• Korean Journal of Crystallography
• /
• v.4 no.2
• /
• pp.54-62
• /
• 1993

The crystal shnture of dehydrated fully Cd2+-exchanged zeolite A evacuated at 2 × 10-6 Torr and 650℃ (a:12.189(2) A) and of its iodine sorption corrplex (a:12.168(2)A) have been netsmlmn by single uystal x-ray diffraction techliques in the cubic space group hkTn at 21(1)℃. The strutures were refined to final error indices, Ri:0.057 and R2 =0.063 with 186 reflections and Rl:0.082 and R2:0.085 with 181 reflections, respectively, for which 1>3σ(In both structure, six lie at two distinguished threefold axes of unit cell ten the crystal structure of an iodine sorption complex of Cd6-A four Cd2+ ions are recessed 0.69(1) A into the large cavity to complex each with from the (111) plane of 0(3), whereas two Cd2+ ions recessed 0.68(1) A into the sodalite unit Awximately 4.0 l3ions per nit cell are sorbed. Each bridge between a Cd2+ ion and 8-ring oxygens ((I-I-I)= 117(1) ˚ and 0(1)-I(1)-I(2)=172(1)). The near linear I-I-0 angle and its interatomic distance (I-0=3.57(3) A) are indicative of a weak charge transfer interacticn between the frarrework oxygen and iodine. The existence of In3 inside the large cavity indicates that the If ions and H ions may be produced by reaction of In vapor with water molecules which maybe associated with Cd2+ ions in partially dehydrated Cd6-A In3- ions may be produced by the combination of I- and I2.

• Journal of the Korean Chemical Society
• /
• v.9 no.3
• /
• pp.128-133
• /
• 1965

Hydrazonium diphosphate crystallizes with the space-group symmetry $P2_1/C.$ There are two formular units of $N_2H_6H_4(PO_4)_2$ in the unit cell, for which $a = 4.52{\pm}0.02, b = 8.06{\pm}0.03, c = 10.74{\pm}0.03{\AA}\;and\; {\beta} = 100{\pm}0.5^{\circ}.$ The determination of the crystal structure was carried out by means of Patterson, Fourier and difference syntheses. The phosphate group has configuration of nearly regular tetrahedron with the mean P-O distance of $1.55{\AA}.$ The N-N distance found is $1.40{\AA},$ which corresponds to previously reported values for the $N_2H_6^{++} \;ion \;in\; N_2H_6SO_4.$ A molecule has a transform with a center of symmetry in it. Each nitrogen atom forms three hydrogen bonds with the N…O distances 2.62, 2.79 and $2.89{\AA}.$ And a O…O hydrogen bond between different phosphate groups is found with the distance $2.63{\AA}.$ The structure is held together by three-dimensional network of the strong hydrogen bonds.

• Applied Microscopy
• /
• v.24 no.1
• /
• pp.28-40
• /
• 1994

Xerostomia and xerophthalmia are delicate or serous side effects, occuring when the radiotherapy is administered to the head and neck cancer patient. It is known that the cause of the above side effect is radiosensitivity of serous cells. In this study, the ultrastructural features of the parotid glands of the X-irradiated rats were observed. Sprague-Dawley rats weighing 200-250g each were anesthetized with sodium thiopental, and placed on the Mitsubishi linear accelerator. Only the head and neck areas of animals were exposured at the distance of 80cm, within the area of $30X30cm$, in the depth of 1cm, with the speed of 200R/min. Total doses applied were 3,000R or 6,000R depending on the experimental groups. Animals were sacrificed on the 6th hour, 2nd day and 6th day after the irradiation. Parotid glands were fixed in the 2.5% glutaraldehyde-1.5% paraformaldehyde solution, and followed by refixation in the 1% osmium tetroxide solution. Dehydrated blocks were embedded in araldite mixture, and ultrathin sections were cut. Sections were contrasted with the solution of uranyl acetate and lead citrate, and observed with JEM 100 CX-II electron microscope. The results were as follows: 1. Normal parotid acinar cells are two types; the light and the dark acinar cells. The light acinar cell contains dense secretory granules, whereas dark acinar cells contains granules of medium density with some darker spots within them, or other cells contain granules of medium density with darker rims. 2. Six hours after the irradiation, many acinar cells were degenerated showing variable stages of cytolytic bodies, light bodies, or dense degenerations. Within the acinar cell, Golgi apparatus and granular endoplasmic reticula were most severely altered elements. Granules showed more contrasting densities and irregularities. 3. Two days after the irradiation, some cytolytic bodies, and focal lucent degeneration of cytoplasm, and fine granular alteration of cytoplasmic matrix were pronounced. But other elements including secretory granules are rather looked unlatered. 4. Six days after the irradiation, most severe alterations were seen. Many intracellular canaliculi (or secretion figures), quanta of cytoplasm containing secretion antecedants, severely irregular luminal border, and again contrasting density of secretory granules showing tigroid spots or dense rims were noted. And myoepithelial degenerations were observed not uncommonly. 5. Irregular densities of secretory granules were interpreted as abnormal components of protein or carbohydrate portion are synthesized or abnormally metabolized under severe X-irradiation. 6. Myoepithelial degeneration and related alteration of nerve endings, etc., were suggested as the other causes of xerostomia following X-irradiation. 7. It is requested that radiation doses should be arranged, considering in mind not only the sensitivity of acinar cells but also the myoepithelial and neural functions.

