• 제목/요약/키워드: plasma flow

검색결과 1,179건 처리시간 0.03초

PLASMA ALLANTOIN CONCENTRATION IN RESPONSE TO CHANGES IN NUTRITIONAL STATUS OF CALVES

  • Kagiyama, K.;Funaba, M.;Iriki, T.;Abe, M.
    • Asian-Australasian Journal of Animal Sciences
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    • 제9권2호
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    • pp.165-170
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    • 1996
  • Two experiments were conducted to search factor(s) affecting the plasma allantoin concentration in infant calves. In experiment 1, five male Holstein calves aged 1 week were given only milk replacer free from nucleic acids for 28 days Plasma allantoin concentration varied in a reverse proportion to daily amounts of milk replacer, and the concentration when calves received 750 g/d of milk replacer was significantly lower than that when they received 250 g/d. Contrary to plasma allantoin concentration, glomerular filtration rate(GFR) was directly proportional to daily amounts of milk replacer, leading to a constant filtration of allantoin across the glomeruli. Renal handling of allantion was also unaffected by the amount of milk replacer, resulting in the constant urinary excretion of allantoin. These results suggested that GFR, which was affected by the nutritional status, could affect plasma allantoin concentration. In experiment 2, the effect of age-related changes in nutritional status after weaning on GFR was examined in eight calves weaned at 5 weeks of age. The GFR expressed as body weight basis was lower immediately after weaning, but linearly increased up to the 19th week post-weaning. The present results suggested that the changes in GFR in response to nutritional status would be one of the possible causes of atypical plasma allantoin concentration immediately after weaning. We conclude that plasma allantoin concentration would not be a proper estimator of intestinal flow of microbial protein in cattle.

Effects of OH Radical Density from Atmospheric Plasma to Induce Cell Death in Lung Cancer and Normal Cells

  • 박대훈;김용희;심건보;백구연;엄환섭;최은하
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.254.1-254.1
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    • 2014
  • Atmospheric plasma's electron temperature is less than thermal plasma, so it is useful at bio experiment. We have investigated the optical emission spectroscopy (OES) lines by spectrometer during Atmospheric plasma bombardment onto the PBS surface by using an Ar gas flow. Also we have measured the OH radical density inside the solution induced by the Atmospheric plasma bombardment. OH radical species are appeared at 308 nm and 309 nm. Densities of OH radical species has been found to be significantly decreased versus depth of the solution from 2 mm to 6 mm. OH radical density inside the PBS is measured to be about $1.87{\times}1016cm-3$ downstream at 2 mm from the surface under optimized Ar gas flow of 200 sccm in Atmospheric plasma. Also we have investigated cell viability of lung cancer and normal cell after Atmospheric plasma treatment for fixed exposure time in 60 seconds, but different depths. We used SEM, we observed change of cell morphorogy, did experiment about FDA & PI Staining method. It is found that there is selectivity between the lung cancer and lung normal cell, in which cancer cell definitely has higher cell death ratio more than normal cell. We have investigated change of bond structure in FT-IR spectroscopy, the following peaks were observed: and intense O-H peak at 3422 cm-1 and at 2925 cm-1 corresponds to C-H stretch vibrations of methylene group.

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한국형(韓國型) 출혈열(出血熱)에서의 Renogram에 대(對)한 연구(硏究) (A Study of Renogram in Korean Hemorrhagic Fever)

  • 최태규;이정상;고창순;이문호
    • 대한핵의학회지
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    • 제8권1_2호
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    • pp.13-24
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    • 1974
  • The patterns of renogram in patients with Korean hemorrhagic fever were evaluated with clinical course and renal hemodynamic changes in various clinical stages. The renal plasma flow was measured by hippuran blood clearance using $^{131}I$-ortho-iodohippurate and hippuran renogram was analysed by means of quantitative and qualitative methods in 26 patients of Korean hemorr hagic fever. The results obtained with this study were as follows; 1. During the oliguric phase of Korean hemorrhagic fever, the renogram showed non-functioning (flat) or obstructive pattern. The group of patients with non-functioning pattern of renogram had more severe impairement of renal function and grave prognosis than the group with obstructive pattern of renogram. 2. During the diuretic phase, the renogram showed obstructive or dysfunction or normal pattern, which was related with the recovery of renal function. Obstruction pattern of renogram was observed till the 2nd week of diuretic phase. Normal pattern of renogram began to appear by the 2nd week of diuretic phase. 3. During the convalescent phase of Korean hemorrhagic fever, 40% of patients showed dysfunnction pattern of renogram, and the recovery of abnormal renogram in Korean hemorrhagic fever was more delayed than the recovery of clinical features and laboratory findings. 4. The renogram showed normal pattern 6 months after onset of Korean hemorrhagic fever in all cases. 5. There was significant correlationship between the pattern of renogram and the decreace of renal plasma flow in the patients with Korean hemorrhagic fever. The decreace of renal plasma flow was maked in the patients with non-functioning pattern of renogram and was least in the patients with dysfunction pattern of renogram. All above results suggested that the renogram reflects the effective renal plasma flow and degree of renal impairement, and the renogram may be one of the important indexes which could give us a more precise prognosis in Korean hemorrhagic fever.

