There are two proposed explanations for ultraluminous X-ray sources (ULXs) with luminosities in excess of 10(39) erg s(-1). They could be intermediate-mass black holes (more than 100-1,000 solar masses, M sun symbol) radiating at sub-maximal (sub-Eddington) rates, as in Galactic black-hole X-ray binaries but with larger, cooler accretion disks. Alternatively, they could be stellar-mass black holes radiating at Eddington or super-Eddington rates. On its discovery, M 101 ULX-1 had a luminosity of 3 × 10(39) erg s(-1) and a supersoft thermal disk spectrum with an exceptionally low temperature--uncomplicated by photons energized by a corona of hot electrons--more consistent with the expected appearance of an accreting intermediate-mass black hole. Here we report optical spectroscopic monitoring of M 101 ULX-1. We confirm the previous suggestion that the system contains a Wolf-Rayet star, and reveal that the orbital period is 8.2 days. The black hole has a minimum mass of 5 M sun symbol, and more probably a mass of 20 M sun symbol-30 M sun symbol, but we argue that it is very unlikely to be an intermediate-mass black hole. Therefore, its exceptionally soft spectra at high Eddington ratios violate the expectations for accretion onto stellar-mass black holes. Accretion must occur from captured stellar wind, which has hitherto been thought to be so inefficient that it could not power an ultraluminous source.

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The vibration-stress field could be formed by high vibration intensity in vibration machine to improve the ability of the collision, shock, shear and extrusion for the system, and it also can avoid plugging screen for vibration screening machine, which could make for solving some special requirements of the vibration machine. To research the vibration machines strongly nonlinear and high vibration intensity characteristic such as certain excitation and uncertain response, the vibration machine with its double-mass is built, and its vibration exciter uses two partial blocks as vibration motor. In addition, dynamic vibration differential equation is established. To achieve high vibration intensity results based on the vibration machines safe working, the advanced control based on the SCM and Intelligent frequency conversion is put forward, and the advanced control system with its host computer, frequency converter, SCM, charge-amplifier, sensor and the vibration machine is been established.