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An Analysis of Students' Difficulty on Science Stories in Elementary School Science Textbooks - Focusing on 6th Grade Science (초등학교 과학교과서에 기술된 과학이야기에 대한 학생들의 어려움 분석 - 6학년 과학을 중심으로 -)

  • Lim, Younghyun;Shin, Youngjoon
    • Journal of Science Education
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    • v.38 no.3
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    • pp.525-542
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    • 2014
  • This study was performed to look into the difficulty of students in understanding science stories in 6th grade science textbooks and to analyze those factors. To do this, 6th grader (N=65) were selected from J Elementary School located in Gyeonggi-do Siheung-si as study subjects. 26 science stories in 6th grade science textbooks were classified by field and context (complement of knowledge, science history of scientists, science in life, cutting-edge science technology, environment issues) in which the characteristics were investigated and analyzed. Also, a survey about the difficulty in understanding science stories(26 items) was conducted(65 students) and a semi-structured interview was conducted for students to clarify the meaning of collected data from surveys(4 students). As result of analyzing surveys on science story context in science textbooks and interviews, 4 fields of 'energy,' 'matter,' 'life,' and 'earth' were evenly mentioned. Science in life and complement of science knowledge were mentions most for context and this had relation with the characteristic of science textbooks to provide many opportunities to apply learned knowledge in actual social issues. Reactions of students on science stories were mostly positive that they help studying science, but there was also difficulty in well understanding science stories. Difficulty of understanding context, problems of context suggesting methods, difficulty of science terminology, lack of interest, and etc. were analyzed as factors. Specific causes were mentioned to be description type class, unimportant context, lack of explanation on suggested context, problem of pictures by students.

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Studies on the Physico-chemical Properties and Characterization of Soil Organic Matter in Jeju Volcanic Ash Soil (제주도(濟州道) 화산회토양(火山灰土壌)의 이화학적(理化学的) 특성(特性) 및 유기물(有機物) 성상(性状)에 관(関)한 연구(硏究))

  • Lee, Sang-Kyu;Cha, Kyu-Seuk;Kim, In-Tak
    • Korean Journal of Soil Science and Fertilizer
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    • v.16 no.1
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    • pp.20-27
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    • 1983
  • A series of laboratory experiment was conducted to find out the chemical composition, characterization of humic substances by physical and chemical methods and reaction of Na-pyrophosphate, $Ca(OH)_2$ and rice straw with albumin on the degradation of soil organic matter in the volcanic ask soils of the Jeju Island. Results obtained were summarized as follows: 1. The contents of organic matter, available silicon, active iron and aluminum concentration in volcanic ash the soils were remarkably higher but available phosphorous was comparatively lower than the mineral soils. In volcanic ash soil, the contents of potassium, calcium and magnessium were higher in upland soil than that of forest soil. The ratios of active $Al^{{+}{+}{+}}/Fe^{{+}{+}}$, C/P and $K/Ca^+$ Mg were apparently high in volcanic ash soils while that of $SiO_2$/O.M. was high in mineral soil. 2. The carbon/nitrogen ratio in humin, humic acid content in organic matter, and carbon contents of humin in total carbon of soil organic matter were apparently higher in the volcanic ash soils than in the mineral soils, The total nitrogen and fractions of acid or alkali soluble nitrogen were remarkably high in volcanic ash soils while mineralizable nitrogen ($NH_4$-N and $NO_3$) contents were high in mineral soils. 3. The values of K600, RF and log K were also higher in volcanic ash soils than those in mineral soils, and the absorbance in the visible range were high and color was dark in the soil of which humification was progressed Extracted humic acid from volcanic ash soil was less reactive to the oxidizing chemical reagent and was persistance to the acid or alkali hydrolysises. 4. The major oxygen-containing functional groups in humic substances of volcanic ash soils were phenolic-OH alcoholic-OH and carboxyl groups while those in mineral soil were methoxyl and carbonyl groups. 5. Absorption spectra of alkaline solution of humic acid ranged from 200 nm to maxima 500 nm. Visible spectra peaks of from humic substances in the visible region were recognized at 350, 420, 450 and 480 nm. Only one single absorbance peak was observed in the visible region at 362 nm for Heugag series and two absorbance Peak were also at 360 nm and 390 nm for Yeungrag series. 6. Evolution of carbon as $Co_2$ was increased with addition of Na-pyrophosphate in Namweon and Heugag series, and "priming effects" took place on the soil organic matter decomposition by addition of rice straw with albumin in Ido series.

