• Journal of Preventive Medicine and Public Health
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• v.34 no.2
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• pp.127-130
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• 2001

Objective : To verify the separate and combined effects of cadmium and nickel on blood pressure in rats. Methods : Following the daily administration of cadmium chloride$(CdCl_2)$ and nickel chloride$(NiCl_2)$ to rats both individually and in combination with intraperitoneal injection method for one week, systolic blood pressure of the tail was measured at 1 day and 5, 10, 20, 30 days after administration. Each substance was injected into the rats with 0.1 mg/kg bw and 1.0 mg/kg bw concentration. Results : After 0.1 mg/kg bw $CdCl_2$ was injected, a statistically significant difference was found as compared with the control group(only saline) after 1, 5 and 10 days. After 0.1 mg/kg bw $NiCl_2$ was injected, a statistically significant difference was not found compared with the control group. After 0.1 mg/kg bw $CdCl_2$ and 0.1 mg/kg bw $NiCl_2$ were injected simultaneously, a statistically significant difference was found as compared with the control group after 1,5 and 10 days and compared with 0.1 mg/kg bw $CdCl_2$ group after 5 days and as compared with 0.1 mg/kg bw $NiCl_2$ group after 5 and 10 days. After 1.0 mg/kg bw $CdCl_2$ was injected, a statistically significant difference was found as compared with the control group after 1, 5, 10 and 20 days. After 1.0 mg/kg bw $NiCl_2$ was injected, a statistically significant difference was found as compared with the control group after 1 day and 5 days. After 1.0 mg/kg bw $CdCl_2$ and 1.0 mg/kg bw $NiCl_2$ were injected in combination, a statistically significant difference was found after 1, 5, 10, 20 and 30 days as compared with 1.0 mg/kg bw $CdCl_2$ after 10, 20 and 30 days and as compared with 1.0 mg/kg bw $NiCl_2$ after 5, 10, 20 and 30 days. Conclusion : It was found that the effect of $CdCl_2$ on blood pressure was much more than $NiCl_2$ and a high concentration $CdCl_2\;and\;NiCl_2$ in combination delayed the recovery of blood pressure.

• The Korean Journal of Pharmacology
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• v.27 no.1
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• pp.21-31
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• 1991

When administered intracerebroventricularly (icv), cholinergic nicotinic agents, nicotine and DMPP, as well as cholinergic muscarinic agents, muscarine and bethanechol, produced pressor responses in urethane-anesthetized vagotomized rabbits. The response patterns to nicotine and to DMPP were similar, while the bethanechol response resembled the muscarine pattern. The pressor response to nicotine and DMPP was markedly inhibited by icv mecamylamine but not by icv pirenzepine, whereas the response to muscarine and bethanechol was inhibited by icv pirenzepine but not by icv mecamylamine, suggesting that both nicotinic and muscarinic receptors in the brain are involved in the action. Intravenous pretreatments of animals with regitine, reserpine, enalapril, saralasin, both regitine and enalapril, both regitine and saralasin, SK&F-100273 did not prevent the pressor response to nicotine and muscarine. Iv pretreatments with both regitine and SK&F-100273 inhibited the nicotine response without affecting the muscarine response, whereas pretreatments with three agents, regitine, enalapril and SK&F-100273, inhibited the muscarine response. The nicotine-induced elevated blood pressure as well as the muscarine-induced were lowered by regitine but not by enalapril or by SK&F-100273. Enalapril was without effect on the nicotine hypertension in rabbits treated with regitine or both regitine and SK&F-100273, whereas SK&F-100273 lowered the nicotine hypertension in regitine-treated animals. Enalapril did not enhance the lowering effect of SK&F-100273 in regitine-treated ones, nor did it cause a fall of the muscarine hypertension induced in regitine-treated rabbits, but it did lower the blood pressure in animals treated with both regitine and SK&F-100273. Likewise, SK&F-100273 did not cause a fall of the muscarine hypertension induced in regitine-treated rabbits, but it did lower the blood pressure in animals treated with both regitine and enalapril. These data suggest that the nicotine-induced hypertensive state is related to at least two systems in the periphery-sympathetic and vasopressin, whereas in the muscarine-induced hypertensive state three systems in the periphery are involved, i.e., the sympathetic, vasopressin and angiotensin system. The hypotensive effect of regitine on basal arterial blood pressure levels of rabbits was not influenced by pretreatment with either of enalapril or SK&F-100273, but significantly potentiated by treating with both enalapril and SK&F-100273, suggesting participation of the sympathetic and the renin-angiotensin system as well as the vasopressin system in maintenance of arterial blood pressure.

