16 research outputs found

    Removal of recalcitrant organic compounds from an industrial complex effluent by heterogeneous Fenton-type treatment

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    Because of their chemical complexity, industrial chemi-mechanical pulping effluents are evaporated and burned, in spite of the high associated cost involved in these processes. The aim of this study was to remove recalcitrant compounds from this kind of wastewater using a Fenton-type treatment. The main parameters involved in the process and their influence on the results were determined. Homemade catalysts based on CuO, Fe2O3, NiO and ZnO, supported on γ-Al2O3 have been tested for catalytic oxidation, and the CuO/γ- Al2O3 catalysts showed the greatest effect on total organic carbon (TOC) reduction (52.7%). A series of twolevel factorial experiments was subsequently applied to evaluate the most favorable range of conditions for CuO/γ-Al2O3 application. The studied variables were hydrogen peroxide concentration ([H2O2], g/L), active phase content (metal oxide supported on alumina, %), mass of catalyst (metal oxide/alumina system, g), and reaction temperature (°C). The highest reduction of all parameters was obtained at the superior level of all variables with CuO/γ-Al2O3, achieving reductions of chemical oxygen demand (COD) and TOC between 40 and 50%. Increasing catalyst mass did not produce additional benefit. This variable has a significant effect only on the reduction of aromatic compounds. At its low level, reduction in aromatic content exceeded 80%. Color reduction was influenced only by temperature (maximum reduction of 90%)Fil: Covinich, Laura Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; ArgentinaFil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; ArgentinaFil: Fenoglio, Rosa Juana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentin

    Geopolymers based on spent catalyst residue from a fluid catalytic cracking (FCC) process

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    This paper assesses the use of alkali activation technology in the valorization of a spent fluid catalytic cracking (FCC) catalyst, which is a residue derived from the oil-cracking process, to produce geopolymer binders. In particular, the effects of activation conditions on the structural characteristics of the spent catalyst- based geopolymers are determined. The zeolitic phases present in the spent catalyst are the main phases participating in the geopolymerization reaction, which is driven by the conversion of the zeolitic material to a highly Al-substituted aluminosilicate binder gel. Higher alkali content and SiO2/Na2O ratio lead to a denser structure with a higher degree of geopolymer gel formation and increased degree of crosslinking, as identified through 29Si MAS NMR. These results highlight the feasibility of using spent FCC catalyst as a precursor for geopolymer production.This study was sponsored by research scholarship BES-2008-002440 and EEBB-2011-43847 from the Ministerio de Ciencia y Tecnologia of Spain, the European regional development fund (FEDER), and the Universitat Politecnica de Valencia (Spain). The participation of SAB and JLP was funded by the Australian Research Council through the Discovery Projects program, and also including partial funding through the Particulate Fluids Processing Centre, a Special Research Centre of the ARC. The authors wish to acknowledge the Advanced Microscopy Facility at The University of Melbourne for assistance with the electron microscopy experiments conducted in this study.Rodriguez Martinez, ED.; Bernal, SA.; Provis, JL.; Gehman, JD.; Monzó Balbuena, JM.; Paya Bernabeu, JJ.; Borrachero Rosado, MV. (2013). Geopolymers based on spent catalyst residue from a fluid catalytic cracking (FCC) process. Fuel. 109:493-502. https://doi.org/10.1016/j.fuel.2013.02.053S49350210

    PAX5α and PAX5β mRNA expression in breast Cancer: Relation to serum P53 and MMP2

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    Background: Many studies evaluated the role of paired box gene 5 (PAX5) in breast cancer. However, few investigated PAX5α and PAX5β isoforms individually. Objective: The aim of the present study is to evaluate mRNA expression of PAX5α and PAX5β in breast cancer and assessing their underlying pathological roles through investigating their correlations to matrix metalloproteinase2 (MMP2), p53 and cancer antigen 15-3 (CA15-3). Methods: Evaluation of PAX5α and PAX5β RNA expression in breast tissue samples was done by real-time PCR, serum MMP2 and p53 by ELISA and CA15-3 by chemiluminescent immunoassay in 55 infiltrating ductal carcinoma patients, 25 fibroadenoma patients and 15 control females who underwent plastic breast surgery. Results: PAX5α RNA was reduced while PAX5b RNA was elevated in breast cancer patients compared to other groups (p < 0.01). The best cutoff value of PAX5α was 61.15 with 78.2% sensitivity and 90% specificity and for PAX5β it was P2.01 with 83.6% sensitivity and 82.5% specificity. The RNA expression of PAX5β was higher in advanced grades and stages (p < 0.01), and significantly correlated to p53 (r: 0.51, p < 0.01), and CA15-3 (r: 0.45, p < 0.01). Moreover, PAX5α was negatively correlated to PAX5β (r: 0.42, p < 0.01), p53 (r: 0.53, p < 0.01) and MMP2 (r: 0.22, p < 0.05). Conclusions: The downregulation of PAX5α with upregulation of PAX5β RNA expressions could highlight the possible oncogenic role of PAX5 as a transcriptional factor in tumorigenesis and progression of breast cancer

    Needs assessment for the establishment of master's degree programs in respiratory care in the Kingdom of Saudi Arabia

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    Background: Despite recent advancements in the respiratory care (RC) profession, no single institution in the Kingdom of Saudi Arabia (KSA) offers a master's degree program in RC. Methods: A nationwide and validated survey was used to explore the current needs and interests in establishing RC master’s degree programs in the KSA. The process included representatives from the healthcare industry, universities, and professional societies. Results: A total of 1250 stakeholders across the KSA completed the survey. The sample includes 722 (58%) males, 504 (40%) respiratory therapists, 547 (44%) students, 138 (11%) leaders, and 61 (5%) were academic respondents. Most respondents were from Central 491 (39%) and Eastern 307 (25%) regions, with 1003 (80%) of the total sample worked or studied in governmental sectors. 574 (82%) of the leaders and RTs had Bachelor degree and 430 (61%) of them had 1-5 years working experience. According to 80% of the employers and employees, only 0-5% of the RTs in their organization had a master's degree. The calculated mean % of the agreement (agree/strongly agree) on the needs was 83% in all needs’ assessment items, which shows a great support for establishing a master’s in RC to meet the personal, professional and society needs. The mean % of the agreement for the level of interests among all participants was 86%, indicating a great level of interests in establishing a master degree in RC. The agreement % on the needs assessment and level of interests in establishing a master degree in RC in KSA were ≥80% in each stakeholder group. Conclusion: There are obvious needs and interests in establishing master’s degree programs in RC in the KSA. A master's degree in RC should be established to address the growing needs for advanced RC services throughout the nation and enhance RC research
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