• 교통기술과정책
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• 제4권3호
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• pp.105-116
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• 2007

Walking is the first thing an infant wants to do and the last thing an old person wants to give up. Walking is the exercise that does not need a gym. It is the prescription without medicine, the weight control without diet, and the cosmetic that can't be found in a chemist. It is the tranquillizer without a pill, the therapy without a psychoanalyst, and the holiday that does not cost a penny. What's more, it does not pollute, consumers few natural resources and is highly efficient. Walking is convenient, it needs no special equipment, is self-regulating and inherently safe. Walking is as natural as breathing. John Butcher, Founder Walk21, 1999.

• Biomolecules & Therapeutics
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• 제11권1호
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• pp.8-32
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• 2003

Garlic(Allium sativum L.) is one of the oldest cultivated plants and has been used throughout the world as food supplement and folk medicine for thousands of years. In modem times a number of garlic derived products are introduced on the market as health food supplement in ever growing scale. In 1844 German chemist Wertheim investigated the garlic first time chemically and thereafter many kinds of organosulfur compounds were isolated and their biological activities were elucidated scientifically. The main biological activities are antibacterial, antifungal, antithrombotic, cholesterol-lowering, antineoplastic and hepatoprotective activities. Chemical works as well as therapeutic and preventive effects of garlic are reviewed.

• 한국응용곤충학회지
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• 제34권1호
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• pp.9-14
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• 1995

From a chemist's perspective, Scarabaeidae is one of the most exciting group of insects to work on the isolation, identification, and synthesis of sex pheromones because-as opposed to Lepidoptera, which by and large utilizes straight chain alcohols, aldehydes, and acetates-the pheromonal chemistry of scarab beetles is remarkably diverse. While species in the subfamily Rutelinae utilize pheromone constituents, which are presumably fatty acid derivatives, the more primitive species in the subfamily Melolonthinae use phenolic, amino acid derivative, and terpenoid compounds. Here, I discuss the recent advances we have accomplished in the identification of scarab sex pheromones with especial emphasis on their chemical diversity. Also, I discuss the potential role of these sex pheromones in insect pest management. Field tests revealed that, in contrast to what has been frequently observed in the Lepidoptera, the higher the dosage of sex pheromone loaded in the traps the greater the capture of scarab beetles. These data suggest that mass trapping is more likely to be useful for scarab pest management than mating distruption.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.7-7
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• 2011

Graphene and graphene derivatives have attracted enormous attention from various research fields for applications in electronic devices, transparent electrodes, biosensors, drug delivery system and surface coatings. In the viewpoint of chemist, the chemical structure of graphene derivatives seems intriguing but detailed structures are being revealed only recently while engineering approaches for various applications are being executed very actively. In addition, cytotoxicity and mammalian cellular responses to graphene have not thoroughly investigated yet in spite of the importance in bio-applications and environment. In this talk, I'll introduce recent studies which report cytotoxicity and behaviors of mammalian cells when the cells are exposed to graphene (as well as some bio-applications of graphene), especially to get closer to answers to these questions, "how we understand and how/why we use graphene in biotechnology".

• International Journal of Advanced Culture Technology
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• 제8권2호
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• pp.28-33
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• 2020

The Chemist Antoine-Laurent Lavoisier and mathematician Pierre Simon Laplace, who conducted a collaborative research on heat phenomena, are two of the key figures that represent French scientific community in the late 18th century. They joined hands together to understand heat phenomena that had not been fully explained until that time. They studied heat phenomena based on a heat particle model called 'caloric' and this study further expanded into light, magnetism and electricity, laying groundwork for many other research achievements afterwards. This article goes through their individual researches and looks into the process of their joint research based on the analysis of their publications. Further to these, it emphasizes its continuity with the Laplacian Program, a large-scale research project conducted in the early 19th century. Lastly, this article presents how science can merge with history, and at the same time, introduces the prerequisites for successful convergence research through existing research cases.

• International Journal of Industrial Entomology and Biomaterials
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• 제8권1호
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• pp.1-15
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• 2004

Due to recent scientific innovations in mulberry cultivation, leaf yield has been increased manifold. However, with successive leaf harvest, a quantum drop in leaf yield and quality has been noted. This inturn has affected the silkworm rearing and farmers suffered by the frequent crop failures. This is mainly due to nutrient deficiencies in mulberry leaf. Moreover, no complete information is available about hunger signs of nutritional disorders, analytical diagnosis and critical levels of nutrients required. The present paper, thus, may serve as an important nutrient guide for identification of hunger signs, leaf nutrients status under deficiency and critical levels of the elements namely N, P, K, Ca, Mg, S, B, Cu, Fe, Mn and Zn requirements for higher leaf yield and quality. The leaf nutrient status provided may help chemist for correcting the soil status. Besides, an integration of mulberry intercropping with legumes and applications of neem and castor oil cakes, VA-mycorrhizal inoculation, biofertilizer and vermicompost are suggested as integrated nutrient management for sustainable sericulture industry. Based on the information described in this paper, a model needs to be framed for maintaining continuous supply of nutrients to obtain desired quantity and quality of mulberry leaf for successful silkworm cocoon crop and increasing overall silk productivity.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2012년도 춘계학술발표대회
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• pp.51-51
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• 2012

