• Title/Summary/Keyword: Physical condition

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An Effect of the Self-Regulation Program for Hypertensives -Synthesis & testing of Orem and Bandura's theory- (본태성 고혈압 환자의 자가간호증진을 위한 자기조절 프로그램 효과 -Orem이론과 Bandura이론의 합성과 검증-)

  • Park, Young-Im;Hong, Yeo-Shin
    • Research in Community and Public Health Nursing
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    • v.5 no.2
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    • pp.109-129
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    • 1994
  • Chronic health problems has become a major concern and challenge to the health care professionals today. Especially hypertension, one of the leading primary cause of death in Korea, is a typical chronic disease requiring adequate and continuous management. Though these hypertensives need to maintain desirable health practice by themselves for their life time, many previous studies indicated that most of the essential hypertensives have no specific symptoms and thus, reluctant to follow appropriate medical regimens causing the condition further aggravated and complicated. Self-care is an essential factor that keeps chronic patients in control of their health and wellness. Thus this study was conducted to identify the effect of the comprehensive self-regulation program as a nursing intervention on the promotion self-care performance and improvement in physical parameters of hypertensives. For this purpose, a one group quasi-experimental research with pre and post test design was used. The subjects of the study was consisted of thirty persons with mild or moderate essential hypertension from two companies in Cheong-ju city. The whole program was carried out from October, 1993 to February, 1994. The self-regulation program was consisted with group education on hypertension and self-care, self-regulation including the blood pressure self-monitoring and recording, recording of daily self-care activities, and encouraging and reinforcing self-efficacy through verbal persuation and enactive attainment. The subjects were asked to measure their own blood pressure by themselves twice per day and to record blood pressure and the daily self-care performance according to the instructions provided during the whole period of 9 weeks. The instruments used for data collection in this study were as follows : 1) Instruments used for measuring the knowledge about hypertension, multiple health locus of control, and perceived benifits and barriers were adapted from previous studies and modified by author to be fit for the subjects. 2) Self-efficacy scale and self-care performance record were developed by the author. 3) Physiological parameters included systolic / diastolic blood pressure, body weight, level of blood cholesterol, and 24hour ambulatory blood pressure. The post-experimental Cronbach's Alpha as the reliability test of scales were 0.703-0.897, an appropriate level of confidence. The effect of the program was analyzed by experimental stages ; the first week, the fifth week, and the ninth week since the experimental imput began. Data were analyzed by the SPSS PC+ program with paired t-test and t-test, repeated measure ANOVA, and pearson's correlation to de termine the effect of program. The results were as follows : 1) After the self-regulation program, scores on knowledge(t=-2.41, p=.011), perceived self-efficacy (F=5.60, p=.001), self-care performance(F=22.31, p=.0001) were significantly higher than those before the program. 2) After the program, both systolic and diastolic blood pressure were significantly lower than those before the program(F=10.89 -13.11, p=.0001). However in 24hour ambulatory blood pressure, systolic mean pressure was nearly significantly lower, but not in diastolic mean pressure. 3) After the program, the body weight was significant decresed(t=5.53, p=.0001), but the blood cholesterol level was not decreased significantly except in those cases with higher cholesterol level. 4) There were significant relationships between changes in self-care performance and diastolic pressure at 1st week (r=.3389, p=.033) and changes in self-care performance and systolic pressure at 9th week(r=.3651, p=.024). 5) There were significant relationship between perceived self-efficacy and self-care performance at 5th week(r=.5313, p=.001) and 9th week (r=.3026, p=.052). 6) After the program, internal health locus of control and perceived benefits did not show significant change, but perceived barriers was significantly lower than those before the program (t=3.57, p=.0001). From the above results, it can be concluded that 1) The self-regulation program is an effective nursing strategy to promote self-care performance of hypertensives and to lower the blood pressure. Thus this program can be recommended in the management of the hypertensives in workplaces and community settings. 2) The synthesis of Orem's self-care theory and Bandura's self-regulation & self-efficacy theory in this study was proved to enhance explanation and prediction of the change of self-care behavior. Thus the result of the study would contribute in development of the self-care theory and an expansion of practice-theory.

