scholarly journals Theoretical and Experimental Studies on Air-suction Roller-type Precision Seed-Metering Device

2021 ◽  
Vol 2087 (1) ◽  
pp. 012047
Author(s):  
Huiping Si ◽  
Chunyuan Zhang ◽  
Kaiyan Lin ◽  
Yusheng Wu ◽  
Junhui Wu
Keyword(s):  
Rotation Rate ◽  
Experimental Studies ◽  
Equation Of Motion ◽  
Orthogonal Test ◽  
Single Factor ◽  
Optimization Analysis ◽  
Experimental Parameters ◽  
Predicted Values ◽  
Seed Metering Device

Abstract The seed-metering device is the key component of a precision seeder. The methods to improve the seed suction and dropping efficiency of air suction drum precision seed metering device were discussed Establishing the force and equation of motion for sucking, carrying and dropping stages, the effect of the seeding parameters on the effect of sucking and seeding is analyzed. Then, the single factor and orthogonal test are carried out on the sucking pressure, the carrying pressure, the rotation rate and the dropping pressure as the experimental factors for the optimization analysis. And the optimum experimental parameters and the predicted values of each test index are obtained. That is, when the seeding pressure of -2.87kPa, the seeding pressure of -1.91kPa, the drum rotation rate of 18.72 r min-1 and the dropping pressure of 1.74kPa, the best effect that the single rate is 93.8%.

scholarly journals Characterization and optimization of spectrophotometric colour removal from dye containing wastewater by Coagulation-Flocculation

2018 ◽  
Vol 20 (4) ◽  
pp. 49-59 ◽  
Author(s):  
I.A. Obiora-Okafo ◽  
O.D. Onukwuli
Keyword(s):  
Removal Efficiency ◽  
Contour Plot ◽  
Process Conditions ◽  
Optimization Analysis ◽  
Colour Removal ◽  
Coagulant Dosage ◽  
Main Effect ◽  
Ftir Spectrometer ◽  
Predicted Values ◽  
Central Composite

Abstract The performance of Vigna unguiculata coagulant (VUC) for colour removal from acid dye was investigated in this study. The proximate, structure and morphology of the coagulant were investigated using standard official methods, Fourier-Transform Infrared (FTIR) spectrometer and scanning electron microscopy (SEM), respectively. Response surface methodology (RSM) using face-centred central composite design (FCCD) optimized four process variables including pH, coagulant dosage, dye concentration and time. The colour removal efficiency obtained from the optimization analysis was 99.26% at process conditions of pH 2, coagulant dosage 256.09 mg/l, dye concentration 16.7 mg/l and time 540 min. The verification experiments agreed with the predicted values having a standard error value of 1.96%. Overlay contour plot established optimum areas where the predicted response variable is in an acceptable range (≥ 70%) with respect to optimum conditions. The FCCD approach was appropriate for optimizing the process giving higher removal efficiency when compared to the main effect plots.

Fractal and Non-Fractal Surfaces in Ion Sputtering

1995 ◽  
Vol 407 ◽  
Author(s):  
A.-L. Barabási ◽  
R. Cuerno
Keyword(s):  
Nonlinear Equation ◽  
Penetration Depth ◽  
Experimental Studies ◽  
Ion Bombardment ◽  
Physical Parameters ◽  
Angle Of Incidence ◽  
Ion Sputtering ◽  
Scaling Properties ◽  
Fractal Surfaces ◽  
Experimental Parameters

ABSTRACTRecently a number of experimental studies focusing on the scaling properties of surfaces eroded by ion bombardment provided apparently contradictory results. A number of experiments report the observation of self-affine fractal surfaces, while others provide evidence about the development of a non-fractal periodic ripple structure. To explain these discrepancies, here we derive a stochastic nonlinear equation that describes the evolution and scaling properties of surfaces eroded by ion bombardment. The coefficients appearing in the equation can be calculated explicitly in terms of the physical parameters characterizing the sputtering process. We find that transitions may take place between various scaling behaviors when experimental parameters, such as the angle of incidence of the incoming ions or their average penetration depth, are varied.

