• 제목/요약/키워드: water control

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Thirteen-week Repeated Oral Dose Toxicity Study of WK-38 in Rats (랫트에서 WK-38에 대한 13주 반복경구투여 독성에 관한 연구)

  • Chang, Bo-Yoon;Kim, Yoon-Chul;Kang, Dae-Gill;Lee, Ho-Sub;Kim, Sung-Yeon
    • Journal of Food Hygiene and Safety
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    • v.23 no.2
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    • pp.169-176
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    • 2008
  • The subcronic toxicity of WK-38, a herbal preparation for the atherosclerosis, was examined in male and female Sprague-Dawley rats. WK-38 is composed of Rhei Rhizoma, Magonoliae Cortx, Moutan Cortex Radicis. Rats were treated with the test substance at a dose of 5 mg/kg, 50 mg/kg and 500 mg/kg intragastrically for 13 weeks. Control rats were treated with vehicle only. No death and abnormal clinical signs were observed throughout the administration period. Also there was no difference in net body weight gain, food and water consumption, organ weight, gross pathological findings, and urine analysis among the groups of rats treated with different doses of the WK-38. Hematological findings and biochemical examination revealed no evidence of specific toxicity related to WK-38. The results suggested that under the condition employed in this study no observation effect level (NOEL) of WK-38 would be 500 mg/kg/day.

Similitude Law on Material Non-linearity for Seismic Performance Evaluation of RC Columns (RC기둥의 내진성능평가를 위한 재료비선형 상사법칙)

  • Lee, Do-Keun;Cho, Jae-Yeol
    • Journal of the Korea Concrete Institute
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    • v.22 no.3
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    • pp.409-417
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    • 2010
  • This paper discusses a series of experiments including material improvement in order to ensure quality of grouting for the post-tensioned structure. In prestressed concrete, grouting refers to the construction procedure of filling empty space of duct enclosing with strands using cementitious material, To date, adequate quality control of the grouting has not been established in Korea because the relationship between the grouting and durability of post-tensioned structure is not well-recognized. The Korean standard does not consider the important material characteristic, wick effect, which is caused by strands in the ducts and current standard testing method unlikely quantify reasonable material segregation. As a result, the grout material, which meets the current material standards, may exhibit excessive bleeding water or shrinkage during construction. In this study, international codes and standards related to grouting were surveyed. The ratio of constituents and novel admixtures were suggested to meet equivalently with these standards. Performance of this enhanced grout was compared to common domestic grout using the international standard testing method. A series of mock-up specimens considering geometry of PC beam was constructed and grout flow pattern was observed as the grout was injected. It was observed that the grouting performance was highly influenced by material properties and filling characteristic can be varied depending on geometry of ducts.

Removal of Cu(II) with the Recycled Hydroxylapatite from Animal Bones (동물뼈로부터 재활용된 hydroxylapatite를 이용한 Cu(II) 제거)

  • Kim, Mu-Nui;Kim, Won-Gee;Lee, Seung-Mok;Yang, Jae-Kyu
    • Journal of Korean Society of Environmental Engineers
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    • v.31 no.9
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    • pp.735-742
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    • 2009
  • The bone of spinal animals has a hydroxylapatite ($Ca_{10}(PO_4)_6(OH)_2$, HAp) structure which is well known as an excellent inorganic ion exchanger for various heavy metal ions in solutions. In this study, the reusability of cow-bone, pig-bone and fish-bone as a potential material for the removal of heavy metals in solutions was evaluated from the removal of Cu(II) ion in batch tests. The surface properties of three bones, calcined at different temperatures, were measured with SEM, XRD, FT-IR analyses. From the SEM analysis, a clear development of heterogeneity as well as pores having small diameter was observed as the calcination temperature increased. The results of X-ray diffraction analysis showed well developed crystallinity on the surface of calcined bones obtained at higher temperatures, suggesting a transform of amorphous type to crystalline type. Fourier transform infrared (FT-IR) analysis showed disappearance of water molecule on the surface of HAp and organic functional groups of the HAp with increasing the calcination temperatures. Cu(II) removal in the control test was below 15%. By the way, additional 40% increase of Cu(II) removal was observed in the presence of calcined bones. For three bones, Cu(II) removal was decreased as the calcined temperature increased. Cu(II) removal was increased as the solution pH increased due to a favorable condition for the cation exchange as well as precipitation.

