Mechanical Properties of Protective Coatings against Marine Fouling: A Review

The accumulation of marine organisms on ship hulls, such as microorganisms, barnacles, and seaweeds, represents a global problem for maritime industries, with both economic and environmental costs. The use of biocide-containing paints poses a serious threat to marine ecosystems, affecting both target and non-target organisms driving science and technology towards non-biocidal solutions based on physico-chemical and materials properties of coatings. The review reports recent development of hydrophobic protective coatings in terms of mechanical properties, correlated with the wet ability features. The attention is focused mainly on coatings based on siloxane and epoxy resin due to the wide application fields of such systems in the marine industry. Polyurethane and other systems have been considered as well. These coatings for anti-fouling applications needs to be both long-term mechanically stable, perfectly adherent with the metallic/composite substrate, and capable to detach/destroy the fouling organism. Prospects should focus on developing even “greener” antifouling coatings solutions. These coatings should also be readily addressable to industrial scale-up for large-scale product distribution, possibly at a reasonable cost.

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STRUCTURE AND PROPERTIES OF MULTI COMPONENT (Ti-Zr-Cr-Nb)N COATINGS OBTAINED BY VACUUM-ARC DEPOSITION

Tribologia ◽

10.5604/01.3001.0010.6946 ◽

2016 ◽

Vol 270 (6) ◽

pp. 205-218

Author(s):

Didar K. YESKERMESSOV ◽

Sergey V. PLOTNIKOV ◽

Nazgul K. YERDYBAEVA

Keyword(s):

Mechanical Properties ◽

Protective Coatings ◽

Cutting Tools ◽

Experimental Studies ◽

Scratch Test ◽

Vacuum Arc ◽

Properties Of Coatings ◽

Microstructure And Mechanical Properties ◽

Vacuum Arc Deposition ◽

Arc Deposition

Investigated multicomponent coating nitride (Ti-Zr-Cr-Nb)N in this study were obtained using a well-developed technique of vacuum-arc deposition. Theoretical and experimental studies show that the chemical composition, microstructure, and mechanical properties of coatings are based closely on deposition parameters (the working gas pressure and bias potential on the substrate). The microstructure and mechanical properties (Ti-Zr-Cr-Nb)N coatings were investigated using a scanning electron microscope (SEM) equipped with energy dispersive microanalysis prefix and X-ray diffraction (XRD). Phase analysis of nitride coatings (Zr-Ti-Cr-Nb)N indicates a TiN phase, NbTiN2, ZrTiNb, ZrNb, TiCr and α-Ti. The coatings thickness reached 6.8 μm and their maximum of hardness was H = 43,7GPa. Tribological (test “ball-on-disc”) and mechanical (scratch test) properties of multi-coating were studied. The experimental results obtained by studying multicomponent coatings (Ti-Zr-Cr-Nb)N are promising and can be used as protective coatings for cutting tools and structural materials.

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Faculty Opinions recommendation of Large-scale mechanical properties of Xenopus embryonic epithelium.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.8736956.9251054 ◽

2011 ◽

Author(s):

Deborah Leckband

Keyword(s):

Mechanical Properties ◽

Large Scale ◽

Embryonic Epithelium

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Solid Lipid Nanoparticles: A Promising Drug Delivery Technology

International Journal of Pharmaceutical Sciences and Nanotechnology ◽

10.37285/ijpsn.2009.2.2.3 ◽

2009 ◽

Vol 2 (2) ◽

pp. 509-516

Author(s):

S. Pragati ◽

S. Kuldeep ◽

S. Ashok ◽

M. Satheesh

Keyword(s):

