Application of channel flow double electrode to the study on platinum dissolution during potential cycling in sulfuric acid solution

The applicability of a channel flow double electrode (CFDE) as an in situ monitoring method of Pt dissolution during potential cycling in 0.5 M H₂SO₄ solution at 25 °C was investigated. In the CFDE, Pt ions (Ptⁿ⁺) dissolved from a platinum working electrode were detected by reducing them to Pt on a gold collector electrode which was placed at the downstream. The detection of the Pt dissolution by the collector current was confirmed by EPMA analysis of the collector electrode surface. In anodic scan, a rise of the collector current above 1.05 V clearly indicated the platinum dissolution. The collector current showed two different rates of dissolution, i.e. a lower rate from 1.05 to 1.3 V where only one layer of oxide (PtO) is formed and the higher rate from 1.3 to 1.46 V where two layers of oxides (probably PtO/PtO₂) are formed. The collector current, in the cathodic scan, clearly showed two different reduction peaks due to the Pt deposition, which was confirmed by EPMA analysis. On the basis of collector current, the rate and potential range of the Pt dissolution are discussed.     

Achieving global environmental benefits through local development of clean energy? The case of small hilly hydel in India

Energy and development are closely intertwined. Yet, increasing fossil fuel-based energy consumption contributes significantly to environmental problems both locally and globally. This article explores the interlinkages between local livelihood and environmental benefits from the provision of energy to remote rural households through small hydropower development. The analysis is based on research carried out around a large development project designed to assist the Government of India in the optimum utilization of small hydropower resources in the Himalayan and sub-Himalayan regions. There are about 100,000 villages in India that are not connected to electricity supply, many of them in the hilly regions with ample hydropower potential. The project aimed to demonstrate the utility of and options for providing electricity to such villages through clean mini-hydro. The article addresses the nature of the impacts of the demonstration small hydel schemes on the local communities, to what extent they translate into environmental benefits both locally and globally, and the perceptions and participation of the local communities in these small hydro schemes. The study explores the impacts of the schemes on financial capital, natural capital, social capital, physical capital, human capital, and gender equity in the local communities. It further provides a discussion on the links between local and global environmental benefits. Overall, it is found that the schemes’ impacts both on the local communities and the environment are mostly marginally positive or neutral, although achieving clearly demonstrable benefits would require major upscaling of the effort involving broader changes than possible under this project. Furthermore, it is argued that some of the assumptions behind the project design were faulty. Involvement of the local communities and direct livelihood benefits to them are essential for the long-term sustainability of the small hydro schemes. The discussion and conclusions are intended to provide guidance to programmes and projects that aim to promote environmentally sound energy in the rural areas of developing countries.     

Novel moisture-cured hyperbranched urethane alkyd resin for coating application

A hyperbranched polyol (HBP) was synthesized using dipentaerythritol as a core material and 2,2-bis(methylol) propionic acid as a chain extender. This was reacted with varying concentrations of soya fatty acid to make hyperbranched alkyd (HBA) resins. The HBA resins containing unreacted hydroxyl groups were reacted with isophorone diisocyanate at NCO/OH ratio of 1.6:1 to make high solid hyperbranched urethane alkyd (HBUA) resins. The excess NCO content in the HBUA resins was used to cure with atmospheric moisture, and thus moisture-cured HBUA coatings were formed. The resins were characterized by FTIR, and ¹³C NMR spectroscopic analysis. A series of such resins were made using different fatty acid/isocyanate ratios with respect to the hydroxyl groups present in the HBP. The effect of compositions on the mechanical and weathering properties of the cured resins was investigated. It was observed that there was an optimum fatty acid–isocyanate ratio in terms of the requirements of solvent, mechanical and weathering properties of the resin. The requirement of solvents for formulating HBUA coatings is much lower compared to linear alkyd-based coatings. The present study reveals that the moisture-cured HBUA resins can be used as a binder material in the field of low-pollution weather-resistance coatings.     

Nanostructure Evolution Mechanisms During Slow Load‐Cycling of Oriented HDPE/PA Microfibrillar Blends as a Function of Composition

Oriented precursors of MFCs consisting of HDPE and PA6 or PA12 are studied during strain‐controlled slow load‐cycling. In the PA6‐containing blends a strongly retarded nanostrain response is detected. Compatibilization induces nanostrain heterogenization. Stress fatigue is lower in the PA12 blends, but hardly decreased by the compatibilizer. Selective migration of the compatibilizer into a disordered semi‐crystalline fraction of the HDPE matrix can explain the findings. The semi‐crystalline HDPE entities in PA6 blends appear more disordered than in PA12‐blends. An analysis of the HDPE nanostructure evolution during cycling reveals epitaxial strain crystallization. Uncompatibilized PA6 blends cycled about high pre‐strain show plastic flow but nanoscopic shrinkage in the semi‐crystalline stacks.

     

Toward single molecule detection of staphylococcal enterotoxin B: mobile sandwich immunoassay on gliding microtubules

An immunoassay based on gliding microtubules (MTs) is described for the detection of staphylococcal enterotoxin B. Detection is performed in a sandwich immunoassay format. Gliding microtubules carry the antigen-specific "capture" antibody, and bound analyte is detected using a fluorescent viral scaffold as the tracer. A detailed modification scheme for the MTs postpolymerization is described along with corresponding quantification by fluorescence spectroscopy. The resultant antibody-MTs maintain their morphology and gliding capabilities. We report a limit of detection down to 0.5 ng/mL during active transport in a 30 min assay time and down to 1 ng/mL on static surfaces. This study demonstrates the kinesin/MT-mediated capture, transport, and detection of the biowarfare agent SEB in a microfluidic format.     

