Microstructure Characteristics of YBa2Cu3O7-y Nanocomposite by Shortening the Manufacturing Process

2020 ◽  
Vol 20 (11) ◽  
pp. 6703-6705
Author(s):  
Sang Heon Lee
Keyword(s):  
Surface Area ◽  
Material Properties ◽  
Manufacturing Process ◽  
Boundary Surface ◽  
Important Goal ◽  
Ybco Bulk ◽  
Microstructure Characteristics ◽  
Large Particles

In this study, YBCO bulk was produced using two seeds by placing an additional seed on the upper pellet of the sample fabricated with the ISMG process. It was confirmed that the upper and lower pellets consisting of a–b sector showed a higher number of Y211 particles than those consisting of a–c sector, and that the same tendency appeared at a spot where different interfaces existed. This can be most clearly compared at the center. Finally, it was found that although minimizing the growth of a–c sector is an important goal for fabricating superconducting bulk magnets with high material properties, it is necessary to minimize the size of areas where different interfaces appear. It can be seen that the number of Y211 particles is the smallest inside the boundary surface, and that although they occupied a relatively smaller surface area, large particles agglomerated together.

Investigation of Non-specular Reflection of Rayleigh Waves for Evaluation of the Material Properties of Surface Area

2012 ◽  
Vol 62 (2) ◽  
pp. 179-184
Author(s):  
Hak-Joon KIM ◽  
Sung-Jin SONG ◽  
Joon-Ho CHOI ◽  
Sung-Duk KWON*
Keyword(s):  
Surface Area ◽  
Material Properties ◽  
Rayleigh Waves ◽  
Specular Reflection

EFFECT OF MUZZLING ON RUMINATION IN SHEEP

1988 ◽  
Vol 68 (2) ◽  
pp. 387-397 ◽  
Author(s):  
K. CHAI ◽  
L. P. MILLIGAN ◽  
G. W. MATHISON
Keyword(s):  
Key Words ◽  
Surface Area ◽  
Retention Time ◽  
Intestinal Tract ◽  
Rumen Fluid ◽  
Fluid Retention ◽  
Input Output ◽  
Reed Canarygrass ◽  
Large Particles ◽  
Microbial Attack

Two experiments were completed using four esophageal-fistulated sheep (two per experiment) to study the breakdown of rumen particles of grass hay (bromegrass or reed canarygrass) when rumination was either allowed to occur normally or was restricted by means of a muzzle. When the sheep were muzzled during the nonfeeding portion of the day, there was a distinct limitation of voluntary hay intake. Muzzled sheep chewed more often than unmuzzled sheep (P < 0.01) during eating and, presumably as a result, the particles in their mastication boluses were smaller (P < 0.05). During rumination the regurgitated and chewed boluses from sheep that had been muzzled were larger (P < 0.05) than those from unmuzzled sheep. The proportion of large particles (LP, particles retained on a 1.00-mm screen) of the regurgitated bolus, rumen contents and feces were greater (P > 0.05) for muzzled than unmuzzled sheep. The effectiveness of breakdown of LP retained for chewing during the rumination cycle increased (P < 0.005) with time after feeding (33% at 3 h postfeeding for bromegrass; 57% at 11 h postfeeding). This increase was eliminated by muzzling. The specific fragility (LP breakdown per chew per unit of LP in mouth) of particles from unmuzzled sheep was consistently greater (P > 0.05) than that of particles from muzzled animals. Muzzling markedly reduced the extent to which specific fragility increased with time after feeding and increased (P > 0.01) rumen fluid retention time from 7.4 to 17.4 h. The rumen input-output balance for hay particles was estimated. It is concluded that rumination is the major factor in decreasing the size of forage particles in the rumen, thereby exposing greater surface area to microbial attack and facilitating passage along the intestinal tract. Key words: Sheep, rumination, muzzle, particle breakdown, specific fragility, rumen retention time

scholarly journals On the Estimation of the Molecular Inaccessible Volume and the Molecular Accessible Surface of a Ligand in Protein Ligand Systems

2021 ◽  
Author(s):  
Konstantinos Konstantinidis ◽  
Ioannis Karakasiliοtis ◽  
Kostas Anagnostopoulos ◽  
Georgios Boulougouris
Keyword(s):  
Surface Area ◽  
Boundary Surface ◽  
Accessible Surface Area ◽  
Specific Protein ◽  
Solvent Accessible Surface Area ◽  
Protein Drug ◽  
Novel Approach ◽  
Candidate Protein ◽  
Accessible Surface ◽  
Solvent Accessible Surface

<p> In this work, a novel approach is proposed based on the accurate computation of a protein’s inaccessible volume as regards to a ligand, plus the corresponding surface area, where the ligand can be placed in order to “touch” the protein without any overlaps. The proposed approach can be thought as an extension of the widely used concept of the Solvent-Accessible Surface Area (SASA), evaluating the surface generated by the ligand while being rolled over all the atoms of the protein without penetrating them. Identification of the inaccessible volume of each candidate protein-ligand pair is also provided in the context of this study, along with the boundary surface where the ligand can be placed so as to be in “contact” with the protein, which is expected to significantly enhance the ability to investigate specific protein drug interactions.</p>

Experimental investigation of the curing behaviour of fibre composite structures with snap-cure polymer systems