• Journal of Institute of Control, Robotics and Systems
• /
• v.15 no.9
• /
• pp.877-880
• /
• 2009

A curing process in post-printing section of R2R process is required for an electrical property of the printed pattern when devices such as RFID, Solar cell are printed. PEN as well as heat-stabilized PET which is used as a plastic substrate would be deformed at high temperature due to change of its elastic modulus. And crack in the printed pattern, which is on the plastic substrate is occurred due to the deformation of the substrate. The occurrence of crack causes electrical resistance to increase and the quality of the device to deteriorate. In case of RFID antenna, the range of reading distance is shortened as the electrical resistance of the antenna is increased. Therefore, the deformation of the plastic substrate, which causes the occurrence of crack, should be minimized by setting up low operating tension in R2R process. In low tension, slippage between a moving substrate and a roller would be generated when the operating speed is increased. And scratch would be occurred when slippage is generated due to an air entrainment, which is related to the thickness of the air film. The thickness of the air film is increased when operating speed is increased as shown by simulation based on mathematical model. The occurrence of scratch in conductive pattern printed by roll to roll process is a critical damage because it causes degradation or failure of electrical property of it.

• The Korea Journal of Herbology
• /
• v.29 no.6
• /
• pp.103-109
• /
• 2014

Objectives : The purpose of this study aimed to investigate that dieckol - isolated from Ecklonia cava - supplementation can improve cognitive ability in mice. Methods : 48-male mice(6 weeks old) were divided into four groups; High-Dieckol group(n=12), Low-Dieckol group(n=12), Placebo group(n=12), Control group(n=12) and they were administered orally 5 days per week for 4 weeks at the same time. We performed Morris water maze test, Passive avoidance test, Blood serotonin analysis. And there was examined on neurogenesis in dentate gyrus of hippocampus using 5-bromo-2'-deoxyuridine (BrdU) to label proliferating cells. Results : The results are as follows; As a Morris water maze results, Trial duration was significantly decreased in high dieckol group comparing to placebo group and control group. Distance to target was significantly decreased in high dieckol group and low dieckol group comparing to placebo group and control group. Mean speed was significantly low in high dieckol group comparing to low dieckol group, placebo group and control group. As a Passive avoidance test results, latency time was significantly long in high dieckol group comparing to low dieckol group, placebo group and control group. BrdU cell count was significantly high in high dieckol group comparing to low dieckol group, placebo group and control group. Conclusions : As a conclusion, it is considered that dieckol supplementation might improve learning and cognitive ability.

• Reproductive and Developmental Biology
• /
• v.36 no.3
• /
• pp.141-145
• /
• 2012

The present study was conducted to develop a simple method for porcine oocyte maturation without $CO_2$ regulation. In experiment 1, we evaluated that the effect of $CO_2$ non-supplement on porcine oocyte maturation. Cumulusoocyte complexes (COCs) were collected from 2~6 mm follicles and divided into three groups (Control, tube-$CO_2$, and tube-non-$CO_2$). For control, COCs were cultured in 4-well multidish in a $CO_2$ incubator. For tube-$CO_2$, COCs were cultured in a round-bottom tube in a $CO_2$ incubator, and for tube-non-$CO_2$, COCs were cultured in a round-bottom tube sealed tightly without $CO_2$ supplement in a dry incubator. The proportion of oocytes reached to metaphase II (M-II) was not significantly different among three groups (87.9% to 91.4%). In experiment 2, we evaluated the effect of $CO_2$ non-supplement during oocyte maturation on development of embryos. Oocytes with a polar body were divided into two groups (Control and tube-non-$CO_2$) and applied 1.1 kV/cm or 1.2 kV/cm voltages for parthenogenetic activation. After activation, embryos were cultured for 6 days and examined the development. The proportion of embryos cleaved was not significantly different among treatment (86.3% to 91.5%). The proportion of embryo reached to blastocyst stage was not significantly different among treatment (13.9% to 25.2%). The cell number of blastocysts was not significantly different among treatment (29.0 to 32.4). In conclusion, oocytes cultured in a dry incubator without $CO_2$ supplement have enough competence to development after parthenogenetic activation. These results would be useful for transporting oocytes or embryos a long distance.

