• Korean Journal of Mineralogy and Petrology
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• v.33 no.2
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• pp.115-127
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• 2020

The Unsang gold deposit has been one of the three largest deposits (Daeyudong and Kwangyang) in Korea. The deposit consists of Au-bearing quartz veins filling fractures along fault zones in Precambrian metasedimentary rock and Jurassic Porphyritic granite, which suggests that it might be an orogenic-type. Based on its mineral assemblages and quartz textures, quartz veins are classified into 1)galena-quartz, 2)pyrrhotite-quartz, 3)pyrite-quartz, 4)pegmatic quartz, 5)muscovite-quartz, and 6)simple quartz vein types. The pyrite-quartz vein type we studied shows the following alteration features: sericitization, chloritization, and silicification. The quartz vein contains minerals including white quartz, white mica, chlorite, pyrite, rutile, calcite, monazite, zircon, and apatite. Rutile with euhedral or medium aggregate occur at mafic part from laminated quartz vein. Two types of rutile are distinguishable in BSE image, light rutile is texturally later than dark rutile. Chemical composition of rutile has 89.69~98.71 wt.% (TiO₂), 0.25~7.04 wt.% (WO₃), 0.30~2.56 wt.% (FeO), 0.00~1.71 wt.% (Nb₂O₅), 0.17~0.35 wt.% (HfO₂), 0.00~0.30 wt.% (V₂O₃), 0.00~0.35 wt.% (Cr₂O₃) and 0.04~0.25 wt.% (Al₂O₃), and light rutile are higher WO₃, Nb₂O₅ and FeO compared to the dark rutile. It indicates that dark rutile and light rutile were formed at different stage. The substitution mechanisms of dark rutile and light rutile are suggested as followed : dark rutile [(V³⁺, Cr³⁺) + (Nb⁵⁺, Sb⁵⁺) ↔ 2Ti⁴⁺, 4Cr³⁺ (or 2W⁶⁺) ↔ 3Ti⁴⁺ (W⁶⁺ ↔ 2Cr³⁺), V⁴⁺ ↔ Ti⁴⁺], light rutile [2Fe³⁺ + W⁶⁺ ↔ 3Ti⁴⁺, 3Fe²⁺ + W⁶⁺ ↔ Ti⁴⁺ + (V³⁺, Al³⁺, Cr³⁺) +Nb⁵⁺], respectively. While the dark rutile was formed by cations including V³⁺, V⁴⁺, Cr³⁺, Nb⁵⁺, Sb⁵⁺ and W⁶⁺ by regional metamorphism of hostrock, the postdating light rutile was formed by redistribution of cations from predating dark rutile and addition of Fe²⁺ and W⁶⁺ from Au-bearing hydrothermal fluid during ductile shear.

• Journal of Korean Society of Forest Science
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• v.110 no.3
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• pp.393-405
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• 2021

With increasing anthropogenic emission sources, air pollutants are emerging as a severe environmental problem worldwide. Accordingly, the importance of landscape trees is emerging as a potential solution to reduce air pollutants, especially in urban areas. This study quantified and compared NO₂ and SO₂ reduction abilities of ten major landscape tree species and analyzed the relationship between reduction ability and physiological and morphological characteristics. The results showed NO₂ reduction per leaf area was greatest in Cornus officinalis (19.81 ± 3.84 ng cm^-2 hr^-1) and lowest in Pinus strobus (1.51 ± 0.81 ng cm^-2 hr^-1). In addition, NO₂ reduction by broadleaf species (14.72 ± 1.32 ng cm^-2 hr^-1) was 3.1-times greater than needleleaf species (4.68 ± 1.26 ng cm^-2hr^-1; P < 0.001). Further, SO₂ reduction per leaf area was greatest in Zelkova serrata (70.04 ± 7.74 ng cm^-2 hr^-1) and lowest in Pinus strobus (4.79 ± 1.02 ng cm^-2 hr^-1). Similarly, SO₂ reduction by broadleaf species (44.21 ± 5.01 ng cm^-2 hr^-1) was 3.9-times greater than needleleaf species (11.47 ± 3.03 ng cm^-2 hr^-1; P < 0.001). Correlation analysis revealed differences in NO₂ reduction was best explained by chlorophyll b content (R² = 0.671, P = 0.003) and SO₂ reduction was best described by SLA and length of margin per leaf area (R² = 0.456, P = 0.032 and R² = 0.437, P = 0.001, R² = 0.872, P < 0.001, respectively). In summary, the ability of trees to reduce air pollutants was related to photosynthesis, evapotranspiration, stomatal conductance, and leaf thickness. These findings highlight effective reduction of air pollutants by landscaping trees requires comprehensively analyzing physiological and morphological species characteristics.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.2
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• pp.125-140
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• 2022