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Characteristics of Titanium Dioxide-Impregnated Fibrous Activated Carbon and Its Application for Odorous Pollutant (이산화티타늄 담지 섬유형 활성탄소의 특성 및 악취오염물질 제어를 위한 응용)

  • Jo, Wan-Kuen;Hwang, Eun-Song;Yang, Sung-Bong
    • Clean Technology
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    • v.17 no.1
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    • pp.48-55
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    • 2011
  • The application of fibrous activated carbon (FAC)-titanium dioxide ($TiO_2$) hybrid system has not been reported yet for the control of malodorous dimethyl sulfide (DMS) at residential environmental levels. Accordingly, the current study was designed not only to characterize this hybrid system using x-ray diffraction method, particulate surface measurement and Fourier transform Infrared (FTIR) method, but also to evaluate its adsorptional photocatalytic activity (APA) for the DMS removal. The physical/surface characteristics of FAC-$TiO_2$ which was prepared in this study suggested that the hybrid material might have certain APA for DMS. The Brunauer-Emmett-Teller (BET) specific area, total pore volume, micropore volume and mesopore volume decreased all as the $TiO_2$ amounts coated on FAC increased, whereas the reverse was true for average pore diameter. $TiO_2$ coated onto FAC did not influence the adsorptional activity of FAC for the DMS input concentration of 0.5 ppm. The APA test of the hybrid material presented that the initial removal efficiencies of DMS were 93, 78, 71 and 57% for the flow rates of 0.5, 1.0, l.5 and 2.0 L/min, respectively, and they decreased somewhat 2 h after the experiment started and kept almost constant for the rest experimental period. Under this pseudo-equilibrium condition, the DMS removal efficiencies were 78, 58, 53 and 36% for the four flow rates, respectively. Meanwhile, there were no significant byproducts observed on the surfaces of the hybrid material. Consequently, this study suggests that, under the experimental conditions used in the present study, the hybrid material can be applied for DMS at residential environment levels without being interfered by any byproducts.

CLINICAL CHARACTERISTICS AND TREATMENT COURSES OF THE CHILDREN WITH SELECTIVE MUTISM (선택적 함구증 아동의 임상특성 및 치료경과)

  • Chung, Sun-Ju;Hong, Kang-E
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.6 no.1
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    • pp.74-89
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    • 1995
  • Selective mutism is a childhood condition defined by persisten failure to speak in specific social situation when speaking is expected, dispite preserved ability to comprehend spoken language and speak. Present study is to investigate clinical characteristics, treatment method and outcome of 23 children who were diagnosed as selective mutism by DSM-IV criteria at the child psychiatry ouptatient department of SNUH. The results were as follows : 1) The Sex ratio was 1: 4.8, female dominant Mear age of onset was 33 years old and mean age of first referral was 7.7 years old. 2) 22% of subjects had perinatal problem such as low birth weight, preterm birth, 26% of the subjects have history of delayed language development. There are subjects who had been separated with mam caretaker before 3 years old(26%) and who experienced physical or psychological trauma before 3 years old(26%). A few subjects had enurests(30%) and encoprests(4%). 3) Many subjects(65%) had symbiotic relationship with their mother. These families consist of dominant, verbally aggressive mother and passive father. Parents of 39% of all subjects were judged to have definite psychopathology(social phobic, depression, hysterical trait or alcohol problem) 26% of all subject, were reported physically abused. 4) The personality trait of the subjects were frequently described as follows(in order of frequency) ; Shy(100%), anxious(83%), stubborn(83%)m rigid and tense posture(78%), immature(65%) overdependent(65%), irritable(52%), manipulative(39%), depressive(39%). 5) The mean performance IQ of 16 subjects by KEDI-WISC was 88.3 Among them, the subjects with IQ below 69 were seven and those with IQ above 70 were nine. When comparing these two group(Mental retardation group vs Normal IQ group), we could find some difference in language development, personality trait, family dynamics and treatment outcome. 6) Among several treatment methods for selective mutism, play therapy was the most frequently used method(65%). Other commonly used treatment methods were pharmacotherapy(21%), behavioral therapy(8%), combined therapy(play therapy+pharmacotherapy+family therapy+behavioral therapy)(12%), 7) Regarding the outcome of treatment 8.6% was evaluated as Excellent, 30.4% as Good, 52% as Fair, 8.7% as Poor at the tinic of treatment. At follow up interview 21.7% was evaluated Excellent, 13% as Good, 21.7% as Fair, 34.8% as Poor. 8) We classified all subjects by Havden's 4 subtype. Symbiotic mutism was most common(65%) and other subtypes are Speech phobic mutism(8.6), Reactive mutism(13%) and Passive-aggressive mutism(30%).

