• 대한의생명과학회지
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• 제13권4호
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• pp.361-368
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• 2007

Biological samples can be fixed either by chemical method by using chemical solution or physical methods by using heat treatment. The problem in traditional heat fixation is unsatisfactory quality due to uneven heat conduction in specimen and loss of inner cell contents. Chemical fixation method also bears several intrinsic problems like the limit in specimen size, time consumption in fixative impregnation, and loss of low molecular weight cell components. These factors deteriorate the quality of fixed specimen, thus limit the magnification and contrast of tissue pictures. Microwave heat has been reported to be a good alternative to current chemical methods to overcome these problem. In this study, we tried to introduce the microwave energy method to routine fixation work in hospital. We replaced chemical fixative with saline to provide moderate reaction condition, and used frozen section to reduce time for sample preparation. Temperature was measured at each experiment. The fixation of rat kidney tissue with 2.45 GHz electromagnetic wave and saline showed similar result to the control group fixed with traditional chemical method. Human tumor tissue fixed with 2.45 GHz electromagnetic in frozen section was improved in terms of histochemistry of PAS and immunohistochemistry of tumor marker like cytokeratin. Total turnaround time was reduced from $24\sim38$ h to to $2\sim4$ h. In conclusion, the quality of samples prepared by microwave heating method was at least as good as that of traditional method. If the condition for the fixation of different specimens is standardized, this new method could be applied to routine work in hospital, and could save working time as well.

• 한국세라믹학회지
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• 제49권5호
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• pp.454-460
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• 2012

The nano-sized zirconia powders were synthesized in an impregnation method using pulp and $ZrOCl_2{\cdot}8H_2O$ as an initial material. The synthesized powders were characterized by XRD and FE-SEM. The particle size of the powder was controlled by preparation conditions, such as drying temperature and time. As a result of the various drying and calcination conditions, 30~50 nm sized homogeneous zirconia particles were obtained at $800^{\circ}C$ for 1 h. Crystallization and the rapid growth of particles were accelerated with increasing calcination temperature and time. Tetragonal phase generated below $800^{\circ}C$ were transferred to monoclinic phase with increasing calcination temperature and time. Moreover, above $800^{\circ}C$, heat treatment time had very large influence on the particle growth, and the change of drying condition also had large influence on the growth of a crystal.

• 한국세라믹학회지
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• 제29권4호
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• pp.253-258
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• 1992

ZnO varistors were prepared by the organochemical method which used citric acid and ethylene glycol as gelling agents. The microstructure of the sintered specimens exhibited small grains, uniform grain size distribution, and few intragranular pores. Thermal decomposition of the organic resin formed during the powder preparation process was completed around 450$^{\circ}C$. No significant changes were observed in microstructure and current voltage characteristic with respect to calcination temperatures. A major advantage of the organochemical method used in this experiment is a possible uniform mixing of trace amounts of dopants. Therefore, this powder preparation method seems promising in investigating the effect of Li or In ion, which is added in ppm level to ZnO varistors, on the pulse respose characteristic.

• KSBB Journal
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• 제17권3호
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• pp.311-313
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• 2002

L. crispatus KLB46는 Gram-positive bacteria로써 인간의 건강에 중요한 역할을 한다. 본 연구에서는 glass bead를 이용하여 세포벽을 파괴하고 hot phenol RNA 분리방법을 이용하여 RNA를 성공적으로 분리하였다. 또한 Iysozyme과 proteinase K 처리과정을 배제하여 시간적, 경제적인 면에서 유용한 방법임을 확인할 수 있었다. Gram-positive bacteria에서 glass bead를 이용한 RNA 분리는 특수한 조건에 의해 전사 되거나 반감기가 찬은 mRNA의 연구에 유용한 방법이라 사료된다.

• Journal of Pharmaceutical Investigation
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• 제9권4호
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• pp.1-7
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• 1979

The analytical method of phenobarbital and mephobarbital in the pharmaceutical preparation were investigated by the partition chromatographic method. The influence of 13 kinds of excipients and various kinds of ingredients such as 8 kinds of antipyretics and 5 kinds of antacids on the partition chromatographic analysis of phenobarbital and mephobarbital in the preparation were investigated. The results were not affected by materials with the exception of caffeine, aspirin and sulpyrin.

