Papers by Keyword: Orthogonal Test

Abstract: At present, adding solid waste in plant substrate to replace part of planting soil has become a new direction in the field of ecological slope protection substrate research. In this paper, 16 groups of indoor orthogonal experiments were carried out with fly ash and sludge as the components of vegetation substrate and tall fescue as the planting object to explore the influence of ecological slope protection substrate on vegetation growth. Based on the range analysis method, the three functions of substrate planting performance, mechanical properties and substrate properties were used as references, and the entropy weight method (EWM) was used to assign weights to the proportion of each index in the total score, and the ratio was optimized. The results show that the optimal substrate ratio is 10% sludge content, 30% fly ash, 4% cement, 6% fiber, 50% planting soil (the ratio of loess and peat soil is 1:3). Fly ash has a great influence on the height of plants and vegetation coverage, and has a significant effect on the internal friction angle and fertility of the substrate. Sludge mainly affects the growth height of plants and the pH value and fertility of the substrate. The importance of factors affecting the growth of plants from large to small is: fly ash, the ratio of loess and peat soil, sludge, rice husk, cement.

Abstract: In this paper, a thermal inkjet printing simulation model is established in the CFD simulation platform, and the influence of inkjet driver parameters and ink physical parameters on the printing process is studied by numerical simulation. The evaporation-condensation model is coupled with the VOF multiphase flow model in Fluent software to establish a thermal inkjet printing process simulation model. Based on the orthogonal test method, we investigate the influence of fluid physical parameters (ink viscosity, surface tension) and inkjet driver parameters (heater temperature value) on droplet formation by changing the physical parameters of the material and the boundary conditions of the model. Through the comparison of the results, exploring the adjustment rules of thermal inkjet technology and obtaining the optimal combination of material and process parameters for high-quality ink drop formation.

Abstract: Geopolymer-based plant fiber composites were fabricated with metakaolin, alkaline sodium silicate and plant fibers. In this paper, orthogonal test and single factor analysis were used to study the influence of water glass modulus, solid liquid ratio and fiber content on bending strength. The results show that sequence of influence factors for bending strength was: solid to liquid ratio > fiber content > water glass modulus. When the water glass modulus is 1.7, the fiber content is 8% and the solid to liquid ratio is 1:1.4, the bending strength is up to 10.44MPa, which exceeds the Standard requirements (9MPa) specified by the China National Standard (GB/T 24312-2009). The micro-morphology of SEM indicates that the mix of plant fiber can enhance the toughness of geopolymer.

Abstract: Se-polysaccharides are organic Se-conjugated biological macromolecules with stronger biological activities than Se-free polysaccharides. Se-polysaccharides, as a kind of biological materials, can be extracted from Se-enriched tea and can increase the added value of tea production. Microwave–ultrasonic synergistic extraction exhibits the advantages of microwave and ultrasonic extraction and thus provides an economic and effective path for utilization of Se-polysaccharides. In this study, Se-polysaccharides were extracted from Se-enriched tea by microwave–ultrasonic synergistic method for the first time. The optimal condition was determined through single-factor experiment and L₉(4³) orthogonal experiment. Results showed that the optimal condition comprised the following: ratio of solvent to material of 20:1, microwave power of 250 W, extraction temperature of 60 °C, and extraction time of 210 s; under this condition, the extraction rate of Se-polysaccharides reached the maximum value of 4.56%. This study shows that microwave–ultrasonic synergistic extraction is an efficient technology for extracting Se- polysaccharides from Se-enriched tea.

Abstract: Effects of polyvinylchloride (PVC) sheet thickness (t), feed speed (υ), spindle speed (ω), Z-axis feed rate (p) and tool head diameter (Φ) as well as their interactions during the single point incremental forming (SPIF) on forming performance of the PVC sheet material were studied through an orthogonal experimental test. In this experiment, the angle-variable cone was used and the maximum forming limiting angle was taken as the experimental index. Results showed that and ω×Φ influence forming performance of PVC sheet material significantly. υ is the main influencing factor of SPIF performance of PVC sheet material. Small υ is good for sheet material forming. p and Φ are proportional to forming performance of sheet material. Over ω will cause material wear-out. Effect of t could be neglected.

Abstract: An orthogonal hardness study of 4 factors (the step one aging temperature (T1) and time (t1), and step two aging temperature (T2) and time (t2)) with 3 levels was designed to optimize an accelerated aging process for a newly developed conductive aluminum alloy (Al-0.4wt.%Si-0.3wt.% Mg-0.3wt.%Ce). Statistical analysis of the experimental results indicates that the factor significance ranked from high to low is t2, T2, T1, and t1. The optimal aging process is 140°C×5h+220°C×5h. Experimental validation confirms that all the strength, hardness, elongation and conductivity with the optimized aging process exceed the predictions. Compared with the commonly used T7 process (190°C×20h), the optimized aging process leads to a more superior precipitation effect and much less time. TEM observation indicates the accelerated aging process significantly expedites the precipitating transformation even with much shorter aging time.

