• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.3
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• pp.66-73
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• 2003

Alkaline cellulolytic enzymes are prepared from Coprinus cinereus 2249. Recovery method of enzyme protein from cultured medium and effect factors on enzyme activity of protein were investigated. The results could summarized as follows, \circled1 Amount of enzyme protein from cultured medium was highest in incubation with shaking and addition of skim milk. \circled2 Protein from cultured medium was alkaline enzymatic protein which shows the highest activity at pH 9.0. \circled3 The most effective recovery method of enzyme protein was the precipitation of protein by addition of cultured medium of protein in ethanol. \circled4 The enzyme activity was enhanced by tween-80 and decreased with $Al_2(SO_4)_3$, $H_2O_2$et al, and was little changed with metal ions except $Hg^{++}$.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.8
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• pp.1060-1068
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• 1998

The effects of various catalysts and softners on the anti-crease finish of ramie with glyoxal were investigated. A number of metal salts commonly used as Lewis acid catalysts in DP finishing of cotton with formaldehyde and N-methylol agents were screened for glyoxal treatment of ramie fabric. Various organic and inorganic acids were mixed with Lewis acid catalyst as co-catalysts to improve catalytic activity. As a result, the combination of aluminum sulfate and citric acid was proven highly effective in catalyzing the crosslinking of ramie cellulose by glyoxal under lower curing temperature. With a mixed catalyst, performance properties, such as whiteness and tearing strength as well as wrinkle recovery of treated ramie fabric were improved as compared with that treated with aluminum sulfate alone. Additional improvement of tearing strength and wrinkle recovery was achieved by applying silicons softner in the treatment bath.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.7
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• pp.994-1001
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• 2000

The dynamic behavior of a single-pressure heat recovery steam generator and turbine system for the combined cycle power plant is simulated on the basis of one-dimensional unsteady governing equations. A water level control and a turbine power control are also included in the calculation routine. Transient response of the system to the variation of gas turbine exit condition is simulated and effect of the turbine power control on the system response is examined. In addition, the effect of the treatment of inertia terms(fluid inertia and thermal inertia of heat exchanger metal) on the simulated transient response is investigated.

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.210-218
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• 2018

Ethylenediaminetetraacetic acid (EDTA)-functionalized KIT-6 and KCC-1 mesoporous silicas were prepared via post-synthesis grafting and examined for their ability to promote the recovery of rare earth metal ions such as $Nd^{3+}$ from an aqueous medium. The obtained adsorption isotherms were fitted to the Langmuir model, which gave a maximum adsorption of $Nd^{3+}$ ions of 109.8 and 96.5 mg/g for KIT-6-EDTA and KCC-1-EDTA, respectively, at $25^{\circ}C$ and pH 6. The adsorption kinetic profile of KIT-6 was faster than KCC-1. KIT-6 was also proved to be more stable against desorption under acidic regeneration conditions.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.10a
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• pp.241-244
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• 2009

This paper deals with a usefulness verification of stretch forming process using flexible die. The stretch forming method is widely used in aircraft and high-speed train industries for manufacturing of skin structure, which is made of sheet metal. A great number of solid dies are originally used and developed for specific shapes with respect to different curvature radii of the skin structures. Accordingly, flexible stretch forming process is proposed in this study. It replaces the conventional solid dies with a set of height adjustable discrete punches. A usefulness of the flexible die is verified through extensive numerical simulations of the stretch forming process for simply curved sheet plate. The elastic recovery is considered and formability evaluations are conducted through a comparison of symmetry plane configurations.

• Journal of Industrial Technology
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• v.21 no.A
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• pp.257-261
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• 2001

The separation of rare earths minerals is very difficult because of their similar chemical properties. The rare earth minerals are used as the mixed rare earth minerals or the misch metal without separation to each element. However, the high purity rare earths are recently produced commercially to each element so they there are used as the materials for high tech. Based on the characterization results for the raw minerals, we have developed a combined process containing gravity seperation, magnetic seperation and flotation. The result obtained from this study is monazite concentration of TREO grade 69.11% and Recovery 56.02%.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.1185-1188
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• 2003

This paper describes a design for a 2.5Gb/s serial data link CMOS transceiver based on the InfiniBand$^{TM}$ specification. The transceiver chip integrates data serializer, line driver, Tx PLL, deserializer, clock recovery, and lock detector. The designed transceiver is fabricated in a 0.25 ${\mu}{\textrm}{m}$ CMOS mixed-signal, 1-poly, 5-metal process. The first version chip occupies a 3.0mm x 3.3mm area and consumes 450mW with 2.5V supply. In 2.5 Gbps, the output jitter of transmitter measured at the point over a 1.2m, 50Ω coaxial cable is 8.811ps(rms), 68ps(p-p). In the receiver, VCO jitter is 18.5ps(rms), 130ps(p-p), the recovered data are found equivalent to the transmitted data as expected. In the design for second version chip, the proposed clock and data recovery circuit using linear phase detector can reduce jitter in the VCO of PLL.L.

• JSTS:Journal of Semiconductor Technology and Science
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• v.3 no.4
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• pp.188-193
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• 2003

This paper describes a novel burst-mode clock and data recovery (CDR) circuit which can be used for 622Mbps burst mode applications. The CDR circuit is basically a phase locked loop (PLL) having two phase detectors (PDs), one for the reference clock and the other for the NRZ data, whose operations are controlled by an external control signal. This CDR was fabricated in a 1-poly 5-metal $0.25{\;}\mu\textrm{m}$ CMOS technology. Jitter generation, burst/continuous mode data receptions were tested. Operational frequency range is 320Mhz~720Mhz and BER is less than 1e-12 for PRBS31 at 622Mhz. For the same data sequence, the extracted clock jitter is less than 8ps rms. Power consumption of 100mW was measured without I/O circuits.

• Resources Recycling
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• v.12 no.2
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• pp.21-27
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• 2003

Smelting reduction technique in arc furnace was applied for the recovery of valuable metal such as V from LD slag. In the present study, the parameters for increasing the reduction rate and the reduction efficiency were selected by changing the oxide additives, melting temperature and basicity. The optimum condition for LD-slag reduction was achieved by $Al_2$$O_3$ addition. The reduction ratio of V was increased in increasing the basicity.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.597-598
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• 2006

Gas filtration at high temperature from industrial processes offers various advantages such as increasing process efficiency, improving heat recovery and materials resource recovery, etc. At the same time, it is an advanced environment protection technology. This paper describes a newly developed metallic filter element. The manufacturing process of sintered $Fe_3Al$ metallic powder and the mechanical and filtration characteristics of this filter element were investigated. In this work, the phase constituent changes of the $Fe_3Al$ powder during sintering were studied. The newly developed filter elements were found to have excellent corrosion resistance, good thermal resistance, high strength and high filtration efficiency.