• Korean Journal of Soil Science and Fertilizer
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• v.50 no.2
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• pp.93-99
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• 2017

Analysis of mineral nutrients in plant is required for evaluating diagnosis of plant nutritional status. Pretreatment procedure for the analysis of plant can be varied depending on elements to be analyzed. Wet-digestion is suitable for total nitrogen, phosphate and cations, however, digestion solution including nitric acid is not suitable for nitrogen analysis. Incineration procedure is required to analyze chloride, silicate and total sulfur. After digestion, total nitrogen is analyzed by Kjeldahl method, and phosphate is detected at 470nm by colorimetric analysis with ammonium meta vanadate. Cations and micro elements are determined by titration or colorimetry, also, these elements can be measured by Atomic absorption spectrometer (AAS) or Inductively coupled plasma spectrometer (ICP).

• Journal of Animal Science and Technology
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• v.58 no.5
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• pp.21.1-21.8
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• 2016

Background: The aim of the present study was to determine the effects of feeding trace mineralsfortified mixed microbial culture (TMC) on ruminal fermentation, nutrient digestibility, blood electrolyte status, nitrogen balance, and trace mineral balance in sheep. Methods: Mixed microbes [0.6 % (v/w) of Enterobacter sp., Bacillus sp., Lactobacillus sp., and Saccharomyces sp.] were cultured with 99 % feedstuffs and 0.4 % trace minerals including zinc and copper for ensiling. Six sheep (a mean body weight of $46.5{\pm}1.2kg$) were fed two diets: a control diet (concentrate mix and rye straw) and an experimental diet (a control diet + 3.1 % TMC). Results: TMC feeding did not induce negative effects on ruminal fermentation, nutrient digestibility, blood electrolytes, and nitrogen balance in sheep. Feeding with TMC increased the intake of trace minerals (p < 0.05) and did not affect absorption of trace minerals in the whole digestive tract. Feeding with TMC increased fecal excretion and absorbable intake, and retention of zinc and copper (p < 0.05) by 71 % and 77 %, respectively. Conclusion: Feeding with TMC resulted in higher zinc and copper bioavailability and retention without any adverse effects on sheep performance.

• Mycobiology
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• v.33 no.3
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• pp.147-149
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• 2005

The investigation was undertaken to enhance the decomposition process by pre-treatment of rice stubble, having higher concentration of lignin. Air-dried rice stubble was treated with 1.8 liter of 1% NaOH and autoclaved. Six cellulolytic fungi, Trichoderma harzianum, Penicillium citrinum, Curvularia lunata, Aspergillus flavus and Alternaria alternata were grown in basal synthetic medium along with delignified rice-residue as carbon source for production of soluble crude protein. Though the loss of cellulose has been observed by all of them but having a considerable status in the presence of T. harzianum and T. harzianum yielded highest percentage of crude protein (27.99%) with biomass of 375 mg, whereas the lowest protein value (17.91%) was recorded in case of A. niger with biomass of 422 mg. Among the imperfect fungi, T. harzianum was the most potent. Effects of incubation period and nitrogen sources on soluble crude protein production by T. harzianum were also undertaken in this study. Fifth day of incubation period and potassium nitrate as nitrogen source among other nitrogen sources was found most appropriate for soluble crude protein production by the mentioned organism.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.4
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• pp.582-587
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• 2007

The pale, soft, exudative (PSE) syndrome lowers storage quality and consumers acceptability in the particular meat. With the increase in the consumption of parted chickens in Korean meat consumption trade, a parallel increase in the concern over the PSE status of chickens have been noticed. The present study focused on the PSE status of broiler's breast to investigate the effects of different degrees of PSE on its quality and storage characteristics. A total of 46 broiler chickens of 35 days old averaging 1,251-1,350 g were selected for the study. Breast separated and skin was removed. The breast meat was stored at $4^{\circ}C$ for 3 days and were analysed for pH, lightness, yellowness, redness, shear force, water-holding capacity (WHC), cooking loss, Thiobarbituric acid reactive substances (TBARS) and Volatile basic nitrogen (VBN) on day 1 and 3 during the storage. Increase in the degree of broilers breast PSE during storage caused fall in pH and shear force and increase in lightness, cooking loss, TBARS, VBN. Broilers breast PSE status confirms the actual pale soft and exudative nature of meat.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.6
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• pp.828-836
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• 1996

The histological changes of gill, liver, spleen and muscle, and respiration and blood variables and liver glycogen content were examined in black seabream, Acanthopagrus schlegeli. Fish were exposed to a high level of total ammonia nitrogen (10.4 mg/l) and recovered from exposure $(0.4{\pm}0.2mg/l)$ in a closed recirculating seawater system. In the process of exposure, mortality was $9\%$, and hyperplasia, necrosis or inflammation appeared in all tissues except for muscle. Oxygen consumption was decreased by $49\%$, and red blood cell (RBC) number, hematocrit and hemoglobin concentration were significantly decreased, while plasma glucose contents, activities of glutamate-oxaloacetate transaminase (GOT) and glutamate-pyruvate transaminase (GPT) increased. Liver glycogen content significantly increased from $6.6\%\;to\;10.4\%$. A large amount of hemosiderin was observed in the splenic tissue. During the recovery period, RBC number, hematocrit, hemoglobin concentration, GOT and GPT activities were returned to the normal status. Histological status of liver tissue was returned to the normal, but liver glycogen content was not recovered. During the recovery period, spleen melanin-macrophages temporarily increased, but subsequently decreased to the normal status.

