[Objective] This study was to screen out endophytic fungal strains from the bark of Juglans regia L. [Method] The bark of J. regia was washed with running water and placed on medium to let the fungi grown; the fungal ...[Objective] This study was to screen out endophytic fungal strains from the bark of Juglans regia L. [Method] The bark of J. regia was washed with running water and placed on medium to let the fungi grown; the fungal colonies were studied via morphological observation and anti-microbial activity. [Result] An endophytic fungus showing broad-scope, highly active anti-microbial activity was screened out. This fungus showed anti-microbial activity seven Gram-positive and four Gram-negative bacterial indicators, six skin pathogenic fungi and seven pathogenic fungi to different extent. Morphological observation on the ITS sequence showed that this fungus is consistent with Paecilomyces lilacinus in genus Paecilomyces bainier（with homology of over 99%）. Accordingly this fungus was designated as Paecilomyces lilacinus JY-1024. [Conclusion] This study for the first time reported the isolation of P. lilacinus from J. regia and its in vitro antimicrobial activity to several pathogens.展开更多
On 13 August 2010, a catastrophic debris flow with a volume of 1.17 million m3 occurred in Xiaojiagou Ravine near Yingxiu town of Wenchuan county in Sichuan Province, China. The main source material was the landslide ...On 13 August 2010, a catastrophic debris flow with a volume of 1.17 million m3 occurred in Xiaojiagou Ravine near Yingxiu town of Wenchuan county in Sichuan Province, China. The main source material was the landslide deposits retained in the ravine during the 2008 Wenchuan earthquake. This paper describes a two-dimensional hybrid numerical method that simulates the entire process of the debris flow from initiation to transportation and finally to deposition. The study area is discretized into a grid of square zones. A two dimensional finite difference method is then applied to simulate the rainfall-runoff and debris flow runout processes. The analysis is divided into three steps; namely, rainfall-runoff simulation, mixing water and solid materials, and debris flow runout simulation. The rainfall-runoff simulation is firstly conducted to obtain the cumulative runoff near the location of main source material and at the outlet of the first branch. The water and solid materials are then mixed to create an inflow hydrograph for the debris flow runout simulation. The occurrence time and volume of the debris flow can be estimated in this step. Finally the runout process of the debris flow is simulated. When the yield stress is high, it controls the deposition zone. When the yield stress is medium or low, both yield stress and viscosity influence the deposition zone. The flow velocity is largely influenced by the viscosity. The estimated yield stress by the equation, ty = pghsinO, and the estimated viscosity by the equation established by Bisantino et al. （2010） provide good estimates of the area of the debris flow fan and the distribution of deposition depth.展开更多
A new control strategy named adjacent coupling error strategy is proposed to multi-motor drive system. The adjacent coupling error control scheme is developed considering the tracking speed error in one motor and the ...A new control strategy named adjacent coupling error strategy is proposed to multi-motor drive system. The adjacent coupling error control scheme is developed considering the tracking speed error in one motor and the synchronous error among adjacent motors simultaneously. In the strategy, due to non-linear effects of the two mentioned errors to the motion control of motor i, an adaptive fuzzy logic controller is designed to decide the control variable of the motor drive system. The multi-motor drive system is modeled and simulated by SIMULINK. The simulated researches show that the proposed strategy improves the synchronization, stabilization, and convergence of the multi-motor system.展开更多
