• Title/Summary/Keyword: radical form

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Effect of Hydrocarbons on the Promotion of $NO-NO_{2}$ Conversion in NonThermal Plasma DeNOx Treatment (비열 플라즈마에 의한 NO의 산화에 탄화수소 첨가제가 미치는 영향)

  • Shin, Hyun-Ho;Yoon, Woong-Sup
    • 한국연소학회:학술대회논문집
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    • 2000.05a
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    • pp.178-188
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    • 2000
  • In the present study, a systematic chemical kinetic calculations were made to investigate the augmentation of $NO-NO_{2}$ conversion due to the addition of various hydrocarbons (methane, ethylene, ethane, propene, propane) in the nonthermal plasma treatment. It is included in the present conclusion that the reaction between hydrocarbon and oxygen radicals induced by electron collision, is believed to be a primarily process for triggering the overall NO oxidation and the eventual NOx reduction. Upon the completion of the initiating step, various radicals (OH, $HO_{2}$ etc.) successively produced by hydrocarbon decomposition form the primary path of $NO-NO_{2}$ conversion. When the initiating step is not activated, hydrocarbon consumption rate appeared to be very low, thereby the targeted level of NO conversion can only be achieved by the addition of more input energy. Present study showed ethylene and propene to have higher affinity with 0 radical under all conditions, thereby both of these hydrocarbons show very fast and efficient $NO-NO_{2}$ oxidation. It was also shown that propene is superior to ethylene in the aspect of NOx removal.

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Cervical Esophageal Cancer (경부식도암)

  • 노영수;김진환
    • Korean Journal of Bronchoesophagology
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    • v.9 no.1
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    • pp.30-38
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    • 2003
  • Cancers of the cervical esophagus occur uncommonly, but treatment is remaining a challenging problem and surgery demands special knowledge of abdominal, thoracic, and neck surgery. The primary risk factor is chronic heartburn, leading to a sequence of esophagitis, Barrett's esophagus, reflux esophagitis and etc. Among the various treatment modalities, Surgery is still a mainstay of treatment. The main aim of surgery is not only oncologically adequate resection but also preservation or restoration of physiologic functions, such as deglutition and phonation. Surgical treatment of cervical esophageal cancer is influenced by special problems arising from tumor factors, patient factors and surgeon factors. Complete clearance of loco-regional disease and prevention of postoperative complications are of particular importance for the improvement of long-term survival in patients with these cancers. So the cervical and thoracic extension of these tumors usually required an extensive lymphadenectomy with primary resection. Radical resection of the primary site almostly include sacrifice of the larynx, but the voice could be rehabilitated with various methods, such as tracheoesophageal prosthesis or tracheoesophageal shunts, etc. Restoration of the esophageal conduit can be performed using gastric or colon interposition, radial forearm free flap or jejunum free flap, etc. Recently, the advances of radiation therapy and chemotherapy will enable less extended resections with greater rates of laryngeal preservation. At initial presentation, up to 50% to 70% of patients will have advanced locoregional or distant disease with virtually no chance for cure. Patients with advanced but potentially resectable esophageal cancer are generally treated by surgery with some form of neoadjuvant chemotherapy, radiotherapy, or both, with 5-year survivals in the 20% to 30% range. So the significant adverse factors affecting survival should be taken into account to select the candidates for surgery.

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Poly(vinyl pyrrolidone) Conjugated Lipid System for the Hydrophobic Drug Delivery

  • Lee, Hye-Yun;Yu, Seol-A;Jeong, Kwan-Ho;Kim, Young-Jin
    • Macromolecular Research
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    • v.15 no.6
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    • pp.547-552
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    • 2007
  • Water soluble polymer, poly(vinyl pyrrolidone) was chosen to conjugate with 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-(succinyl) (N-succinyl DPPE) to make a new drug delivery system. PVP with an amine group (amino-PVP) was polymerized by free radical polymerization. The amine group of amino-PVP was conjugated with the carboxylic group of N-succinyl DPPE. The resultant conjugate could form nanoparticles in the aqueous solution; these nanoparticles were termed a lipid-polymer system. The critical aggregation concentration was measured with pyrene to give a value of $1{\times}10^{-3}g/L$. The particle size of the lipid-polymer system, as measured by DLS, AFM and TEM, was about 70 nm. Lipophilic component in the inner part of the lipid-polymer system could derive the physical interaction with hydrophobic drugs. Griseofulvin was used as a model drug in this study. The loading efficiency and release profile of the drug were measured by HPLC. The loading efficiency was about 54%. The release behavior was sustained for a prolonged time of 12 days. The proposed lipid-polymer system with biodegradable and biocompatible properties has promising potential as a passive-targeting drug delivery carrier because of its small particle size.

