• 제목/요약/키워드: residual time

Search Result 2,097, Processing Time 0.036 seconds

Studies on the Residue of Carbofuran (Carbofuran의 잔류(殘溜)에 관(關)한 연구(硏究))

  • Park, Y.D.;Keum, S.S.;Lee, K.S.;Hong, Y.C.
    • Applied Biological Chemistry
    • /
    • v.20 no.2
    • /
    • pp.236-241
    • /
    • 1977
  • Analytical method of carbofuran (2,3-dihydro-2, 2-dimethyl-7-benzofuranyl methyl carbamate) residues and its persistence in rice seeds, rice seedlings, rice plants and soils were studied by gas-liquid chromatographic analysis using electron capture detector. 1. The effective column material for clean-up is Florisil (5% $H_2O$)+Alumina (4% $H_2O$)+absorbent mixture with rinsing the first 300l of eluants to remove impurities in the column materials. 2. The method of applying an gelatin encapsulated carbofuran to the root zone of rice plant is the longest persistence in its residues. 3. By seed treatment, no carbofuran residues were detected in rice seeds and seedlings. 4. The amounts of carbofuran residues in rice seedlings is in proportion to the soaking time of rice seedlings in carbofuran solution rather than the concentration of the chemical. 5. Applying carbofuran by root zone has the higher and the loger residual effect than broadcast. 6. Persistence of carbofuran in the high clay content soil is longer than in the low clay content soil. 7. No carbofuran residue was detected in rough rice at havesting time.

  • PDF

Benzo(a)pyrene Reduction in Sesame Oil Using Microwaving Method (Microwaving을 이용한 참기름의 Benzo(a)pyrene 저감화)

  • Oh, Sung-Cheon
    • Journal of the Korean Applied Science and Technology
    • /
    • v.29 no.2
    • /
    • pp.323-329
    • /
    • 2012
  • Sesame oil has superior oxidation stability and unique roasting flavor. Accordingly, this has been used for edible oil as well as a seasoning material for a long time in Korea. But sesame oil is a simple pressed oil, unrefined. During manufacturing process of roasting-expression, benzo(a)pyrene[B(a)P] formed as a strong carcinogenic substance causes a social problem. Detection of B(a)P in sesame oil was due to residual content in raw-sesame seeds and formation in roasting-expressing process. Especially, maximal forming process was roasting. Accordingly, in this study applied the traditional roasting method by roaster and microwaving method as a new type. Best roasting time by microwaving was for 5~10 min, B(a)P content in sesame oil was 0.53~0.79 ${\mu}g/kg$. These B(a)P contents showed 1/2 level than direct roasting method by roaster. As a result, B(a)P contents in sesame oil appeared the difference of more than 2 times according to roasting condition of sesame seed. For minimizing of B(a)P content in sesame oil is demanded roasting of sesame by microwaving than direct roasting by roaster.

Effect of Inorganic Coagulants on the Performance of Electro-Chemical Treatment Process Treating Hospital Wastewater (병원폐수의 전기화학적 처리시 무기응집제 주입 효과에 관한 연구)

  • Jeong, Seung-Hyun;Jeong, Byung-Gon
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.33 no.10
    • /
    • pp.709-716
    • /
    • 2011
  • Effect of inorganic coagulants dosing on the performance of electro-chemical process was studied when treating hospital wastewater having low electrolyte concentration. It is thought that adding inorganic coagulants caused increase in concentration of electrolyte and this caused increase in free chloride concentration and consequently, caused increase in indirect oxidation effect. Thus, COD removal efficiencies more than doubled in percentage terms at the 2 hrs of reaction time and current density of $1.76A/dm^2$ compared with the results obtained from the parallel experiments without adding inorganic coagulants. T-N removal efficiencies approximately doubled in percentage terms at the 2 hrs of reaction time and 700 ppm of coagulants addition and applied current density of $1.76A/dm^2$ due to the increase of free residual chlorine such as HOCl caused by increase of electrolyte concentration through the addition of inorganic coagulants. Under the same experimental condition, more than 90% of T-P removal efficiencies was obtained. The reason can be explained that increase of chemical adsorption rate between phosphate and insoluble metal compounds caused by dissolved oxygen generated from anode by the increased electrolyte concentration through inorganic coagulants addition make a major role in improving T-P removal efficiencies. It can be concluded that inorganic coagulants addition as the supplemental agent of electrolyte is effective way in improving organic and nutrient salt removal efficiency when treating hospital wastewater having low electrolyte concentration.

