• Title/Summary/Keyword: Dissolution condition

Search Result 230, Processing Time 0.025 seconds

Metal Ion Dissolution in Nitric Acid with Lead-Borosilicate Glass for Barrier Ribs in PDP

  • Kim, Jae-Myung;Lee, Chong-Mu;Kim, Hyung-Sun
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2005.07b
    • /
    • pp.1252-1254
    • /
    • 2005
  • Recently, PDP barrier ribs require the formation of complex structure so that they are usually formed by etching method. For producing the fine ribs structure, during the etching process the metal ions of matrix (glass) of barrier materials should be understood on the etching mechanism with etching condition. We analyzed the quantity of Pb, Si, and B ions from the etch solution as a function of etching time.

  • PDF

Alleviating and Promoting Factors on Dissolution Intention in Low Commitment Buyer-Seller Relationships (저결속 구매자-판매자 관계에서 관계해지의 완화요인과 촉진요인)

  • 오세조;강보현;김상덕
    • Journal of Distribution Research
    • /
    • v.9 no.3
    • /
    • pp.21-47
    • /
    • 2004
  • This study has investigated the effects of relieving and promoting factors on dissolution intention under the condition of low commitment buyer-seller relationships. Based on intensive literature reviews, eight alleviating factors (dependence, cooperation, communication, relational norms, transaction specific investments, relationship termination costs, satisfaction, and trust) and five promoting factors (opportunism, conflict, goal incongruity, attractiveness of alternatives, and unfairness) were included. A total of thirteen hypotheses were testee using data collected from a dining franchising system. Among 300 collected, 79 cases of low commitment buyer-seller relationships were analyzed. The results showed that eight out of thirteen hypotheses were supported. But five hypotheses related to the variables of cooperation, transaction specific investments, relationship termination costs, attractiveness of alternatives, and opportunism were not supported. following a detailed presentation of the analysis results, the paper concludes by discussing the academic and managerial implications of the findings.

  • PDF

Effects of Pulping Conditions in the Reconstituted Tobacco Sheet Making Process on the Properties of the Pulp Slurry (판상엽 펄퍼 운전 조건에 따른 펄핑특성 변화)

  • Sung, Yong-Joo;Han, Young-Lim;Kim, Kun-Soo;Rhee, Moon-Soo;Ha, In-Ho;Lee, Ki-Yeul;Lee, Young-Eh;Kim, You-Choul
    • Journal of the Korean Society of Tobacco Science
    • /
    • v.28 no.2
    • /
    • pp.117-123
    • /
    • 2006
  • The pulping process in a papermaking process for a reconstituted tobacco sheet (RECON) was evaluated. For the practical information, the experiments were conducted in a real mill. Two pulping conditions were chosen and changed depending on the feasibility, such as the pulping temperature and the properties of pulping water. The higher pulping temperature resulted in the easier dissolution of solubles from the raw materials. However, the efficiency of screw press process was decreased by the higher pulping temperature, which resulted in the reduction of the HWS and the concentration in the #1 screw press filtrate. The addition of SEL(Strong extracted liquor) to pulper affected the efficiency of dissolution and the final concentration of #1 screw press filtrate. Although the higher SEL resulted in the less dissolution of the solubles from the raw materials, the concentration of the #1 screw press filtrate was greatly increased by the higher addition of SEL, which could provide much better efficiency to the following evaporation process of the filtrate and could increase the whole productivity.

Stability Improvement of Esomeprazole Magnesium Dihydrate Enteric-Coated Tablet by Adding Alkalizing Agents (에스오메프라졸 마그네슘 이수화물을 함유하는 장용성 제제의 안정성 개선)

  • Cho, Young Ho;Jeon, Hyo Bin;Lee, Jong-Hwa;Lee, Gye Won
    • KSBB Journal
    • /
    • v.32 no.2
    • /
    • pp.108-116
    • /
    • 2017
  • Omeprazole, a benzimidazole derivative, suppresses gastric acid secretion by inhibiting $H^+/K^+$ ATPase in gastric parietals cells, and by reducing $H^+$ concentration. To improve stability of esomeprazole magnesium dihydrate (ESMD), enteric-coated preperation was composed of core tablet, subcoating and enteric coating layer. We were evaluated in vitro dissolution characteristics between test and reference ESMD preparation and stability. We could prepare enteric-coated formulation of ESMD by controlling disintegrating agent and coating ratio which could rapidly dissolved in neutral or alkali medium. The formulation D5 with crospovidone of 1.25% and coating ratio of 16.25% had a similar dissolution behavior compare to reference preparation. Difference factor ($f_1$) and similarity factor ($f_2$) were 0~15 and 50~100 and there was no significant difference in bioequivalence between formulations. The content and dissolution rate of formulation D5 were $96.54{\pm}0.21$ and $78.56{\pm}0.87%$ without change of color in accelerated condition ($40^{\circ}C$, RH 75%, high density polyethylene (HDPE) container) for 6 months. This study concluded that our enteric coated preparation of ESMD could be an useful method to improve stability of unstable drug without direct contact with coating material.

