Patterns design of filament wound spherical structure based on a new winding strategy

In order to satisfy the collision-resistance requirements for the stiffness and strength of collision-protected spherical structure of marine structure platforms, a new winding strategy for spherical structure was proposed, which can make the thickness distribution of the filament wound layer of the spherical structure relatively even, and the polar opening can be covered by the filament wound layer. In this paper, the filament wound trajectory equation and the approaches for winding parameters design of spherical structures were presented. The influence of different partitions on the thickness distribution of the filament wound layer for spherical structure was analyzed. The optimal partition was adjusted according to the even distribution condition of the filament wound patterns, and the simulation of the new winding strategy of the spherical structure, dry yarn filament wound experiment and the wet filament wound experiment was carried out with adjusted partitions. The results show that when adopting the new winding strategy, the obtained winding pattern is stable. The feasibility of the new winding strategy is verified, which can consequently improve the structural bearing capability of spherical structure.

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Design a New Spherical Super Element to Static and Modal Analysis of Spherical Structures

Volume 1: 23rd Biennial Conference on Mechanical Vibration and Noise, Parts A and B ◽

10.1115/detc2011-47151 ◽

2011 ◽

Author(s):

Hamid Faghani ◽

M. T. Ahmadian

Keyword(s):

Finite Element ◽

Modal Analysis ◽

Natural Frequencies ◽

Accurate Result ◽

Three Dimensional ◽

Hollow Structure ◽

Pressure Vessels ◽

Spherical Structure ◽

Spherical Structures ◽

Spherical Pressure

Hollow Spherical Structures such as spherical pressure vessels are widely used in industries. Using faster numerical methods to solve these spherical problems has been one of the research interests in the last decade. Super elements are elements capable of producing the same accurate result in comparison with several conventional elements. In this paper, a new spherical super element is designed and implemented to study the static deformation and modal analysis of a spherical structure. In the static analysis mean of the inner radial displacements of the hollow structure under the internal pressure is evaluated, also performing the modal analysis, natural frequencies of the structure under the specified boundary condition are obtained. Findings are compared with those of conventional finite element methods and very good agreements are achieved. Using two spherical super element result the same displacement in conventional finite element with 2164 three dimensional brick elements.

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Video real-time imaging of artificial membranes during freeze-drying by cryo-electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010010216x ◽

1988 ◽

Vol 46 ◽

pp. 16-17

Author(s):

Alan S. Rudolph ◽

Ronald R. Price

Keyword(s):

Real Time ◽

Self Assembly ◽

Freeze Drying ◽

Video Capture ◽

Drying Process ◽

Artificial Membranes ◽

The Past ◽

Cryo Electron Microscopy ◽

Spherical Structures ◽

Capture Techniques

We have employed cryoelectron microscopy to visualize events that occur during the freeze-drying of artificial membranes by employing real time video capture techniques. Artificial membranes or liposomes which are spherical structures within internal aqueous space are stabilized by water which provides the driving force for spontaneous self-assembly of these structures. Previous assays of damage to these structures which are induced by freeze drying reveal that the two principal deleterious events that occur are 1) fusion of liposomes and 2) leakage of contents trapped within the liposome [1]. In the past the only way to access these events was to examine the liposomes following the dehydration event. This technique allows the event to be monitored in real time as the liposomes destabilize and as water is sublimed at cryo temperatures in the vacuum of the microscope. The method by which liposomes are compromised by freeze-drying are largely unknown. This technique has shown that cryo-protectants such as glycerol and carbohydrates are able to maintain liposomal structure throughout the drying process.