Wind induced vibrations of long electrical overhead transmission line spans: a modified approach

  • Verma, Himanshu;Hagedorn, Peter
    • Wind and Structures
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    • v.8 no.2
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    • pp.89-106
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    • 2005
  • For estimating the vortex excited vibrations of overhead transmission lines, the Energy Balance Principle (EBP) is well established for spans damped near the ends. Although it involves radical simplifications, the method is known to give useful estimates of the maximum vibration levels. For very long spans, there often is the need for a large number of in-span fittings, such as in-span Stockbridge dampers, aircraft warning spheres etc. This adds complexity to the problem and makes the energy balance principle in its original form unsuitable. In this paper, a modified version of EBP is described taking into account in-span damping and in particular also aircraft warning spheres. In the first step the complex transcendental eigenvalue problem is solved for the conductor with in-span fittings. With the thus determined complex eigenvalues and eigenfunctions a modified energy balance principle is then used for scaling the amplitudes of vibrations at each resonance frequency. Bending strains are then estimated at the critical points of the conductor. The approach has been used by the authors for studying the influence of in-span Stockbridge dampers and aircraft warning spheres; and for optimizing their positions in the span. The modeling of the aircraft warning sphere is also described in some detail.

A Study on the Architectural Construction of Balenciaga's works (Balenciaga의 작품에 나타난 건축적 형태미에 관한 연구)

  • 장애란
    • Journal of the Korean Society of Costume
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    • v.21
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    • pp.5-18
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    • 1993
  • The purpose of this study is to identify the architectural construction of Balenciaga's works. He was perfectionist in tailoring which was based on architectural thought, and couturier who could design, cut, sew and fit a whole gar-ment. Balenciaga has never followed any fashion trend but his own. He designed from within himself, according to his own sensitivity to fashion. Like Chanel, he mad clothes in which women can be comfortable, move in, and get on and off with a minimum of effort. He ap-plied radical shapes to flattering ends, for his clothes echoed movements and gestures, never determined them. He achieved the perfect harmony between the body and the garment, freeing the spirit of the woman within. Reflec-tion his respect for women, Balenciaga never contorted or restriced their bodies. He did not depend on hoops and petticoats to hold out the skirts of his evening dresses but on well-balanced, architectural construction. Therefore in order to identify the architec-tural consturuction, this study hypothesizes (1) the effect of mass and volume, (2) the ef-fect of weight and support, (3) the effect of complexity and simplicity, (4) the effect of line and rhythm etc. The architectural beauty of form in Balenciaga's works are especially based on simplicity and support.

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Two Cases of Primary Splenic Hydatid Cyst in Greece

  • Vezakis, Antonios;Dellaportas, Dionysios;Polymeneas, George;Tasoulis, Marios Konstantinos;Chondrogiannis, Constantinos;Melemeni, Aikaterini;Polydorou, Andreas;Fragulidis, George Panagiotis
    • Parasites, Hosts and Diseases
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    • v.50 no.2
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    • pp.147-150
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    • 2012
  • Cystic disease of the spleen is an uncommon entity in general population. Most cases result from parasitic infection by Echinococcus granulosus, a form called splenic hydatid disease (SHD), with a reported frequency of 0.5-6.0% within abdominal hydatidosis. On the contrary, an isolated splenic involvement of hydatid disease is very uncommon even in endemic regions. Two cases of primary SHD managed with open and laparoscopic radical surgery in our department are reported herein. Primary SHD is a rare entity with non-specific symptoms underlying clinical suspicion by the physician for prompt diagnosis. Surgical treatment is the mainstay therapy, while laparoscopic approach when feasible is safe, offering the advantages of laparoscopic surgery.

Quality Characteristics and Storage Stability of Bread with Allium hookeri Powder (삼채가루 첨가 식빵의 제조조건 최적화 및 저장성 연구)

  • Lee, HeeJeong;Baik, Jae-Eun;Joo, Nami
    • The Korean Journal of Food And Nutrition
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    • v.27 no.2
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    • pp.318-329
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    • 2014
  • The purpose of this study was to determine the optimal mixing ratio of Allium hookeri powder and butter in the preparation of bread. The experiment was designed according to the central composite design for estimating the response surface, which demonstrated 10 experimental points, including 2 replicates for Allium hookeri powder and butter. Further, the mechanical and sensory properties of test materials were measured. A canonical form and perturbation plot conveyed the influence of each ingredient on the final product mixture. Overall, the measurement results of the mechanical properties showed a significant increase or decrease in dough pH, sweetness, volume, weight, height, specific volume, a & b-value of crumb and, springiness (p<0.05). Moreover, the sensory measurements demonstrated a significant improvement in color, appearance, texture, moistness and, overall quality. As a result, the optimum formulation from the numerical and graphical methods was calculated as 22.65 g of Allium hookeri powder and 47.77 g butter. After optimization, DPPH free radical scavenging activity, total phenolic content, and total plate counts over 10 days were evaluated. In sum, the results revealed the antioxidant and antibiotic actions of bread with Allium hookeri powder.

