Additive manufacturing of Csf/SiC composites with high fiber content by direct ink writing and liquid silicon infiltration

Purpose The purpose of this paper is to provide additive manufacturing-based solutions for preparation of elastomeric foam with broaden compressive stress plateau. Design/methodology/approach Mechanic models are developed for obtaining designs of foam cell units with enhanced elastic buckling. An experimental approach is taken to fabricate the foams based on direct ink writing technique. Experimental and simulation data are collected to assist understanding of our proposals and solutions. Findings A simple tetragonal structured elastomeric foam is proposed and fabricated by direct ink writing, in which its cell unit is theoretically designed by repeating every four filament layers. The foam exhibits a broader stress plateau, because of the pronounced elastic buckling under compressive loading as predicted by the authors’ mechanic modeling. A two-stage stress plateaus as observed in the foam, being attributed to the dual elastic buckling of the cell units along two lateral directions of the XY plane during compression. Research limitations/implications Future work should incorporate more microscopic parameters to tune the elastomeric foam for mechanic performance testing on linear elastic deformation and densification of polymer matrix. Practical implications Additive manufacturing offers an alternative to fabricate elastomeric foam with controlled cell unit design and therefore mechanics. Our results comment on its broad space for development such superior cushioning or damping material in the fields of vibration and energy absorption. Originality/value This work has contributed to new knowledge on preparation of high performance elastomeric foam by providing a better understanding on its cell structure, being printed using direct ink writing machines.

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Worldwide gene pool of fiber flax at VIR, and breeding of rust-resistant varieties

PROCEEDINGS ON APPLIED BOTANY GENETICS AND BREEDING ◽

10.30901/2227-8834-2020-2-57-64 ◽

2020 ◽

Vol 181 (2) ◽

pp. 57-64

Author(s):

S. N. Kutuzova ◽

E. A. Porokhovinova ◽

N. B. Brutch ◽

A. V. Pavlov

Keyword(s):

Rust Resistance ◽

Source Material ◽

Fiber Content ◽

High Yield ◽

Present Moment ◽

R Genes ◽

Fiber Flax ◽

High Fiber ◽

Flax Cultivar ◽

Almost All

Background. There are strict requirements for a modern flax cultivar. It must have a whole set of valuable characters, including rust resistance.Materials and methods. The flax collection of 2485 accessions held by VIR was evaluated using artificial provocative infection.Results. Almost all domestic and foreign accessions and varieties collected before 1957 were highly or extremely susceptible to rust. Five Russian kryazhs1 and cv. ‘GDS-3’ developed at VIR were found to retain rust resistance up to the present moment. Lines derived from them and from three foreign varieties, with an identified number of the original effective R genes, were submitted to breeders. Nineteen donors with a set of economically useful traits, analogous to cvs. ‘Orshansky 2’ and ‘Prizyv 81’ and carrying the same genes, were produced and distributed to breeders. The VIR collection holds 10 donors of rust resistance with high fiber content developed at the All-Russian Research Institute of Flax. Some donors of resistance to other diseases released by the same Institute also possess high rust resistance, thus forming a rich stock of source material. The first cultivar relatively resistant to rust (‘L-1120’) was released in 1951. Possessing polygenic resistance, it was also resistant to Fusarium wilt and lodging, so it was widely used for breeding other cultivars with similar characteristics. As their cultivation expanded, the harvest losses caused by rust dropped. The first rust-resistant cultivar with oligogenic resistance (‘Tomsky 16’) appeared in 1990. By now, many cultivars protected by R genes of rust resistance have been developed. They combine this trait with resistance to Fusarium and lodging, high yield, and high fiber content. Flax rust incidence is not a problem anymore.Conclusion. Plant breeders have at their disposal a rich stock of source material preserved in the VIR collection to produce resistant flax cultivars. The use of rust resistance donors in hybridization cannot disrupt the most important properties of a cultivar.

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Direct ink writing of organic and carbon aerogels

Materials Horizons ◽

10.1039/c8mh00603b ◽

2018 ◽

Vol 5 (6) ◽

pp. 1166-1175 ◽

Cited By ~ 22

Author(s):

Swetha Chandrasekaran ◽

Bin Yao ◽

Tianyu Liu ◽

Wang Xiao ◽

Yu Song ◽

...

Keyword(s):

Additive Manufacturing ◽

Ion Transport ◽

Carbon Aerogels ◽

Direct Ink Writing ◽

3D Printed ◽

Fast Ion ◽

Large Capacitance

Additive manufacturing is used to overcome inherent aerogel limitations. 3D printed aerogels simultaneously exhibit large capacitance and fast ion transport in millimeter-thick electrodes.

