Biobutanol: science,engineering, and economics

Among several liquid alternative fuels, biobutanol has shown great promise because of its very similar properties to gasoline. This review provides an overview of research activities in acetone–butanol–ethanol (ABE) fermentation over the past two and a half decades. We have addressed seven important facets of ABE fermentation, viz. biochemistry, microbial cultures, alternative substrates, solvent recovery, fermentation mode and reactor designs, mathematical modeling, and economics. Development of mutant strains having higher yield, selectivity and tolerance to inhibition, and search for cheap alternative substrates for fermentation are most important thrust areas in biobutanol production. New and efficient processes have been developed for in situ removal and recovery of the ABE solvents. Several rigorous kinetic and physiological models for fermentation have been formulated, which form useful tool for optimization of the process. These research activities have been reviewed in this paper. Finally, we have summarized studies on the economic viability of large‐scale ABE fermentation processes employing various process designs, substrates, and microbial cultures. With the use of new strains, inexpensive substrates, and superior reactor designs, economic potential of ABE fermentation has been found to be highly attractive. Research efforts in science, engineering, and economics of ABE fermentation have brought biobutanol close to commercialization as liquid alternate fuel. Copyright © 2011 John Wiley & Sons, Ltd.     

Effect of color temperature on appearance of paintings exhibited under LED lighting

Colour of light modulates the appearance of displayed artifacts in exhibition. To understand the effect of light on appearance of paintings, few studies have experimented to establish a relation between pleasantness with the correlated colour temperature (CCT) of light. However, some studies have found that CCT has no significant effect on pleasant appearance of painting. Therefore, in this article, an experiment with a qualitative (questionnaire on semantic differential scale, N = 30) approach was designed to understand the effect of CCT on appearance of paintings exhibited under LED lights. The findings from the experimental result depict that the appearance of paintings changes due to different CCTs of LEDs having the same illuminance. In addition, the result reveals that for both mediums of paintings considered in this study, in comparison to warm white LED and artificial daylight LED, cool white LED has appeared to be more pleasant having moderately warm feelings to the viewers.     

Multifunctional glow discharge analyzer for spacecraft monitoring

In this study the main objective was to develop and demonstrate a glow discharge microplasma coupled to a miniature spectrometer for detection of fire signatures from pyrolyzing and burning spacecraft materials. Our experimental results demonstrate that combustion-produced carbonaceous aerosols can serve to identify the burning materials. Demonstrating versatility for chemistry analysis, the plasma detector could differentiate carbonaceous aerosols with different C/H ratios and distinguish inorganic samples such as salts and metal oxides from carbonaceous aerosols. In addition, in situ analysis of aerosol samples validated the microplasma’s analytical utility by linearity of its optical emission intensity with aerosol elemental composition.     

0.40% Bipolar Strain in Lead Free BNT–KNN System Modified with Li,Ta and Sb

In this work we demonstrate a large electric field‐induced bipolar strain ~0.40% in Li, Ta and Sb modified BNT–KNN ((1?x) Bi_0.5Na_0.5TiO₃–xK_0.47Na_0.47Li_0.06 Nb_0.74Sb_0.06Ta_0.2O₃) system. The morphotropic phase boundary (MPB) of the system between rhombohedral and tetragonal phases lies in the range 0.02 ≤ x ≤ 0.06, beyond which all compositions (up to x < 0.15) were found to be tetragonal. A clear trade‐off between the large strain values and achievable d₃₃, k_p for a particular composition was noted. It is shown that while for x = 0.03, d₃₃ 169 pC/N, k_p 49% and strain ~0.13% were obtained, for x = 0.08 with 0.40% strain, d₃₃ and k_p values decreased drastically.     

Grain Size Distributions after Single Hit Deformation of a Segregated, Commercial Nb-Containing Steel: Prediction and Experiment

The present investigation examines the applicability of the Dutta–Sellars equations in predicting the recrystallized grain sizes following deformation for a 0.046 wt pct Nb-bearing, commercially produced steel with a segregated solute content (from continuous casting). The investigation considered initial unimodal and bimodal grain size distributions before deformation that were generated by reheating the steel to 1498 K and 1423 K (1225 °C and 1150 °C), respectively. It was found that the reheated grain size distribution (separated into grain size classes) could be related to the solute-rich (smaller grain size classes) and solute-depleted (larger grain size classes) regions. The use of these relationships and a simple halving of the grain size within the distribution on recrystallization (used previously for homogenized samples of this steel) were found to be appropriate in the grain size class-based use of the Dutta–Sellars equations with respect to mode and maximum grain sizes after hot deformation and holding. This approach successfully predicted (confirmed by experiment) the grain size distribution after deformation in the presence of Nb segregation from continuous casting.     

