• Title/Summary/Keyword: Consecutive process

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Implementation of magnetic Fe3O4@ZIF-8 nanocomposite to activate sodium percarbonate for highly effective degradation of organic compound in aqueous solution

  • Sajjadi, Saeed;Khataee, Alireza;Soltani, Reza Darvishi Cheshmeh;Bagheri, Nafiseh;Karimi, Afzal;Azar, Amirali Ebadi Fard
    • Journal of Industrial and Engineering Chemistry
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    • v.68
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    • pp.406-415
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    • 2018
  • Here, as-synthesized $Fe_3O_4$ nanoparticles were incorporated into the zeolitic imidazolate framework (ZIF-8) lattice to activate sodium percarbonate (SPC) for degradation of methylene blue (MB). The reaction rate constant of $Fe_3O_4@ZIF-8/SPC$ process ($0.0632min^{-1}$) at acidic conditions (pH = 3) was more than six times that of the $Fe_3O_4/SPC$ system ($0.009min^{-1}$). Decreasing the solute concentration, along with increasing SPC concentration and $Fe_3O_4@ZIF-8$ nanocomposite (NC) dosage, favored the catalytic degradation of MB. The $Fe_3O_4@ZIF-8$ NC after fifteen consecutive treatment processes showed the excellent stability with a negligible drop in the efficiency of the system (<10%). The reaction pathway was obtained via GC-MS analysis.

Plan for the Development of a Standardized Dummy for Persons in Need of Rescue in a Confined Space (밀폐공간 구조 요구자를 위한 더미 표준화 개발 방안)

  • Choi, Seo-Yeon;Rie, Dong-Ho;Kim, Hyung-Jun
    • Journal of the Korea Safety Management & Science
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    • v.18 no.4
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    • pp.99-105
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    • 2016
  • This study was conducted to develop a dummy in an environment similar to the human body, to prepare a standard for evaluation and to present the process of the production in order to evaluate the performance of the robot that can detect the persons needing rescue in a confined space, who are difficult for fire-fighting officials to rescue in case of fire and disaster. As a result, a standard for evaluation was developed and standardized into four parts 'Normal,' 'Risk Stage 1,' 'Risk Stage 2' and 'Risk Stage 3'based on the number of breath cycles, carbon dioxide concentration, core temperature and criteria for hearing to recognize the voice. In addition, in order to produce a dummy, fever, breathing capacity and voice output function were compared and analyzed. This study has significance that it built up basic data of the method of producing the actual dummy, by presenting characteristics and controlling methods using the waterproof insulation heating coil for the function, solenoid valve for the consecutive output of breathing capacity and USB program sound board for voice output.

Catalytic Pyrolysis of Various Carbon Number Feed Oil Using a Spouted Bed Reactor (Spouted Bed Reactor를 이용한 다양한 탄소수 원료유 촉매 열분해)

  • Yoo, Kyeong Seun;Park, Sung Hoon;Park, Young-Kwon
    • Applied Chemistry for Engineering
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    • v.22 no.6
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    • pp.627-630
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    • 2011
  • We focus on a catalytic process based on direct injection method that can produce high-quality oils of gasoline and kerosene with various carbon-number feed oils. The reaction characteristics of a commercial catalyst were analyzed using a spouted bed reactor. Decane and pentadecane were used to compare the characteristics of the fixed bed and the spouted bed reactor. The yield of gasoline plus kerosene was highest at the reaction temperature of $550^{\circ}C$. For the spouted bed reactor, the at-a-pulse injection was more effective for catalytic cracking of feed oils than multiple consecutive injections. The reaction activity became higher as the carbon number of feed oil is larger.

Fractional radioactive decay law and Bateman equations

  • Cruz-Lopez, C.A.;Espinosa-Paredes, G.
    • Nuclear Engineering and Technology
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    • v.54 no.1
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    • pp.275-282
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    • 2022
  • The aim of this work is to develop the fractional Bateman equations, which can model memory effects in successive isotopes transformations. Such memory effects have been previously reported in the alpha decay, which exhibits a non-Markovian behavior. Since there are radioactive decay series with consecutive alpha decays, it is convenient to include the mentioned memory effects, developing the fractional Bateman Equations, which can reproduce the standard ones when the fractional order is equal to one. The proposed fractional model preserves the mathematical shape and the symmetry of the standard equations, being the only difference the presence of the Mittag-Leffler function, instead of the exponential one. This last is a very important result, because allows the implementation of the proposed fractional model in burnup and activation codes in a straightforward way. Numerical experiments show that the proposed equations predict high decay rates for small time values, in comparison with the standard equations, which have high decay rates for large times. This work represents a novelty approach to the theory of successive transformations, and opens the possibility to study properties of the Bateman equation from a fractional approach.

