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A normalized hot forged Cu-15Zn-6Al (mass. %) shape memory alloy (SMA) was subjected to tempering heat treatments meant to enhance the reversion to parent phase (austenite) of thermally induced martensite. By means of differential scanning calorimetry (DSC) the reversibility of martensitic transformation was verified during constant-rate heating-cooling cycles. The results have showed that 373 K- tempering destabilized martensite and enabled its
Read moreTemperature memory effect (TME) is usually manifested by a kinetic stop during reverse transformation of thermally induced martensite to parent phase, after performing an incomplete heating in the previous thermal cycle, applied to a shape memory alloy (SMA). Technically TME causes the splitting of the endothermic peak corresponding to martensite reversion, on differential scanning calorimetry (DSC) thermograms. The present paper illustrates new
Read moreA major part of the computational effort in chemical process simulation and compositional reservoir simulation is spent by phase equilibrium calculations: phase split and phase stability analysis. The calculation algorithms must be efficient and highly robust. The reduction methods offer an attractive alternative to conventional methods. Several recent papers have questioned on the efficiency of the reduction methods as compared to conventional methods,
Read moreIn this work, a new method is proposed for solving Underwood's equations. Newton methods cannot be used without interval control, and may require many iterations or experience severe convergence problems if the roots are near poles and the initial guess is poor. It is shown that removing only one adjacent asymptote leads to convex functions, while removing both asymptotes leads to quasi convex functions which are close to linearity on wide intervals.
Read morepH affects both soil–water partitioning coefficient (Kd) of polychlorinated biphenyls (PCBs) and dissolved organic matter (DOM), thereby influencing PCBs' leachability from contaminated soils. To explore these incompletely understood interactions, the leachability of 11 selected PCBs in a naturally aged soil was investigated in pH static leaching tests spanning a wide pH range (2 to 9). The Kd was calculated for each of the PCBs, based on their
Read moreThe influence of soil composition (peat and clay content) on the leachability was investigated in batch leaching experiments for chemically diverse hydrophobic organic compounds (HOCs: PCP, PAHs, HCB, HCHs, PCBs, and TCDD/Fs). An experimental design was applied to generate 8 diverse soil matrices, and the results were evaluated by orthogonal projections to latent structures (OPLS), as well as compound specific response surface models. Overall, the
Read moreThis paper addresses a pressing current topic on the International Monetary System (IMS) and the need for its fundamental reform. In principle, at present, this need for reform is agreed by all specialists and more and more of those who govern the world's countries. The paper presents the main vulnerabilities of SMI, some aspects of his background, a review of several papers, a brief critical analysis of IMS and some proposals and conclusions which
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