• Advances in nano research
• /
• v.17 no.1
• /
• pp.75-86
• /
• 2024

The insecticidal efficiency of orange (Citrus sinensis) peel essential oil (OP-EO) is limited because of its low stability under environmental conditions. Nanoemulsion formulations show promise in overcoming this limitation. Therefore, this study aimed to formulate and characterize the OP-EO nanoemulsion form (OP-EON) and investigate its insecticidal properties against two significant storage pests, Rhyzopertha dominica (Fabricius, 1792), and Tribolium castaneum (Herbst, 1797). The OP-EON (4:3:3:90 w/w, EO: Tween 80: Ethanol: water) was successfully created using an ultrasonic homogenizer. The major chemical components of the OP-EO were determined to be D-limonene (87.93%), myrcene (3.62%), and α-pinene (1.34%) through GC-MS analysis. The OP-EON was characterized using TEM (50-100 nm), Zeta sizer (the mean droplet particle size of 58.60 nm, the ζ-potential value of -12.6 mV, and the polydispersity index of 0.486), and FT-IR analysis. After 7 days, exposure to 500 ppm of the OP-EON resulted in 50% and 30% mortality rates in R. dominica and T. castaneum, respectively. Exposure to 1000 ppm of OP-EON resulted in 90% and 55% mortality in R. dominica and T. castaneum, respectively, after 7 days. Overall, these results clearly showed the potential to exceed the limits of the insecticidal activity of the OP-EO with its nanoemulsion form.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.12 no.1
• /
• pp.75-87
• /
• 2012

A design paradigm using sequential geometric programming is presented to accurately design CMOS op amps with BSIM3. It is based on new adaptive modeling of transistor parameters through the operating point simulation. This has low modeling cost as well as great simplicity and high accuracy. The short-channel dc, high-frequency small-signal, and short-channel noise models are used to characterize the physical behavior of submicron devices. For low-power and low-voltage design, this paradigm is extended to op amps operating in the subthreshold region. Since the biasing and modeling errors are less than 0.25%, the characteristics of the op amps well match simulation results. In addition, small dependency of design results on initial values indicates that a designed op amp may be close to the global optimum. Finally, the design paradigm is illustrated by optimizing CMOS op amps with accurate transfer function.

• Proceedings of the KIEE Conference
• /
• 1987.07b
• /
• pp.1521-1524
• /
• 1987

The performance of SCF can be improved with the Op-AMP which has the properties of high speed, large slew rate, and lower power dissipation. The OP-AMP used for SCF will be presented. For illustration, using this OP-AMP 5-th order LPF is designed.

• Food Science of Animal Resources
• /
• v.20 no.2
• /
• pp.93-100
• /
• 2000

Effects of onion peel (OP) components (quercetin and rutin) in press ham on TBARS, pH, redness (a*) and flavor (panel test) were investigated during cold storage. TBARS in OP samples of high concentration was significantly (P〈0.05) lower than control during cold storage. This result suggests that OP components have an antioxidant activity in press ham. Also, redness of OP samples was significantly (P〈0.05) higher than control after three weeks of cold storage. Cured ham redness could be improved through lower pH of OP samples compared to that of control. However, flavor score of OP samples was not significantly (P〉0.05) different with control during cold storage. It could be possible that OP components plays role as an antioxidant without any negative effects on plavor of press ham.

• Journal of Preventive Medicine and Public Health
• /
• v.25 no.2 s.38
• /
• pp.180-188
• /
• 1992

The effects of multiple exposures to pesticides on plasma cholinesterase(ChE) activities and urinary p-nitrophenol excretion were evaluated in rats. Rats were received single dose i.p. with $LD_{50}/100(mg/kg)$ of organophosphorous(OP), organophosphorous-organochroline(OP-OC), organophosphorous-carbamate(OP-CAB), organophosphorous-organoarsenate(OP-OA) pesticides for 4 consecutive days. In repeated administration of pesticides, plasma ChE activities were decreased, but urinary p-nitrophenol were increased after the first injection and then decreased gradually The recovery rates of ChE activities and p-nitrophenol excretion at 48 hours after the fourth Injection were delayed in comparision with the baseline value of 24 hours before the first injection. Statistical significances were found between OP and other groups except OP-OA group after the second injection in plasma ChE activities, but in urinary p-nitrophenol excretion there was statistical significance only between OP and OP-CAB.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.26 no.2
• /
• pp.118-123
• /
• 1989

In this paper, as we have integrated SCF for voice signal processing using CMOS circuit with the low power dissipation and the easy circuit design, it has been presented the simplified CMOS OP AMP design method with ${\pm}$5V pwoer source in order to use together with digital part. After an example about SCF CMOS OP AMP design, it has been performed layout appling channel width and length obtained by design method, and then its characteristics were simulated by SPICE 2G program. Therefoe, this design method will be applied the general CMOS OP AMP design in the electronic circuit.

