• Korean journal of food and cookery science
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• v.9 no.4
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• pp.289-292
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• 1993

The effect of sugar alcohols in the preparation of acceptable low methoxyl pectin(LMP) jellies were studied. Sensory scores analysis, Hunter's color parameters and texture profile analysis using universal testing machine were performed. The composition of sweetners used in this study were 100％ sucrose, 75％ sucrose and 25％ maltitol, 50％ sucrose and 50％ maltitol, and 50% sucrose, 25％ maltitol, 12.5％ sorbitol'and 12.5% mannitol. LMP jellies with 100％ sucrose showed the strongest sweetness among them. Other sensory characteristics of LMP jellies were regarded as same. Hunter's value of lightness, redness and yellowness of 100％ sucrose jellies and jellies substituted with maltitol up to 25％ were not significantly different, but those of LMP jellies substituted with 50％ sugar alcohols were higher(p<0.01) than other 3 types of jellies. As substitution ratio was increased, springiness and chewiness were lower(p<0.01). Fracturability(p<0.01) and hardness(p<0.05) of jellies made of 100% sucrose and 75％, sucrose and 25% maltitol showed higer value than the other jellies. Springiness of jelles sweetened with sucrose and 3 sugar alcohols was the highest(p<0.05). Replacement of sucrose by sugar alcohol did not influenced on gumminess and cohesiveness of LMP jellies.

• Journal of the Korean Wood Science and Technology
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• v.41 no.3
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• pp.181-186
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• 2013

In this work, charcoal making characteristics of Quercus phyllyaeoides (which has been known as one of best raw materials for charcoals) was investigated. Charcoal from Quercus phyllyaeoides had more than 85% of fixed carbon, which is 5~25% higher fixed carbon content than other charcoals. Also specific gravity of this charcoal was more than 1.0, which is quite higher than other black charcoals (average of commercial products: 0.52) or white charcoals (average of commercial products: 0.73). Methylene blue adsorption, pH, and adsorption of water vapour was lower than other commercial charcoals. Carolic value of this charcoal was similar to other commercial products. Far infrared ray's emission from this charcoal was higher than others. Application of charcoal from Quercus phyllyaeoides should be consider the characteristics of this product.

• Journal of Korea Foresty Energy
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• v.25 no.1
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• pp.9-17
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• 2006

Properties of wood charcoal made from the domestic wood species at $300-900^{\circ}C$ have investigated to understand the correlation between carbonization temperature and chemical and physical characteristics of wood charcoal. In terms of charcoal yield at particular carbonization temperatures, it was drastically decreased until the temperature reaches up to $600^{\circ}C$ and the decrease ratio of yield was reduced at higher temperatures. As the carbonization temperature increased, pH of the wood charcoal increased so that it became basic at last. The wood charcoal prepared at $600{\sim}700^{\circ}C$ showed the highest caloric value and those of wood charcoals made at higher temperature became plateau at a little lower level than the peak. The caloric value of Japanese larch charcoal was a bit higher than that of Red oak charcoal. The carbon content in the wood charcoal was increased as the carbonization temperature increased, whereas the hydrogen content was decreased. Specific surface area of the wood charcoal became larger with increase in temperature up to $600^{\circ}C$ but it was decreased or reduced in the increasing ratio after, and then it rose again at higher temperature than $800^{\circ}C$. Absorption capacity of the wood charcoal against iodine and gaseous acetic acid became greater as the carbonization temperature increased. Japanese larch charcoal presented higher absorption capacity than Red oak charcoal. As the above results, it is revealed that carbonization temperature affects the chemical and physical properties of wood charcoal. Therefore, to use wood charcoal with maximum effect it should be prepared at optimum temperature for proper use.