Drug Delivery ◽

Solid Lipid Nanoparticles ◽

Large Scale ◽

Colloidal Particles ◽

Scale Up ◽

Lipid Nanoparticles ◽

Scale Production ◽

Research Activity ◽

New Approach ◽

Solid Lipid

One of the situations in the treatment of disease is the delivery of efficacious medication of appropriate concentration to the site of action in a controlled and continual manner. Nanoparticle represents an important particulate carrier system, developed accordingly. Nanoparticles are solid colloidal particles ranging in size from 1 to 1000 nm and composed of macromolecular material. Nanoparticles could be polymeric or lipidic (SLNs). Industry estimates suggest that approximately 40% of lipophilic drug candidates fail due to solubility and formulation stability issues, prompting significant research activity in advanced lipophile delivery technologies. Solid lipid nanoparticle technology represents a promising new approach to lipophile drug delivery. Solid lipid nanoparticles (SLNs) are important advancement in this area. The bioacceptable and biodegradable nature of SLNs makes them less toxic as compared to polymeric nanoparticles. Supplemented with small size which prolongs the circulation time in blood, feasible scale up for large scale production and absence of burst effect makes them interesting candidates for study. In this present review this new approach is discussed in terms of their preparation, advantages, characterization and special features.

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Recombinant Protein Production in Microalgae: Emerging Trends

Protein and Peptide Letters ◽

10.2174/0929866526666191014124855 ◽

2020 ◽

Vol 27 (2) ◽

pp. 105-110 ◽

Cited By ~ 4

Author(s):

Niaz Ahmad ◽

Muhammad Aamer Mehmood ◽

Sana Malik

Keyword(s):

Chloroplast Genome ◽

Recombinant Proteins ◽

Large Scale ◽

Higher Plants ◽

Scale Up ◽

Chloroplast Transformation ◽

Point Of View ◽

Nuclear Transformation ◽

Scale Production ◽

Algal Chloroplast

: In recent years, microalgae have emerged as an alternative platform for large-scale production of recombinant proteins for different commercial applications. As a production platform, it has several advantages, including rapid growth, easily scale up and ability to grow with or without the external carbon source. Genetic transformation of several species has been established. Of these, Chlamydomonas reinhardtii has become significantly attractive for its potential to express foreign proteins inexpensively. All its three genomes – nuclear, mitochondrial and chloroplastic – have been sequenced. As a result, a wealth of information about its genetic machinery, protein expression mechanism (transcription, translation and post-translational modifications) is available. Over the years, various molecular tools have been developed for the manipulation of all these genomes. Various studies show that the transformation of the chloroplast genome has several advantages over nuclear transformation from the biopharming point of view. According to a recent survey, over 100 recombinant proteins have been expressed in algal chloroplasts. However, the expression levels achieved in the algal chloroplast genome are generally lower compared to the chloroplasts of higher plants. Work is therefore needed to make the algal chloroplast transformation commercially competitive. In this review, we discuss some examples from the algal research, which could play their role in making algal chloroplast commercially successful.

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Control of humping phenomenon and analyzing mechanical properties of Al–Si wire-arc additive manufacturing fabricated samples using cold metal transfer process

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

10.1177/0954406221998402 ◽

2021 ◽

pp. 095440622199840

Author(s):

Yashwant Koli ◽

N Yuvaraj ◽

Aravindan Sivanandam ◽

Vipin

Keyword(s):

Mechanical Properties ◽

Additive Manufacturing ◽

Heat Input ◽

Large Scale ◽

High Deposition Rate ◽

Bead Geometry ◽

Layer By Layer ◽

Cold Metal Transfer ◽

Geometrical Shapes ◽

Wire Arc Additive Manufacturing

Nowadays, rapid prototyping is an emerging trend that is followed by industries and auto sector on a large scale which produces intricate geometrical shapes for industrial applications. The wire arc additive manufacturing (WAAM) technique produces large scale industrial products which having intricate geometrical shapes, which is fabricated by layer by layer metal deposition. In this paper, the CMT technique is used to fabricate single-walled WAAM samples. CMT has a high deposition rate, lower thermal heat input and high cladding efficiency characteristics. Humping is a common defect encountered in the WAAM method which not only deteriorates the bead geometry/weld aesthetics but also limits the positional capability in the process. Humping defect also plays a vital role in the reduction of hardness and tensile strength of the fabricated WAAM sample. The humping defect can be controlled by using low heat input parameters which ultimately improves the mechanical properties of WAAM samples. Two types of path planning directions namely uni-directional and bi-directional are adopted in this paper. Results show that the optimum WAAM sample can be achieved by adopting a bi-directional strategy and operating with lower heat input process parameters. This avoids both material wastage and humping defect of the fabricated samples.

