Abstract: A system and method for preparing epoxy chloropropane is provided in that by coupling three stages of high gravity reactors, the product epoxy chloropropane and water vapor are distilled from a reaction system in form of an azeotrope by adopting a water vapor steam stripping method. Further, by combining the azeotrope with the multiples stages of high gravity reactors, the gas phase mass transfer and the liquid phase mass transfer of the azeotrope are improved aiming at the features of the azeotrope in the reaction system, thus making the overall conversion rate higher. In addition, by combining steam stripping and high gravity, dichloropropanol and alkali solution are rapidly mixed for mass transfer, and the product epoxy chloropropane is rapidly distilled from the reaction system in the form of the azeotrope, such that the reaction proceeds continuously towards the direction of producing epoxy chloropropane, thus significantly improving the conversion rate.

Abstract: Methods and systems are provided for cooling hot spots on a body coil assembly of an MRI system. In one embodiment, an airflow guide of a body coil assembly of an MRI system comprises a first surface that forms an air passage when the airflow guide is positioned on the body coil assembly, the air passage enclosed by the first surface and a second, outer surface of an RF coil of the body coil assembly, the airflow guide configured to channel cool air generated by a fan to the second, outer surface of the RF coil. The airflow guide may be arranged circumferentially around a portion of the RF coil at one or more ends of the RF coil. The airflow guide may be manufactured as a plurality of airflow guide segments that are glued together.

Abstract: A system and method for preparing epoxy chloropropane is provided in that by coupling three stages of high gravity reactors, the product epoxy chloropropane and water vapor are distilled from a reaction system in form of an azeotrope by adopting a water vapor steam stripping method. Further, by combining the azeotrope with the multiples stages of high gravity reactors, the gas phase mass transfer and the liquid phase mass transfer of the azeotrope are improved aiming at the features of the azeotrope in the reaction system, thus making the overall conversion rate higher. In addition, by combining steam stripping and high gravity, dichloropropanol and alkali solution are rapidly mixed for mass transfer, and the product epoxy chloropropane is rapidly distilled from the reaction system in the form of the azeotrope, such that the reaction proceeds continuously towards the direction of producing epoxy chloropropane, thus significantly improving the conversion rate.

Abstract: Methods and systems are provided for cooling hot spots on a body coil assembly of an MRI system. In one embodiment, an airflow guide of a body coil assembly of an MRI system comprises a first surface that forms an air passage when the airflow guide is positioned on the body coil assembly, the air passage enclosed by the first surface and a second, outer surface of an RF coil of the body coil assembly, the airflow guide configured to channel cool air generated by a fan to the second, outer surface of the RF coil. The airflow guide may be arranged circumferentially around a portion of the RF coil at one or more ends of the RF coil. The airflow guide may be manufactured as a plurality of airflow guide segments that are glued together.

Abstract: A magnetic resonance imaging system includes a processor. The processor is configured to acquire a variation of a first system state parameter during a scanning process of the magnetic resonance imaging system, determine, according to the variation of the first system state parameter, a variation of a second system state parameter on the basis of a function relationship between the first system state parameter and the second system state parameter, and correct the magnetic resonance imaging system on the basis of the variation of at least one of the first system state parameter and the second system state parameter.

Abstract: A monitoring method and device for a magnetic resonance imaging system comprises: acquiring a whole body specific absorption rate of a subject under examination; acquiring a ratio between a local region specific absorption rate and the whole body specific absorption rate of the subject under examination on the basis of current parameter information of a local coupling coil in the magnetic resonance imaging system; and calculating the local region specific absorption rate of the subject under examination on the basis of the ratio between the local region specific absorption rate and the whole body specific absorption rate, and the whole body specific absorption rate.