A Study on the high-speed Display of Radar System Positive Afterimage using FPGA and Dual port SRAM (FPGA와 Dual Port SRAM 적용한 Radar System Positive Afterimage 고속 정보 표출에 관한 연구)

  • Shin, Hyun Jong;Yu, Hyeung Keun
    • Journal of Satellite, Information and Communications
    • /
    • v.11 no.4
    • /
    • pp.1-9
    • /
    • 2016
  • This paper was studied in two ways with respect to the information received from the video signal separation technique of PPI Scop radar device. The proposed technique consists in generating an image signal through the video signal separation and synthesis, symbol generation, the residual image signal generation process. This technology can greatly improve the operating convenience with improved ease of discrimination, screen readability for the operator in analyzing radar information. The first proposed method was constructed for high-speed FPGA-based information processing systems for high speed operation stability of the system. The second proposed method was implemented intelligent algorithms and a software algorithm function curve associated resources.This was required to meet the constraints on the radar information, analysis system. Existing radar systems have not the frame data analysis unit image. However, this study was designed to image data stored in the frame-by-frame analysis of radar images with express information MPEG4 video. Key research content is to highlight the key observations expresses the target, the object-specific monitoring information to the positive image processing algorithm and the function curve delays. For high-definition video, high-speed to implement data analysis and expressing a variety of information was applied to the ARM Processor Support in Pro ASIC3.

Study on Electro-optic Characteristics of the Optically Compensated Bend Liquid Crystal Display Using UV Curable Monomer (광경화성 단분자를 이용한 광학 보상 휨 액정 디스플레이의 전기광학 특성연구)

  • Lim, Young-Jin;Jeon, Eun-Jeong;Kwon, Dong-Won;Kim, Jeong-Hwan;Jeong, Kwang-Un;Lee, Myong-Hoon;Lee, Seung-Hee
    • Polymer(Korea)
    • /
    • v.33 no.5
    • /
    • pp.496-500
    • /
    • 2009
  • Optically compensated bend liquid crystal display (OCB-LCD) has many application fields owing to its fast response time and wide viewing angle. However, in order to operate the OCB-LCD in bend state, this device needs quick transitions from the initial splay state to bend state. Unlike conventional approach using transient high voltage for the transition, the OCB-LCD with high surface tilt angle, which was achieved by polymerization of UV curable reactive mesogen monomer under certain voltage, was manufactured and the cell showed bend state initially. Electro-optic and electrical characteristics of the cell were analyzed. The cell shows a fast response time owing to high surface pretilt angle and very low residual DC less than 0.1 V although another polymer layer is formed above polymer alignment layers.

Evaluation of Cellotape Anal Swabs in the Diagnosis of enterobiasis (요충층에 있어서 항문주위 도말법의 검토)

