• Title/Summary/Keyword: Basic and Analytical Science

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Studies on the Separation and Preconcentration of Metal Ions by XAD-16-[4-(2-thiazolylazo)] orcinol Chelating Resin (XAD-16-[4-(2-thiazolylazo)]orcinol 킬레이트 수지에 의한 금속이온의 분리 및 농축에 관한 연구)

  • Lee, Won;Seol, Kyung-Mi;An, Hye-Sook;Lee, Chang-Heon;Lim, Jae-Hee
    • Analytical Science and Technology
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    • v.10 no.4
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    • pp.282-290
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    • 1997
  • The sorption and desorption properties of U(VI), Th(IV), Zr(IV), Cu(II), Pb(II), Ni(II), Zn(II), Cd(II) and Mn(II) ions on XAD-16-[4-(2-thiazolylazo)orcinol] (TAO) chelating resin were studied by elution method. The effect was examined with respect to overall capacity of each metal ion, separation of mixed metal ions, flow rate and concentration of buffer solution for optimum condition of sorption. The overall capacities of some metal ions on this chelating resin were 0.35nmol U(VI)/g resin, 0.49nmol Th(IV)/g resin, 0.41nmol Cu(II)/g resin, and 0.31nmol Zr(IV)/g resin, respectively. The elution order of metal ions obtained from breakthrough capacity and overall capacity at pH 5.0 was Th(IV)>Cu(II)>U(VI)>Zr(IV)>Pb(II)>Ni(II)>Zn(II)>Mn(II)>Cd(II). The group separation of mixed metal ions was possible by increasing pH in pH range 2~5 at a flow rate of 0.28mL/min. Characteristics of desorption were investigated with desorption agents such as $HNO_3$, HCl, $HClO_4$, $H_2SO_4$, and $Na_2CO_3$. It was found that 2M $HNO_3$ showed high desorption efficiency to most of metal ions except Zr(IV) ion. Also, desorption and recovery of Zr(IV) ion were successfully performed with 1M $H_2SO_4$. Recovery of trace amount of U(VI) ion from artificial sea water was over 94%. The chelating resin, XAD-16-TAO was successfully applied to group separation of rare earth metal ions from U(VI) by using 2M $HNO_3$ as an eluent.

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Comparison of isoButoxycarbonyl derivatives, tert.-butyldimethylsilyl derivatives, with US EPA Method in the sensitivity of Alkylphenols, Chlorophenols, and Bisphenol A Potential field-screening applications of GC/MS-SIM (기체 크로마토그래피/질량분석기를 이용한 field-screening 적용을 위한 알킬페놀류, 클로로페놀류 및 비스페놀 A의 isoBOC 유도체, TBDMS 유도체와 US EPA 방법의 비교)

  • Kim, Hyub;Hong, Jong-Ki;Kim, Yong-Hwa;Kim, Kyoung-Rae
    • Analytical Science and Technology
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    • v.15 no.3
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    • pp.196-213
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    • 2002
  • The alkylphenols, chlorophenols and bisphenol A were determined by gas chromatography/mass spectrometry-selected ion monitoring mode followed by three work-up methods for comparison; EPA method, isoBOC derivatization method and TBDMS derivatization method. Eleven phenols in water samples were extracted with dichloromethane. Also, solid-phase extraction (SPE) with XAD-4 and subsequent conversion to isobutoxycarbonyl derivatives or tert.-butyldimethylsilyl derivatives for sensitive analysis with the selected ion-monitoring (SIM) mode. The recoveries were 85.1~109.9% (EPA method) and 90.3~126.6% (isoBOC derivatization and TBDMS derivatization), respectively. The method detection limit of bisphenol A for SIM were 0.732 ${\mu}g/{\ell}$ (EPA method), 0.002 ${\mu}g/{\ell}$ (isoBOC derivatization) and 0.021 ${\mu}g/{\ell}$ (TBDMS derivatization). The SIM responses were linear with the correlation coefficient varying 0.9755~0.9981 (isoBOC derivatization), and 0.9908~0.9996 (TBDMS derivatization). When these methods were applied to treated wastewater sample from a polyethylene plant, the concentrations of 11 phenols were below the method detection limit.

The Optimum Conditions for the Simultaneous Determination of Neurotransmitters in Rat Brain Striatum by High Performance Liquid Chromatography with Electrochemical Detection (HPLC-ECD를 이용한 흰쥐 뇌의 선조체 중 신경전달물질의 동시분석시 최적 조건)

