• Title/Summary/Keyword: Injection-rate

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Application of SNCR/SCR Combined process for effective operation of SCR Process

  • 최성우;최상기
    • Journal of Environmental Science International
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    • v.12 no.1
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    • pp.47-54
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    • 2003
  • This paper have examined the optimum combination of SNCR and SCR by varying SNCR injection temperature and NSR ratio along with SCR space velocity. NOx reduction experiments using a SNCR/SCR combined process have been conducted in simple NO/NH$_3$/O$_2$ gas mixtures. Total gas flow rate was kept constant 4 liter/min throughout the SNCR and SCR reactors, where initial NOx concentration was 500 ppm in the presence of 5% O$_2$. Commercial catalyst, sulfated V$_2$O$\_$5/-WO$_3$/TiO$_2$, was used for SCR NOx reduction. The residence time and space velocity were around 1.67 sec, 2,400 h$\^$-1/ and 6,000 h$\^$-1/ in the SNCR and SCR reactors, respectively. SNCR NOx reduction effectively occurred in a temperature window of 900-950$^{\circ}C$. About 88% NOx reduction was achieved with an optimum temperature of 950$^{\circ}C$ and NSR=1.5. SCR NOx reduction using commercial V$_2$O$\_$5/-WO$_3$-SO$_4$/TiO$_2$ catalyst occurred in a temperature window of 200-450$^{\circ}C$ 80-98% NOxreduction was possible with SV=2400 h$\^$-1/ and a molar ratio of 1.0-2.0. A SNCR/SCR(SV=6000 h$\^$-1/) combined process has shown same NOx reduction compared with a stand-alone SCR(SV=2400 h$\^$-1/) unit process of 98% NOx reduction. The NH$_3$-based chemical could routinely achieve SNCR/SCR combined process total NOx reductions of 98% with less than 5 ppm NH$_3$ slip at NSR ranging from about 1.5 to 2.0, SNCR temperature of 900$^{\circ}C$-950$^{\circ}C$, and SCR space velocity of 6000 h$\^$-1/. Particularly, more than 98% NOx reduction was possible using the combined process under the conditions of T$\_$SNCR/=950$^{\circ}C$, T$\_$SCR/=350$^{\circ}C$, 5% O$_2$, SV=6000 h$\^$-1/ and NH$_3$/NOx=1.5. A catalyst volume was about three times reduced by SNCR/SCR combined process compared with SCR process under the same controlled conditions.

Analysis of Polar Maps of Dipyridamole Stress/Rest $^{99m}Tc$-MIBI Myocardial SPECT in 14 Healthy Young Men (건강한 청년 남자 14 례에서 Dipyridamole 부하 $^{99m}Tc$-MIBI 심근 SPECT 극성지도의 분석)

  • Cho, Ihn-Ho;Sin, Dong-Gu;Lee, Hyoung-Woo;Kim, Young-Jo;Shim, Bong-Sup;Lee, Hyun-Woo
    • Journal of Yeungnam Medical Science
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    • v.11 no.1
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    • pp.146-152
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    • 1994
  • We performed the same day dipyridamole stress/rest myocardial SPECT in 14 healthy young men, reconstructed the polar maps according to Cedars-Sinai method and quantitated the radioactivity of myocardial wall. We divided the whole myocardium to 9 sectors. The latero-anterior wall contains the highest count. The infero-septal wall contains the lowest count. There isn't any significant differences of radioactivity in each segment between stress and rest polar map. The hemodynamic parameters after dipyridamole injection in the subjects were significantly changed except systolic blood pressure : the heart rate was increased and diastolic blood pressure was decreased. Adverse effects were reported in 85.7%. We suggest that these data can be used to dectect perfusion defect in the coromary artery disease.

