Bioconversion of lignocellulosic wastes to higher value products through fungal fermentation has economic and ecological benefits. In this study, to develop an effective strategy for production of manganese peroxidase...Bioconversion of lignocellulosic wastes to higher value products through fungal fermentation has economic and ecological benefits. In this study, to develop an effective strategy for production of manganese peroxidase(Mn P)from cassava residue by Phanerochaete chrysosporium in solid state fermentation, the stimulators of Mn P production were screened and their concentrations were optimized by one-at-a-time experiment and Box–Behnken design. The maximum Mn P activity of 186.38 nkat·g-1dry mass of the sample was achieved after 6 days of fermentation with the supplement of 79.5 mmol·L-1·kg-1acetic acid, 3.21 ml·kg-1soybean oil, and 28.5 g·kg-1alkaline lignin, indicating that cassava residue is a promising substrate for Mn P production in solid state fermentation. Meanwhile, in vitro decolorization of indigo carmine by the crude Mn P was also carried out, attaining the ratio of 90.18% after 6 h of incubation. An oxidative mechanism of indigo carmine decolorization by Mn P was proposed based on the analysis of intermediate metabolites with ultra-high performance liquid chromatography and gas chromatography tandem mass spectrometry. Using the crude Mn P produced from cassava residue for indigo carmine decolorization gives an effective approach to treat dyeing effluents.展开更多
Many applications in computational science and engineering require the computation of eigenvalues and vectors of dense symmetric or Hermitian matrices. For example, in DFT （density functional theory） calculations on...Many applications in computational science and engineering require the computation of eigenvalues and vectors of dense symmetric or Hermitian matrices. For example, in DFT （density functional theory） calculations on modern supercomputers 10% to 30% of the eigenvalues and eigenvectors of huge dense matrices have to be calculated. Therefore, performance and parallel scaling of the used eigensolvers is of upmost interest. In this article different routines of the linear algebra packages ScaLAPACK and Elemental for parallel solution of the symmetric eigenvalue problem are compared concerning their performance on the BlueGene/P supercomputer. Parameters for performance optimization are adjusted for the different data distribution methods used in the two libraries. It is found that for all test cases the new library Elemental which uses a two-dimensional element by element distribution of the matrices to the processors shows better performance than the old ScaLAPACK library which uses a block-cyclic distribution.展开更多
In this work,GaN-based light-emitting diodes(LEDs) with a p-GaN/i-InGaN short-period superlattice(SPSL) structure,p-GaN and undoped GaN last quantum barrier(LQB) have been numerically investigated by using the APSYS s...In this work,GaN-based light-emitting diodes(LEDs) with a p-GaN/i-InGaN short-period superlattice(SPSL) structure,p-GaN and undoped GaN last quantum barrier(LQB) have been numerically investigated by using the APSYS simulation software.It has been found that the efficiency droop is significantly improved when the undoped GaN LQB in a typical blue LED is replaced by a p-GaN/i-InGaN SPSL structure.According to the simulation analysis,using the p-GaN/i-InGaN SPSL structure as LQB is beneficial to increasing the hole injection efficiency and decreasing the electron current leakage.Therefore,the radiative recombination and optical power are enhanced.展开更多
基金Supported by the Science&Technology Program of Jiangsu Province(BE2011623)the Scientific Research Project of Provincial Environmental Protection Bureau of Jiangsu Province(2012047)
文摘Bioconversion of lignocellulosic wastes to higher value products through fungal fermentation has economic and ecological benefits. In this study, to develop an effective strategy for production of manganese peroxidase(Mn P)from cassava residue by Phanerochaete chrysosporium in solid state fermentation, the stimulators of Mn P production were screened and their concentrations were optimized by one-at-a-time experiment and Box–Behnken design. The maximum Mn P activity of 186.38 nkat·g-1dry mass of the sample was achieved after 6 days of fermentation with the supplement of 79.5 mmol·L-1·kg-1acetic acid, 3.21 ml·kg-1soybean oil, and 28.5 g·kg-1alkaline lignin, indicating that cassava residue is a promising substrate for Mn P production in solid state fermentation. Meanwhile, in vitro decolorization of indigo carmine by the crude Mn P was also carried out, attaining the ratio of 90.18% after 6 h of incubation. An oxidative mechanism of indigo carmine decolorization by Mn P was proposed based on the analysis of intermediate metabolites with ultra-high performance liquid chromatography and gas chromatography tandem mass spectrometry. Using the crude Mn P produced from cassava residue for indigo carmine decolorization gives an effective approach to treat dyeing effluents.
文摘Many applications in computational science and engineering require the computation of eigenvalues and vectors of dense symmetric or Hermitian matrices. For example, in DFT （density functional theory） calculations on modern supercomputers 10% to 30% of the eigenvalues and eigenvectors of huge dense matrices have to be calculated. Therefore, performance and parallel scaling of the used eigensolvers is of upmost interest. In this article different routines of the linear algebra packages ScaLAPACK and Elemental for parallel solution of the symmetric eigenvalue problem are compared concerning their performance on the BlueGene/P supercomputer. Parameters for performance optimization are adjusted for the different data distribution methods used in the two libraries. It is found that for all test cases the new library Elemental which uses a two-dimensional element by element distribution of the matrices to the processors shows better performance than the old ScaLAPACK library which uses a block-cyclic distribution.
基金supported by the National Natural Science Foundation of China (Grant No. 61176043)the Doctoral Fund of Ministry of Educationof China (Grant No. 20060574007)+3 种基金the Production and Research Projectof Guangdong Province and Ministry of Education (Grant Nos.2009B090300338,2010B090400192)the LED Industry Project of Special Funds of Strategic Emerging Industries of Guangdong Province in 2011(Grant No. 2010A081002005)the LED Industry Project of Special Fundsof Strategic Emerging Industries of Guangdong Province in 2012 (GrantNo. 2011A081301003)the Science and Technology Program of Guangzhou Huadu District (Grant Nos. HD10CXY-G002,HD10CXY-G013)
文摘In this work,GaN-based light-emitting diodes(LEDs) with a p-GaN/i-InGaN short-period superlattice(SPSL) structure,p-GaN and undoped GaN last quantum barrier(LQB) have been numerically investigated by using the APSYS simulation software.It has been found that the efficiency droop is significantly improved when the undoped GaN LQB in a typical blue LED is replaced by a p-GaN/i-InGaN SPSL structure.According to the simulation analysis,using the p-GaN/i-InGaN SPSL structure as LQB is beneficial to increasing the hole injection efficiency and decreasing the electron current leakage.Therefore,the radiative recombination and optical power are enhanced.
