Groove structure on the drainage characteristics of the gas curtain

The titanium-osteoblast-interaction can be influenced both by surface roughness and by chemical modifications. We have ascertained that a positively charged titanium surface boosts osteoblast cells adhesion due to their negatively charged cellular hyaluronan coat. In current experiments, chemical surface modifications were combined with different topographies. Titanium disks of technical purity were modified (i) in their roughness by polishing (P), machining (M) and corundum blasting (CB), and (ii) by subsequently chemical functionalization by a thin film (d≤0.1 µm) of microwave plasma polymerized allylamine (PPAAm). In addition, collagen I was immobilized on PPAAm via the bifunctional linker polyethylene glycol diacid or glutar dialdehyde, respectively. The cell shape and material's contact of human osteoblasts was analyzed by FE-SEM and time dependent cell adhesion measured by flow cytometry. The cell dynamic of the adhesion component vinculin was observed in living cells. Amino-functionalization (PPAAm) considerably enhances the adhesion of osteoblasts in combination with topographical features, which was in contrast to collagen modified surfaces. PPAAm allows the cells to literally melt into the groove structure of the titanium. The bone cells lie over a large area and very close to the surface, so that the edges of the cells can hardly be distinguished from the structure of the surface. The combinatory effect of topography and plasma modification could improve bonding of the implant to the bone tissue.

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A Study of Drag Reduction on Cylinders with Different V-Groove Depths on the Surface

Water ◽

10.3390/w14010036 ◽

2021 ◽

Vol 14 (1) ◽

pp. 36

Author(s):

Jiyang Qi ◽

Yue Qi ◽

Qunyan Chen ◽

Fei Yan

Keyword(s):

Drag Reduction ◽

Drag Coefficient ◽

Vortex Structure ◽

Lift Coefficient ◽

Pressure Coefficient ◽

Reynolds Numbers ◽

Groove Surface ◽

Smooth Cylinder ◽

Groove Structure ◽

Reduction Effect

In this study, the drag reduction effect is studied for a cylinder with different V-groove depths on its surface using a k-ω/SST (Shear Stress Transport) turbulence model of computational fluid dynamics (CFD), while a particle image velocimetry (PIV) system is employed to analyze the wake characteristics for a smooth cylinder and a cylinder with different V-groove depths on its surface at different Reynolds numbers. The study focuses on the characteristics of the different V-groove depths on lift coefficient, drag coefficient, the velocity distribution of flow field, pressure coefficient, vortex shedding, and vortex structure. In comparison with a smooth cylinder, the lift coefficient and drag coefficient can be reduced for a cylinder with different V-groove depths on its surface, and the maximum reduction rates of lift coefficient and drag coefficient are about 34.4% and 16%, respectively. Otherwise, the vortex structure presents a complete symmetry for the smooth cylinder, however, the symmetry of the vortex structure becomes insignificant for the V-shaped groove structure with different depths. This is also an important reason for the drag reduction effect of a cylinder with a V-groove surface.

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Beam control of high-power broad-area photonic crystal lasers using ladderlike groove structure

Applied Physics Express ◽

10.7567/apex.10.062701 ◽

2017 ◽

Vol 10 (6) ◽

pp. 062701

Author(s):

Tao Wang ◽

Lijie Wang ◽

Shili Shu ◽

Sicong Tian ◽

Zefeng Lu ◽

...

Keyword(s):

Photonic Crystal ◽

High Power ◽

Broad Area ◽

Beam Control ◽

Groove Structure

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An Optimum Design of Replication Process to Improve Birefringence, Radial-Tilt and Land-Groove Structure in DVD-RAM Substrates

Transactions of the Korean Society of Mechanical Engineers A ◽

10.3795/ksme-a.2002.26.4.637 ◽

2002 ◽

Vol 26 (4) ◽

pp. 637-643

Author(s):

Sin-Il Gang ◽

Gi-Byeong Seong ◽

Nam-Seok Lee

Keyword(s):

Optimum Design ◽

Replication Process ◽

Groove Structure

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Optimization of Herbicide Use: Study on Spreading and Evaporation Characteristics of Glyphosate-Organic Silicone Mixture Droplets on Weed Leaves

Agronomy ◽

10.3390/agronomy9090547 ◽

2019 ◽

Vol 9 (9) ◽

pp. 547 ◽

Cited By ~ 3

Author(s):

Li ◽

Travlos ◽

Qi ◽

Kanatas ◽

Wang

Keyword(s):

