The carbon-based nanostructures are in limelight due to their widespread applications in nano-to-micro-scale technologies. The carbon dots are known for their unique physical, electrical, optical, chemical and biological properties. The carbon dots (CDs) are being produced through several well-developed synthesis methods, one of which is the green sonochemical. This method is preferred over others because it is a green source of energy, facile, fast, low-temperature process, non-toxic and less expensive. Despite the fact of using 90% less energy than other methods, this method has been overlooked in the published literature. It is possible to prepare pure and doped CDs of low toxicity and controlled physicochemical properties through sonochemical method. In recent years, sonochemically produced CDs have been tuned and characterized for a variety of applications. This review has explored the merits and demerits of sonochemical method in comparison to the other methods for the synthesis of pure CDs and their nanocomposites. The role of multiple factors in tailoring the specific parameters of CDs for their application in antibacterial, polymerization, tissue engineering, catalysis, bio-imagining, supercapacitors, drug delivery and electric devices is also elaborated in this review. This review also concludes on future directions in the applications of sonochemically produced CDs.

Needs for more accurate greenhouse gas (GHG) emission estimation are increasing to prepare for post-Kyoto protocol and emission trading starting from 2015 in Korea. Although GHG emission from landfill is relatively low, uncertainty of methane emissions from landfill is very high compared to the other sectors. Moreover, accurate estimation is needed to design landfill gas collection system and energy generation plant. In this paper, we investigated development methodologies of parameters comprising methane generation potential (L0) which is one of key parameters in methane emission estimation models. DOC included four steps including analysis of waste component, water content, organic carbon content, fossil carbon content. Instead of analysis of organic carbon content and fossil carbon content, biochemical analysis, measuring content of cellulose, hemicellulose, and lignin, is used in MELMod, landfill gas generation model in UK. Methodologies to develop DOCF has several methods including batch test, lysimeter test and test cell. They had difference in scale and similarity to landfill, but it is hard to consider the best method at the present stage. Preceding research on MCF is little. Lysimeter test and test cell can be the candidate to develop MCF, because of flexibility on test condition to characterize the structure of landfill sites. F is defined as fraction of methane in landfill gas. But by carbon flow and mass balance, F should represent fraction of methane in biogas generated by anaerobic decomposition. In this definition, F can be derived by same methods to that of DOCF.

P-V 곡선을 적용하여 참취와 수리취의 수분특성인자를 측정한 결과 최대포수시의 삼투포텐셜 ψsato과 초기원형질 분리점의 삼투포텐셜 ψtlpo은 참취가 수리취보다 낮은 값을 나타냈으나 큰 차이를 보이지는 않았다. 최대팽압 ψP,max는 참취가 수리취에 비해 높게 나타났으며, 최대탄성계수 Emax는 참취가 수리취에 비해 약 2.4배 정도 높은 값을 나타냈다. 초기원형질분리점에서의 상대함수율 RWCtlp은 참취와 수리취 모두 90% 이상의 함수율을 보여 비교적 삼투 조절기능이 좋은 것을 알 수 있었고, apoplastic water의 비율은 참취가 더 크며, Vo/DW, Vt/DW, Ns/DW은 수리취가 참취에 비해 약 1.5~2.0배 정도 큰 경향을 보였다. 위 결과를 통해 참취와 수리취 모두 초기원형질분리점과 최대포수시의 삼투포텐셜이 높은 편으로 내건성은 비교적 약한 것으로 나타났으며, 습윤한 지역이 생육에 적합함을 알 수 있었다. 또한, 참취와 수리취를 비교할 때 참취가 수리취에 비해 건성잎의 특성을 가지고 있으며, 최대탄성계수와 삼투포텐셜이 높아 내건성이 약간 더 강한 것을 알 수 있었다.