OPEC's push into refining Dilemma of interactions between crude and product markets

This article shows that the interaction between the crude oil and the product market is not a symmetric phenomenon. A $1.00 change in the price of crude will change the price of the product by only $0.51 (in the short run), while a $1.00 change in the price of refined product will cause a $1.03 change in the price of crude (again, in the short run). The product market is much more sensitive to excess supply than the crude market. Excess supply in the product market will not only depress the price of refined oil, but will also lower the price of crude, with a more significant proportion. At present, the international oil market attempts to avoid the consequences of excess supply in the product market by some sort of subjective coordination of refining capacity utilization. The expected market, however, may change the picture for everyone in the industry — refiners, crude producers and OPEC.     

Transient scattering of elastic waves by three dimensional non-axisymmetric dipping layers

Scattering of elastic plane waves by three dimensional non-axisymmetric multiple dipping layers embedded in an elastic half-space is investigated by using a boundary method. The dipping layer is subjected to incident Rayleigh waves and oblique incident SH, SV and P waves. For the steady state problem, spherical wave functions are used to express the unkown scattered field. These functions satisfy the equation of motion and radiation conditions at infinity but they do not satisfy the stress free boundary conditions on the surface of the half-space. The boundary and continuity conditions are imposed locally in the least-square sense at points on the layer interfaces and on the surface of the half-space. The transient response is constructed from the steady state solution by using Fourier synthesis. Numerical results are presented for both steady state and transient problems. Steady state problems include solutions for two non-axisymmetric dipping layers in the form of a prolate. Transient responses are presented for one and two dipping layer models subjected to incident wave signals in the shape of a Ricker wavelet. It is shown that change in azimuthal orientation of the incident wave may significantly change the surface response of the dipping layer. For the transient problem, response comparison of one and two dipping layers indicates that the addition of an extra layer may also completely change the response characteristics of the alluvium. In particular, the delay in arrival of much larger amplitude surface waves by two dipping layers in comparison with other geometrically compatible models demonstrates the importance of the detailed three dimensional modelling of layered irregularities.     

Behavioral effects of a noisy environment: Task involvement versus passive exposure.

Compared the effects of noise under active task involvement as opposed to passive exposure, using 80 undergraduate Ss who were assigned to 1 of 4 conditions representing 2 * 2 combinations of task vs no task and noise vs quiet. Performance on a dial-monitoring task was unaffected by noise. Ratings of interest and tenseness were significantly higher under the task condition; tenseness was also higher under noise. On a posttest of resistance to frustration, both noise groups, regardless of task condition, showed a smaller degree of persistence on insoluble puzzles than the no-noise groups. Results suggest that aftereffects of noise are not dependent on the power of noise to disrupt task performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Heats of sublimation of nitramines based on simple parameters

In this work, a simple procedure is introduced to determine heats of sublimation of nitramines as an important class of explosives. Molecular weight and one structural parameter of nitramines would be needed in the new method. Calculated heats of sublimation for well-known explosives such as HMX [1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane], RDX [1,3,5-trinitro-1,3,5-triazacyclohexane] and TETRYL [1-(methylnitramino)-2,4,6-trinitrobenzene] as well as new nitramines CL-20 [2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane] and TNAZ [1,3,3-trinitroazatidine] show good agreement with experimental data. R-squared value or the coefficient of determination of new correlation is 0.945. The root-mean-square deviation (RMS) from experiment for the predicted heats of sublimation by new method is 10.10 kJ/mol.     

Modeling Electronic Properties of Multiwall Carbon Nanotubes

Reviewing experimental results and based on the physical reasoning, we present a basic circuit model for Multiwall carbon nanotubes (MWCNTs), which can simulate different experimental results. Investigation of different results confirms the severe effects of fabrication process (nanotube and contacts) on electronic properties of the MWCNTs. The circuit model has been developed to show the performance improvements of a CNT interconnect when the single-wall carbon nanotube (SWCNT) is replaced by an MWCNT. To calculate the current-voltage characteristic and the switching delay of MWCNTs, we have simulated their DC and AC properties, respectively, using the developed transmission line models. Based on the physical models, the elements of the circuit model can be changed so that the simulation and the practical measurements for an MWCNT can correspond. Switching Delays of the MWCNTs and SWCNTs are calculated and compared for different cases.     

Ultra-low-power carbon nanotube FET-based quaternary logic gates

This paper presents low-power carbon nanotube field-effect transistor (CNTFET)-based quaternary logic circuits. The proposed quaternary circuits are designed based on the CNTFET unique properties, such as the same carrier mobility for N- and P-type devices and also providing desirable threshold voltages by adopting proper diameters for the nanotubes. In addition, no paths exist between supply and ground rails in the steady states of the proposed designs, which eliminates the ON state static current and also the stacking technique is utilised in order to significantly reduce the leakage currents. The results of the simulations, conducted using Synopsys HSPICE with the standard 32 nm CNTFET technology, confirm the significantly lower power consumption, higher energy efficiency and lower sensitivity to process variation of the proposed designs compared to the state-of-the-art quaternary logic circuits. The proposed quaternary logic circuits have on average 92, 99 and 91% less total power, static power and PDP, respectively, compared with the most low-power and energy-efficient CNTFET-based quaternary logic circuits, recently presented in the literature.     

Linear and nonlinear melt‐state viscoelastic properties of polypropylene/organoclay nanocomposites

Rheological behavior of polypropylene (PP)/organoclay nanocomposites varying in compatibilizer (PP‐g‐MA) and organoclay concentration was investigated. The samples were prepared by melt intercalation method in an internal mixer. The wide angle X‐ray diffraction patterns and results of rheological measurements showed that the compatibilizer had strong influence in increasing the interlayer spacing. The observed low frequency liquid‐like to solid‐like transition and apparent yield stress in simple shear flows, along with convergence of transient shear stress to nonzero values in stress relaxation after the cessation of flow experiments, were found to be consistent with formation of a physical network in quiescent conditions which could be easily ruptured with applying low shear rates. The values of stress overshoot strain in flow reversal experiments were independent of shear rate, organoclay, and compatibilizer content. From the results of frequency sweep experiments in different nonlinear strain amplitudes it was shown that extended Cox‐Merz analogy was valid in nonlinear dynamic deformations while the shear viscosity showed positive deviation from this analogy with higher deviations at lower shear rates. Results of storage modulus recovery and flow reversal experiments at different shear rates suggested that network structure is reformed with a much slower rate compared to the rotational relaxation of organoclay platelets. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers     

Analysis of energy consumption in Finland based on the selected economics indicators

Energy is one of the main inputs of productions. Therefore, national policies have emphasised on accessibility, availability, and affordability of energy supply. This is very important for energy importers, in particular countries with high dependency on industrial products. Finland is one of such countries that has high-energy consumption due to its cold climate, energy-intensive industries, and low population density. Therefore, security of energy supply to respond domestic consumption is one of the main concerns of the Finnish government. To have a resilience energy supply, it is necessary to understand the energy system in Finland. Energy modelling is a tool that helps policy-makers and researchers to understand the fluctuations and changes in the energy system. This research is to investigate the relationship between energy consumption and selected macro-economic factors in Finland. Therefore, energy consumption in each sector is analysed and the importance of renewable energies is also considered. Finally, a regression model is presented to predict energy consumption.