Fabrication and characterization of open cell porous regular interconnected metallic structure with solid core

2016 ◽  
Vol 232 (2) ◽  
pp. 305-316 ◽  
Author(s):  
Jatender Pal Singh ◽  
Pulak M Pandey
Keyword(s):  
Metal Powder ◽  
Inner Core ◽  
Ceramic Powder ◽  
Three Dimensional ◽  
Cost Effective ◽  
Solid Core ◽  
Metallic Structure ◽  
Open Cell ◽  
Cost Effective Technique ◽  
Metallic Parts

Metallic parts having open cell porous regular interconnected metallic structure of predetermined unit cell are being fabricated using metal powder–based rapid prototyping machines. These machines are capital intensive. All porous structures including open cell porous regular interconnected metallic structure have less density, so they lack in strength problems as compared to the solid structure. The strength of open cell porous regular interconnected metallic structure can be enhanced by providing solid inner core. In this study, a cost-effective technique has been developed to fabricate open cell porous regular interconnected metallic structure with solid core using ceramic powder–based three-dimensional printing machine and pressureless sintering. In this work, two approaches of fabrication were developed. In the first approach, only spherical metal powder was used, while in the second approach, a solid metallic rod along with spherical metal powder was utilized. Interconnected porosity and sinter density of the fabricated specimens were measured using Archimedes’ principle. The characterization was done using microstructure analysis, energy dispersive analysis, scanning electron microscopy and X-ray diffraction analysis. Mechanical properties of developed structures were determined using tensile, compressive and impact tests.

Fabrication and assessment of mechanical properties of open cell porous regular interconnected metallic structure through rapid manufacturing route

2018 ◽  
Vol 24 (1) ◽  
pp. 138-149 ◽  
Author(s):  
Jatender Pal Singh ◽  
Pulak Mohan Pandey
Keyword(s):  
Mechanical Properties ◽  
Computer Aided Design ◽  
Ceramic Powder ◽  
Pressureless Sintering ◽  
Sintering Process ◽  
Metallic Structure ◽  
Porosity Level ◽  
Open Cell ◽  
Content Type ◽  
Interconnected Porosity

Purpose The requirements of open cell porous regular interconnected metallic structure (OCPRIMS) in applications such as heat exchangers, sound absorption, fluid flow control, spark arresters and biocompatible inserts have been increased. As per available technology in the present scenario, only the metallic-based rapid prototyping (RP) machines can guarantee fabrication of OCPRIMS. Metal-based RP machines are capital-intensive. So, this study aims to develop a technique for fabrication of OCPRIMS economically using three-dimensional printing (3 DP) and pressureless sintering. Design/methodology/approach Three computer-aided design (CAD) models of varying designed interconnected porosity 73, 70 and 60 per cent were modeled to target metallic porosity 27, 30 and 40 per cent. The same were fabricated with ceramic-based powder using 3 DP. Thereafter, spherical bronze powder with average size of 200 µm was filled and sintered in pressureless manner under inert atmosphere of argon. After sintering, the specimens were cleaned with the help of pricking needles and high-pressure water. It flushed the burnt ceramic powder and allowed metallic portion to remain intact. The obtained specimens were inverse of CAD/3 DP models. The dimensional measurement at different stages of fabrication was carried out to find shrinkage. Sintered density and interconnected porosity were measured using Archimedes’ principle. The characterization of the fabricated specimens was done with the help of microstructure analysis, scanning electron microscopy and energy dispersive x-ray analysis. Mechanical properties were assessed using compressive, tensile and Charpy tests. Findings The feasibility has been explored successfully to fabricate OCPRIMS of phosphor bronze using 3 DP and pressureless sintering process. Interconnected porosity of 51.45, 56.45, 64.09 per cent of final metallic specimens has been observed against the targeted 27, 30 and 40 per cent. The increase in pore dimensions up to 19.13 per cent and shrinkage up to 5.44 per cent of outer dimensions were found to be the main causes of increase in interconnected porosity level. The characterization results exhibit the behavior of pressureless sintering process and stability of the fabricated specimens. Mechanical properties of fabricated structures are found to be dependent on porosity and strut diameter. Compressive and tensile strength decrease with the increase in porosity for strut diameter less than 1 mm, whereas they increase with the increase in strut diameter of 1 mm or more. A similar trend has been observed for impact strength also. Originality/value This paper explores the feasibility to fabricate OCPRIMS economically using 3 DP and pressureless sintering process.

scholarly journals Three-dimensional ultrasound scanning

2011 ◽  
Vol 1 (4) ◽  
pp. 503-519 ◽  
Author(s):  
Aaron Fenster ◽  
Grace Parraga ◽  
Jeff Bax
Keyword(s):  
Carotid Atherosclerosis ◽  
Imaging Techniques ◽  
Three Dimensional ◽  
Cost Effective ◽  
Imaging Systems ◽  
Two Dimensional ◽  
Effective Technique ◽  
The Past ◽  
Cost Effective Technique ◽  
Three Dimensional Images