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Processing and Property of Olive Flounder Paralichthys olivaceus Steak (넙치(Paralichthys olivaceus)스테이크제품의 제조 및 품질특성)

  • Yoon, Moon-Joo;Kwon, Soon-Jae;Lee, Jae-Dong;Park, Si-Young;Kong, Cheong-Sik;Joo, Jong-Chan;Kim, Jeong-Gyun
    • Journal of Fisheries and Marine Sciences Education
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    • v.27 no.1
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    • pp.98-107
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    • 2015
  • Olive flounder contains rich amount of lysine which is required for children's growth. Moreover, it is good foodstuffs for elderly, convalescent and diabetics because of low lipid content and high digestibility. This study was investigated for the purpose of obtaining basic data which can be applied to the processing of olive flounder steak. Olive flounder 100 g were chopped, mixed with vegetable (onion 20%, celery 10%, carrot 15%, garlic 1% of chopped olive flounder meat) and ingredient (bread crumbs 20 g, onion 15 g, celery 10 g, egg 1 ea, tarragon 1/2 t, blanc sauce 20 g, fresh cream 20 mL, salt and pepper pinch). Mixed dough was molded into steak shape ($12{\times}7cm$) and was processed by two types of products, Steak-1 {Roasting for 2 minutes in a frying pan wrapped with olive oil and then vacuum packaging in polyethylene film ($20{\times}30{\times}0.05mm$), and then storage at $-20^{\circ}C$ for 7 days, next thawed and warmed by microwave for 2 minutes} and Steak-2 {vacuum-packaging in polyethylene film ($20{\times}30{\times}0.05mm$), and then storage at $-20^{\circ}C$ for 7 days, after thawed, roasted during 2 minutes in a frying pan wrapped with olive oil}. The factors such as pH, TBA value, amino-N, free amino acid, chemical composition, color value (L, a, b), texture profile, sensory evaluation and viable bacterial count of the olive flounder steak (Steak-1, Steak-2) were measured. From the result of sensory evaluation, Steak-2 showed a bit more high scores than Steak-1 but it was difficult to distinguish significant difference (color, odor, taste, texture and acceptance) between Steak-1 and Steak-2 products.

Characterization of Grain Amino Acid Composition and Proteome Profile of a High-lysine Barley Mutant Line M98 (고-Lysine 보리 돌연변이 계통 M98 종실의 아미노산 조성 및 Proteome Profile 특성)

  • Kim, Dea-Wook;Kim, Hong-Sik;Park, Hyoung-Ho;Hwang, Jong-Jin;Kim, Sun-Lim;Lee, Jae-Eun;Jung, Gun-Ho;Hwang, Tae-Young;Kim, Jung-Tae;Kim, Si-Ju;Rakwal, Randeep;Kwon, Young-Up
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.57 no.2
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    • pp.171-181
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    • 2012
  • Lysine is the first limiting essential amino acid in cereals for humans and monogastric animals, although its content is generally low. A chemically induced high-lysine barley mutant, M98, has an agronomically undesirable shrunken endosperm trait. In order to obtain detailed insight into the atypical traits of M98 grains, we characterized amino acid composition and protein profiles of M98 and its parent cultivar Chalssalbori. Among a total of 16 amino acids, the percentage of each of the 7 amino acids, including lysine, was 1.2~1.8 times higher in M98, comparing to Chalssalbori. The percentage of proline and its precursor, glutamic acid, in M98 was about the half of that of the amino acids in Chalssalbori, but arginine synthesized from glutamic acid was 1.8 times higher in M98, compared that in the parent cultivar. Theses results indicated that the mutation in M98 grains might alter the proportion of amino acids linked to each other in a biosynthetic pathway. A comparison of grain proteome profiles between Chalssalbori and M98 revealed 70 differentially expressed protein spots, where 45 protein spots were up-regulated and 25 protein spots down-regulated in M98 compared to those in Chalssalbori. Of these changed protein spots, 53 were identified using nano-electrospray ionization liquid chromatography mass spectrometry. Most of these identified proteins were involved in various biological processes. In particular, 28 protein spots such as ${\beta}$-amylase, serpins and B3-hordein were identified as proteins associated with the atypical traits of M98. It was thought that a genetic study on the unique protein profile of M98 would be needed to develop an agronomically feasible barley cultivar with high-lysine trait.

