인간적혈구의 점도와 탄성측정에 관한 실험적 연구

정경락(Gyeong rak Cheong) 전북대학교 공학연구원 (구 전북대학교 공업기술연구소) 1983 工學硏究 Vol.14 No.-

알카리 용액중 페놀파라유도체에 의한 알미늄반 부식 억제 효과

최동규(Dong Gyu Choi),김완영(Wan Young Kim),정경락(Gyeong rak Cheong),김기주(Ki Ju Kim) 전북대학교 공학연구원 (구 전북대학교 공업기술연구소) 1981 工學硏究 Vol.11 No.-

TiO_2 超微粒子의 相轉移에 관한 연구

정경락,변윤섭,김성종,장경환,양영석,정인수 전북대학교 공업기술연구소 1991 工學硏究 Vol.22 No.-

본 연구는 염소법으로 TiCl_4와 O²를 기상반응시켜 TiO²초미립자를 제조하여 생성된 Anatase 형 TiO_2를 대상으로 Anatase-Rutile의 상전이, 첨가제 및 기체 주위조건의 영향을 연구하였다. 연구결과를 요약하면 다음과 같다. 1. Anatase-Rutile의 상전이 반응에서 주된 변수는 온도이며, 속도식은 Avrami식의 결정생성과 성장모델을 따른다고 할 수 있으며, 활성화 에너지는 70kcal/mole이었다. 2. 첨가제 및 기체 주위조건의 영향에 대해서 CuO의첨가는 전이를 촉진시키는 역학을 하였으며, 진공에서는 억제시키는 것으로 나타났다. 3. Anatase형에서 Rutile형으로의 상전이 메카니즘은 Rutile핵 생성 자리가 될 수 있는 외부이온의 확산 또는 기체 주위조건의 영향에 의해 음이온 공백을 형성하고, 음이온 공백은 티타네이트 화학물을 생성한다. 이런 단계를 거치면서 Anatase형 안에서 격자결함을 유발시켜 Rutile형으로의 전이에 영향을 미치는 것이라 할 수 있다.

On the Experimental Techniques for Viscosity and Elasticity Determination of the Human Red Blood Cell

Cheong, Gyeong Rak 전북대학교 공업기술연구소 1983 工學硏究 Vol.14 No.-

암연구의 한 분야는 암세포막의 기능을 연구하는 것이다. 점도, 탄성과 같이 세포막의 물리적 성딜을 측정하여 암세포와 정상세포의 물리적 성질을 비교하고 이들 관계에서 암질환에 걸려 있는 세포막의 기능을 측정할 수 있다. 세포막의 물리적 성질을 연구하기 위하여 다음과 같이 구성되어 있는 측정장치를 설계하였다. 1. 감압장치(Negative Pressure system) 2. 마이크로 피펫트 조절장치(Micropipette manipulator) 3. 현미경(Nikon microscope) 4. 마이크로 피펫트용 도구(Micropipette Puller) 이들 장치를 이용하여 물리적 성질인 탄성과 점도를 측정 계산할 수 있다. 정상세포의 탄성계수는 8.2X10^-4dynes/cm이고 이것은 독립변수이다. 계산한 탄성치에서 두 가지 점도를 구하였다. 하나는 변형기에서 점도의 범위는 0.5X10^-4~4.0X10^-4dynes-ses/cm이고 또 하나는 회복기의 점도가0.5X10^-4dynes-ses/cm이다. 빠른 변형점도와 변형도와의 관계에서 점도는 전단변형에 의존성이라는 것을 알 수 있다.

陽이온交換樹脂의 分理性能에 關한 硏究

鄭炅樂 全北大學校 1973 論文集 Vol.15 No.-

The quantitative separation of five metals-Sodium, Karium, Lithium, Calcium, Aluminium by Amberlite IR-120 resin has been described as the following: 1. Mixing the same amount of O.IN HCI as sample metals solution, Amberlite IR-120 resin has the highest adsorption capacity for Sodium and Karium. 2. In neutral solution, Amberlite IR-120 resin has the highest adsorption capacity for Lithium. 3. When each Calcium, Aluminium sample solution has PH=2.0, PH=2.5, Amberlite IR-120 resin has the highest adsorption capacity for Calcium and Aluminium. 4. Amberlite IR-120 resin has the highest adsorption capacity for Calcium among five metals. Therefor Calcium should be adsorped selectively by Amberlite IR-120 resin.

Table Feeder의 連續定量 供給 (Ⅰ)

鄭炅樂,崔東珪,金起柱 全北大學校 1979 論文集 Vol.21 No.-

A Continuous Uniform Feeding method is studied with a modified table feeder. The table feeder examined has either two or three scrapers. Powders used in the experiment are quartz sand, talc and calcium carbonate covering a wide range of flowability. With respect to testing methods of a feeder, the effect of sampling period on the precision is studied both experimentally and thearetically. As a result, variation of precision with sampling period becomes clear even when the powder flow rate has a periodic fluctuation.

