[Objective] This study was to explore the effects of dilute acid hydrolysis on fermentative biohydrogen production capacity of maize stalk. [Method] Using maize stalks subjected to mechanical disintegration,steam expl...[Objective] This study was to explore the effects of dilute acid hydrolysis on fermentative biohydrogen production capacity of maize stalk. [Method] Using maize stalks subjected to mechanical disintegration,steam explosion and dilute acid hydrolysis as experimental materials,we measured and analyzed the effects of different treatments and particle size of maize stalk were analyzed. [Result] The optimal fermentative biohydrogen production was found under following parameters:pretreatment of 0.8% dilute H2SO4 following steam explosion,particle size of maize stalk of 0.425-0.850 mm,liquid-solid ratio [0.8% H2SO4 (M):stalk (W)] of 10:1. [Conclusion] Post steam explosion,dilute 0.8% dilute H2SO4 intensified hydrolysis on maize stalk could produce fermentative biohydrogen production capacity.展开更多
This work is concentrated on elucidating the mechanism of the electric field enhanced water dissociation. A simple model was established for the theoretical current-voltage characteristics in water dissociation proces...This work is concentrated on elucidating the mechanism of the electric field enhanced water dissociation. A simple model was established for the theoretical current-voltage characteristics in water dissociation process on a bipolar membrane based on the existence of a depletion layer and Onsager's theory. Particular attention was given to the influence of applied voltage on depletion thickness and the dissociation constant. The factors on the water splitting process, such as water diffusivity, water content, ion exchange capacity, temperature, relative permittivity, etc. Were adequately analysed based on the derived model equations and several suggestions were proposed for decreasing the applied voltage in practical operation. The water dissociation tests were conducted and compared with both the theoretical calculation and the measured current-voltage curves reported in the literature, which showed a very good prediction to practical current-voltage behavior of a bipolar membrane at high current densities when the splitting of water actually commenced.展开更多
Underwater imaging posts a challenge due to the degradation by the absorption and scattering occurred during light propagation as well as poor lighting conditions in water medium Although image filtering techniques ar...Underwater imaging posts a challenge due to the degradation by the absorption and scattering occurred during light propagation as well as poor lighting conditions in water medium Although image filtering techniques are utilized to improve image quality effectively, problems of the distortion of image details and the bias of color correction still exist in output images due to the complexity of image texture distribution. This paper proposes a new underwater image enhancement method based on image struc- tural decomposition. By introducing a curvature factor into the Mumford_Shah_G decomposition algorithm, image details and struc- ture components are better preserved without the gradient effect. Thus, histogram equalization and Retinex algorithms are applied in the decomposed structure component for global image enhancement and non-uniform brightness correction for gray level and the color images, then the optical absorption spectrum in water medium is incorporate to improve the color correction. Finally, the en- hauced structure and preserved detail component are re.composed to generate the output. Experiments with real underwater images verify the image improvement by the proposed method in image contrast, brightness and color fidelity.展开更多
Photoelectrodes with a specific structure and composition have been proposed for improving the efficiency of solar water splitting. Here, a novel multijunction structure was fabricated, with Si nanowires as cores, ZnI...Photoelectrodes with a specific structure and composition have been proposed for improving the efficiency of solar water splitting. Here, a novel multijunction structure was fabricated, with Si nanowires as cores, ZnIn2S4 nanosheets as branches, and TiO2 films as sandwiched layers. This junction exhibited a superior photoelectrochemical performance with a maximum photoconversion efficiency of 0.51%, which is 795 and 64 times higher than that of a bare Si wafer and nanowires, respectively. The large enhancement was attributed to the effective electron-hole separation and fast excited carrier transport within the multijunctions resulting from their favorable energy band alignments with water redox potentials, and to the enlarged contact area for facilitating the electron transfer at the multijunction/electrolyte interface.展开更多
基金Supported by National Basic Research Program of China(2006CB708407 2009CB220005)+2 种基金National Natural Science Foun-dation of China (90610001 20871106)Program of 211 Projectfor Zhengzhou University from Ministry of Education~~
文摘[Objective] This study was to explore the effects of dilute acid hydrolysis on fermentative biohydrogen production capacity of maize stalk. [Method] Using maize stalks subjected to mechanical disintegration,steam explosion and dilute acid hydrolysis as experimental materials,we measured and analyzed the effects of different treatments and particle size of maize stalk were analyzed. [Result] The optimal fermentative biohydrogen production was found under following parameters:pretreatment of 0.8% dilute H2SO4 following steam explosion,particle size of maize stalk of 0.425-0.850 mm,liquid-solid ratio [0.8% H2SO4 (M):stalk (W)] of 10:1. [Conclusion] Post steam explosion,dilute 0.8% dilute H2SO4 intensified hydrolysis on maize stalk could produce fermentative biohydrogen production capacity.