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Contrast Enhanced Cerebral MR Venography: Comparison between Arterial and Venous Triggering Methods (조영 증강 자기공명정맥 촬영술에서의 동맥과 정맥 triggering 방법의 비교)

  • Jang, Min-Ji;Choi, Hyun-Seok;Jung, So-Lyung;Ahn, Kook-Jin;Kim, Bum-Soo
    • Investigative Magnetic Resonance Imaging
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    • v.16 no.2
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    • pp.152-158
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    • 2012
  • Purpose : To compare the arterial and venous detection sites of triggering methods in contrast-enhanced-MR-venography (CE-MRV) for the evaluation of intracranial venous system. Materials and Methods: 41 healthy patients underwent CE-MRV with autotriggering at either the cavernous segment of internal carotid artery with an inserted time-delay of 6 seconds (n = 20) or the superior sagittal sinus without any timedelay (n = 21). 0.1 mmol/kg gadolinium-based contrast material ($Magnevist^{(R)}$, Schering, Germany) was intravenously injected by hand injection. A sagittal fast-spoiled-gradient-echo-sequence ranging from one ear to the other was performed (TR/TE5.2/1.5, Matrix $310{\times}310$, 124 sections in the 15-cm-thick volume). 17 predefined venous structures were evaluated on all venograms by two neuroradiologists and defined as completely visible, partially visible, or none visible. Results: The rate of completely visible structures were 272 out of 323 (84%) in the arterial triggering CE-MRV and 310 out of 340 (91%) in the venous triggering CE-MRV. The venous triggering CE-MRV demonstrated an overall superior visualization of the cerebral veins than the arterial triggering CE-MRV (Fisher exact test, p < 0.006). Conclusion: CE-MRV using venous autotriggering method provides higher-quality images of the intracranial venous structures compared to that of arterial.

Tracer Experiment for the Investigation of Urban Scale Dispersion of Air Pollutants - An Improved Method for the Release and Determination of Perfluorocarbon Tracers in the Urban Atmosphere (추적자 확산 실험에 의한 서울 도심 확산 현상 연구 - 도시규모 대기확산 실험을 위한 PFCs 추적자 방출 및 분석 시스템의 개발 및 적용 연구)

  • Yoo, Eun-Jin;Lee, Chong-Bum;Ro, Chul-Un;Kim, Hye-Kyeong;Lee, Gang-Woong
    • Journal of Korean Society for Atmospheric Environment
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    • v.23 no.5
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    • pp.547-556
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    • 2007
  • The release, sampling and analytical methods have been developed and tested for perfluorocarbons (PFCs) atmospheric tracers in order to gain insight into the atmospheric transport and dispersion over the urban conditions of Seoul, Korea. Although PFCs tracer experiments provide unique opportunities to test local and urban scale of transport and dispersion, no previous experiment with PFCs has been conducted in Korea. PMCH and PDCH were chosen as targeted tracers in our study due to their extreme low ambient concentrations and great sensitivities among various PFCs. For PFCs release system, a set of micro-metering pump, electronic balance, vaporizing furnace and high speed blower was constructed for precise and accurate release of tracers. The precision of released rate by this system was estimated to be 1%. Samplings of PFCs were carried out by fabricated portable air samplers with micro pumps and rotameters into glass tubes packed with 150 mg of Carboxen-569. The uncertainty of these sampling system was maintained below 14%. PMCH and PDCH were quantified in GC/ECD with preconditioned injection system to eliminate the interference compounds using traps and subsequent catalytic conversion system prior to column separation. Three intensive field test were undertaken during the springtime of 2002 to 2004 in eastern part of Seoul. Daily background samples were collected to characterize the background levels of PMCH and PDCH prior to their release. The observed background concentrations of PMCH ranged from 3.5 to 10.1 fL/L and varied randomly in location and time in this study. Its mean and standard variation of background concentration ($6.8{\pm}1.9\;fL/L$) are higher than those ($3.2{\sim}5.8\;fL/L$) of other historic tracer studies. Identified uncertainty for background PMCH was $1.7{\sim}2.0\;fL/L$ using this analytical system. Combined relative uncertainty in determining the tracer's concentrations was estimated as 17%. However, its background concentrations and uncertainty in concentration determination were found to be low and stable enough for tracer study.

