• Korean Journal of Soil Science and Fertilizer
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• v.36 no.3
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• pp.134-144
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• 2003

A rhizobacterium Pseudomonas cholororaphis O6 produced several secondary metabolites, such as phenazines, protease, and HCN that may be involved in inhibition of the growth of phytopathogenic fungi. In field study, P. chlororaphis O6 treatment on wheat seed suppressed root rot disease caused by Fusarium culmorum. The major organic acids of cucumber root exudates were fumaric acid, malic acid, benzoic acid, and succinic acid. Glucose and fructose were major monosaccharides in cucumber root exudates. The total amount of organic acids was ten times higher than that of the sugars. P. chlororaphis O6 grew well on cucumber root exudates. The dctA gene of P. chlororaphis O6 consisted of a 1,335 bp open reading frame with a deduced amino acid sequence of 444 residues, corresponding to a molecular size of about 47 kD and pI 8.2. The deduced dctA sequence has ten putative transmembrane domains, as expected of a membrane-embedded protein. Our results indicated that organic acids in cucumber root exudates may play an important role in providing nutrient source for root colonization of biological control bacteria, and the dctA gene of P. chlororaphis O6 may be an important bacterial trait that is involved in utilization of root exudates.

• Journal of Nutrition and Health
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• v.19 no.4
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• pp.246-254
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• 1986

Weanling female Sprague Dawley rats were fed d diets containing 22mg pyridoxine. BCI/kg diet (control diet) and l.2mg pyridoxine. BCI/kg diet (deficient diet). One control group and one defi­c dent group were fed their diet throughout growth, g gestation and lactation. After the pups were born and weaned, the deficient group was divided into two groups. One switched to control diet(supple­I mented group) and the other continued the same d deficient diet( deficient group) until 10 week -old. The liver mitochondrial and cytosolic asparate a aminotransferase activity and pyridoxal phosphate content were determined in offspring rats. The aspartate aminotransferase activities in both liver mito$\phi$ondrial and cytosolic fractions of den­d cient group were significantly lower than those of controls, but there were no significant differences between two groups after addition of 1O^{-4}M pyri­d do뼈I phosphate to the medium. By pyridoxine s supplementation after weaning, the reduced aspar­a tate aminotnmsferase activities were only partialy I restored to control levels. The pyridoxal phospha­t te content of deficient group in Iiver mitochondr­ial and cytosoIic fractions were alo significantly different from those of controls, but readily restored by dietary supplementation. These results suggest that there is a quantitative and a qualitative changes of aspartate amino trans­f ferase and pyridoxal phosphate in liver mitochon­d drial and cytosolic fraction by long-term pyrido­x xine deficiency and these reductions can partially recovered by dietary pyridoxine supplementation after weaning.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.9
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• pp.1226-1230
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• 2005

The present investigation was undertaken to study the genetic polymorphism of the DRB3 exon 2 in 75 crossbred cattle by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Five genotypes i.e. HaeIII-a, HaeIII-b, HaeIII-e, HaeIII-ab and HaeIII-ae were observed when the 284 bp PCR products were digested with HaeIII restriction enzyme. The corresponding frequencies of these patterns were 0.53, 0.04, 0.01, 0.38 and 0.04, respectively. Digestion with RsaI restriction enzyme resolved 24 different restriction patterns. The frequencies of these patterns ranged from 0.013 (RsaI-f, RsaI-k and RsaI-c/n) to 0.120 (RsaI-n). The results revealed that the crossbred cows belonged to the RsaI patterns namely b, k, l, a/l, d/s, l/n, l/o and m/n, whose corresponding frequencies were 0.027, 0.013, 0.040, 0.027, 0.040, 0.067, 0.027 and 0.067, respectively. Digestion of the 284 bp PCR product of DRB3.2 gene with PstI in the crossbred cattle did not reveal any restriction site. These results suggested the absence of the recognition site in some of the animals. These results also revealed that the crossbred cows studied were in homozygous as well as heterozygous condition. On the basis of the above results it can be concluded that the DRB3.2 gene was found to be highly polymorphic in the crossbred cattle population.

