Accretion onto a compact object must occur through a disc when the material has some initial angular momentum. Thin discs and the thicker low radiative efficiency accretion flows (LRAFs) are solutions to this problem that have been widely studied and applied. This is an introduction to these accretion flows within the context of X-ray binaries and cataclysmic variables. Accretion describes the ...

We address the puzzling observational indications for very "cold" galactic discs at redshifts $z \gtrsim 3$, an epoch when are expected to be highly perturbed. Using a high-resolution cosmological zoom-in simulation, we identify such cold disc $z\sim 3.5$, with rotation velocity dispersion ratio of $v_\phi/\sigma_r \simeq 5$ total gas. It forms as result period intense accretion co-planar, co-r...

At low pressure, ethylene gas consists of single translating and rotating molecules and behaves as an ideal gas. With decrease of free volume by compression, various rotating supramolecular particles are formed, which require less space for the movement: molecular pairs, bimolecules and oligomolecules. The appearance of a new kind of particles is manifested as a phase transition of the second o...

With the development of highly-deviated well cementing techniques, rotating casing cementing technology has got more and more attention. The rotating casing technique can improve the displacement efficiency of cement paste, and then enhance the quality of well cementation. In the stuck section, the rotating casing can redress the well to make the casing run sequentially. The casing endures shea...

Protoplanetary discs (PPDs) are cold, dense and weakly ionised environments that witness the planetary formation. Among these discs, transition (TDs) characterised by a wide cavity in dust gas distribution. Despite this lack of material, many TDs strongly accrete onto their central star, possibly indicating mechanism is driving fast accretion cavities. The presence radially extended 'dead zones...