Cathode activity plays an important role in the improvement of the microbial fuel cells on ocean floor （BMFCs）. A comparison study between Rayon-based （CF-R） and PAN-based carbon fiber （CF-P） cathodes is conduct...Cathode activity plays an important role in the improvement of the microbial fuel cells on ocean floor （BMFCs）. A comparison study between Rayon-based （CF-R） and PAN-based carbon fiber （CF-P） cathodes is conducted in the paper. The two carbon fibers were heat treated to improve cell performance （CF-R-H ＆ CF-P-H）, and were used to build a new BMFCs structure with a foamy carbon anode. The maximum power density was 112.4mWm-2 for CF-R-H, followed by 66.6mWm-2 for CF-R, 49.7 mWm-2 for CF-P-H and 21.6mWm-2 for CF-P respectively. The higher specific area and deep groove make CF-R have a better power output than with CF-P. Meanwhile, heat treatment of carbon fiber can improve cell power, nearly two-fold higher than heat treatment of plain fiber. This improvement may be due to the quinones group formation to accelerate the reduction of oxygen and electron transfer on the fiber surface in the three phase boundary after heat treatment. Compared to PAN-based carbon fiber, Rayon-based carbon fiber would be preferentially selected as cathode in novel BMFCs design due to its high surface area, low cost and higher power. The comparison research is significant for cathode material selection and cell design.展开更多
Microbial fuel cell(MFC) on the ocean floor is a kind of novel energy-harvesting device that can be developed to drive small instruments to work continuously.The shape of electrode has a great effect on the performanc...Microbial fuel cell(MFC) on the ocean floor is a kind of novel energy-harvesting device that can be developed to drive small instruments to work continuously.The shape of electrode has a great effect on the performance of the MFC.In this paper,several shapes of electrode and cell structure were designed,and their performance in MFC were compared in pairs:Mesh(cell-1) vs.flat plate(cell-2),branch(cell-3) vs.cylinder(cell-4),and forest(cell-5) vs.disk(cell-6) FC.Our results showed that the maximum power densities were 16.50,14.20,19.30,15.00,14.64,and 9.95 mWm-2 for cell-1,2,3,4,5 and 6 respectively.And the corre-sponding diffusion-limited currents were 7.16,2.80,18.86,10.50,18.00,and 6.900 mA.The mesh and branch anodes showed higher power densities and much higher diffusion-limited currents than the flat plate and the cylinder anodes respectively due to the low diffusion hindrance with the former anodes.The forest cathode improved by 47% of the power density and by 161% of diffusion-limited current than the disk cathode due to the former's extended solid/liquid/gas three-phase boundary.These results indicated that the shape of electrode is a major parameter that determining the diffusion-limited current of an MFC,and the differences in the elec-trode shape lead to the differences in cell performance.These results would be useful for MFC structure design in practical applica-tions.展开更多
Extensive oedometer tests and physical tests have been conducted on remolded and reconstituted marine soils with different initial water contents and liquid limits. The oedometer test data can be well fitted with a st...Extensive oedometer tests and physical tests have been conducted on remolded and reconstituted marine soils with different initial water contents and liquid limits. The oedometer test data can be well fitted with a straight line in the bilogarithmic ln(1+ e ) ～ lg p plot. The initial effective stress corresponding to the initial void ratio is determined by extrapolation of the bilogarithmic compression line. This new way of extrapolating oedometer test data to the initial void ratio overcomes the difficulty of measuring the residual effective stress of soils in the remolded state. The initial stable compression line of ocean floor deposits under different deposition environments corresponds to the compression line at the sensitivity equal to one. This initial stable compression line obtained in this study is consistent with the available compression line at the sensitivity equal to one which is proposed based on the experimental data of remolded undrained strength and the theoretical concept of Cam clay critical state line.展开更多
A unique sulfonated polyaniline/vanadate composite was synthesized and utilized as a composite anode in microbial fuel cells on ocean floor (BMFCs). X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were em...A unique sulfonated polyaniline/vanadate composite was synthesized and utilized as a composite anode in microbial fuel cells on ocean floor (BMFCs). X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were employed to characterize its chemical composition and morphology. Wettability of the composite anodes decreases due to the addition of polytetrafluoroethylene (PTFE). The electrochemical behavior of the composite anodes was investigated by means of linear sweep voltammetry and Tafel plot measurements. Compared with the plain graphite anode,the composite anode significantly improves the power density,5.5-fold higher,reaching 187.1 mW/m2 and gives a 27-fold higher exchange current density and a higher kinetic activity. A novel synergistic mechanism between sulfonated polyaniline and vanadate is proposed to explain the excellent electrochemical performance. This composite thus has great potential to be used as an anode material for a high-power BMFC.展开更多