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Simultaneous saccharification and co-fermentation of glucose and xylose in steam-pretreated corn stover at high fiber content with Saccharomyces cerevisiae TMB3400

Journal of Biotechnology ◽

10.1016/j.jbiotec.2006.05.001 ◽

2006 ◽

Vol 126 (4) ◽

pp. 488-498 ◽

Cited By ~ 167

Author(s):

Karin Öhgren ◽

Oskar Bengtsson ◽

Marie F. Gorwa-Grauslund ◽

Mats Galbe ◽

Bärbel Hahn-Hägerdal ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Corn Stover ◽

Fiber Content ◽

High Fiber ◽

Pretreated Corn Stover ◽

Simultaneous Saccharification

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Additive manufacturing of composites made of epoxy resin with magnetite particles fabricated with the direct ink writing technique

Journal of Composite Materials ◽

10.1177/0021998319865019 ◽

2019 ◽

Vol 54 (5) ◽

pp. 647-657 ◽

Cited By ~ 2

Author(s):

Jose J Restrepo ◽

Henry A Colorado

Keyword(s):

Additive Manufacturing ◽

Epoxy Resin ◽

Large Scale ◽

Distribution Density ◽

Particulate Composites ◽

Resin Matrix ◽

Direct Ink Writing ◽

Composites Materials ◽

Structural Applications ◽

Magnetite Particles

In this investigation, particulate composites materials made of epoxy resin matrix with magnetite particles were fabricated via additive manufacturing with the direct ink writing technique. Magnetite is an inexpensive material and the direct ink writing process is not only inexpensive but also easy to adapt to any material. A total of eight formulations were investigated, from which only four were feasible for the printing process: 32.6, 33.6, 35.4 and 41 wt.% of particles. The composites were characterized by scanning electron microscopy, compressive strength, particle size distribution, density, and ductility. Results showed that composites exhibit very competitive mechanical properties even though the process was not vacuum assisted, therefore enabling them to be used in large scale and in other structural applications. Composite can be used in electromagnetic shielding.

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The Choice of Bread: The Association between Consumers’ Awareness of Dietary Fiber and Declared Intentions to Eat

Nutrients ◽

10.3390/nu12020360 ◽

2020 ◽

Vol 12 (2) ◽

pp. 360

Author(s):

Marzena Jezewska-Zychowicz ◽

Maria Królak

Keyword(s):

Dietary Fiber ◽

Rural Areas ◽

Fiber Content ◽

Purchase Decision ◽

Sunflower Seeds ◽

Cross Sectional Survey ◽

Cross Sectional ◽

High Fiber ◽

Low Incomes ◽

Selection Of

The objective of the study was to find whether consumers declare an intention to eat bread enriched with fiber in the situation of availability of a plain bread and plain bread with grains, and how these intentions are related to their awareness of fiber in bread. The data were collected in a cross-sectional survey among 1014 Polish adults. Based on three pictures of rolls: plain wheat roll (CR), roll enriched with 12% fiber (RF), and roll topped with sunflower seeds (RSS), the participants’ perception regarding fiber content and its impact on intentions to eat were assessed. The respondents were not informed about the differences in composition of the rolls. Although RSS contained only slightly more fiber (0.98 g) than CR (0.81 g), and much less than RF (3.08 g), most of the respondents indicated RSS as containing the most fiber (50.8%) and declared their intention to eat it (39.0%). Respondents who pointed out the importance of fiber, and grains or wholemeal flour addition when making purchase decision, were more likely to declare an intention to eat RSS compared with CR. The low interest in fiber content in a diet increased the chances of declaring an intention to eat CR and RF. People less educated and with low incomes were more likely to declare an intention to eat CR rather than RSS. While people from rural areas were more likely to choose RSS compared with CR and RF. In conclusion, there is interest in bread enriched with fiber, but consumers experience difficulties in recognizing it. Declared intentions to eat each rolls were determined to the greatest extent by the perception of the roll as source of fiber. Thus, educational activities should be focused on consumers’ perception of fiber-rich products and their skills related to the selection of high-fiber foods.

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3D printed gradient index glass optics

Science Advances ◽

10.1126/sciadv.abc7429 ◽

2020 ◽

Vol 6 (47) ◽

pp. eabc7429

Author(s):

Rebecca Dylla-Spears ◽

Timothy D. Yee ◽

Koroush Sasan ◽

Du T. Nguyen ◽

Nikola A. Dudukovic ◽

...

Keyword(s):

Refractive Index ◽

Additive Manufacturing ◽

Flat Glass ◽

Gradient Index ◽

Direct Ink Writing ◽

Optical Functions ◽

3D Printed ◽

Gradient Refractive Index ◽

Compositional Gradients ◽

Glass Optics

We demonstrate an additive manufacturing approach to produce gradient refractive index glass optics. Using direct ink writing with an active inline micromixer, we three-dimensionally print multimaterial green bodies with compositional gradients, consisting primarily of silica nanoparticles and varying concentrations of titania as the index-modifying dopant. The green bodies are then consolidated into glass and polished, resulting in optics with tailored spatial profiles of the refractive index. We show that this approach can be used to achieve a variety of conventional and unconventional optical functions in a flat glass component with no surface curvature.

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