Effects of Sweet Bee Venom Pharmacopuncture and Low Level Laser Acupuncture on a Rat Model with Complete Freund's Adjuvant-induced Arthritis (Sweet 봉약침과 저준위 레이저침이 Complete Freund's Adjuvant로 유발된 관절염 백서 모델에 미치는 영향)

  • Lee, Jung Hun;Kim, Kyeong Ok;Kim, Kyeong Su;Park, Soo Yeon;Yang, Seung Joung;Choi, Chang Won;Na, Chang Su;Wei, Tung Shuen
    • Journal of Acupuncture Research
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    • v.32 no.3
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    • pp.1-13
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    • 2015
  • Purpose : This research was conducted to investigate the effect of sweet bee venom pharmacopuncture and low level laser acupuncture on paw edema, pain index, anti-inflammatory factor, AST, ALT and complete blood cell count of a rat model with Complete Freund's Adjuvant-induced arthritis. Methods : Five experimental groups were formed with each consisting of six rats: normal group, control group, sweet bee venom pharmacopuncture group, lower level laser acupuncture group, and sweet bee venom pharmacopuncture, lower level laser acupuncture group. The experimental model of arthritis was induced by two injections of Freund's adjuvant into the left knee joint of Sprague Dawley(SD) rats. The second injection of Freund's adjuvant was given ten days after the first one. Ten days later, sweet bee venom pharmacopuncture and low level laser acupuncture were administered separately or together by assigned groups at $GB_{34}$ and $GB_{39}$ of rats twice a week for a total of six times. Thereafter, edema rate, pain index, tumor necrosis factor-${\alpha}$, interleukin-6, aspartate aminortansferase, alanine aminotransferase and complete blood cell count were measured. Results : We noticed synergic effects of sweet bee venom pharmacopuncture and low level laser acupuncture according to the results of the paw edema and Von Frey pain index. The sweet bee venom pharmacopuncture(BVA) and sweet bee venom pharmacopuncture+ low level laser acupuncture(BVA+LLA) groups experienced a more significant effect when compared with the control group. Conclusions : These results suggest that Sweet Bee Venom Pharmacopuncture and low level laser acupuncture at GB34 and GB39 have a significant anti-inflammatory effect on Freund's adjuvant arthritis in rats.

Use of Sprinkler System for Production Forest Management of Pine Mushroom (Tricholoma matsutake) (살수장치(撒水裝置)를 이용(利用)한 송이산 관리(管理)에 관(關)한 연구(硏究))

  • Chung, Sang Bae;Kim, Chul Su
    • Journal of Korean Society of Forest Science
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    • v.94 no.1 s.158
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    • pp.21-25
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    • 2005
  • In order to prevent the pine mushrooms, Tricholoma matsutake, from being damaged by the pine needle gall midges, Thecodiplosis japonensis, and thereby, to increase their production and improve their quality, a sprinkler system was installed on the mushroom field. A low-concentration insecticide (deltamethrin 1% EC, x2,000) was sprayed once at insects' most active time every day during the period of insects' adult occurrence and thereafter, the irrigation by ground water spraying was periodically enforced. Such a test was conducted at Yangyang-Gun, Kwangwon-do, Korea for 2 years from 2000 through 2001. The pine needle gall midges generally emerged for about 40 days from late May to early July. 50% emergence of them was about June 6, and peak emergence (more than 80%) was early or mid-June. Gall formation rate was 3.5% on average with this ground insecticide spraying, while 51.3% when not treated. Control effectiveness of this insecticide spraying was 92.3%, which was higher than 82.5% by the conventional injection of insecticide into tree stems. Pine mushrooms emerged for about 35 days from mid-September through earlier October, and around 80% of them did for about 15 days from late September through early October. As a result of the periodic ground water-spraying (30 mm per week) for 2 months (from August to October), the production of mushrooms increased by 74.3% (110% in terms of weight), with their quality improvement. The mushrooms produced from the treated stand by the spraying system were priced 8,670,000 wons per hectare, and thus, the net income deducting the facility and management cost was 4,310,000 wons, about 5% higher than value from the control stand. It was analyzed that this treatment was significantly cost effective when the facilities are used more than 5 years.