• Journal of environmental and Sanitary engineering
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• v.18 no.4
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• pp.52-63
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• 2003

This paper investigated Taxi drivers physical subjective symptoms and what factors were interviewed caused the symptoms. The 600 owning taxi-drivers in Seoul during four months from August 1st, 2003 to November 30th, 2003. 1. The average age of the owning taxi-drivers was generally quite high 54 years old. It was very high index compared with the Todai Health Index(THI) and Cornell Medical Index(CMI) of health check tables. 2. According to the age in THI health check table, the complains of mental subjective symptom by reason of age was high among 31 to 40 years old. People who belonged that age group showed high fabrication(L), digestion(C) and aggressiveness(F). The results showed the complains of mental subjective symptom. All items except tiredness(I), melancholia(N), and hypersensitivity(P) were commonly reported by people in their sixties. On the other hand, melancholia(N) and hypersensitivity(P), people in their forties were investigated highly. Statistically, the items of heartㆍblood stream(C) and digestion(D) systems were similar between the two ages, but anger(Q) was different. (p<0.05) 3. From the complains of mental and physical subjective symptoms about work satisfaction on the THI health check table, all items except eyeㆍskin trouble(B) showed strong dissatisfaction. From the complains of mental and physical subjective symptoms about work satisfaction on the CMI health check table, the items of respiratory system(B), digestion(D), nervous system(G), miscellaneous(K), inadequancy(M), and anger(Q) showed similar results. Otherwise, heartㆍblood stream(C) showed statistically different. 4. From the complains of mental and physical subjective symptoms on salary satisfaction in the THI health check table, in the case of people receiving around 1 million won, the complains of physical symptoms showed high among all items except for the respiratory(A) and digestion(C) systems. The eyeㆍskin trouble(B) item showed statistical similarity. The complains of mental and physical subjective symptoms according to a salary degree on the CMI health check table was completely different from the above results. In people received around 1~1.5million won, all items except anxiety(O) showed high. The hypersensitivity(P) item showed statistically different.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.363-363
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• 2008

The development of dry etching process for sapphire wafer with plasma has been key issues for the opto-electric devices. The challenges are increasing control and obtaining low plasma induced-damage because an unwanted scattering of radiation is caused by the spatial disorder of pattern and variation of surface roughness. The plasma-induced damages during plasma etching process can be classified as impurity contamination of residual etch products or bonding disruption in lattice due to charged particle bombardment. Therefor, fine pattern technology with low damaged etching process and high etch rate are urgently needed. Until now, there are a lot of reports on the etching of sapphire wafer with using $Cl_2$/Ar, $BCl_3$/Ar, HBr/Ar and so on [1]. However, the etch behavior of sapphire wafer have investigated with variation of only one parameter while other parameters are fixed. In this study, we investigated the effect of pressure and other parameters on the etch rate and the selectivity. We selected $BCl_3$ as an etch ant because $BCl_3$ plasmas are widely used in etching process of oxide materials. In plasma, the $BCl_3$ molecule can be dissociated into B radical, $B^+$ ion, Cl radical and $Cl^+$ ion. However, the $BCl_3$ molecule can be dissociated into B radical or $B^+$ ion easier than Cl radical or $Cl^+$ ion. First, we evaluated the etch behaviors of sapphire wafer in $BCl_3$/additive gases (Ar, $N_2,Cl_2$) gases. The behavior of etch rate of sapphire substrate was monitored as a function of additive gas ratio to $BCl_3$ based plasma, total flow rate, r.f. power, d.c. bias under different pressures of 5 mTorr, 10 mTorr, 20 mTorr and 30 mTorr. The etch rates of sapphire wafer, $SiO_2$ and PR were measured with using alpha step surface profiler. In order to understand the changes of radicals, volume density of Cl, B radical and BCl molecule were investigated with optical emission spectroscopy (OES). The chemical states of $Al_2O_3$ thin films were studied with energy dispersive X-ray (EDX) and depth profile anlysis of auger electron spectroscopy (AES). The enhancement of sapphire substrate can be explained by the reactive ion etching mechanism with the competition of the formation of volatile $AlCl_3$, $Al_2Cl_6$ or $BOCl_3$ and the sputter effect by energetic ions.

• Magazine of the Korean Society of Agricultural Engineers
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• v.26 no.1
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• pp.29-37
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• 1984