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이류체 노즐을 이용한 가스의 용존율 향상 (Improvement of Gas Dissolution Rate using Air Atomizing Nozzle)

  • 김동석;박영식
    • 한국환경과학회지
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    • 제27권3호
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    • pp.219-225
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    • 2018
  • This study was conducted to investigate the possibility of utilizing various types of nozzles and gas-liquid mixers to increase the dissolution rate of plasma gas containing ozone generated in a dielectric barrier plasma reactor. After selecting the air atomizing nozzle with the highest gas dissolution rate among the 13 types of test equipment, we investigated the influence of the operating factors on the air atomizing nozzle to determine the optimal plasma gas dissolution method. The gas dissolution rate was measured by a simple and indirect method, specifically, the measurement of KLa instead of direct measurement of ozone concentration, which requires a longer analysis time. The results showed that the KLa value of the simple mix of air and water was $0.372min^{-1}$, Which is 1.44 times higher than that ($0.258min^{-1}$) of gas emitted from a normal diffuser. Among the nozzles of the same type, the KLa value was highest for the nozzle having the smallest orifice diameter. Among the 13 types of devices tested, the nozzle with highest KLa value was the M22M nozzle, which is a gas-liquid spray nozzle. The relationship between water circulation flow rate and KLa value in the experimental range was linear. The air supply flow rate and KLa value showed a parabolic-type correlation, while the optimum air supply flow rate for the water circulation flow rate of 1.8 L / min is 1.38 times.

워터젯 글라이딩 아크 플라즈마를 이용한 사불화탄소 저감 (Reduction of Tetrafluoromethane using a Waterjet Gliding Arc Plasma)

  • 이채홍;전영남
    • Korean Chemical Engineering Research
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    • 제49권4호
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    • pp.485-490
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    • 2011
  • 사불화탄소($CF_4$)는 반도체 제조공정에서 에칭과 반응기 세척에서 사용되어온 가스이다. $CF_4$는 적외선을 강하게 흡수하고 대기 중 잔류시간이 길어서 지구온난화에 영향을 미치기 때문에 고효율의 분해가 필요하다. 본 연구에서는 플라즈마와 워터젯을 결합하여 워터젯 글라이딩 아크 플라즈마 시스템을 개발하고, 이를 이용하여 $CF_4$를 고효율로 분해할 수 있도록 방전영역을 증가시키고 다량의 OH 라디칼을 생성시킬 수 있는 최적의 조업 조건을 결정하였다. 공정 실험 변수로는 워터젯 주입량, $CF_4$ 초기 농도, 전체 가스량과 주입에너지량(SEI : Specific energy input)을 선정하였다. 변수실험을 통하여 워터젯 주입량이 25.5 mL/min, $CF_4$ 초기 농도 2.2%, 전체 가스량 9.2 L/min, SEI 7.2 kJ/L일 때 $CF_4$ 분해율은 최고 97%까지 도달하였다.

무마취 가토 신장기능에 미치는 Atrial Natriuretic Factor의 영향 (Effect of Atrial Natriuretic Factor on the Renal Function and Renin Release in Unanesthetized Rabbit)

  • 이준규;조경우
    • The Korean Journal of Physiology
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    • 제20권1호
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    • pp.103-124
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    • 1986
  • Since it has been suggested that atrial receptor may be involved in the mechanism of extracellular volume regulation, it was shown that the granularity of atrial cardiocytes can be changed by water and salt depletion, and that an extract of cardiac atrial tissue, when injected intravenously into anesthetized rats, was shown to cause a large and rapid increase in renal excretion of sodium. Various natriuretic peptides were isolated and synthetized, and the effects were investigated by many workers. Most studies, however, have been carried out under anesthesia and there have teen some controversies over direct effect of the factor on the renal function. Therefore, it was attempted in this study to access the effects of an atrial extract and a synthetic natriuretic factor in unanesthetized rabbits. Intrarenal arterial infusion of atrial extract caused a rapid increase of urinary volume and excretion of sodium. Glomerular filtration rate and renal plasma flow were both increased with no change in filtration fraction. The ventricular extract produced no change in urinary excretion of electrolytes, nor in renal hemodynamics. Intrarenal infusion of synthetic atrial natriuretic factor caused increases of renal excretory rate of sodium, chloride and potassium, and $FE_{Na}$. Glomerular filtration rate, renal plasma flow increased. And free water clearance also increased. Accentuated excretory function correlated well with increased glomerular filtration rate and renal plasma flow during infusion and for 10 minutes following the cessation of the infusion. Renin secretion rate decreased during constant infusion of atrial natriuretic factor. However, no correlation was found with the changes in glomerular filtration rate, renal plasma flow, or urinary excretion of sodium. These results suggest that atrial extract or atrial natriuretic factor induces changes in renal hemodynamics, as in excretion of electrolytes either indirectly through hemodynamic changes or directly by inhibiting tubular reabsorption. At the same time, renin secretory function is affected by the factor possibly through an unknown mechanism.