Leaf Surface ◽

Orthogonal Experiment ◽

Digital Camera ◽

Weed Species ◽

Coverage Area ◽

Binary Images ◽

Spread Area ◽

Droplet Sizes ◽

Groove Structure ◽

Herbicide Use

Herbicide deposition rate can be affected by the leaf surface features of weeds and have a significant impact on the overall efficacy. In this paper, an orthogonal experiment was conducted to investigate the differences of droplet evaporation and spreading characteristics corresponding to weed leaf surface with hairy, waxy and rough (ridged) structures. Three weed species—Descurainia sophia, Lepidium lotifolium, and Lolium temulentum—were included in the study, representing these three leaf structures respectively. Glyphosate sprays with organic silicone surfactant in different concentrations were composed for the test. Single droplets with two diameters of 0.05 μL and 0.1 μL were deposited on the leaves to evaluate the evaporation and spreading characteristics. A digital camera was used and the evaporation duration and the maximum droplet coverage images could be captured and extracted from the recorded videos. The Image Processing Toolbox in Matlab was applied to segment the images for droplet and leaf background and the binary images’ pixel numbers were counted for coverage area calculation. The results revealed that the evaporation duration was reduced with the increase of the organic silicone concentration, while the spread area was expanded. The droplet spread more widely and evaporated faster on D. sophia leaves than on the leaves with L. lotifolium and L. temulentum surfaces. The spreading area and evaporation duration varied much faster on L. lotifolium leaves than on the leaves of other weed species. The droplet sizes affected spreading more significantly on L. temulentum leaf surface, as the spreading procedure of small size droplets was restrained by the groove structure. The results of this study would benefit the consideration of the farmers when selecting the proper nozzle code and the determining of the surfactant mixture in order to optimize the use of herbicides like glyphosate.

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Simulation of liquid transfer between the plate and the groove

Modern Physics Letters B ◽

10.1142/s0217984920503315 ◽

2020 ◽

Vol 34 (30) ◽

pp. 2050331

Author(s):

Nan Zhou ◽

Jiayi Zhao ◽

Shuo Chen ◽

Yang Liu ◽

Kaixuan Zhang

Keyword(s):

Transfer Rate ◽

Dissipative Particle Dynamics ◽

Surface Wettability ◽

Breakup Process ◽

Many Body ◽

The Core ◽

Groove Structure ◽

Liquid Transfer ◽

Core Problem ◽

Dynamics Method

The transfer of the liquid from groove to plate is significantly affected by the breakup process of liquid bridge, which is the core problem of gravure. In this paper, many-body dissipative particle dynamics method (MDPD) is used to simulate the behaviors of the stretching liquid cylinder between the plate and the groove, and the influence of surface wettability, stretching velocity and groove structure on the liquid cylinder rupture and the transfer rate of liquid are studied. The results show that both of the slipping velocity of the contact line on the plate and the thinning velocity of the liquid cylinder determine the breakup state of the liquid bridges and the liquid transfer rate from the groove to the plate. In the cases with the same surface wettability, at high hydrophilicity surface, the transfer rate increases firstly and then decreases with the increase of the stretching velocity. In the cases with different surface wettability of the plate and the groove, reducing the stretching velocity and the inclination angle of the groove are helpful to pull the liquid out of the groove and increase the transfer rate, and it could also be achieved by increasing the wettability of the plate and decreasing the wettability of the groove. This study provides some new insights into the effects of surface wettability, stretching velocity and groove structure on the dynamics of breakup process and liquid transfer in stretching.

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Thickness analysis of complex two-step micro-groove on plate during rubber pad forming process

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406220933922 ◽

2020 ◽

pp. 095440622093392

Author(s):

Fei Teng ◽

Hongyu Wang ◽

Juncai Sun ◽

Xiangwei Kong ◽

Jie Sun ◽

...

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Thickness Variation ◽

Forming Process ◽

Rubber Pad Forming ◽

Groove Structure ◽

Thickness Variations ◽

Accuracy Of Results ◽

Plane Slab ◽

Element Method

The surface groove structure has numerous functions based on their shapes. In order to make these functions developed, both new shapes and processing forms of the surface structures are being innovated. In this paper, not only the advanced rubber pad forming process is used, but also a new kind of micro-groove with two-step structures is designed. A model based on multi-plane slab method is proposed to analyze the process. According to the stress acting condition, a half of two-step micro-groove structure is divided into seven areas in the width direction. The thickness variation of plate in each area is obtained. When the shape, depth, width, and height ratio of the first and second-step micro-groove are different, the thickness variations of the plate are analyzed. In order to verify the accuracy of the model, both finite element method and pressing experiment are done. Based on the results provided by both finite element method and experiment, the accuracy of results calculated by analytical model is verified.

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