This study was made to find several significant relations among various physical and mechanical properties including cone penetration resistance. The alluvial clay samples were taken at the Daebul Reclaimed Tideland in Samhomyeon, Yeongamgun, Jeonranamdo. The results of the study are summarized as follows; 1.Most samples belong to medium or high plastic, inorganic, silty clay(clay contents;32-64%, silt contents; 36-68%, sand contents; 0-3%). The specific gravities range from 2.70 to 2.73, the unit weights from 1.45 to 1. 75g/cm$^3$, the natural moisture contents from 45 to 77%, the liquid limits from 32 to 56%. It is certain that the foundation is weak because the natural moisture contents are much higher than the liquid limits. 2.It is known from the shear tests that the unconfined compression strenghs vary from 0.09 to 0. 38kg/cm2, the cohesions from 0.05 to 0. 21kg/cm2, the internal friction angles from 0 to 3˚. 3.The consolidation tests show that the initial void ratios range from 1.25 to 2.28, the compression indeices from 0.43 to 0.84, the preconsolidation loads from 0.21 to 0.74kg/cm$^2$. 4.Cone penetration resistances are usually less than 5kg/cm$^2$ from ground surface to the depth of about 8m, and from S to l0kg/cm$^2$ in the layer below about 8m to hard layer. 5.The cohesion and cone penetration resistance are in proportion to the depth of soil layer. 6.The correlations between various physical and mechanical properties including cone penetration resistance for the alluvial clay samples are as follows; a) Wn=0.944C+ l2.733 (r=0.829) b) LL=0. 728Cy+6. 991 (r=0. 873) c) PI=0.659Cy-8.168 (r=0.860) d) rt=0. 0077(272-Wn) =2.092-0. 0077Wn (r=0. 859) e) 60=0. 035wn-0 447 (r=0. 893) f) C=0.380qw+0.031 (r=0.816) g) qu=0.0707qc+0.029 (r=0.810) h) C=0.018Z+0.055 (r=O.802) I) qc=0. 415Z+1, 438 (r=0. 943)

• Journal of the Earthquake Engineering Society of Korea
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• v.24 no.6
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• pp.253-266
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• 2020

The extended slip-weakening model was investigated by using a compiled set of source-spectrum-related parameters, i.e. seismic moment M_o, S-wave velocity V_s, corner-frequency f_c, and source-controlled high-cut frequency fmax, for 113 shallow crustal earthquakes (focal depth less than 25 km, M_W 3.0~7.5) that occurred in Japan from 1987 to 2016. The investigation was focused on the characteristics of stress drop, radiation energy-to-seismic moment ratio, radiation efficiency, and fracture energy release rate, G_c. The scaling relationships of those source parameters were also investigated and compared with those in previous studies, which were based on generally used singular models with the dimensionless numbers corresponding to f_c given by Brune and Madariaga. The results showed that the stress drop from the singular model with Madariaga's dimensionless number was equivalent to the breakdown stress drop, as well as Brune's effective stress, rather than to static stress drop as has been usually assumed. The scale dependence of stress drop showed a different tendency in accordance with the size category of the earthquakes, which may be divided into small-moderate earthquakes and moderate-large earthquakes by comparing to M_o = 10¹⁷~10¹⁸ Nm. The scale dependence was quite similar to that shown by Kanamori and Rivera. The scale dependence was not because of a poor dynamic range of recorded signals or missing data as asserted by Ide and Beroza, but rather it was because of the scale dependent V_r-induced local similarity of spectrum as shown in a previous study by the authors. The energy release rate G_c with respect to breakdown distance D_c from the extended slip-weakening model coincided with that given by Ellsworth and Beroza in a study on the rupture nucleation phase; and the empirical relationship given by Abercrombie and Rice can represent the results from the extended slip-weakening model, the results from laboratory stick-slip experiments by Ohnaka, and the results given by Ellsworth and Beroza simultaneously. Also the energy flux into the breakdown zone was well correlated with the breakdown stress drop, ${\tilde{e}}$ and peak slip velocity of the fault faces. Consequently, the investigation results indicate the appropriateness of the extended slip-weakening model.

• Bulletin of the Korean Chemical Society
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• v.28 no.2
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• pp.251-256
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• 2007

The crystal structure of fully dehydrated partially Cs+-exchanged zeolite X, [Cs52Na40Si100Al92O384], a = 24.9765(10) A, has been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd3 at 21 °C. The crystal was prepared by flow method for 5 days using exchange solution in which mole ratio of CsOH and CsNO3 was 1 : 1 with total concentration of 0.05 M. The crystal was then dehydrated at 400 °C and 2 × 10-6 Torr for 2 days. The structure was refined to the final error indices, R1 = 0.051 and wR2 (based on F2) = 0.094 with 247 reflections for which Fo > 4σ (Fo). In this structure, about fifty-two Cs+ ions per unit cell are located at six different crystallographic sites with special selectivity; about one Cs+ ion is located at site I, at the centers of double oxygen-rings (D6Rs), two Cs+ ions are located at site I', and six Cs+ ions are found at site II'. This is contrary to common view that Cs+ ions cannot pass sodalite cavities nor D6Rs because six-ring entrances are too small. Ring-opening by the formation of ?OH groups and ring-flexing make Cs+ ions at sites I, I', and II' enter six-oxygen rings. The defects of zeolite frameworks also give enough mobility to Cs+ ions to enter sodalite cavities and D6Rs. Another six Cs+ ions are found at site II, thirty-six are located at site III, and one is located at site III' in the supercage, respectively. Forty Na+ ions per unit cell are located at two different crystallographic sites; about fourteen are located at site I, the centers of D6Rs and twenty-six are also located at site II in the supercage. Cs+ ions and Na+ ions at site II are recessed ca. 0.34(1) A and 1.91(1) A into the supercage, respectively. In this work, the highest exchange level of Cs+ ions per unit cell was achieved in zeolite X by conventional aqueous solution methods and it was also shown that Cs+ ion could pass through the sixoxygen rings.

