• Title/Summary/Keyword: the year of chemistry

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Persulfate Wet Oxidation Method for the Determination of Total Phosphorus in Atmospheric Aerosols and Its Application for a Year-round Observation in Beijing

  • Okuda, Tomoaki;Gunji, Yuma;He, Kebin;Ma, Yongliang
    • Asian Journal of Atmospheric Environment
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    • v.7 no.3
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    • pp.169-175
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    • 2013
  • Measurement of the phosphorus concentration in aerosols in Beijing, which was a representative East Asian mega-city, was carried out. The optimum procedure for analyzing phosphorus in aerosols was found in this study. Recovery of phosphorus in environmental samples through the improved method was almost 100%. The concentration of phosphorus in TSP was $145{\pm}47\;ng/m^3$, with a seasonal variation showing high concentrations in winter and low concentrations in summer. The concentrations of phosphorus in $PM_{2.5}$ accounted for $35{\pm}6%$ of those in TSP, with no seasonal variations. The major source of phosphorus in aerosols in Beijing was soil dust, and additional sources of phosphorus in fine particles could be coal combustion and biomass burning.

SUPERCRITICAL WATER LOOP DESIGN FOR CORROSION AND WATER CHEMISTRY TESTS UNDER IRRADIATION

  • Ruzickova, Mariana;Hajek, Petr;Smida, Stepan;Vsolak, Rudolf;Petr, Jan;Kysela, Jan
    • Nuclear Engineering and Technology
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    • v.40 no.2
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    • pp.127-132
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    • 2008
  • An experimental loop operating with water at supercritical conditions(25MPa, $600^{\circ}C$ in the test section) is designed for operation in the research reactor LVR-15 in UJV Rez, Czech Republic. The loop should serve as an experimental facility for corrosion tests of materials for in-core as well as out-of-core structures, for testing and optimization of suitable water chemistry for a future HPLWR and for studies of radiolysis of water at supercritical conditions, which remains the domain where very few experimental data are available. At present, final necessary calculations(thermalhydraulic, neutronic, strength) are being performed on the irradiation channel, which is the most challenging part of the loop. The concept of the primary and auxiliary circuits has been completed. The design of the loop shall be finished in the course of the year 2007 to start the construction, out-of-pile testing to verify proper functioning of all systems and as such to be ready for in-pile tests by the end of the HPLWR Phase 2 European project by the end of 2009.

Startup Engineering Education Programs in Niigata University: How to Integrate Knowledge to Solve Engineering Problems

  • Yamagiwa, Kazuaki;Tanabe, Yuji;Harada, Shuji;Shimizu, Tadaaki;Oka, Tetsuo
    • Journal of Engineering Education Research
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    • v.15 no.5
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    • pp.8-13
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    • 2012
  • Faculty of engineering, Niigata University has been executing start-up engineering education programs for the first-year students to educate his or her ability to solve engineering problems. They are divided into teams and tackle a task that they expect to easily accomplish. The expected results are hardly obtained. Then they try to seek the gap between the results and their knowledge. They analyze the phenomena and improve the approach. They evaluate the results of second trial and the effectiveness of the measures. That is, the project requires so-called PDCA cycles for students to solve engineering problems. The start-up engineering project is one of the compulsory subjects and seven departments have given the students several tasks based on their technicality. The students exchange their knowledge, ideas and learn how to use knowledge to solve the problems. Their reports and questionnaire survey proved that the projects are highly effective to improve his or her ability to solve engineering problems and give them strong motivation to learn engineering. We introduce the some tasks and the outcomes of the projects set by seven departments; mechanical and production engineering, electrical and electronic engineering, information engineering, biocybernetics, chemistry and chemical engineering, civil engineering and architecture, and material science and engineering.