Polymerization of Methyl Methacrylate Initiated by Cobalt (II) Nitrate (질산코발트 (II)에 의한 Methyl Methacrylate의 중합)

  • Jang-oo Lee;Dong-ho Lee;Tae-oan Ahn
    • Journal of the Korean Chemical Society
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    • v.19 no.6
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    • pp.463-467
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    • 1975
  • The polymerization of methyl methacrylate(MMA) initiated by cobalt (II) nitrate in tetrahydrofuran (THF) has been studied. From the results of kinetic studies, the overall polymerization rate (Rp) could be expressed as following; $R_p=k\;[cobalt(Ⅱ)\;nitrate]^{0.5}\;[MMA]^{1.5}$ By considering the effects of chelating agent on the polymerization rate, it could be assumed that the monomer, MMA might form a coordination complex with cobalt(II) nitrate. In the presence of radical inhibitor hydroquinone, the inhibition time was observed. And the apparent overall activation energy was calculated to be 14.0 kcal/mole.

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The Effect of Samchoolgunbitanggamibang of the growth of rats (삼출건비탕가미방(蔘出健脾湯加味方)이 흰쥐의 성장에 미치는 영향)

  • Beak, Jung-Han;Koo, Jin-Suk
    • The Journal of Pediatrics of Korean Medicine
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    • v.20 no.1
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    • pp.49-67
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    • 2006
  • Objectives : The purpose of this study is to find out the effect of antioxidation related to aging of Cheongeumyeonsudan which is written on Dongui-bogam experimentally. Method : 14 weeks aged SD albino rats were separated into uncontrolled group, controlled group and CGY group. As controlled and CGY groups were induced aging by subcutaneous injection of D-galactose, at the same time we administered the extract of Cheongeumyeonsudan to CGY group for 6 weeks. After then we drew blood from each group, and took measurements; the activity of SOD, GSH-px, catalase in erythrocytes, TBARS value, concentration of total lipid, tryglycende, total cholesterol, HDL-cholesterol in blood plasma. Results : The activities of SOD, GSH-px in erythrocytes were significantly increased in the CGY group compared with control group. The activity of catalase showed a tendency to increase, but it was nor remarkable. The concentration of total lipid, the values of TBARS and total cholesterol was significantly decreased in the CGY group compared with control group, and the concentration of plasma HDL-cholesterol was not remarkable. The concentration of tryglycende in plasma showed a tendency to decreased. Conclusions : it is suggested that Cheongeumyeonsudan decreased the activities of free radical, the concentration of lipid in plasma and generate enzyme which form lipid peroxide.

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Structure of Edge Flame in a Methane-Oxygen Mixing Layer (메탄/순산소 혼합층에서 edge flame의 구조)

  • Choi, S.K.;Kim, J.;Chung, S.H.;Kim, J.S.
    • 한국연소학회:학술대회논문집
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    • 2006.04a
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    • pp.149-156
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    • 2006
  • Structure of edge flame established in a mixing layer, formed between two uniformly flowing pure $CH_4$ and pure $O_2$ streams, is numerically investigated by employing a detailed methane-oxidation mechanism. The numerical results exhibited the most outstanding distinction of using pure oxygen in the fuel-rich premixed-flame front, through which the carbon-containing compound is found to leak mainly in the form of CO instead of HC compounds, contrary to the rich $CH_4-air$ premixed flames in which $CH_4$ as well as $C_2H_m$ leakage can occur. Moreover, while passing through the rich premixed flame, a major route for CO production, in addition to the direct $CH_4$ decomposition, is found to be $C_2H_m$ compound formation followed by their decomposition into CO. Beyond the rich premixed flame front, CO is further oxidized into $CO_2$ in a broad diffusion-flame-like reaction zone located around moderately fuel-rich side of the stoichiometric mixture by the OH radical from the fuel-lean premixed-flame front. Since the secondary CO production through $C_2H_m$ decomposition has a relatively strong reaction intensity, an additional heat-release branch appears and the resulting heat-release profile can no longer be seen as a tribrachial structure.

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