Decolorization of synthetic dyes using a copper complex with glucaric acid

Selected azo, acridine, triphenyl methane, anthraquinone and thiazine-based dyes were decolorized using a catalytic system consisting of Cu(II)/glucaric acid/H(2)O(2). More than 90% decolorization was obtained with 100 ppm Acridine Orange, Azure B, Chicago Sky Blue, Crystal Violet, Methyl Orange, Poly B-411, Reactive Black 5, Reactive Blue 2, and Remazol Brilliant Blue R within 24 h. Seventy to eighty percent decolorization was achieved within the first 6 h. The decolorizaton was not affected by pH. The involvement of hydroxyl radicals produced in the system in the decolorization of the dye molecules was confirmed by electron spin resonance study.     

Lead induced spermatoxicity in mouse and MPG treatment

Protective efficacy of MPG (2-mercaptopropionyl glycine) was studied against the toxic effects of lead acetate in Swiss albino mice. The animals were treated with single dose of lead acetate @ 180, 200 and 250 mg/kg b.wt. in presence and absence of MPG. The results indicated that the body weight was slightly higher in MPG treated groups on day 10 as compared to only respective lead treated groups in all the three dose level. However, significantly lower body weight was observed in both lead treated and lead along with MPG treated groups as compared to control. Patten of mortality is similar in both lead treated and lead plus MPG treated groups. Conspicuous degenerative changes in testicular tissues and elevation in sperm head shape abnormality were observed in both lead treated and lead along with MPG treated groups but the sperm head shape abnormality and damage were more in lead treated groups as compared to lead plus MPG treated groups. But this difference was non-significant between the two groups. These observations suggest that MPG may not be significantly effective against lead induced damage in testicular tissues at cellular level. However, MPG is able to maintain slightly lower level of sperm abnormality in all the three dose level as compared to their respective lead treated groups. Further, studies are needed to find out the optimum dose of MPG for protection against the lower doses of lead induced lethality as MPG is not significantly effective against the higher doses of lead.     

The occurrence of glycolic acid in coastal sea water

A reasonably fast and reliable chemical method for the determination of glycolic acid in sea water is described in detail. It consists of adsorption of glycolic acid by alumina, followed by extraction with sulphuric acid and then colorimetry. The overall efficiency of recovery of this method, which is standardized internally, is approximately 67%, and about 20-fold concentration of glycolic acid is achieved. Using this method, the occurrence of glycolic acid in Ipswich Bay (Gulf of Maine, USA) was studied over a period of 6 months and was found to fluctuate between 0 and 80 g/l. The zero values occurred in January, when the phytoplankton chlorophyll values were also at their winter minimum.     

Preparation of jet engine range fuel from biomass pyrolysis oil through hydrogenation and its comparison with aviation kerosene

The Bio-oil was produced from the pyrolysis of agricultural wastes (Eucalyptus sawdust) and discarded soybean frying oil. The temperature of the pyrolysis system was initiated at 28°C and increased to 850°C. Atmospheric distillation of crude bio-oil was performed and a fraction at a temperature range 160–240°C (pyrolysis oil) was separated and subjected to GC-MS, ¹H-NMR, TGA and FTIR analysis to identify the different properties and compounds present in pyrolysis oil. It was noticed that there was an abundance of oxygen and nitrogen containing compounds as well as other reactive species in pyrolysis oil. To reduce the amount of these species, the pyrolysis oil was subjected to hydrogenation in the presence of NiMo as a catalyst. After hydrogenation, the atmospheric distillation of hydrogenated bio-oil was performed and another fraction at temperature range 160–240°C (hydrogenated bio-oil) was separated and analyzed by the same techniques. It was noticed that during hydrogenation, more than 60% oxygenated and other reactive species were converted into hydrocarbons. Hydrogenated bio-oil showed very similar physico-chemical properties such as distillation curve, density, viscosity, freezing point, flash point, the presence of hydrocarbons and enthalpy of combustion as aviation kerosene also known as QAV-1.     