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Photographic Equidensitometry of High Voltage Electron Images of Thick Noncrystalline Materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096229 ◽

1972 ◽

Vol 30 ◽

pp. 594-595

Author(s):

Keinosuke Kobayashi

Keyword(s):

High Voltage ◽

Linear Response ◽

Thickness Distribution ◽

Contour Map ◽

Mass Thickness ◽

Voltage Electron ◽

High Voltage Electron ◽

Homogeneous Particle ◽

Photographic Emulsions ◽

Logarithmic Relation

Equidensitometry as developed by E. Lau and W. Krug has been little used in the analysis of ordinary electron photomicrographs, yet its application to the high voltage electron images proves merits of this procedure. Proper sets (families) of equidensities as shown in the next page are able to reveal the contour map of mass thickness distribution in thick noncrystalline specimens. The change in density of the electron micrograph is directly related to the mass thickness of corresponding area in the specimen, because of the linear response of photographic emulsions to electrons and the logarithmic relation between electron opacity and mass thickness of amorphous object.This linearity is verified by equidensitometry of a spherical solid object as shown in Fig. 1a. The object is a large (1 μ) homogeneous particle of polystyrene. Fig. 1b is a composite print of three equidensities of the 1st order prepared from Fig. 1a.

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Electron-diffraction studies of amorphous carbon thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100151337 ◽

1993 ◽

Vol 51 ◽

pp. 1100-1101

Author(s):

David A. Muller

Keyword(s):

Thin Films ◽

Electron Diffraction ◽

Amorphous Carbon ◽

Glassy Carbon ◽

Spherical Structure ◽

Local Ordering ◽

Carbon Arc ◽

Similar Appearance ◽

Carbon Thin Films ◽

Large Spherical

The sp2 rich amorphous carbons have a wide variety of microstructures ranging from flat sheetlike structures such as glassy carbon to highly curved materials having similar local ordering to the fullerenes. These differences are most apparent in the region of the graphite (0002) reflection of the energy filtered diffracted intensity obtained from these materials (Fig. 1). All these materials consist mainly of threefold coordinated atoms. This accounts for their similar appearance above 0.8 Å-1. The fullerene curves (b,c) show a string of peaks at distance scales corresponding to the packing of the large spherical and oblate molecules. The beam damaged C60 (c) shows an evolution to the sp2 amorphous carbons as the spherical structure is destroyed although the (220) reflection in fee fcc at 0.2 Å-1 does not disappear completely. This 0.2 Å-1 peak is present in the 1960 data of Kakinoki et. al. who grew films in a carbon arc under conditions similar to those needed to form fullerene rich soots.

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Aerodynamic Shape Influence and Optimum Thickness Distribution Analysis of Perceptive Wind Turbine Blade

International Journal of Emerging Research in Management and Technology ◽

10.23956/ijermt.v7i3.6 ◽

2018 ◽

Vol 7 (3) ◽

pp. 1

Author(s):

J. V. Muruga Lal Jeyan ◽

Akhila Rupesh ◽

Jency Lal

Keyword(s):

Wind Energy ◽

Wind Turbine ◽

Thickness Distribution ◽

Turbine Blades ◽

Reduced Form ◽

Load Factor ◽

Strong Impact ◽

Theory Approach ◽

Distribution Analysis ◽

Optimum Thickness

The aerodynamic module combines the three-dimensional nonlinear lifting surface theory approach, which provides the effective propagated incident velocity and angle of attack at the blade section separately, and a two-dimensional panel method for steady axisymmetric and non-symmetric flow has to be involved to obtain the 3D pressure and velocity distribution on the wind mill model blade. Wind mill and turbines have become an economically competitive form of efficiency and renewable work generation. In the abroad analytical studies, the wind turbine blades to be the target of technological improvements by the use of highly possible systematic , aerodynamic and design, material analysis, fabrication and testing. Wind energy is a peculiar form of reduced form of density source of power. To make wind power feasible, it is important to optimize the efficiency of converting wind energy into productivity source. Among the different aspects involved, rotor aerodynamics is a key determinant for achieving this goal. There is a tradeoff between thin airfoil and structural efficiency. Both of which have a strong impact on the cost of work generated. Hence the design and analysis process for optimum design requires determining the load factor, pressure and velocity impact and optimum thickness distribution by finding the effect of blade shape by varying thickness on the basis of both the aerodynamic output and the structural weight.