Study on the Consequence Effect Analysis & Process Hazard Review at Gas Release from Hydrogen Fluoride Storage Tank (최근 불산 저장탱크에서의 가스 누출시 공정위험 및 결과영향 분석)

  • Ko, JaeSun
    • Journal of the Society of Disaster Information
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    • v.9 no.4
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    • pp.449-461
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    • 2013
  • As the hydrofluoric acid leak in Gumi-si, Gyeongsangbuk-do or hydrochloric acid leak in Ulsan, Gyeongsangnam-do demonstrated, chemical related accidents are mostly caused by large amounts of volatile toxic substances leaking due to the damages of storage tank or pipe lines of transporter. Safety assessment is the most important concern because such toxic material accidents cause human and material damages to the environment and atmosphere of the surrounding area. Therefore, in this study, a hydrofluoric acid leaked from a storage tank was selected as the study example to simulate the leaked substance diffusing into the atmosphere and result analysis was performed through the numerical Analysis and diffusion simulation of ALOHA(Areal Location of Hazardous Atmospheres). the results of a qualitative evaluation of HAZOP (Hazard Operability)was looked at to find that the flange leak, operation delay due to leakage of the valve and the hose, and toxic gas leak were danger factors. Possibility of fire from temperature, pressure and corrosion, nitrogen supply overpressure and toxic leak from internal corrosion of tank or pipe joints were also found to be high. ALOHA resulting effects were a little different depending on the input data of Dense Gas Model, however, the wind direction and speed, rather than atmospheric stability, played bigger role. Higher wind speed affected the diffusion of contaminant. In term of the diffusion concentration, both liquid and gas leaks resulted in almost the same $LC_{50}$ and ALOHA AEGL-3(Acute Exposure Guidline Level) values. Each scenarios showed almost identical results in ALOHA model. Therefore, a buffer distance of toxic gas can be determined by comparing the numerical analysis and the diffusion concentration to the IDLH(Immediately Dangerous to Life and Health). Such study will help perform the risk assessment of toxic leak more efficiently and be utilized in establishing community emergency response system properly.

Evaluation of Drainage Improvement Effect Using Geostatistical Analysis in Poorly Drained Sloping Paddy Soil (경사지 배수불량 논에서 배수개선 효과의 지구통계적 기법을 이용한 평가)

  • Jung, Ki-Yuol;Yun, Eul-Soo;Park, Ki-Do;Park, Chang-Young
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.6
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    • pp.804-811
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    • 2010
  • The lower portion of sloping paddy fields normally contains excessive moisture and the higher water table caused by the inflow of ground water from the upper part of the field resulting in non-uniform water content distribution. Four drainage methods namely Open Ditch, Vinyl Barrier, Pipe Drainage and Tube Bundle for multiple land use were installed within 1-m position from the lower edge of the upper embankment of sloping alluvial paddy fields. Knowledge of the spatial variability of soil water properties is of primary importance for management of agricultural lands. This study was conducted to evaluate the effect of drainage in the soil on spatial variability of soil water content using the geostatistical analysis. The soil water content was collected by a TDR (Time Domain Reflectometry) sensor after the installation of subsurface drainage on regular square grid of 80 m at 20 m paddy field located at Oesan-ri, Buk-myeon, Changwon-si in alluvial slopping paddy fields ($35^{\circ}22^{\prime}$ N, $128^{\circ}35^{\prime}$). In order to obtain the most accurate field information, the sampling grid was divided 3 m by 3 m unit mesh by four drainage types. The results showed that spatial variance of soil water content by subsurface drainage was reduced, though yield of soybean showed the same trends. Value of "sill" of soil water content with semivariogram was 9.7 in Pipe Drainage, 86.2 in Open Ditch, and 66.8 in Vinyl Barrier and 15.7 in Tube Bundle.

A Documentational Study on the Development of Chi-Kung-Hak (기공학(氣功學) 발달(發達)에 관한 문헌적(文獻的) 연구(硏究))