• Fire Science and Engineering
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• v.22 no.1
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• pp.99-104
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• 2008

It is important to understand thermal characteristic as a method to estimate the new materials, because spontaneous ignition characterized by causing combustion in the low temperature without ignition source. If can not find out the thermal characteristics of materials, it is frequent that causes of fires could not be found. The danger level of spontaneous ignition material should be estimated and by closely studying its thermal characteristic. However, RPF(Refuse Paper & Plastic Fuel) is a solid matter and getting increasesa year by year because it is an economy profit as alternative energy for limited fossil fuels. Some time RPF occur a fire in the cases of its production process and conservation. Therefore study for thermal stability and critical ignition temperature of RPF was so imperative that the experiment by means of Bombe Calorimeter, TG-DTA, MS80, SIT-II, and Wire Basket Test was implemented. As a result, RPF had a caloric value 26.4-28.3 MJ/kg, and its initial pyrolysis temperature was $192^{\circ}C$ at heating rate 2 K/min. With the result of analysis by MS 80 which is an instrument measuring microscopic calory, pure RPF not containing water has higher caloric value than RPF containing 20% water. Also, SIT-II which is an instrument of insulated auto-ignition was ignited by $118.5^{\circ}C$. This temperature is lower than that of Wire Basket Test. The critical ignition temperature was calculated by Frank-Kamenetskii equation can cause ignition at $80^{\circ}C$ when conserved in the height of 10 m by the standard of infinity slab.

• Applied Chemistry for Engineering
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• v.22 no.2
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• pp.155-160
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• 2011

An animal fat is an attractive biodiesel energy source for its high stability against oxidation and low incomplete combustion ratio due to the high heating value and cetane value. However, it requires a refinery process because of the high content of saturated acid and impurity which increas the boiling point. In this study, the optimum biodiesel synthetic process of lard is suggested. Indeed, we demonstrate new biodiesel production processes to alter conventional process of heating and mixing by applying ultrasonic energy. While the optimum reaction temperature and mole ratio of methanol and lard, when using conventional mixing and heating process, were $55^{\circ}C$ and 12, respectively, the reaction time were reduced to 30 minutes by applying ultrasonic irradiation power of 500 W. The new process applying ultrasonic irradiation yielded synthetic biodiesel properties as followings: 3.34 cP of the viscosity, 37.0 MJ/kg of the caloric value and below 0.25 mgKOH/g of the acidic value, which satisfy biodiesel quality criteria.

• Journal of Environmental Health Sciences
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• v.12 no.2
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• pp.49-66
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• 1986

The purpose of this study was to investigate nutrition intake of high school girls related to food habit, physical status, family environmental factor. The survey of 216 high school girls, aged 15 to 17 years old in Seoul area was conducted from April, 21 to 30, 1986. Food habit and family environmental factor were researched by means of questionnaires and nutrition intake was surveyed. by recording the kinds, amounts and ingredients of foods taken by the girls for two days, and height and weight were also measured during the period. The findings are summarized as follows: 1. Mean value of height and weight of the girls were 157.6cm and 50.9kg. 2. Number of family members per household was 5.2. Mean value of father's age was 47.1 and mean value of mother's age was 43.6. 44.9% of the girls had fathers who graduated the college, 41.6% of the girls had mothers who graduated the high school and 29.2% of the girls had mothers who had the job. 3. Breakfast missing rate was high, most of the reason for breakfast missing was 'have no time to eat' and time for breakfast was short. 64.4% of the girls had meal irregularly. 4. Mean daily intake of all nutrients except vitamin A and riboflavin was higher than Recommended Dietary Allowances. Mean caloric intake was 89.8% of R.D.A.. Breakfast intake of energy and most of nutrients was less than snack. Mean meal balance score was 47.9 and mean food diversity score was 13.4. 5. Mother's education level was related to intake of protein and calcium and height. Breakfast and lunch missing and number of snack intake were related with nutrition intake.

