In order to distinguish eight carnation cultivars, 40 samples were analyzed by Fourier transform infrared (FI'IR) spectroscopy combined with principal component analysis (PCA) and hierarchical cluster analysis (...In order to distinguish eight carnation cultivars, 40 samples were analyzed by Fourier transform infrared (FI'IR) spectroscopy combined with principal component analysis (PCA) and hierarchical cluster analysis (HCA). According to the results, infrared spectra of eight carnation cuhivars were similar, but signifi- cant differences were observed in wave numbers and absorption peak intensities in the range of 1 800 -700cm-1. The second order derivative spectra in the range of 1 800 -700 cm -l were selected to perform principal component analysis (PCA) and hierarchical cluster analysis (HCA). The cumulative contribution rate of the first three principal components reached 96.2%. The classification accuracy rate of PCA and HCA was 95% and 100%, respectively. The results demonstrated that Fourier transform infrared (FTIR) spectroscopy combined with principal component analysis (PCA) and hierarchical cluster analysis (HCA) could be used for identification of different carnation cultivars.展开更多
The potential for mitigating climate change is growing worldwide,with an increasing emphasis on reducing CO_(2)emissions and minimising the impact on the environment.African continent is faced with the unique challeng...The potential for mitigating climate change is growing worldwide,with an increasing emphasis on reducing CO_(2)emissions and minimising the impact on the environment.African continent is faced with the unique challenge of climate change whilst coping with extreme poverty,explosive population growth and economic difficulties.CO_(2)emission patterns in Africa are analysed in this study to understand primary CO_(2)sources and underlying driving forces further.Data are examined using gravity model,logarithmic mean divisia index and Tapio's decoupling indicator of CO_(2)emissions from economic development in 20 selected African countries during 1984-2014.Results reveal that CO_(2)emissions increased by 2.11%(453.73 million ton)over the research period.Gravity centre for African CO_(2)emissions had shifted towards the northeast direction.Population and economic growth were primary driving forces of CO_(2)emissions.Industrial structure and emission efficiency effects partially offset the growth of CO_(2)emissions.The economic growth effect was an offset factor in central African countries and Zimbabwe due to political instability and economic mismanagement.Industrial structure and emission efficiency were insufficient to decouple economic development from CO_(2)emissions and relieve the pressure of population explosion on CO_(2)emissions in Africa.Thus,future efforts in reducing CO_(2)emissions should focus on scaleup energy-efficient technologies,renewable energy update,emission pricing and long-term green development towards sustainable development goals by 2030.展开更多
The purpose of this study was to analyze the influence of the injection pressure and orifice diameter on the spray characteristics of soybean biodiesel.The macroscopic spray characteristics of the spray tip penetratio...The purpose of this study was to analyze the influence of the injection pressure and orifice diameter on the spray characteristics of soybean biodiesel.The macroscopic spray characteristics of the spray tip penetration(STP)and spray cone angle(SCA)were tested with a high-speed camera system.The microscopic spray characteristics,such as the statistical size distribution,Sauter mean diameter(SMD),representative diameters and dispersion boundary,were obtained using a Malvern laser particle size analyzer(PSA).The test results showed that with an increasing injection pressure,the STP and the SCA of the biodiesel increased,but the curves of size-volume distribution and cumulative volume distribution of the atomized droplets shifted to smaller diameters.The SMD and representative diameters decreased,and the dispersion boundary was reduced.Moreover,with a decreasing orifice diameter,longer STP and smaller SCA values were observed.Similarly,the size distribution curves of the atomized biodiesel droplets shifted to smaller diameters.The SMD and representative diameters were reduced,and the relative size range of the atomized biodiesel droplets was enlarged.Higher injection pressures and smaller orifice diameters improved the biodiesel atomization;however,the smaller orifice diameters caused an inhomogeneous size distribution of the atomized biodiesel droplets.展开更多
In this paper, a kind of novel water-soluble chitosan-polydopamine (CHT-PDA) nanoparticles with a hydrody- namic diameter (Dh) around 10 nm were reported by the combination of self-polymerization of PDA and electr...In this paper, a kind of novel water-soluble chitosan-polydopamine (CHT-PDA) nanoparticles with a hydrody- namic diameter (Dh) around 10 nm were reported by the combination of self-polymerization of PDA and electro- static complexation between PDA and CHT in water/DMSO (W/D) mixture at the molar fraction of DMSO (XDMSO =0.37). The preparation method was efficient with a yield of 98% around. The as-prepared water-soluble CHT-PDA nanoparticles exhibited effective UV-screen ability, enhanced visible-light transmittance and good cyto- compatibility via MTT assay, which might be used in transparent formulation for UV protection usage, especially in biological field including sun care application.展开更多
基金Supported by National Natural Science Foundation of China"Vibration Spectrum-based Diagnosis of Biological Diseases in Broad Bean"(30960179)Science and Technology Innovation Program for Universities in Yunnan Province
文摘In order to distinguish eight carnation cultivars, 40 samples were analyzed by Fourier transform infrared (FI'IR) spectroscopy combined with principal component analysis (PCA) and hierarchical cluster analysis (HCA). According to the results, infrared spectra of eight carnation cuhivars were similar, but signifi- cant differences were observed in wave numbers and absorption peak intensities in the range of 1 800 -700cm-1. The second order derivative spectra in the range of 1 800 -700 cm -l were selected to perform principal component analysis (PCA) and hierarchical cluster analysis (HCA). The cumulative contribution rate of the first three principal components reached 96.2%. The classification accuracy rate of PCA and HCA was 95% and 100%, respectively. The results demonstrated that Fourier transform infrared (FTIR) spectroscopy combined with principal component analysis (PCA) and hierarchical cluster analysis (HCA) could be used for identification of different carnation cultivars.
