People and Urban Renaissance

Industrial ecology is an evocative metaphor that has evolved into a new paradigm for environmental management. It locates human activity in a larger, environmental context and uses the natural world as a model for organizing industrial activities. To date the concepts of place and jurisdiction have been missing from industrial ecology, even though many important environmental decisions are made within local political boundaries. Planners are uniquely equipped to advance this field because they (a) study locally-open systems such as economies, and (b) link big-picture ideas to incremental decisions. In return, industrial ecology offers planners an integrative framework for describing, explaining, and solving environmental problems.     

Fracture characteristics of high impact polystyrene under impact fatigue loadings

This study analyses the impact properties of high impact polystyrene (HIPS). HIPS is one of the well-known toughened polymers. The high toughness is given by the rubbery phase. The impact fatigue behavior of HIPS was studied with a Ceast pendulum type tester (Resil 25). The fracture mechanisms were examined with a scanning electron microscopy. The nature of crack initiation and propagation was investigated for small impact angles and three different spans. The impact angles of charpy hammer were chosen as 5°, 10°, 15°, 20°, and 25°. The fracture characteristics varied with the impact angle, the number of impacts, and the distance between supports. The rate of crack propagation was high at higher impact angles with lower endurance, and low at lower impact angles with higher endurance.     

Ab initio and DFT study on 1,4-dinitroglycoluril configurational isomers: cis-DINGU and trans-DINGU

cis-1,4-Dinitroglycoluril (1,4-dinitrotetrahydroimidazo[4,5-d]imidazole-2,5-(1H,3H)-dione, C(4)H(4)N(6)O(6), known as DINGU in the literature) is an important explosive regarded as one of the potential ingredients for LOVA (low vulnerability ammunition) applications. However, there is no study concerning trans-DINGU, to the best of our knowledge. Thus, in the present study the structural and electronic properties of the configurational isomers of DINGU (cis- and trans-isomers) have been investigated by performing density functional theory (DFT) calculations at B3LYP/6-31G(d,p), UB3LYP/6-31G(d,p) levels and also ab initio calculations at RHF/6-31G(d,p) and UHF/6-31G(d,p) levels. The optimized geometries, vibrational frequencies, electronic structures, and some thermodynamical values for the presently considered DINGU isomers have been obtained in their ground states. Comparing the calculated energy data (total electronic energy, heat of formation values and homolytic bond dissociation values of N-NO(2)) and the calculated bond lengths, cis-DINGU was found to be a more stable molecule than the trans-isomer.     

Fabrication of calix[4]pyrrole nanofilms at the glassy carbon surface and their characterization by spectroscopic, optic and electrochemical methods

meso-Octamethylcalix[4]pyrrole (CP) and meso-heptaethylcalix[4]pyrrole-meso-4-aminophenyl (4APCP) modified glassy carbon (GC) electrodes were prepared by the electrochemical oxidation in acetonitrile solution. Binding of the calix[4]pyrroles with the glassy carbon surface was investigated that it is through the etheric linkage revealed from the reflection-absorption infrared spectroscopy (RAIRS). Surface films of CP and 4APCP were investigated by cyclic voltammetry (CV), ellipsometry, X-ray photoelectron spectroscopy, RAIRS and the contact angle measurements. The thicknesses of the films were determined by ellipsometry which confirmed that the film was multilayer and homogeneous over the surface. Ellipsometric measurements also provided that the CP and 4APCP film thicknesses were 2.49 nm and 4.58 nm for 6 CV cycle modification, corresponding to 66 μF/cm² and 106 μF/cm² capacitances obtained by CV. The wetting behavior was examined by contact angle measurements and found that the hydrophobicity of the GC-4APCP surface was higher than that of GC-CP, probably due to the aromatic meso substituent present in the former.     