2018 ◽  
Vol 9 (6) ◽  
pp. 768-778
Author(s):  
Rafal Stanik ◽  
Albert Langkamp ◽  
Michael Müller ◽  
Maik Gude ◽  
Anna Boczkowska
Keyword(s):  
Experimental Investigation ◽  
Temperature Field ◽  
Process Parameters ◽  
Material Properties ◽  
Manufacturing Process ◽  
Composite Structures ◽  
Fibre Composite ◽  
Uniform Design ◽  
Curing Process ◽  
Content Type

PurposeNovel snap-cure polymers (SCPs), as matrix systems for high-performance fibre composite materials, provide high potential for manufacturing of component families with small batch sizes and high variability. Especially, the processing of powdered SCP is associated with relatively simple and inexpensive tools. In addition, because of their curing behaviour, they allow short tooling times so that the production of small batch size components is possible in relatively short cycle times. To enable an efficient manufacturing process, an understanding of the curing process is necessary. An adjustment of the process parameters for a uniform design of the temperature field in the material during the manufacturing process is essential. The paper aims to discuss this issue.Design/methodology/approachFor this, a powder SCP resin system was investigated under process-specific conditions. An experimental test approach for determination of various thermal and kinetic material properties was developed. For the adjustment of the process parameters and monitoring of the curing state during the manufacturing process, a kinetic material model was determined. In the end, the validation of the determined model was performed. For this, the temperature distribution under process- specific conditions was measured in order to monitor the curing state of the material.FindingsThe experimental investigation showed an uneven temperature field in the material, which leads to an inhomogeneous curing process. This can lead to residual stresses in the structure, which have a critical impact on the material properties.Originality/valueThe determined kinetic model allows a prediction of the curing reaction and adjustment of the process parameters which is essential, especially for thick-walled components with SCPs.

Interface Bonding Property of Fiber-Reinforced Resin Mineral Composite

2012 ◽  
Vol 253-255 ◽  
pp. 499-502
Author(s):  
Xiu Hua Ren ◽  
Ze Ning Wang ◽  
Tao Wang ◽  
Jian Hua Zhang
Keyword(s):  
Finite Element ◽  
Mechanical Strength ◽  
Finite Element Simulation ◽  
Surface State ◽  
Material Properties ◽  
Resin Matrix ◽  
Interface Bonding ◽  
Microstructure Characteristics ◽  
Element Simulation ◽  
Bonding Property

Resin mineral composite (RMC) reinforced by fibers belongs to a multiphase material, whose mechanical strength depends on its material properties of components and microstructure characteristics of fibers including surface state, shape, and so on. The interface mechanism between fiber and matrix was analyzed. Finite element simulation was employed to discuss the reinforced effect of fiber on resin matrix, and the influence of fiber shape, surface state on interface bonding property respectively. Research results showed that linear fibers with surface dents or fibers shaped like S, U, V, N, W English letters performed well, and had much better reinforced effects on matrix than ordinary linear fibers.

scholarly journals Manufacturing Process beyond Conventional Plasticity Theory: Case Study in Manufacturing Low Spring Index Coil

2020 ◽  
Vol 1 (2) ◽  
pp. 98-104
Author(s):  
Yunan Prawoto ◽  
Sonia Manville ◽  
T Sakai ◽  
M Tanaka ◽  
T Gnauple-Herold
Keyword(s):  
Residual Stress ◽  
Fracture Mechanics ◽  
Material Properties ◽  
Manufacturing Process ◽  
Annealing Process ◽  
Plasticity Theory ◽  
Coil Spring ◽  
Academic World

In the academic world, conventional plasticity theory limits the cold process due to energy inefficiency, material properties and residual stress that may inhibit the quality of a product, and therefore usually not recommended. However, industrial competition pushes that limits against the edge. Knowing the consequences in advance helps reducing the damage that may have been caused by such a violation. This paper shows an example in the form of a case study. A coil spring with a very low spring index that academically suggested to be made using hot process was attempted to be manufactured using cold coiling machine. The case study shows that although it is possible, extra careful and timely handling must be done to successfully manufacture it. A coil with excessive residual stress is shown in this paper. That residual stress alone was capable in damaging the coil during manufacturing. The defect takes place after coiling and before tempering process. A fracture mechanics was used to analyze the failure, which is the splitting due to excessive residual stress. The case study also shows that the problem can be solved by speedy and subsequent stress relieve annealing process.

scholarly journals On the Estimation of the Molecular Inaccessible Volume and the Molecular Accessible Surface of a Ligand in Protein Ligand Systems

2021 ◽  
Author(s):  
Konstantinos Konstantinidis ◽  
Ioannis Karakasiliοtis ◽  
Kostas Anagnostopoulos ◽  
Georgios Boulougouris
Keyword(s):  
Surface Area ◽  
Boundary Surface ◽  
Accessible Surface Area ◽  
Specific Protein ◽  
Solvent Accessible Surface Area ◽  
Protein Drug ◽  
Novel Approach ◽  
Candidate Protein ◽  
Accessible Surface ◽  
Solvent Accessible Surface

<p> In this work, a novel approach is proposed based on the accurate computation of a protein’s inaccessible volume as regards to a ligand, plus the corresponding surface area, where the ligand can be placed in order to “touch” the protein without any overlaps. The proposed approach can be thought as an extension of the widely used concept of the Solvent-Accessible Surface Area (SASA), evaluating the surface generated by the ligand while being rolled over all the atoms of the protein without penetrating them. Identification of the inaccessible volume of each candidate protein-ligand pair is also provided in the context of this study, along with the boundary surface where the ligand can be placed so as to be in “contact” with the protein, which is expected to significantly enhance the ability to investigate specific protein drug interactions.</p>

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