  • Kang, Jong-Seong;Mun, Min-Seon;Shin, Hyung-Seon;Lee, Soon-Chul
    • Analytical Science and Technology
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    • v.8 no.2
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    • pp.215-220
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    • 1995
  • A simple, efficient and sensitive method was described for the simultaneous determination of catecholamine, indoleamine and related metabolites from the homogenates of the rat brain striatum by HPLC-ECD. The optimum mobile phase on a reverse phase $C_{18}$ column was 35mM sodium acetate buffer(included 10mM citric acid, 0.13mM $Na_4EDTA$, 0.58mM SOS, pH3-4):MeOH=85:15. The column temperature was $30^{\circ}C$. Dopamine(DA), 3, 4-dihydroxyphenyl acetic acid(DOPAC), homovanilic acid(HVA), 5-hydroxyindole acetic acid(5-HIAA), serotonin(5-HT) and noradrenaline(NA) could be separated and analysed to very small amount. The detection limits of this method were 2~10pg per injection for all components. The effects of age and sex of rat on the contents of the catecholamines and their metabolites in rat brain striatum were studied. The levels of DA and 5-HT contents of the 7 week old female rats were higher than those of the 7 week old male rats. As the age of rat increases, the contents of DOPAC increased significantly.

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Problems of Applying Information Technologies in Public Governance

  • Goshovska, Valentyna;Danylenko, Lydiia;Hachkov, Andrii;Paladiiichuk, Sergii;Dzeha, Volodymyr
    • International Journal of Computer Science & Network Security
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    • v.21 no.8
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    • pp.71-78
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    • 2021
  • The relevance of research provides the necessity to identify the basic problems in the public governance sphere and information technology relations, forasmuch as understanding such interconnections can indicate the consequences of the development and spreading information technologies. The purpose of the research is to outline the issues of applying information technologies in public governance sphere. 500 civil servants took part in the survey (Ukraine). A two-stage study was conducted in order to obtain practical results of the research. The first stage involved collecting and analyzing the responses of civil servants on the Mentimeter online platform. In the second stage, the administrator used the SWOT-analysis system. The tendencies in using information technologies have been determined as follows: the institutional support development; creation of analytical portals for ensuring public control; level of accountability, transparency, activity of civil servants; implementation of e-government projects; changing the philosophy of electronic services development. Considering the threats and risks to the public governance system in the context of applying information technologies, the following aspects generated by societal requirements have been identified, namely: creation of the digital bureaucracy system; preservation of information and digital inequality; insufficient level of knowledge and skills in the field of digital technologies, reducing the publicity of the state and municipal governance system. Weaknesses of modern public governance in the context of IT implementation have been highlighted, namely: "digitization for digitalization"; lack of necessary legal regulation; inefficiency of electronic document management (issues caused by the imperfection of the interface of reporting interactive forms, frequent changes in the composition of indicators in reporting forms, the desire of higher authorities to solve the problem of their introduction); lack of data analysis infrastructure (due to imperfections in the organization of interaction between departments and poor capacity of information resources; lack of analytical databases), lack of necessary digital competencies for civil servants. Based on the results of SWOT-analysis, the strengths have been identified as follows: (possibility of continuous communication; constant self-learning); weaknesses (age restrictions for civil servants; insufficient acquisition of knowledge); threats (system errors in the provision of services through automation); opportunities for the introduction of IT in the public governance system (broad global trends; facilitation of the document management system). The practical significance of the research lies in providing recommendations for eliminating the problems of IT implementation in the public governance sphere outlined by civil servants..

An Analytical Study on the Factors of Job Changes at Public Libraries according to Their Changing Surrounding Environments (주변 환경 변화에 따른 공공도서관의 직무 변화 요인 분석 연구)

  • Park, Hyun-Woo;Cho, Hyun-Yang
    • Journal of Korean Library and Information Science Society
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    • v.51 no.2
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    • pp.23-53
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    • 2020
  • Following the rapid development and change of information technologies and sociocultural environments, public libraries are recently facing demand for various changes regarding their traditional functions and roles. They need to make efforts to understand accurately the changing factors of their surrounding environments and their resulting job changes so that they can make active responses to the changes of the times. The purposes of this study are to diagnose changing situations in the current surrounding environments and job content of public libraries and propose a basic direction for them to figure out and react to the causes of their core change content. For these purposes, the study 1) examined literature and previous studies on the surrounding environments and job factors of public libraries, 2) reviewed current job states and change cases in major criteria and standards, legislations, institutions, and policies about public libraries, and finally 3) identified the factors of their surrounding environments and job changes, tested their validity in the delphi method.

Ribose-induced Maillard Reaction as an Analytical Method for Detection of Adulteration and Differentiation of Chilled and Frozen-thawed Minced Veal

  • Akbarabadi, Masoumeh;Mohsenzadeh, Mohammad;Housaindokht, Mohammad-Reza
    • Food Science of Animal Resources
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    • v.40 no.3
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    • pp.350-361
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    • 2020
  • Quality control of meat products is one of the main concerns of consumers, governmental control authorities, and retailers. The purpose of this study was to employ ribose-induced Maillard reaction in detection of meat adulteration and differentiation of fresh-chilled from frozen-thawed minced veal. The browning intensity was assessed through measuring the absorbance at 420 nm with a spectrophotometer as well as the direct analysis of the color and pH. The results showed that CIE b*, CIE a*, and A420* values in the extract of fresh-chilled veal were significantly (p<0.05) higher than frozen-thawed samples. The extract of frozen meat samples stored at -18℃ became significantly darker and more yellowish compared to -4℃. The results showed that the A420* value in the frozen-thawed veal stored at -4℃ and -18℃ was reduced by approximately 17.22±3.53% and 11.68±2.49%, respectively, compared with fresh-chilled veal. The findings also showed that the storage temperature of minced veal and the heating time in this reaction had a significant effect on all tested variables (p<0.0001). The proposed method can be considered as an easy, quick, and inexpensive test for differentiating between the fresh-chilled and frozen-thawed minced veal.