Minimizing L max for the single machine scheduling problem with family set-ups

A procedure for the single machine-scheduling problem of minimizing the maximum lateness for jobs with sequence independent set-ups is presented. The procedure provides optimal/near-optimal solutions over a wide range of problems. It performs well compared with other heuristics, and it is effective in finding solutions for large problems.     

CHEMICAL CHARACTERISTICS OF SUPERCRITICAL TOLUENE EXTRACTS FROM TWO TURKISH LIGNITES

Samples from two major deposits of Turkish lignites were subjected to supercritical toluene extraction at 325°C and 14.1 MPa in an autoclave. The resultant extracts were separated into pre-asphaltene, asphaltene, saturates, aromatics and resin fractions by column chromatography. The fractions were characterized by ¹H-NMR, ¹³C-NMR, IR. and elemental analysis in order to compare the chemical composition of extracis from the two coal samples. The results show that the extracts from the Tungbiiek (T-coal) deposits contain aliphatic constituent which is composed of mostly long chain unbranched alkyl compounds while the extracts from the Soma Mcrkeg (S-coal) deposits contain a significant amount of branched paraffinic compounds. The resin fractions from both samples were found to contain a significant amount of single ring aromatic compounds.     

PETROLEUM AT THE ROOF OF THE WORLD: The geological evolution of the Tibet (Qinghai-Xizang) Plateau Part I

The Tibet (Qinghai-Xizang) Plateau is underlain by many thousands of mters of Ordovician (and possibly Cambrian) through Middle Eocene, gently-dipping, essentially undeformed, stable platform sequences. These are largely qf shallow-water, marine-shelf origin in the Ordovician-Triassic sections, but are of mixed continental and marine facies in the Jurassic through Midle Eocene sections. Two east-west fault troughs - the Banggong Co - Nu Jianand Indus River -Yarlung Zangbo - contain thick sections of Triassic, Jurassic, and/or Cretaceous marine flysch associated with ophiolites. The only severe deformation to affect the plateau was during the Mesozoic, and it was concentrated close to the through-going east-west fractures. Post-early Eocene beds are entirely continental, and are concentrated nsmall-to-large grabens. One of these, the Lunpola Basin, has been moderately explored. Drilling here during the 1970s recovered small amounts of heavy, biodegraded oil of non-marine origin, from a sectionthat ranges in age from Middle Eocene through Quaternary Plateau-wide stratigraphic studies reveal that the Ordovician through Early Carboniferous, and Late Permian through Middle Eocene, sections were deposited on a monolithic stable block. All were deposited in essentially warm tropical seas in close proximity, as demonstrated by the, facies, faunas, and floras. These same studies, plus related tectonic investigations, reveal that the through-going east-west fracture zones, popularly interpreted as “sutures,” are not sutures at all. Rather, the facies belts in rocks of all ages studied in detail routinely cross the so-called “sutures,” commonly at very sharp angles, proving that these east-west fault zones exerted no control overthe general lithofacies deposition patterns of the Himalaya-Tibet block. The oniy facies control exerted by the fracture zones was in the small, narrow troughs that developed along them. Thus, the Himalaya-Tibet block behaved as a single structural unit through time, and was never segmen red in to various microcontinents. Although some potential for commercial petroleum discoveries exists in the post-middleEocene grabens. the greatest potential of the Himalaya-Tibet block is in the Paleozoic-Mesozoicsection. with its promise of multiple source-beds. reservoirs, traps, and seals. We predict that, one day, this “roof of the world” will host many petroleum Jields.     

Solution-processed LiF for work function tuning in electrode bilayers

Although ambient processing is the key to low-cost organic solar cell production, high-vacuum thermal evaporation of LiF is often a limiting step, motivating the exploration of solution processing of LiF as an alternative electrode interlayer. Submonolayer films are realized with the assistance of polymeric micelle reactors that enable LiF particle deposition with controlled nanoscale surface coverage. Scanning Kelvin probe reveals a work function tunable with nanoparticle coverage with higher values than that of bare indium tin oxide (ITO).