Protective Effect of Atractylodes macrocephala and Taraxacum spp. Combination Treatment in Balb/c Mice with Dextran Sulfate Sodium-Induced Ulcerative Colitis

  • Lee, Donghun;Kim, Hocheol
    • The Korea Journal of Herbology
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    • v.32 no.3
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    • pp.79-87
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    • 2017
  • Objectives : This study aimed to investigate the protective effects of an herbal mixture of Atractylodes macrocephala and Taraxacum spp. (ATC) on ulcerative colitis. We have previously screened traditional medicinal herbs to discover the effective candidate by the animal model. A. macrocephala and T. spp were identified as one of the effective herbs in the screening process. Methods : Experimental colitis was induced in male Balb/c mice by administering drinking water containing dextran sulfate sodium, which mimics the clinical and histological features of ulcerative colitis in human. ATC at doses of 30, 100 or 300 mg/kg were orally administered to mice twice per day for 10 consecutive days. To evaluate the damage from experimentla ulcerative colitis, body weight, colon length, disease activity index, myeloperoxidase and histological changes were measured and analyzed. Results : The administration of dextran sulfate sodium with drinking water resulted in markedly reduced colon length, severe body weight loss, increased levels of myeloperoxidase activity and histological damages in mice. ATC treatment significantly ameliorated the colon shortening, histological damage, body weight loss and disease activity index score in a dose-dependent manner. ATC also attenuated the colonic myeloperoxidase activity which reflects the severity and extent of inflammatory damage of colon. Conclusions : ATC exerts protective effects against inflammatory colonic structural damage induced by epithelial barrier integrity impairment. ATC also inhibits weight loss and related symptoms of UC which can be considered as the functional recovery of colon.

A QUANTITATIVE APPROACH FOR ASSESSING THE OVERSEAS BUSINESS CAPABILITIES OF CONSTRUCTION FIRMS

  • Hae Beom Yang;Woosik Jang;Kang-Wook Lee;Heedae Park;Seung Heon. Han;Hyun-woo You
    • International conference on construction engineering and project management
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    • 2013.01a
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    • pp.308-314
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    • 2013
  • Although global construction spending has experienced slow growth due to consecutive economic crises, global contractors have consistently attempted to expand their overseas market share, leading to more intense competition among contractors in the international construction market. In this market environment, owners, clients and financial institutions require reasonable and systematic criteria to effectively assess the business capabilities of international construction firms. However, the existing evaluation methods for construction firms rarely consider overseas-focused business capabilities. To address this problem, this study proposes a quantitative approach to assessing the overseas business capabilities of international construction firms. The limitations of existing approaches are reviewed, and the capabilities required to perform overseas businesses are analyzed through expert interviews. Finally, 18 evaluation indices are suggested in four categories: technology resources, project management, experience and performance, and sustainability. The relative weight of each index is determined according to the Analytical Hierarchy Process (AHP) method, and a preliminary investigation of 11 Korean construction firms is conducted. The proposed method is expected that it will provide the rational criteria for international owners, clients, and financial institutions for decision-making and for evaluating international contractors.

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Chlorphenesin Galactoside Production using Immobilized β-galactosidase-producing Escherichia coli (고정화된 β-galactosidase 생산 대장균을 이용한 chlorphenesin galactoside 생산)

  • Jung, Kyung-Hwan
    • Journal of Life Science
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    • v.25 no.10
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    • pp.1164-1168
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    • 2015
  • Previous research showed that chlorphenesin galactoside (CPN-Gal), a preservative in cosmetics, was safer than CPN against human skin cells [9]. To establish a stable and long-term process for CPN-Gal production, we investigated the repeated-batch process. In this process, β-gal-producing recombinant Escherichia coli cells were immobilized in calcium alginate beads, and CPN was converted to CPN-Gal by the transgalactosylation reaction. The process was conducted in a 300 ml flask, which contained E. coli cell-immobilized alginate beads, 33.8 mM of CPN, and 400 g/l of lactose. The pH and temperature were 7.0 and 40℃, respectively. During the repeated-batch operation, four consecutive batch operations were conducted successfully until 192 hr. The conversion yield of CPN to CPN-Gal was 64% during 192 hr, which was higher than the values in previous reports [3, 13]. Thereafter, however, the conversion yield gradually decreased until the operation was finished at 336 hr. Western blotting of immobilized E. coli cells revealed that β-gal gradually decreased after 192 hr. In addition, alginate beads were cracked when the operation was finished. It is probable that, including this loss of E. coli cells by cracks, deactivation, and product inhibition of E. coli β-gal might lead to a gradual decrease in the production of CPN-Gal after 192 hr. However, as the purification of β-gal is not necessary with β-gal-producing recombinant E. coli cells, β-gal-producing E. coli cells might be a practical and cost-effective approach for enzymatically synthesizing CPN-Gal. It is expected that this process will be extended to long-term production process of CPN-Gal for commercialization.