The Xiquegou Pb-Zn deposit is located at the Qingchengzi orefield which is one of the largest Pb-Zn mineralized zone in the northeast of China. The geology of this deposit consists of Archean granulite, Paleoproterozoinc migmatitic granite, Paleo-Mesoproterozoic sodic granite, Paleoproterozoic Liaohe group, Mesozoic diorite and Mesozoic monzoritic granite. The Xiquegou deposit which is a Triassic magma-hydrothermal type deposit occurs as vein ore filled fractures along fault zone in unit 3 (dolomitic marble and schist) of Dashiqiao formation of the Paleoproterozoic Liaohe group. Xiquegou Pb-Zn deposit consists of quartz, apatite, calcite, pyrite, arsenopyrite, pyrrhotite, marcasite, sphalerite, chalcopyrite, stannite, galena, tetrahedrite, electrum, argentite, native silver and pyrargyrite. Wallrock alteration of this deposit contains silicification, pyritization, dolomitization, chloritization and sericitization. Based on mineral petrography and paragenesis, dolomites from this deposit are classified two type (1. dolomite (D₀) as wallrock, 2. dolomite (D₁) as wallrock alteration in Pb-Zn mineralization quartz vein ore). The structural formulars of dolomites are determined to be Ca_1.03-1.01Mg_0.95-0.83Fe_0.12-0.02Mn_0.02-0.00(CO₃)₂(D₀) and Ca_1.16-1.00Mg_0.79-0.44Fe_0.53-0.13Mn_0.03-0.00As_0.01-0.00(CO₃)₂(D₁), respectively. It means that dolomites from the Xiquegou deposit have higher content of trace elements compared to the theoretical composition of dolomite. The dolomite (D₁) from quartz vein ore has higher content of these trace elements (FeO, PbO, Sb₂O₅ and As₂O₅) than dolomite (D₀) from wallrock. Dolomites correspond to Ferroan dolomite (D₀), and ankerite and Ferroan dolomite (D₁), respectively. The structural formular of chlorite from quartz vein ore is (Mg_1.65-1.08Fe_2.94-2.50Mn_0.01-0.00Zn_0.01-0.00Ni_0.01-0.00Cr_0.02-0.00V_0.01-0.00Hf_0.01-0.00Pb_0.01-0.00Cu_0.01-0.00As_0.03-0.00Ca_0.02-0.01Al_1.68-1.61)_5.77-5.73(Si_2.84-2.76Al_1.24-1.16)_4.00O₁₀(OH)₈. It indicated that chlorite of quartz vein ore is similar with theoretical chlorite and corresponds to Fe-rich chlorite. Compositional variations in chlorite from quartz vein ore are caused by mainly octahedral Fe²⁺ <-> Mg²⁺ (Mn²⁺) substitution and partly phengitic or Tschermark substitution (Al^3+,VI+Al^3+,IV <-> (Fe²⁺ 또는 Mg²⁺)^VI+(Si⁴⁺)^IV).

• Journal of Aquaculture
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• v.2 no.2
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• pp.53-90
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• 1989