Preparation and Characteristics of Leather-like Material from Shark Intestines

  • Byun Hee-Guk;Je Jae-Young;Kim Se-Kwon
    • Fisheries and Aquatic Sciences
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    • v.5 no.2
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    • pp.136-140
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    • 2002
  • Every year fish skin, bone and intestines are discarded as processing waste material. The use of fish processing waste material is more economical and environmental-friendly. The leather-like material was produced using shark intestine. Physical charactistics such as tensile strength, elongation, tongue tearing strength, and bursting strength of the leather-like material were measured, and compared with those of a commercial leather product. The values of tensile strength, elongation, tongue tearing strength, and bursting strength of the leather-like material were $3.3kg/mm^2$, $53\%$, 13.0kg/mm and $18kg/cm^2$, respectively. Elongation $(l09\%)$ of the leather-like material coated with lacquer was higher than that of a commercial leather material, and the other factors were similar. The tensile strength and tongue tearing strength of the leather-like material was higher than those of shoes leather, but bursting strength was lower. These results suggested a potential value to use the leather-like material from shark intestines as a substitute for commercial leathers.

Ultrasonographic and Clinical Findings in Cats with Feline Lower Urinary Tract Disease

  • Seo, Seongeun;Na, Hyemin;Choi, Sooyoung;Choi, Hojung;Lee, Yungwon;Lee, Kija
    • Journal of Veterinary Clinics
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    • v.38 no.2
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    • pp.63-68
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    • 2021
  • Urethral obstruction is a life-threatening feline lower urinary tract disease (FLUTD). The rate of recurring urethral obstruction was 14.8-58.1% after the first occurrence. Ultrasonographic findings associated with reobstruction had been rarely reported although ultrasonography was a valuable technique for diagnosing urinary bladder calculi and distinguishing different FLUTD causes. This retrospective study aims to describe the ultrasonographic findings, urinalysis, and serum chemistry profile in cats with FLUTD and determine the associations of reobstruction with ultrasonographic findings, urinalysis, and serum chemistry profile. The present study included 141 cats that were followed up for more than 1 year. The ultrasonographic criteria included the presence of cystolithiasis, urine echogenicity, sediment, suspended linear strand, pericystic effusion, hyperechoic pericystic fat, ureteral dilation, pyelectasia, and perirenal effusion. The urinalysis criteria included hematuria, urine-specific gravity, pH, sediment, and proteinuria. The most common ultrasonographic findings in cats with FLUTD were echogenic urine and sediment. However, this study did not find an association between reobstruction and ultrasonographic findings, urinalysis, and serum chemistry profiles. Thus, an ultrasonographic examination may be insufficient to predict the risk of reobstruction although it is a useful modality for diagnosing FLUTD and making treatment direction.

Development of Methyl 2-aminobenzoate Reference Material in a Biocidal Product Matrix

  • So Yeon Lee;Kyungmin Kim;Junghyun Kim;Wooil Kim;Han Bin Oh
    • Mass Spectrometry Letters
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    • v.14 no.4
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    • pp.166-172
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    • 2023
  • The utilization of methyl 2-aminobenzoate as a biocide and pesticide has raised concerns regarding its potential toxicity. To assess its safety, it is crucial to determine its quantity and related toxicity using reference materials (RMs) or certified reference materials (CRMs). As an RM and CRM containing methyl 2-aminobenzoate within a biocidal product matrix is currently unavailable, this study aimed to produce a high-quality RM containing methyl 2-aminobenzoate, ensuring its homogeneity and stability, following the ISO Guide 35 and ISO 17034. The study determined that the produced RM exhibited homogeneity, as indicated by a calculated F-value (1.91) smaller than the critical F-value (3.02). In the assessment of isochronous short-term stability, the slope of the linear regression for the RM showed no statistically significant difference from zero when stored at temperatures of 4, 18, and 60 ℃ for 4 weeks. Regarding classical long-term stability, the RM demonstrated sustained stability over the course of one year when stored at 4 ℃. This study has successfully developed an RM for monitoring methyl 2-aminobenzoate in biocides and pesticides. Its quality underwent rigorous evaluation, confirming both homogeneity and stability.