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Physicochemical Characteristics and Varietal Improvement Related to Palatability of Cooked Rice or Suitability to Food Processing in Rice (쌀 식미 및 가공적성에 관련된 이화학적 특성)

  • 최해춘
    • Proceedings of the Korean Journal of Food and Nutrition Conference
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    • 2001.12a
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    • pp.39-74
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    • 2001
  • The endeavors enhancing the grain quality of high-yielding japonica rice were steadily continued during 1980s∼1990s along with the self-sufficiency of rice production and the increasing demands of high-quality rices. During this time, considerably great, progress and success was obtained in development of high-quality japonica cultivars and qualify evaluation techniques including the elucidation of interrelationship between the physicochemical properties of rice grain and the physical or palatability components of cooked rice. In 1990s, some high-quality japonica rice caltivars and special rices adaptable for food processing such as large kernel, chalky endosperm aromatic and colored rices were developed and its objective preference and utility was also examined by a palatability meter, rapid-visco analyzer and texture analyzer. The water uptake rate and the maximum water absorption ratio showed significantly negative correlations with the K/Mg ratio and alkali digestion value(ADV) of milled rice. The rice materials showing the higher amount of hot water absorption exhibited the larger volume expansion of cooked rice. The harder rices with lower moisture content revealed the higher rate of water uptake at twenty minutes after soaking and the higher ratio of maximum water uptake under the room temperature condition. These water uptake characteristics were not associated with the protein and amylose contents of milled rice and the palatability of cooked rice. The water/rice ratio (in w/w basis) for optimum cooking was averaged to 1.52 in dry milled rices (12% wet basis) with varietal range from 1.45 to 1.61 and the expansion ratio of milled rice after proper boiling was average to 2.63(in v/v basis). The major physicochemical components of rice grain associated with the palatability of cooked rice were examined using japonica rice materials showing narrow varietal variation in grain size and shape, alkali digestibility, gel consistency, amylose and protein contents, but considerable difference in appearance and torture of cooked rice. The glossiness or gross palatability score of cooked rice were closely associated with the peak. hot paste and consistency viscosities of viscogram with year difference. The high-quality rice variety “Ilpumbyeo” showed less portion of amylose on the outer layer of milled rice grain and less and slower change in iodine blue value of extracted paste during twenty minutes of boiling. This highly palatable rice also exhibited very fine net structure in outer layer and fine-spongy and well-swollen shape of gelatinized starch granules in inner layer and core of cooked rice kernel compared with the poor palatable rice through image of scanning electronic mcroscope. Gross sensory score of cooked rice could be estimated by multiple linear regression formula, deduced from relationship between rice quality components mentioned above and eating quality of cooked rice, with high Probability of determination. The ${\alpha}$ -amylose-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were Ilpumbyeo, Chucheongbyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tongil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, shelved the relatively fast deterioration of cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogiadation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked rice. The softer gel consistency and lower amylose content in milled rice revealed the higher ratio of popped rice and larger bulk density of popping. The stronger hardness of rice grain showed relatively higher ratio of popping and the more chalky or less translucent rice exhibited the lower ratio of intact popped brown rice. The potassium and magnesium contents of milled rice were negatively associated with gross score of noodle making mixed with wheat flour in half and the better rice for noodle making revealed relatively less amount of solid extraction during boiling. The more volume expansion of batters for making brown rice bread resulted the better loaf formation and more springiness in rice bread. The higher protein rices produced relatively the more moist white rice bread. The springiness of rice bread was also significantly correlated with high amylose content and hard gel consistency. The completely chalky and large gram rices showed better suitability for fermentation and brewing. Our breeding efforts on rice quality improvement for the future should focus on enhancement of palatability of cooked rice and marketing qualify as well as the diversification in morphological and physicochemical characteristics of rice grain for various value-added rice food processings.