Feeding proper level of ration matchable with the appetite of fish will enhance production and also prevent waste of food and its consequence, side effects such as pollution of culture medium. To pursue this goal, elaborate studies on dissolved oxygen concentrations- as the major force in inducing appetite and the growth outcome are necessary. The growth of common carp of 67, 200, 400, 600, and 800 gram size groups was studied at oxygen concentrations ranging from 2.0 to 6 mg/$\iota$ in relation to rations from 1 to as many percent of the initial body weight as could be consumed under constant temperature of $25^{\circ}C$. The results from the experiments are summarized as followings; 1. Appetite: The smaller fish exhibited higher degree of appetite than the bigger ones at the same oxygen concentrations. The bigger the fish the less tolerant it was to the lower oxygen thersholds, and the degree of tolerence decreased as ration level increased. 2. Growth : Growth rate (percent per day) increased - unless consumption was suppressed by low oxygen levels- as the ration was increased to maximum. In case of 67 g fish, it reached the highest point of $5.05\%$ / day at $7\%$ ration under 5.0 mg/$\iota$ of oxygen. In case of 200 g fish, the maximum growth rate of $3.75\%$/day appeared at the maximum ration of $6\%$ under 5.5 mg/$\iota$ of oxygen. In 400 g fish, the highest growth of $3.37\%$/day occurred at the maximum ration of $5\%$ and 6.0 mg/$\iota$ of oxygen. In 600 g fish, the highest growth rate of $2.82\%$ /day was at the maximum ration of $4\%$ under 5.5 mg/$\iota$ oxygen. In case of 800g fish, the highest growth rate of $1.95\%$/day was at maximum tested ration of $3\%$ under 5.0 mg/$\iota$ oxygen. 3. Food Conversion Efficiency: Food conversion efficiency ($\%$ dry feed converted into the fish tissue) first increased as the ration was increased, reached maximum at certain food level, then started decreasing with further increase in the ration. The maximum conversion efficiency stood at higher feeding rate for the smaller fish than the larger ones. In case of 67 g fish, the maximum food conversion efficiency was at $4\%$ ration within 3.0-4.0 mg/$\iota$ oxygen. In 200g fish, the maximum efficiency was at $3\%$ ration within 4.0-4.5 mg/$\iota$ oxygen. In 400g fish, the maximum efficiency was at $2\%$ ration within 4.0 - 4.5 mg/$\iota$ oxygen. In 600 and 800g fish, the maximum conversion efficiency shifted to the lowest ration ($1\%$) and lower oxygen ranges. 4. Behaviour: The fish within uncomfortably low oxygen levels exhibited suppressed appetite and movements and were observed to pass feces quicker and in larger quantity than the ones in normal condition; in untolerably low oxygen the fish were lethargic, vomited, and had their normal skin color changed into pale yellow or grey patches. All these processes contributed to reducing food conversion efficiency. On the other hand, the fish within relatively higher oxygen concentrations exhibited higher degree of movement and their food conversion tended to be depressed when compared with sister groups under corresponding size and ration within relatively low oxyen level. 5. Suitability of Oxygen Ranges to Rations: The oxygen level of 2.0- 2.5 mg/$\iota$ was adequate to sustain appetite at $1\%$ ration in all size groups. As the ration was increased higher oxygen was required to sustain the fish appetite and metabolic activity, particularly in larger fish. In 67g fish, the $2\%$ ration was well supported by 2.0-2.5 mg/$\iota$ range; as the ration increased to $5\%$, higher range of 3.0-4.0 mg/$\iota$ brought better appetite and growth; from 5 till $7\%$ (the last tested ration for 67 g fish) oxygen levels over 4.0 mg/$\iota$ could sustain appetite. In 200 g fish, the 2 and $3\%$ rations brought the best growth and conversion rates at 3.5-4.5 mg/$\iota$ oxygen level; from 3 till $6\%$ (the last tested ration at 200 g fish) oxyge groups over 4.5 mg/$\iota$ were matchable with animal's appetite. In 400, 600, and 800 g fish, all the rations above $2\%$ had to be generally supported with oxygen levels above 4.5 mg/$\iota$.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.3
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• pp.274-279
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• 1983

In order to find out the application effect of commercial organic fertilizer on the germination rate of ginseng seed, growth of ginseng plant and changes of the physicochemical properties of soils, a Miwon organic fertilizer, byproduct of amino acid fermentation, was applied to the ginseng nursery bed. The application rates of Miwon organic fertilizer were 0kg-N from organic fertilizer and 30kg-N from wild grass compost per 10a as control(namely 0kg-N/10a), 2.5kg-N and 27.5kg-N/ 10a(2.5kg-N/10a) 5.0kg-N and 25kg-N/10a(5.0kg-N/10a), 10kg-N and 20kg-N/10a(10kg-N/10a), 15kg-N and 15kg-N/10a(15kg-N/10a) respectively, The obtained results are as follows: 1. The germination rate of ginseng seed were better in the plots that received 2.5kg, 5.0kg and 10kg-N/10a as compared with control plot. However no difference was found on germination rate between control and 15kg-N/10a, 2. The higher rate of missing plant was found in the 15kg-N/10a plot that showed poor growth. However control and 10kg-N/10a plot showed similar rate of missing plant. The best result, lower rate of missing plant, was obtained in the order of 5kg-N and 2.5kg-N/10a respectively. 3. The significant heavier ginseng root weight was obtained in 5kg-N/10a and 10kg-N/10a plot. However the root weight was decreased in the order of 2.5kg-N/10a, control, 15kg-N/10a. 4. In the physicochemical changes of soils between control and organic fertilizer treated soil before and after harvesting the increment of pH, C.E.C. and organic matter content along with the rate of organic fertilizer application were found. There were significant correlation between nitrate nitrogen and the rate of organic fertilizer application. 5. In the view points of germination rate, missing rate of plant and yield of ginseng root, it can be stated that the best result could be obtained from the plot that received 10kg-N/10a from Miwon commercial organic fertilizer and 10kg-N/10a from wild grass compost.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.5
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• pp.416-423
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• 1993

