• 제목/요약/키워드: Disintegration

검색결과 384건 처리시간 0.03초

용융 분무에 의한 질산암모늄 액적의 분열 메카니즘 (Disintegration Mechanism of Ammonium Nitrate Droplets by Melt Spray)

  • 안진환;김재경;김준형;구기갑
    • 한국군사과학기술학회지
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    • 제12권2호
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    • pp.206-212
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    • 2009
  • The pressurized spray system with nitrogen gas was designed to fabricate the spherical AN(ammonium nitrate) particles. When AN melt was sprayed from a nozzle with equivalent diameter of 0.28mm into an ambient dry air, the ligament breakup mechanism of the molten AN was found to be responsible for the droplet formation(or disintegration) of AN melt. In the experimental range of spray temperature with $170{\sim}200^{\circ}C$ and atomization pressure with $0.1{\sim}0.4MPa$, the spherical AN particles with mean diameter of $130{\sim}250{\mu}m$ were obtained.

충돌제트로 생성되는 분무의 특성에 관한 연구 (A Study on the Characteristics of the Spray Produced by Two Impinging Jets)

  • 강보선
    • 한국분무공학회지
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    • 제2권4호
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    • pp.22-28
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    • 1997
  • In this paper an experimental study of a spray created by two impinging jets is presented utilizing a novel two-reference-beam double-pulse holographic technique. Visualization of the overall spray pattern as well as measurements on the size and velocity of the droplets were performed with the special emphasis on the effect of physical properties of liquids. The overall spray pattern clearly revealed the inherent wave nature In the disintegration process of this type of atomization. The structure of liquid elements near the impingement point is indicative of the mechanisms of the disintegration process. Surface tension plays an important role in the droplet size without any noticeable effect on the spray pattern, whereas viscosity affects the structure without any significant effect on the droplet sire. The droplet velocities were not affected by liquid properties.

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Investigation of Turbulent Spray Disintegration Characteristics Depending on the Nozzle Configuration

  • Lee, Sam-Goo;Song, Kyu-Keun;Park, Byung-Joon
    • Journal of Mechanical Science and Technology
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    • 제16권4호
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    • pp.572-579
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    • 2002
  • The experimental measurements were carried out to examine turbulent disintegration characteristics ejecting from a counter-flowing internal mixing pneumatic nozzle under variable conditions of swirl angles and air pressures. The air injection pressure was varied from 60 kPa to 180 kPa and four counter-flowing internal mixing nozzles with axi-symmetric tangential-drilled holes at swirl angle of 15$^{\circ}$, 30$^{\circ}$, 45$^{\circ}$, and 60$^{\circ}$to the central axis have been specially designed. The experimental results were quantitatively analyzed, focusing mainly on the comparison of turbulent atomization characteristics issuing from an internal mixing swirl nozzle. To illustrate the swirl phenomena, the distributions of mean velocities, turbulence intensities, volume flux, and SMD (Sauter Mean Diameter, or D$\sub$32/) were comparatively analyzed.

베르베린 제제의 생체 이용율에 관한 연구 (Studies on the Bioavailability of Berberine Preparations)

  • 양재헌;김영일
    • Journal of Pharmaceutical Investigation
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    • 제22권1호
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    • pp.55-62
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    • 1992
  • In order to measure the bioavailability of Coptidis Rhizoma preparations, berberine was extracted by the mixture (1:1 v/v) of methanol and water from Coptidis Rhizoma and formulated into pills with some excipients. Disintegration time, dissolution rate, intestinal absorption rate, antibacterial effect, and serum concentration were measured. All pills were disintegrated about 60 minutes in gastric and intestinal juices and disintegration time did not change upon storage at $40^{\circ}C$ for 30 days. The pills manufactured using the extract which was extracted with the solvent containing dilute sulfuric acid showed faster dissolution and absorption from the small intestine than the other samples. It also showed not only the largest area under the serum concentration time curve and relative bioavailability, but also more potent antibacterial effect against gram-positive and gram-negative bacterias than the other samples. The correlation of the dissolution rate with absorption rate constant or $t_{max}$ showed a significant linear relationship.

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시판 설프이속사졸정의 용출거동 및 상대 생체이용율 (Dissolution Behavior and Relative Bioavailability of Commercially Available Sulfisoxazole Tablets in Humans)

  • 고익배;이용복
    • Journal of Pharmaceutical Investigation
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    • 제17권3호
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    • pp.127-133
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    • 1987
  • Dissolution characteristics and urinary excreted amount of commercially available three brands of sulfisoxazole tablets were investigated in order to elucidate the in vitro-in vivo correlations and relative bioavailability in humans. All the tablets tested met the K.P. IV and the USP XXI specifications for tablet weight variation, content uniformity, disintegration and dissolution. The disintegration and dissolution rate constants of sulfisoxazole tablets in pH 2.0 HCl-KCl buffer were reduced more significantly (p<0.05) than those in diluted HCl $(1{\rightarrow}12.5)$ and pH 6.5 phosphate buffer. It seemed to be attributed to the pH dependent solubility of sulfisoxazole. We could see that the relative bioavailability of brand B to sulfisoxazole powder was about 90% and that its value was higher than those of other two brands from the urinary excretion data obtained from eight healthy male volunteers by means of Latin square cross over design. No useful correlation was observed between the in vitro and in vivo studies in this experiment.