Effects of Continuous Epidural Infusion of Buprenorphine for Postoperative Pain Management (수술후 통증관리를 위한 Buprenorphine의 지속적 경막외 투여효과)

  • Yoon, Hee-Dong;Park, Young-Cheol;Lim, Hae-Ja
    • The Korean Journal of Pain
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    • v.9 no.1
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    • pp.151-158
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    • 1996
  • Background: Buprenorphine, a new synthetic thebaine derivative, is a partial agonist of the opioid $\mu$-receptor with high receptor affinity, great lipid solubility, and slow rate of opiate receptor association and dissociation. Continuous epidural infusion of opioid can possibly produced undesirable effects, such as respiratory depression, pruritus, etc, in spite of effective postoperative analgesia. Methods: The present study was undertaken to compare the analgesic properties and side effects of continuous epidural infusion of buprenorphine combined with bupivacaine, and morphine combined with bupivacaine in 90 patients following elective gynecologic lower abdominal surgery. At the end of surgery, the initial bolus doses were 3 mg morphine (M group), 0.15 mg buprenorphine (0.15B group), 0.3 mg buprenorphine (0.3B group) combined with 0.25% bupivacaine 10ml, and subsequent continuous infusion doses were 6 mg morphine plus 0.125% bupivacine 100 ml (M group) and 0.6mg buprenorphine plus 0.125% bupivacaine 100 ml (0.15B, 0.3B, group) during 48 hours. The assessment of analgesic efficacy and side effects were made at arrival of recovery room, 1 hr, 4 hr, 8 hr, 24 hr, 36 hr, and 48 hr after the epidural injection. Results: The pain score during 48 hours was significantly higher in the 0.15B group than in the M group and 0.3B group (P<0.05), and the number of patients requiring additional analgesics was significantly higher in the 0.15B group than in the M group and 0.3B group (P<0.05). Signs of respiratory depression were not noted, and the incidence of pruritus, nausea, and vomiting was slightly lower in the 0.15B group and 0.3B group than in the M group, and the incidence of sedation and urinary retention was similar in three group. The subjective rating of satisfaction was better in the 0.3B group than in the M group and 0.15B group (P<0.05). Conclusion: The above results suggest that continuous epidural infusion of buprenorphine combined with low-dose bupivacaine is an advisable method of postoperative analgesia.

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Geological Structures and Their Relation to Groundwater System around K-1 Oil Stockpile (K-1 기지 주변 지질 구조와 지하수위 변동 특성)

  • Moon, Sang-Ho;Kim, Young-Seog;Ha, Kyoo-Chul;Won, Chong-Ho;Lee, Jin-Yong
    • Economic and Environmental Geology
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    • v.43 no.2
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    • pp.149-162
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    • 2010
  • The most serious problem in oil stockpiles with artificial underground cavern is maintaining the stability of ground water system. In order to understand the ground water system around K-1 site, we determined the regional flow direction and level distribution of groundwater, and investigated the major geologic factors influencing their flow system. Reactivated surface along the contact between granite and gneiss, and fractures and faults along the long acidic dyke may contribute as important pathways for groundwater flow. Within K-1 site, groundwater level fluctuation is closely related to the rainfall events and injection from surface or influx water. In this project, the effect of groundwater pumping from the southern wells was examined. Based on equations relating water level drawdown to pumping rate at those wells, their pumped outflow of groundwater ranged from $80\;m^3$/day to less than $250\;m^3$/day. The modeling results with MODFLOW imply that the previous groundwater pumping at distance of 1.2 km may not affect the groundwater level variations of the K-1 site. However, continuous pumping work at quantity over $250\;m^3$/day in this area will be able to affect the groundwater system of the K-1 site, particularly along the acidic dyke.