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Combining SAR interferometry and the equation of continuity to estimate the three-dimensional glacier surface-velocity vector

Journal of Glaciology ◽

10.3189/s0022143000001398 ◽

1999 ◽

Vol 45 (151) ◽

pp. 533-538 ◽

Cited By ~ 2

Author(s):

Niels Reeh ◽

Søren Nørvang Madsen ◽

Johan Jakob Mohr

Keyword(s):

Steady State ◽

Mass Balance ◽

Vertical Velocity ◽

Velocity Vector ◽

Thickness Distribution ◽

Vertical Surface ◽

Horizontal Velocity ◽

Sar Interferometry ◽

Surface Velocity ◽

Ice Thickness

AbstractUntil now, an assumption of surface-parallel glacier flow has been used to express the vertical velocity component in terms of the horizontal velocity vector, permitting all three velocity components to be determined from synthetic aperture radar interferometry. We discuss this assumption, which neglects the influence of the local mass balance and a possible contribution to the vertical velocity arising if the glacier is not in steady state. We find that the mass-balance contribution to the vertical surface velocity is not always negligible as compared to the surface-slope contribution. Moreover, the vertical velocity contribution arising if the ice sheet is not in steady state can be significant. We apply the principle of mass conservation to derive an equation relating the vertical surface velocity to the horizontal velocity vector. This equation, valid for both steady-state and non-steady-state conditions, depends on the ice-thickness distribution. Replacing the surface-parallel-flow assumption with a correct relationship between the surface velocity components requires knowledge of additional quantities such as surface mass balance or ice thickness.

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Nanoemulsions Loaded with Amphotericin B: Development, Characterization and Leishmanicidal Activity

Current Pharmaceutical Design ◽

10.2174/1381612825666190705202030 ◽

2019 ◽

Vol 25 (14) ◽

pp. 1616-1622 ◽

Cited By ~ 1

Author(s):

Gabriela Muniz Félix Araújo ◽

Alana Rafaela Albuquerque Barros ◽

João Augusto Oshiro-Junior ◽

...

Keyword(s):

Amphotericin B ◽

Average Diameter ◽

Isopropyl Myristate ◽

Neglected Diseases ◽

Clinical Form ◽

Hydrophobic Compounds ◽

Internal Phase ◽

Oil In Water ◽

Spherical Structures ◽

Lipid Formulations

Leishmaniasis is one of the most neglected diseases in the world. Its most severe clinical form, called visceral, if left untreated, can be fatal. Conventional therapy is based on the use of pentavalent antimonials and includes amphotericin B (AmB) as a second-choice drug. The micellar formulation of AmB, although effective, is associated with acute and chronic toxicity. Commercially-available lipid formulations emerged to overcome such drawbacks, but their high cost limits their widespread use. Drug delivery systems such as nanoemulsions (NE) have proven ability to solubilize hydrophobic compounds, improve absorption and bioavailability, increase efficacy and reduce toxicity of encapsulated drugs. NE become even more attractive because they are inexpensive and easy to prepare. The aim of this work was to incorporate AmB in NE prepared by sonicating a mixture of surfactants, Kolliphor® HS15 (KHS15) and Brij® 52, and an oil, isopropyl myristate. NE exhibited neutral pH, conductivity values consistent with oil in water systems, spherical structures with negative Zeta potential value, monomodal size distribution and average diameter of drug-containing droplets ranging from 33 to 132 nm. AmB did not modify the thermal behavior of the system, likely due to its dispersion in the internal phase. Statistically similar antileishmanial activity of AmB-loaded NE to that of AmB micellar formulation suggests further exploring them in terms of toxicity and effectiveness against amastigotes, with the aim of offering an alternative to treat visceral leishmaniasis.

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