  • Kim Woo-Ho;Hong Won-Sik
    • Journal of Korean Medical Ki-Gong Academy
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    • v.1 no.1
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    • pp.13-59
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    • 1996
  • Dep. of Classics &Medical History, College of Oriental Medicint, Kyung Hee University Today, many people are more interested Today, many people are more interested in preventing the disease than curing it. Chi-Kung(氣功) is the way of Life-Cultivation(養生法) peculiar to the orient, it is reported in china that Chi-Kung has an excellent curative value not only in curing the disease but also in preventing it. But the full-scale study of Chi-Kung is not be made up to now in Korea, so I studied the developmental history of chinese Chi-Kung through the oriental medical books. From this study, I reached the following conclusions; 1. Chi-Kung is naturally derived from the self-preservation instinct to adapt oneself to circumstances of the nature, but in the investigation from the documentational records, it is originated in the treatment method of the Sam-Huang-O-Jae(三皇五帝) period to cure the abnormal circulation of the vital force and blood caused by damp(濕). 2. As the principle and the method of the Life-Cultivation of the Chun-Chu-Jeon-Kook(春秋戰國) period were recorded in Huang-Jae-Nai-Gyung(黃帝內經) detailly and the remedy examples by ancient Chi-Kung such as Tao-Yin(導引), Haeng-Chi(行氣) were presented, we considered that theoretical basis of the development of Life-cultivation and Chi-Kung study was furnished in that period. 3. A famous doctor, Hwa-Ta(華引) lived in Han dynasty, researched the theory and practice of Tao-Yin transmitted from the former generations, as that result, he formed a kind of medical, gymnastics what is called O-Keum-Hi(五禽?). It is considered that 'O-Keum-Hi' is a Tao-Yin method developed more practically and systemetically than the Tao-Yin appeared in the 'Jang-Ja'(莊子) or 'Hoy-Nam-Ja'(淮南子). 4. In Wui-Jin-Nambook-Jo(魏曺南北朝) periods, the contents of Chi-Kung were more abundant under the influence of Buddhism(佛敎) and Taoism(道敎). Galhong(葛洪), the author of 'Po-Bak-Ja'(抱朴子) arranged the ancient Chi-Kung method systematically first of all, Tao-Goeng-Gyung, the author of 'Yang-Seong-Yeun-Myung-Rok'(養性延命錄) recorded the 'Yook-Ja-Geul'(六字訣) first time. 5. There is a new development of Chi-Kung therapy in Soo-Tang-Odae(隋唐五代) periods, especially So-Won-Bang(巢元方), the author of 'Jey-Bang-Won-Hwu-Ron' collected almost all of the Chi-Kung method, for curing the disease formed before Soo(隋) period. From that fact, we supposed that Chi-Kung was utilized more widely in curing the disease. 6. 'So-Ju-Cheon-Hwa-Hu-Peob'(小周天火候法) was adopted as the best orthodox approach under the influence of Nae-Tan-Taoist(道敎內丹學波) in Song-Keum-Won(宋金元) periods, especially in the song dynasty, 'Pal-Dan-Geum'(八段錦) was appearde and assignment of six-Chi(六氣) for bowel and viscera in the 'Yook-Ja-Geul'(六字訣) was decided firmly, that is to say Lung-Si(肺-?), Heart-Kha(心-呵), Spleen-Hoa(脾-呼), liver-Hoe(肝-噓), Kidney-chui(賢-吹), Three-Burner-shi(三焦-?). 7. In Myung-Cheong(明淸) periods, The general practitioner applied the principle of 'Byun-Jeng-Ron-Chi(辨證論治) to the Chi-Kung field, and after Myung dynasty the style of doing 'Yook-Ja-Gyel'(六字訣) was developed to the moving style. 8. Today, in china, the study on the Chi-Kyung is being progressed constantly under the positive assistance of government, Chi-Kung-Hak(氣功學) has taking its place as a branch of study step by step. It is considered that the establishment of Chi-Kung-Hak Classroom(氣功學敎室) and Medical Chi-Kung Center(氣功療法室) for special and systematic research are needed, at the same time the settlement of institutional system for training the Chi-Kung technician(氣功師) is also needed.

A Study on Dementia Alzheimer's type published to chinese magazine (중의잡지(中醫雜誌)에 보고(報告)된 Alzheimer형(型) 치매에 대(對)한 고찰(考察))