人们曾经一度担心:当深埋在地下的最后一滴石油用尽之后,人类将 如何发展.甚至如何生存。读了本文,也许你会觉得“杞人忧天”并非古人的故事。新一代的能源已经显露在地平线上。它正lie frozen in combustible(易燃的)ice crystals(晶体...人们曾经一度担心:当深埋在地下的最后一滴石油用尽之后,人类将 如何发展.甚至如何生存。读了本文,也许你会觉得“杞人忧天”并非古人的故事。新一代的能源已经显露在地平线上。它正lie frozen in combustible(易燃的)ice crystals(晶体)below the ocean floor. 它的名称尚未确定:gas or methane(甲烷)hydrates(水合物;氢氧化物)。 人们如此推测它的由来:organic(有机体的)sediments(沉淀物)have beentrapped for many millions of years by pressure and cold. 这种新能源估计投入商业开采的年限是:15 years may be a reasonable goal“for commercial extraction”. 目前,世界油价连连飞涨,世界经济也深受影响,在此大背景下,这则消息就越发显得令人兴奋不已: While research is at an early stage—just compiling a round inventory(总量)of hydrate formations around the world will take decades—excitement is buildingand some scientists,including officials at the U.S.Energy Department,believelarge—scale commercial exploitation could begin by 2015.化理想为现实,变荒野为坦途,困难和问题一定会接踵而来,但是,在人类的历史上,希望实现总是不可阻挡的。展开更多
SHANDONG Province harbors one of the ten maior families of dishes in China—the Lu-stvle of foed Located next to the Bohai Sea. Shandong Province is filled with many tasty sea treats. There are two branches of Lu-styl...SHANDONG Province harbors one of the ten maior families of dishes in China—the Lu-stvle of foed Located next to the Bohai Sea. Shandong Province is filled with many tasty sea treats. There are two branches of Lu-style food, The dishes popnlar in inner Shandong contain mostly poultry. meat and internat organs of animals. The other branch of Lu-style food, popular in the coastal area features seafood Restaurants along coastal cities and villages offer dishes cooked with fresh seafood, crops, fruits and vegetables. Cooked in their own juices, they feature an originat flavor. People in the coastal villages along the Bohai and Huanghai seas lire on fishing with men going to sea while women take care of the household chores and wodk in the fields. Hard-boiled snakeheaded fish’s eggs and sea urchin soup are frequently served in the morning before men set out to sea According to folk legend, these dishes are believde to stop storms and give men courage to overcome difficulties The intervals men don’t go to展开更多
基金support by the Key Project of Nature Science Fund of Shandong Province, China (ZR2011B Z008)the Special Fund of Marine Renewable Energy from China’s State Oceanic Administration (GHME 2011GD04)
文摘Cathode activity plays an important role in the improvement of the microbial fuel cells on ocean floor （BMFCs）. A comparison study between Rayon-based （CF-R） and PAN-based carbon fiber （CF-P） cathodes is conducted in the paper. The two carbon fibers were heat treated to improve cell performance （CF-R-H ＆ CF-P-H）, and were used to build a new BMFCs structure with a foamy carbon anode. The maximum power density was 112.4mWm-2 for CF-R-H, followed by 66.6mWm-2 for CF-R, 49.7 mWm-2 for CF-P-H and 21.6mWm-2 for CF-P respectively. The higher specific area and deep groove make CF-R have a better power output than with CF-P. Meanwhile, heat treatment of carbon fiber can improve cell power, nearly two-fold higher than heat treatment of plain fiber. This improvement may be due to the quinones group formation to accelerate the reduction of oxygen and electron transfer on the fiber surface in the three phase boundary after heat treatment. Compared to PAN-based carbon fiber, Rayon-based carbon fiber would be preferentially selected as cathode in novel BMFCs design due to its high surface area, low cost and higher power. The comparison research is significant for cathode material selection and cell design.
基金supported by the Key Project of Natural Science Fund of Shandong Province (ZR2011BZ008)the Marine Renewable Energy Special Fund Project from the State Oceanic Administration PRC (GHME2011GD04)+2 种基金the Scientific and Technology Development Plan Project of Shandong Province,China (2008GG10007003)the Key Laboratory of Submarine Geoscience and Exploring Technology of the Ministry of Education,Ocean University of China (Grant No. 2008-01)the Key Laboratory of Marine Environment & Ecology,Ministry of Education (Grant No. 2008010)
文摘Microbial fuel cell(MFC) on the ocean floor is a kind of novel energy-harvesting device that can be developed to drive small instruments to work continuously.The shape of electrode has a great effect on the performance of the MFC.In this paper,several shapes of electrode and cell structure were designed,and their performance in MFC were compared in pairs:Mesh(cell-1) vs.flat plate(cell-2),branch(cell-3) vs.cylinder(cell-4),and forest(cell-5) vs.disk(cell-6) FC.Our results showed that the maximum power densities were 16.50,14.20,19.30,15.00,14.64,and 9.95 mWm-2 for cell-1,2,3,4,5 and 6 respectively.And the corre-sponding diffusion-limited currents were 7.16,2.80,18.86,10.50,18.00,and 6.900 mA.The mesh and branch anodes showed higher power densities and much higher diffusion-limited currents than the flat plate and the cylinder anodes respectively due to the low diffusion hindrance with the former anodes.The forest cathode improved by 47% of the power density and by 161% of diffusion-limited current than the disk cathode due to the former's extended solid/liquid/gas three-phase boundary.These results indicated that the shape of electrode is a major parameter that determining the diffusion-limited current of an MFC,and the differences in the elec-trode shape lead to the differences in cell performance.These results would be useful for MFC structure design in practical applica-tions.