Cholinergic Mechanisms on Cardiovascular Regulation in the Ventrolateral Medulla of the Rat (흰쥐 복외측 연수에서 심혈관 조절에 대한 Choline성 기전)

  • Kim, Seong-Yun;Koh, Taek-Lip;Lee, Sang-Bok
    • The Korean Journal of Pharmacology
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    • v.23 no.2
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    • pp.77-85
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    • 1987
  • This study was carried out to determine the role of cholinoceptors in the ventrolateral medulla on central control of blood pressure (BP) and heart rate (HR). In rats anesthetized with urethane and paralyzed, microinjections of the neuroexcitatory amino acid L-glutamate (300 ng/site) were performed to functionally identity the vasopressor area (VLPA) and the vasodepressor area (VLDA) in the ventrolateral medulla oblongata. 1. The bilateral microinjection of carbachol (300 ng/site) into the VLPA produced significantly an increase in BP and HR which was not blocked by bilateral pretreatment of hexamethoium ($4\;{\mu}g/site$). 2. The bilateral microinjection of physostigmine (200 ng/site) and oxotremorine (300 ng/site) into the VLPA produced significantly an increase in BP respectively. 3. The bilateral microinjection of atropine ($4\;{\mu}g/site$) into the VLPA produced significantly a decrease in BP and HR. 4. The bilateral micro injection of acetylcholine (500 ng/site) and dimethylphenylpiperazinium (500 ng/site) into the VLDA produced significantly a decrease in BP and HR respectively. 5. The depressor and bradycardiac responses elicited by the bilateral microinjection of acetylcholine (500 ng/site) into the VLDA were blocked by bilateral pretreatment of hexamethonium ($4\;{\mu}g/site$). The results suggest that the activation of cholinoceptors in VLPA produce hypertensive and tachycardiac responses which may be mediated by muscarinic receptors, and the activation of cholinoceptors in VLDA produce hypotensive and bradycardiac responses which may be mediated by nicotinic receptors.

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Investigation of Dental Plaque, Calculus and Gingival Inflammation in Beagle Dogs (비글견에서 치태와 치석, 치은 염증의 조사)

  • Kim Joong-hyun;Ryu Hak hyun;Lee Jae yeong;Han Kyu-bo;Kim So-seob;Kang Seong soo;Bae Chun sik;Choi Seok hwa
    • Journal of Veterinary Clinics
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    • v.22 no.1
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    • pp.31-35
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    • 2005
  • This study was performed to investigate of dental plaque, calculus and gingival inflammation in Beagle dogs. Forty adults Beagle dogs (28 male and 12 female) were used in this study. The dogs weighed 9.5 kg and were in good oral and systemic health as determined by physical examination, and all dogs had full and normal dentition. The dogs were given a commercial pellet feed during 2 years period. For all examination procedures, the dogs were premedicated with a subcutaneous injection of atropine sulfate (0.04 mg/kg). Anesthesia was induced and maintained by intravenous administration of ketamine (8 mg/kg) and xylazine (2 mg/kg). Dental plaque, calculus and gingival inflammation were assessed by Logan and Boyce clinical plaque index. Calculi covering the maxillary carnassial and first molar teeth were extensive and were accompanied by severe gingival inflammation and pocket formation. Calculi, accompanied by gingival inflammation, were clearly evident on buccal surfaces of other teeth. Calculi didn't showed on the lingual surfaces, but linguogingival inflammation formed in premolar teeth. Although the general pattern was clear, there was considerable variation among dogs in the rate of deposition of calculus and extend of gingival inflammation. This investigation suggest that feeding of the commercial dry food without dental hygiene increase plaque accumulation and may be a contributing factor in calculi formation and periodontal disease.