• Journal of the Korean Chemical Society
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• v.37 no.6
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• pp.599-603
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• 1993

Crystal structure of bis(1,2-diaminopropane)palladium(II) bis(oxalato)palladate(II) has been determined by X-ray crystallography. Crystal data: $Pd_2C_{10}H_{10}N_{4}O_{8}$, $M_W$ = 573.09, orthorhombic, space group $P_{ccn}$ (No = 56), a = 16.178(5), b = 16.381(6), c = 6.685(2)$\{AA}$, V = 1771.6 $\{AA}^3$, $M_W$W = 573.09, $D_c$ = 2.014 g${\cdot}c\;m^{-3}$, Z = 4, T = 294K, F(000) = 1056.0 and $\mu$ = 20.466 c$m^{-1}$. The intensity data were collected with $Mo-K\alpha$ radiation (${\lambda}$ = 0.7107 $\AA)$ on an automatic four-circle diffractometer with a graphite monochromater. The structure was solved by Patterson method and refined by full matrix least-squares methods using Pivot weights. The final R and S values were R = 0.065, $R_W = 0.059, R_{all}$ = 0.065 and S = 4.315 for 605 observed reflections. Both cation and anion complexes are essentially planar and have dihedral angle of $18(l)^{\circ}$ between thier planes. In the crystal structure, they do not have the Magnus's salt type mixed stacks; instead, the complex anions form regular stacks along the c-axis with the M-M bond length of $3.343(5)\AA$ and their stacks are surrounded by the complex cations through hydrogen bonds with the nitrogen-oxygen distances of 2.94(3) and $3.31(4)\AA.$

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.85-85
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• 2011

화학적 혹은 생물학적인 방법으로 합성된 생분해성 고분자(biodegradable polymers)는 환경 문제와 인간의 생명 유지와 같은 인간 생활과 밀접한 관계가 있는 적용 분야로 인해 많은 관심을 받고 있으며, 국내 플라스틱의 폐기량만 해도 2003년을 기준으로 연간 4,000톤을 쉽게 넘고 있고 재활용되는 양은 전체의 1/3 수준이며, 나머지 2/3는 소각되거나 매립되고 있다. 폴리에스테르계 생분해성 섬유는 "미생물이 분비하는 효소로, 분해 가능한 화학합성 섬유"로서, 미생물이 분비하는 가수분해 효소에 의해 고분자 쇄가 절단, 저분자량 화합물이 돼 미생물의 체내로 흡수되며, 이것이 미생물의 체내에서 효소작용에 의해 산화탄소와 물로 분해되는 섬유로 정의된다. 생분해성 고분자 중 화학합성 고분자인 지방족 폴리에스테르계 생분해성 고분자는 특히 환경 산업으로부터 많은 관심을 받고 있으며, 이러한 결정성 폴리에스테르계 고분자의 물성은 고분자의 결정화도 뿐만 아니라, 압력, 온도 등에 의해서 변할 수 있는 결정 구조에 의해 크게 영향을 받는다. 생분해성 섬유는 실용화가 이미 시작됐고, 다용도화와 수요 확대를 위해 많은 연구소와 대학, 기업들이 연구개발을 진행하고 있으며, 향후 석유자원이 고갈된다는 것은 명백한 사실이므로 이에 따라 화석자원의 절약과 유효 이용을 위해서라도 바이오 베이스 폴리머를 주원료로 한생분해성 섬유의 개발은 매우 중요한 의미를 갖는다. 본 연구에서는 합성섬유 중에서 75%의 비중을 차지하는 폴리에스테르를 대체 가능한 고내열생분해성 폴리에스테르계 직물을 제조하여 범용 폴리에스테르와 염색온도에 대한 염색성을 고찰하였다. 염색온도($100^{\circ}C$, $110^{\circ}C$, $120^{\circ}C$, $130^{\circ}C$)별, 3종의 분산염료의 농도(0.25,0.5,1.0,2.0%o.w.f)별 Build-up성 및 균염성을 비교하였으며, 염색 시료의 견뢰도를 평가하였다.