A lubricating oil composition for fluid dynamic bearings which comprises 50 to 100% by mass of an ether compound comprising at least one ether bond and having 11 to 34 carbon atoms as the base oil and has a kinematic viscosity of at least 2.2 mm
2
/s at 100° C. is provided. The composition has excellent viscosity characteristics such as excellent fluidity at low temperatures and a small decrease in the viscosity in a high temperature range, exhibits lower evaporability, excellent energy saving property and excellent heat stability and is advantageously used for compact fluid dynamic bearings used under rotation at a high speed.
A method for manufacturing polycarbonate by melt-polycondensing bisphenol and carbonic acid diester uses as catalyst an alkali metal compound and/or alkaline earth metal compound (a). The catalyst is added to the bisphenol prior to the melt polycondensation, in an effective amount, i.e., the amount of alkali metal compound and/or alkaline earth metal compound (a) that acts effectively as a catalyst, is contained in said bisphenol, and is controlled to have the same catalytic activity as 1×10
−8
to 1×10
−6
mole of bisphenol disodium salt per mole of pure bisphenol A. The method conducts the reaction efficiently from the initial stage in a stable manner to obtain polycarbonate with good color, good heat stability and color stability during molding and the like.
Trialkylphosphates are synthesized from alcohols by reaction with reactive phosphorus oxychloride under microwave irradiations and classical heating. Effects of these irradiations on the nature of the products and on the yield are studied. The compounds were characterized by their spectroscopic data and elemental analysis. The obtained results show that the products of these reactions are essentially trialkylphosphates and alkylphosphoric acids. They always show as the nature of the formed products and the yields in trialkylphosphates are comparable to those obtained in the classical conditions of heating. The speed of the reaction was increased by a factor from 40 to 120.
[EN] PROCESS FOR REMOVAL OF ACID GASES FROM A FLUID STREAM<br/>[FR] PROCÉDÉ D'ÉLIMINATION DE GAZ ACIDES CONTENUS DANS UN COURANT DE FLUIDE
申请人:BASF SE
公开号:WO2021047928A1
公开(公告)日:2021-03-18
A process for removing acid gases from a fluid stream, wherein the fluid stream is contacted with an absorbent to obtain a treated fluid stream and a laden absorbent, the absorbent comprising at least one diluent and a compound of the general formula (I) wherein R1 is C1-C3-alkyl; R2 is C1-C3-alkyl; R3 is selected from hydrogen and C1-C3-alkyl; R4 is selected from hydrogen and C1-C3-alkyl and n is an integer in the range of 1 to 4.