• Journal of Sericultural and Entomological Science
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• v.17 no.1
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• pp.35-39
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• 1975

The acid treatment hatching method has been used practically for about 60 years and a number of investigators have studied about the artificial hatching for silkworm e99s, but the basic theory about the acid treatment hatching is not clarified yet. It is no exaggeration to say that the accidents of non hatching is continued ceaselessly in the silkworm egg by hydrochloric acid treatment. It is believed that the accident is due to the adulterants in HCl lather than inattention of acid treatment. Therefore, the authors mixed hydrochloric acid (analytical grade) with or added it to chemical ingredients which are possible to be included in the process of hydrochloric acid production, and treated it to summer and fall silkworm egg. The metalic adulterants such as iron, mercury, lead and arsenic are appeared not to be worried, but damage of SO$_3$ and free chlorine is seemed to lie considerable. Therefore, before acid treatment for hatching hydrochloric acid was warmed to 50$^{\circ}C$ with shaking to evaporate several injurious gases, by whick the damage due to use of hydrochloric acid for acid treatment hatching is prevented considerably. In conclusion, it is recommended to pretest bioassay with every HCl samples before artificial hatching of silkworm egg.

• Applied Biological Chemistry
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• v.36 no.2
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• pp.86-92
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• 1993

Myrosinase from radish was purified by DEAE Bio-Gel, Con-A, and Superose-6 column. The purified myrosinase(II) possessed 2 subunits, and their molecular as determined by SDS-polyacrylamide gel electrophoresis were 53 and 39 KD, respectively. The specific activity of purified enzyme was 37,500 units/mg. The enzyme was purified approximately 44-fold compared to the crude enzyme. Optimum pH of the myrosinase was $6.5{\sim}7.0$ in phosphate and Tris-HCl buffer solutions. Optimum temperature of the enzyme was $37{\sim}38^{\circ}C$. The enzyme was stable at pH 7.0, and less than $30^{\circ}C$. Cu or Hg ion significantly inhibited the enzyme activity, but ascorbic acid enhanced, resulting in a maximum activity by 1 mM ascorbic acid. Among the ascorbic acid analogues, dehydroascorbic acid did not affect, whereas others showed a little effect, but less than ascorbic acid itself. Individual 2-mercaptoethanol and dithiothreitol (reducing agents) did not enhance the enzyme activity. but 2-mercaptoethanol effect was enhanced when mixed with ascorbic acid.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.277-282
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• 1997

Acetolactate synthase (ALS) was partially purified from Escherichia coli MF2000/pTATX containing Arabidopsis thaliana ALS gene. The partially purified ALS was examined for its sensitivity toward various modifying reagents such as iodoacetic acid, iodoacetamide, N-ethylmaleimide (NEM), 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB), p-chloromercuribenzoic acid (PCMB), and phenylglyoxal. It was found that PCMB inhibited the enzyme activity most strongly followed by DTNB and NEM. Since iodoacetic acid did not compete with substrate pyruvate, it appeared that cysteine is not involved in the substrate binding site. On the other hand, the substrate protected the enzyme partly from inactivation by phenylglyoxal, which might indicate interaction of arginine residue with the substrate. The partially purified enzyme was inhibited by end products, valine and isoleucine, but not by leucine. However, the ALS modified with PCMB led to potentiate the feedback inhibition of all end products. Additionally, derivatives of pyrimidyl sulfur benzoate, a candidate for a new herbicide for ALS, were examined for their inhibitory effects.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.107-112
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• 2002

Seasonal occurrence pattern of the peach pyramid moth (PPM), Dichocrosis punctfferahs, was studied by sex pheromone traps and mercury light traps in several Fuyu persimmon orchards under different control pressures in southern region of Korea in 2000 and 2001. Fruit damage by the larvae was also checked at harvesting time from 1999 to 2001. The pattern showed 3 distinct peaks; the 1st one in mid to late June, the 2nd one in mid to late August, and the 3rd one in late September. Number of PPM catches was higher in less controlled than in intensively controlled orchards. There were no persimmon fruits damaged by the larvae of PPM and persimmon fruit moth, Stathmopoda masinissa, in our samples from the testing orchards at harvesting time. Therefore, it is unlikely that these two quarantine pests are included in the exporting fruits. Considering flora adjacent to the tested orchards and zero levels of fruit damage by the larvae, there is a strong possibility that the moths flew from neighbouring chestnut trees or other host plants to be attracted to the traps in the persimmon orchards.