文摘Extensive oedometer tests and physical tests have been conducted on remolded and reconstituted marine soils with different initial water contents and liquid limits. The oedometer test data can be well fitted with a straight line in the bilogarithmic ln(1+ e ) ～ lg p plot. The initial effective stress corresponding to the initial void ratio is determined by extrapolation of the bilogarithmic compression line. This new way of extrapolating oedometer test data to the initial void ratio overcomes the difficulty of measuring the residual effective stress of soils in the remolded state. The initial stable compression line of ocean floor deposits under different deposition environments corresponds to the compression line at the sensitivity equal to one. This initial stable compression line obtained in this study is consistent with the available compression line at the sensitivity equal to one which is proposed based on the experimental data of remolded undrained strength and the theoretical concept of Cam clay critical state line.
基金supported by the Scientific and Technological Development Plan Project of Shandong Province, China (2008GG10007003)the Key Laboratory of Marine Environment & Ecology, Ministry of Education (2008010)the Key Laboratory of Submarine Geoscience and Exploring Technology of Ministry of Education, Ocean University of China (2008-01)
文摘A unique sulfonated polyaniline/vanadate composite was synthesized and utilized as a composite anode in microbial fuel cells on ocean floor (BMFCs). X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were employed to characterize its chemical composition and morphology. Wettability of the composite anodes decreases due to the addition of polytetrafluoroethylene (PTFE). The electrochemical behavior of the composite anodes was investigated by means of linear sweep voltammetry and Tafel plot measurements. Compared with the plain graphite anode,the composite anode significantly improves the power density,5.5-fold higher,reaching 187.1 mW/m2 and gives a 27-fold higher exchange current density and a higher kinetic activity. A novel synergistic mechanism between sulfonated polyaniline and vanadate is proposed to explain the excellent electrochemical performance. This composite thus has great potential to be used as an anode material for a high-power BMFC.
文摘人们曾经一度担心:当深埋在地下的最后一滴石油用尽之后,人类将 如何发展.甚至如何生存。读了本文,也许你会觉得“杞人忧天”并非古人的故事。新一代的能源已经显露在地平线上。它正lie frozen in combustible(易燃的)ice crystals(晶体)below the ocean floor. 它的名称尚未确定:gas or methane(甲烷)hydrates(水合物;氢氧化物)。 人们如此推测它的由来:organic(有机体的)sediments(沉淀物)have beentrapped for many millions of years by pressure and cold. 这种新能源估计投入商业开采的年限是:15 years may be a reasonable goal“for commercial extraction”. 目前,世界油价连连飞涨,世界经济也深受影响,在此大背景下,这则消息就越发显得令人兴奋不已: While research is at an early stage—just compiling a round inventory(总量)of hydrate formations around the world will take decades—excitement is buildingand some scientists,including officials at the U.S.Energy Department,believelarge—scale commercial exploitation could begin by 2015.化理想为现实,变荒野为坦途,困难和问题一定会接踵而来,但是,在人类的历史上,希望实现总是不可阻挡的。
文摘SHANDONG Province harbors one of the ten maior families of dishes in China—the Lu-stvle of foed Located next to the Bohai Sea. Shandong Province is filled with many tasty sea treats. There are two branches of Lu-style food, The dishes popnlar in inner Shandong contain mostly poultry. meat and internat organs of animals. The other branch of Lu-style food, popular in the coastal area features seafood Restaurants along coastal cities and villages offer dishes cooked with fresh seafood, crops, fruits and vegetables. Cooked in their own juices, they feature an originat flavor. People in the coastal villages along the Bohai and Huanghai seas lire on fishing with men going to sea while women take care of the household chores and wodk in the fields. Hard-boiled snakeheaded fish’s eggs and sea urchin soup are frequently served in the morning before men set out to sea According to folk legend, these dishes are believde to stop storms and give men courage to overcome difficulties The intervals men don’t go to