Optimization of Extraction Conditions of Essential Oil from Latifolia miq Roots and Stems with Supercritical CO2 Fluid

2013 ◽  
Vol 726-731 ◽  
pp. 4512-4516
Author(s):  
Ren Yong Gu ◽  
Zhi Ping Li
Keyword(s):  
Essential Oil ◽  
Optimum Condition ◽  
Raw Materials ◽  
Extraction Process ◽  
Orthogonal Test ◽  
Single Factor ◽  
Extraction Condition ◽  
Optimum Extraction ◽  
Optimum Extraction Condition

Studying on the extraction process of essential oil from Latifolia Miq roots and stems by Supercritical CO2 extraction. The effects on extracting ratio were investigated by using single factor test, adding content of grinding fineness of raw materials,extracting temperature, extracting pressure and extracting time. The optimum extraction condition was determined by orthogonal test. The results showed that the optimum condition of the extraction was as follows: grinding fineness 90 mesh, extracting temperature 45 °C, extracting pressure 20 MPa and extracting time 2.5 h.

The Impact of Bedside Technology on Patients' Well-Being

2011 ◽  
Vol 5 (1) ◽  
pp. 43-51 ◽  
Author(s):  
Karin Tanja-Dijkstra
Keyword(s):  
Medical Equipment ◽  
Emotional State ◽  
Healing Process ◽  
Experimental Studies ◽  
Well Being ◽  
Single Factor ◽  
Healthcare Design ◽  
Healthcare Environment ◽  
The Impact ◽  
Insight Into

Objective: This paper presents a study to gain insight into the effects of the visibility of medical equipment on the well-being of patients. Background: Encounters with healthcare situations are characterized by stress and anxiety. The presence of wires, tubes, and monitors near the bedside may contribute to these feelings. One of the trends in healthcare design is to organize the headwalls of patient rooms in such a way as to reduce clutter and minimize the visibility of medical equipment, but no experimental studies are available that investigate the effects of the visibility of medical equipment in patient rooms. Methods: This experiment employed a single-factor between-subjects design (medical equipment visible vs. medical equipment out of sight) exposing participants ( n = 42) to a scenario and a picture of a hospital room. Results: Placing medical equipment out of sight leads to reduced feelings of stress in patients. This stress-reducing effect is mediated by feelings of pleasure. Placing medical equipment out of sight leads to a more positive emotional state, which in turn leads to feelings of reduced stress in patients. Moreover, placing equipment out of sight leads to people having more trust in the healthcare provider. Conclusions: The current study emphasizes the importance of the built healthcare environment and shows what role the visibility of medical equipment can play in the healing process of patients.

scholarly journals A Model of Brain Arteriolar Oxygen and Carbon Dioxide Transport during Anemia

1993 ◽  
Vol 13 (5) ◽  
pp. 872-880 ◽  
Author(s):  
Richard S. Schacterle ◽  
Robert J. Ribando ◽  
J. Milton Adams
Keyword(s):  
Carbon Dioxide ◽  
Mathematical Model ◽  
Blood Flow ◽  
Tissue Oxygenation ◽  
Normal Values ◽  
Experimental Studies ◽  
Limited Information ◽  
Carbon Dioxide Transport ◽  
Theoretical Evidence ◽  
Predicted Values