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The Effect of Intradermal Acupuncture on The Patients suffering from Insomnia after Stroke (중풍환자(中風患者)의 불면증(不眠症)에 피내침(皮內針)의 유효성(有效性) 및 적응증(適應證) 평가(評價))

  • Lee Sang-Ho;Kim Eun-Ju;Kim Lee-Dong;Yun Sang-Pil;Lee Cha-Ro;Hong Jin-Woo;Jeong Dong-Won;Moon Sang-Kwan;Cho Ki-Ho;Kim Young-Suk
    • The Journal of Internal Korean Medicine
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    • v.25 no.1
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    • pp.138-148
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    • 2004
  • Objective : Insomnia is the disorder of initiation or maintenance in sleeping that results in daytime sleepiness and dysfunction, and it arises from multiple psychological, physiological and environmental factors. A number of stroke patients suffer from insomnia are classified as sleep disorder patients with physical illness. In addition, insomnia may have profound deleterious effects on the natural course of stroke. We are to assess the effectiveness of intradermal acupucture on stroke combined with insomnia. Methods : We recruited hospitalized patients with insomnia after stroke. Then, the subjects were allocated into a treatment group and a control group by randomization. The treatment group received intradermal acupuncture therapy at He-7(神門), EH-6(內關) correctly. However in control group, intradermal acupuncture were just attached to He-7(神門), EH-6(內關) without insertion. Treatment over time at first day and second day a various indexes were repeatedly checked such as sleep latency, total sleep time, sleep quality, condition on awakening, ability of concentration, morning sleepiness, Insomnia Severity Index, and Athens Insomnia Scale. In the second analysis, we divided the treatment group into a response and a non-response group by their response to intradermal acupuncture. With the acupuncture treatment, accompanied symptoms were checked Results : Among thirty two subjects, two of them were dropped out: One complained the pain from needle insertion, and the other underwent the change of his herbal medication. At baseline investigation with the residual 30 subjects, the control and the treatment group were assessed to have an equal comparability. In the treatment group, sleep latency, total sleeping time, a number of awakenings, sleep quality and ability of concentration showed improvement significantly compared with the control group. The non-response Group showed symptoms such as nausea and halitosis, belching and acid regurgitation, abundant expectoration, while Responder Group showed palpitation, oppressed feelings in chest and sleep disorder. Conclusions: The result of this clinical study suggests that the intradermal acupuncture at He-7(神門), EH-6(內關) is one of the effective treatments for the insomnia after stroke.

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The review on the identification of the gifted child in the sports (스포츠영재의 판별에 관한 고찰)

  • 신승윤
    • Journal of Gifted/Talented Education
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    • v.11 no.1
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    • pp.81-98
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    • 2001
  • The purpose of this study was to indicate the ways to identify the gifted child in the sports, and the research direction in this area in the future. The most of researches related to the early development of the children who showed the gifted talents in the certain sports skills were published from the European area such as the old East Germany or Soviet Union. Those research papers or articles were main focus of this study to be analyzed. The analysis in this study will be assistant to provide the direction of the research in the future about the method to identify appropriately on the children with the gifted sports skills. -Related to the period of selection of the children with sports skill gifted, the divided selection procedure will be good such as the 1st selection and 2nd selection. In the 1st selection, the goal will be to test the potentials of the children with the sports talents in the public school with creating the special group, and the 2nd selection will be to examine the qualification of the admission to the special schools for the children with the sports talents. -Related to the method of selection of the children with sports talents, the special item on the developmental procedure should be considered on the each field as well as the potentials focused. And, the physical factors, the condition of growth and development, psychological factor, and environmental factor should be comprehensively considered. -The system of promotion in the period of the primary school will be appropriate in the special group for the children with the sports talents, and the special school will be good from the middle school. The system outlooks will be adequate if shaped as the hierarchical structure. -The curriculum for the children with the sports talents will be proper that the basic fitness for the earlier ages and the professional skills will be recommended if getting older. -The continuous research is strongly required for the judgement and promotion of the children with sports talents, therefore, the multiple intelligences approach will be helpful for the development of the bodily-kinesthetic intelligence, and in other words, the new era of the genetic method will be another prospective area such as the DNA analysis in the identification of the talented children for the sports filed.