• Journal of Veterinary Clinics
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• v.18 no.3
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• pp.249-256
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• 2001

This study was performed to evaluate cardiopulmonary depressant effects of enflurane (1.0 vol%) combined with propofol(0.25 mg/kg/min) compared with enflurane inhalation, and propofol infusion, respectively, in 18 healthy dogs premedicated with acepromazine and atropine. After bolus injection of propofol 5 mg/kg for induction and tracheal intubation, they were randomly assigned to 3 groups: propofol 0.5 mg/kg/min infusion (Group I, n=6), enflurane 2.5 vol% (Group II, n=6) and enflurane 1.0 vol% combined with propofol 0.25 mg/kg/min (Group III, n=6). Mean arterial Pressure (MAP), systolic arterial pressure (SAP) and diastolic arterial pressure (DAP) were depressed significantly in all groups, especially in Group II. MAP, SAP and DAP values of Group IIIwere higher than those of Group II, but lower than those of Group I. The changes of PaO$_2$, Pa$CO_2$and pHa were similar in all groups. Respiration rates were decreased in all groups 5 minutes after induction but maintained in normal range. Those of Group I were less depressant than those of Group II and Group III. Concentrations of $Na^+ and Cl^-$ were increased and those of $K^+$ were decreased in all groups, but their values were quitely similar. Heart rate was changed in small range and the value of Group I was higher than those of Group II and Group III. Body temperature was decreased significantly in all groups. Adverse effects like as muscle rigidity, nausea or vomiting and shivering were not appeared and apnea at induction was occured 6 dogs. From the these results, enflurane 1.0 vol% combined with propofol 0.25 mg/kg/min also could be applied for anesthesia in dogs.

• Journal of Korean Medicine Rehabilitation
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• v.15 no.1
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• pp.127-141
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• 2005

Objectives : This study was performed to investigate the effects of Gamichangbaek-san(Jiaweichangbai-san) on anti-inflammatory, analgesic, anti-febrile and immune response on the arthritis of carrageenan-induced animals. Methods and Materials : Rats were classified into control and sample groups which are 7 individuals each for the experiments about anti-inflammatory and anti-febrile. Each of the 7 mice were classified into normal, control, sample groups for the analgesic experiments. Gamichangbai-san(Jiaweichangbai-san) was administered to sample group and normal saline was administered to normal and control groups. Arthritis was induced by injection of 1% carrageenan $0.1m{\ell}$ and Gamichangbaek-san(Jiaweichangbai-san) was administered after 30 minutes. The change of edema in Carrageenan-induced Arthritic Rats' Paws was measured after 1 hour and 5 hours from the injection of carraqeenan with Plethysmometer(7150, UGO BASILE, ltaly) by Winter' method. WBC, Lymphocyte and ESR were measured by heart puncture and CD4+ T cell, CD8+ T cell and CD4+/CD8+ T cell ratio were measured from the spleen tissue. Writhing syndrom was measured with Tail flick unit(UGO BASILE, Italy) in the experiments conducted to check the analgesic activity. The temperature of the paws of carrageenan-induced arthritic rats was measured by Laser thermometer. Rectal temperature was measured by Yeast's method in anti-febrile experiments. Immune response was measured by CD4+, CD8+ T cell ratio and CD4+/CD8+ T cell ratio. Results : 1. It was recognized that Gamichangbaek-san(Jiaweichangbai-san) decreased the increase rate of Paw Edema effectively with statistical significance. 2. It was recognized that Gamichangbaek-san(Jiaweichangbai-san) decreased WBC, Lymphocyte and ESR with statistically high significance. 3. It was recognized that Gamichangbaek-san(Jiaweichangbai-san) did not show significant analgesic effect, but the Pressure pain threshold of the paws was increased with statistical significance. 4. It was recognized that Gamichangbaek-san(Jiaweichangbai-san) decreased rectal temperature effectively and had an anti-febrile effect about the febrile of a joint with statistical significance. 5. It was recognized that Gamichangbaek-san(Jiaweichangbai-san) increased CD4+ T cell ratio with statistically high significance and increased CD+8 T cell ratio with statistical non significance but increased CD4+/CD8+ T cell ratio effectively with statistical significance, too. Conclusions : According to the above results, it can be concluded Gamichangbaek-san(Jiaweichangbai-san) showed the treatment effects on the artificial arthritis resulted from carageenan in rats and it is suggested that more interest and study in the security for the clinical use were needed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.9
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• pp.909-916
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• 2015

