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To solve the problems of EDM when using the ordinary fluid and mold manufacturing, this paper provides the orthogonal experiment in the suspended powder fluid, which can optimize the main process parameters. And it also achieves t...
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To solve the problems of EDM when using the ordinary fluid and mold manufacturing, this paper provides the orthogonal experiment in the suspended powder fluid, which can optimize the main process parameters. And it also achieves the technology of EDM in the suspended powder fluid primarily.
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Purpose: To optimize the extraction process of vitamin C from durian endocarp, and to determine the content of vitamin C in durian endocarp with high performance liquid chromatography (HPLC). Method: Optimize ultrasonic extraction...
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Purpose: To optimize the extraction process of vitamin C from durian endocarp, and to determine the content of vitamin C in durian endocarp with high performance liquid chromatography (HPLC). Method: Optimize ultrasonic extraction conditions by L9 (43) orthogonal experiment by using octadecylsilane chemically bonded silica as the stationary phase, using methanol (A): 0.1% oxalic acid (B) = 5:95 (V/V) as the mobile phase, setting the flow rate as 1.0 mL/min, and setting the wavelength as 254 nm for assay. Result: The optimal extraction process is as follows: the material-liquid ratio is 1:12, the extraction solvent is 2% oxalic acid aqueous solution, and the extraction time is 30 min;Vitamin C has a good linearity within the concentration range of 5.4 - 108.0 mg·mL-1, and the regression equation is y = 37698x - 61035 (R2 = 0.9996);the average recovery rate is 99.03%, the instruments are of high precision with good stability. Conclusion: This extraction process performs well in simplicity, costs and extraction efficiency, which may accelerate the development and utilization of vitamin C extraction from durian endocarp, and provide references to relevant studies and practices.
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Based on the quality analysis of the medium carbon product whose grade was 81%-82%, the emphasis of the study was placed on the orthogonal experiments of roughing flotation reagent and single factors, such as abrasive grain, pulp ...
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Based on the quality analysis of the medium carbon product whose grade was 81%-82%, the emphasis of the study was placed on the orthogonal experiments of roughing flotation reagent and single factors, such as abrasive grain, pulp concentration and the rotating speed of floatation machine. The result with improvement in the grade of concentrate to 95% through the routine floatation method was achieved.
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Terpolymer demulsifier of acryl resin has been synthesized through solution polymerization with water as a dissolvent,potassium persulfate as an initiator and the monomers of methyl methacrylate,butyl acrylate and acrylic acid as ...
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Terpolymer demulsifier of acryl resin has been synthesized through solution polymerization with water as a dissolvent,potassium persulfate as an initiator and the monomers of methyl methacrylate,butyl acrylate and acrylic acid as starting materials.The effects of the reaction temperature,dripping time,the amount of monomers and initiator on the dehydration rate of the demulsifier were investigated by an orthogonal experiment.It shows that the stronger influence on the dehydration rate among six factors is reaction temperature,dripping time,and amount of catalyst,while monomer has weak influence.The performance of the demulsifier was evaluated under different demulsification time,temperatures and concentrations of the screened demulsifiers.The result shows that the dehydration rate of the demulsifier can reach over 67%,which is better than that by the emulsion polymerization way.
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Different series of transition metal catalysts supported on Al2O3 were prepared by the impregnation method. The catalytic activity was measured in a batch reactor with ozone as the oxidizing reagent. The experimental results indic...
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Different series of transition metal catalysts supported on Al2O3 were prepared by the impregnation method. The catalytic activity was measured in a batch reactor with ozone as the oxidizing reagent. The experimental results indicate that Cu/Al2O3 has a very effective catalytic activity during the ozonation of organic pollutants in water. The optimum conditions for preparing Cu/Al2O3 were systematically investigated with the orthogonal testing method. Furthermore, the results also show that the surface properties of catalyst are not compulsory for effective oxidation.
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The Fenton oxidation process was applied in the treatment of an actual high concentration nonylphenol Ethoxylates (NPEOs) wastewater. The effects of H2O2 dosage, molar ratio of H2O2/Fe2+ (Fe2+ dosage), pH value and reaction time o...
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The Fenton oxidation process was applied in the treatment of an actual high concentration nonylphenol Ethoxylates (NPEOs) wastewater. The effects of H2O2 dosage, molar ratio of H2O2/Fe2+ (Fe2+ dosage), pH value and reaction time on the degradation of NPEOs were investigated. The orthogonal experiment indicated that the order of degree of influence on the COD removal was molar ratio of H2O2/Fe2+, reaction time, dosage of H2O2, and initial pH. The single-factor tests were carried out to determine the optimal conditions, and the results were H2O2 dosage of 76.32 mmol/L, molar ratio of H2O2/Fe2+ of 3, pH value of 5 and reaction time of 2 h. Under the optimum operation conditions, the COD removal efficiency was 85.6% and the effluent could be mixed with other wastewater into the large-scale biological treatment system.
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Aiming to ease the cutting of kenaf stalks via bionics,the bionic disc cutter was designed.The upper jaw of the Batocera horsfieldi was used as a bionic prototype.Further,to explore its dynamic performance,an indoor multi-stalk cu...
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Aiming to ease the cutting of kenaf stalks via bionics,the bionic disc cutter was designed.The upper jaw of the Batocera horsfieldi was used as a bionic prototype.Further,to explore its dynamic performance,an indoor multi-stalk cutting experimental bench was used to simulate the field operation process.A three-factor and two-level interaction orthogonal experiment was carried out;cutting speed,stalk conveying speed(machine forward speed),and blade type(ordinary disc cutter and bionic disc cutter)were used as experiment factors.The cutting pass rate and cutting specific energy consumption were selected as evaluation indexes.The range,variance,and fuzzy comprehensive evaluation analysis were carried out on the experiment results.Moreover,the main order factors affecting the bionic cutter performance were determined-blade type,conveying speed,the interaction between the cutter speed and conveying speed,and cutter speed.The optimal parameter combination scheme had a cutter speed of 1000 r/min,conveying speed of 0.4 m/s,and included bionic blades.Under this condition,the best index was the 92%cutting pass rate,with a specific energy consumption of 4.38 J/stalk.The variance analysis has shown that,with 95%confidence,the blade type has a rather significant influence on the comprehensive index.Additionally,the conveying speed also significantly influenced it,while other factors and interactions had no notable effect.The experimental comparison under the same working condition shows that the bionic blade has better cutting effect.This study provides a reference for the development of cutter and the selection of kenaf harvester operational parameters.
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