The past two decades have witnessed developments of new imaging techniques that provide three-dimensional images about the interior of the human body in a manner never before available. Ultrasound (US) imaging is an important cost-effective technique used routinely in the management of a number of diseases. However, two-dimensional viewing of three-dimensional anatomy, using conventional two-dimensional US, limits our ability to quantify and visualize the anatomy and guide therapy, because multiple two-dimensional images must be integrated mentally. This practice is inefficient, and may lead to variability and incorrect diagnoses. Investigators and companies have addressed these limitations by developing three-dimensional US techniques. Thus, in this paper, we review the various techniques that are in current use in three-dimensional US imaging systems, with a particular emphasis placed on the geometric accuracy of the generation of three-dimensional images. The principles involved in three-dimensional US imaging are then illustrated with a diagnostic and an interventional application: (i) three-dimensional carotid US imaging for quantification and monitoring of carotid atherosclerosis and (ii) three-dimensional US-guided prostate biopsy.

Inspection and Grading of Surface Defects of Fruits by Computer Vision

2011 ◽  
Vol 317-319 ◽  
pp. 956-961 ◽  
Author(s):  
Jiang Bo Li ◽  
Xiu Qin Rao ◽  
Yi Bin Ying
Keyword(s):  
Computer Vision ◽  
Multispectral Imaging ◽  
Surface Defects ◽  
Three Dimensional ◽  
Cost Effective ◽  
Agricultural Industry ◽  
Advantages And Disadvantages ◽  
Pattern Recognition Methods ◽  
Cost Effective Technique ◽  
3D Information

Computer vision is a rapid, consistent and objective inspection technique, which has expanded into many diverse industries. Its speed and accuracy provide one alternative for an automated, non-destructive and cost-effective technique to accomplish ever-increasing production and quality requirements. This method of inspection has found applications in the agricultural industry, including the inspection and grading of fruits. This paper provides an introduction to main defection and grading approaches of fruit external defects, including image processing and pattern recognition methods based on fruit two-dimensional (2D) and three-dimensional (3D) information, and hyperspectral and multispectral imaging. In addition, their advantages and disadvantages are also discussed.

Experimental Investigations for Fabrication and Comparison of Fatigue Properties of an Open Cell Porous Regular Metallic Structure and with Inner Solid Core through Rapid Manufacturing

2016 ◽  
Vol 1137 ◽  
pp. 52-60
Author(s):  
Jatender Pal Singh ◽  
Pulak M. Pandey
Keyword(s):  
Fatigue Testing ◽  
Fatigue Properties ◽  
Experimental Investigations ◽  
Rapid Manufacturing ◽  
Solid Core ◽  
Metallic Structure ◽  
Open Cell ◽  
Initiation And Propagation ◽  
As Stress ◽  
Shrinkage Cavities

In this study parts having Open Cell Porous Regular Interconnected Metallic Structure (OCPRIMS) of cubic unit cell and OCPRIMS with inner solid core were fabricated through developed process of Rapid Manufacturing (RM) process. Two approaches were used to fabricate inner solid core i,e one by using metallic phosphor bronze powder and other by using solid phosphor bronze rod. The specimens were fabricated in accordance with ISO 3928: 1999 and subjected to tension-tension and compressive-compressive fatigue testing. The endurance limit of OCPRIMS with solid rod cored structure was found to be on the higher side in comparison to other types of specimens. The results of Scanning Electron Microscopy (SEM) and images of fractured surfaces showed the presence of voids, shrinkage cavities and pointed edges on the designed pores. They acted as stress raisers and facilitated crack initiation and propagation in the specimens.

A Chemical Perspective to the Anti-Amyloid Action of Compounds and a Nanoparticle Based Assay for Screening Amyloid Inhibitors

2020 ◽  
Author(s):  
Nidhi Gour ◽  
Bharti Koshti
Keyword(s):  
Memory Loss ◽  
Cost Effective ◽  
Structural Motif ◽  
Rapid Screening ◽  
Stacking Interactions ◽  
Aromatic Rings ◽  
Amyloid Fibers ◽  
Aromatic Stacking ◽  
Cost Effective Technique ◽  
The Brain