Existing experimental and theoretical evidence suggests that precapillary diffusion of O2 and CO2 occurs between arterioles and tissue under normal physiologic conditions. However, limited information is available on arteriolar gas transport during anemia. With use of a mathematical model of an arteriolar network in brain tissue, anemic hematocrits of 35, 25, and 15% were modeled to determine the effect of anemia on the exchange, the change in the equilibrium tissue O2 and CO2 tensions, and the increase in blood flow needed to restore tissue oxygenation. We found that the blood Po2 exiting the network fell from 66 mm Hg normally to 48 mm Hg during the severest anemia. Concurrently, the equilibrium tissue O2 tensions dropped from 44 to 23 mm Hg. For CO2 the exit blood Pco2 was 58 mm Hg for a 15% hematocrit, an increase of 4 mm Hg from the normal value, and equilibrium tissue Pco2 increased from 56 to 61 mm Hg. Blood flow increases from normal values necessary to offset the effects of the decreased O2 delivery to the tissue were 26, 86, and 222%, respectively, for hematocrits of 35, 25, and 15%. We compared our model results with recent experimental studies that have suggested that the amount of O2 diffusion is much higher than predicted values. We found that these experimental O2 gradients are three to four times larger than theoretical.

Dynamic Break-Up and Drop Formation From a Liquid Jet Spun From a Rotating Orifice: Part I — Experimental

2003 ◽  
Author(s):  
David Wong ◽  
Mark Simmons ◽  
Andrew King ◽  
Stephen Decent ◽  
Emilian Parau
Keyword(s):  
Dynamic Viscosity ◽  
Rotation Rate ◽  
Nonlinear Effects ◽  
Size Distributions ◽  
Strong Function ◽  
Highly Nonlinear ◽  
Experimental Parameters ◽  
Break Up ◽  
Drop Size Distributions ◽  
Viscous Solutions

The dynamics of the break-up of curved jets produced by the prilling process were studied. The effects of liquid dynamic viscosity, rotation rate and orifice size upon the surface tension driven instabilities were investigated. Liquid dynamic viscosity was varied by using mixtures of glycerol and water which gave dynamic viscosities ranging from 0.001 to 0.081 Pa.s at 20°C. Over the range of experimental parameters studied, four different break-up modes were identified. For each mode, considerable differences in the break-up mechanism and in the drop size distributions produced were observed. Dimensional analysis has shown that the break-up modes can be predicted from a plot of Reynolds number against Weber number. The break-up mode observed is a strong function of viscosity and highly nonlinear effects were observed with the most viscous solutions used. The effect of rotation rate on the jet break-up length was inconclusive from the experiment.

Study on the Extraction and Antioxidant Activity of Total Flavonoids from Netted Melon with Ultrasonic

2013 ◽  
Vol 807-809 ◽  
pp. 2003-2008
Author(s):  
Xi Yun Sun ◽  
Shu Yang ◽  
Chang Liu ◽  
Tian Lai Li ◽  
Ya Qi Duan
Keyword(s):  
Antioxidant Activity ◽  
Radical Scavenging ◽  
Extraction Yield ◽  
Oxygen Radical ◽  
Orthogonal Test ◽  
Total Flavonoids ◽  
Single Factor ◽  
Orthogonal Tests ◽  
Pyrogallol Autoxidation ◽  
Reducing Capacity

The single factor and orthogonal tests were designed to study the perfect conditions of extracting total flavononids from Netted Melon and the antioxidant activity of the extract. Firstly,the best conditions of extracting total flavononids from Netted Melon by single factor and orthogonal test was:ultrasonic power was 60%(250W) ,concentration of ethanol was 90%(V/V),extraction time was 60min ,volume of ethanol was 25mL.Under these conditions,the extraction yield of flavonoids was 0.2247 mg/g,which was 88.43% of the result of soxhlet,while,the time was 25% of soxhlet,from which the work efficiency was greatly improved. Then Prussian blue, Pyrogallol autoxidation, Phenanthroline and DPPH were used to research the antioxidant activity of flavonoid. It shows that flavonoid of Netted Melon can remove DPPH and hydroxyl radical strongly, also it has reducing capacity, but its ability of oxygen radical scavenging is poor.