Abstract: The present invention provides a monitoring method and device for a magnetic resonance imaging system, and a magnetic resonance imaging system. The monitoring method comprises: acquiring a whole body specific absorption rate of a subject under examination; acquiring a ratio between a local region specific absorption rate and the whole body specific absorption rate of the subject under examination on the basis of current parameter information of a local coupling coil in the magnetic resonance imaging system; and calculating the local region specific absorption rate of the subject under examination on the basis of the ratio between the local region specific absorption rate and the whole body specific absorption rate, and the whole body specific absorption rate.

Abstract: A method for post-processing a colored zirconium oxide ceramic, the method comprising: putting the colored zirconium oxide ceramic along with a deoxidant into a heating device, conducting a firing process at a preset temperature, and a colorant containing Pr3+ is used for the coloring, and the deoxidant is excessive with respect to a stoichiometric amount of oxygen in the heating device. The technical solution can completely replace Fe3+ with Pr3+ to color the zirconium oxide ceramic yellow.

Abstract: A preparation method of lithium metasilicate glass ceramic, comprises (a) preparing a melt of glass matrix; (b) pouring the melt of glass matrix into a mould, and cooling to obtain a blank of glass matrix; (c) placing the blank of glass matrix in a heating device to carry out heat treatment, the process parameters of which include: heating to a temperature of 450-600° C. under a heating rate of 5-20° C./min, and keeping the temperature for 20-150 min; and cooling along with the heating device to obtain the lithium metasilicate glass ceramic after the heat treatment. Compared with the prior art, in the resulted lithium metasilicate glass ceramic, the main crystal phase of lithium metasilicate exhibits the crystal morphology of sphere which is in nano-size and uniform. The lithium metasilicate glass ceramic is low in crystallization degree, and thus has reduced hardness.

Abstract: A method for post-processing a colored zirconium oxide ceramic, the method comprising: putting the colored zirconium oxide ceramic along with a deoxidant into a heating device, conducting a firing process at a preset temperature, and a colorant containing Pr3+ is used for the coloring, and the deoxidant is excessive with respect to a stoichiometric amount of oxygen in the heating device. The technical solution can completely replace Pe3+ with Pr3+ to color the zirconium oxide ceramic yellow.

Abstract: A coloring solution for dental zirconia ceramics and a method for using the same are provided. The coloring solution consists of coloring agents, a solvent, and an additive. The coloring agents are a combination of two or more rare earth metal compounds, wherein the rare earth metal compounds having rare earth metal ions selected from the group consisting of praseodymium (Pr) ions, erbium (Er) ions, cerium (Ce) ions, and neodymium (Nd) ions. The concentration of the rare earth metal ions in the solution is 0.05˜3 mol/liter solvent. The molar ratio of Pr ions:Er ions:Ce ions:Nd ions in the solution is 1:(10˜50):(0˜20):(0˜30).

Abstract: A coloring solution for dental zirconia ceramics and a method for using the same are provided. The coloring solution consists of coloring agents, a solvent, and an additive. The coloring agents are a combination of two or more rare earth metal compounds, wherein the rare earth metal compounds having rare earth metal ions selected from the group consisting of praseodymium (Pr) ions, erbium (Er) ions, cerium (Ce) ions, and neodymium (Nd) ions. The concentration of the rare earth metal ions in the solution is 0.05˜3 mol/liter solvent. The molar ratio of Pr ions:Er ions:Ce ions:Nd ions in the solution is 1:(10˜50):(0˜20):(0˜30).

Abstract: The present invention relates to a method for changing translucency of zirconia dental materials through applying an yttrium or ytterbium salt solution onto a pre-sintered zirconia material by dipping or brush-coating. Accordingly, the need of young patient in relation to the translucent requirement for incisal portion of anterior teeth is met in which the translucent level from the crown neck to the incisal portion is gradually changed in a natural manner, similar to natural teeth. A color gradient effect of the crown is produced through dipping in or brush-coating with yttrium or ytterbium salt solution. Moreover, the present invention involves simple operating steps and low cost while providing high consistency in quality.