The main objective of this research was to study the removal of turbidity and COD (chemical oxygen demand) from a synthetic water sample. The water sample was treated chemically by coagulation. Two inorganic coagula...The main objective of this research was to study the removal of turbidity and COD (chemical oxygen demand) from a synthetic water sample. The water sample was treated chemically by coagulation. Two inorganic coagulants were used, ferric chloride and the double salt potassium-aluminium sulphate. The optimum coagulant dosage and working pH were examined. The results for ferric chloride as coagulant showed that the maximum removal efficiency (%) of COD was achieved at pH 6 with a dosage of 100 mg-L-1 and the maximum removal efficiency (%) of turbidity at pH 5 with a dosage of 500 mg.L-1. For double salt, as coagulant, the maximum removal efficiencies (%) of COD and turbidity were achieved at pH 6 with a dosage of 3,500 mg.L-1. An extensive comparison with results from previous studies was also described in this research.展开更多
In situ surface synthesis of Ca–Mg–Al hydrotalcite(HT) on inorganic ceramic membrane(CM) was investigated with urea as precipitator. The effects of molar ratio of raw materials, crystallization time, and temperature...In situ surface synthesis of Ca–Mg–Al hydrotalcite(HT) on inorganic ceramic membrane(CM) was investigated with urea as precipitator. The effects of molar ratio of raw materials, crystallization time, and temperature on surface synthesis of HT were examined. The as-prepared HT/CM samples were characterized by XRD and SEM and an in situ growth mechanism of HT on CM was proposed. KF/HT/CM obtained by loading potassium fluoride(KF) on the HT layer by impregnation and calcination method was used as catalyst for transesterification between palm oil and methanol. The comparison of KF/HT/CM and pure KF/HT powder under identical reaction conditions shows that the production of fatty acid methyl ester is equivalent, which means that the use of inorganic catalytic membrane in the transesterification is a viable alternative.展开更多
The paper aims to challenge non-GPS navigation problems by using visual sensors and geo-referenced images. An area-based method is proposed to estimate full navigation parameters(FNPs), including attitude, altitude an...The paper aims to challenge non-GPS navigation problems by using visual sensors and geo-referenced images. An area-based method is proposed to estimate full navigation parameters(FNPs), including attitude, altitude and horizontal position, for unmanned aerial vehicle(UAV) navigation. Our method is composed of three main modules: geometric transfer function, local normalized sobel energy image(LNSEI) based objective function and simplex-simulated annealing(SSA) based optimization algorithm. The adoption of relatively rich scene information and LNSEI, makes it possible to yield a solution robustly even in the presence of very noisy cases, such as multi-modal and/or multi-temporal images that differ in the type of visual sensor, season, illumination, weather, and so on, and also to handle the sparsely textured regions where features are barely detected or matched. Simulation experiments using many synthetic images clearly support noise resistance and estimation accuracy, and experimental results using 2367 real images show the maximum estimation error of 5.16(meter) for horizontal position, 9.72(meter) for altitude and 0.82(degree) for attitude.展开更多
The most used method for preparation of zeolites is hydrothermal synthesis from silicate or aluminosilicate gels at temperatures in the range of 60-200 ℃. Excess water used in the industrial process results in severa...The most used method for preparation of zeolites is hydrothermal synthesis from silicate or aluminosilicate gels at temperatures in the range of 60-200 ℃. Excess water used in the industrial process results in several issues, including high autogeneous pressure, low efficiency, pollution, etc. To solve these problems, several strategies have been developed. This review describes the solvent-free synthesis of zeolites. The combination of solvent-free synthesis and organotemplate-free synthesis can open the pathway to a highly sustainable zeolite synthesis protocol in industry.展开更多
文摘The main objective of this research was to study the removal of turbidity and COD (chemical oxygen demand) from a synthetic water sample. The water sample was treated chemically by coagulation. Two inorganic coagulants were used, ferric chloride and the double salt potassium-aluminium sulphate. The optimum coagulant dosage and working pH were examined. The results for ferric chloride as coagulant showed that the maximum removal efficiency (%) of COD was achieved at pH 6 with a dosage of 100 mg-L-1 and the maximum removal efficiency (%) of turbidity at pH 5 with a dosage of 500 mg.L-1. For double salt, as coagulant, the maximum removal efficiencies (%) of COD and turbidity were achieved at pH 6 with a dosage of 3,500 mg.L-1. An extensive comparison with results from previous studies was also described in this research.
基金Supported by the National Natural Science Foundation of China(21276050 and21406034)the National Basic Research Program of China(2010CB732206)
文摘In situ surface synthesis of Ca–Mg–Al hydrotalcite(HT) on inorganic ceramic membrane(CM) was investigated with urea as precipitator. The effects of molar ratio of raw materials, crystallization time, and temperature on surface synthesis of HT were examined. The as-prepared HT/CM samples were characterized by XRD and SEM and an in situ growth mechanism of HT on CM was proposed. KF/HT/CM obtained by loading potassium fluoride(KF) on the HT layer by impregnation and calcination method was used as catalyst for transesterification between palm oil and methanol. The comparison of KF/HT/CM and pure KF/HT powder under identical reaction conditions shows that the production of fatty acid methyl ester is equivalent, which means that the use of inorganic catalytic membrane in the transesterification is a viable alternative.
文摘The paper aims to challenge non-GPS navigation problems by using visual sensors and geo-referenced images. An area-based method is proposed to estimate full navigation parameters(FNPs), including attitude, altitude and horizontal position, for unmanned aerial vehicle(UAV) navigation. Our method is composed of three main modules: geometric transfer function, local normalized sobel energy image(LNSEI) based objective function and simplex-simulated annealing(SSA) based optimization algorithm. The adoption of relatively rich scene information and LNSEI, makes it possible to yield a solution robustly even in the presence of very noisy cases, such as multi-modal and/or multi-temporal images that differ in the type of visual sensor, season, illumination, weather, and so on, and also to handle the sparsely textured regions where features are barely detected or matched. Simulation experiments using many synthetic images clearly support noise resistance and estimation accuracy, and experimental results using 2367 real images show the maximum estimation error of 5.16(meter) for horizontal position, 9.72(meter) for altitude and 0.82(degree) for attitude.
基金supported by the National Natural Science Foundation of China(21273197,21333009,21203165)Fundamental Research Funds for the Central Universities(2013XZZX001)+1 种基金the National High Technology Research and Development Program of China(2013AA065301)the Science and Technology Innovative Team of Zhejiang Province(2012R10014-02)
文摘The most used method for preparation of zeolites is hydrothermal synthesis from silicate or aluminosilicate gels at temperatures in the range of 60-200 ℃. Excess water used in the industrial process results in several issues, including high autogeneous pressure, low efficiency, pollution, etc. To solve these problems, several strategies have been developed. This review describes the solvent-free synthesis of zeolites. The combination of solvent-free synthesis and organotemplate-free synthesis can open the pathway to a highly sustainable zeolite synthesis protocol in industry.