• 한국연소학회:학술대회논문집
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• 2003.05a
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• pp.295-300
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• 2003

In Korea, the emission standards for air pollutants will be more tighten from Jan. 2005. Especially, the new emission standards is focused on the nitrogen oxide. From this trend of standards, nitrogen oxide emission is hot issue in energy fields. Also, we have a new environmental problem, the carbon dioxide emission, which are related to the global warming. To solve the environmental problems, we must define the situation of clean-up technologies level in Korea and decide the direction of R&D for flue gas cleaning technologies. Now, this paper discus briefly on the De-NOx R&D activities and the large scale testing facility for flue gas clean-up technologies in Korea Institute of Energy Research. These discussions are contribute to the increasing of the R&D activities for flue gas clean-up technologies in Korea.

• Journal of the Korean Magnetic Resonance Society
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• v.23 no.3
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• pp.73-80
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• 2019

Nitrogen-vacancy (NV) is one of the most popular solid-state spin systems for quantum sensing. NV has been used for vector magnetometry with nanometer spatial resolution and sensors for nuclear magnetic resonance (NMR) in samples with small volume, less than 10 pL. Various studies are in progress to make NV a complementary sensor for current NMR technique. Fabricating and improving diamond itself are one of the research topics. This mini-review contains recent develops in diamond fabrication and treatment for higher NV yield. Additionally, we briefly introduce the development status of NV in NMR.

• Journal of Crop Science and Biotechnology
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• v.11 no.2
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• pp.141-150
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• 2008

The response of grain yield(GY) and milled-rice protein content(PC) to crop growth status and nitrogen(N) rates at panicle initiation stage(PIS) is critical information for prescribing topdress N rate at PIS(Npi) for target GY and PC. Three split-split-plot experiments including various N treatments and rice cultivars were conducted in Experimental Farm, Seoul National University, Korea in 2003-2005. Shoot N density(SND, g N in shoot $m^{-2}$) and canopy reflectance were measured before N application at PIS, and GY, PC, and SND were measured at harvest. Data from the first two years(2003-2004) were used for calibrating the predictive models for GY, PC, and SND accumulated from PIS to harvest using SND at PIS and Npi by multiple stepwise regression. After that the calibrated models were used for calculating N requirement at PIS for each of nine plots based on the target PC of 6.8% and the values of SND at PIS that was estimated by canopy reflectance method in the 2005 experiment. The result showed that SND at PIS in combination with Npi were successful to predict GY, PC, and SND from PIS to harvest in the calibration dataset with the coefficients of determination ($R^2$) of 0.87, 0.73, and 0.82 and the relative errors in prediction(REP, %) of 5.5, 4.3, and 21.1%, respectively. In general, the calibrated model equations showed a little lower performance in calculating GY, PC, and SND in the validation dataset(data from 2005) but REP ranging from 3.3% for PC and 13.9% for SND accumulated from PIS to harvest was acceptable. Nitrogen rate prescription treatment(PRT) for the target PC of 6.8% reduced the coefficient of variation in PC from 4.6% in the fixed rate treatment(FRT, 3.6g N $m^{-2}$) to 2.4% in PRT and the average PC of PRT was 6.78%, being very close to the target PC of 6.8%. In addition, PRT increased GY by 42.1 $gm^{-2}$ while Npi increased by 0.63 $gm^{-2}$ compared to the FRT, resulting in high agronomic N-use efficiency of 68.8 kg grain from additional kg N. The high agronomic N-use efficiency might have resulted from the higher response of grain yield to the applied N in the prescribed N rate treatment because N rate was prescribed based on the crop growth and N status of each plot.

• Journal of the Korean Society for Heat Treatment
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• v.2 no.2
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• pp.68-83
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• 1989

Physical metallurgy aspects of gaseous ferritic nitrocarburising are reviewed in the light of basic studies undertaken since 1975 which have illustrated inconsistencies between the iron-carbon-nitrogen ternary phase diagram at $570^{\circ}C$ and the experimental observation of the co-existence of the ${\varepsilon}$ carbonitride phase and ferrite. Thermodynamic investigations by Xu and Li together with those by Slycke et al are reviewed to illustrate compatability between a modified isothermal section of the Fe-C-N system and the formation and growth of a monophased ${\varepsilon}$ structure under a variety of processing conditions. The implications of the modified diagram in terms of innovations in industrial ferritic nitrocarburising practice are discussed, together with limitations on the control of the process. The importance of the developing technology of black nitrocarburising for enhanced wear, fatigue, and corrosion resistance is emphasised. Basic studies and industrial status of austenitic nitrocarburising treatments are also reviewed, which highlight the importance of substrate strengthening for high load bearing applications of anti-scuff thermochemical treatments.

• The Korean Journal of Ceramics
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• v.2 no.4
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• pp.177-180
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• 1996

Considerable progress in the development of CVD techniques for the deposition of diamond films has been achieved recently. Despite the polycrystalline structure of this material, its physical properties are now approaching those of natural type IIa diamond crystals. This paper will given some insight into the current status of CVD diamond thechnology with emphasis on optical and thermal applications. The role of process gas impurities like nitrogen will be discussed.