• Archives of Pharmacal Research
• /
• v.18 no.1
• /
• pp.51-55
• /
• 1995

A facile convenient syntheses of the titled compounds, via reacting the precusor 2-amino-2-(pentane-2, 4-dion-3-yithio)-6-phenylpyrimidine-5-carbonitrile (1) with nitrogen nucleophiles and with the carbanions of some active methylene compounds, is reported. Chemical and spectroscopic evidence of the newly syntheised compounds are described.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.30 no.9A
• /
• pp.830-837
• /
• 2005

ISI is caused by delay spread in the multipath channel environment. There are two kinds of channel equalizer: Linear and Non-Linear type according to the structures. In this paper, we propose an improved adaptive linear equalizer to mitigate ISI. The proposed adaptive equalizer is constructed by using asymmetrical Dsmvenu filter based on USE sub-optimal receiver. Asymmetrical structure of the transversal filter is realized by moving the main tap position from center to side. If this structure is used, we can divide ISI to precusor and postcusor. As a result the proposed equalizer has a larger extended compensation range than conventional adaptive linear equalizer. In computer simulation, we compare the bit error rate performance of the proposed linear equalizer with the conventional one on the S-V channel which is modeled for WB systems.

• 한국생물공학회:학술대회논문집
• /
• 2001.11a
• /
• pp.483-486
• /
• 2001

Growth and tropane alkaloids(hyoscyamine and scopolamine) contents were studied in root cultures from Scopolia paruiflora. All excised roots grew well, even without an addition of a growth regulators. Scopolia roots could be divided scopolamine-rich species. Among the culture media, SH medium was the best for tropane alkaloids production from the hairy roots, whereas the growth increased in SH medium. In precusor experiments, feeding of hyoscyamine was promotive for scopolamine formation. Abiotic elicitors made a slightly production promotion effect.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2003.11a
• /
• pp.111-111
• /
• 2003

The peroxo titanic acid solution was successfully prepared using titanium trichloride as a precursor. The basic properties of the TiO2 film prepared by the solution were investigated in view of phase change, bandgap energy, crystalline size etc. The film displayed amorphous TiO$_2$ at room temperature, anatase above 281$^{\circ}C$ and a mixture of anatase and rutile at 99$0^{\circ}C$, The crystalline size increases with annealing temperatures, while the bandgap energies decrease due to the quantum size effect and the formation of rutile phase which has low bandgap energy. As a result of TG-DTA, it was found that annealing treatment at 99$0^{\circ}C$ for 2h formed a mixtures of anatase and rutile through three steps: (1) the removal of physically adsorbed water (2) the decomposition of peroxo group (3) amorphous-anatase or anatase-rutile phase transformation.

• Childhood Kidney Diseases
• /
• v.13 no.2
• /
• pp.278-281
• /
• 2009

Bilateral renal enlargement is a very rare manifestation as the primary presenting feature of acute lymphoblastic leukemia. We are reporting an unusual clinical picture of a 9-month-old male patient diagnosed as precusor B-cell lymphoblastic leukemia, who showed bilateral nephromegaly without any hepatosplenomegaly at the time of initial presentation.

• Journal of Powder Materials
• /
• v.10 no.1
• /
• pp.1-5
• /
• 2003

Nano-sized WC powders were synthesized by vapor phase reaction using the precusor of tungsten ethoxide under helium and hydrogen atmosphere. The phases of the powder were varied with reaction Bone and gas flow rate. The powder size was about 30nm in diameter, and the tungsten carbide powder was coated by carbon layer. The synthesis of nano-sized WC powders was promoted as the hydrogen gas flow rate became higher. Inversely, tungsten oxide was formed by increasing the flow rate of helium gas. The synthesized powders were analyzed by XRD, FE-SEM, carbon analyzer etc.

• Proceedings of the KIEE Conference
• /
• 2006.07d
• /
• pp.2211-2212
• /
• 2006

Ferroelectric PZT (70/30) thick films were fabricated by the screen printing method. And the PZT (30/70) precusor solution were infiltrated by the spin-coating method on the PZT thick films to obtain a densification. All PZT thick films were sintered at $1050^{\circ}C$ for 10 min. Structural properties, such as crystalline structure, microstructures and compositional ratio, of PZT thick films were investigated with the variation of the number of sol coatings using XRD, SEM and EDS, respectively. All PZT thick films exhibited a perovskite polycrystalline structure without a pyrochloer phase. The thickness of PZT thick films, 4-times screen-printed, was approximately $60{\mu}m$. And the densification of the PZT thick films increased with increasing the number of sol coatings.

• Proceedings of the KIEE Conference
• /
• 2006.07a
• /
• pp.579-580
• /
• 2006

Ferroelectric PZT (70/30) thick films were fabricated by the screen printing method. And the PZT (30/70) Precusor solution were infiltrated by the spin-coating method on the PZT thick films to obtain a densification. All PZT thick films were sintered at $1050^{\circ}C$ for 10min. Structural properties, such as crystalline structure, microstructures and compositional ratio, of PZT thick films were investigated with the variation of the number of sol coatings using XRD, SEM and EDS, respectively. All PZT thick films exhibited a perovskite polycrystalline structure without a pyrochloer phase. The thickness of PZT thick films, 4-times screen-printed, was approximately 60fm. And the densification of the PZT thick films increased with increasing the number of sol coatings.

• Journal of the Korean Ceramic Society
• /
• v.30 no.7
• /
• pp.563-570
• /
• 1993

Spherical, monosized gadolinium compound was prepared by the reaction of Gd(NO3)3 solution with decomposition products of urea in the solution at evaluated temperature. Chemical composition and calcination characteristics of spherical gadolinium compound prepared were investigated by X-ray IR and TG-DTA. The approximate chemical composition of the spherical particle precipitated was Gd(OH)CO3.1.5H2O. Gd(OH)CO3.1.5H2O was calcined to monoclinic type Gd2O3 at 115$0^{\circ}C$ via cubic type Gd2O3 near $600^{\circ}C$. The effects of various parameters such as pH, temperature, concentration ratio of urea to gadolinium precusor, ageing time, and others material (CCl3COOH and HOCNH2) in stead of urea as precipitating agent on the properties of the resulting precipitates were studied systematically.

• Applied Microscopy
• /
• v.24 no.4
• /
• pp.52-60
• /
• 1994

The developing ovarian oocyte of Dendrolimus spectabilis has been studied by using electron microscopical techniques. After yolk formation the vitelline membrane was laid down in the intercellular space between the follicle cell and the oocyte. But before the vitelline membrane formation the granules with high electron density that the vitelline membrane precusor are observed in the follicle cell. At the late vitellogenesis stage these granules were transported into the intercellular space between the follicle cells and the oocyte. These granules fuse to each other and larger bodies which eventually produce the vitelline membrane. The vitelline membrane was distinguished into the light inner and dark outer membrane. Next the chorion was laid down. It was apparent that the chorion was laid down in the intercellular space immediately adjacent to the vitelline membrane, and that it was formed by the follicle cells only.