Modelling and simulation has become an important tool in research and development. Simulation models are used to develop better understanding of the internal properties and impact of various parameters on the final qu...Modelling and simulation has become an important tool in research and development. Simulation models are used to develop better understanding of the internal properties and impact of various parameters on the final quality of the product or process. Simulation model reduces the number of experiments and saves the wastage of material, time and money and are widely used in automobile industry, aircrafts manufacturing, process engineering, training for military, health care sector and many more. Wood Plastic Composite （WPC） is a bio-composite made by mixing wood fibers and plastic granules together at high temperature by compression molding or injection molding. A large quantity of WPC is rejected due to poor quality and low mechanical strength. There is a need to improve the understanding of the wood plastic composites, with both theoretical and experimental analysis. The impact of various parameters and processing conditions on the final product is not known to the industry people, due to less simulation models in this field. A new simulation software WPC Soft is developed to predict the mechanical and thermal properties of WPC. The software can predict the mechanical and thermal properties of WPC. The simulation results were validated with the experimental results and it was observed that the predicted values are quite close to the experimental values and with the further refining of the model, prediction can be further improved. The present simulation software can be easily used by the industry people and it requires very little knowledge of computers or modeling for its operation.展开更多
5-Azacytidine, a DNA methyltransferase inhibitor, led to significant changes in the secondary metabolism of the plant endophytic fungus, Pestalotiopsis microspora. Analysis of the culture broth extract led to the isol...5-Azacytidine, a DNA methyltransferase inhibitor, led to significant changes in the secondary metabolism of the plant endophytic fungus, Pestalotiopsis microspora. Analysis of the culture broth extract led to the isolation of a new compound, 4＇-forrnamidophenyl-5-methoxybenzoate （1）, along with seven known polyketides, 4-hydroxybenzoic acid （2）, LL-P880ct （3）, 1＇-hydroxy-4-methoxy-6-pentyl-2H-pyran-2-one （4）, pestalotiollide B （5）, pestalotiopyrone G （6）, endocrocin （7） and 2＇-hydroxy- 6＇-hydroxymethyl-4＇-methylphenyl-2,6-dihydroxy-3-（2-isopentenyl）benzoate （8）. HPLC profiles revealed that all compounds except for 4 belonged to the newly induced secondary metabolites. In addition, all compounds were proved to be devoid of significant antifungal activity in the bioassays.展开更多
Preliminary design and simulation of a free piston engine suitable for small-scale energy production in distributed energy systems is presented in this paper.The properties,particularly the properties of gas seals of ...Preliminary design and simulation of a free piston engine suitable for small-scale energy production in distributed energy systems is presented in this paper.The properties,particularly the properties of gas seals of the engine are simulated using a simulation program developed for this case,and the results are utilized in preliminary main design parameter selection.The engine simulation program was developed by combining and modifying the source codes of the simulation and calculation programs obtained from Helsinki University of Technology,Tampere University of Technology,and Lappeenranta University of Technology.Because of the contact-free labyrinth seal used in the piston,the efficiency of the motor is lower than the efficiency of a conventional motor with oil lubricated piston rings.On the other hand,the lack of bearing losses,and the lack of losses associated with a crankshaft system and a gearbox,as well as the lack of lubrication oil expenses,compensates this effect.As a net result,this new motor would perform slightly better than the conventional one.Being completely oil-free,it is very environmentally friendly,and its exhaust gases are completely free of oil residuals which are causing problems in normal gas motors.展开更多
