• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.1
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• pp.50-60
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• 1998

As a method to develop an enhanced heat transfer fluid, the fine particles of a phase-change material were mixed with a conventional heat transfer fluid. Paraffin, which can be obtained easily in domestic market, was used for the phase-change material and water was used as a carrier fluid. Fine liquid particles of paraffin were formed in water as an emulsion by using an emulsifier, and they were cooled rapidly to become solid particle, resulting in paraffin slurry. The average diameter of produced solid particles was inversely proportional to the amount of the added emulsifier, which was theoretically proved. The produced paraffin slurry was tested thermally in heat transfer test section having a constant-heat-flux boundary condition. The test section was made of a circular stainless-steel pipe, which was directly heated by the power supply having a maximum of 50 Volts-500 Amperes. DSC(Differential scanning calorimeter) tests showed that two kinds of phase change were involved in the melting of paraffin, and it was explained in two different ways. A five- region-melting model was developed by extending the conventional three-region-melting model, and was used to obtain the local bulk mean temperatures of paraffin slurry in the heating test section. The local heat transfer coefficient showed a maximum where the bulk mean temperature of the paraffin slurry reached at the melting temperature of paraffin.

• Solar Energy
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• v.10 no.2
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• pp.44-58
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• 1990

Heat transfer characteristics of heat storing processes in paraffin-filled horizontal circular cylinder is studied. The unmelted solid paraffin is allowed to fall on the bottom wall under gravity. In the upper liquid phase, natural convection is considered to take place while in the lower liquid film between the solid paraffin and the wall conduction is thought to take place instead. Experimental analyses are also carried out. The amount of the latent heat stored is obtained by recording the time wisely changing side area of the solid paraffin photographically. The mass of paraffin melted in the upper section is obtained by substracting the amount of melted mass in the lower section from the total mass melted and therefrom variation of heat transfer rate in each section is studied.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.6
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• pp.888-898
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• 1998

The present study investigated the effects of the experimental parameters on the cooling characteristics of the multichip module cooled by the indirect liquid cooling method using water and paraffin slurry. The experimental parameters are mass fraction of 2.5 ~ 7.5% for paraffin slurry, heat flux of 10 ~ 40 W/cm$^{2}$ for the simulated VLSI chips and Reynolds numbers of 5,300 ~ 15,900. The apparatus consisted of test section, paraffin slurry maker, pump, constant temperature baths, flowmeter, etc. The test section made of in-line, four-row array of 12 heat sources for simulating 4 * 3 multichip module which was flush mounted on the top wall of a horizontal rectangular channel with the aspect ratio of 0.2. The inlet temperature was 20 deg. C for all experiments. The size of paraffin slurry was constant as 10 ~ 40 .mu.m befor and after the experiment. The chip surface temperatures for paraffin slurry with the mass fraction of 7.5% showed lower by 16 deg. C than those for water when the heat flux is 40 W/cm$^{2}$. The local heat transfer coefficients for the paraffin slurry with the mass fraction of 7.5% were larger by 17 ~ 25% than those for water at the first and the fourth row. The local heat transfer coefficients reached to a row-number-independent, thermally fully developed value approximately after the third row. The local Nusselt numbers at the fourth row for paraffin slurry with the mass fraction of 7.5% were larger by 23 ~ 29% than those for water.

• International Journal of Air-Conditioning and Refrigeration
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• v.9 no.1
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• pp.1-10
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• 2001

The present study investigated the effects of experimental parameters on the thermal characteristics of an in-line 6x1 array of discrete heat sources for a test multichip module using water, PF-5060 and paraffin slurry. The parameters were heat flux of 10-40W/$cm^2$. Reynolds number of 3,000~20,000 and mass fraction up to 10% for paraffin slurry The size of paraffin slurry was within 10~40$\mu$m before and after experiments. The local heat transfer coefficients for the paraffin slurry were larger than those for water. Thermally fully developed conditions were observed after the third or fourth row (five or seven times of the chip length) and the paraffin slurry showed effective cooling performance at the high heat flux The paraffin slurry with the mass fraction of 5% showed the most efficient cooling performance when the heat transfer and the pressure drop in the test section are considered simultaneously. The experimental data at the fourth and sixth rows are best agreed with the values predicted by the Malina and Sparrow`s correlation among other correlations, and the empirical correlations for water and 5% paraffin slurry were obtained at the first and sixth rows when the channel Reynolds number is over 3,000.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.12
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• pp.1275-1281
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• 2001

Aqueous polymer solutions are known to have small pressure reduction. Paraffin slurries are known to have high thermal capacity. Paraffin particles are mixed into an aqueous polymer solution to make a new heat transfer fluid having high thermal capacity but low pressure reduction. The heat transfer characteristics of the new slurry was tested in a circular tube having a constant heat transfer boundary condition. The new slurry was found to have high Nusselt numbers as well as high thermal capacity and low pressure reduction in the laminar flow. The trends of the Nusselt numbers along the heating test section were studied for various heating conditions.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.1953-1956
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• 2012