基金Supported by the National Natural Science Foundation of China (No. 29976040), the Natural Science Foundation of Anhui Province (No. 99045431) and Youth Foundation of USTC.
文摘This work is concentrated on elucidating the mechanism of the electric field enhanced water dissociation. A simple model was established for the theoretical current-voltage characteristics in water dissociation process on a bipolar membrane based on the existence of a depletion layer and Onsager's theory. Particular attention was given to the influence of applied voltage on depletion thickness and the dissociation constant. The factors on the water splitting process, such as water diffusivity, water content, ion exchange capacity, temperature, relative permittivity, etc. Were adequately analysed based on the derived model equations and several suggestions were proposed for decreasing the applied voltage in practical operation. The water dissociation tests were conducted and compared with both the theoretical calculation and the measured current-voltage curves reported in the literature, which showed a very good prediction to practical current-voltage behavior of a bipolar membrane at high current densities when the splitting of water actually commenced.
基金supported by the National Natural Science Foundation of China (Grant Nos.60772058 and 61271406)
文摘Underwater imaging posts a challenge due to the degradation by the absorption and scattering occurred during light propagation as well as poor lighting conditions in water medium Although image filtering techniques are utilized to improve image quality effectively, problems of the distortion of image details and the bias of color correction still exist in output images due to the complexity of image texture distribution. This paper proposes a new underwater image enhancement method based on image struc- tural decomposition. By introducing a curvature factor into the Mumford_Shah_G decomposition algorithm, image details and struc- ture components are better preserved without the gradient effect. Thus, histogram equalization and Retinex algorithms are applied in the decomposed structure component for global image enhancement and non-uniform brightness correction for gray level and the color images, then the optical absorption spectrum in water medium is incorporate to improve the color correction. Finally, the en- hauced structure and preserved detail component are re.composed to generate the output. Experiments with real underwater images verify the image improvement by the proposed method in image contrast, brightness and color fidelity.
基金Acknowledgements This work was supported by the National Natural Science Foundation of China (Nos. 51422206 and 51372159), 1000 Talents Plan for Young Researchers, "Shuangchuang" Program of Jiangsu Province, a Project Supported by Jiangsu Science and Technology Committee for Distinguished Young Scholars (No. BK20140009), the National Basic Research Program of China (973 Program) (No. 2015CB358600) and a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD). We also acknowledge Jiangsu Nata Opto- electronic Materials Co. Ltd. for providing high purity TDMAT precursor for deposition of TiO2 thin films.
文摘Photoelectrodes with a specific structure and composition have been proposed for improving the efficiency of solar water splitting. Here, a novel multijunction structure was fabricated, with Si nanowires as cores, ZnIn2S4 nanosheets as branches, and TiO2 films as sandwiched layers. This junction exhibited a superior photoelectrochemical performance with a maximum photoconversion efficiency of 0.51%, which is 795 and 64 times higher than that of a bare Si wafer and nanowires, respectively. The large enhancement was attributed to the effective electron-hole separation and fast excited carrier transport within the multijunctions resulting from their favorable energy band alignments with water redox potentials, and to the enlarged contact area for facilitating the electron transfer at the multijunction/electrolyte interface.