Fish sauces prepared from sardine, Sardinops melanosticta were tested for inhibitory activity against angiotensin-I converting enzyme(ACE). Three kinds of fish sauces were prepared from scrap(S), meat(M) and round(R) of sardine, respectively. ACE inhibitory activity of sardine sauce S and R decreased with the elapse of fermentation period, whereas that of sardine sauce M increased to 30 days and thereafter decreased. ACE inhibitory activity of sardine sauce M fermented with koji was higher than that without koji. And occurrence of $5\%$ TCA soluble peptide-nitrogen was similar to tendancy of the ACE inhibitory activity. The ACE inhibitory activity increased with an increment of amounts added and was stable at heat treatment in boiling water bath for 5hrs. $IC_{50}\%$ (Amounts of inhibitors need for $50\%$ inhibition) of the sardine sauce S, M and R fermented with(without) koji during 90 days was $125{\mu}g(140{\mu}g),\;200{\mu}g(100{\mu}g)$ and $125{\mu}g(135{\mu}g)$, respectively. From the profiles of fractionation of the sardine sauce R fermented without koji for 90 days, the molecular weight of most active fraction was about 1,400 and the amino acids of Glu, Ala, Leu and Lys were found in abundance.

• Korean journal of food and cookery science
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• v.1 no.1
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• pp.74-81
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• 1985

For this research, the Atka-fisher which are used commonly in many homes for baking and broilling were broiled by an iron baking method, a pan baking method, a grill baking method and a microwave baking method respectively after 20 hours salting with 3% salt concentration of fish muscle weight. This thesis has an intention of appreciating the tastes according to each baking method through a sensory test, of examining the corelation between the change of texture measured by Rheometer and a sensory test and of comparing the changes of chemical component of the fish. The results were as follow: 1. The appearance of the broiled Atka-fish maintained a good appearance by the iron baking method and the grill baking method. In the color, the iron baking method and the grill baking method by direct :fire resulted a good score too. In the flavor, there was a significant difference between the grill baking method and the microwave baking method while there was no difference between the iron baking method and the pan baking method. The result of tenderness showed that the pan baking method has the highest score. Difference between the iron baking method and the pan baking was not significant. There was no difference in tenderness between the grill baking method and the microwave baking method. The iron baking method showed-the highest score in juciness and the microwave baking method stowed the highest score in acceptability however the differences were not significant. 2. As a result of the measurement of the texture by Rheometer, the iron baking method and the grill baking method showed higher score than other methods in hardness and chewiness. In springiness and cohesiveness, there was no significant difference among methods. As a result of the measurement of the texture by Rheometer, the corelation with a sensory test was considered to be low. 3. After broil, the cooking retention was the highest in the pan baking method and the moisture content was the highest in microwave baking method. Nitrogen content was the highest in the iron baking method. Fat content was the highest in the iron baking method, followed by the grill baking method, the pan baking method, and the microwave baking method. Free amino acid content was the highest in the iron baking method, followed by the grill baking method, the pan baking method and the micro-wave baking method.

• Journal of Life Science
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• v.23 no.9
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• pp.1147-1154
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• 2013

This study was conducted to evaluate the antioxidation activity of Jeju crossbred horse (Jeju native horse ${\times}$ thoroughbred) leg bone extracts (HLBE) and its enzyme hydrolysates by determination of 1,1-diphenyl-2picryl-hydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzo thiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity, ferric reducing/antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC). HLBE was extracted with hot water for 24 hr and lyophilized. The lyophilized HLBE was hydrolyzed using multifect PR6L (MP), pepsin (PS), and a pepsin and pancreatin mixture (PSPC) for 4 hr at 60, 50, and $50^{\circ}C$, respectively. The hydrolysates were separated by a molecular weight of 3 kDa more or less. When the yield of HLBE was 100%, the yield of hydrolysates less than 3 kDa of MP, PS, and PSPC was 10.86, 3.26, and 8.00%, respectively. Enzyme hydrolysates with low molecular weight less than 3 kDa in MP and PSPC showed significantly higher DPPH, ABTS radical scavenging activity, and ORAC compared to HLBE and its hydrolysates with more than 3 kDa. However, the FRAP of the hydrolysates less than 3 kDa in PS was significantly higher than in MP. These results suggest that low molecular weight enzyme hydrolysates less than 3 kDa have more powerful antioxidation activity, especially when they are hydrolyzed by MP and PSPC rather than PS. Therefore, low molecular weight enzyme hydrolysates of HLBE hydrolyzed with MP and PSPC have significant potential as antioxidants in the food industry. Further in vivo studies are required to support the antioxidation activities of the hydrolysates in vitro.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.12
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• pp.1720-1725
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• 2011