• Environmental Mutagens and Carcinogens
• /
• v.21 no.2
• /
• pp.122-127
• /
• 2001

4-tert-octylphenol (OP) is a surfactant additive widely used in the manufacture of a variety of detergents and plastic products. Also, OP is known to have estrogenic activity by interacting with development and functions of endocrine system. This study was carried out to obtain toxicokinetic parameters of OP in male Sprague-Dawley rats. Male rats were administered OP, by either single oral (gavage) applications of 50, 100 or 200 mg/kg body weight. or a single intravenous injections of 1, 5 or 10 mg/kg body weight. Blood samples taken at several time intervals after administration were obtained from the femoral artery. Analysis of blood samples for OP was performed by gas chromatography mass spectrometry (GC/MS). The detection limit of OP was 1.9 ng/$m\ell$ at SIM (selected ion monitoring) mode of GC/MS. Calibration curve for analysis of the concentrations of OP in plasma was (OP/butylphenol peak area ratio) = 0.0294 $\times$ (plasma cone.) + 0.028 ($r^2$= 0.9991). The OP plasma concentration was 3921 ng/$m\ell$ immediately after single intravenous application, decreased rapidly within 45 min, and was detectable at low concentration up to 6 hr after application. When administered orally in rats (50, 100 and 200 mg/kg), OP was detected in the blood early after gavage administration, indicating the rapid initial uptake from gastrointestinal tract, with Tmax obtained from 0.67~0.83 hr. Using the AUC (area under the curve) of plasma concentration vs. time, low oral bioavailabilities of 1.2, 5.0 and 5.3% were calculated for the 50, 100 and 200 mg/kg groups, respectively.

• Biomedical Science Letters
• /
• v.16 no.4
• /
• pp.247-258
• /
• 2010

The objective of this research was to evaluate the relationships of preoperative (Pre-OP) levels of hematological and biochemical indices to perioperative variables in patients that underwent coronary artery bypass graft surgery (CABG). Pre-OP levels of hematological factors [total white blood cells (T-WBC), erythrocytes, hemoglobin, hematocrit, glycohemoglobin A1c (HbA1c), or platelet] were negatively or positively related with biochemical indices [alanine aminotransferase (ALT), bilirubin, glucose, fructosamine, triglyceride, and high density lipoprotein cholesterol (HDL)]. Pre-OP levels of hematological factors and biochemical indices were negatively or positively correlated with echocardiographic variables. Pre-OP level of HbA1c had a relationship with C-reactive protein. Pre-OP levels of aspartate aminotransferase (AST), ALT, HDL, glucose, fructosamine, or blood urea nitrogen (BUN) were positively or negatively associated with Pre-OP levels of cardiac markers (brain natriuretic peptide, troponin-I, creatine kinase isoenzyme 2, or CRP). Pre-OP levels of hematological factors (excepting T-WBC) related with operation time (OPT), postoperative mechanical ventilation time (POMVT), intensive care unit-period (ICU-period) or hospitalization. Pre-OP levels of AST, ALT, bilirubin, triglyceride, HDL, low dwensity lipoprotein, fructosamine, or BUN were positively or negatively correlated with OPT, graft numbers, POMVT, ICU-period or hospitalization. Retrospective this study reveals that Pre-OP levels of hematological and biochemical markers are associated with echocardiographic variables, several cardiac markers and postoperative outcomes, suggesting that Pre-OP levels of hematological and biochemical markers may be useful predictors for the diagnosis and prognosis of coronary artery disease.

• Journal of the Korean Society of Radiology
• /
• v.11 no.3
• /
• pp.101-108
• /
• 2017

DC/DC switching power converters are commonly used to generate a regulated DC output voltage with high efficiency. The advanced DC/DC converter uses a PWM-IC with OP-Amp. (Operational Amplifier) to control a MOSFET (metal-oxide semiconductor field effect transistor), which is a switching component, efficiently. In this paper, it is shown that the electrical characteristics of OP-Amp. are affected by radiations of ${\gamma}$ rays using $^{60}Co$ for TID (Total Ionizing Dose) testing and 5 heavy ions for SEL (Single Event Latch-up) testing. TID testing on OP-Amp. is accomplished up to the total dose of 30 krad, and the cross section($cm^2$) versus LET($MeV/mg/cm^2$) in the OP-Amp. operation is evaluated SEL testing after implementation of the controller board.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.44 no.10
• /
• pp.61-66
• /
• 2007

A gain enhancement rail-to-rail buffer amplifier for liquid crystal display (LCD) source driver is proposed. An op-amp with extremely high gain is needed to decrease the offset voltage of the buffer amplifier. Cascoded floating current source and class-AB control block in the op-amp achieve a high voltage gain by reducing the channel length modulation effect in high voltage technologies. HSPICE simulation in $1\;{\mu}V$ 15 V CMOS process demonstrates that voltage gain is increased by 30 dB. The offset voltage is improved from 6.84 mV to $400\;{\mu}V$. Proposed op-amp is fabricated in an LCD source driver IC and overall system offset voltage is decreased by 2 mV.