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A Study on Woman's Experience of Being Bereaved of Her Husband by an Accident (사고로 남편을 잃은 여성의 경험)

  • Park, Sung-Hark;Choi, Mi-Hye;Chung, Yeon-Kang
    • Research in Community and Public Health Nursing
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    • v.7 no.2
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    • pp.294-312
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    • 1996
  • Relatively young widows, who are left with young children by a sudden death of their husbands, will be faced with not only psychological troubles such as individual anxiety and frustration but also the dual burden of playing both father and mother roles in a family, Also, family members have difficulty in adapting themselves to new circumstances of the family system, the training and raising of family members, and management of the family economy. In this study, the realistic resources on the experience of middle-aged women who are bereaved of their husbands by accidents were explored. The purpose of this study is to help widows adapt to life in society and live a more positive life by setting a new goals and recovering from a lost and twisted life. 11 women, who have experienced the loss their husbands and live in the Seoul metropolitan area were studied. The research took 116 days from December 15, 1995 to April 8, 1996. The method of research was direct interviews. While having interviews with them, the contents were recorded with their consent. The ground theory was that used by Strauss & Corbin(1990) in the analysis of the data. 81 concepts were analyzed and they were subdirided into 22 subordinate categories through the course of the analysis. These were then classified into 9 general categories. In the course of being categorized, 'absurdity' was showed as a core category. The subordinate categories 'surprise', 'gloom', 'grudge', 'helplessness', 'emptiness', and 'loss' were united in the core category 'absurdity'. Ominous presentiment, belated notice, death, surprise, gloom, grudge, helplessness, emptiness, loss, the situation of the children, lack of support from neighbors, support from neighbors, mulling over ways to live, choosing a job, strengthening, reinforcement, burden, sadness, smoldering, yearning, overcoming these 22 subordinate categories were re-composed into 9 general ones the husband's death, absurdity, presence of children, existence of support, self-support ability, preparation of countermeasures, self-reinforcement, toilsomeness, and overcoming. 'Absurdity' widows experience was shown in the results of 'toilsomeness' and 'overcoming' through reaction, confrontation, and adaptation. According to the analysis the central phenomenon was absurdity, the causal condition of the death of a husband, the presence of children and the existence of support, and the meditated situation of self-support. To solve absurdity, the preparation of countermeasures and self-reinforcements were shown resulting in toilsomeness and overcoming. Through the contrast in the data, the following statements were deduced: (1) If the death of the husband is expected, the more a widow will feel absurdity. (2) The more children she has and the younger she is, the more a widow will feel absurdity. (3) The lower support she is given, the more a widow will feel absurdity. (4) The larger self-ability she has, the more actively she will prepare countermeasures. (5) The smaller self-ability she has, the more passively she will prepare countermeasures. (6) The larger self-ability she has, the weaker self-reinforcement she will preform. (7) The smaller self-ability she has, the stronger self-reinforcement she will perform. (8) The more actively she prepares countermeasures for absurdity, the better she will overcome. (9) The more passively she prepares counter measure for absurdity, the worse she will overcome. (10) The stronger self-reinforcement for absurdity she performs, the better she will overcome. (11) The weaker self-reinforcement for absurdity she performs, the worse she will overcome. Through the results in this study, the following suggested: 1) A study whose object is all family members, and a comparative study on the case of a husband who has lost his wife should be done. These studies can be expected to develop a more refined theory. 2) Because of the collapse of the extended family system and the changes of family culture in Korea, a widow's status and position are apt to be ambiguous between her husband's home and her parent's. Therefore a new study on family culture should be made. 3) A continuous study on growing social Self Help Groups should be requested for the widows of this study to re-establish and recover from their twisted and scattered lives.