Spectrophotometric determination of trifluralin in commercial formulations and agricultural samples using factorial design

A simple spectrophotometric method was developed for determination of trifluralin in commercial formulation and food samples. The method was based on the hydrolysis of trifluralin with sodium hydroxide to form 2,6-dinitro-4-trifluoromethylaniline. The resultant aniline group was diazotized with nitrate in acidic media and the diazotized product was coupled with β-naphthol to form red colored product having λ_max 550 nm. The reaction conditions were optimized for hydrolysis as well as for the diazotization reaction. The Beer’s law was obeyed over the range of 0.2–17 μg mL⁻¹ with molar absorptivity of 1.5 × 10⁴ L mol⁻¹ cm⁻¹. The relative standard deviation was found to be 3.6%. A two level factorial design of 2³ was used for optimization of all parameters. The influence of different factors and their interactions on the final azo dye formation were also studied from these factorial designs. The method has been applied successfully for the analysis of commercial formulations and agricultural samples. The recovery for the determination of trifluralin was found to be in the range 95–97%.     

Developing biofuels industry in small economies: Policy experiences and lessons from the caribbean basin initiative

With increasing concerns about rising energy demand and cost, diminishing oil reserves, and climate change, Central American and Caribbean (CAC) nations have the opportunity to become producers of low-carbon sustainable biofuels for domestic consumption and foreign exchange earnings. While the region has a number of comparative advantages for developing a vibrant biofuels sector, including favorable climate and significant agricultural experience, the experience under the favorable Caribbean Basin Initiative (CBI) has exposed significant technical and non-technical barriers that must be overcome. Using information compiled through interviews with industry executives, government policy makers and civil society stakeholders, we provide a critical analysis of this experience focusing on non-technical barriers to investment. Survey results suggest that political uncertainty, poor regulatory frameworks, and lack of institutional commitment and business incentives are the main non-technical barriers. Having laid out the challenges, we propose potential policy positions to stimulate growth of the regional biofuels sector. Results point to the need to prioritize enhancing national legislation, developing risk prevention plans, creating supply and demand side incentives and increasing multilateral collaboration. While these findings are derived from the Caribbean Basin experience, they may also be applicable to small economies in other regions that are considering policies for biofuels industry development.     

Low mating frequency of queens in the stingless bee<Emphasis Type="Italic"> Scaptotrigona postica</Emphasis><Superscript>1</Superscript> and worker maternity of males

Kin selection models of intracolonial conflict over the maternity of males predict that social hymenopteran workers should favour the production of sons and nephews over brothers when the effective mating frequency (m_e) of the queen is low (m_e<2) but that they should police other workers' reproductive efforts and favour the production of brothers when m_e>2. Stingless bees have been used to support these models in that m_e within the group is considered low and workers are thought often to monopolise the parentage of males. We genetically analysed 20 worker and 20 male pupae from each of 10 colonies of the stingless bee Scaptotrigona postica (= Scaptotrigona aff. depilis) using six microsatellite loci and demonstrate queen monandry in eight nests and apparent low m_e in the other two. However, four colonies contained an additional matriline, possibly due to queen supersedure (serial polygyny), which complicated their genetic structure. Across colonies, workers were responsible for the maternity of 13% of all males. These data are broadly in agreement with predictions from kin selection theory, though the question remains open as to why workers do not secure a greater share of male maternity in this and other stingless bee species in which workers are more closely related to nephews than brothers.     

Assessment of chemical process hazards in early design stages

A new method called SREST-layer-assessment method with automated software tool is presented that in a hierarchical approach reveals the degree of non-ideality of chemical processes with regard to SHE (safety, health and environment) aspects at different layers: the properties of the chemical substances involved (substance assessment layer (SAL)), possible interactions between the substances (reactivity assessment layer (RAL)), possible hazard scenarios resulting from the combination of substances and operating conditions in the various equipments involved (equipment assessment layer (EAL)), and the safety technologies that are required to run a process safely and in accordance with legal regulations (safety-technology assessment layer (STAL)). In RAL, EAL and STAL the main focus is put on process safety. A case study is used to show the principles of the method. It is demonstrated how the method can be used as a systematic tool to support chemical engineers and chemists in evaluating chemical process safety in early process development stages.