Experimental Studies on Antitumor Activity of Herb Drugs (I)-Effectiveness on Rat Natural Killer Cell Activity- (수종(數種)의 생약(生藥)에 대(對)한 항암효과(抗癌效果)의 실험적(實驗的) 연구(硏究)(I) -백서(白鼠)의 자연살해세포활성(自然殺害細胞活性)에 미치는 영향(影響)-)

  • Kang, Yun-Ho;Kim, Byung-Woon;Ha, Youn-Mun;Park, Jai-Kyung;Nam, Sang-Yun;Choi, Kyu-Chul;Choi, Yong-Mook
    • Korean Journal of Pharmacognosy
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    • v.18 no.2
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    • pp.118-126
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    • 1987
  • Natural Killer cells are considerd to play an important role in antitumor immune surveilance mechanism. In this study, 21 putative anticancer drugs selected from reference were assessed by evaluating the effect on rat Natural Killer cell activity (NKCA). All 21 herb drugs were extracted in boiling water, lyophilized, autoclaved, and then used for experiment. Culture supernatant of concanavalin-A (Con-A)-stimulated rat spleen cells as a source of lymphokine was also used as a control of comparison. Rat spleen cells were used as effector and NKCA was measured in 4hr $^{51}Cr-release$ assay against Yac-1 mouse lymphoma cell line. In order to determine the optimal conditions for NKCA augmentation, effector cells were treated with 3 different concentrations of each drug for 24, or 48 hrs before testing of NKCA, In optimal conditions determined from previous results, the effect of herb drugs on NKCA were assessed in 3 to 5experiments. NKCA was significantly enhanced by treatment with 4 herb drugs(Ponciri Fructus, Houttuyniae Herba, Aurantii Pericarpium, Nepetae Herba). Culture supernatant of Con-A-stimulated spleen cells also augmented the rat NKCA more significantly. The results show that 4 of the herb medicines supposed to display anticancer effect may have activity as a biological response modifier through augmentation of NKCA.

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Mechanisms of Salt Tolerance in Crop Plants I. Physiological Responses of Barley, Rye and Italian Ryegrass Seed Germination to NaCl Concentrations (작물의 내염성 기작연구 I. 염분농도에 따른 보리, 호밀, 이탈리안 라이그래스 종자의 발아생리반응)

  • 김충수;조진웅;이석영
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.38 no.4
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    • pp.371-376
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    • 1993
  • This experiment was conducted to elucidate the salt tolerance mechanism of crop plants. Plants used in this experiment were rye, barley, Italian ryegrass. Seeds were treated at saline condition and the saline conditions were controlled by NaCl. The results were summerized as follows. In rye, germination ratio and speed were above 90% and 80% at NaCl concentrations below 0.5% but germination ratio was seriously decreased at NaCl concentration above 0.6%. In barley germination ratio was not less than 80% at NaCl concentration below 0.8%. In italian rye grass germination ratio was decreased gradually by increasing NaCl concentration but germination speed was seriously decreased at NaCl concentration above 0.6% as not more than 7.5%. Water absorption rate was low in barley than rye and it was decreased by increasing NaCl concentration and duration of absorption. In barley, carbohydrate content was decreased slightly in response to increased NaCl concentration and content of reducing sugar was independent of NaCl concentration. In rye, reducing sugar content was increased until 0.3% of NaCl and increased seriously after 20 hours. $\beta-Amylase activity was high at control and 0.6% lot of NaCl, but it was not general tendency.

