• Preventive Nutrition and Food Science
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• 제4권1호
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• pp.79-83
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• 1999

A potentiometric biosensor employing a CO3-2 ion-selective electrode(ISE) and malic enzyme immobilization in al flow injection analysis (FIA) system was constructed. Analytical parameters were optimized for L-malate determination . The CO3-2 -ISE-FIA system was composed of a pump, an injector, a malic enzyme (EC1.1.1.40) reactor, a CO3-2 ion-selective electrode, a pH/mV meter and a recorder. Cofactor NADP was also injected with substrate for theenzyme reaction into the system. Optimized analytical parameters for L-malate determination in the CO3-2 ISE-FIA system were as follows ; flow rate, 14.5ml/hr ; sample injection volume, 100ul; enzyme loading in the reactor, 20 units ; length of the enzyme reactor , 7 cm ; tubing length form the enzyme reactor to the detector as a geometric factor in FIA, 15 cm . The response time for measuring the entire L-malate concentration range (10-2 ~10-5 mol/L ; 4 injections )was <15minutes . In this CO3-2 -ISE-FIA system, the potential differences due to th eformation of CO3-2 by the reaction of malic enzyme on L-malate were correlated to L-malate concentration in the range of 10-2 ~10-5mol/L ; the detection limit was 10-5 mol/L. This potentionmetric CO3-2 ISE--FIA system was found to be useful for L-malate measurement.

• 한국진공학회지
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• 제14권2호
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• pp.69-77
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• 2005

중성입자빔 가열장치의 이온원과 빔라인 부품들을 개발하고 시험하기 위해 제작한 부피 $60m^3$의 시험설비에는 특성 비교를 위해 몇 가지 다른 방식으로 제작된 대용량 크라이오 흡착펌프를 장착하여 사용하고 있다. 크라이오 펌프의 활성탄 패널을 냉각시키면서 수소를 적절한 간격으로 도입하여 수소 분압을 측정하고 그 시간적인 변화를 통해 온도에 따른 수소흡착과 방출특성을 분석해 보았으며 관련 파라미터 사이의 상호 영향에 대해 알아보기 위해 시뮬레이션을 수행했다.

• 공업화학
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• 제4권2호
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• pp.416-422
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• 1993

성능이 우수한 킬레이트막을 개발하고자 chitosan에 글루타르알데히드를 가교시켜 막을 제조하였으며, 이 막을 통한 금속 이온의 투과 특성을 조사하였다. 막을 통한 이온의 투과는 downstream 용액의 pH의 영향을 크게 받았으며, 이 현산에 대하여 proton pump 메카니즘을 제안하였다. 막 표면에서의 착물형상에 의한 선택흡착성이 선택투과성에 영향을 미친다고 생각되며, $Mg^{2+}$과 $Cu^{2+}$의 혼합 용액에서 $Cu^{2+}$의 선택도는 9.5이었다.

• 대한의용생체공학회:의공학회지
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• 제24권1호
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• pp.45-53
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• 2003

Based on the 4-compartmental pharmacokinetic model developed in PART1, target-controlled infusion(TCI) pump system was designed and evaluated. The TCI system consists of digital board including microcontroller and digital signal process(DSP), analog board, motor-driven actuator, user friendly interface, power management and controller. It provides two modes according to the drugs: plasma target concentration and effect target concentration. Anaesthetist controls the depth of anaesthesia for patients by adjusting the required concentration to maintain both plasma and effect site in drug concentration. The data estimated in DSP include infusion rate, initial load dose, and rotation number of motor encoder. During TCI operation, plasma concentration. effect site concentration, awaken concentration, context-sensitive decrement time and system error information are displayed in real time. Li-ion battery guarantees above 2 hours without power line failure. For high reliability of the system, two microprocessors were used to perform independent functions for both pharmacokinetic algorithm and motor control strategy.