There is a growing interest in innovative chemical synthesis in microreactors owing to high efficiency, selectivity, and yield. In microfluidic systems, the low-volume spatial and temporal control of reactants and products offers a novel method for chemical manipulation and product generation. Glass, silicon, poly(dimethylsiloxane) (PDMS), and plastics have been used for the fabrication of miniaturized devices. However, these materials are not the best due to either of low chemical durability or expensive fabrication costs. In our group, we have recently addressed the demand for economical resistant materials that can be used for easy fabrication of microfluidic systems with reliable durability. We have suggested the use of various specialty polymers such as silicon-based inorganic polymers and fluoropolymer, flexible polyimide (PI) films that have not been used for microfluidic devices, although they have been used for other areas. And inexpensive lithography techniques were used to fabricate Lab-on-a-Chip type of microreactors with differently devised microchannel design. These microreactors were demonstrated for various synthetic reactions: liquid, liquid-gas organic chemical reactions in heterogeneous catalytic processes, syntheses of polymer and non-trivial inorganic materials. The microreactors were inert, and withstand even harsh conditions, including hydrothermal reaction. In addition, various built-in microstructures inside the microchannels, for example Pd decorated peptide nanowires, definitely enhance the uniqueness and performance of microreactors. These user-friendly Lab-on-a-Chip devices are useful alternatives for chemist and chemical engineer to conventional chemical tools such as glass.

• 한국조리학회지
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• 제14권1호
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• pp.56-72
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• 2008

Molecular gastronomy is a science that deconstructs the classic haute cuisine and applies science knowledge and laboratory techniques to create textures and flavors in unusual ways. The term 'Molecular Gastronomy' was introduced in 1988 by French chemist 'Herve This' and Oxford physicist 'Nicholas Kurti'. It has since been adopted by both world culinary establishments and scientists, from 'El Bulli' to 'Harold McGee'. Since most world-top prestigious restaurants and chefs were enthralled by this revolunary culinary movement, molecular gastronomy and molecular cooking have drawn a growing interest of lots of Korean people in the food industry until now. However, Korean foodservice industry is unlikely to be ready to develop this advent-garde culinary movement because molecular gastronomy is still an insufficiently established concept of culinary science and philosophy in Korea. Besides, there are many clumsy abuses of putative and clinically unproven bio-chemical components in kitchens and restaurants in the name of culinary science or culinary arts. Such a careless approach and attitude towards an important exercise like a cooking is highly deplorable. Thus it is still too far early to expect the prospective path of molecular gastronomy in Korea without understanding the core principle of molecular gastronomy and having any cultural support.

• 자원리싸이클링
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• 제18권6호
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• pp.3-9
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• 2009

본 총설은 용매추출(또는 액-액 추출)에 대한 일반적인 원리와 추출제별 용매추출 공정의 기초 원리를 소개하고 있다. 용매추출은 서로 섞이지 않는 두 상(phase)간에 화합물이 한 상(phase)에서 다른 상으로 이동하는 현상을 이용하는 공정이다. 초기에는 분석화학 분야에서 용매추출의 간편성, 신속성 및 넓은 적용성 때문에 많이 사용되었으며, 분액깔데기와 같은 간단한 도구로 수분내에 추출실험을 완료할 수 있다는 장점이 있다.

• 한국연초학회지
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• 제32권2호
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• pp.88-94
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• 2010

The ether extract(EE) of leaf tobacco contains diverse compounds such as lipid, resinoid, paraffin hydrocarbons and pigments. Although the correlation of EE concentertion with leaf tobacco has not been established clearly, it is known that in some concentration range, EE concentration of leaf tobacco exerts good influence on the quality of tobacco. Recently, The American Oil Chemist's Society introduced new method(Am 5-04; AOCS, 2009) to determine EE concentration by AT15 extractor. This method is based on extraction with organic solvent at relatively high temperature and pressure, which significantly reduces the extraction time and ensures safety. The aim of this study is to optimize analytical condition of AOCS method for analyzing EE concentration of leaf tobacco. When sample pre-drying time and extraction time of XT15 were set to 3 hour and 30 minute and 30 minute respectively, EE concentration obtained from AOAC method. Statistical analysis(T-test) showed that there is no difference(P>0.05) between EE concentrations from two methods.