Papers by Keyword: Orthogonal Experiment

Abstract: Orthogonal experiment optimization of microwave-assisted extraction (MAE) conditions of total flavonoids from castor leaves with the factors of ethanol concentration, microwave power, extraction time, solid/liquid ratio on the yield of total flavonoids were studied. The results showed that optimum extracting conditions of total flavonoids from castor leaves were as follows: adding 1:50 g·mL-1 of 40% alcohol and extracting for 3 min,microwave irradiation power 464W. Microwave extraction of total flavonoids from castor leaves is fast, energy saving and high extraction rate.

Abstract: The preparation of lactic acid (LA) from the conversion of carbohydrates through chemical ways has received much attention as a way of producing platform chemicals from renewable resources, but harsh reaction conditions were usually employed especially when environmentally benign solvent (water) was used as the reaction media. In this work, polymerizates of imidazole and epichlorohydrin ([IMEP]Cl) have been used as catalysts for the conversion of maltose to LA. Several factors, including the temperature, the NaOH concentration, the [IMEP]Cl loading and the maltose concentration, were found to affect LA yield, and the process was optimized by method of orthogonal experiment. The order of significant factors was found to be maltose concentration > temperature > [IMEP]Cl loading > NaOH concentration. The optimum yield of LA was 48.5%. This route provides a new strategy for carbohydrates conversion to produce fine chemicals.

Abstract: Al₂O₃ ceramics are widely used in aerospace, defense industry, microelectronics industry and many other fields, but the precision machining methods of this material are restricted because of the high hardness. Therefore, this paper makes an orthogonal experiment of high-speed micro-milling Al₂O₃ ceramics by machining full-diameter micro-grooves. The feasibility of micro-milling Al₂O₃ ceramics with diamond coated tools is verified. In the experiment, surface roughness values obtained are treated as evaluation indexes. And the influences of many process parameters on the workpiece surface roughness are analyzed by range analysis method. These parameters are spindle speed, feed rate and axial depth of cut. Then optimized the process parameters and obtained a set of suitable parameters to micro-mill Al₂O₃ ceramics.

Abstract: It had decades of history that cementing material was used for filling in coal mine or metal mine goaf, which was a common filling material in recently filling mining. Paste and high water material have excellent performance, but the price was too high, which restricted the development of cemented filling technology severely. Later, fly ash and other industrial waste were mixed into the cementing material in order to reduce the cost, but because of which early activity was low, the early strength was reduced by mixing too much fly ash and other industrial waste, the setting time was extended, which affected the filling effect seriously. Therefore, it becomes a key problem that how to excite the early activity of fly ash. It was a breakthrough to select the appropriate activator and activation method, because of the difference mechanism of action and effects for different activators of fly ash, the complexity composition of filling material mixed with large number of fly ash, and the early and late physical and mechanical properties [1,2].Four salts are used for activators in this paper, which are mixed with fly ash and water, and a display method was selected to maximum activate the activity of fly ash, increase the early strength of the material, and reduce the cost of the material.

Abstract: Orthogonal experiment optimization of adsorption conditions with the factors of pH value, adsorption time, adsorbent amount of brilliant cresyl blue wastewater by brewer's grains were studied. The results showed that optimum adsorption conditions were as follows: 100 mL brilliant cresyl blue dye solution of 150 mg·L^-1,adding 5.0 g·L^-1brewer's grains of 60~80 mesh and adsorbed for 2.0 h,extraction temperature 30°C,pH 5.0. Under the optimal conditions, the maximal absorption rate got 95.12%.The brewer's grains is a promising, cheap, efficient, new biological materials of adsorption for brilliant cresyl blue in wastewater.

Abstract: According to the principle of Preparation about Reactive powder concrete (RPC),selection of local raw materials,the use of orthogonal experimental design method,carried out research of RPC mixing proportion design. Finally get the RPC optimal mix of meeting engineering requirement. By the range analysis and variance analysis of the test data of mix,obtained the influence law about water-cement ratio,steel fiber content, sand type,curing regime on compressive strength and splitting tensile strength .

Abstract: Autonomous coal fly ash modified by vitriol (H₂SO₄) was used to treat Phenol Waste Water. The treatment influences were determined by single-factor experiment and the prioritizing importance and optimizing combination of the influences were studied using orthogonal experiment. We found that the prioritizing importance of the influencing factors was as follow: dosage of ferrous sulfate (FeSO₄) > dosage of hydrogen peroxide (H₂O₂) > initial concentration of phenol > PH > the dosage of modified coal fly ash. The optimizing combination of the influences was 5 wt.% FeSO_4, 1 mL ; 3 wt.%H₂O₂, 7 mL; PH=5; initial concentration of phenol , 300 mg/L and the dosage of modified coal fly ash, 200 mg/L. Under the condition above, phenol removal rate was 99.46%.

Abstract: An effective method for decolorization of the polysaccharides from Lethariella spp. was studied. Decolorization rate was used as an indicator in the experiment, single factor text and orthogonal experiment was used to get the optimal conditions, the single factor experiment was carried out with temperature at 35°C, 45°C, 55°C, 65°C, and 75°C, the activated carbon added at 0.5%, 1%, 1.5%, 2%, and 2.5%, and time at 10, 15, 20, 25, and 30min, respectively. The optimal conditions of Lethariella spp. clarification using activated carbon were carried out to get the optimal conditions (the temperature at 55°C, the activated carbon added at 1%, and time was 25 min, and the decolorization rate could reach 57.56 %).

Abstract: There are many advantages in producing forklift box through the LFC. However, we found shrinkage porosity defects in the interior of castings through simulating the original process by ProCAST casting simulation software. Therefore, we analyzed the defects and improved the technology program. firstly, increased riser in position of shrinkage, Secondly, changed the filling’s way, lastly, selected the best temperature and vacuum by the orthogonal experiment and determined the best technology solution. we found the shrinkage porosity defects have been removed by the improved process. We found the production consistent with the simulation results through verification. Therefore we verify the accuracy of the ProCAST.

Abstract: A new vacuum assisted extraction (VAE) method was established and applied for the extraction of indirubin from Radix Isatidis. The major factors of VAE process such as boiling temperature, ethanol level, extraction time and extraction cycles, which have influence on the extraction yield of indirubin were tested by an orthogonal array L₉ (3⁴).The results show that the optimum extraction conditions are ethanol level 40% (v/v), boiling temperature 60 °C, extraction time 3 h and extraction 3 cycles. Under these conditions the extraction efficiency of indirubin reaches 1.091 mg/g, which is 30% higher than that by conventional heat reflux extraction at atmospheric pressure. The present results demonstrated that VAE is an efficient, simple and fast method for extracting indirubin from Radix Isatidis, which shows great potential for becoming an alternative technique for industrial scale-up applications.