Don Park

Tungsten bit line fuse has been used for years in repair application but it fails during BOC (board on chip) package PCT (pressure cooker test) because of its weakness to corrosion. We searched for new material against corrosion, and metal-1 aluminum fuse was set up. Although there is no failure in PCT, we have found a fatal failure in IMD

ABSTRACT Since yeast may be an important microorganism for industrial use when its genes are modified by recombinant DNA techniques to overproduce certain proteins, (particularly those which are glycosylated), it is desirable to study how environmental variables affect its protein secretion ability. It is also of interest to understand how proteins such as proteases, lipases and amylases are excreted in solid matrices to develop a basis for learning more about solid fermentations. With these two applications in mind, the total protein excreted by both aerated and non-aerated Saccharomyces cerevisiae growing in a liquid batch culture (with varying levels of CO2 and NaCl) was tracked. Using a modified Bradford method (Coomassie Blue dye-binding assay) for the concentration of total proteins in the extracellular fermentation broth, it has been determined that by 24 h of the run, excreted proteins rose to levels of about 10% of the total cell protein (500 μg ml−1 protein from about 10 g of yeast, containing about 5 g total protein). No cell lysis was observed during the 24 h run. The highest protein levels at the top of the fermentor seemed to be those achieved in response to CO2 alone. Additions of NaCl did not seem to enhance the secreted protein level. Large inconsistencies in replicating anaerobic runs for protein concentration appeared to be explained by noting that rising CO2 bubbles may cause ‘foam fractionation’ of the proteins in the broth.

In this paper the novel robust Hemispherical Grain (HSG)-merged Al2O3/HfO2 (AHO) capacitor with diagonal cell array scheme and double mold oxide (DMO) is introduced. The capacitor process with diagonal cell array scheme and double mold oxide can maximize storage node (SN) height up to 2.0 mum in 0.11 mum dynamic random access memory (DRAM) technology by enlarging the bottom size

A bee sting can cause a foreign body granuloma of the skin, due to activated macrophages at the stinging site. A 52-year-old woman presented with a large doughnut-shaped ulcerative tumour on the left side of her face. A bean-sized facial papule had grown to a 4.0 x 3.9 x 1.1 cm mass after multiple bee stings induced by herself over a period of 1 year. Histology showed epidermal ulceration with granulomatous inflammatory cell infiltration of many eosinophils. No micro-organisms or foreign bodies were identified. Intralesional triamcinolone acetonide was not effective, but an excellent outcome was obtained using carbon dioxide laser vaporization of the lesion.

In this study, we have synthesized sorbitan acrylate through response surface methodology, using sorbitan and vinyl acrylate that catalyze immobilized lipase. In order to optimize the enzymatic synthesis of the sorbitan acrylate, we applied response surface techniques to determine the effects of five-level-four-factors and their reciprocal interactions with the biosynthesis of sorbitan acrylate. Our statistical model predicted that the highest conversion yield of sorbitan acrylate would be approx 100%, under the following optimized reaction conditions: a reaction temperature of 40.1 degrees C, a reaction time of 237.4 min, an enzyme concentration of 8%, and a 4.49:1 acyl donor/acceptor molar ratio. Using these optimal conditions in three independent replicates, the conversion yield reached 97.6+/-1.3%.

Hydrolytic enzymes such as cellulase and hemicellulase have been attracted in lignocellulose based biorefinery. Especially, mannanase has been a growing interest in industrial applications due to its importance in the bioconversion. In this study, an extracellular endo-β-1, 4-D-mannanase was produced by Streptomyces sp. CS147 (Mn147) and purified 8.5-fold with a 43.4% yield using Sephadex G-50 column. The characterization of Mn147 was performed, and the results were as follows: molecular weight of ∼25 kDa with an optimum temperature of 50 °C and pH of 11.0. The effect of metal ion and various reagents on Mn147 was strongly activated by Ca(+2) but inhibited by Mg(+2) , Fe(+2) , hydrogen peroxide, EDTA and EGTA. Km and Vmax values of Mn147 were 0.13 mg/mL and 294 μmol/min mg, respectively, when different concentrations (3.1 to 50 mg/mL) of locust bean gum galactomannan were used as substrate. In enzymatic hydrolysis of heterogeneous substrate (spent coffee grounds), Mn147 shows a simi...

In this study, the recovery of algal oil from Enteromorpha intestinalis based on an acidic-hydrothermal reaction was investigated. Overall, the algal oil yield after the acidic-hydrothermal reaction was increased under the conditions of high reaction temperature, high catalyst concentration, and long reaction time within the tested ranges. Significantly, catalyst concentration, compared with reaction temperature and time, less affected algal oil recovery. The optimal acidic-hydrothermal reaction conditions for production of algal oil from E. intestinalis were as follows-200 °C reaction temperature, 2.92 % catalyst concentration, 54 min reaction time. Under these conditions, an 18.6 % algal oil yield was obtained. By increasing the combined severity factor, the algae oil recovery yield linearly increased.