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Expanding the boundaries of learning

Phi Delta Kappan ◽

10.1177/00317217211013930 ◽

2021 ◽

Vol 102 (8) ◽

pp. 8-13

Author(s):

Thomas Hatch

Keyword(s):

Instructional Practices ◽

New Hampshire ◽

Large Scale ◽

Educational Experiences ◽

Scale Up ◽

Project Based Learning

Taking advantage of the possibilities for learning outside of school requires us to build on what we know about why it is so hard to sustain and scale up unconventional educational experiences within conventional schools. To illustrate the opportunities and challenges, Thomas Hatch describes a large-scale approach to project-based learning developed in a camp in New Hampshire and incorporated in a Brooklyn school, a trip-based program in Detroit, and Singapore’s systemic embrace of learning outside school. By understanding the conditions that can sustain alternative instructional practices, educators can find places to challenge the boundaries of schooling and create visions of the possible that exceed current constraints.

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Scaling Up Delivery of Biofortified Staple Food Crops Globally: Paths to Nourishing Millions

Food and Nutrition Bulletin ◽

10.1177/0379572120982501 ◽

2021 ◽

pp. 037957212098250

Author(s):

Jennifer K. Foley ◽

Kristina D. Michaux ◽

Bho Mudyahoto ◽

Laira Kyazike ◽

Binu Cherian ◽

...

Keyword(s):

Pearl Millet ◽

Large Scale ◽

Scale Up ◽

Lessons Learned ◽

Raw Material ◽

Micronutrient Deficiencies ◽

Seed Systems ◽

Public And Private ◽

Context Specific ◽

Public And Private Sector

Background: Micronutrient deficiencies affect over one quarter of the world’s population. Biofortification is an evidence-based nutrition strategy that addresses some of the most common and preventable global micronutrient gaps and can help improve the health of millions of people. Since 2013, HarvestPlus and a consortium of collaborators have made impressive progress in the enrichment of staple crops with essential micronutrients through conventional plant breeding. Objective: To review and highlight lessons learned from multiple large-scale delivery strategies used by HarvestPlus to scale up biofortification across different country and crop contexts. Results: India has strong public and private sector pearl millet breeding programs and a robust commercial seed sector. To scale-up pearl millet, HarvestPlus established partnerships with public and private seed companies, which facilitated the rapid commercialization of products and engagement of farmers in delivery activities. In Nigeria, HarvestPlus stimulated the initial acceptance and popularization of vitamin A cassava using a host of creative approaches, including “crowding in” delivery partners, innovative promotional programs, and development of intermediate raw material for industry and novel food products. In Uganda, orange sweet potato (OSP) is a traditional subsistence crop. Due to this, and the lack of formal seed systems and markets, HarvestPlus established a network of partnerships with community-based nongovernmental organizations and vine multipliers to popularize and scale-up delivery of OSP. Conclusions: Impact of biofortification ultimately depends on the development of sustainable markets for biofortified seeds and products. Results illustrate the need for context-specific, innovative solutions to promote widespread adoption.

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Improving the microstructure and mechanical properties of laser cladded Ni-based alloy coatings by changing their composition: A review

REVIEWS ON ADVANCED MATERIALS SCIENCE ◽

10.1515/rams-2020-0027 ◽

2020 ◽

Vol 59 (1) ◽

pp. 340-351

Author(s):

Lin Yinghua ◽

Ping Xuelong ◽

Kuang Jiacai ◽

Deng Yingjun

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Corrosion Resistance ◽

Rare Earth ◽

Composite Coatings ◽

Single Element ◽

Properties Of Coatings ◽

Hard Particles ◽

Microstructure And Mechanical Properties ◽

Nickel Based Alloy

AbstractNi-based alloy coatings prepared by laser cladding has high bonding strength, excellent wear resistance and corrosion resistance. The mechanical properties of coatings can be further improved by changing the composition of alloy powders. This paper reviewed the improved microstructure and mechanical properties of Ni-based composite coatings by hard particles, single element and rare earth elements. The problems that need to be solved for the particle-reinforced nickel-based alloy coatings are pointed out. The prospects of the research are also discussed.

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