Aggregation of amyloid beeta 1-42 (Aβ<sub>42</sub>) peptide causes the formation of clustered deposits knows as amyloid plaques in the brain which leads to neuronal dysfunction and memory loss and associated with many neurological disorders including Alzheimer’s and Parkinson’s. Aβ<sub>42</sub> has core structural motif with phenylalanine at the 19 and 20 positions. The diphenylalanine (FF) residue plays a crucial role in the formation of amyloid fibers and serves as model peptide for studying Aβ<sub>42 </sub>aggregation. FF self-assembles to well-ordered tubular morphology via aromatic pi-pi stackings. Our studies, suggest that the aromatic rings present in the anti-amyloidogenic compounds may interact with the pi-pi stacking interactions present in the FF. Even the compounds which do not have aromatic rings, like cyclodextrin and cucurbituril show anti-amyloid property due to the binding of aromatic ring inside the guest cavity. Hence, our studies also suggest that compounds which may have a functional moiety capable of interacting with the aromatic stacking interactions might be tested for their anti-amyloidogenic properties. Further, in this manuscript, we have proposed two novel nanoparticle based assays for the rapid screening of amyloid inhibitors. In the first assay, interaction between biotin-tagged FF peptide and the streptavidin labelled gold nanoparticles (s-AuNPs) were used. In another assay, thiol-Au interactions were used to develop an assay for detection of amyloid inhibitors. It is envisaged that the proposed analytical method will provide a simple, facile and cost effective technique for the screening of amyloid inhibitors and may be of immense practical implications to find the therapeutic remedies for the diseases associated with the protein aggregation.

scholarly journals Conversion of sequence-characterized amplified region (SCAR) bands into high-throughput DNA markers based on RAPD technique for detection of the stem nematode Ditylenchus dipsaci in crucial plant hosts

2008 ◽  
Vol 53 (No. 3) ◽  
pp. 97-104 ◽  
Author(s):  
M. Zouhar ◽  
M. Marek ◽  
O. Douda ◽  
J. Mazáková ◽  
P. Ryšánek
Keyword(s):  
Cost Effective ◽  
Healthy Plant ◽  
Host Preferences ◽  
Sequence Characterized Amplified Region ◽  
Detection And Identification ◽  
Plant Hosts ◽  
Cost Effective Technique ◽  
Ditylenchus Dipsaci ◽  
Species Specific ◽  
Template Dna

<i>Ditylenchus dipsaci</i>, the stem nematode, is a migratory endoparasite of over 500 species of angiosperms. The main method of <i>D. dipsaci</i> control is crop rotation, but the presence of morphologically indistinguishable host races with different host preferences makes rotation generally ineffective. Therefore, a sensitive, rapid, reliable, as well as cost effective technique is needed for identification of <i>D. dipsaci</i> in biological samples. This study describes the development of species-specific pairs of PCR oligonucleotides for detection and identification of the <i>D. dipsaci</i> stem nematode in various plant hosts. Designed DIT-2 primer pair specifically amplified a fragment of 325 bp, while DIT-5 primer pair always produced a fragment of 245 bp in all <i>D. dipsaci</i> isolates. Two developed SCAR primer pairs were further tested using template DNA extracted from a collection of twelve healthy plant hosts; no amplification was however observed. The developed PCR protocol has proved to be quite sensitive and able to specifically detect <i>D. dipsaci</i> in artificially infested plant tissues.

Bucket handle meniscus tears in low-resource settings can be successfully treated with a cost-effective technique

2021 ◽  
Author(s):  
Allicia Ostoposides Imada ◽  
James J. O’Hara ◽  
Ignacio L. Proumen ◽  
Pablo S. Molinari ◽  
Daniel C. Wascher ◽  
...  
Keyword(s):  
Cost Effective ◽  
Effective Technique ◽  
Low Resource Settings ◽  
Low Resource ◽  
Meniscus Tears ◽  
Cost Effective Technique ◽  
Bucket Handle

scholarly journals Cyber-Physical Systems Improving Building Energy Management: Digital Twin and Artificial Intelligence

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2338
Author(s):  
Sofia Agostinelli ◽  
Fabrizio Cumo ◽  
Giambattista Guidi ◽  
Claudio Tomazzoli
Keyword(s):  
Artificial Intelligence ◽  
Renewable Energy ◽  
Energy Management ◽  
Three Dimensional ◽  
Cost Effective ◽  
Automation System ◽  
Climate Conditions ◽  
Digital Twin ◽  
Building Energy Management ◽  
Computing Paradigm

The research explores the potential of digital-twin-based methods and approaches aimed at achieving an intelligent optimization and automation system for energy management of a residential district through the use of three-dimensional data model integrated with Internet of Things, artificial intelligence and machine learning. The case study is focused on Rinascimento III in Rome, an area consisting of 16 eight-floor buildings with 216 apartment units powered by 70% of self-renewable energy. The combined use of integrated dynamic analysis algorithms has allowed the evaluation of different scenarios of energy efficiency intervention aimed at achieving a virtuous energy management of the complex, keeping the actual internal comfort and climate conditions. Meanwhile, the objective is also to plan and deploy a cost-effective IT (information technology) infrastructure able to provide reliable data using edge-computing paradigm. Therefore, the developed methodology led to the evaluation of the effectiveness and efficiency of integrative systems for renewable energy production from solar energy necessary to raise the threshold of self-produced energy, meeting the nZEB (near zero energy buildings) requirements.

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