• Journal of the Korean Chemical Society
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• v.31 no.5
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• pp.444-451
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• 1987

The dependence of polarographic parameters on the pressure for the reduction of copper(II), cadmium(II), and zinc(II) complex ions with ethylenediamine, propylenediamine, and diethylenetriamine has been studied. In this study the dropping mercury electrode, the mercury pool electrode, and helix type of platinum wire were used as the working, the reference, and the auxilary electrode, respectively. With increasing the pressure from 1 atmosphere to 1,500 atmospheres, the reduction half-wave potentials of metal complex ions are shifted to the negative values and the diffusion currents become considerably larger, in keeping with the theory on the change of the physical properties of the electrolytic solution such as the density, the viscosity, the dielectric constant, and the electrical conductance, etc. The slope values of the logarithmic plot are increased with increasing the pressure, which indicates the more irreversible reduction. The temperature coefficients of diffusion current observed over the range of the temperature from 25$^{\circ}$C to 35$^{\circ}$C are about two percentage with increasing the pressure, therefore the polarographic reduction under the high pressure is controlled by diffusion. The linear relationships between diffusion current and concentration of metal complex ions are established over all pressure range.

• Korean Journal of Organic Agriculture
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• v.14 no.4
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• pp.433-443
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• 2006

With treatment of Kitosan, Wood vinegear and EM(effective microoganism) which farmers call it as substance in fertilizing, conditioning and disease control substances, authors in vestigated on microorganisms change in soil and ealy growth characteristics of tomato. The results were summarized as follows: Among foliar application of kitosan, wood vinegear and EM(effective microoganism) treatments diluted by chitosan 500 times solution level was effective considering growth of tomato as compared other dilutions and control plot. Change of microorganism number in the soil for cultivation of tomato was increased with microorganism treatment plot as compared with control plot. Specially chitosan 500 times solution level showes the most significant effect.

• Journal of radiological science and technology
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• v.33 no.2
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• pp.121-126
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• 2010

Traditionally, lead has been primarily used to shield the radiation in the hospital, because of its soft texture, durability and cost effectiveness. However, lead can be dangerous because of its toxicity when exposed to the human body, and it is classified as a heavy metal like cadmium, mercury, and arsenic etc. In order to compensate its noxious properties on the human body, researchers are trying to develop a radiation shield which has similar shielding efficiency and can also be manufactured in any form. In this study, sulfuric acid barium was mixed with fiber, rubber, and silicon all of which are harmless to the human body, tested, and evaluated for its ability of medical radiation shield. The result of this study showed that the sheet containing silicon and barium has the strongest shielding abilities.

• Analytical Science and Technology
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• v.14 no.3
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• pp.253-258
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• 2001

This is a research on hazardous characteristics and potentials of bottom ash from 9 municipal solid waste combustors(200 tons/day) of Korea by the test methods of leaching and content. The leaching method was performed by Waste Test Method of Korea. In case of the content method, mercury was determined by thermal decomposition amalgamation atomic absorption spectrometer, other 9 elemets including Pb, which were pretreated by U.S.EPA SW-846 3050B method, were determined by flame atomic absorption spectrometer(FAAS) or inductively coupled plasma atomic emission spectrometer(ICP-AES). Results of leaching test showed that Pb and Cu was main pollutants. It was interested that the distribution rate of metals' contents of each combustors was similar and the rank of concentration was Fe>Zn>Cu>Mn>Pb>Cr>As>Cd>Hg.

• Analytical Science and Technology
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• v.8 no.3
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• pp.265-272
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• 1995

Schiff base ligand columns and glow discharge detector have been developed for the trace analysis of metal ions desolved in water. Various types of hydrazide Schiff base ligands have been used and, additionally, they were examined as a filling material of a HPLC column. The hydrazide Schiff base ligands used were N, N'-oxalybis(salicylaldehydrazone) (OBSH), N, N'-malonylbis(salicylaldehydrazone) (MBSH), and N, N'-succinylbis(salicylaldehydrazone) (SBSH). A mixture of Schiff base ligand and poly(styrene divinylbenzene) was examined and it showed a smooth flow of solution. The OBSH-polymer column demonstrated different effluent factors for different metal ions. Metal ions in eluates were detected by Hollow Cathode Glow Discharge-Atomic Emission Spectrometry(HCGD-AES). HCGD-AES showed good sensitivity and selectivity. This is only the preliminary results of new OBSH-polymer column and glow discharge detector.

• International Area Studies Review
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• v.14 no.1
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• pp.77-97
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• 2010

Recently, countries on the Caspian Sea were had heavily interested due to instability of international resource market. These countries having been developed basing on energy exports, especially Kazakhstan have drastically grown during a decades. However economy, heavily relied on the exports of energy, is influenced on fluctuation in the international energy price as well as sometimes exposed at Dutch disease. These days, Kazakhstan, increased trade and investment with Korea, has been on the rise as new supplier for energy. Therefore, economic change in Kazakhstan can be an important issue. In this paper, we analyze relations among oil price, interest rate, and real exchange rate during sample period from January 1999 to December 2008 expanding Balasa-Samuelson model. Empirical results present that oil price, interest rate, and real exchange rate mutually keep their balance. Eventually, we find out Kazakhstan has exposed at Dutch disease since oil price and interest rate have negative impacts on real exchange rate respectively.