Adoption of carbon dioxide efficient technologies and practices: An analysis of sector-specific convergence trends among 12 nations

Carbon dioxide intensities in economic terms (GDP in PPP terms) in industrialized and developing countries have been shown to converge, and it has been argued that technology diffusion, leading to the use of similar technologies in all countries, is an important reason for this convergence. Indicators based on CO₂ per output in PPP terms, however, give in comparison to physical indicators limited understanding of the process of technology diffusion. In order to analyze the technology diffusion hypothesis in more detail, we therefore study the trend in carbon dioxide emissions in relation to the production output in four separate sectors: iron and steel; paper, board and pulp; coal fuelled power plants; and natural gas fuelled power plants, in each of 12 countries, between 1980 and 1998. The indicators converge in each sector, indicating that across countries, technologies with more similar carbon dioxide efficiencies are used today than 25 years ago. We also find that at least some developing countries with high energy prices use more efficient technologies than industrialized countries with low energy prices.     

Local RBF‐FD solutions for steady convection–diffusion problems

This paper describes the application of radial basis function (RBF) based finite difference type scheme (RBF‐FD) for solving steady convection–diffusion equations. Numerical studies are made using multiquadric (MQ) RBF. By varying the shape parameter in MQ, the accuracy of the solution is seen to be highly improved for large values of Reynolds' numbers. The developed scheme has been compared with the corresponding finite difference scheme and found that the solutions obtained using the former are non‐oscillatory. Copyright © 2007 John Wiley & Sons, Ltd.     

Sodium transport in polyimide-SiO2 systems

The use of polyimide (PI) in integrated circuits either as a passivant or as an interlevel dielectric requires an understanding of the potential for transfer of contaminant ions, always present to some degree in device-grade PI, from the PI to other device constituents. Sodium, in particular, if transferred from PI to SiO₂ where it is relatively mobile at typical device operating temperatures, could affect device thresholds and create a reliability problem. In this paper, the quasistatic Q-V technique of Brown using metal-PI-SiO₂-Si structures has been applied to the quantitative study of the transfer of Na between PI and SiO₂. Removal of the PI after cure or after application of bias-temperature stress has been used to demonstrate that (1) quantitative, reversible ion transfer between PI and SiO₂ does occur at temperatures above 200°C in the presence of an applied bias, but (2) in the absence of an applied bias, Na ions are not transferred from PI to SiO₂ during PI cure at 350°C. It is also shown that the kinetics of Na transfer from PI to SiO₂ in the presence of a bias are dominated by an activated diffusion process, with an activation energy on the order of 2.0eV and a prefactor on the order of 2x10⁹ cm²/s.     

Transport properties of fluids near critical points

The paper reviews the theoretical and experimental results for the asymptotic behavior of the dynamics of critical fluctuations in fluids and fluid mixtures near a critical point. The implications of these results for the development of accurate representative equations for the viscosity and thermal conductivity of gases in the critical region are discussed.Invited lecture presented at the 10th International Conference on the Properties of Steam, Moscow, USSR, September 2–7, 1984.     

Long-term iceberg collision-risk assessment methods for fixed offshore structures

This study shows that iceberg collision-risks for fixed offshore structures in the Arctic are often heavily underestimated at present. The study concentrates on concepts for the mathematical modelling of the probability of an iceberg hitting a fixed offshore structure in the Arctic. Simple and verifiable assumptions provide extensive statements of this risk. A fractal model for iceberg production is used. An iceberg melting and breakdown model is formulated and its risk implications are derived by analysing iceberg tracks by geometrical methods. Some numerical results from data analyses and simulations are presented. This work is intended to be a contribution to the discussion on ‘engineering standards’ and indicate where attention is required when carrying out data acquisition programs in the Arctic.     

硅中离子注入硼的异常扩散

本工作用不同的Si~+预注入能量,改变注入损伤分布与离子注入硼杂质分布的相对位置,观察快速热退火中注入损伤对硼异常扩散的影响.结果表明,引起注入硼异常扩散的是点缺陷,而不是硼间隙原子的快扩散.而注入损伤中的点缺陷和簇团分解释放的点缺陷是驱动硼异常扩散的因素之一.如果注入损伤形成了扩展缺陷,那么扩展缺陷重构和分解将发射点缺陷,这是驱动硼异常扩散的另一个因素.     

Accurate transport properties and second virial coefficients for helium based on a state-of-the art interatomic potential

Second virial coefficients and transport properties of helium are presented based on a state-of-the-art interatomic potential which was constructed with the use of a multiproperty fit. The experimental potential employed to produce these properties accurately reproduces a wide range of bulk and microscopic data and agrees well with ab initio calculations which were not available at the time of its construction. Virial coefficients of ³He and ⁴He are presented from 2 to 600 K, and transport properties of pure ³He and ⁴He gases and ³He-⁴He mixtures are presented from 5 to 6000 K.     

Thermopower measurements on BiSrCaCuO system

We report thermoelectric power measurements on BiSrCaCuO (2212) superconducting oxide and compare the observed behaviour with that of the YBaCuO (123) system. The relative importance of phonon drag and diffusion thermopower contributions is evaluated for the two systems by analysing the data using a generalized expression of the typeS=αT+β/T. The thermopower enhancement effect just aboveT _c gives parameter values comparable to those of YBa₂Cu₃O_7−x system.     

Calculation of solute-vacancy binding energy in dilute fcc and bcc alloys by diffusion

Due to excess charge of the solute with respect to solvent, the free energy of vacancy formation and migration in the neighbourhood of the solute will change. This results in a change in the solvent diffusivity. A relation for the solute vacancy binding energy for fcc and bcc lattices using enhancement factor has been derived considering the solute vacancy interactions to be limited to first neighbour and neglecting the changes in the solvent correlation factor.     

A computer simulation of LiKSO4

Molecular-dynamics computer-simulation of an ionic molecular solid LiKSO₄ has been carried out at 300 and 1000 K using the atom-atom potentials obtained from lattice dynamical studies. We observe hopping of lithium ions to interstitial positions which is related to reorientations of sulphate tetrahedra.