• Journal of Korean Academy of Nursing
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• 제25권1호
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• pp.88-98
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• 1995

The Fluid and electrolytes balance in the body is of critical importance in maintaining good health. When the fluid and electrolyte imbalance is present, patients are in great danger. They must be assessed immediately by a nurse so that appropriate treatment can be started as soon as possible. Patients' fluid intake and output records contain highly important information for the diagnosis and treatment of fluid imbalance, but, these records are often inaccurate and the method of recording the fluid intake is not universal for every hospital. Be-cause they are few quantitative measurements of a patient's hydration, the need to improve the accuracy of fluid intake records is very important. However, very few studies have been done to investigate the accuracy of measurements of patients' fluid intake and output. The purpose of this study was to investigate the methods used for calculation of fluid intake which is most similar to fluid output in normal adults and hospitalized patients. This study focused on three different calculation methods for fluid intake and compared these to fluid output and developed suggestions as to the ideal way to record fluid in-take. Data for 43 hospitalized patients and 37 normal adults were analyzed. The findings of this study are as follows ; 1) In normal adults, the daily intake of water which enteres by the oral route was 2415m1 (the first method of calculation). The daily intake of water in the form of pure water or some other beverage was 1365m1 (the third method of calculation) The daily intake of water including fresh fruits and vegetables, rice, porridges, and Me m which have water content more than 80% were 2186m1 (the second method of calculation). 2) The urine output of the normal adults was 1350m1. This apprroximates the amount of fluid an adult takes in the form of pure water. 3) In patient group, the total intake of water was 2550m1 (the first method of calculation). The in-take of water in the form of pure water or as some other beverage and IV fluid was 1661m1 (the third method of calculation). The daily in-take of water including foods which have high water content was 2356m1 (the second method of calculation). 4) The urine output of the patient's group was 1728m1. This approximates the amount of fluid an adult takes in the form of pure water. 5) Investigation of the method of calculation of the patient fluid intake showed that among the 31 hospitals studied, only eight use the third method of calculation which reflects the most close value to urine output. From the results obtained in this study, it was indicated that the amount of fluid taken in the form of pure water reflects the most close value to urine output. Therefore, it can be suggested that the third method of calculation which includes water in-take only in the form of pure water or beverage should be used as patients' fluid intake record.

• Journal of Korean Academy of Nursing
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• 제42권3호
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• pp.443-451
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• 2012

Purpose: This study was done to compare the rates of hemolysis and repeated sampling in blood samples obtained by a syringe needle versus a vacuum tube needle. Methods: A randomized, prospective study was used to evaluate the differences between the two blood sampling methods. The study group consisted of patients seen in the emergency department (ED) for blood sampling to determine electrolyte level. ED patients were randomly assigned to either the syringe group or the vacuum tube group. All blood samples were collected by experienced ED nurses and hemolysis was determined by experienced laboratory technologists. Data were analyzed using Fisher's exact test and binary logistic regression. Results: One hundred forty-five valid samples were collected (74 in the syringe group versus 71 in the vacuum tube group). 5 of 74 (6.8%) blood samples in the syringe group and 8 of 71 (11.3%) in the vacuum tube group hemolyzed. Repeated blood sampling occurred for 2 of 74 (2.7%) and 3 of 71 (4.2%) in each group respectively. There were no significant differences in rates of hemolysis and repeated sampling between two groups (B=1.97, p=.204; B=2.36, p=.345). Conclusion: Venipuncture with syringe needles can be recommended for ED nurses to obtain blood samples.

• Journal of the Korean Ceramic Society
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• 제41권6호
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• pp.456-463
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• 2004

To enhance the performance of anode-supported SOFC, single cell fabrication procedure was changed for better and resulting power generating characteristics of single cell were investigated. Liquid condensation process was employed for the granulation of NiO/YSZ powder mixture and the produced powder granules were compacted into anode green substrate by uni-axial pressing. YSZ electrolyte was printed on green substrate via screen-printing method and co-fired at 1400$^{\circ}C$ for 3 h. LSM/YSZ composite cathode of which the composition and heat treatment condition was adjusted to minimize the polarization#resistance with AC-impedance spectroscopy, was screen printed. The final single cell size from this multi-step procedure was 5${\times}$5 $\textrm{cm}^2$ and 10${\times}$10 $\textrm{cm}^2$. The maximum power densities of 5${\times}$5 and 10${\times}$10 single cells were about 0.45 W/$\textrm{cm}^2$ and 0.22 W/$\textrm{cm}^2$ at 800$^{\circ}C$, which are two times superior than those from single cells fabricated by the conventional process in previous our work.

