining Process (미강유의 정제과정중 잔류농약의 감소)

  • 이철원;신효선
    • Journal of Food Hygiene and Safety
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    • v.11 no.2
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    • pp.89-97
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    • 1996
  • This study was carried out to determine the pesticide residues in rice bran, crude rice bran oil and the oil of various stages of refining process. Each samples were analyzed for 41 pesticide residues by multiclass multiresidue methods with GC-ECD, NPD and identified by GC-MSD. Rice bran were detected cypermethrin, diazinon, dichlofluanid, and its level were ranged from 0.01~0.122 ppm. Crude rice bran oil were detected cypermethrin, diazinon, dichlofluanid, dimethoate, etrimfos, flucythrinate, and its level were ranged from 0.015~0.654 ppm Crude rice bran oil has the higher level of pesticide residues and more varieties of pesticides than rice bran. But pesticide residues in the crude rice bran oil was found to be almost removed then pigment was decolorized by absorption using active carbon and clealy removed by thermolysis for deodorization.

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A Comparison on the Effect of Stabilization Methods for Rice Paddies contaminated by Heavy Metal (중금속 오염 농경지 토양의 안정화 처리공법 효과 비교)

  • Yu, Chan;Yun, Sung-Wook;Park, Jin-Chul;Lee, Jung-Hoon;Choi, Seung-Jin;Choi, Duck-Yong;Yi, Ji-Min
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.03a
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    • pp.819-835
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    • 2009
  • In order to investigate the field application of selected stabilization methods(cover soil method, surface and total interval treatment of embankment method) on rice paddies contaminated by heavy metals, column test was carried out with heavy metal-contaminated soils collected from rice paddies around abandoned mine site. Columns were made by acrylic and filled with untreated soil, treated soil mixed with amendments(lime stone and steel refining slag) and uncontaminated cover soil according to the design report. Distilled water was discharged into the columns with the velocity of 1 pore volume/day. During test, pH, EC, and heavy metal concentration were measured in the regular term. The column test result showed that the selected stabilization methods were effective remediation method to stabilize heavy metals in paddy soils, but it was also expected that application of surface treatment methods was required the careful observation on pH variation due to the lowest increment.

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Testing for Competition in the Korean Petroleum Refining Industry (유가자유화에 따른 국내 정유산업의 경쟁도 분석 -구조적 모형과 비구조적 모형의 비교-)

  • Oh, Sunah;Heo, Eunnyeong
    • Environmental and Resource Economics Review
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    • v.15 no.1
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    • pp.51-69
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    • 2006
  • This paper analyze the degree of competitiveness of the refining industry after price liberalization. We use two well-known methods: the first is Bresnahan (1982) and Lau (1982) method that estimates a structural model consisting of a demand relation and supply relation and the second is Panzar and Rosse (1987) method that estimates non structural model of the sum of elasticities of gross revenue with respect to input prices. Results from two models show mixed sign, however, our results indicate that price liberalization improved the degree of competitiveness.

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Changes of Corrective Astigmatism Values Depending on Position of Circle of Least Confusion in Astigmatic Refining Test Using Cross Cylinder (크로스실린더를 이용한 난시정밀검사에서 검사 전 최소착란원 위치에 따른 난시교정값의 변화)

  • Kim, Sang-Yeob;Lee, Min Jae;Lee, Kang Cheon;Lee, Tae Hui;Moon, Byeong-Yeon;Cho, Hyun Gug
    • Journal of Korean Ophthalmic Optics Society
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    • v.20 no.3
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    • pp.349-354
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    • 2015
  • Purpose: To investigate the changes of corrective values of astigmatism caused by the position of circle of least confusion on retina in refining astigmatic test using cross cylinder. Methods: 62 subjects (115 eyes) aged $22.24{\pm}2.48$ years participated for this study. After astigmatic test using a radial chart, refining test was performed using a cross cylinder in a condition of maximum plus to maximum visual acuity (MPMVA). Astigmatic refining test was repeatedly performed in each condition of which S+0.75 D, S+0.50 D, S+0.25 D, S-0.25 D, S-0.50 D, and S-0.75 D are added to spherical lenses of MPMVA. The measured values were compared with the values in MPMVA condition. Results: As compared with values in condition of MPMVA, change of astigmatic axis was increased with add the power of (+) spherical lenses and (-) spherical lenses. In same spherical condition, change of astigmatic axis was decreased with increment of astigmatic power (p<0.05). The corrective power of astigmatism was reduced with increment of (+) spherical lenses (p<0.05), and was raised with increment of (-) spherical lenses compared with the power in MPMVA condition. In case of adding (+) spherical lenses, difference of astigmatic power increased with increment of corrective astigmatism power in same test condition. Conclusions: In order to obtain a proper values for corrective astigmatism, position of circle of least confusion should be accurately adjusted before the performing an astigmatism's refining test.

Design of a miniature electron beam irradiation apparatus for domain refining grain oriented electrical steel with electron beams (전자빔 조사에 의한 방향성 전기강판의 철손 감소를 위한 소형 전자빔 조사장치 설계)

  • 조경재
    • Proceedings of the KIPE Conference
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    • 2000.07a
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    • pp.18-21
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    • 2000
  • A nonconstact technique for reducing the core loss of a grain oriented silicon steel has been developed by the use of mechanical scribing Q-switched laser plasma jet or electron beam irradiation. Among these methods electron beam irradiation has advantages of domain refining without any deformation or damage of insulating film on the surface of a grain criented Si-Fe. Over the past years this processing was performed in vaccum of 10-4 Torr or below causing the problem of high cost and difficulty of continuous works. In this paper a miniature electron permeable window through which electron beam energy 4-80keV and average current 0.1-2mA. were obtained for electron beam irradiating on air was designed and manufactured.

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Improved Kerosene Quality with the Use of a Gamma Alumina Nanoparticles Supported Zinc Oxide Catalyst in a Digital Batch Baffled Reactor: Experiments and Process Modelling

  • Jasim I. Humadi;Ghassan Hassan Abdul Razzaq;Ghassan Hassan Abdul Razzaq;Mustafa A. Ahmed;Liqaa I. Saeed
    • Korean Chemical Engineering Research
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    • v.61 no.2
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    • pp.226-233
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    • 2023
  • To create an environmentally sustainable fuel with a low sulfur concentration, requires alternative sulfur removal methods. During the course of this study, a high surface gamma alumina-supported ZnO nanocatalyst with a ZnO/-Al2O3 ratio of 12% was developed and tested for its ability to improve the activity of the oxidative desulfurization (ODS) process for the desulfurization of kerosene fuel. Scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) were used to characterize the produced nanocatalyst. In a digital batch baffled reactor (20~80 min), the effectiveness of the synthesized nanocatalyst was tested at different initial concentrations of dibenzothiophene (DBT) of 300~600 ppm, oxidation temperatures (25~70 ℃), and oxidation periods (0.5, 1, and 2 hours). The baffles included in the digital baffled batch reactor resist the swirling of the reaction mixture, thus facilitating mixing. The ODS procedure yielded the maximum DBT conversion (95.5%) at 70 ℃ with an 80-minute reaction time and an initial DBT level of 600 ppm. The most precise values of kinetic variables were subsequently determined using a mathematical modelling procedure for the ODS procedure. The average absolute error of the simulation findings was less than 5%, demonstrating a good degree of agreement with the experimental results acquired from all runs. The optimization of the operating conditions revealed that 99.1% of the DBT can be removed in 140 minutes.