• Title/Summary/Keyword: Rh.B

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Sonochemical Synthesis of $PbMoO_4$ Nanoparticles and Evaluation of its Photocatalytic Activity

  • Uresti, Diana B. Hernandez;De la Cruz, Azael Martinez;Martinez, Leticia M. Torres;Lee, Soo-Wohn
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2011.05a
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    • pp.49.2-49.2
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    • 2011
  • $PbMoO_4$ nanoparticles were successfully obtained in the presence of ethylene glycol (EG) with the assistance of a prolonged sonication process. The nanoparticles were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS) and adsorption-desorption $N_2$ isotherms (BET). The catalyst prepared sonochemically showed higher photocatalytic activity than $PbMoO_4$ prepared by solid-state reaction in the degradation reactions of rhodamine B (rhB), indigo carmine (IC), orange G (OG), and methyl orange (MO) under UV-Vis light radiation. In order to elucidate aspects of the degradation mechanism of the organic dyes, some experimental variables were modified such as pH, $O_2$ level in solution, and radiation source. In general, the photocatalytic activity for the degradation of organic dyes followed the sequence IC>OG>rhB>MO.

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Comparison of Dynamic Sorption and Hygroexpansion of Wood by Different Cyclic Hygrothermal Changing Effects

  • Yang, Tiantian;Ma, Erni
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.2
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    • pp.191-203
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    • 2016
  • To investigate the dynamic sorptive and hygroexpansive behaviors of wood by different cyclic hygrothermal changing effects, poplar (populus euramericana Cv.) specimens, were exposed to dynamic sorption processes where relative humidity (RH) and temperature changed simultaneously in sinusoidal waves at 75-45% and $5-35^{\circ}C$ (condition A) and where RH changed sinusoidally at 75-45% but temperature was controlled at $20^{\circ}C$ (condition B), both for three cyclic periods of 1, 6, and 24 h. Moisture and dimensional changes measured during the cycling gave the following results: Moisture and transverse dimensional changes were generally sinusoidal. Moisture and dimensional amplitude increased with increasing cyclic period but all were lower for thicker specimens. The amplitude ratio of condition A to condition B ranged from 1.0 to 1.6 with the maximum value of 1.57 occurring at the shortest cyclic period, not as much as expected. T/R increased as cyclic period increased or specimen thickness decreased. T/R from condition B was weaker than that from condition A. Sorption and swelling hysteresis existed in both conditions. Sorption hysteresis was negatively related to cyclic period but in positive correlation with specimen thickness. Sorption hysteresis was found more obvious in condition B, while moisture sorption coefficient and humidity expansion coefficient showed the opposite results.

A Comparison of Efficiency of Decolorizing Rhodamine B using Lab-Scale Photocatalytic Reactors : Slurry Reactor, IWCR and PFBR

  • Na, Young-Soo;Lee, Tae-Kyung;Lee, Song-Woo;Lee, Chang-Han;Kim, Do-Han;Park, Young-Seek;Song, Seung-Koo
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.10 no.S_4
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    • pp.157-164
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    • 2001
  • The performance of fluidized-bed reactor with Photomedia, immobilized TiO$_2$ onto the porous ceramic ball using a sol-gel method has been studied in this work. A simple model substrate, dilute Rhodamine B (RhB), was decolorized at room temperature. For the purpose of comparison, the slurry reactor and the Inner Wall Coated Reactor (IWCR) were used. The aim of this work was to develop the photocatalytic fluidized bed reactor (PFBR) through contrasting the photodegradability of various reactors such as the TiO$_2$slurry reactor, the inner-wall coated reactor (IWCR). In this study, the RhB was decolorized in three types of reactor. Even though the reaction rate constant of PFBR was lower than that of slurry reactor, PFBR had the advantages of preventing the wash-out of photocatalyst, so it can be operated continuously.

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Synthesis of solar light responsive ZnO/TaON photocatalysts and their photocatalytic activity (태양광 응답형 ZnO/TaON 나노 복합체의 제조 및 광촉매 특성 평가)