In this paper, a one-dimensional bipolar Euler-Poisson system （a hydrodynamic model） from semiconductors or plasmas with boundary effects is considered. This system takes the form of Euler-Poisson with an electric f...In this paper, a one-dimensional bipolar Euler-Poisson system （a hydrodynamic model） from semiconductors or plasmas with boundary effects is considered. This system takes the form of Euler-Poisson with an electric field and frictional damping added to the momentum equations. The large-time behavior of uniformly bounded weak solutions to the initial-boundary value problem for the one-dimensional bipolar Euler-Poisson system is firstly presented. Next, two particle densities and the corresponding current momenta are verified to satisfy the porous medium equation and the classical Darcy＇s law time asymp- totically. Finally, as a by-product, the quasineutral limit of the weak solutions to the initial-boundary value problem is investigated in the sense that the bounded L∞ entropy solution to the one-dimensional bipolar Euler-Poisson system converges to that of the cor- responding one-dimensional compressible Euler equations with damping exponentially fast as t → ＋∞. As far as we know, this is the first result about the asymptotic behavior and the quasineutral limit for the one-dimensional bipolar Euler-Poisson system with boundary effects and a vacuum.展开更多
基金Supported by Science Research Fund from Yunnan Provincial Education Department(09Y0503)~~
文摘[Objective] This study was to screen out endophytic fungal strains from the bark of Juglans regia L. [Method] The bark of J. regia was washed with running water and placed on medium to let the fungi grown; the fungal colonies were studied via morphological observation and anti-microbial activity. [Result] An endophytic fungus showing broad-scope, highly active anti-microbial activity was screened out. This fungus showed anti-microbial activity seven Gram-positive and four Gram-negative bacterial indicators, six skin pathogenic fungi and seven pathogenic fungi to different extent. Morphological observation on the ITS sequence showed that this fungus is consistent with Paecilomyces lilacinus in genus Paecilomyces bainier（with homology of over 99%）. Accordingly this fungus was designated as Paecilomyces lilacinus JY-1024. [Conclusion] This study for the first time reported the isolation of P. lilacinus from J. regia and its in vitro antimicrobial activity to several pathogens.
基金support from Sichuan Provincial Department of Transportation and Communications,the National Basic Research Program of China (Grant No.2011CB013506)the Research Grants Council of the Hong Kong SAR (Grant No.622210)
文摘On 13 August 2010, a catastrophic debris flow with a volume of 1.17 million m3 occurred in Xiaojiagou Ravine near Yingxiu town of Wenchuan county in Sichuan Province, China. The main source material was the landslide deposits retained in the ravine during the 2008 Wenchuan earthquake. This paper describes a two-dimensional hybrid numerical method that simulates the entire process of the debris flow from initiation to transportation and finally to deposition. The study area is discretized into a grid of square zones. A two dimensional finite difference method is then applied to simulate the rainfall-runoff and debris flow runout processes. The analysis is divided into three steps; namely, rainfall-runoff simulation, mixing water and solid materials, and debris flow runout simulation. The rainfall-runoff simulation is firstly conducted to obtain the cumulative runoff near the location of main source material and at the outlet of the first branch. The water and solid materials are then mixed to create an inflow hydrograph for the debris flow runout simulation. The occurrence time and volume of the debris flow can be estimated in this step. Finally the runout process of the debris flow is simulated. When the yield stress is high, it controls the deposition zone. When the yield stress is medium or low, both yield stress and viscosity influence the deposition zone. The flow velocity is largely influenced by the viscosity. The estimated yield stress by the equation, ty = pghsinO, and the estimated viscosity by the equation established by Bisantino et al. （2010） provide good estimates of the area of the debris flow fan and the distribution of deposition depth.
基金National Natural Science Foundation of China (No.60774023)
文摘A new control strategy named adjacent coupling error strategy is proposed to multi-motor drive system. The adjacent coupling error control scheme is developed considering the tracking speed error in one motor and the synchronous error among adjacent motors simultaneously. In the strategy, due to non-linear effects of the two mentioned errors to the motion control of motor i, an adaptive fuzzy logic controller is designed to decide the control variable of the motor drive system. The multi-motor drive system is modeled and simulated by SIMULINK. The simulated researches show that the proposed strategy improves the synchronization, stabilization, and convergence of the multi-motor system.