We isolated a novel lactic acid bacterium from a Korean traditional fermented food, soybean paste. The newly isolated strain, dubbed RKY2, grew well on glucose, sucrose, galactose, and fructose, but it could not utilize xylose, starch, or glycerol. When the partially amplified 16S rDNA sequence (772 bp) of the strain RKY2 was compared with 10 reference strains, it was found

In this study, three epigallocatechin gallate glycosides were synthesized by the acceptor reaction of a glucansucrase produced by Leuconostoc mesenteroides B-1299CB with epigallocatechin gallate (EGCG) and sucrose. Each of these glycosides was then purified, and the structures were assigned as follows: epigallocatechin gallate 7-O-alpha-D-glucopyranoside (EGCG-G1); epigallocatechin gallate 4'-O-alpha-D-glucopyranoside (EGCG-G1'); and epigallocatechin gallate 7,4'-O-alpha-D-glucopyranoside (EGCG-G2). One of these compounds (EGCG-G1) was a novel compound. The EGCG glycosides exhibited similar or slower antioxidant effects, depending on their structures (EGCG > or = EGCG-G1 > EGCG-G1' > EGCG-G2), and also manifested a higher degree of browning resistance than was previously noted in EGCG. Also, EGCG-G1, EGCG-G1', and EGCG-G2 were 49, 55, and 114 times as water soluble, respectively, as EGCG.

... a monomer in plastics, or as an intermediate in the synthesis of high volume oxy genated chemicals, would cause a significant increase in anticipated demand [2,3,7]. Recently, the scale of lactic acid production has been considerably rising, in order ... 5] Yun, JS, YJ Wee, and HW ...

We developed a process for production of methane at a pilot scale. This process consists of three stages. The first stage is a semianaerobic hydrolysis/acidogenic step in which organic wastes are converted to various sugars, amino acids, and volatile fatty acids (VFAs). Operation temperature and pH were 45 degrees C, and 5.0-5.5, respectively. Hydraulic retention time (HRT) was 2 d. To remove the putrid odor and to enhance the hydrolysis of organic wastes, a mixture of bacteria isolated from landfill soil was inoculated into the reactor. Total chemical oxygen demand (tCOD) and biological oxygen demand (BOD) were 36,000 mg/L and 40,000 mg/L, respectively. The second stage was an anaerobic acidogenic process, which can produce large amount of VFAs including acetate, propionate, butyrate, valerate, and caproate. Operation temperature and pH were 35 degrees C, and 5.0-5.5, respectively. HRT was 2 d. The third stage was a strictly anaerobic methane fermentation step producing methane and carbon dioxide from VFAs. The working volume of upflow anaerobic sludge blanket (UASB) type reactor was 1200 L, and operation temperature and pH were 41 degrees C, and 7.7-7.9, respectively. HRT was 12 d. Seventy two percent of methane at maximum was generated and the yield was 0.45-0.50 m3/kgVS of food wastes. Through the process, 88% of tCOD and 95% of BOD were removed. The wastewater was treated with the biological aerobic and anaerobic filters immobilized with heterotrophic and autotrophic nitrifying and denitrifying bacteria. Ninety percent of total nitrogen (T-N) was removed by this treatment. The residual T-N and total phosphorous (T-P) were removed by the algal periphyton treatment system. The final concentrations of nitrogen and phosphorous in the drain water were 53 and 7 mg/L, respectively.

Hydrogels are materials with the ability to swell in water through the retention of significant fractions of water within their structures. Owing to their relatively high degree of biocompatibility, hydrogels have been utilized in a host of biomedical applications. In an attempt to determine the optimum conditions for hydrogel synthesis by the free-radical polymerization of sorbitan methacrylate (SMA), the hydrogel used in this study was well polymerized under the following conditions: 50% (w/v) SMA as monomer, 1% (w/w) alpha, alpha'-azo-bis(isobutyro-nitrile) as thermal initiator, and 1% (w/w) ethylene glycol dimethacrylate as cross-liking agent. Under these conditions, the moisture content of the polymerized SMA hydrogel was higher than in the other conditions. Moreover, the moisture content of the poly(SMA) hydrogel was also found to be higher than that of the poly(methyl methacrylate [MMA]) hydrogel. When the Fourier transform-infrared spectrum of poly(SMA) hydrogel was compared with that of poly(MMA) hydrogel, we noted a band at 1735-1730/cm, which did not appear in the Fourier transform-infrared spectrum of poly(MMA). The surface of the poly(SMA) hydrogel was visualized through scanning electron microscopy, and was uniform and clear in appearance.