• Journal of The Korean Association For Science Education
• /
• v.20 no.3
• /
• pp.364-370
• /
• 2000

In this study, 10th-grade students' conceptions concerning acid rain, ozone layer, and greenhouse effect were investigated. A conception test that asked to explain about the three concepts and the relationships among them was administered to 137 students. Analysis of their responses indicated that students had lack of understanding about the definition of acid rain, the difference between greenhouse effect and global warming, and how to prevent the increase in greenhouse effect. They also confused ozone layer with greenhouse effect. Many students thought that there were causal relationships among the increase of acid rain, the destruction of ozone layer, and the increase in greenhouse effect.

• The Korean Journal of Ecology
• /
• v.28 no.3
• /
• pp.169-180
• /
• 2005

Nitrogen dioxide concentration was being grown ca. 8% per year although sulphur dioxide concentration was being reduced ca. 10% per year in Seoul from 1996 to 2003. The rainwater was heavily acidic with pH 4.19 to 4.68 in Seoul during 1980 to 1991. Acidity score on the basis of the total anion concentration of rainwater follows the higher in sequence with Seoul(Kwanaksan)(341.5 ${\mu}equiv{\cdot}L^{-1}$), Gwangneung(199.2 ${\mu}equiv{\cdot}L^{-1}$) and whole Korea mean(10.3 ${\mu}equiv{\cdot}L^{-1}$). Rainwaters from 38 sampling sites of 16 countries in the world, on the basis of the acidity score, are classified and designated as five acid rain grades(ARG): the least score is founded in Tana Rata(16.2 ${\mu}equiv{\cdot}L^{-1}$), Malaysia where has the best rain but the greatest founded in Chongquing(541.1 ${\mu}equiv{\cdot}L^{-1}$), China where has the worst rain in the world. Even though acidic deposition decrease with time in the world generally, it is expected to increase in Asia, Africa and Mid-South America.

• Asian Journal of Atmospheric Environment
• /
• v.2 no.2
• /
• pp.102-108
• /
• 2008

In China, energy and environmental problems are becoming serious owing to rapid economic development. Coal is the most problematic energy source because it causes indoor and outdoor air pollution, acid rain, and global warming. One type of clean coal technology that has been developed is the coal-biomass briquette (or bio-briquette, BB) technique. BBs, which are produced from pulverized coal, biomass (typically, agricultural waste), and a sulfur fixation agent (slaked lime, $Ca(OH)_2$) under high pressure without any binder, have a high sulfur-fixation effect. In addition, BB combustion ash, that is, the waste material, can be used as a neutralization agent for acidic soil because of its high alkalinity, which originates from the added slaked lime. In this study, we evaluated the suitability of alternative biomass sources, namely, aquatic plants, as a BB constituent from the perspective of their use as a source of energy. We selected three types of aquatic plants for use in BB preparation and compared the fuel, handling, and environmental characteristics of the new BBs with those of conventional BBs. Our results showed that air-dried aquatic plants had a higher calorific value, which was in proportion to their carbon content, than agricultural waste biomass; the compressive strength of the new BBs, which depends on the lignin content of the biomass, was high enough to bear long-range intracontinental transport in China; and the new BBs had the same emission control capacity as the conventional BBs.

• Journal of The Korean Association For Science Education
• /
• v.19 no.4
• /
• pp.585-594
• /
• 1999

The purpose of this study is to examine the concept of Greenhouse Effect as understood by middle school high school university students using a closed-form questionnaire. Based on results of the questionnaire which was administered to 619, the extent to which alternative concepts were held was quantified and compared the difference of various group based on grade level. gender, text and major. Also, subjects were divided into two groups, one is middle school students and the other is high school university students and common themes within conceptual framework of each group were identified by factor analysis. The result showed that students confused Greenhouse Effect with ozone layer depletion in stratosphere and linked familiar contamination around everyday life. acid rain. radioactive contamination, nuclear arsenal to Greenhouse Effect. These trends were more appreciable in female than male, biology major than any other major and text did not make any significant difference. In addition, the result of factor analysis showed that two groups linked familiar contamination around everyday life to Greenhouse Effect and high school university students understand the consequences of an increase in the Greenhouse Effect more systematically than middle school student, perceived the relation between the origin of an increase in the Greenhouse Effect and human activity but confused Greenhouse Effect with ozone layer depletion in stratosphere.

• Resources Recycling
• /
• v.5 no.2
• /
• pp.45-51
• /
• 1996

Domestic coal contains approximnlely 03 to 7 percentage of sulfur. When the suliur in coal is burned, exhaust gas , nay be thc causc of air pollution problcms as well as acid rain. Thc government dccideil lo strengthen the environmcnlal protection policy a1 the 270 ppm of SO, for the coal-Ered plants and to stari in Ian. 1, 1999. This study was carried out lo rcmove the stlfur and mineral mancrs in the samplw using wet msg~xiic separatol ant1 oil agglomeration apparatus. The rcsults for the wet magnetic separalion showed that the total sulfur removal from Kangnung coal sample was 60.8% with 82.6% combustible recovery. For the results of oil agglomeration testa, combustible recavety, ash nod sulfur rcmovcl horn Maro coal sample were 98.0, 70.9 and 95.7 percent, respectively.

• Journal of The Korean Association For Science Education
• /
• v.22 no.2
• /
• pp.378-386
• /
• 2002

In this study, the students' responses on the chemistry items of in the general science of College Scholastics Ability Test (CSAT) implemented for the past 3 years since 1999 were investigated. The number of items by content and inquiry process, the average percent correct by content and inquiry process, the distribution of items by the level of percent correct, and the items with high and/or low percent correct were analysed. There were the fewest items in 'environment' area, especially in 'ozon layer', no test item had been made. The most difficult content area was 'acid rain' in 'environment'. By inquiry process, the most number of items belonged to 'analyzing & interpreting data', and 'identifying problems & formulating hypothesis' was the most difficult process. No test item came under the level of 'very difficult', and many items under the 'easy' or 'very easy' level. Students were generally poor at solving test items demanding several concepts, and very good at simply requiring basic concept treated in lower grade. Educational implications are discussed.

• Journal of The Korean Association For Science Education
• /
• v.26 no.2
• /
• pp.200-211
• /
• 2006

The purpose of this study was to analyze Korean middle school student achievement in environmental science based on the TIMSS 2003 (Trends in International Mathematics and Science Study), a student comparison of 46 participating nations. Korea ranked the fourth with a mean score of 554 in environmental science. However, all 3 environment science topics assessed in TIMSS are not included in the Korean science curriculum through 8th grade, even though they are included in most other participating nations' curricula. The average percent correct of items was analyzed according to the main topic, the item type and the cognitive domain. Items that showed differences between the average percent correct of Korea and the international average as well as differences between the average percent correct of boys and girls were further analyzed. Results revealed that Korean students performed better than the international average, especially in 'use and conservation of natural resources', multiple-choice items, and items requiring 'factual knowledge'. Also, male students demonstrated significantly higher achievement than female students. On the other hand, Korean students showed relatively lower achievement in constructed-response items, items that contained content they had not learned in science lessons and items requiring descriptions of the uses and effect of science and technology. Moreover, Korean student lacked understanding about acid rain, global warming, and ozone layer destruction. Korean female students showed relatively lower environmental conceptions and lower performance on items requiring data analysis than Korean male students. On the basis of these results, this study suggested that topics of environmental science be included in the science curriculum and taught in the science classroom to help middle school students more fully comprehend environmental issues.