  • Kim, Jong-Seong;Choi, Hyang-Hee;Joo, Kyoung-Hwan;Rim, Han-Jong
    • Journal of agricultural medicine and community health
    • /
    • v.12 no.1
    • /
    • pp.94-101
    • /
    • 1987
  • Enterobiasis is common helminthic infections found in man. But control of this disease is still troublesome because of its difficulty in the d diagnosis and prevention of infection. Considering the difficulty of accurate diagnosis of pinworm infection, which is very common and somewhat pathogenic, reevaluation of cellotape anal swab method for the diagnosis of enterobiasis was performed. A total of 147 children ranging the ages of 1-12 years in 3 orphanages in the suburbs of Seoul, Korea was subjected for this study. Repeated cellotape anal swabs were carried out against 70 children, 7 times for 3 days interval, in the morning 6am. Finally 10 mg/kg body weight pyrantel pamoates were given to all children including egg negative cases and whole stools of 3 following successive days were collected for the confirmation of residual worm ourden at the time of treatment. Cellotape anal swabs were also performed to another 77 children at 6am, 3pm, 9pm, twice for 3 days interval. The resultant findings were summarized as follows; 1) While the each time average detection rate of Enterobius egg was 28.8% in this study group, the accumulative detection rate up to 7th examination was 62.8%. The accumulative detection rate rose continuously up to 6th examination. 2) After administration of pyrantel pamoate 10 mg/kg body weight, final infection rate was increased to 72.9% by adding worm positive cases who didn't show any evidence of infection in the cellotape anal swabs. 3) Although pinworms were detected in 35 among 70 children treated, 7 cases (20%) of them were egg negative cases in 7 consecutive cellotape anal swabs. 4) Pinworms were expelleded in 14 (87.5%) among 16 children whose swab result was positive in the last examination which was done concurrently with drug administration. 5) Estimated infection rate calculated by best asymptotically normal estimate of Neuman from Moriya's modification revealed 71.5% similar to 72.9% of present results. 6) The result of anal swab performed at 6am was higher than that of 3pm or 8pm. In conclusion, cellotape anal swab method for Enterobius vermicularis infection was considered as method having relatively high positive accuracy. However to gain the reliable infection rate, at least 6 examination is required in the group with 25-30% infection rate by single swab. Moriya's modification of Neuman could be used efficiently in the mass control of this diease for the estimation of true infection rate of E. vermicularis in the sampled population.

  • PDF

A CHANGE OF THE SALIVARY FLUORIDE CONCENTRATION AFTER FLUORIDE-CONTAINING TAPE APPLICATION (불소 테잎 적용 후 시간변화에 따른 타액 내 불소농도)

  • Park, Seung-Hyo;Lee, Sang-Ho;Lee, Nan-Young
    • Journal of the korean academy of Pediatric Dentistry
    • /
    • v.36 no.3
    • /
    • pp.377-384
    • /
    • 2009
  • The purpose of this study is to investigate the residual fluoride concentration of fluoride tape in oral cavity which made by spraying NaF on carboxymethylcellulose base. After 1, 3, 5, 7 hours and 1, 2, 3 days of applicating APF gel(60seconds $taste^{(R)}$, 1.23% APF gel, Group I), Fluoride varnish($CavityShield^{TM}$, 5% NaF, Group II) and Fluoride tape(SCMC-T-5, 5% NaF, Trial product, Group III) in oral cavity of 27 healthy adults in their twenties, the result of fluoride concentration in unstimulated whole saliva which measured by using fluoride sensitive electrode made up to following conclusion. 1. Until 7 hours after application in every group, it showed significantly higher fluoride concentration in saliva than baseline value but at 1, 2, 3 days after application, there were no significant differences between measurements and baseline value(p>0.05). 2. Until 7 hours after application at every time, mean fluoride concentration in saliva was higher in the order of Group II, I and III. 3. 1 hour and 3 hours after application, Group II revealed significantly higher fluoride concentration than Group III(p<0.05), but there were no significant differences between Group Ⅰ and Group III in every time.

  • PDF

Preparation and Characterization of Ferrite Supported on Porous Ceramic Fiber Composites for Co2 Decomposition (이산화탄소 분해용 페라이트 담지 다공성 세라믹 섬유복합체 제조와 물성)

  • Lee, Bong-Soo;Kim, Myung-Soo;Choi, Seung-Chul;Oh, Jae-Hee;Lee, Jae-Chun
    • Journal of the Korean Ceramic Society
    • /
    • v.39 no.8
    • /
    • pp.801-806
    • /
    • 2002
  • The decomposition and/or conversion of carbon dioxide to carbon have been studied using oxygen-deficient ferrites for the reduction of $CO_2$ emission to the atmosphere. In this work, the homogeneous precipitation method using urea decomposition was employed to induce in situ precipitation of Ni ferrite($Ni_{0.4}Fe_{2.6}O_4$) on the porous ceramic fiber support (50 mm diameter${\times}$10 mm thickness). Effects of ferrite loading conditions on the CO2 decomposition efficiency were discussed in this paper. Removal of residual chloride ions and urea by solvent exchange from the porous media after ferrite deposition apparently helps to form spinel ferrite, but does not increase the efficiency of $CO_2$ decomposition. Porous ceramic fiber composites containing 20 wt% (1g) ferrite samples showed 100% efficiency for $CO_2$decomposition during the first three minutes, but the efficiency decreased rapidly after the elapsed time of ten minutes. The characteristic reduction time for the $CO_2$ decomposition efficiency was estimated as about 3∼7 min.

