Throwing New Light on the Reduction of CO2

While the chemical energy in fossil fuels has enabled the rapid rise of modern civilization, their utilization and accompanying anthropogenic CO₂ emissions is occurring at a rate that is outpacing nature's carbon cycle. Its effect is now considered to be irreversible and this could lead to the demise of human society. This is a complex issue without a single solution, yet from the burgeoning global research activity and development in the field of CO₂ capture and utilization, there is light at the end of the tunnel. In this article a couple of recent advances are illuminated. Attention is focused on the discovery of gas‐phase, light‐assisted heterogeneous catalytic materials and processes for CO₂ photoreduction that operate at sufficiently high rates and conversion efficiencies, and under mild conditions, to open a new pathway for an energy transition from today's “fossil fuel economy” to a new and sustainable “CO₂ economy”. Whichever of the competing CO₂ capture and utilization approaches proves to be the best way forward for the development of a future CO₂‐based solar fuels economy, hopefully this can occur in a period short enough to circumvent the predicted adverse consequences of greenhouse gas climate change.     

Lignosulfonates: effects on plant growth and survival and migration through the soil profile

The effects of Lignosite^#rm lignosulfonate, a refined lignosulfonate product that is obtained from the sulfite pulping process, on growth and survival of plants were investigated. Following applications of 0, 7500, 15,000 and 22,500 cm³#shm² to 32 plots within a forest plantation, the following were monitored: (1) live aboveground biomass of vascular plants, (2) growth of Douglar fir (Pseudotsuga menziesii) and (3) lignosulfonate migration through the soil profile. Live aboveground biomass of woody vegetation was not affected, and that of herbaceous plants was significantly decreased only at the two greatest application rates. Growth of the Douglas fir trees was not significantly affected. Lignosulfonates disappeared from the soil profile at the same rate regardless of initial concentration. Although it is not practical to use this material as a herbicide in western Washington, land application of lignosulfonates may be environmentally more attractive than traditional disposal methods.     

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The number of species in bloom in 25 m² permanent plots, which were located in grasslands subject to a range of management regimes, was monitored at regular intervals in 1986 and 1988. A single well‐defined peak of number of species in bloom occurred in early July (around day 190: 9 July) for all non‐mown sites. Only a minority of species flowered well away from the peak. It is recommended that management and interpretive strategies for grazed and unmanaged grasslands should concentrate on exploiting this phenomenon, whilst mowing regimes for amenity grasslands should be manipulated to provide colour and interest early and late in the season.     

Interaction dynamics of a spherical particle with a suspended liquid film

Hydrodynamics of collision interactions between a particle and gas‐liquid interface such as droplet/film is of keen interest in many engineering applications. The collision interaction between a suspended liquid (water) film of thickness 3.41 ± 0.04 mm and an impacting hydrophilic particle (glass ballotini) of different diameters (1.1–3.0 mm) in low particle impact Weber number ( ) range (1.4–33) is reported. Two distinct outcomes were observed—particle retention in the film at lower Weber number and complete penetration of the film toward higher Weber number cases. A collision parameter was defined based on energy balance approach to demarcate these two interaction regimes which agreed reasonably well with the experimental outcomes. It was shown that the liquid ligament forming in the complete penetration cases breaks up purely by “dripping/end pinch‐off” mechanism and not due to capillary wave instability. An analytical model based on energy balance approach was proposed to determine the liquid mass entrainment associated with the ligament which compared well with the experimental measurements. A good correlation between the %film mass entrained and the particle Bond number ( ) was obtained which indicated a dependency of Bo^1.72. Computationally, a three‐dimensional CFD model was developed to simulate these interactions using different contact angle boundary conditions which in general showed reasonable agreement with experiment but also indicated deficiency of a constant contact angle value to depict the interaction physics in entirety. The computed force profiles from computational fluid dynamics (CFD) model suggest dominance of the pressure force over the viscous force almost by an order of magnitude in all the Weber number cases studied. © 2015 American Institute of Chemical Engineers AIChE J, 62: 295–314, 2016     

Thermal Expansion of Alkaline‐Doped Lanthanum Ferrite Near the Néel Temperature

The thermal expansion and magnetic behaviors of divalent, alkaline‐doped lanthanum ferrites (La_0.9M_0.1FeO₃, M=Ca, Sr, Ba) were assessed using a combination of dilatometry, magnetometry, time‐of‐flight neutron diffraction, and high‐temperature X‐ray diffraction. Néel temperatures were determined through vibrating sample magnetometry and correlated well with changes in thermal expansion behavior observed during both dilatometry and X‐ray diffraction. The Néel temperatures observed for pure, Ca‐doped, Sr‐doped, and Ba‐doped lanthanum ferrites were 471°C, 351°C, 465°C, and 466°C, respectively. The effect of divalent substitutions on the magnetic behavior are attributed to charge compensation mechanisms and structural changes in the material.     

Influence of change in ether structure on the low temperature dielectric relaxation of some poly(ether imide)

Broad band dielectric relaxation spectra are reported on a range of polymers created by varying the ether segment in a series of poly(ether imide)s. Changes in the structure allow the effects of steric constraints on the local conformational dynamics of the polymer chain to be explored. These changes have a significant effect on the glass transition temperatures of these polymers which range from 245 to over 420°C. In contrast, the low temperature dielectric relaxation behavior of these polymers is very similar and is attributed to cooperative local oscillatory—librational motions. Changes in the stereochemistry effect the amplitude, activation energy for the relaxation process, the packing chain density, and values of the high frequency limiting permittivity, ε_∞′. This latter parameter is sensitive to the extent of dipole induced dipole and π‐π electron interactions and is influenced by the packing density. The magnitude of ε_∞′ is a very important parameter in determining the suitability of poly(imide)s for electrical applications. The magnitude of ε_∞′ increases with the density; however, deviations from this general trend are observed when large nonpolar groups inhibit the interaction of neighboring chains. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41191.     

High-Performance Work Systems and Organizational Performance in Emerging Economies: Evidence from MNEs in Turkey

This study examines the association between the usage of high-performance work systems (HPWS) by subsidiaries of multinational enterprises (MNEs) in Turkey and employee and subsidiary level outcomes. The study is based on a survey of 148 MNE subsidiaries operating in Turkey. The results show that the usage of HPWS has a significant positive impact on employee effectiveness. However, their impact on employee skills and development, and organizational financial performance are far less clear. Our findings highlight the extent to which HWPS need to be adapted to take account of context-specific institutional realities.