Effects of peat and water quality parameters on groundwater arsenic contamination in Bangladesh

To clarify the effect of peat and groundwater quality parameters on groundwater arsenic (As) contamination, As concentrations and the source of nitrogen (N) in groundwater and peat, and oxidation‐reduction potential (ORP) and ammonium‐N concentration of groundwater were compared between As‐contaminated and uncontaminated areas in Bangladesh. Groundwater in the contaminated area had a reducing ORP with a high ammonium‐N concentration, whereas groundwater in the uncontaminated area had a non‐reducing ORP with a low ammonium‐N concentration. Peat was present only in the contaminated area, whose As concentration was very high, indicating the critical role of peat in groundwater As contamination. The source of N in peat and groundwater was identified as chemical N fertilizer. N present in peat and groundwater served as a nutrient, enhancing microbial activity. In the reducing ORP condition, As was thought to be released intensively to groundwater by the mechanism of reductive release.     

Note: Exploring gender differences in construction research: a European perspective

Research suggests that women in academia face problematic career paths as a result of masculine cultures and horizontal segregation. At the same time, research in the construction sector has documented the barriers women face in entering and remaining in construction careers. Construction academia is investigating in this exploratory study to determine whether gender disparities found in academic research generally are valid in this field. As there is a lack of data on women in academia, particularly by sub‐disciplines, scientific publication is used to explore gender differences and similarities. Publication is a significant area where gender disparities have been found in other fields and an area that can have substantial consequences for career progression in academia. The data are from a wider European study exploring women’s participation in construction research and are based on secondary analysis of statistics from the ISI Web of Knowledge. Gender differences in publication are found to exist, suggesting that women are under‐represented in construction research at a similar rate to women in engineering and technology academia. However, there are important differences between the different areas of construction research, which indicate that women may not face the same barriers and difficulties in all areas of construction academia. It also highlights the need for further research to investigate horizontal segregation and the gendered nature of publication, citation and collaboration in construction research.     

A lateral flow protein microarray for rapid and sensitive antibody assays

Protein microarrays are useful tools for highly multiplexed determination of presence or levels of clinically relevant biomarkers in human tissues and biofluids. However, such tools have thus far been restricted to laboratory environments. Here, we present a novel 384-plexed easy to use lateral flow protein microarray device capable of sensitive (<30 ng/mL) determination of antigen-specific antibodies in ten minutes of total assay time. Results were developed with gold nanobeads and could be recorded by a cell-phone camera or table top scanner. Excellent accuracy with an area under curve (AUC of 98% was achieved in comparison with an established glass microarray assay for 26 antigen-specific antibodies. We propose that the presented framework could find use in convenient and cost-efficient quality control of antibody production, as well as in providing a platform for multiplexed affinity-based assays in low-resource or mobile settings.     

Poly(benzoxazine-co-urethane)s: A new concept for phenolic/urethane copolymers via one-pot method

Historically, applications for traditional phenolic resin/polyurethane materials are limited due to the inherently weak thermal stability of urethane-phenolic linkage and slow reaction rate. A novel concept has been developed to produce phenolic resin/polyurethane copolymers via benzoxazine chemistry. Through one-pot synthesis, a series of linear poly(benzoxazine-co-urethane) materials has been synthesized via the reaction of a newly developed dimethylol functional benzoxazine monomer with 4,4′-methylene diphenyl diisocyanate and poly(1,4-butyleneadipate). The structure of the copolymers has been characterized by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy (NMR). The copolymers in the film forms have been further thermally treated for crosslinking to produce crosslinked poly(benzoxazine-co-urethane) via the ring opening polymerization of cyclic benzoxazine moieties in the main-chain. The tensile properties of the films have been studied and compared with those of traditional high performance materials. The thermal properties of the crosslinked copolymers have also been studied by dynamic mechanical analysis, and thermogravimetric analysis (TGA).     

Enhancing mechanical properties of gel‐spun polyvinyl alcohol fibers by iodine doping

High strength polyvinyl alcohol (PVA) fibers with a conventional degree of polymerization of 1500 were prepared by doping iodine with PVA spinning solution. The iodine‐doped PVA (I‐PVA) aqueous solution was extruded into cold methanol that provides dark purple PVA‐iodine complex gel fibers. Only a small amount of iodine was required to enhance drawability and molecular orientation by reducing the interaction between PVA chains. An increase of ca. 10% in the maximum draw ratio of the doped fibers compared with that of undoped PVA translated into values for the tensile strength, 2.2 Giga‐Pascal (GPa), and initial modulus (47 GPa) that were more than 30% higher than those of the neat PVA fiber. Easier chain slippage of molecules in the amorphous segments of the I‐PVA fiber during drawing leads to increased orientation in these segments, which is believed to be the source of the improvements in mechanical properties. POLYM. ENG. SCI., 2011. © 2010 Society of Plastics Engineers     

Synthesis, absorption and fluorescence of hydrazone colorants based on pyrrolinone esters

Ten azo dyes were prepared by diazotization of a series of electronically different para substituted anilines and subsequent azo coupling of these diazonium salts with ethyl 4,5-dihydro-5-oxo-2-aryl(1H)pyrrole-3-carboxylate as a the coupling component. All of the dyes were confirmed as keto-hydrazone tautomers and were found as a mixtures of E- and Z-isomers with respect to the exocyclic CN bond by ¹H-NMR spectroscopy. The absorption spectra are all similar irrespective of substituent and solvent. By comparison the fluorescence is strongly dependent on the electronic character of the substituents. All compounds fluoresce in a low temperature solvent glass and in the solid state and only the 4-cyanophenyl and 4-nitrophenyl derivatives show fluorescence in solution at room temperature. The spectroscopic behavior is explained in terms of competition between E/Z isomerization and fluorescence after excitation.     

Realization of two-dimensional recursive digital filters using the mixed Cauer form†

The application of the mixed cauer continued fraction expansion to synthesis of two-dimensional recursive digital filters is presented. Examples are provided to show how to perform a mixed cauer expansion on two-dimensional transfer functions and eventually obtain canonic digital ladder filter structures. Furthermore, a test for two-dimensional mixed-cauer continued fraction expansion which at the same time determines the expansion coefficients is included.     

A design for hydrogen production and dispensing for northeastern United States,along with its infrastructural development timeline

Countries are trying to reduce their energy consumption, fossil fuel usage, and greenhouse gas emissions. Recent guidelines generated by various government agencies indicate an increase in the fuel economy, with a reduction in green house gases. The use of both alternative fuel vehicles and renewable energy sources is thus necessary toward achieving this goal. This paper proposes a hydrogen fueling infrastructure design for the Northeastern United States. The design provides an implementation plan for a period of 13 years (from 2013 to 2025). This design gives priority to customer convenience with minimum additional investments for its implementation. Extensive research has been conducted on generating a hydrogen supply from factories and other potential sources that can satisfy demand in the region. Markers (e.g. population density, traffic density, legislation, and growth pattern) have driven the process of demand estimation.