Delta-opioid stimulation by BW373U86 promotes autonomic reactivity to stressors and alters attention-related cardiac responses in rabbits.

The nonpeptide δ-opioid agonist BW373U86 (3 to 300 μg/kg) was tested in rabbits for effects on heart rate, cardiac orienting and Pavlovian conditioned responses to tones, and unconditioned cardiac and somatomotor responses to signaled and unsignaled shocks. BW373U86 did not alter shock-evoked somatomotor reflexes and had few effects on the development or retention of Pavlovian conditioned heart rate discrimination. However, BW373U86 appeared to modulate cardiac conditioning indirectly, by facilitating sympathetic reflexes evoked by the signaled stressor, and the dose effect was ∪-shaped within the dose range tested. The pronounced tachycardiac effect of BW373U86 was completely blocked, or rapidly reversed, by the selective δ-opiate antagonist naltrindole. BW373U86 was more potent in increasing signaled than unsignaled shock-evoked tachycardia, suggesting release of an endogenous substance (e.g., a δ-opioid) because of the Pavlovian conditioning contingency. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The simultaneous addition of styrene maleic anhydride copolymer and multiwall carbon nanotubes during melt‐mixing on the morphology of binary blends of polyamide6 and acrylonitrile butadiene styrene copolymer

The effect of simultaneous addition of multiwall carbon nanotubes (MWNTs) and a reactive compatibilizer (styrene maleic anhydride copolymer, SMA) during melt‐mixing on the phase morphology of 80/20 (wt/wt) PA6/ABS blend has been investigated. Morphological analysis through scanning and transmission electron microscopic analysis revealed finer morphology of the blends in presence of SMA + MWNTs. Fourier transform infrared spectroscopic analysis indicated the formation of imide bonds during melt‐mixing. Non‐isothermal crystallization studies exhibited the presence of a majority faction of MWNTs in the PA6 phase of 80/20 (wt/wt) PA6/ABS blend in presence of SMA + MWNTs. Rheological analysis, dynamic mechanical thermal analysis, and thermogravimetric analysis have demonstrated the compatibilization action of simultaneous addition of a reactive compatibilizer (SMA copolymer) and MWNTs in PA6/ABS blends. An attempt has been made to investigate the role of simultaneous addition of SMA copolymer and MWNTs on the morphology of 80/20 (wt/wt) PA6/ABS blend through various characterization techniques. POLYM. ENG. SCI., 55:457–465, 2015. © 2014 Society of Plastics Engineers     

Efficient Chemical and Enzymatic Syntheses of FAD Nucleobase Analogues and Their Analysis as Enzyme Cofactors**

Flavin adenine dinucleotide (FAD) is an essential redox cofactor in cellular metabolism. The organic synthesis of FAD typically involves coupling flavin mononucleotide (FMN) with adenosine monophosphate, however, existing synthesis routes present limitations such as multiple steps, low yields, and/or difficult-to-obtain starting materials. In this study, we report the synthesis of FAD nucleobase analogues with guanine/cytosine/uracil in place of adenine and deoxyadenosine in place of adenosine using chemical and enzymatic approaches with readily available starting materials, achieved in 1–3 steps with moderate yields (10–57 %). We find that the enzymatic route using Methanocaldococcus jannaschii FMN adenylyltransferase (MjFMNAT) is versatile and can produce these FAD analogues in high yields. Further, we demonstrate that Escherichia coli glutathione reductase is capable of binding and using these analogues as cofactors. Finally, we show that FAD nucleobase analogues can be synthesized inside a cell from cellular substrates FMN and nucleoside triphosphates by the heterologous expression of MjFMNAT. This lays the foundation for their use in studying the molecular role of FAD in cellular metabolism and as biorthogonal reagents in biotechnology and synthetic biology.     

Prioritizing towards a green export portfolio for India: An environmental input–output approach

Proponents of free trade have often hailed international trade as an engine of economic growth. However, the foreign trade sector, like many other sectors in developing countries, frequently involves these countries walking a tightrope between their developmental objectives and environmental goals. In this regard, prioritizing for developing a ‘green’ yet internationally competitive export portfolio provides a quintessential win–win solution to the problem. This study factors in both environmental benignity (indicated by total CO₂ emission intensity) as well as trade competitiveness (indicated by revealed comparative advantage index) in identifying the ‘ideal’ Indian export portfolio. The analysis calculates the level of direct and indirect emissions from the foreign trade sector (exports and imports) using the environmental input–output (EIO) matrix for 2003/04 for India that has been jointly developed by researchers from Keio University, Japan, and The Energy and Resources Institute (TERI), New Delhi. The derived basket is compared to the current portfolio to estimate the potential saving from compositional changes and to suggest directions for policymaking to emphasize or de-emphasize the export of certain categories of exports.