  • Kim, Tae-Ho;Jo, Yong-Hyeon;Lee, Su-Wan
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2014.11a
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    • pp.256-257
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    • 2014
  • The effects of the preparation conditions of ZnO-modified TaON on the photocatalytic activity for degradation of rhodamine B dye (Rh. B) under simulated solar light were investigated. The ZnO/TaON nanocomposite were prepared by loading particulate $Ta_2O_5$ with ZnO using different ZnO contents, followed by thermal nitridation at 1123 K for 5 h under $NH_3$ flow (20 ml min.1). The asprepared samples were characterized by XRD, UV-Vis-DRS, and SEM-EDX. The results revealed that the band gap energy absorption edge of as prepared nanocomposite samples was shifted to a longer wavelength as compared to ZnO and $Ta_2O_5$, and the 60 wt% ZnO/TaON nanocomposite exhibited the highest percentage (99.2 %) of degradation of Rh. B and the highest reaction rate constant ($0.0137min^{-1}$) in 4 h which could be attributed to the enhanced absorption of the ZnO/TaON nanocomposite photocatalyst. Hence, these results suggest that the ZnO/TaON nanocomposite exhibits enhanced photocatalytic activity for the degradation of rhodamine B under simulated solar light irradiation in comparison to the commercial ZnO, $Ta_2O_5$, and TaON.

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Photodegradation of Rhodamine B in $TiO_2$ suspension

  • Na, Young-Soo;Kim, Ji-Hye;Lee, Tae-Kyung;Lee, Song-Woo;Song, Seung-Koo
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.10 no.S_3
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    • pp.149-155
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    • 2001
  • In recent years, rapid technological advances in the textile and dyeing industry have yielded benefits to society but have also generated new and significant environmental problems. The treatment alternatives applicable for the removal of color vary, depending upon the type of dye wastewater Advanced oxidation processes are considered to provide more permanent merits. One of these oxidation treatments attracting much attention is photocatalytic oxidation, which uses TiO$_2$ due to its non-toxic, insoluble liquid as well as a highly reactive nature under UV irradiation. This study sets out to demonstrate the effect of photocatalyst dosage, dye concentrations, pH and light intensity on color removal efficiency under aerobic conditions. The results of this study show Rhodamine B(RhB) was not decolorized when a dye solution was exposed only to air or treated by TiO$_2$ only In the presence of both TiO$_2$ and UV light, however, the presence of RhB decreased up to 95 % within 60minutes. The more addition TiO$_2$ and the more diluted dye solution, showed a higher removal rate.

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Enhancing the Efficacy of Burkholderia cepacia B23 with Calcium Chloride and Chitosan to Control Anthracnose of Papaya During Storage

  • Rahman, M.A.;Mahmud, T.M.M.;Kadir, J.;Rahman, R. Abdul;Begum, M.M.
    • The Plant Pathology Journal
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    • v.25 no.4
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    • pp.361-368
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    • 2009
  • The efficacy of the combination of Burkholderia cepacia B23 with 0.75% chitosan and 3% calcium chloride ($CaCl_2$) as a biocontrol treatment of anthracnose disease of papaya caused by Colletotrichum gloeosporioides, was evaluated during storage. The growth of B. cepacia B23 in papaya wounds and on fruit surfaces was not affected in presence of chitosan and $CaCl_2$ or combination throughout the storage period. The combination of B. cepacia B23 with chitosan-$CaCl_2$ was more effective in controlling the disease than either B. cepacia B23 or chitosan or other combination treatments both in inoculated and naturally infected fruits. Combining B. cepacia B23 with chitosan-$CaCl_2$ gave the complete control of anthracnose infection in artificially inoculated fruits stored at $14^{\circ}C$ and 95% RH for 18 days, which was similar to that obtained with fungicide $benocide^{(R)}$. Moreover, this combination offered a greater control by reducing 99% disease severity in naturally infected fruits at the end of 14 days storage at $14^{\circ}C$ and 95% RH and six days post ripening at $28\pm2^{\circ}C$, which was superior to that found with $benocide^{(R)}$ or other treatments tested. Thus, postharvest application of B. cepacia B23 with chitosan-$CaCl_2$ as enhancers represents a promising alternative to synthetic fungicides for the control of anthracnose in papaya during storage.

A Study on the Heat and Moisture Transport Properties of Vapor-Permeable Waterproof Finished Fabrics for Sports Wear (스포츠웨어용 투습방수직물의 열·수분이동 특성에 관한 연구)

