Dissymmetry model of molecular polarizability divided into some layers within a sphere,some rules and sequence according to the magnitude of polarizability replaced by bond refraction for many groups have been suggest...Dissymmetry model of molecular polarizability divided into some layers within a sphere,some rules and sequence according to the magnitude of polarizability replaced by bond refraction for many groups have been suggested.The relationship between the dissymmetry of molecular polarizability arrounding the dissymmetric carbon atom and the direction of optical activity has been discussed .The accuracy is above 95 persent to use our model and rules to determine over 6000 compounds of optical activity.展开更多
In the present study,a combined bonded multi-sphere model was developed,validated,and applied to simulate the motion and breakage behavior of wet fibers in a fluidized bed.The effects of particle resolution,bond numbe...In the present study,a combined bonded multi-sphere model was developed,validated,and applied to simulate the motion and breakage behavior of wet fibers in a fluidized bed.The effects of particle resolution,bond number,and humidity coefficient(γ)on fiber breakage rate,breakage location,and fragment size distribution were systematically investigated.Results show that increasing particle resolution from 3 to 6 generally reduces fiber breakage.While a higher bond number lowers the probability of breakage.Two different breakage modes are identified under varyingγvalues:Mode 1,characterized by breakage due to collisions between rapidly falling individual fibers and fiber clusters,and Mode 2,arising from impacts between fiber clusters and the bed bottom.Asγincreases within a certain range,the dominant breakage mechanism transitions from Mode 1 to a mixed mode involving both Modes 1 and 2,accompanied by a shift in the primary breakage location from the corner region toward the center region of the bed.All these findings provide valuable insights into the dynamics of wet fiber fluidization and offer guidance for optimizing wet fiber breakage behavior in real applications.展开更多
The anion coordination complex,[ClPt(bpt)4]Cl (bpt=N,N'-bis(3-pyridylmethyl)-2-thiourea),was synthesized and studied by X-ray crystal structure analysis,NMR and FAB mass spectra. In the solid state,the Pt(bpt)4 an...The anion coordination complex,[ClPt(bpt)4]Cl (bpt=N,N'-bis(3-pyridylmethyl)-2-thiourea),was synthesized and studied by X-ray crystal structure analysis,NMR and FAB mass spectra. In the solid state,the Pt(bpt)4 anion receptor adopts a cone conformation to bind the chloride anion through hydrogen bonds and electrostatic interaction in which the four branches of the thiourea ligands bind the chloride anion to form N-H…Cl-hydrogen bonds (3.49-3.81). The entraped chloride anion is situated above the Pt(Ⅱ) center at 3.52 . Further second-sphere coordination assemby from the Pt(bpt)4 core with 8 zinc(Ⅱ) tetraphenylporphyrins (ZnPr) is discussed.展开更多
文摘Dissymmetry model of molecular polarizability divided into some layers within a sphere,some rules and sequence according to the magnitude of polarizability replaced by bond refraction for many groups have been suggested.The relationship between the dissymmetry of molecular polarizability arrounding the dissymmetric carbon atom and the direction of optical activity has been discussed .The accuracy is above 95 persent to use our model and rules to determine over 6000 compounds of optical activity.
文摘In the present study,a combined bonded multi-sphere model was developed,validated,and applied to simulate the motion and breakage behavior of wet fibers in a fluidized bed.The effects of particle resolution,bond number,and humidity coefficient(γ)on fiber breakage rate,breakage location,and fragment size distribution were systematically investigated.Results show that increasing particle resolution from 3 to 6 generally reduces fiber breakage.While a higher bond number lowers the probability of breakage.Two different breakage modes are identified under varyingγvalues:Mode 1,characterized by breakage due to collisions between rapidly falling individual fibers and fiber clusters,and Mode 2,arising from impacts between fiber clusters and the bed bottom.Asγincreases within a certain range,the dominant breakage mechanism transitions from Mode 1 to a mixed mode involving both Modes 1 and 2,accompanied by a shift in the primary breakage location from the corner region toward the center region of the bed.All these findings provide valuable insights into the dynamics of wet fiber fluidization and offer guidance for optimizing wet fiber breakage behavior in real applications.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 50673098 & 20772152)Renmin University of China, State Key Laboratory of Structure Chemistry (Grant No. 20080052)
文摘The anion coordination complex,[ClPt(bpt)4]Cl (bpt=N,N'-bis(3-pyridylmethyl)-2-thiourea),was synthesized and studied by X-ray crystal structure analysis,NMR and FAB mass spectra. In the solid state,the Pt(bpt)4 anion receptor adopts a cone conformation to bind the chloride anion through hydrogen bonds and electrostatic interaction in which the four branches of the thiourea ligands bind the chloride anion to form N-H…Cl-hydrogen bonds (3.49-3.81). The entraped chloride anion is situated above the Pt(Ⅱ) center at 3.52 . Further second-sphere coordination assemby from the Pt(bpt)4 core with 8 zinc(Ⅱ) tetraphenylporphyrins (ZnPr) is discussed.