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Principles and Applications of Multi-Level H2O/CO2 Profile Measurement System (다중 수증기/이산화탄소 프로파일 관측 시스템의 원리와 활용)

  • Yoo, Jae-Ill;Lee, Dong-Ho;Hong, Jin-Kyu;Kim, Joon
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.11 no.1
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    • pp.27-38
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    • 2009
  • The multi-level profile system is designed to measure the vertical profile of $H_2O$ and $CO_2$ concentrations in the surface layer to estimate the storage effects within the plant canopy. It is suitable for long-term experiments and can be used also in advection studies for estimating the spatial variability and vertical gradients in concentration. It enables the user to calculate vertical fluxes of water vapor, $CO_2$ and other trace gases using the surface layer similarity theory and to infer their sources or sinks. The profile system described in this report includes the following components: sampling system, calibration and flow control system, closed path infrared gas analyzer(IRGA), vacuum pump and a datalogger. The sampling system draws air from 8 inlets into the IRGA in a sequence, so that for 80 seconds air from all levels is measured. The calibration system, controlled by the datalogger, compensates for any deviations in the calibration of the IRGA by using gas sources with known concentrations. The datalogger switches the corresponding valves, measures the linearized voltages from the IRGA, calculates the concentrations for each monitoring level, performs statistical analysis and stores the final data. All critical components are mounted in an environmental enclosure and can operate with little maintenance over long periods of time. This report, as a practical manual, is designed to provide helpful information for those who are interested in using profile system to measure evapotranspiration and net ecosystem exchanges in complex terrain.

Effects and Future Prospect of the Cooperative Culture of Low-land Rice in Korea (우리나라 수도지반재배의 효과와 전망)

  • Min-Shin Cho
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.7 no.1
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    • pp.85-92
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    • 1969
  • The goal for the improvement of rice culture in our country is to increase the rice yield per unit area, and that thoroughly, to equalize the rice yield per unit are highly by adaptation of high technique, while on the side of the efficiency, to increase the productivity of the labour through the cooperative work. And then, the theory for execution of the cooperative rice culture which is the productive system embodying the goal above and the expected effects as well as the future prospect for the development of the cooperative rice culture must be studied and defined. The results studied up to now are summarized as follows: 1. The cooperative rice culture is one of the most effective ways to execute highly efficient farm management and to supply the technical details on the cultivation for equalized high yield per unit area in the rice cultivating districts. 2. For the most effective accomplishment of the cooperative rice culture, the water control, and soil and variety of rice must be investigated in advance an then the basic technical details for the rice culture must be defined. 3. The rice cultivation calender is drawn up with the main technical details of rice culture by the mutual agreement of all farmers belong to the cooperative farm. All technical details for the rice cultivation in the cooperative farm are standardized by the rice cultivation calendar and the main technical operations should be worked together and the other operations executed individually. 4. The technique for rice cultivation, which was difficult to be introduced in the individual farm management, could be introduced easily to the cooperative rice culture, and the rice yield of the cooperative farm was increased 23.3% compared to that of common farm in 1968. 5. At present, the type of the cooperative rice culture is a primary type of the agreement for farm management, rarely including the associated operation type and the contracted operation type for a part of operation, However, for stabilized high yield through the mechanization of the cultivation system, the cooperative farm must be developed for a course promoting the associated operation type including the technique trust type and the contracted operation type according to the condition of location.

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Effect of Naturally Occurring Antioxidants on the Oxidative Stability of Fish Oil (천연 산화방지제가 어유의 산화안정성에 미치는 영향)

  • Han, Dae-Seok;Yi, Ock-Sook;Shin, Hyun-Kyung
    • Korean Journal of Food Science and Technology
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    • v.23 no.4
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    • pp.433-436
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    • 1991
  • Natural compounds which could improve the oxidative stability of fish oil was screened from spices, herbs and naturally occurring antioxidants. Induction period of fish oil determined from oxidation curve by Rancimat ($80^{\circ}C$) was hardly affected with the addition of water-soluble and lipid-soluble fractions of garlic, leek, sesame leave and orange peel, and of organic acids such as citric acid, EDTA and selenium. Caffeic acid, catechin, quercetin and gallic acid laurylester, however, could extend the induction periods by $2.2{\sim}3.8$ times with the addition level of 0.1%(w/w). Rosemary extract and sesamol have a marked effect in retarding oxidation of fish oil. For example, induction periods of the oil samples stabilized with 0.1 rosemary extract and 0.1 sesamol were 16.4 hr and 11.6 hr, respectively, as compared to 4.0 hr of a control. When rosemary extract was used in combination with ascorbic acid (0.02%) or 8-tocopherol (0.2%), induction period could be extended to ca. 28 hr due to the synergism.