Aspartic acid chelated iron (Asp-Fe) was synthesized by a new method using calcium carbonate, aspartic acid, and ferrous sulfate. This study was carried out to investigate the bioavailability of Asp-Fe in iron-deficient rats. We divided the rats into four experimental groups. The first was the normal diet control group, or NC. The second was the no treated control group of iron-deficient (ID) rats, or ID+C. The third was the heme-iron (heme-Fe) treated group of ID rats, ID+heme-Fe. And the fourth was the Asp-Fe treated group of ID rats, or ID+Asp-Fe. There were no differences among any of the experimental groups in diet consumption, change of body weight, or the weight of the livers, kidneys, or spleens. After 7 days of feeding, the iron content in the sera of the ID+Asp-Fe group (175.2 ${\mu}g$/dL) and the ID+heme-Fe group (140.8 ${\mu}g$/dL) were significantly higher than that of the ID-C group (96.1 ${\mu}g$/dL). The total iron binding capacity (TIBC) of the ID+Asp-Fe group (735.4 ${\mu}g$/dL) was significantly normalized compared to the ID+C group (841.9 ${\mu}g$/dL) or ID+heme-Fe group (824.6 ${\mu}g$/dL). The hematocrit level of the ID+Asp-Fe group was increased to normal levels, but there was no statistical difference among ID groups. The absorption ratio of heme-Fe was 21.3% and that of Asp-Fe was 50.2%, which indicates a 2.3 times higher ratio in comparison with heme iron. With the above results we found that Asp-Fe seems to be an efficient form of iron to supply iron deficient rats in order to cure them of anemia. Thus, these findings suggest that aspartic acid chelated iron has the potential to serve as a functional food related to iron metabolism.

• Korean Journal of Agricultural Science
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• v.18 no.1
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• pp.49-73
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• 1991

To elucidate enzymatic properties of $\alpha$-galactosidases (EC3, 2, 1, 22) from germinated soybean and Aspergillus niger changes in the enzyme activities and oligosaccharide contents during germination of soybean were determined and $\alpha$-galactosidases from germinated soybean and wheat bran culture of Aspergillus niger were purified by ammonium sulfate fractionation, ion exchange chromatography and gel filtration. Their chemical and enzymatic properties were investigated and the results obtained were summarized as follows : 1. $\alpha$-Galactosidase activity of soybean was maximized when it was germinated at $25^{\circ}C$ for 120 hours. And raffinose and stachyose in soybean were decomposed completely after 96 hours and 120 hours of germination, respectively. 2. The highest level of $\alpha$-Galactosidase activity was obtained when Aspergillus niger was grown on wheat bran medium at $30^{\circ}C$ for 96 hours. 3. Soybean $\alpha$-galactosidase was purified by 6.6 fold by ammonium slufate fractionation, ion exchange chromatography on DEAE-Cellulose and Sephadex A-50., and gel filtration on Sephadex G-150. Its specific activity was 825 units/mg protein and the yield was 2.5% of the total activity of crude extracts. 4. Aspergillus niger $\alpha$-galactosidase was purified by 23.7 fold. Its specific activity was 1,229 units/mg protein and the yield was 14% of the total activity of wheat bran culture. 5. The purified $\alpha$-galactosidases of soybean and Aspergillus niger were found to be homogeneous by polyacrylamide gel electrophoresis and by HPLC. 6. Chemical properties of the purified $\alpha$-galactosidases were : 1) The soybean $\alpha$-galactosidase was monomeric and its molecular weight was estimated to be 30,000 by SDS-PAGE whereas the Aspergillus niger $\alpha$-galactosidase was a tetrameric glycoprotein which consisted of identical subunits with molecular weight of 28,000 each.