We present the newest results for the determination of heavy-quark masses from low-energy moments of the vacuum polarization function. The results presented here update an earlier determination of the quark masses and incorporate new theoretical calculations of the low-energy moments of the vacuum polarization and new experimental data at the bottom threshold.

This paper summarizes the experience gained over seven years of operating an H-Oil ebullated-bed vacuum residue hydrocracking unit. The following key factors in improving performance process were identified, including feedstock quality, catalyst condition, as well loading and utilization unconverted residue. optimum combination these four allowed a conversion rate about 90% to be achieved. chal...