Two-step High Temperature Pretreatment Process for Bioethanol Production from Rape Stems (유채대의 이단 고온 처리에 의한 알콜 발효용 당화물 생산)

  • Han, Jae-Gun;Oh, Sung-Ho;Jeong, Myoung-Hoon;Kim, Seung-Seop;Seo, Hyeon-Beom;Jeong, Kyung-Hwan;Jang, Young-Seok;Kim, Il-Cheol;Lee, Hyeon-Yong
    • KSBB Journal
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    • v.24 no.5
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    • pp.489-494
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    • 2009
  • Two-step pretreatment process was investigated to efficiently hydrolyzed rape stems for obtaining fermentable sugars. The process was consisted of two consecutive steps as $200^{\circ}C$ and 15 MPa and $374^{\circ}C$ and 24 MPa with the flow rate of 5 mL/min. Under this condition, 5.5 (g/L) of glucose and 25.6 (g/L) of xylose were obtained from rape stems, showing 18% of glucose yield based on 25% cellulose in the rape stems. It was also found that this process could generate less amounts of toxic residues, such as HMF (Hydroxy- Methyl-Furfural) and other fulfural components during hydrolysis process. It could reaction maintain relatively high ethanol production yield as 90% of theoretical conversion yield from glucose. Therefore, this pretreatment process could be applied to hydrolyze other cellulosic and marine resources such as woods, stem and algae for bioethanol production.

Development of $O_2$ Purifier by Pressure Swing Adsorption Process (고순도 산소 생산을 위한 산소 정제 PSA 공정 개발)

  • Lee Chang-Ha;Jee Jeong-Geun;Lee Sang-Jin;Moon Heung-Man;Lee Sang-Hoon
    • Journal of the Korean Institute of Gas
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    • v.8 no.1 s.22
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    • pp.37-47
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    • 2004
  • Pressure swing adsorption (PSA) process using CMS as an oxygen purifier was developed to produce high purity oxygen over $99\%$ with high productivity. The cyclic performances such as purity, recovery, and productivity of PSA process were compared experimentally and theoretically under the non-isothermal condition. A binary ($O_2$/Ar 95:5 vol.$\%$) and two kinds of ternary ($O_2/Ar/N_2$ 95:4:1 and 90:4:6 vol.$\%$) mixtures were used as feed gases. The developed process with the consecutive two blowdown steps produced the oxygen with $99.8\%$ purity and $56\%$ recovery from $95\%$ oxygen containing feed. However, in the feed with $90\%$ oxygen, the $O_2$ Purity was decreased up to $97.3\%$. In addition, because the cyclic performances of the suggested process was significantly affected by the diffusion rate, the non-isothermal model with the the modified LDF model was applied for the process simulation. The concentration-dependent rate parameter of the applied rate model was incorporated with the Langmuir isotherm.

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A Study on Genetically Optimized Fuzzy Set-based Polynomial Neural Networks (진화이론을 이용한 최적화 Fuzzy Set-based Polynomial Neural Networks에 관한 연구)

  • Rho, Seok-Beom;Oh, Sung-Kwun
    • Proceedings of the KIEE Conference
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    • 2004.11c
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    • pp.346-348
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    • 2004
  • In this rarer, we introduce a new Fuzzy Polynomial Neural Networks (FPNNs)-like structure whose neuron is based on the Fuzzy Set-based Fuzzy Inference System (FS-FIS) and is different from that of FPNNs based on the Fuzzy relation-based Fuzzy Inference System (FR-FIS) and discuss the ability of the new FPNNs-like structurenamed Fuzzy Set-based Polynomial Neural Networks (FSPNN). The premise parts of their fuzzy rules are not identical, while the consequent parts of the both Networks (such as FPNN and FSPNN) are identical. This difference results from the angle of a viewpoint of partition of input space of system. In other word, from a point of view of FS-FIS, the input variables are mutually independent under input space of system, while from a viewpoint of FR-FIS they are related each other. In considering the structures of FPNN-like networks such as FPNN and FSPNN, they are almost similar. Therefore they have the same shortcomings as well as the same virtues on structural side. The proposed design procedure for networks' architecture involves the selection of appropriate nodes with specific local characteristics such as the number of input variables, the order of the polynomial that is constant, linear, quadratic, or modified quadratic functions being viewed as the consequent part of fuzzy rules, and a collection of the specific subset of input variables. On the parameter optimization phase, we adopt Information Granulation (IG) based on HCM clustering algorithm and a standard least square method-based learning. Through the consecutive process of such structural and parametric optimization, an optimized and flexible fuzzy neural network is generated in a dynamic fashion. To evaluate the performance of the genetically optimized FSPNN (gFSPNN), the model is experimented with using gas furnace process dataset.

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