• Journal of the Korea Organic Resources Recycling Association
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• v.18 no.3
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• pp.60-67
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• 2010

Korea's large-scale incinerating facilities of domestic waste were built in the late 1980's. It was found that most of the incinerators were designed during the period and even the ones constructed afterwards have been built without any changes or modifications. However, the nature of waste fed into incinerators is undergoing a radical change due to government policies on waste collection, which is upheld by a research into changes in the heating value of domestic wastes. As a result, refractories and stokers are being damaged in many of the facilities due to overheating. On the other hand, the formation of clinkers on boilers' heating surface, which curbs he at transfer, results in problems such as a fall in used heating value and a rise in the temperature of combustion chambers. Methods are being deployed to resolve the problems-such as spraying water on piles of waste, incinerating food waste by mixing together what has been separately collected, spraying water on combustion chambers, etc. Such actions are not a fundamental solution, nor redesigning and rebuilding incineration facilities is cost-effective. This research seeks to develop a fundamental solution to address the situation.

• Journal of Industrial Technology
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• v.17
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• pp.37-42
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• 1997

Generation and physico-chemical characteristics of municipal solid wastes are very important for sanitary management. However, that has not been investigated so far especially in chunchon. And so, we tried to examine many things in detail. It was resulted that density was $90{\sim}94kg/m^3$ in school and office zone and $290{\sim}298kg/m^3$ in apartment and market place. The compositional weight fraction was food, 40~54%, paper, 14~18%, vinyl and prastic, 14~20% in house zone and market place and paper, 42~70% in school and office zone. Moisture was estimated to be 54~57% in independent house zone, apartment and market place and 11~23% in school and office zone. And three composition was water content, 44.1%, incineration particle, 11.2%, volatile parts, 44.7% in respectively. That is because of seasonal effects and regional chracteristics. In the results of chemical composition and caloric value analysis, carbon(C) was 80% in vinyl and plastic and oxygen(O) was 54.4% in paper.

• The Korean Journal of Physiology
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• v.4 no.2
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• pp.69-81
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• 1970

These studies were carried out on 176 persons ranging in age from 20 to 50 years to determine the basal metabolic rates, energy expenditure of various activities, and daily energy expenditure of service personnel in Korea. The measurements of basal metabolic rates were made on 42 subjects by indirect calorimetry using a Douglas' bag and Scholander's gas analyzer. The energy expenditures of various activities of daily life were also measured. The greatest increase in ratio of energy expenditure in the basis of resting metabolism was 277.3% in floor sopping and the least was 40.9% during hair cutting by beauticians. The assessment of the dailly energy expenditure for each subject was made by the factorial method, using a record of their activities throughout each of 24 hours of every survey day. Certain activities were recorded in minute units. The total daily energy expenditure is the sum of all energy expenditure. This was calculated by multiplying the caloric value of the metabolic rate by the time spent on each activity. The result of the total daily energy expenditure records for 17 occupations are summarized. In respect to the daily energy expenditure, most of the occupations are moderate or light work. But the janiter (F), laundress, cook (F), room maid and nurse's aid do heavy work.

• Journal of the Korean Wood Science and Technology
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• v.45 no.6
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• pp.671-681
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• 2017

Oil palm trunk (OPT) is a potential source of biomass for the production of biopellet. In the present research, biopellet were prepared from the meristem part of 25 years old OPT with various percentages of its bark (0, 10, and 30%). The highest biopellet durability was found for biopellet produced at $130^{\circ}C$ of pelletizing temperature with 30% bark content. Scanning electron microscopy (SEM) of biopellet showed the weak of particle bonding due to the low pelletizing pressure. The moisture content, unit density, ash content, and caloric value of OPT-based pellets were 3.55-5.35%, $525.56-855.23kg/m^3$, 2.76-3.44%, and 17.89-19.14 MJ/kg, respectively. The combustion profiles obtained by thermogravimetric analysis (TGA) seemed to be unaffected by the bark content on. Differential thermal analysis of TGA curve indicated different pyrolysis characteristic of hemicellulose, cellulose, and lignin.