  • Chae, Jong-gul;Lee, Sang-ryong
    • Journal of Haehwa Medicine
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    • v.10 no.1
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    • pp.453-469
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    • 2001
  • This study attempted to analyze the contents of the research papers concerning the diagnosis and treatment of Alzheimer-type dementia presented in the magazine of Chinese Medicine published in China over the period between 1998 and 2000. As a result, the following conclusion was drawn: 1. The Chinese medical category of Alzheimer-type dementia includes amnesia, dementia, stupidity, depression symptom complex, insanity and the like and uses the as the criterion for diagnosis and treatment effect evaluation. 2. The clinical symptoms of Alzheimer-type dementia include lowered intelligence, deterioration of memory, understanding and judgemental power, retardation of the reaction, emotional changes, character changes, behavioral changes and the like and are divided into mild, medium and serious according to the degree of symptom. 3. From the perspective of Bon-Heo-Pyo-Shil(state of deficient vital essence and excessive pestilential vapor), the pattern of Byun-Sung(identification) is divided into deficiency symptom complex, excessive symptom complex and indiscernible fullness and emptiness. The deficiency symptom complex includes deficiency of the liver and kidney, deficiency of essence of the kidney, deficiency of the reservoir of marrow and the like. The excessive symptom complex includes internally blocked stagnant blood, blocking of the passageway due to turbid phlegm, blood stasis due to stagnation of chi, and the like. The indiscernible fullness and emptiness symptom complex includes the deficiency of essence of kidney, blocking of the passageway due to stagnant phlegm, blood stasis due to the deficiency of kidney, blood stasis due to the deficiency of heart and the like. 4. The therapeutics and' prescription of Alzheimer-type dementia include the following: Bo-Shin-Ik-Su-Tang for tonifying the kidney, replenishing the marrow and plugging the essence; Ki-Guk-Ji-Hwang-Hwan-Ga-mi for reinforcing the vital essence of the liver and kidney; Kwi-Bi-Tang-Hap-Yang-Shim-Tang for invigorating the functioning of the spleen and nourishing the heart; Hyel-Bu-Chuk-Eo-Tang-Ga-Mi for activating the blood and resolving the stagnancy of the blood; Bo-Yang-Hwan-Oh-Tang for replenishing chi, activating the blood and resolving the stagnancy of the blood; Beoh-Kwang-Mong-Sung-Tang for invigorating the functioning of the spleen, replenishing the kidney, resolving the phlegm and enlivening the brain; n-Dam-Tang-Ga-Mi for invigorating the functioning of the spleen, replenishing chi, and removing the phlegm and unclogging the passageway); Se-Shim-Tang-Ga-Mi for removing the stagnancy of the liver and resolving the phlegm; and the like. 5. The research papers on, the medication cases of Alzheimer-type dementia understand the pathology of Alzheimer-type dementia from a consistent perspective. They view the pathology of Alzheimer-type dementia as the disease of Bon-Heo-Pyo-Shil(state of deficient vital essence and excessive pestilential vapor) with the combination of the deficiency of essence of the kidney, the deficiency of the brain marrow, blood stasis and blocked phlegm and the like and recommend the prescription of using Bo and Sa simultaneously for treating Alzheimer-type dementia. 6. The research papers on the medication cases of Alzheimer-type dementia reported that the use of creative prescriptions such as Si-Sam-Hang-Ji-Tang, Ji-Yung-Tang, Ka-Mi-Yunh-Ji-Hwan, Ja-Sin-Hwal-Hyel-Tang, Kal-Chang-Ik-Ji-Tang, Ho-Su-Bok-Ji-Tang, Kun-Noe-Ok-Ji-Hap-Je and the like led to the average high efficacy of 85.5%.

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Behaviors of Arsenic in Paddy Soils and Effects of Absorbed Arsenic on Physiological and Ecological Characteristics of Rice Plant lll. Effect of Water Management on As Uptake and the Growth of Rice Plant at As Added Soil (토양중(土壤中) 비소(砒素)의 행동(行動)과 수도(水稻)의 비소흡수(砒素吸收)에 의(依)한 피해생리(被害生理) 생태(生態)에 관(關)한 연구(硏究);Ⅲ.물관리(管理)가 수도의 비소흡수(砒素吸收) 및 생육(生育)에 미치는 영향(影響))

  • Lee, Min-Hyo;Lim, Soo-Kill-H
    • Korean Journal of Environmental Agriculture
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    • v.6 no.1
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    • pp.1-6
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    • 1987
  • A pot experiment was conducted to find out the effect of water management on the growth and uptake of arsenic and inorganic nutrients of rice plant at As added soil. The arsenic were added to soil at the levels of As 0, 10, 50, 100 and 150 ppm, respectively. Water management was done with two ways: intermittent irrigation from ten days after transplanting, and continuous submersion until harvest. Higher soil As levels increased As content in plant but reduced growth rate. Aresenic content in plant was considerably reduced with intermittent irrigation compared to continuous submersion. Rice growth showed also same trend. With increasing As levels in soil, N content in plant was increased but P, K, Ca, Mg, $SiO_2$, Fe and Mn content in plant were tend to be decreased. These inorganic nutrients in plant were also much absorbed in continuous submersion compared to intermittent irrigation. Soil pH was slightly increased with increasing As levels in soil while soil Eh has no relationship with soil As levels. On the other hand, soil pH was higher in the treatment of continuous submersion than that of intermittent irrigation but soil Eh showed reverse trend. With increasing As levels in soil, water soluble-As and Ca-As fractions in soil tend to be increased with continuous submersion, but these fractions has no tendency with intermittant irrigation.

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