Fractional grey model based on non-singular exponential kernel and its application in the prediction of electronic waste precious metal content

2020 ◽  
Vol 107 ◽  
pp. 12-26 ◽  
Author(s):  
Shuhua Mao ◽  
Yuxiao Kang ◽  
Yonghong Zhang ◽  
Xinping Xiao ◽  
Huimin Zhu
Author(s):  
Dario Nappo

This chapter considers the financial scale of Indo-Roman trade via the Red Sea, comparing the large sums mentioned by Pliny with the evidence of customs dues, ostraca from the Red Sea port of Berenike, and hoards of Roman coins found in India. Analysis of the finds of Roman coins in India by value rather than number over time suggests that, contrary to prevailing opinion, there was not a major diminution in the value of the trade after the reign of Tiberius. Although there was apparently some decline in the Flavian period, the face value of coin finds recovers in the second century until the reign of Antoninus Pius. Coins for export to India were specially selected for their higher precious metal content, and older issues with a higher silver content continued to be exported to India long after they had largely ceased to circulate within the Roman Mediterranean.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
José A. Zamora Zeledón ◽  
Michaela Burke Stevens ◽  
G. T. Kasun Kalhara Gunasooriya ◽  
Alessandro Gallo ◽  
Alan T. Landers ◽  
...  

AbstractAlloying is a powerful tool that can improve the electrocatalytic performance and viability of diverse electrochemical renewable energy technologies. Herein, we enhance the activity of Pd-based electrocatalysts via Ag-Pd alloying while simultaneously lowering precious metal content in a broad-range compositional study focusing on highly comparable Ag-Pd thin films synthesized systematically via electron-beam physical vapor co-deposition. Cyclic voltammetry in 0.1 M KOH shows enhancements across a wide range of alloys; even slight alloying with Ag (e.g. Ag0.1Pd0.9) leads to intrinsic activity enhancements up to 5-fold at 0.9 V vs. RHE compared to pure Pd. Based on density functional theory and x-ray absorption, we hypothesize that these enhancements arise mainly from ligand effects that optimize adsorbate–metal binding energies with enhanced Ag-Pd hybridization. This work shows the versatility of coupled experimental-theoretical methods in designing materials with specific and tunable properties and aids the development of highly active electrocatalysts with decreased precious-metal content.


Author(s):  
Ian Proops

The book aims to provide a comprehensive study of the ‘Transcendental Dialectic’ of Kant’s first Critique. It argues that Kant conceives of ‘critique’ as a kind of winnowing exercise, aimed to separate the wheat of good metaphysics from the chaff of bad. However, he uses a less familiar metaphor to make this point, namely, that of ‘the fiery test of critique’. This turns out to be, not a medieval ordeal (a trial by fire), but rather a metallurgical assay: so-called ‘cupellation’—a procedure in which ore samples are tested for their precious-metal content. The upshot is that critique has a positive, investigatory side: it seeks not merely to eliminate the dross of bad ‘dogmatic’ metaphysics but also to uncover any hidden nuggets of value that might be contained in traditional speculative metaphysics. There are both gold and silver to be found. The gold is the indirect proof of Transcendental Idealism afforded by the resolution of the Antinomies, the silver Kant’s defence of theoretically grounded ‘doctrinal beliefs’ in a wise and great originator and in an afterlife. In the course of making these points, the book engages with Kant’s views on a number of central problems in philosophy and meta-philosophy, including: the explanation of the enduring human impulse towards metaphysics, correct philosophical method, the limits of self-knowledge, the possibility of human freedom, the resolution of metaphysical paradox (‘Antinomy’), the justification of faith, the nature of scepticism, and the role of ‘as if’ reasoning in natural science.


2021 ◽  
pp. 65-72
Author(s):  
T. T. Meem ◽  
M. S. Khan ◽  
M. M. Hassan ◽  
R. Mamtaz

2011 ◽  
Vol 88 (2-3) ◽  
pp. 83-100 ◽  
Author(s):  
P.K. Prachiti ◽  
C. Manikyamba ◽  
Prakash K. Singh ◽  
V. Balaram ◽  
G. Lakshminarayana ◽  
...  

BDJ ◽  
1988 ◽  
Vol 165 (4) ◽  
pp. 118-119
Author(s):  
C H Turner ◽  
A F Willoughby

2009 ◽  
Vol 1209 ◽  
Author(s):  
Maximilian Albert Biberger ◽  
D. Leamon ◽  
X. Qi ◽  
R. Sawayda ◽  
Q. Yin

AbstractIn the present paper a novel method of manufacturing mobile emission control catalysts (MECC) is presented. The manufacturing of these novel catalysts consists of three steps: In a first processing step micron sized powders consisting of an oxide powder, typically Al2O3 or SiO2 or the like, and micron sized precious metal powders, Pt, Pd, Rh or the like, are co-fed into a DC plasma gun. Inside the gun the powders are vaporized at temperatures of approximately 25,000 K. After the powders are vaporized the vapor is rapidly quenched at rates of approximately 1,000,000 K/s. This process step yields so-called Nano on Nano Catalysts™, where nano clusters of precious metals atoms are condensed onto the nano sized oxide particles. In a second processing step these Nano on Nano Catalysts™ are dispersed in water. This step is followed by a third, and final processing step, where the Nano on Nano Catalysts™ are integrated onto the final support, i.e. the monoliths (or honeycombs), which ultimately are canned and located downstream of a vehicle’s engine. Catalysts manufactured under the above conditions are then tested against reference catalysts, both under fresh and aged conditions. Test results show that the plasma based catalysts have better light off temperatures after aging than the reference catalysts if they contain the same amount of precious metals as the reference catalyst. If the precious metal amount for the plasma based catalysts is reduced to approx. half the amount of the reference catalysts then both catalysts show approx. the same light off temperatures after aging. Above results show that with catalysts based on plasma technology one can either lower the light off temperatures while maintaining the precious metal content compared to reference catalysts, or match the performance of the reference catalysts while reducing the precious metal content to approx. 50%, compared to the reference catalysts.


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