In this study, to investigate the effect of spray behavior characteristics, we induce the mixing ratio of emulsified fuel using impinging spray. We formulate the emulsified fuel by mixing diesel and hydrogen peroxide($H_2O_2$). We set the temperature of the heating plate to $150^{\circ}C$, $200^{\circ}C$, and $250^{\circ}C$, and set the injection pressures to 400, 600, 800, and 1000bar. The surfactants for the emulsified fuel mixture, which were mixed span80 and tween80 was mixed as 9:1, were fixed to 3% of the total volume of the emulsified fuel. We set the mixing ratio of $H_2O_2$ in the emulsified fuel as emulsified fuel(EF)0, EF2, EF12, and EF22. Further, we visualize the evaporation impinging spray using the Schlieren method. Based on the results of this study, we found that a higher temperature and injection pressure of the heating plate impingement led to the active diffusion of the fuel vapor, which promoted emulsified fuel evaporation. When the emulsified fuel is utilized in an actual engine, because of the temperature-drop effect of the combustion chamber, which is due to the evaporation of $H_2O_2$ in fuel and faster mixture formation is expected to decrease the engine emissions.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.1
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• pp.107-112
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• 1999

The ZnSe/GaAs epilayers were grown by RF reactive sputtering. In order to obtain the optimum condition of the growth, we have studied the dependence of Ar pressure, input power of sputter, temperature of substrate, and the distande between substrate and target. Through the observation of the grown epilayer via electronic microscope, we confirmed that the layer's surface was uniform and the boundary of the substrate and the layer was well defined. The defotmation of lattice distortion and the distortion ratio were obtained by DCRC measurements. From mrasurements of photoluminescence, in the ZnSe/GaAs sample without injection of $N_2$gas, we found that the intensity of bound exciton $I_2$is stronger than that of $I_1$and the bound exiton $I_1$represents the deep acceptor level, $I_1\;^d$. On the other hand, in the ZnSe/GaAs sample with injection of$N_2$gas, the peak of$I_1$ was much higher than that of the $I_2$and the half width appeared to be narrow. We concluded that the p-type of ZnSe/GaAs epilayer was grown successfully, because of stronger peak of the bound exciton $I_1$due to the $N_2$dopping.

• Analytical Science and Technology
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• v.25 no.6
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• pp.382-387
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• 2012

Ethylene oxide ($C_2H_4O$, EtO) is used as a raw material for the production of ethylene glycol and other industrially important material such as ethanolamines and also used as a disinfecting agent. It is applied for gas-phase sterilization of thermally sensitive medical equipment, and for processing of storage facilities as a mixture with fluorinated hydrocarbon. In this perspective, accurate determination of the mole fractions of components in the liquefied gas mixture is required for the quality control and safety of production and use. Each component of the liquefied gas mixture has different chemical and physical properties such as vapor pressure and boiling point. Therefore, we can suppose that analytical results can be different according to the introduction method for the gas phase of upper layer, or for the liquid phase of lower layer in gas cylinder. In this study, we designed a new on-line sample injection device for the liquefied gas mixture in liquid or gas state, and applied to the analysis of liquefied gas mixture of ethylene oxide and fluorinated hydrocarbons by GC/AED (gas chromatograph-atomic emission detector). We studied performance of AED, and effect of sample introduction and selected wavelength to the accuracy and repeatability of analytical results.