文摘Modelling and simulation has become an important tool in research and development. Simulation models are used to develop better understanding of the internal properties and impact of various parameters on the final quality of the product or process. Simulation model reduces the number of experiments and saves the wastage of material, time and money and are widely used in automobile industry, aircrafts manufacturing, process engineering, training for military, health care sector and many more. Wood Plastic Composite （WPC） is a bio-composite made by mixing wood fibers and plastic granules together at high temperature by compression molding or injection molding. A large quantity of WPC is rejected due to poor quality and low mechanical strength. There is a need to improve the understanding of the wood plastic composites, with both theoretical and experimental analysis. The impact of various parameters and processing conditions on the final product is not known to the industry people, due to less simulation models in this field. A new simulation software WPC Soft is developed to predict the mechanical and thermal properties of WPC. The software can predict the mechanical and thermal properties of WPC. The simulation results were validated with the experimental results and it was observed that the predicted values are quite close to the experimental values and with the further refining of the model, prediction can be further improved. The present simulation software can be easily used by the industry people and it requires very little knowledge of computers or modeling for its operation.
基金National Natural Science Foundation(Grant No.31660251)Fundamental Research Funds for the Central Universities(Grant No.0903005203401)the Start-up Fund for the“Hundred Young-Talent Scheme”Professorship(Grant No.0236011104424)
文摘5-Azacytidine, a DNA methyltransferase inhibitor, led to significant changes in the secondary metabolism of the plant endophytic fungus, Pestalotiopsis microspora. Analysis of the culture broth extract led to the isolation of a new compound, 4＇-forrnamidophenyl-5-methoxybenzoate （1）, along with seven known polyketides, 4-hydroxybenzoic acid （2）, LL-P880ct （3）, 1＇-hydroxy-4-methoxy-6-pentyl-2H-pyran-2-one （4）, pestalotiollide B （5）, pestalotiopyrone G （6）, endocrocin （7） and 2＇-hydroxy- 6＇-hydroxymethyl-4＇-methylphenyl-2,6-dihydroxy-3-（2-isopentenyl）benzoate （8）. HPLC profiles revealed that all compounds except for 4 belonged to the newly induced secondary metabolites. In addition, all compounds were proved to be devoid of significant antifungal activity in the bioassays.
基金Project is financed by the Technology Development Center of Finland (Tekes)
文摘Preliminary design and simulation of a free piston engine suitable for small-scale energy production in distributed energy systems is presented in this paper.The properties,particularly the properties of gas seals of the engine are simulated using a simulation program developed for this case,and the results are utilized in preliminary main design parameter selection.The engine simulation program was developed by combining and modifying the source codes of the simulation and calculation programs obtained from Helsinki University of Technology,Tampere University of Technology,and Lappeenranta University of Technology.Because of the contact-free labyrinth seal used in the piston,the efficiency of the motor is lower than the efficiency of a conventional motor with oil lubricated piston rings.On the other hand,the lack of bearing losses,and the lack of losses associated with a crankshaft system and a gearbox,as well as the lack of lubrication oil expenses,compensates this effect.As a net result,this new motor would perform slightly better than the conventional one.Being completely oil-free,it is very environmentally friendly,and its exhaust gases are completely free of oil residuals which are causing problems in normal gas motors.
基金supported by the National Natural Science Foundation of China(No.11171223)the Innovation Program of Shanghai Municipal Education Commission(No.13ZZ109)
文摘In this paper, a one-dimensional bipolar Euler-Poisson system （a hydrodynamic model） from semiconductors or plasmas with boundary effects is considered. This system takes the form of Euler-Poisson with an electric field and frictional damping added to the momentum equations. The large-time behavior of uniformly bounded weak solutions to the initial-boundary value problem for the one-dimensional bipolar Euler-Poisson system is firstly presented. Next, two particle densities and the corresponding current momenta are verified to satisfy the porous medium equation and the classical Darcy＇s law time asymp- totically. Finally, as a by-product, the quasineutral limit of the weak solutions to the initial-boundary value problem is investigated in the sense that the bounded L∞ entropy solution to the one-dimensional bipolar Euler-Poisson system converges to that of the cor- responding one-dimensional compressible Euler equations with damping exponentially fast as t → ＋∞. As far as we know, this is the first result about the asymptotic behavior and the quasineutral limit for the one-dimensional bipolar Euler-Poisson system with boundary effects and a vacuum.