Abstract: An amorphous Ni-Fe-P alloy coated shielding fabric with dense uniform coating was prepared by conducting electrical deposition of amorphous Ni-Fe-P alloy on copper-coated polyethylene terephthalate (PET) fabric. This research investigated the preparation process by using orthogonal test with 8 factors and 3 levels. It analyzed the influences of components of the plating solution on the ohms per square, weight gain rate, and shielding effectiveness of coating. Besides, the morphology, composition, and structure of the coating were analyzed by using Scanning Electron Microscope (SEM), Energy Dispersive Spectrdmeter (EDS), and X-ray Diffraction (XRD). The shielding effectiveness of the alloy fabric was also tested. The results indicated that the processing conditions of the amorphous Ni-Fe-P alloy coated fabric using electrical deposition consisted of 135 g/L of NiSO₄•6H₂O, 105 g/L of FeSO₄•7H₂O, 8 g/L of NaH₂PO₂•H₂O, 24 g/L of C₆H₈O₆, 36 g/L of C₆H₈O₇, 22 g/L of H₃PO₃, 65°C, pH=1.5, and current density =13 A/dm². The fabric obtained in the paper presented compact, smooth, and uniform coating with fine crystal. The coating was the amorphous Ni-Fe-P alloy with 18.67% of P (mass fraction). The shielding effectiveness of this coated fabric reached to 60.82 dB-73.63 dB in a broad frequency range of 300 kHz-1.5 GHz.

Abstract: . Based on orthogonal test, the forming accuracy and density of laser sintering eucalyptus/PES blend is studied in this paper. It mainly analysed the effect of the powder size and process parameters (such as laser power, layer thickness, preheating temperature, etc) on the forming precision and density of sintered eucalyptus/PES parts, also the correlation analysis of molding error caused by the powder’s physical properties and machine is performed. By measuring the parts’ dimensions, the results show that the laser power and powder size are two main factors influencing parts’ density, and variable density, layer thickness and preheating temperature jointly affect the dimensional accuracy. The optimized processing parameters are obtained. The powder size, laser power, scanning rate, layers thickness and preheating temperature are 300 mesh, 43W, 2000mm/s, 0.1mm, 60°C respectively.

Abstract: The influence of different factors in the alcogel preparation process and ambient pressure drying process on packing density of hydrophobic TiO₂ aerogel synthesized by ambient pressure drying (APD) and the optimum preparation conditions were investigated by the orthogonal test with four-factor and three-level L₉(3⁴), respectively. The morphology and structural properties of hydrophobic TiO₂ aerogels with different density were characterized by Fourier Transform Infrared Spectroscopy (FT-IR), Thermogravimetry (TG), N₂ adsorption-desorption measurement and Scanning Electron Microscope (SEM). The results showed that the most important factors in the preparation process for TiO₂ aerogels with low-density under ambient pressure are aging time, the volume ratio of C₂H₅OH to TBT, ethanol immersion time and hydrophobic modification time. The optimized preparation conditions are that aging time is 24 h, the volume ratio of C₂H₅OH to TBT is (7+7) : 5, the volume ratio of H₂O to TBT is 1.7 : 5, the volume ratio of HAc to TBT is 1.7 : 5, ethanol immersion time is 24 h, hydrophobic modification time is 48 h, hexane solvent replacement time is 24 h and the drying temperature is 393 K. TiO₂ aerogels with density of 460 kg/m³ was obtained at the optimized conditions. TiO₂ aerogel with lower density displays higher specific surface area, porosity and pore volume as well as the larger pore size.

Abstract: Following with the development of construction industry, small diameter anti-sliding pile has been widely implemented in slope stabilization and deep foundation support. Much attention has been paid on researching lateral resistance of pile body. By orthogonally testing factors of small diameter anti-slide reinforcement pile models including concrete strength, sectional dimension and reinforcement bar gauge, The article analyzed sensitive influence to lateral resistance of pile body. The results indicate that concrete strength appears the most sensitive factor, next sectional dimension, and then reinforcement bar gauge. By comparing with shearing test of small diameter anti-slide reinforcement pile models, the conclusion follows that reinforcement of pile body does not fully unleash its shear resistance characteristic. Thus conclusion provides reference for implementation and designing of small diameter anti-slide pile.