Characteristics of Three-Component Carbonate Electrolytes in Terms of Oxygen Reduction and NiO Dissolution (산소환원 및 산화니켈의 용해거동으로부터 본 삼원계 탄산염 전해질의 특성)

  • Lee, C.G.;Taniguchi, T.;Uchida, I.
    • Journal of the Korean Electrochemical Society
    • /
    • v.6 no.3
    • /
    • pp.178-182
    • /
    • 2003
  • The oxygen reduction and NiO dissolution behaviors in Li-Na-K three component carbonate melts have been investigated with various compositions through electrochemical and chemical ways. The oxygen reduction currents and NiO solubilities were measured at $650^{\circ}C$ and atmospheric condition in Li-Na-K =47.4-32.6-20, 60-20-20, 50-40-10, $40-40-20 mol\%$ carbonate melts. The oxygen reduction currents showed dependence on the composition, indicating oxygen solubility is a function of carbonate composition. At the composition of $ Li-Na-K=50-40-10 mol%$, a broader peak was observed, suggesting different oxygen reduction mechanism probably prevails in this composition. In contrast, insignificant differences of NiO solubility were obtained among the compositions.

Aluminum Brazing and Its Principle (알루미늄의 브레이징과 원리)

  • Lee, Soon-Jae;Jung, Do-Hyun;Jung, Jae-Pil
    • Journal of the Microelectronics and Packaging Society
    • /
    • v.24 no.4
    • /
    • pp.1-7
    • /
    • 2017
  • Aluminum alloys have been widely used in many fields such as electronic, structure, aero-space and vehicle industries due to their outstanding thermal and electrical conductivity as well as low cost. However, they have some difficulties for using in brazing process because of the strong oxide layer of $Al_2O_3$ on the surface of Al alloy. In addition, their melting point is similar to that of brazing filler metal resulting in thermal damage of Al alloys. Therefore, it is very important to understand the brazing principles, filler metal and its properties such as wetting, capillary flow and dissolution of base metal in the Al brazing process. This paper reviews the brazing principles, aluminum alloys, and brazing fillers. In the case of brazing principle, some formula was used for calculation of capillary force and the dissolution to obtain the best condition of Al brazing. In addition, the advanced research trends in Al brazing were introduced including thermal treatment, additive for improving property and decreasing melting point in Al brazing process.

DISSOLUTION AND BURNUP DETERMINATION OF IRRADIATED U-Zr ALLOY NUCLEAR FUEL BY CHEMICAL METHODS

  • Kim, Jung-Suk;Jeon, Young-Shin;Park, Soon-Dal;Song, Byung-Chul;Han, Sun-Ho;Kim, Jong-Goo
    • Nuclear Engineering and Technology
    • /
    • v.38 no.3
    • /
    • pp.301-310
    • /
    • 2006
  • Destructive methods were used for the burnup determination of U-Zr alloy nuclear fuel irradiated in the High-flux Advanced Neutron Application Reactor (HANARO) at KAERI. The dissolution rate of unirradiated U-Zr alloy fuel in $HNO_3$/HF mixtures was investigated for the experimental conditions of a different temperature, and initial concentrations of HF and $HNO_3$. The irradiated U-Zr alloy fuel specimen was dissolved in a mixed acid condition of 3 M HNO3 and 1 M HF at $90^{\circ}C$ for 8 hours under reflux. The total burnup was determined from measurement of the Nd isotope burnup monitors. The method includes U, Pu, $^{148}Nd,\;^P{145}Nd+^{146}Nd,\;^{144}Nd+^{143}Nd$ and total Nd isotopes determination by the isotope dilution mass spectrometric method (IDMS) using triple spikes $(^{233}U,\;^{242}Pu\;and\;^{150}Nd)$. The effective fission yield was calculated from the weighted fission yields averaged over the irradiation period. The results are compared with that obtained by the destructive -spectrometric measurement of the $^{137}Cs$ monitor.

