Running a crude vacuum tower in a deep cut mode can provide economic and operational benefits to the refiner. Fully evaluating these benefits usually requires an engineering study. Crude type, furnace, tower, exchanger and vacuum jet equipment all play important roles in the ultimate capacity, low-pressure capability and revamp cost of each specific unit. However, a simplified analysis can bene...

Magnetic strings are defined as infinitely thin surfaces which are closed in the vacuum and can be open on an external monopole trajectory (that is, defined by 't Hooft loop). We review briefly lattice data on the magnetic strings which refer mostly to SU(2) and SU(3) pure Yang-Mills theories and concentrate on implications of the strings for the Yang-Mills plasma. We argue that magnetic string...

Medium-induced gluon radiation is usually identified as the dominant dynamical mechanism underling the jet quenching phenomenon observed in heavy-ion collisions. In its actual implementation, multiple medium-induced gluon emissions are assumed to be independent, leading, in the eikonal approximation, to a Poisson distribution. Here, we introduce a medium term in the splitting probabilities so t...

Next-to-next-to-leading order vacuum polarization function of heavy quark near threshold and sum rules for b ¯ b system. Abstract A correlator of the vector current of a heavy quark is computed analytically near threshold in the next-to-next-to-leading order in perturbative and relativistic expansion that includes α 2 s , α s v and v 2 corrections in the coupling constant and velocity of the he...

Collisions between heavy nuclei at the Relativistic Heavy Ion Collider liberate from the nuclear wavefunction of order 10,000 gluons, quarks and antiquarks. The system is dominated by gluons and up and down (anti) quarks. Heavy quarks, though having little effect on the overall equation of state, are critical as probes of the surrounding medium. We compare predictions from a scenario where the ...

We have performed a vacuum ultraviolet laser excited photoemission spectroscopy on a d-electron heavy-fermion-like material LiV2O4 single crystal. We observed a sharp peak structure in the density of states at approximately 4 meV above the Fermi level (E(F)). The evolution of the peak height corresponds well with the crossover behavior to the heavy-fermion-like state as observed in the thermal ...

We calculate the minimal energy path over the sphaleron barrier in the presence of fermions, assuming that the fermions of a doublet are degenerate in mass. This allows for spherically symmetric ansätze for the fields, when the mixing angle dependence is neglected. While light fermions have little influence on the barrier, the presence of heavy fermions (MF ∼ TeV) strongly deforms the barrier, ...

Vacuum grippers are often notably diffused for grasping and moving very large and heavy objects. The absence of theoretical models able to foresee the behavior of the suction cup notably limits the applications and development of vacuum grippers. In this work, a study of grasping with a vacuum gripper has been carried out. A mathematical model is proposed for determining the forces of contact b...