Cyclone의 傾斜角이 捕集效率과 壓力損失에 미치는 影響

鄭炅樂,金成柱,田丙寬 전북대학교 공업기술연구소 1982 工學硏究 Vol.12 No.-

Dust collection efficiencies and pressure drops of cyclones were examined concerning the tangential type cyclones under various experimental conditions-changing the inclined angle and the mean inlet velocity of cyclones. In Fig, 5~6, The experimental results can be summarized as follows : 1. for each inclined angle of the cyclone, the collection efficiency was kept comparatively regularity. But in the case of the inlet velocity over 20m/sec, the collection efficiency tends to decrease. 2. When the inclined angle change from vertical to 30˚, the influence on the collection efficiency is of no consideration. When the inclined angles are over 30˚ the collection efficiency tends to decrease a little. 3. The difference of collection efficiency for the inclined angle from vertical to 75˚ is about 4%. Therefore the influence of collection efficiency on the inclined angle of the cyclone is not significant. 4. For each inclined angle of the cyclone, the pressure drop was kept comparatively regularity. But in the case of inlet velocity over 20m/sec, the pressure drop tends to increase. 5. When the inclined angle change from vertical to 75˚, the influence of pressure drop on the inclined angles of cyclone is not significant.

化學技術情報에 대한 定期刊行物의 素引作業에 關한 硏究

鄭炅樂 全北大學校 1976 論文集 Vol.18 No.-

The uniterm card system and the termatrex card system, both based on the principle of coordinats indexing, have been analyed as specified below, along with the analysis of thesaurus as a term control descriptor. (1) The uniterm card system: merits: a. easy to use even without technical knowledge. b. inexpensive c. possible to store much information with few cards. d. mechanizable by the method of concept coordination. e. convenient as a means of storing and retrieving documents concerning single subjects. demerits: a. its user should have sufficient knowledge about the subject matters concerned to arrange various relations among uniterms and to modify word order and meanings. b. the system is complex and requires time and efforts in analyzing subject matter. c. it is difficult to store much information in smallsized cards. d. the retrieval process in complicated. (2) The termatrex card system: merits: a. the retrieval process is simple. b. information can be retrieved with little expense. c. it is easy to use. d. information retrieval takes little time. e. it is possible to select or add any indexing terms. demerits: a. the amount of information storage is limited to 100,000 items, due to the design of cards. b. The installation of input machines costs much. c. Input processes require much efforts. d. Materials cannot be retrieved directly: only their code numbers are retrieved. e. it is difficult to revise information file. f. the functions of storage and retrieval are not interrelated. (3) These systems are applicable to: a. retrieval of pattern information. b. management of research reports. c. management of (architectrual) desingns. d. management of medical research material. e. personnel management. f. management of properties and lands. g. management of information on chemical products. h. development of ready-made articles. (4) In thesaurus, the meaning, hierarchy, and connotation of terms are well specified and controlled, so the thesaurus can be valuable for the classification, storage, retrieval, and distribution of information. On the other hand, the descrpitor should be used only by those who sufficiently know how to use it, because it is too restricted to accommodate natural language. Since the uniterm card system and termatrex card system are simple, inexpensive, and practical methods of information storage and retrieval, they can be usefully adopted as means of pre-computer analysis of technical and scientific information.

TiO_2 超微粒子의 熱的 擧動에 관한 연구

정경락,변윤섭,김성종,장경환,양영석,정인수 전북대학교 공업기술연구소 1991 工學硏究 Vol.22 No.-

Anatase TiO_2 particles prepared by experiment were used to study change of crystal structure by calcination temperature. The results were as follows. Crystallite size of anatase TiO_2 particles increased with calcination temperature. The rate of increasing the crystallite size of anatas TiO_2 particles was decreased below 700℃ and was markedly increased above 700℃. Unit cell volume of TiO_2 was expanded at low temperature and was contracted at high temperature. This result means that the growth of crystallite size was occurred in the C direction.

低 濃度 化學 際染 工程에서 金屬 이온의 이온交換 特性

鄭炅樂,梁榮錫,黃成太 전북대학교 공업기술연구소 1989 工學硏究 Vol.20 No.-

Removal of metal ions in solution by use of ion exchange resin in a column is a very important step to attain high efficiency in the decontamination process. However, organic acids of the decontamination solution complex metal ions and this complexation decrease the apparent affinity of the resin toward metal ions. In light of this, some experiments were carried out on the Amberlite IRN-77 cation resin with cobalt and iron to gain a better understanding of the complexaion effects on the ion exchange process. Further, single and multi-component nonlinear equilibrium relationships of these metal ions were established and evaluation was made using experimental results.