A Study on the Durability of Manure Composting Facilities (축분 퇴비화 시설 내구성에 관한 조사연구)

  • Hong, Ji-Hyung
    • Journal of Animal Environmental Science
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    • v.16 no.1
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    • pp.13-20
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    • 2010
  • Manure compost is a main product from animal wastes in Korea. Solid manure is usually treated by aerobic composting at manure composting facilities for land reinforcement. Agricultural use of manure compost as organic fertilizer resources, mainly manure compost, is now recommended in Korea. This study investigated the evaluation of durability about the manure composting machinery and structures which was controlled by aeration and periodic agitating. The questionnaire addressed three main topics as follows: operating practices, machinery and maintenance of the manure composting facilities are being operated. A total of the 22 manure composting facilities in an agricultural cooperative were surveyed. The results obtained in this survey were summarized as follow: The major causes of manure composting apparatus trouble were corrosion and wear, overloading and foreign matter etc. The highly trouble frequency of the agitator, packer and conveyor were chain, agitating blade and shaft, motor and screw vane, respectively. These analytical results can be used as basic information to establish the maintenance control methods and durability standard of manure composting facility.

Recommendation of P and K Fertilizers for Crops Based on Soil Testing (토양분석치(土壤分析値)에 의(依)한 작물별(作物別) 인산(燐酸) 및 가리시비량(加里施肥量) 결정법(決定法))

  • Hong, Chong Woon;Kim, Yung Sup;Kim, Yung Koo
    • Korean Journal of Soil Science and Fertilizer
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    • v.6 no.1
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    • pp.29-31
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    • 1973
  • Upon the assumption that the available components in the soil evaluated by present analytical procedures, are as effective as the components applied to the soil as fertilizer, some formulas for the calculation of fertilizer requirements (F. R) for crops are suggested. Basically, the formulas are derived by combining the country average values of soil test data(${\overline{ST}}$) and of the optimum rate of fertilizers (ORF) for crops obtained from N.P.K. trials in farmer's field, as following. $$F.R(kg/10a)={\overline{ST}}(kg/10a)+ORFkg/10a-ST(kg/10a)$$ where, ST denotes the available components tested in the soil under question. Although this formula can be used both for P and K fertilizers, considering the significance of the potassium saturation rate of the soil for the availability of K, for the calculation of K fertilizer requirement, following formula is suggested. $$F.R(kg/10a)=(C.E.C.{\times}B.S.R.K.-KST(me/100g){\times}CF$$ where, B. S. R. K. is the basic potassium saturation rate of the soil and CF is conversion factor for the conversion of K me/100g into $K_2O$ kg/10a. The B. S. R. K. for different crops are obtained from the country average values of soil exchangeable K (${\overline{KST}}$), cation exchange capacity (CEC) and the optimum rates of K fertilizers for crops (ORF $K_2O$). $$B.S.R.K.=\frac{{\overline{KST}}{\times}CF+ORF(K_2O)}{CEC{\times}CF}$$ Using these formulas, equations for P and K fertilizer requirements for rice, barley, wheat, corn, italian millet, soy bean, sweet potato, potato and rape are derived.

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Analytical Study on the Relationship between Centralities of Research Networks and Research Performances (연구자 네트워크의 중심성과 연구성과의 연관성 분석 - 국내 기록관리학 분야 학술논문을 중심으로 -)

  • Lee, Soo-Sang
    • Journal of Korean Library and Information Science Society
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    • v.44 no.3
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    • pp.405-428
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    • 2013
  • This study tried to explore the relation between research networks(coauthor network, author co-citation network, author bibliographic coupling network) and research performance of Records and Archives Management study in Korea. For the analysis, three basic types of network centrality and three indicators of research performance are used. The summary of this study is as follows: Firstly, there are relations between three centralities and three indicators of research performance in the coauthor network. Secondly, there are relations between betweenness centrality and research performance in the author co-citation/author bibliographic coupling networks. Thirdly, there are relations between three centralities in the each research network. Fourthly, there are not high relations between all centralities of the three research networks.

Effects of Adulterants in HCl on Artificial Hatching in the Silkworm Eggs (염산의 협잡물이 잠종의 인공부화에 미치는 영향)

  • 김윤식;김락상
    • 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.

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