Showa Denko K.K.(SDK) announced it is building a 5 000 t/a cyclohexanoneplant at Zhejiang Quzhou Juhua Showa Electronic Chemical Materials Co.,Ltd., a joint venture company in which SDK owns a 51% share.The high-purit...Showa Denko K.K.(SDK) announced it is building a 5 000 t/a cyclohexanoneplant at Zhejiang Quzhou Juhua Showa Electronic Chemical Materials Co.,Ltd., a joint venture company in which SDK owns a 51% share.The high-puritycyclohexanone plant will start commercial production in Quzhou,Zhejiang province in August 2010.High-purity cyclohexanone is used as cleaning agent for removal of photo-展开更多
Dust extinction law is crucial to recover the intrinsic energy distribution of celestial objects and infer the characteristics of interstellar dust.Based on the traditional pair method,an improved pair method is propo...Dust extinction law is crucial to recover the intrinsic energy distribution of celestial objects and infer the characteristics of interstellar dust.Based on the traditional pair method,an improved pair method is proposed to model the dust extinguished spectral energy distribution(SED)of an individual star.Instead of the mathematically parameterizing extinction curves,the extinction curves in this work are directly from the silicate-graphite dust model,so that the dust extinction law can be obtained and the dust properties can be analyzed simultaneously.The ATLAS9 stellar model atmosphere is adopted for the intrinsic SEDs in this work,while the silicate-graphite dust model with a dust size distribution of dn da~a^(-a)exp(-a a_(c)),0.005<a<5μmfor each component is adopted for the model extinction curves.One typical extinction tracer in the dense region(V410 Anon9)and one in the diffuse region(Cyg OB2#12)of the Milky Way are chosen to test the reliability and the practicability of the improved pair method in different stellar environments.The results are consistent with their interstellar environments and are in agreement with the previous observations and studies,which prove that the improved pair method is effective and applicable in different stellar environments.In addition to the reliable extinction results,the derived parameters in the dust model can be used to analyze the dust properties,which cannot be achieved by other methods with the mathematical extinction models.With the improved pair method,the stellar parameters can also be inferred and the extinction law beyond the wavelengths of observed data can be predicted based on the dust model as well.展开更多
The acylation of 3-pentanone enamine was studied and a novel formation of 4-pyrones from β-diketone enol esters was found involving an intramolecular O- to C-acyl shift followed by cyclization.
This paper considers another kind of chemical reaction different from [1].Thedifference is that the chemical reactions under consideration are assumed to be heterogeneous,fast,reversible and classical.As a typical exa...This paper considers another kind of chemical reaction different from [1].Thedifference is that the chemical reactions under consideration are assumed to be heterogeneous,fast,reversible and classical.As a typical example,the author reduces this problem to anone phase Stefan problem with noncommon data,and investigates the classical solution aswell as the weak solution.展开更多
文摘Showa Denko K.K.(SDK) announced it is building a 5 000 t/a cyclohexanoneplant at Zhejiang Quzhou Juhua Showa Electronic Chemical Materials Co.,Ltd., a joint venture company in which SDK owns a 51% share.The high-puritycyclohexanone plant will start commercial production in Quzhou,Zhejiang province in August 2010.High-purity cyclohexanone is used as cleaning agent for removal of photo-
基金supported by the National Natural Science Foundation of China(NSFC)through grant Nos.12133002,U2031209 and 12203025Shandong Provincial Natural Science Foundation through project ZR2022QA064the CSST Milky Way and Nearby Galaxies Survey on Dust and Extinction Project CMS-CSST2021-A09。
文摘Dust extinction law is crucial to recover the intrinsic energy distribution of celestial objects and infer the characteristics of interstellar dust.Based on the traditional pair method,an improved pair method is proposed to model the dust extinguished spectral energy distribution(SED)of an individual star.Instead of the mathematically parameterizing extinction curves,the extinction curves in this work are directly from the silicate-graphite dust model,so that the dust extinction law can be obtained and the dust properties can be analyzed simultaneously.The ATLAS9 stellar model atmosphere is adopted for the intrinsic SEDs in this work,while the silicate-graphite dust model with a dust size distribution of dn da~a^(-a)exp(-a a_(c)),0.005<a<5μmfor each component is adopted for the model extinction curves.One typical extinction tracer in the dense region(V410 Anon9)and one in the diffuse region(Cyg OB2#12)of the Milky Way are chosen to test the reliability and the practicability of the improved pair method in different stellar environments.The results are consistent with their interstellar environments and are in agreement with the previous observations and studies,which prove that the improved pair method is effective and applicable in different stellar environments.In addition to the reliable extinction results,the derived parameters in the dust model can be used to analyze the dust properties,which cannot be achieved by other methods with the mathematical extinction models.With the improved pair method,the stellar parameters can also be inferred and the extinction law beyond the wavelengths of observed data can be predicted based on the dust model as well.
文摘The acylation of 3-pentanone enamine was studied and a novel formation of 4-pyrones from β-diketone enol esters was found involving an intramolecular O- to C-acyl shift followed by cyclization.
文摘This paper considers another kind of chemical reaction different from [1].Thedifference is that the chemical reactions under consideration are assumed to be heterogeneous,fast,reversible and classical.As a typical example,the author reduces this problem to anone phase Stefan problem with noncommon data,and investigates the classical solution aswell as the weak solution.