Optimization for Purification Technology of Platycodins by Macroreticular Resin

2013 ◽  
Vol 781-784 ◽  
pp. 852-855
Author(s):  
Xue Yuan Jin ◽  
Hong Liu ◽  
San Fu Zhu
Keyword(s):  
Adsorption Capacity ◽  
Orthogonal Test ◽  
Single Factor ◽  
Macroporous Resin ◽  
Adsorption Time ◽  
Platycodon Grandiflorum ◽  
Adsorption Temperature ◽  
Adsorption Quantity

In order to purify the platycodins from Platycodon grandiflorum, AB-8 macroporous resin was used to test. Based on single factor experiments, orthogonal test was used to optimum the purification conditions. Adsorption pH, adsorption temperature, adsorption time and platycodins concentration were as factors and adsorption capacity was as index. The results were as follows: adsorption pH 6.0, adsorption temperature 40°C, adsorption tim110min, platycodins concentration 2.0mg/mL were the optimization conditions.The adsorption quantity reached at 39.1mg/g. So AB-8 macroporous resin was a suitable resin for purify the platycodins from Platycodon grandiflorum.

Preparation of Denatured Alcohol-Modified SPI-Based Adhesive

2012 ◽  
Vol 557-559 ◽  
pp. 987-990
Author(s):  
Yu Feng Ban ◽  
Hai Feng Zhu ◽  
Wei Zhao
Keyword(s):  
Shear Strength ◽  
Calcium Hydroxide ◽  
Soy Protein ◽  
Soy Protein Isolate ◽  
Protein Isolate ◽  
Orthogonal Test ◽  
Test Results ◽  
Single Factor ◽  
Air Drying ◽  
Environment Friendly

An environment-friendly soy protein isolate (SPI)-based adhesive for wood was prepared using denatured alcohol-modified SPI, calcium hydroxide and sodium silicate. On the basis of the single factor test results, an orthogonal test of 4 elements and 3 levels was carried out to optimize formula ingredients. The modified SPI adhesive contained more calcium hydroxide than unmodified SPI adhesive and exhibited good performance. The shear strength of the specimen bonded with the modified adhesive was 82.3 MPa; after three cycles of water-soaking and air-drying, the decrease in shear strength was as low as 7.9%.

scholarly journals Study on optimal adsorption conditions of norfloxacin in water based on response surface methodology

2022 ◽  
Author(s):  
Ming Zhang ◽  
Kuo Zhang ◽  
Jinpeng Wang ◽  
Runjuan Zhou ◽  
Jiyuan Li ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Reaction Temperature ◽  
Polynomial Regression ◽  
Single Factor ◽  
Solution Ph ◽  
Box Behnken Design ◽  
Simulated Wastewater ◽  
Predicted Values ◽  
Single Factor Experiment

Abstract The waste pomelo peel was pyrolyzed at 400 °C to prepare biochar and used as adsorbent to remove norfloxacin (NOR) from simulated wastewater. The adsorption conditions of norfloxacin by biochar were optimized by response surface methodology (RSM). On the basis of single-factor experiment, the adsorption conditions of biochar dosage, solution pH and reaction temperature were optimized by Box-Behnken Design (BBD), and the quadratic polynomial regression model of response value Y1 (NOR removal efficiency) and Y2 (NOR adsorption capacity) were obtained respectively. The results show that the two models are reasonable and reliable. The influence of single factor was as follows: solution pH > biochar dosage > reaction temperature. The interaction between biochar dosage and solution pH was very significant. The optimal adsorption conditions after optimization were as follows: biochar dosage = 0.5 g/L, solution pH = 3, and reaction temperature = 45 °C. The Y1 and Y2 obtained in the verification experiment were 75.68% and 3.0272 mg/g, respectively, which were only 2.38% and 0.0242 mg/g different from the theoretical predicted values of the model. Therefore, the theoretical model constructed by response surface methodology can be used to optimize the adsorption conditions of norfloxacin in water.

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