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Survey of the level of Microbial Contamination in Fish Farms on the Jeju-Island (제주도 어류양식장에 대한 미생물학적 오염도 조사)

  • Moon, Young-Gun;Ha, Jin-Hwan;Kang, Chang-Hee;Song, Chung-Bok;Oh, Myung-Cheol;Heo, Moon-Soo
    • Journal of Food Hygiene and Safety
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    • v.22 no.3
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    • pp.179-191
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    • 2007
  • The purpose of this study was to monitor and compare the contamination levels of heterotrophic bacteria and pathogenic bacteria (total coliforms, Escherichia coli O157:H7, Salmonella spp., Vibrio parachaemolyticus, Staphylococcus aureus and Bacillus cereus). The samples collected at fish farms located in the Jeju-island were investigated from March to August in 2006. The contamination levels of S. aureus, B. cereus and Salmonella spp. ranged $0-3.3{\times}10^2 CFU/ml,\;0-2.2{\times}10^2 CFU/ml\;and\;0-5.1{\times}10^1CFU/ml$, respectively, and 85% of moist pellet feeds were contaminated with S. aureus, B. cereus and total coliforms. But total coliforms and E. coli O157:H7 were not detected in oliver flounder (Paralichthys olivaceus). For the production of safe oliver flounder (Paralichthys olivaceus), education of sanitation for employees, control of fish feed, and continuous monitoring for microorganism will be required.

A Study for the Development of BoreanNursing TheoT : A Humanistic Approach based on Shinhyung,- Naekyungpyun in Dongeuibogam (한국 간호이론 정립을 위한 연구 I-동의보감을 중심으로 본 인간관-)

  • 신경림
    • Journal of Korean Academy of Nursing
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    • v.27 no.1
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    • pp.141-155
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    • 1997
  • The universe has its order of yang and yin : all creation are continuously generated, grow and die, which is the results of the harmonious operation by yang and yin. Among all creation, the human is one of the samjae(three bases of the world, which are heaved earth, and man) and he is from the combined sukhi(a superior khi) of yang and yin. And human life itself is basically a condensed jonghyul (life blood) and at the same time it is only a transient joining of sadae(the four elements of earth, air, fire and water). Yang and yin, the two axes of the world, therefore. are the most crucial and fundamental concept to explain the generation and extinction of alt creation, to understand people in time and space. to find out the reality of human life as an organism, and, at last, to observe the state of human health. If so, what is the most essential idea in yang and yin\ulcorner It is taegeuk(chungkhi) or tao(of one yang and one yin). If the property of heaven and earth is kongon, taegeuk is a khi and tao a principle. And it can be said that a human body is merely a union of hyung and khi, that human life is an essence of sambo, jeongkhishin, that human health is a harmoninzed coordination of yang and yin because it is from the combined sukhi of yang and yin. Hyung. a vessel for sambo, jeongkhishin, is at the bottom and shin is on the top : the personality and the disposition of individuals differ according to their working. Thus. on the basis of the above discussion. the following can be offered as some suggestions for Korean Nursing Theory. Though human beings are part of Nature, they are the most eminent microcosm among all creation. So, as a subjet for nursing, a person should be understood with khijok kyoryu rather than with logical thinking, then mutual trust between the patient and the nurse can be established. The health of a person depends on the harmony of yang and yin. To be healthy, a person should consider harmonization with Nature(including his surroundings) as well as a balanced human relationships in society. Moreover, it is crucial for each person to obtain hoshim as a method of mind control rather than to only treat the symptoms of disease.

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