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타원형 노즐의 내부유동 구조가 액주분열에 미치는 영향 (Effect of Flow Structure Inside Nozzle on the Liquid Jet Breakup of Elliptical Nozzle)

  • 구건우;홍정구
    • 한국분무공학회지
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    • 제18권1호
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    • pp.44-54
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    • 2013
  • An experimental study was performed to investigate the liquid jet breakup of a circular nozzle and elliptical nozzles. Furthermore Numerical simulation was attempted to investigate the internal flow structure in the circular and elliptical nozzles. This study showed that the disintegration characteristics of the liquid jet of elliptical nozzles were much different from those of the circular nozzle. The liquid jet issued from the elliptical nozzles became more unstable at the same injection pressure. Surface breakup was observed at the jet issued from the elliptical nozzles with the increase of injection pressure. The disintegration of the liquid jet of elliptical nozzles was related with the internal flow structure which is revealed from the numerical simulation.

정제의 제조설계에 관한 연구 : 직타법에 의한 Prednisolone 정제의 제조에 있어서 무수유당 및 옥수수전분의 영향 (Studies on the Tablet Product Design : Effects of Anhydrous Lactose and Corn Starch on the Preparation of Prednisolone Tablet by Direct Compression Method)

  • 권종원;민신홍;이상의;김용배
    • 약학회지
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    • 제20권1호
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    • pp.63-69
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    • 1976
  • Prednisolone tablet product design problem was structured as constrained optimization problem and subsequently solved by multiple regression analysis and Lagrangian method of optimixation. Prednisolone was the drug chosen and anhydrous lactose and corn starch were the adjuvants. The effect of anhydrous lactose and corn starch concentrations on tablet hardness, volume, disintegration time and in vitro release rate was studied. The concentrations of anhydrous lactose and corn starch used in this experiment were 30-60 percent and 5-30 percent, respectively. A full second-order (quadratic) model with all possible two-factor interactions was employed. To obtain the values of anhydrous lactose and corn starch which miniumize the in vitro : release time (t$_{60%}$) subject to the constraint on tablet hardness, disintegration time and volume, we solved the Lagrange function. Multiple correlation coefficients for the regression models were correlated at less than 0.05 level and it was found that the optimum concentrations of anhydrous lactose and corn starch were 45 percent and 21 percent, respectively.

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인간 포미바이러스 인테그라제의 생화학적 특성 (Biochemical Characterization of Human Foamy Virus Integrase)

  • 강승이;오수아;이학성;한성태;서진욱;신차균
    • 약학회지
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    • 제48권1호
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    • pp.13-19
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    • 2004
  • A bacterial expression vector for the human foamy virus (HFV) integrase was constructed and expressed in Escherichia coli. By two-step purification using a nickel-chelated column and a SP-sepharose chromatography; the HFV into-grase protein of 43 kDa was purified to near homogeneity, and used to investigate biochemical characteristics of the enzymatic activities, such as endonucleolytic and disintegration activities. Oligonucleotide substrates were specifically and efficiently cleaved by the purifed HFV integrase in the presence of Mn $^{+2}$, but not in the presence of Mg $^{+2}$, indicating that the HFV integrase is not able to use Mg $^{+2}$ as a cofactor Endonucleolytic reaction was almost completed in 60 min at 37 $^{\circ}C$. In addition, the maximum enzymatic activities were observed at 5 mM Mn $^{+2}$ in the buffer of which pH was from 7.0 to 9.0. The endonucleolytic activities were dose-dependently blocked in the addition of baicalein or chicolic acid which is a well-known inhibitor of human immunodeficiency virus integrase.

과립의 크기가 인삼정제의 물리적 특성에 미치는 영향 (Effect of Granule Size on Physical Characteristics of Ginseng Tablet)

  • 박명한;성현순;김우정
    • Journal of Ginseng Research
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    • 제4권1호
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    • pp.96-103
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    • 1980
  • The effect of granule size of dried red ginseng extract on physical characteristics on tablet such as hardness, color, yield and disintegration time was studied. A moisture proofing agent was found to be necessary to form granules without serious absorption of moisture. The result showed that decrease in particle size resulted increase of values in weight, hardness and disintegration time. The granule size of 60∼80 mesh was found to be optimum for proper color uniformity and other physical characteristics of tables.

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소염효소제(消炎酵素劑)의 약제학적(藥劑學的) 연구(硏究) (Pharmaceutical Studies on Anti-inflammatory Enzyme Preparations)

  • 이강춘;양중익;민신홍;이상의;김용배
    • Journal of Pharmaceutical Investigation
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    • 제8권1호
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    • pp.27-36
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    • 1978
  • Spherical granules of anti-inflammatory enzyme were prepared by mixer granulation and the recovery rate of enzyme activity by processing was compared with tablet ones. In the enteric granule coating .processing, the effect of the amount of coating solution and the conentration of fatty alcohol on disintegration and stabilities on the accelerated conditions were also studied. Being prepared in non-pressure and non-aqueous condition, spherical granules of enzyme made better recovery of enzme activity than tablet ones by 10 times. Combined processing of both mixer granulation and enteric granule film coating provided the noble enteric coated granules, in the sense of disintegration and stabilities, was obtained from using 0.125% fatty alcohol in coating solution.

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