Objective: The purpose of this study was to correlate the histological diagnosis made during intraoperative frozen section (FS) examination of hysterectomy samples with complex atypical endometrial hyperplasia (CAEH) diagnosed with definitive paraffin block histology. Methods: FS pathology results of 125 patients with a preoperative biopsy showing CAEH were compared retrospectively with paraffin block pathology findings. Results: Paraffin block results were consistent with FS in 78 of 125 patients (62.4%). The FS sensitivity and specificity of detecting cancer were 81.1% and 97.9%, with negative and positive predictive values of 76.7%, and 98.4%, respectively. Paraffin block results were reported as endometrial cancer in 77 of 125 (61.6%) patients. Final pathology was endometrial cancer in 45.3% patients diagnosed at our center and 76.9% for patients who had their diagnosis at other clinics (p=0.018). Paraffin block results were consistent with FS in 62.4% of all cases Consistence was 98.4% in patients who had endometrial cancer in FS. Conclusion: FS does not exclude the possibility of endometrial cancer in patients with the preoperative diagnosis of CAEH. In addition, sufficient endometrial sampling is important for an accurate diagnosis.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2119-2123
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• 2007

This study deals with performance characteristics of heat pipe combined with a solid-liquid phase change material(PCM). The outer diameter of the heat pipe was 9.5 mm and the total length was 600 mm, where the evaporator, the adiabatic section and the condenser lengths were equally 200 mm. A paraffin wax having a melting point of 58.5$^{\circ}C$ was used as PCM. The paraffin container was attached to the adiabatic section of the heat pipe. The paraffin container had outer diameter of 18 mm, wall thickness of 1.2 mm and the total length of 100 mm. The heat pipe was tested with tilt angle of horizontal degree and favorite angle 10 degree, with evaporator lower position to provide stable operation of the heat pipe. Input thermal load was varied from 40 W, with increment of 40 W, to above 100 W until the maximum temperature of the heat pipe wall reached 200$^{\circ}C$. Test results of the PCM heat pipe were presented in comparison with conventional heat pipe of the same basic dimensions. The performance was analyzed in terms of temperature distribution, thermal resistance and heat transport capability.

• Biomedical Science Letters
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• v.8 no.3
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• pp.161-165
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• 2002

Apoptosis can be difficult to detect in routine histological sections. Since extensive DNA fragmentation is an important characteristic of this process, visualization of DNA breaks could greatly facilitate the identification of apoptotic cells. Several techniques for the qualitative and quantitative detection of this process have been established; recently, an in situ nick end-labelling technique based on the detection of DNA fragmentation, which is a molecular characteristic of apoptotic cell death, was described. Applying this method to paraffin sections of rat tissues, sensitivity was observed to be inconsistently low with regard to the expected number of apoptotic cells. I describe a new modified method for formalin-fixed, paraffin-embedded tissue sections, pretense pretreatment to permeate the tissue sections that involves an TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling) is acknowledged as a method of choice in the rapid identification and quantification of the apoptotic cell fraction in paraffin tissue preparations. TUNEL was performed without apoptosis and with apopotosis samples to each of the three concentrations of proteinase K (10, 25, 40 mg/ml) pretreatments. In this study, I show that chemical pretreatments of the tissue sections in proteinase K (25 mg/ml for 15 min at room temperature) considerably enhances the sensitivity of this nick end labelling technique.

• Korean Journal of Veterinary Research
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• v.33 no.2
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• pp.255-261
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• 1993

For a immunohistochemical diagnosis of the frozen and paraffin-embedded tissues against rabies virus, mice were intracerebrally inoculated with challege virus standard(CVS) rabies virus and then were used to detect the rabies viral antigen by the immunoperoxidase(IP) and the avidin-biotin complex(ABC) method. In this study, the results confirmed that ABC and IP methods, although the former showed more specific and sensitive than the latter, were reliable and effective for the demonstration of rabies virus in both frozen and paraffin-embedded brain tissues prepared from rabies-infected mice. Additionally, IP technique using the monoclonal antibody against rabies virus could be recommended as a standard diagnostic tool instead of the present immunofluorescent method for the local veterinary services in Korea.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2657-2662
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• 2013

Background: Intraoperative sentinel lymph node biopsy has now become the standard of care for patients with clinically node negative breast cancer for diagnosis and also in order to determine the need for immediate axillary clearance. Several large scale studies confirmed the diagnostic reliability of this method. However, micrometastases are frequently missed on frozen sections. Recent studies showed that both disease free interval and overall survival are significantly affected by the presence of micrometastatic disease. The aim of this study was to determine the sensitivity and specificity of intraoperative frozen section analysis of sentinel lymph nodes (SLNs) for the detection of breast cancer micrometastasis and to evaluate the status of non-sentinel lymph nodes (non-SLNs) in those patients subjected to further axillary sampling. Materials and Methods: We performed a retrospective study on 154 patients who underwent SLN biopsy from January 2008 till October 2011. The SLNs were sectioned at 2 mm intervals and submitted entirely for frozen sections. Three levels of each section submitted are examined and the results were compared with further levels on paraffin sections. Results: Overall 40% of patients (62/154) were found to be SLN positive on final (paraffin section) histology, out of which 44 demonstrated macrometastases (>2mm) and 18 micrometastases (<2mm). The overall sensitivity and specificity of frozen section analysis of SLN for the detection of macrometastasis was found to be 100% while those for micrometastasis were 33.3% and 100%, respectively. Moreover 20% of patients who had micrometastases in SLN had positive non-SLNs on final histology. Conclusions: Frozen section analysis of SLNs lacks sufficient accuracy to rule out micrometastasis by current protocols. Therefore these need to be revised in order to pick up micrometastasis which appears to have clinical significance. We suggest that this can be achieved by examining more step sections of blocks.