• Tunnel and Underground Space
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• v.25 no.4
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• pp.320-331
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• 2015

This paper presents a case study of an enhanced geothermal system(EGS) demonstration project conducted in $Gro{\ss}$ $Sch{\ddot{o}}nebeck$, Northerm Germany, focusing on hydraulic stimulation. The project was conducted with doublet system in sandstone and volcanic formations at 4 - 4.4 km depth. Under normal faulting to strike-slip faulting stress regime, hydraulic stimulations were conducted at injection and production wells by massive waterfrac and gel-proppant fracturing. Injectivity index increased from $0.97m^3/(hr^*MPa)$ to $7.5m^3/(hr^*MPa)$ and productivity index increased from $2.4m^3/(hr^*MPa)$ to $10.1m^3/(hr^*MPa)$ by a series of hydraulic stimulations at both wells. After circulation tests through injection and production wells, however, productivity index decreased from $8.9m^3/(hr^*MPa)$ to $0.6m^3/(hr^*MPa)$ in two years. Slip tendency analysis for the stimulation in volcanic layer estimated the required pressure for shear slip and its preferred orientations and it showed reasonable match with actual stimulation results. Through the microseismicity observation for the stimulation of volcanic formation, only 80 seismic events with its moment magnitudes in -1.8<$M_W$<-1.0 were observed, which are unexpectedly low for EGS hydraulic stimulation.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.2
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• pp.129-137
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• 2014

In this study, the characteristics of exhaust gas as a function of the biodiesel mixing ratio were investigated. Diesel and waste oil were used for preparing mixed fuel, and the ratios of the mixed fuel were varied in the BD3~BD100 range. The injection pressures(${\Delta}p_{inj}$) was considered as an experimental variable and was set to 400 bar, 600 bar, 800 bar, 1000 bar, and 1200 bar. Furthermore, for quantitatively analyzing the characteristics of exhaust gas(NOx and Soot), the concepts of Pearson correlation coefficient and Spearman rank-order correlation coefficient based on statistics were introduced. Consequently, it was found that the correlation of the emission of NOx and Soot is linear, and the Pearson and Spearman coefficients are -0.732 and -0.724, respectively, under all analysis conditions. Especially, for the injection pressure of 800 bar, a simultaneous reduction in NOx and Soot emission is possible by controlling the biodiesel mixing ratio. This is because the correlation coefficients of NOx and Soot emissions were nearly 0, as the Pearson correlation coefficient was -0.089.

• Journal of Biosystems Engineering
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• v.6 no.2
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• pp.1-8
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• 1982

The objective of this study was to find out the technical feasibility of ethanol-diesel fuel blends as a diesel engine fuel. Fuel properties essential to the proper operation of a diesel engine were determined for blends containing several concentrations of ethanol in No. 2 diesel fuel. A single-cylinder diesel engine for a power tiller was used for the engine tests, in which load, speed and fuel consumption rate were measured. The fuels used in tests were No. 2 diesel fuel and a blend containing 10-percent ethanol and 90-percent No. 2 diesel fuel. The results of the study are summarized as follows. 1. It was not possible to blend ethanol and No. 2 diesel fuel as a homogeneous solution even though anhydrous ethanol was used. The problem of blending ethanol in No. 2 diesel fuel could be solved by adding butanol about 5% of the amount of ethanol in the blends. 2. Because ethanol had a much lower boiling point ($78.3^{\circ}C$ under atmospheric pressure) than a diesel fuel, it was necessary to store ethanol-diesel fuel blends airtight in order to prevent them from evaporation losses of ethanol. 3. The addition of ethanol to No. 2 diesel fuel lowered the fuel viscosity and the cetane rating, but a blend of 10% ethanol and 90% diesel fuel had a viscosity and a cetane rating well above the KS minimum values for No. 2 diesel fuel. 4. At the rated speed, the specific fuel consumption of No.2 diesel fuel was lower than that of the 10% ethanol blend for the almost entire range of load. However, under the overload condition the specific fuel consumption was lower for the 10% ethanol blend. 5. Under the variable-speed full-load tests, both fuels produced approximately the same torque and power. At the speeds of 1600rpm or below, the specific fuel consumption of No. 2 diesel fuel was lower than that of the 10% ethanol blend. At the speeds of 1600rpm or above, however, the specific fuel consumption was lower for the 10% ethanol blend. 6. At the ambient temperature above $15^{\circ}C$, the use of the 10% ethanol blend in the engine created a vapor lock in the fuel injection pump and stalled the engine. The vapor locking problem was overcome by chilling the surroundings of the fuel injection pump and the cylinder head with water.