• Journal of the Korean Electrochemical Society
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• 제5권1호
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• pp.21-26
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• 2002

A supercapacitor was developed using an amorphous ruthenium oxide material. The electrode of supercapacitor was prepared using an amorphous ruthenium oxide, which was synthesized from ruthenium trichloide hydrate$(RuCl_3{\cdo5}xH_2O)$. Thin film of tantalum was used as a current collector because it had wide. potential window characteristics than titanium and 575304 materials. A supercapacitor was assembled with ruthenium oxide as an electrode active material and 4.8M sulfuric acid solution as an electrolyte. The specific capacitance of the electrode was tested by a cyclic voltammetry using a half cell. The maximum differential specific capacitances during the oxidative and the reductive scans were 710 and $645\;F/g-RuO_2{\cdot}nH_2O$, respectively. The average specific capacitance was $521\;F/g-RuO_2{\cdot}nH_2O$. The assembled supercapacitor was protonated to the potential level of 0.5V vs. SCE. Super-capacitor, which was adjusted to the appropriate protonation level, had the specific capacitance of $151\;F/g-RuO_2{\cdot}nH_2O$ based on the concept of full cell.

• Journal of the Korean Electrochemical Society
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• 제3권1호
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• pp.44-48
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• 2000

Amorphous $V_2O_5$ cathode thin films were prepared by DC-magnetron sputtering at room temperature and the thin film rechargeable lithium batteries were fabricated with the configuration of $V_2O_5/LIPON/Li$ using sequential ex-situ thin film deposition techniques. The electrochemical characteristics of $V_2O_5$ cathode materials Prepared at 80/20 of $Ar/O_2$ ratio showed high capacity and cycling behaviors by half cell test. LIPON solid electrolytes films were prepared by RF-magnetron sputtering using the self-made $Li_3PO_4$ target in pure $N_2$ atmosphere, and it was very stable for lithium contact in the range of 1.2-4.0 V vs. Li. Metallic lithium were deposited on LIPON electrolyte by thermal evaporation methode in dry room. Vanadium oxide based full cell system showed the initial discharge capacity of $150{\mu}A/cm^2{\mu}m$ in the range of $1.2\~3.5V$.

• Journal of the Korean Electrochemical Society
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• 제6권2호
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• pp.145-152
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• 2003

Capacitance of a hybrid capacitor that has characteristics of both electrolyte capacitor and supercapacitor is determined by anode surface covered with oxide layer. In this study, optimal condition processes for anode to fabricate a high voltage hybrid capacitor was investigated. We mixed aluminum powder having mean particle size of $40{\mu}m$ with NaCl powders at weight ratio of 4 : 1 and prepared a disk type electrode after annealing at various temperature. After dissolving NaCl in $50^{\circ}C$ distilled water, heat treatment, eletropolishing, chemical treatment, and the first and the second etching of Al disk were conducted. In each process, capacitances and resistances of the disk measured by ac-impedance analyzer were compared to find its optimum treatment condition. Also, the surface morphology of treated disks were observed and compared by SEM. After the second etching, the Al disk was anodized at 365V to make an anode of hybrid supercapacitor that can be operated at 300V, Capacitance and resistance of the anodized Al disk electrode was compared with those of commercialized conventional aluminum electrolytic capacitor at different frequencies.

• Journal of the Korean Electrochemical Society
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• 제15권2호
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• pp.95-100
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• 2012

$LiFePO_4$ is an attractive cathode material due to its low cost, good cyclability and safety. But it has low ionic conductivity and working voltage impose a limitation on its application for commercial products. In order to solve these problems, the iron($Fe^{2+}$)site in $LiFePO_4$ can be substituted with other transition metal ions such as $Mn^{2+}$ in pursuance of increase the working voltage. Also, reducing the size of electrode materials to nanometer scale can improve the power density because of a larger electrode-electrolyte contact area and shorter diffusion lengths for Li ions in crystals. Therefore, we chose electrospinning as a general method to prepare $Li[Fe_{0.9}Mn_{0.1}]PO_4$ to increase the surface area. Also, there have been very a few reports on the synthesis of cathode materials by electrospinning method for Lithium ion batteries. The morphology and nanostructure of the obtained $Li[Fe_{0.9}Mn_{0.1}]PO_4$ nanofibers were characterized using scanning electron microscopy(SEM). X-ray diffraction(XRD) measurements were also carried out in order to determine the structure of $Li[Fe_{0.9}Mn_{0.1}]PO_4$ nanofibers. Electrochemical properties of $Li[Fe_{0.9}Mn_{0.1}]PO_4$ were investigated with charge/discharge measurements, electrochemical impedance spectroscopy measurements(EIS).

