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31.
In this study, the thermo-oxidative stability of two new phosphorylated derivatives of cardol, a compound from the cashew (Anacardium occidentale L.) industry waste CNSL (cashew nutshell liquid), were evaluated. The antioxidant capacity of these new molecules upon two mineral oils, NH10 and NH20 were also studied by thermogravimetric analysis (TG/DTG), observing the onset and offset temperatures variation. The results showed that both MP and DP Cardol increased considerably the onset and offset temperatures of NH10 and NH20 oils.  相似文献   
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The effect of organic matter and fill time on anaerobic sequencing batch reactor (5 L, 30°C, 8-h cycles, 50 rpm) efficiency has been analyzed. Organic matter was increased by the influent concentration. Fill times investigated were in the batch mode and fed-batch followed by batch. In the batch mode organic matter removal were 93%, 81%, and 66% for influent concentration of 500, 1,000, and 2,000 mgCOD/L (0.6, 1.29, and 2.44 gCOD/L.d), respectively. At 3,000 mgCOD/L (3.82 gCOD/L.d) operational stability could not be achieved. Removal efficiency was improved by increasing the fill time, and was 85% for the 1,000 mgCOD/L condition and fill times of 2 and 4 h, and 80 and 77% for the 2,000 mgCOD/L condition and fill times of 2 and 4 h, respectively. Hence, gradual feeding seemed to improve and to smooth the profiles of organic matter and volatile acids along the cycle with 78 to 96 NmLCH4/gCOD.  相似文献   
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Electrochemical detection of nucleic acid base mismatches related to Apa I single nucleotide polymorphism (SNP) in the vitamin D receptor gene was performed successfully using 7‐dimethyl‐amino‐1,2‐benzophenoxazinium salt (Meldola's blue, MDB) with 10.9 pmol/100 μL of detection limit. MDB reduction signals obtained from probe, mismatch(probe‐SNP containing target) and hybrid(probe‐target) modified pencil graphite electrode(PGE) increased respectively. The sensor was able to clearly distinguish perfect match from mismatch DNA in a 30 min. detection time. Several factors affecting on the hybridization and indicator response are studied to maximize sensitivity and selectivity. The advantages of the biosensor are discussed in comparison with previous electrochemical assays for DNA hybridization.  相似文献   
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A system with n independent components which has a k-out-of-n: G structure operates if at least k components operate. Parallel systems are 1-out-of-n: G systems, that is, the system goes out of service when all of its components fail. This paper investigates the mean residual life function of systems with independent and nonidentically distributed components. Some examples related to some lifetime distribution functions are given. We present a numerical example for evaluating the relationship between the mean residual life of the k-out-of-n: G system and that of its components.  相似文献   
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Abstract  In this paper, we introduce new difference sequence spaces combining with de la Vallee-Poussin mean using by a sequence of modulus functions and ϕ -functions. We also studied connections between statistically convergence related with this space. Keywords Difference sequence, Modulus function, ϕ -function, De la Vallee-Poussin means, Statistical convergence Mathematics Subject Classification (2000) 46A45, 40F05, 46A80  相似文献   
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P(OMe3)3 reacts with RuCl3 · 3H2O to produce the complex trans-[Ru{P(OMe)3}4Cl2] from which the complexes trans-[Ru{P(OMe)3}4S2]2+ and cis-[Ru{P(OMe)3}2S4]2+ (S = Solvent) can be prepared by solvation in neutral and acidic solution, respectively. The aquation takes place with a specific rate of 1.0 × 10–2 min–1 (pH = 3.0) and 5.4 × 10–3 min–1 (pH 7.0) The trans-[Ru{P(OMe)3}4Cl2] complex has been characterized by elemental analysis; electronic spectra [max = 408 nm] ( = 1.7 × 102 M–1 cm–1), max = 250 nm ( = 3.5 × 103 M–1 cm–1) and a shoulder at = 280 nm ( 8.3 × 102 M–1 cm–1)]; cyclic voltametry ( = 0.75 V versus s.c.e.); HPLC (t R = 5.7 min); and 31P-n.m.r. ( = 131 p.p.m.). In acidic solutions the 31P-n.m.r. variations point to a reaction intermediate, characterized as the complex ion trans-[Ru{P(OMe)3}4S2]2+ ( = 136 p.p.m.) followed by the formation of the proposed product, cis-[Ru{P(OMe)3}2S4]2+ ( = 145 p.p.m.). For this same complex, at pH = 7.0, the results show the formation of the trans-[Ru{P(OMe)3}4S2]2+ ( = 136 p.p.m.). The HPLC results for the trans-[Ru{P(OMe)3}4Cl2] complex show that the different species are present at different pH values. In acidic media a less polar species (t R = 4.3 min) compared with the starting material (t R = 5.7 min) was formed. At neutral pH (t R = 4.6 min) the species generated were not modified, however they exhibited different properties from the species obtained at a lower pH.  相似文献   
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