Creation of three-dimensional structures by direct ink writing with kaolin suspensions

2018 ◽  
Vol 6 (42) ◽  
pp. 11392-11400 ◽  
Author(s):  
Qinglei Sun ◽  
Zizhou Yang ◽  
Hao Cheng ◽  
Yang Peng ◽  
Yanqin Huang ◽  
...  
Keyword(s):  
Science And Technology ◽  
Three Dimensional ◽  
Direct Ink Writing ◽  
Layer Structures

Three-layer structures of the dried letters into the Huazhong University of Science and Technology “H, U, S and T” shapes.

Finescale Dual-Doppler Analysis of Hurricane Boundary Layer Structures in Hurricane Frances (2004) at Landfall

2014 ◽  
Vol 142 (5) ◽  
pp. 1874-1891 ◽  
Author(s):  
Karen A. Kosiba ◽  
Joshua Wurman
Keyword(s):  
Boundary Layer ◽  
Three Dimensional ◽  
Transient Nature ◽  
Layer Structures ◽  
Characteristic Wavelength ◽  
Doppler Data ◽  
Mean Wind Speed ◽  
Average Flux ◽  
Hurricane Boundary Layer ◽  
The Right

Abstract Two Doppler on Wheels (DOW) mobile radars collected fine-spatial-scale dual-Doppler data in the right-front quadrant and eye of Hurricane Frances (2004) as it made landfall near Stuart, Florida. A 5.7-km dual-Doppler baseline established a dual-Doppler domain south and east of Fort Pierce, Florida, encompassing a 5.5 km × 5.5 km horizontal area, with a grid spacing of 20 m, allowing for the resolution of subkilometer-scale horizontal structures and associated kinematics. Three-dimensional vector wind analyses of the boundary layer revealed the presence of linear coherent structures with a characteristic wavelength of 400–500 m near the surface that increased in size and became more cellular in shape with increasing height. Average horizontal perturbation winds were proportional to average total horizontal winds. Within the eye of the hurricane, the features lost linear coherency despite a high mean wind speed, possibly due to changes in stability. A slight decrease in the characteristic wavelength of boundary layer structures was documented as the winds cross the barrier islands east of Fort Pierce. Vertical flux of horizontal momentum caused by individual vortical structures was substantially higher than values employed in turbulence parameterization schemes, but the domain-wide average flux was substantially lower than that in individual structures, likely due to the transient nature of the most intense portions of the structures. Analysis of the turbulent kinetic energy (TKE) yielded values comparable to those reported in previous observational studies over the open ocean. However, there was substantial variability in TKE within the dual-Doppler domain, emphasizing the challenge in obtaining representative samples using non-3D measurements such as dropsondes.

Epilogue

2016 ◽  
pp. 133-136
Author(s):  
William H. Brock
Keyword(s):  
Combinatorial Chemistry ◽  
Science And Technology ◽  
Three Dimensional ◽  
Structural Models ◽  
Service Science ◽  
Carbon Allotropes ◽  
Scientific Disciplines ◽  
Transdisciplinary Science ◽  
The 1960S

The Epilogue concludes with a brief look at some of the exciting, and more positive, aspects of chemistry since the 1960s: the use of computers to study perfect three-dimensional structural models and design new molecules on the screen; combinatorial chemistry; retrosynthesis; the discoveries of the carbon allotropes fullerene and graphene; and nanotechnology. In an age of cross-disciplinary, transdisciplinary science and technology several historians, sociologists, and philosophers of science have queried whether the concept of distinct scientific disciplines like chemistry, physics, and biology serves a purpose any longer. Has chemistry become a service science, or has chemistry taken over these other disciplines?

Direct writing of porous tissue scaffolds based on Vaseline-doped hydroxyapatite inks

2015 ◽  
Vol 29 (14) ◽  
pp. 1550066
Author(s):  
Ya-Yun Li ◽  
Long-Tu Li ◽  
Bo Li
Keyword(s):  
Human Liver ◽  
Carcinoma Cell ◽  
Three Dimensional ◽  
Tissue Scaffolds ◽  
Liver Carcinoma ◽  
Test Results ◽  
Direct Writing ◽  
Precision Control ◽  
Direct Ink Writing ◽  
Carcinoma Cell Line Hepg2

A novel type of 40 vol.% hydroxyapatite ( HAp ), Ca 10( PO 4)6( OH )2, suspension doped with Vaseline was developed, and porous three-dimensional (3D) scaffolds were fabricated by using a direct ink writing (DIW) method. The preparation of the HAp inks and the principles of the DIW technique were investigated. The microporosity of the scaffold wall increased after introducing the Vaseline, whereas macroporosity can be produced by varying the DIW technique. The micromorphology test results show that the samples sintered at 1150°C for 2 h formed ceramics with a set amount of pores, which benefit cell growth by providing more locations for cells to attach and proliferate. Under a microscope, the proliferations of human liver carcinoma cell line ( HepG2 ) cells can be observed on the 3D HAp scaffolds. The DIW method has the advantages of a rapid process, ease of design and high precision control, potentially inspiring the design and application of biomaterials and scaffolds.

