{"title":"The Kinetics of the Oxidation of Lysine by μ-Peroxo-Bridged Binuclear Cobalt (III) Complex of Succinimide in Aqueous Hydrochloric Acid Medium","authors":"A. Adetoro, S. Idris, A. D. Onu, F. Okibe","doi":"10.2478/ast-2018-0006","DOIUrl":"https://doi.org/10.2478/ast-2018-0006","url":null,"abstract":"Abstract Kinetics of oxidation of Lysine (Lys) and mechanisms by μ-peroxo bis[bis(ethylenediamine)succinimidato-dicobalt(III)]dinitratedihydrate; [LCo(μ-O2)CoL](NO3)2.2H2O (L = suc(en)2), hereafter the complex, was investigated at 420 nm wavelength of maximum absorption of the complex under the conditions hydrogen ions concentration = 1.8 × 10−2 mol dm−3, temperature = 24 ± 1 °C, [LCo(μ-O2)CoL2+] = 1.4 × 10−4 mol dm−3 and ionic strength = 0.5 mol dm−3. First order in [LCo(μ-O2)CoL2+] and [Lys] were obtained but inverse first order in [H+]. The proposed overall rate equation is as shown: Rate=(k1k2+K1k3k41[H+])[LCo(μO2)CoL2+][Lys] $$Rate = ({{k_1 } over {k_2 }} + {{K_1 k_3 } over {k_4 }}{1 over {[H^ + ]}})[LCo(mu O_2 )CoL^{2 + } ][Lys]$$ Rate of the reaction decreases when hydrogen ions concentration increase and exhibited converse effect with increase in concentration of ionic strength from 0.1 – 1.3 mol dm−3. Added cations and anions affected the reaction rate and the Michaelis-Menten plot passed through the origin indicating no absence of intermediate complex in the electron transfer processes. Putting all the results obtained together, the most probable reaction mechanism is in favour of outer-sphere and an appropriate rate law is established using steady state approximation.","PeriodicalId":7998,"journal":{"name":"Annals of Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85577651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Carbonaceous Soot from Thermal Decomposition of Kerosene: A Pioneering Report for Paint Preservation","authors":"O. Obidi, O. Okoli, S. Nwachukwu","doi":"10.2478/ast-2018-0004","DOIUrl":"https://doi.org/10.2478/ast-2018-0004","url":null,"abstract":"Abstract Bacterial resistance to conventional paint biocides is widely documented. However, an investigation regarding the preservative potential of carbonaceous soot as a viable alternative is novel. Fresh paint samples (SA, SB and SC) were collected in duplicates from a reputable paint manufacturing company in Lagos, Nigeria. SA was produced with conventional paint biocide, SB and SC were without biocide. All samples were inoculated with 0.032 × 106 cfu/mL of Pseudomonas aeruginosa PA01 (NC 002516.2) previously isolated from spoilt paints and identified by the 16S rDNA analysis. SB was supplemented with crude soot (10 g/L of distilled water) at 200 mL v/v. The preservative efficiency of soot was investigated by monitoring the bacterial population (BP), optical density (OD600nm), viscosity (VIS), the transmittance (TR) and specific gravity (SG) of the samples bi-weekly for 14 weeks. BP increased drastically from 0.032-31.61 × 106 and from 0.032-112.93 × 106 in SA and SC respectively. In contrast, SB increased from 0.032-24.63 × 106 by week 4 but reduced from 24.63 – 10.95 × 106 by week 14. The OD of SA increased from 1.55 to 1.98 by week 8 and decreased to 1.74 by week 14. SB had a decrease from 1.60 to 1.49 by week 4 and increased to 1.63 by week 14, while SC increased from 1.59 to 2.54 by the 14th week.TR increased from 1.80 to 2.30 and 1.25 to 2.20 in SA and SC respectively. In contrast, TR decreased from 2.00 to 1.25 in SB. The viscosity and specific gravity values of all the samples decreased with time with the highest decrease observed in SC and the lowest in SB. The test crude soot showed preservative potential in paints.","PeriodicalId":7998,"journal":{"name":"Annals of Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79685970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}