• Childhood Kidney Diseases
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• 제14권2호
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• pp.120-131
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• 2010

Renal tubular acidosis (RTA) is a metabolic acidosis due to impaired excretion of hydrogen ion, or reabsorption of bicarbonate, or both by the kidney. These renal tubular abnormalities can occur as an inherited disease or can result from other disorders or toxins that affect the renal tubules. Disorders of bicarbonate reclamation by the proximal tubule are classified as proximal RTA, whereas disorders resulting from a primary defect in distal tubular net hydrogen secretion or from a reduced buffer trapping in the tubular lumen are called distal RTA. Hyperkalemic RTA may occur as a result of aldosterone deficiency or tubular insensitivity to its effects. The clinical classification of renal tubular acidosis has been correlated with our current physiological model of how the nephron excretes acid, and this has facilitated genetic studies that have identified mutations in several genes encoding acid and base ion transporters. Growth retardation is a consistent feature of RTA in infants. Identification and correction of acidosis are important in preventing symptoms and guide approved genetic counseling and testing.

• Preventive Nutrition and Food Science
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• 제3권1호
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• pp.36-42
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• 1998

Ion-selective eleltrodes(ISEs) are simple electrodechemical devices for the direct measurement of ions in the samples. A novel potentiometric biosensor for the determination of L-Malate or D-isocitrate has been developed by using CO2-3 -ISE-FIA system was composed of a pump, an injector, a malic enzyme or isocitric dehydrogenase enzyme reactor, a CO2-3 -ISE, a pH/mV meter, and an integrater. The various factors, such as buffer capacity types of plstericizer and polymer, were optimized for the CO2-3 selectivity. In this novel CO2-3 --ISE-FIA system, the potential difference due to the amount of CO2-3 produced from each enzyme reaction was proportional to the amount of L-malate or D-isocitrate.

• 한국광학회지
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• 제2권3호
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• pp.133-138
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• 1991

Eosin을 첨가한 boric acid 유리질 포화흡수체의 포화세기는 비교적 낮은 것으로(약 700 mW/$\textrm{cm}^2$) 측정되었고, 세기가 낮은 경우에서도 축퇴4광파혼합에 의해 광학적 위상공액파를 발생시킬 수 있었다. 파장이 488nm인 Ar-ion laser를 사용하여 이 매질에서 DFWM에 의한 위상공액파의 편광특성을 보였고, 위상공액 반사율의 빛의 세기와 파장에 대한 의존성을 측정하였다. 이 매질에서 비축퇴2광파혼합에 의한 에너지 교환은 두 광속의 주파수차가 약 100 Hz 정도인 경우에 최대가 되었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.69.2-69.2
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• 2015

가속기의 진공용기는 안지름이 대략 20~40 mm 정도로 아주 작지만 길이는 수백 미터 이상이다. 이 같은 진공장치에서 기체 컨덕턴스가 그 진공성능을 결정하게 되며 점점 더 작아지고 있다. 이때 진공배기 방법은 주로 균등배기(distributed pumping)을 하는 데 초기에는 distributed ion pump와 Strip NEG를 주로 사용하였으며 최근에는 coated NEG가 대세이다. 균등배기의 또 다른 한 가지 방법으로 작은 동전 모양의 게터를 사용하여 그 성능을 평가하여 보고하고자 한다.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2002년도 제9회 학술 발표회 프로그램과 논문초록
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• pp.9-11
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• 2002

Plasma membrane Na$^{＋}$-K$^{＋}$ ATPase (pump) is an essential component to maintain asymmetrical ion distribution across cell membrane. The Na$^{＋}$-K$^{＋}$ ATPase was discovered by Jens C. Skou in 1957 and since then physiological and biochemical properties of the enzyme have been extensively studied. Jens C. Skou was awarded the 1997 Nobel Prize in chemistry for his discovery of the Na $^{＋}$ - $K^{＋}$ ATPase.(omitted)

• Mass Spectrometry Letters
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• 제3권4호
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• pp.87-92
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• 2012

In this study, we explored a new approach for generating ions of organics and biomolecules using contactless atmospheric pressure ionization (C-API). That is, a tapered capillary (~20 cm) was connected to a syringe, which was coupled to a syringe pump for providing a given flow rate to introduce sample solution to the proximity of a mass spectrometer. The gas phase ions derived from analytes were readily formed in the capillary outlet, which was very close to the mass spectrometer (~1 mm). No external electric connection was applied on the capillary emitter. This setup is very simple, but it can function as an ion source. This approach can be readily used for the analysis of small molecules such as amino acids and large molecules such as peptides and proteins. The limit of the detection of this approach was estimated to be ~10 pM when using bradykinin as the sample. Thus, we believe that this approach should be very useful for being used as an alternative ion source because of its low cost, high sensitivity, simplicity, and ease of operation.