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산소 플라즈마로 표면처리된 탄소섬유/에폭시 적층복합재의 전단거동 (Shear Behavior of Plasma-treated Graphite/Epoxy Laminated Composites Using Oxygen Gas)

  • 김민호;이경엽;백영남;정동호;김현주
    • 한국정밀공학회지
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    • 제25권9호
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    • pp.103-108
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    • 2008
  • In-plane shear tests were performed to investigate the shear property change of FRP by plasma modification. Graphite/epoxy prepreg was used as a test material and plasma source was a microwave (2.4GHz) type. Plasma was induced by oxygen gas and its flow rate was kept $4{\sim}5$sccm with low vacuum state of $10^{-3}$ Torr. Prepreg was stacked unidirectionally ($[0^0]_8$) after plasma modification. Wettability was determined by measuring a contact angle. The results showed that the contact angle was decreased from $86^0$ to $45^0$ after plasma modification. Shear strength was also improved by ${\sim}10%$. SEM examination was made on the fracture surface and functional group produced by the plasma modification was investigated by XPS.

정적 연소기내의 스월 속도 변화에 따른 플라즈마 제트 점화의 연소특성 (Combustion Characteristicsof Plasma JetIgnition for Different Swirl Velocity in a Constant Volume Vessel)

  • 김문헌;박정서;이주환
    • 한국자동차공학회논문집
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    • 제9권2호
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    • pp.75-83
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    • 2001
  • This paper presents the evaluation of combustion characteristics of sing-hole plasma jet ignitions in comparison with conventional spark ignition for variable of swirl velocity. Plasma jet plugs are three types according to ejecting directions : center of chamber, positive and negative swirl flow direction. Experiments are carried out for equivalent ratio 1.0 of LPG-air mixture in a constant volume cylindrical vessel. Not only the flame propagation is photographed at intervals, but the pressure variation in the combustion chamber is also recorded throughout the entire combustion process. The results show that the plasma jet ignitions and spark ignition enhance the overall combustion rate by increasing the swirl velocity. The dependence of the combustion rate swirl velocity leade to the conclusion that the placma jet plug, which ejects plasma jet to the cwnter of combustion chamber is the most desirable ignitor than other plugs.

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헬리콘 플라즈마원의 특성 (Characterization of a Helicon Plasma Source)

  • 현준원;노승정;김경례;김창연;김현후
    • 한국표면공학회지
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    • 제32권6호
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    • pp.658-664
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    • 1999
  • Helicon sources are attractive for plasma processing because they provide high plasma density in low magnetic fields. Helicon waves were excited by a Nagoya type III antenna in a magnetized plasma column. Plasma parameters were measured with a double probe, and the structure and adsorption of the helicon wave fields were determined with the probes. Argon is fed through a MFC (mass flow controller) for operation pressure of 10~110 mtorr. A 13.56 MHz r.f. power of 50~450 W is induced through the antenna. The plasma density and electron temperature are measured as functions of external magnetic field, r.f. power and pressure. The plasma density as functions of r.f. power and magnetic field at a constant pressure increased linearly, and the electron temperature did not change largely with various operation parameters and the value was around 5~7 eV.

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분광학적 방법에 의한 Plasma Jet의 온도분석 측정 (Spectroscopic Measurement of Temperature Distribution in Some Plasma Jets)

  • 전춘생;박용관;임명선
    • 전기의세계
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    • 제26권2호
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    • pp.104-110
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    • 1977
  • This paper investigates temperature distribution of plasma jets which used argon gas, and nitrogen gas mixed with argon as working fluids in spectroscopic method, and studies correlations between them main results are as follows; 1) The temperature at the center of plasma jet increases with are current and gas flow, and decreases with magnetic flux density along the axial direction. 2) The changing rate of temperature of plasma jet in the radial direction decreases rapidly beyond 2mm from central axis. 3) Temperature drop rate of plasma jet in the central axis direction appears most apparant beyond 13mm above the nozzle exit. 4) When argon gas mixed with a small amount of nitrogen, plasma temperature increases at same are current compared with the case of argon gas only.

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