• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3730-3734
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• 2010

A simple, inexpensive and less time consuming electrochemical methods were carried out to prepare ordered mesoporous cobalt films. Ordered mesoporous cobalt films were successfully synthesized by templated electrodepostion of hexagonal $H_1$-e Co ion. The electrodeposited mesopores films were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), low angle X-ray diffraction (XRD) and voltammetric methods. The applicability of thin films as high - performance super capacitors electrode materials is demonstrated electrochemically using cyclic voltammetry (CV) technique.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3653-3657
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• 2010

Silica supported tungstosilicic acid has been used as an effective catalyst for a modified Dakin-West one-pot, four-component condensation of an aryl aldehyde, an aryl ketone, acetyl chloride and acetonitrile for the synthesis of $\beta$-acetamido ketones. This catalytic system can act as an active, inexpensive, recoverable and recyclable catalyst. Some advantages of this system are short reaction times, good to excellent yields, easy work up and the ability to be carried out at the large scale reactions.

• Bulletin of the Korean Chemical Society
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• v.30 no.4
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• pp.825-828
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• 2009

Alum $(KAl(SO_4)_2{\cdot}12H_2O)$ is an inexpensive, efficient, non‐toxic and mild catalyst for the synthesis of bis(indolyl)methanes by the reaction of 1H-indole with various aldehydes/ketones under the influence of ultrasound irradiation in solvent‐free condition. The remarkable advantages of this method are the simple experimental procedures, shorter reaction times, high yields of product and green aspects by avoiding toxic catalysts and solvents.

• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2532-2534
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• 2009

A facile and efficient synthetic route has been developed for the polyhydroquinoline via four component reactions of aldehydes, dimedone, ethyl acetoacetate and ammonium acetate in the presence of catalytic amount of scolecite in ethanol at 70 ${^{\circ}C}$ through Hantzsch reaction. This method gives remarkable advantages such as simple work-up procedure, environmentally friendly, inexpensive, non-toxic and recyclable catalyst, shorter reaction time along with excellent yields.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.585-589
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• 2013

Optically active N-benzyl-2-methyl-2H-benzo[b][1,4]oxazin-3(4H)-ones and N-benzyl-2-methyl-2H-benzo[b][1,4]thiazin-3(4H)-ones with potential synthetic and pharmacological interest were prepared via Smiles rearrangement in conventional as well as microwave irradiation conditions in one-pot from inexpensive (S)-2-chloropropionic acid. Most of the compounds displayed good inhibition against Gram positive bacteria and fungi in the antibiotic test.

• Journal of the Korean Chemical Society
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• v.57 no.6
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• pp.691-696
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• 2013

Black carbon contributes to global warming and melting of polar ice as well as causing respiratory diseases. However, it is also an inexpensive, easily available carbon nano material for elementary chemistry experiments. In this study, black carbon samples collected from candle light and automobile exhaust pipes have been investigated to examine their compositions and surface characteristics. The observed broad G and D bands and amorphous $sp^3$ band in their Raman spectra as well as the high intensity of the D (defect) band reveal that black carbon is principally made of amorphous graphite. The black carbon deposits in automobile exhaust pipes are apparently more amorphous, probably due to the shorter time allowed for formation of the carbonaceous matter. An exceptionally large water contact angle ($159.7^{\circ}$) is observed on black carbon, confirming its superhydrophobicity. The surface roughness evidently plays an important role for the contact angle much larger than that of crystalline graphite ($98.3^{\circ}$). According to the Sassie-Baxter equation, less than 1% the area actually in contact with the water drop.

• International Journal of CAD/CAM
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• v.2 no.1
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• pp.29-37
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• 2002

De-manufacturing is an entire process of collecting, disassembling, reusing, refurbishing, recycling, and/or disposing products that are obsolete or un-repairable. Designing the products for inexpensive and efficient disassembly enhances the ease of de-manufacturing. Virtual disassembly addresses the difficulty and the methods to disassemble a product in design stage rather than really disassemble a product at the end of its life cycle. Based on the virtual disassembly analysis results, design will be improved for better assembling/disassembling. This paper presents a systematic virtual disassembly methodology such as disassembly relation modeling, path/sequence automatic generation and evaluation. This paper also presents a new virtual disassembly interface paradigm via virtual reality technology for disassembly simulation in virtual environment.

• Solar Energy
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• v.19 no.1
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• pp.9-17
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• 1999

An Experimental study on the boiling and condensation heat transfer performance of thermosyphons with low intergral-fins was performed to investigate its heat transfer characteristics. A plain thermo syphon having the same inner and outer diameter as the finned thermosyphons was also tested for comparison. Water and CFC-30 was used as working fluids. The experimental results have been assessed and compared with same existing theories. Good agreement with the theories of Imura and Nusselt was obtained. The vertical closed-type thermosyphons with low integral-fins gave significant increases in the overall heat transfer coefficient compared to plain thermosyphon. In addition, the overall heat transfer coefficients and the operating characteristics was obtained as a function vof operating temperature for the practical applications. Also, the closed two-phase thermosyphons with low integral-fins would be highly recommended to achieve some inexpensive and compact heat exchangers in the range of low temperatures.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.834-837
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• 1993

This paper describes the implementation of an autonomous fuzzy logic controller. The controller is endowed with basic control principles and learning constructs which enable it to autonomously modify its control policy based on system performance. The controller lies dormant when system response is satisfactory but if rapidly initiates adaptation in real time when adverse performance is observed. The autonomous fuzzy controller is implemented on an Intel MCS-51 series micro-controller board using an inexpensive 8-bit Intel 8031 processor. The 11.06 MHz micro-controller operates at a rate exceeding 200 "global" look-up table reinforcements per second. This is important when developing practical on-line adaptive controllers for fast systems. It is also significant because an initial controller look-up table could be incorrect or non-existent. The relatively high learning rate enables the controller to learn to control a system even while it is controlling it.

• KSBB Journal
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• v.31 no.1
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• pp.46-51
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• 2016

Recently paper based diagnostic kits have drawn great interest in the point-of-care testing market (POCT). The paper based detection systems provide inexpensive, rapid and safe analyses for disease markers and/or pathogens. Vitamin C (i.e., ascorbic acid) regulates body's immune system as an antioxidant agent. Humans, however, do not have enough amounts of enzymes involved in the synthesis of vitamin C that it is required to be obtained from their diets (e.g., beverages and/or supplements). Here, we have prepared a paper based kit to detect the concentration of Vitamin C presented in commercially available beverages. The evaluation provides the fast, simple and accurate results for detecting Vitamin C in the prepared paper based kit.