Cholelithiasis and Choledolithiasis in a Dog (개의 담석증)

  • 윤정희;허진영;황국진;장동우;이영원;윤화영;권오경;최민철
    • Journal of Veterinary Clinics
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    • v.17 no.1
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    • pp.163-167
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    • 2000
  • Cholelithiasis and choledolithiasis were diagnosed with serum chemistry, abdominal radiography and ultrasonography in a 2.0 kg, 10 year-old Yorkshire Terrier dog showing signs of anorexia, vomiting, iceterus and depression. In serum chemistry, the level of alanine transferase, alkaline phosphatase, aspartate transferase, total bilitrubin and direct bilirubin were elevated. On abdominal radiographs, focal lesions with increased radiopacity were seen in the hepatic region and the size of liver was increased. In ultrasonographic examination, it were seen that distension of gall bladder, hypercehoic change of liver, obstruction of cystic duct by calcult and calculi in the gall bladder. Cholecystectomy was undertaken and there were no complications after the operation.

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Determination of Springwater Characteristics by Measurement of Tritium in Water (삼중수소 측정에 의한 약수터 물의 수질특성 연구)

  • Kim, Jong Hun;Choi, Yong Wook;Chung, Taek Kyun
    • Journal of the Korean Chemical Society
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    • v.40 no.6
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    • pp.436-444
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    • 1996
  • The characteristics of water have been studied for 1 year by means of relationships between tritium and total dissolved solid(TDS), tritium and conductivity, tritium and chloride, and tritium and total hardness for 15 springs in the vicinity of Jeonju city of Korea. From the results of the study, the springs were divided into four characteristic groups, but the characteristics of most springwaters studied were similar to those of rainfall. Fifteen springwaters were evaluated to see if those are tasty and healthy using the Hashimoto's Mineral Balance Index. As a result, only one spring (J-4) was found as tasty and healthy.

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Hepatic Encephalopathy in a Dog (개의 간성 뇌증)

  • 반현정;황철용;김종민;윤화영;윤정희;오태호;한홍율
    • Journal of Veterinary Clinics
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    • v.18 no.3
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    • pp.293-296
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    • 2001
  • Hepatic encephalophthy was diagnosed with serum chemistry, abdominal radiography and ultrasonography in a 2.6kg, 4 year-old maltese dog showing signs of hypersalivation, involutary spasm of facial muscles, ataxia, behavior abnormalities like dullness, sleep disorder, restlessness. In serum chemistry, the level of alanine transferase and aspartate trasferase was mildly elevated, ammonia was severely increased. On abdominal radio-graphs, the size of liver was mildly decreased. In ultrasonographic examination, diffuse lesion with hyperechoic change and decreased vasculature were seen in the hepatic region. But vascular abnormalities of liver were not observed. Drug and dietary therapy were undertaken and severities of clinical sign were alleviated.

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Log Cultivation of the Birch Fungus Piptoporus betulinus using Betula davurica (물박달나무를 이용한 자작나무버섯의 원목재배)

  • Ka, Kang-Hyeon;Ryu, Sung-Ryul;Lee, Bong-Hun;Yoon, Kab-Hee;Bak, Won-Chull
    • The Korean Journal of Mycology
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    • v.36 no.1
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    • pp.98-100
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    • 2008
  • A birch fungus, Piptoporus betulinus, is judged the mushroom with economical value that produces the fruiting body on Betula trees, but the mushroom rarely occurs in Korean birch forest. So, the fungus was applied to log cultivation for the production of fruiting body on Betula davurica. The fungus produce the fruiting bodies in the early August of the next year after inoculation in April and its mushroom matured in October. The mushroom produced 212 g to 1,298 g fresh weight in one or two mushrooms per a log. Thus, it is considered that log cultivation of the fungus has a potential to mass production of fruiting body and is expected to introduce to more researches to develop the use of this mushroom.