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Characterization and Classification of Potential Acid Sulfate Soils on Flood-plains (하해혼성(河海混成) 잠재특이산성토양(潛在特異酸性土壤)의 분포(分布)와 분류(分類))

  • Jung, Yeun-Tae;No, Yeong-Pal;Baeg, Cheong-Oh
    • Korean Journal of Soil Science and Fertilizer
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    • v.22 no.3
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    • pp.173-179
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    • 1989
  • Characterization and classification of the potential acid sulfate soils found on flood-plains in Yeongnam area were summarized as follows: 1. The "Potential acid sulfate soil" layer(s) were appeared in the around 2-4m substrata of soil profiles and characterized by the fine texture, high reduction and physical unripened soft mud deposits or having higher contents of organic matter with dark color. 2. The contents of total sulfur (T-S) in those soils were ranged around 0.45-0.9% and the materials exhibited a strong acidity upon the oxidation with $H_2O_2$. Although the T-S contents was low as much as 0.15%, the sulfidic materials were also acidified strongly by the oxidation with $H_2O_2$ in the condition of lower content of carbonates. As defined in Soil Taxonomy of USDA, most of the sulfidic materials contained less than 3 times carbonate ($CaCO_3$ equivalent wt. %), but there were some which abundant in shell fragments, contained more than 3 times carbonate by weight percentage and that not much acidified by the oxidation with $H_2O_2$. 3. The contents of T-S correlated negatively with the pH oxidized by $H_2O_2$ and with the fizzing time (minutes) due to addition of $H_2O_2$. 4. The potential acid sulfate soils could be defined as soil materials that had sulfidic layer(s) more than 20cm thick within 4m of the soil profile and contained more than 0.15% of T-S with less than 3 times carbonate ($CaCO_3$ equiv. %). A tentative interpretative soil classification system was proposed, i.e., "Weak potential acid sulfate (T-S, 0.15-0.5%)", "Moderate potential acid sulfate (T-S, 0.5-0.75%)", and "Strong potential acid sulfate (T-S, more than 0.75%)". Finally, it was proposed that the "Detailed soil survey with high intensity" should be carried out in the areas of agricultural engineering works such as arableland readjustment works, in advance.

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Study of Oil Palm Biomass Resources (Part 5) - Torrefaction of Pellets Made from Oil Palm Biomass - (오일팜 바이오매스의 자원화 연구 V - 오일팜 바이오매스 펠릿의 반탄화 연구 -)