• Transactions of the Korean hydrogen and new energy society
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• 제24권3호
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• pp.223-229
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• 2013

Polymer Electrolyte Membrane Fuel Cell (PEMFC) is a power generation system to convert chemical energy of fuels and oxidants to electricity directly by electrochemical reactions. As a catalyst support for PEMFCs, carbon black has been generally used due to its large surface area and high electrical conductivity. However, under certain circumstances (start up/shut down, fuel starvation, ice formation etc.), carbon supports are subjected to serve corrosion in the presence of water. Therefore, it would be desirable to switch carbon supports to corrosion-resistive support materials such as metal oxide. $TiO_2$ has been attractive as a support with its stability in fuel cell operation atmosphere, low cost, commercial availability, and the ease to control size and structure. However, low electrical conductivity of $TiO_2$ still inhibits its application to catalyst support for PEMFCs. In this paper, to explore feasibility of $TiO_2$ as a catalyst support for PEMFCs, $TiO_2$ nanofibers were synthesized by electrospinning and calcinated at 600, 700, 800 and $900^{\circ}C$. Effects of calcination temperature on crystal structure and electrical conductivity of electrospun $TiO_2$ nanofibers were examined. Electrical conductivity of $TiO_2$ nanofibers increased significantly with increasing calcination temperature from $600^{\circ}C$ to $700^{\circ}C$ and then increased gradually with increasing the calcination temperature from $700^{\circ}C$ to $900^{\circ}C$. It was revealed that the remarkable increase in electrical conductivity could be attributed to phase transition of $TiO_2$ nanofibers from anatase to rutile at the temperature range from $600^{\circ}C$ to $700^{\circ}C$.

• Journal of Energy Engineering
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• 제5권2호
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• pp.108-114
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• 1996

It is one of the most important factors to enhance the efficiency of the solar collectors by in-creasing collecting efficiency and decreasing heat loss. The pulse electrodeposition method has been involved in this study to improve characteristics of the solar selective coating on 230cm${\times}$60cm substrates and electrical efficiency of the process. The composition of the electrolyte was 280 g/$\ell$ chromic acid, 15 g/$\ell$ propionic acid, and 10 g/$\ell$ appropriate additive. 230cm${\times}$60cm copper and aluminium sheets were utilized as the substrates. It has been observed that the black chrome coatings exhibited reasonable optical properties for commercialization when the plating parameters were properly controlled; the absorptance was 0.98 and 0.97 and omittance was 0.17 and 0.23 for copper and aluminium substrate, respectively. This study implies that the pulse current electrolysis method could be applied to the large scale substrates, and the various products can be avilable after the consideration of the thermal conductivity, heat transfer efficiency and cost problems of the substrates.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제47권5호
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• pp.361-367
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• 2002

In order to determine the optimum harvest time for the seed production of inbreds and hybrids in silage corn, the ears of sib-pollinated 'KS5', 'KS7rhm', and 'Ga209' and cross-pollinated 'KS5' $\times$ 'KS6' (Suwon19), 'KS7 rhm' $\times$ 'KSl17' (Suwonok), and 'Ga209' $\times$ 'DB544'(Kwanganok) were harvested at the one-week intervals from 4 to 10 weeks after silking. The optimum harvest time for the seed production for 'KS5', 'KS5' $\times$ 'KS6', 'KS7 rhm', and 'KS7rhm' $\times$ 'KS117' was 7 weeks after silking considering both emergence rate and plumule growth in cold test. Although earlier harvested seeds showed similar germination rate as the seeds harvested at the optimum time at $25^{\circ}C$, their emergence rate were lower in cold test. Seed weight and $\alpha$-amylase activity of earlier harvested seeds were lower compared to those of seeds harvested at the optimum time, while leakage of total sugars and electrolytes were higher. However, the later harvested seeds showed lower germination rates at $25^{\circ}C$ and emergence rates in cold test probably due to the lower $\alpha$-amylase activity although they showed increased seed weight and reduced leakage of total sugars and electrolytes. In contrast, the emergence rate of 'Ga209' and 'Ga209' $\times$ 'DB544' in cold test increased up to 10 weeks after silking probably due to the increased seed weight and $\alpha$-amylase activity and reduced sugar and electrolyte leakages during the germination. The cross-pollinated F$_1$ hybrid seeds showed higher germination and emergence rates at $25^{\circ}C$ and in cold test, and higher plumule growth and $\alpha$-amylase activity compared to those of sib-pollinated inbreds.