  • Son, Bu Hun;Kim, Jin-A;Kwon, Oh Kyung
    • Fashion & Textile Research Journal
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    • v.2 no.3
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    • pp.220-226
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    • 2000
  • This study was to determine the characteristics of vapor-permeable waterproof finished fabric by the coating method. 4 different kinds of coating fabrics (A : wet, porous, polyurethane, B : dry, no porous, polyurethane, C : shape memory polyurethane and D : dry, porous polyurethane) were used, which were developed recently With this sample, moisture transport rate ($40^{\circ}C$, 45%RH & $40^{\circ}C$, 95%RH), changes of coating side's shape by washing times, water repellency rate, contracted length, qmax, heat conductivity, heat keeping rate, heat keeping rate with cotton, heat keeping rate on humidity temperature and humidity within clothing etc. were checked. And it was done in a climate chamber under $20{\pm}2^{\circ}C$, $65{\pm}5%RH$. The results of this study were as follow; In the moisture vapor transmission of sample B and C increased on high temperature and high humidity while sample A and D decreased, on this condition. Qmax rate had high relation with ground fabric's surface properties and the order was A>C>D>B. Heat conductivity had high relation with thickness and surface properties. Heat keeping rates on sweat condition showed around half percents of heat keeping rates on normal condition, but had no relation with moisture vapor transport rate. Changes of the fabric's properties by washing times were different in accordance with the construction of fabrics and the coating resin. Sample C had tow heat keeping rate on the high temperature and humidity and high heat keeping rate on the low temperature and humidity Moisture transport rate of vapor-permeable waterproof finished fabrics had high relation with the properties of ground fabrics on low humidity condition, but on the high humidity condition, it was highly related with the properties of coating resin.

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Comparison of Microbial and Physico-chemical Quality Characteristics in Kimchi-fermented Sausages with Sodium Nitrite and Green Tea Extract (아질산염과 녹차 추출물의 첨가에 따른 김치 발효 소시지의 미생물 및 이화학적 품질 특성 비교)

  • Kang, Sun-Moon;Kim, Tae-Sil;Cho, Soo-Hyun;Park, Beom-Young;Lee, Sung-Ki
    • Journal of Animal Science and Technology
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    • v.54 no.4
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    • pp.299-305
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    • 2012
  • This study was conducted to compare the microbial and physico-chemical quality characteristics in Kimchi-fermented sausages added with sodium nitrite (SN) and green tea extract (GTE). The sausages were fermented at $24^{\circ}C$/RH 89% for 17 hr and then dried at $10^{\circ}C$/RH 70~80% for 9 days. The total bacteria count, lactic acid bacteria count and pH value ranged from 8.7 Log CFU/g sausage, 8.1~8.3 Log CFU/g sausage and 4.35~4.36, respectively, at 9 d of ripening, but did not show significant differences during ripening among all sausages. The lipid oxidation (TBARS) was inhibited by both GTE and SN, but GTE had lower (p<0.05) inhibitory effect, compared with SN. The $b^*$ value of GTE-added sausage was higher than that of the control sausage, but $a^*$ and $b^*$ values of SN-added sausage remained higher than other sausages during ripening. Therefore, it had lower effect on lipid oxidation and color stabilities than SN while GTE improved the lipid oxidation stability in Kimchi-fermented sausage. However, both GTE and SN did not influence the growth of lactic acid bacteria.

Significance of ABO-Rh Blood Groups in Response and Prognosis in Breast Cancer Patients Treated with Radiotherapy and Chemotherapy

  • Cihan, Yasemin Benderli
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.9
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    • pp.4055-4060
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    • 2014
  • Background: To evaluate whether ABO-Rh blood groups have significance in the treatment response and prognosis in patients with non-metastatic breast cancer. Materials and Methods: We retrospectively evaluated files of 335 patients with breast cancer who were treated between 2005 and 2010. Demographic data, clinic-pathological findings, treatments employed, treatment response, and overall and disease-free survivals were reviewed. Relationships between clinic-pathological findings and blood groups were evaluated. Results: 329 women and 6 men were included to the study. Mean age at diagnosis was 55.2 years (range: 26-86). Of the cases, 95% received chemotherapy while 70% were given radiotherapy and 60.9% adjuvant hormone therapy after surgery. Some 63.0% were A blood group, 17.6% O, 14.3% B and 5.1% AB. In addition, 82.0% of the cases were Rh-positive. Mean follow-up was 24.5 months. Median overall and progression-free survival times were 83.9 and 79.5 months, respectively. Overall and disease-free survival times were found to be higher in patients with A and O blood groups (p<0.05). However rates did not differ with the Rh-positive group (p=0.226). In univariate and multivariate analyses, ABO blood groups were identified as factors that had significant effects on overall and disease-survival times (p=0.011 and p=0.002). Conclusions: It was seen that overall and disease-free survival times were higher in breast cancer patients with A and O blood groups when compared to those with other blood groups. It was seen that A and O blood groups had good prognostic value in patients with breast cancer.