Energy-Efficient Data-Aware Routing Protocol for Wireless Sensor Networks (무선 센서 네트워크를 위한 에너지 효율적인 데이터 인지 라우팅 프로토콜)

  • Lee, Sung-Hyup;Kum, Dong-Won;Lee, Kang-Won;Cho, You-Ze
    • Journal of the Institute of Electronics Engineers of Korea CI
    • /
    • v.45 no.6
    • /
    • pp.122-130
    • /
    • 2008
  • In many applications of wireless sensor networks, sensed data can be classified either normal or urgent data according to its time criticalness. Normal data such as periodic monitoring is loss and delay tolerant, but urgent data such as fire alarm is time critical and should be transferred to a sink with reliable. In this paper, by exploiting these data characteristics, we propose a novel energy-efficient data-aware routing protocol for wireless sensor networks, which provides a high reliability for urgent data and energy efficiency for normal data. In the proposed scheme, in order to enhance network survivability and reliability for urgent data, each sensor node forwards only urgent data when its residual battery level is below than a threshold. Also, the proposed scheme uses different data delivery mechanisms depending on the data type. The normal data is delivered to the sink using a single-path-based data forwarding mechanism to improve the energy-efficiency. Meanwhile, the urgent data is transmitted to the sink using a directional flooding mechanism to guarantee high reliability. Simulation results demonstrate that the proposed scheme could significantly improve the network lifetime, along with high reliability for urgent data delivery.

Survey on Revision and Complements for the Current Curriculum of Herbology (한의과대학 본초학 교육과정의 개정 및 보완을 위한 설문조사 연구)

  • Kim, Hong-Jun;Choi, Go-Ya;Kim, Chul;Lee, Guem-San;Kim, Jung-Hun;Lee, Seung-Ho;Hwang, Sung-Yeoun;Ju, Young-Sung
    • The Journal of Korean Medicine
    • /
    • v.30 no.4
    • /
    • pp.118-128
    • /
    • 2009
  • Objects: This study was conducted to investigate the current educational environment of herbology and to develop a future-oriented curriculum for oriental medicine. The questionnaire used in this research was drawn up based on the current curriculum referring to the current curriculum of herbology and pharmacognosy. Methods: The survey was carried out presenting the questionnaires to a total 12,754 of the students and doctors of oriental medicine through e-mailing five times; of these, 2,074 replied. Results: 1. Among the respondents, about 97% agreed that it was necessary to revise and complement the current curriculum of herbology. 2. The respondents felt that the assigned lecture time of subject was "sufficient" (19%), "insufficient" (39%) and "average" (39%), respectively, and the level of lecture was "insufficient" (37%) or "average" (43%) respectively. According to priority, it showed that the contents which needed complement in lecture were discrimination of medicinal herbs (24%), practical use of action and indications (23%), and correlation with modern disease (21%). In theoretical lectures, 69% of the respondents agreed on the introduction of natural scientific methods 3. In practice, 51% of the respondents replied that the lecture time for practice was insufficient. The contents which needed to be complemented in practice were as follows: audio-visual materials for discrimination of medicinal herbs (22%), concrete exercise for the processing of medicinal herbs (21%), and attempts for the objective discrimination of medicinal herbs using instruments (microscope, analytical instrument, residual pesticide, heavy metal, genetic analysis) (16%). 70% replied that the discrimination of medicinal herbs of high price and rarity was "none or insufficient". 4. 56% replied that it was necessary to introduce and practice physicochemical analysis, and they showed higher requests according to the increase of their educational level. However, 86% replied that they had never experienced concrete attempts for objective discrimination of medicinal herbs, which seemed to indicate that, excepting some schools, practice exercise was rarely performed. Conclusions: According to results, it seems that an urgent review on the current course of herbology and a workshop on the process of experimental practice for professors is needed.

  • PDF