  • Lee, Ji-Young;Kim, Chul-Hwan;Sung, Yong Joo;Nam, Hye-Gyeong;Park, Hyeong-Hun;Kwon, Sol;Park, Dong-Hun;Joo, Su-Yeon;Yim, Hyun-Tek;Lee, Min-Seok;Kim, Se-Bin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.48 no.2
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    • pp.34-45
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    • 2016
  • Global warming and climate change have been caused by combustion of fossil fuels. The greenhouse gases contributed to the rise of temperature between $0.6^{\circ}C$ and $0.9^{\circ}C$ over the past century. Presently, fossil fuels account for about 88% of the commercial energy sources used. In developing countries, fossil fuels are a very attractive energy source because they are available and relatively inexpensive. The environmental problems with fossil fuels have been aggravating stress from already existing factors including acid deposition, urban air pollution, and climate change. In order to control greenhouse gas emissions, particularly CO2, fossil fuels must be replaced by eco-friendly fuels such as biomass. The use of renewable energy sources is becoming increasingly necessary. The biomass resources are the most common form of renewable energy. The conversion of biomass into energy can be achieved in a number of ways. The most common form of converted biomass is pellet fuels as biofuels made from compressed organic matter or biomass. Pellets from lignocellulosic biomass has compared to conventional fuels with a relatively low bulk and energy density and a low degree of homogeneity. Thermal pretreatment technology like torrefaction is applied to improve fuel efficiency of lignocellulosic biomass, i.e., less moisture and oxygen in the product, preferrable grinding properties, storage properties, etc.. During torrefacton, lignocelluosic biomass such as palm kernell shell (PKS) and empty fruit bunch (EFB) was roasted under an oxygen-depleted enviroment at temperature between 200 and $300^{\circ}C$. Low degree of thermal treatment led to the removal of moisture and low molecular volatile matters with low O/C and H/C elemental ratios. The mechanical characteristics of torrefied biomass have also been altered to a brittle and partly hydrophobic materials. Unfortunately, it was much harder to form pellets from torrefied PKS and EFB due to thermal degradation of lignin as a natural binder during torrefaction compared to non-torrefied ones. For easy pelletization of biomass with torrefaction, pellets from PKS and EFB were manufactured before torrefaction, and thereafter they were torrefied at different temperature. Even after torrefaction of pellets from PKS and EFB, their appearance was well preserved with better fuel efficiency than non-torrefied ones. The physical properties of the torrefied pellets largely depended on the torrefaction condition such as reaction time and reaction temperature. Temperature over $250^{\circ}C$ during torrefaction gave a significant impact on the fuel properties of the pellets. In particular, torrefied EFB pellets displayed much faster development of the fuel properties than did torrefied PKS pellets. During torrefaction, extensive carbonization with the increase of fixed carbons, the behavior of thermal degradation of torrefied biomass became significantly different according to the increase of torrefaction temperature. In conclusion, pelletization of PKS and EFB before torrefaction made it much easier to proceed with torrefaction of pellets from PKS and EFB, leading to excellent eco-friendly fuels.

A Study on Fuel Quality Characteristics of F-T Diesel for Production of BTL Diesel (BTL 디젤 생산을 위한 F-T 디젤의 연료적 특성 연구)

  • Kim, Jae-Kon;Jeon, Cheol-Hwan;Yim, Eui-Soon;Jung, Choong-Sub;Lee, Sang-Bong;Lee, Yun-Je;Kang, Myung-Jin
    • Journal of the Korean Applied Science and Technology
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    • v.29 no.3
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    • pp.450-458
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    • 2012
  • In order to reduce the effects of greenhouse gas (GHG) emissions, the South Korean government has announced a special platform of technologies as part of an effort to minimize global climate change. To further this effort, the Korean government has pledged to increase low-carbon and carbon neutral resources for biofuel derived from biomass to replace fossil and to decrease levels of carbon dioxide. In general, second generation biofuel produced form woody biomass is expected to be an effective avenue for reducing fossil fuel consumption and greenhouse gas (GHG) emissions in road transport. It is important that under the new Korean initiative, pilot scale studies evolve practices to produce biomass-to-liquid (BTL) fuel. This study reports the quality characteristics of F-T(Fischer-Tropsch) diesel for production of BTL fuel. Synthetic F-Tdiesel fuel can be used in automotive diesel engines, pure or blended with automotive diesel, due to its similar physical properties to diesel. F-T diesel fuel was synthesized by Fischer-Tropsch (F-T) process with syngas($H_2$/CO), Fe basedcatalyst in low temperature condition($240^{\circ}C$). Synthetic F-T diesel with diesel compositions after distillation process is consisted of $C_{12}{\sim}C_{23+}$ mixture as a kerosine, diesel compositions of n-paraffin and iso-paraffin compounds. Synthetic F-T diesel investigated a very high cetane number, low aromatic composition and sulfur free level compared to automotive diesel. Synthetic F-T diesel also show The wear scar of synthetic F-T diesel show poor lubricity due to low content of sulfur and aromatic compounds compared to automotive diesel.