基金supported by the National Water Pollution Control and Treatment Science and Technology Major Project(No.2017ZX07101001)the National Natural Science Foundation of China(Nos.41690142 and 41371535)the Fundamental Research Funds for the Central Universities(No.SWU019047)。
文摘The potential for mitigating climate change is growing worldwide,with an increasing emphasis on reducing CO_(2)emissions and minimising the impact on the environment.African continent is faced with the unique challenge of climate change whilst coping with extreme poverty,explosive population growth and economic difficulties.CO_(2)emission patterns in Africa are analysed in this study to understand primary CO_(2)sources and underlying driving forces further.Data are examined using gravity model,logarithmic mean divisia index and Tapio's decoupling indicator of CO_(2)emissions from economic development in 20 selected African countries during 1984-2014.Results reveal that CO_(2)emissions increased by 2.11%(453.73 million ton)over the research period.Gravity centre for African CO_(2)emissions had shifted towards the northeast direction.Population and economic growth were primary driving forces of CO_(2)emissions.Industrial structure and emission efficiency effects partially offset the growth of CO_(2)emissions.The economic growth effect was an offset factor in central African countries and Zimbabwe due to political instability and economic mismanagement.Industrial structure and emission efficiency were insufficient to decouple economic development from CO_(2)emissions and relieve the pressure of population explosion on CO_(2)emissions in Africa.Thus,future efforts in reducing CO_(2)emissions should focus on scaleup energy-efficient technologies,renewable energy update,emission pricing and long-term green development towards sustainable development goals by 2030.
基金financially supported by the National Natural Science Foundation of China(51806020)the Youth Innovation Team of Shaanxi Universities(Energy Saving and New Energy Vehicles)the Special Funds for Basic Scientific Research of Central Colleges,Chang’an University(310822172203 and 300102228403)。
文摘The purpose of this study was to analyze the influence of the injection pressure and orifice diameter on the spray characteristics of soybean biodiesel.The macroscopic spray characteristics of the spray tip penetration(STP)and spray cone angle(SCA)were tested with a high-speed camera system.The microscopic spray characteristics,such as the statistical size distribution,Sauter mean diameter(SMD),representative diameters and dispersion boundary,were obtained using a Malvern laser particle size analyzer(PSA).The test results showed that with an increasing injection pressure,the STP and the SCA of the biodiesel increased,but the curves of size-volume distribution and cumulative volume distribution of the atomized droplets shifted to smaller diameters.The SMD and representative diameters decreased,and the dispersion boundary was reduced.Moreover,with a decreasing orifice diameter,longer STP and smaller SCA values were observed.Similarly,the size distribution curves of the atomized biodiesel droplets shifted to smaller diameters.The SMD and representative diameters were reduced,and the relative size range of the atomized biodiesel droplets was enlarged.Higher injection pressures and smaller orifice diameters improved the biodiesel atomization;however,the smaller orifice diameters caused an inhomogeneous size distribution of the atomized biodiesel droplets.
基金We thank the National Basic Research Program (No. 2013CB834506), the China National Funds for Distin- guished Young Scholar (No. 21225420), the NationalNatural Science Foundation of China (Nos. 21474062, 21374062, 91527304 and 21404070) and Program of Shanghai Subject Chief Scientist (No. 15XD1502400) for financial support.
文摘In this paper, a kind of novel water-soluble chitosan-polydopamine (CHT-PDA) nanoparticles with a hydrody- namic diameter (Dh) around 10 nm were reported by the combination of self-polymerization of PDA and electro- static complexation between PDA and CHT in water/DMSO (W/D) mixture at the molar fraction of DMSO (XDMSO =0.37). The preparation method was efficient with a yield of 98% around. The as-prepared water-soluble CHT-PDA nanoparticles exhibited effective UV-screen ability, enhanced visible-light transmittance and good cyto- compatibility via MTT assay, which might be used in transparent formulation for UV protection usage, especially in biological field including sun care application.