• 한국대기환경학회지
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• 제17권4호
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• pp.363-370
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• 2001

In this study, TiO$_2$, the popular photocatalyst, was used to decompose ethanol. TiO$_2$was prepared by the sol -gel method and coated on pyrex stick. A 15W, UV-A lamp was used as the UV light source and il gas chromatography (HP 5890) was used to confirm the concentrations of ethanol, $CO_2$and the intermediates. Variation of preparation parameters and calcination temperature for TiO$_2$photocatalysts in the sol -gel method caused changes of ethanol decomposition activity. The best ethanol photodecomposition activity was obtained on the sample when prepared with 0.14 mol of HCI, a mol of ethanol and 1.3 mol of TTIP ware mixed in sol-gel process and calcinated at 50$0^{\circ}C$ for 3 hours. Acetaldehyde was detected as an intermediate and decomposed to carbon dioxide and water at the end of the reaction.

• 한국인쇄학회지
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• 제12권1호
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• pp.1.2-15
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• 1994

This is the study which appear the relation between the situation of Anchor point and the qualities of lithographic prints using the uncoated paper. Anchor point were measured by microscopic photography and Kubelka-munk`s method. The situation of Anchor point increased with print density and print though, but it decreased with evenness and rub off. In case of commercial uncoated paper, the situation of Anchor point was optimized when it was 25~35% apporoximately. In preparation of samples for microscopic photography, the samples were used by the resin testing methods. This method used that the resin fixes the printed papers of sample very hard, in preparation of samples for microscopica potography a good result could be gained by this method.

• Journal of Pharmaceutical Investigation
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• 제32권2호
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• pp.95-101
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• 2002

Matrix tablets of nifedipine (NP) were prepared with Eudragit, diluent (lactose or Ca. phosphate) and Mg. stearate employing two different preparation methods (wet granulation and direct compression) to develop its sustained-release dosage forms. The effects of various formulation factors on the dissolution rate of the drug were investigated. Dissolution test was studied in pH 6.8 phosphate buffer containing 1% sodium lauryl sulfate using the paddle method. Formulation factors were the type and content of Eudragit, the type of diluent and the tablet preparation method. The optimum formula of NP matrix tablet, which resulted in a similar dissolution profile to that from Adalat Oros used as a reference, was 30 mg NP, 10% Eudragit RS, 2% Mg. stearate and an adequate quantity of lactose to yield 500 mg weight using the wet granulation method.

• 한국식물병리학회지
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• 제14권1호
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• pp.46-51
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• 1998

A method for inoculum production of Botryosphaerisa dothidea was developed using cucumber disks and cereal media. Disks of cucumber fruits, and cereal media of barley, wheat, and rice seeds were inoculated with mycelial plugs of B. dothidea and incubated at 27$^{\circ}C$. Pycnidia were produced on the surface of cucumber disks and seeds after 5 days of inoculation. When the inoculated barley seeds were immersed in sterilized distilled water for 5 minutes, abundant conidia of B. dothidea were exuded from mature pycnidia. Conidia were held together by mucilage as they were released from an ostiole. Compared with the conventional method for inoculum preparation using agar media, such as potato-dextrose agar and oatmeal agar, this method could minimize the tedious work required for inoculum preparation within a shorter period of time.

• 한국세라믹학회지
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• 제25권6호
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• pp.671-676
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• 1988

Preparation of high purity ultrafine Ba2Ti9O20 powder was investigated by coprecipitation method. Formation of Ba2Ti9O20 powder from precipitate of coprecipitation takes place at 120$0^{\circ}C$, which is 20$0^{\circ}C$ lower than that from mechanical mixtures of BaCO3 and TiO2. This is apparently due to the nature of the compounds formed by the reaction of mixtures of aqueous solutions of BaCl2 and TiCl4 with an ammoniacal solution of ammonium carbonate and ammouium hydroxide. In this method, the Ba2Ti9O20 powders show low callcining and sintering temperature and it has good sintering and dielectric constant at room temperature.