Concentrations of Foliar Quercetin in Natural Populations of White Birch (Betula pubescens) Increase with Latitude

We investigated latitudinal and regional variations in the composition and concentrations of foliar flavonoids and condensed tannins in wild populations of white birch (Betula pubescens EHRH) in a large climatic transect in Finland. Concentrations of quercetin derivatives were correlated positively with latitude. By contrast, the concentrations of apigenin and naringenin derivatives were correlated negatively with latitude. These compound-specific latitudinal gradients compensated each other, resulting in no changes in the concentration of total flavonoids. Our results thus demonstrate a qualitative, but not quantitative, latitude-associated gradient in the foliar flavonoids in white birch. Due to higher antioxidant capacity of the quercetin derivatives in relation to other flavonoids, the qualitative change can reflect higher adaptation to light in the north than south. An investigation on a regional scale in the northern boreal zone showed that the temperature sum was correlated positively and soil P concentration was correlated negatively with the concentrations of foliar flavonoid, while the concentration of condensed tannins was correlated with slope. The variation in concentrations of flavonoids at large-scale geographical patterns is in line with the conjecture that foliar flavonoids are synthesized for protection against photooxidative stress.     

Treatment of Escherichia coli O157:H7 inoculated alfalfa seeds and sprouts with electrolyzed oxidizing water

Electrolyzed oxidizing water is a relatively new concept that has been utilized in agriculture, livestock management, medical sterilization, and food sanitation. Electrolyzed oxidizing (EO) water generated by passing sodium chloride solution through an EO water generator was used to treat alfalfa seeds and sprouts inoculated with a five-strain cocktail of nalidixic acid resistant Escherichia coli O157:H7. EO water had a pH of 2.6, an oxidation-reduction potential of 1150 mV and about 50 ppm free chlorine. The percentage reduction in bacterial load was determined for reaction times of 2, 4, 8, 16, 32, and 64 min. Mechanical agitation was done while treating the seeds at different time intervals to increase the effectiveness of the treatment. Since E. coli O157:H7 was released due to soaking during treatment, the initial counts on seeds and sprouts were determined by soaking the contaminated seeds/sprouts in 0.1% peptone water for a period equivalent to treatment time. The samples were then pummeled in 0.1% peptone water and spread plated on tryptic soy agar with 5 microg/ml of nalidixic acid (TSAN). Results showed that there were reductions between 38.2% and 97.1% (0.22-1.56 log(10) CFU/g) in the bacterial load of treated seeds. The reductions for sprouts were between 91.1% and 99.8% (1.05-2.72 log(10) CFU/g). An increase in treatment time increased the percentage reduction of E. coli O157:H7. However, germination of the treated seeds reduced from 92% to 49% as amperage to make EO water and soaking time increased. EO water did not cause any visible damage to the sprouts.     

The registered dietitian in primary care: the Hamilton experience.

The Hamilton Health Service Organization Nutrition Program integrates nine registered dietitians (RDs) into the offices of 80 family physicians (FPs) at 50 sites in Hamilton, Ontario. The program is based on a shared care model, in which FPs and RDs work collaboratively to provide nutrition services aimed at prevention, treatment, and management of nutrition-related problems. In addition to their clinical role, dietitians in the program are involved in health promotion, disease prevention and early intervention strategies, interdisciplinary collaboration, building links with community services, and research. The RDs' specialized knowledge, skills, and experience allow them to provide a wide range of services that complement and augment those of the FP. This model is consistent with Canadian health care reform recommendations and offers significant benefits for both health care providers and consumers.     

Determination of co-metabolism for 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT) degradation with enzymes from Trametes versicolor U97

Trametes versicolor U97 isolated from nature degraded 73% of the 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT) in a malt extract liquid medium after a 40-d incubation period. This paper presents a kinetic study of microbial growth using the Monod equation. T. versicolor U97 degraded DDT during an exponential growth phase, using glucose as a carbon source for growth. The growth of T. versicolor U97 was not affected by DDT. DDT was degraded by T. versicolor U97 only when the secondary metabolism coincided with the production of several enzymes. Furthermore, modeling of several inhibitors using the partial least squares function in Minitab 15, revealed lignin peroxidase (98.7 U/l) plays a role in the degradation of DDT. T. versicolor U97 produced several metabolites included a single-ring aromatic compound, 4-chlorobenzoic acid.     

Organic Geochemical Evaluations of Bituminous Rock and Coals in Miocene Himmetoglu Basin (Bolu,Turkey)

Abstract

The studied area is a lake basin located in Bolu basin in Turkey. In the basin, from Upper Cretaceous to Upper Miocene 3,000-m thickness sediments were deposited. Upper Miocene Himmetoglu formation consisted of sandstone, claystone, and marl. To the middle level of the formation are located coal, bituminous limestone, and bituminous shales. In the basin, there are two coal beds whose thicknesses range from 1 to 13 m. The coals are easily breakable and black in color. In the coal beds exists some bituminous limestone and bituminous shales, and their thicknesses are between 5 and 45 cm. The amount of organic matter of the bituminous rocks from the Upper Miocene Himmetoglu formation are between 6.83 and 56.34 wt%, and the amount of organic matter of the bituminous limestone from the formation are between 13.58 and 57.16 wt%. These values indicate that these rocks have very good source potential. According to hydrogen index (HI), S ₂/S ₃, HI-T _max, and HI-OI (oxygen index) parameters, kerogen types of the bituminous rocks and coals belonging to Upper Miocene Himmetoglu formation are Type I, Type II, and Type III. In accordance with HI, S ₂/S ₃, HI-T _max, and HI-OI parameters, the bituminous rocks and coals from the Upper Miocene Himmetoglu formation are mostly immature.