• The Transactions of the Korea Information Processing Society
• /
• v.6 no.1
• /
• pp.148-158
• /
• 1999

ABR traffic form ATM LAN is controlled through RM cell, and the interface function to public ATM network is necessary to provide ABR service efficiently. This paper presnets new interface architecture, which is based on "Projected Node" [6]. using AIPU(ABR Interface Proxy Unit) to support ABR traffic streams incoming from ATM LAN in the public ATM network. For the efficient interworking, the AIPU has designed for interworking functions with ERICA switch mechanism. Conventional ERICA switch mechanism specified in TM 4.0 is basically used for short distance comparative to public network, however AIPU adopts the novel control mechanism to cover logng roud trip time (RTT). To improve the problems and to provide a dynamic range of UCI(Update Count Interval), this paper proposes, a novel control scheme, DUCI ( Dynamic Update Count Interval. And the paper shows inefficiencies of ERICA mechanism with fixed UCI through the simulation results, and represents the performance enhancement of DUCI mechanism developed to adjust the update count interval dynamically.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.61 no.9
• /
• pp.1350-1357
• /
• 2012

Medical system for personal health management recently changes its paradigm from hospital service to self home care based on ubiquitous technology for healthcare anywhere at any time. The present study developed a wireless bio-signal measurement system for patients to self manage pulmonary disease and benign prostate hyperplasia(BPH), both of which are chronic diseases with increasing frequency in modern society. Velocity-type respiratory air flow transducer adapted to develop respiratory module for pulmonary disease management was simplified in structure to measure uni-directional flow since most important diagnostic parameters are evaluated on the expiratory flow signal only. Standard weight measurement technique was introduced to obtain urinary flow signal for BPH management. Three load cell signals were acquired for averaging to minimize noise, followed by accuracy evaluation. Transmission and receiver modules were also developed with user program for wireless communication. Averaged relative errors were 2.05 and 1.02% for respiratory volume and maximal flow rate, respectively, and the relative error was 2.17% for urinary volume, demonstrating that both modules enabled very accurate measurements. Wireless communication distance was verified within 15m, long enough for home care application. The present system allows the user to select a necessary measurement module on a particular health demand and to immediately provide the self-test results, thus better quality health care would be possible.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.66 no.12
• /
• pp.1889-1894
• /
• 2017

Global automobile manufacturers are developing electric vehicles (EVs) to eliminate the pollutant emissions from internal combustion vehicles and to minimize fossil fuel consumptions for the future generations. However, EVs have a disadvantage of shorter traveling distance than that of conventional vehicles. To answer this shortfall, more batteries are installed in the EV to satisfy the consumer expectation for the driving range. However, as the energy capacity of the battery mounted in the EV increases, the amount of heat generated by each cell also increases. Naturally, a better battery thermal management system (BTMS) is required to control the temperature of the cells efficiently because the appropriate thermal environment of the cells greatly affects the power output from the battery pack. Typically, the BTMS is divided into an active and a passive system depending on the energy usage of the thermal management system. Heat exchange materials usually include gas and liquid, semiconductor devices and phase change material (PCM). In this study, an application of PCM for a BTMS was investigated to maintain an optimal battery operating temperature range by utilizing characteristics of a PCM, which can accumulate large amounts of latent heat. The system was modeled using Dymola from Dassault Systems, a multi-physics simulation tool. In order to compare the relative performance, the BTMS with the PCM and without the PCM were modeled and the same battery charge/discharge scenarios were simulated. Number of analysis were conducted to compare the battery cooling performance between the model with the aluminum case and PCM and the model with the aluminum case only.

• Tunnel and Underground Space
• /
• v.19 no.6
• /
• pp.473-478
• /
• 2009

The accuracy of point load apparatus is depend on point to point coaxial fitting. Also, the estimation of applied point load using the pressure gauge frequently lead to erroneous results. An improved point load apparatus has been developed in this study by mounting linear bearing on polished support rod, and eccentric error of point to point axis has been sustained less than 0.1 mm even under series of extreme work load conditions. Two digital displacement gauges are attached to measure the distance from point to point with sample specimen. A load cell mounted at the end of upper conical platen measure the applied net load on sample instead of preassure gauge. Total of 107 point load tests has been achieved to assure the quality and performance of developed apparatus. This exercise turned out to be successful.