EFFECT OF MICROSTRUCTURE ON MECHANICAL PROPERTIES IN FRICTION STIR WELDED CAST A356 ALUMINUM ALLOY

  • Sato, Yutaka S.;Kaneko, Takayasu;Urata, Mitsunori;Kokawa, Hiroyuki
    • Proceedings of the KWS Conference
    • /
    • 2002.10a
    • /
    • pp.493-498
    • /
    • 2002
  • Friction stir welding (FSW) is a relatively new solid-state joining process which can homogenize the heterogeneous microstructure by intensely plastic deformation arising from the rotation of the welding tool. The present study applied the FSW to an A356 aluminum (AI) alloy with the as-cast heterogeneous microstructure in the T6 temper condition, and examined an effect of microstructure on mechanical properties in the weld. The base material consisted of Al matrix with a high density of strengthening precipitates, large eutectic silicon and a lot of porosities. The FSW led to fragment of the eutectic silicon, extinction of the porosities and dissolution of the strengthening precipitates in the Al alloy. The dissolution of strengthening precipitates reduced the hardness of the weld around the weld center and the transverse ultimate tensile strength of the weld. Longitudinal tensile specimen containing only the stir zone showed the roughly same strength as the base material and a much larger elongation. Moreover, Charpy impact tests indicated that the stir zone had remarkably the higher absorbed energy than the base material. The higher mechanical properties of the stir zone were attributed to a homogenization of the as-cast heterogeneous microstructure by FSW.

  • PDF

Effect of Polyethylene Glycol on Physicochemical Property in Dispersing Film Formulation (분산형 필름제형의 물리적 특징에 미치는 폴리에틸렌글리콜의 영향)

  • Cho, Young Ho;Lee, Jong-Hwa;Lee, Gye Won
    • KSBB Journal
    • /
    • v.31 no.4
    • /
    • pp.291-299
    • /
    • 2016
  • In this study, Indomethacin, the poorly water soluble drug, was selected and prepared dispersing oral disintegrating films according to the molecular weight of polyethylene glycol (PEG) which are sort of dispersing agents. Also the molecular weight and content of PEG were evaluated effect on the degree of dispersion, physical property and dissolution when making oral dispersing film containing indomethacin to find appropriate condition and suggested guidelines of making oral dispersing film. The appropriate dispersing ratio of the amount of surfactants and dispersing agent were 1% and 4%, also the stability dropped in the PEG molecular weight of 4000 or more. Drying time of oral dispersing film was $90^{\circ}C$ for 10 minutes to 12 minutes that dispersing film's property about flexibility, detachability were very good. The oral dispersion film's content used PEG 400 was $98.6{\pm}0.5%$ and the most uniform. As the molecular weight of PEG increased, dissolution time also increased. On the basis of evaluation parameter, PEG with 400~600 of molecular weight was selected as good dispersing agent in oral dispersing film. Therefore, it can be suggested guideline of preparation application study in oral dispersing film.

The Effect of Electrolysis Condition on the Zinc-Aluminum Composite Electro Plating (Zn-Al系 復合電氣鍍金에 미치는 電解條件의 影響)

  • Ye, Gil-Jae;Gang, Sik-Seong;An, Deok-Su
    • Journal of the Korean institute of surface engineering
    • /
    • v.20 no.3
    • /
    • pp.118-126
    • /
    • 1987
  • The Zn-Al composite electroplating was studied by using chloride zinc bath containing metal hydroxides $(Zn(OH)_2,\;Al(OH)_3))$ and aluminium powder. The size of Al powder codeposited in the beaker bath with Al powder of-400 mesh was under 10${\mu}m$. The Zn-Al composite was electro-deposited at 40$^{\circ}C$ in the ranges of current density of 5-50 A/$dm^2$ in the flowing electrolyte. The content of aluminium particles codeposited increased slightly with increasing flow rate of electrolyte from 0.5 m/sec to 1.0 m/sec, and decreased with increasing current density from 5 A/$dm^2$ to 50 A/$dm^2$. The content of aluminium particles codeposited by using the electrolyte containing zinc hydroxide(0.1M) was 2~4 wt%. The Al powder was codeposited mainly near the surface layer of the electrodeposits. The dissolution rate of aluminium particles in the electrolyte containing 0.1M $Zn(OH)_2$ and Boric acid was 0.41 g/l. day in comparison with 1.5 g/l. day dissolution rate in pure chloride bath.

  • PDF