Direct Ink Writing of Three-Dimensional Ceramic Structures

2006 ◽  
Vol 89 (12) ◽  
pp. 3599-3609 ◽  
Author(s):  
Jennifer A. Lewis ◽  
James E. Smay ◽  
John Stuecker ◽  
Joseph Cesarano
Keyword(s):  
Three Dimensional ◽  
Direct Ink Writing

Determination of the structure of 2(benzene-1,3,5-tricarboxylic acid)·1.5(pyrene)·2(methanol) and comparison with that of 2(benzene-1,3,5-tricarboxylic acid)·pyrene·2(ethanol)

2001 ◽  
Vol 57 (5) ◽  
pp. 692-696 ◽  
Author(s):  
Frank H. Herbstein ◽  
Moshe Kapon ◽  
Vitaly Shteiman
Keyword(s):  
Interlayer Space ◽  
Three Dimensional ◽  
Tricarboxylic Acid ◽  
The Other ◽  
Published Data ◽  
Acceptor Interaction ◽  
Layer Structures ◽  
Donor Acceptor ◽  
Graph Set

The structure of the title methanol complex (P\bar 1, Z = 2) has been determined and compared with that of the title ethanol complex (C2/c, Z = 8) using published data. Both complexes have layer structures, the (essentially planar) layers being constructed from rings of six TMA molecules, hydrogen bonded through four `carboxyl dimers' and two `interrupted dimers', where methanol (ethanol) is included in the R^4_4(12) (graph set) ring. The packing of the layers differs in the two complexes, leading to different three-dimensional structures. In the methanol complex, one pyrene molecule is located within the layer and the other, at a centre of symmetry, between the layers in one type of interlayer space, while the methyls of methanol protrude into the other type of interlayer space. In the ethanol complex, the superpositioning of the layers is such that two types of stack are formed; one of these is mixed, containing pyrene and one of the independent TMA molecules in alternating sequence, while the other stack contains only the second type of TMA. Spectroscopic study is needed to establish whether the partial mixed stack arrangement in the crystalline ethanol complex implies donor–acceptor interaction.

scholarly journals Mountains Made in Switzerland: Facts and Concerns in Nineteenth-Century Cartography

2009 ◽  
Vol 22 (3) ◽  
pp. 387-408 ◽  
Author(s):  
Daniel Speich
Keyword(s):  
Nineteenth Century ◽  
Cultural History ◽  
Science And Technology ◽  
Three Dimensional ◽  
Considerable Detail ◽  
Made In

ArgumentCultural history has investigated the appropriation of mountain wilderness in considerable detail, without however systematically including the contributions of science and technology in the process. This paper suggests a way of filling this gap. It argues that cartography was instrumental in giving mountains their modern shape. In the course of the nineteenth century, mountains arguably gained a new factual existence at the intersection of new aesthetic, scientific, economic, and political concerns with landscape. Taking the case of Swiss cartography, the paper shows how mapmakers strived to represent this matter of concern in ever more perfect ways, culminating in the three-dimensional rendering of mountains as plaster reliefs. The paper concludes with the observation that this transformation is to a certain extent irreversible. The mountains made in Switzerland in the nineteenth century are probably here to stay.

Fabrication of 3D photocatalytic α-Fe2O3 structure using direct ink writing method

2014 ◽  
Vol 28 (07) ◽  
pp. 1450051 ◽  
Author(s):  
Yayun Li ◽  
Bo Li ◽  
Longtu Li
Keyword(s):  
Uv Light ◽  
Three Dimensional ◽  
Bulk Sample ◽  
Potential Method ◽  
Optical Microscope ◽  
Solid Content ◽  
X Ray Diffraction ◽  
Direct Ink Writing ◽  
Shaping Process ◽  
Better Than

Three-dimensional (3D) photocatalytic devices are economical and environmental, since they can be easily recycled and reused. In this paper, a kind of 3D photocatalytic device with a rod diameter of 250 μm was fabricated using the aqueous-based α- Fe 2 O 3 ceramic inks by direct ink writing (DIW) method. The properties of the DIW woodpile samples were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and optical microscope. The result shows that the ink with solid content of 71.4 wt.% exhibits a shear thinning behavior and proper viscoelastic properties, which ensure a feasible extrusion in the whole shaping process. The sample sintered at 800°C in air causes photocatalytic degradation of methylene blue (MB) solution under the ultraviolet (UV) light. The photocatalytic properties of the α- Fe 2 O 3 woodpile structure was characterized by the UV-visible light spectrophotometer, and it was found to be better than that of bulk sample with same weight for its higher specific surface. The DIW technique would offer a potential method for the design and fabrication of 3D photocatalytic devices.

X-Ray Structure Determinations of Bromo- and/or Bromomethylsubstituted Benzenes: C–H···Br, C–Br···Br, and C–Br···π Interactions

2012 ◽  
Vol 67 (12) ◽  
pp. 1273-1281 ◽  
Author(s):  
Peter G. Jones ◽  
Piotr Kuś ◽  
Ina Dix
Keyword(s):  
Hydrogen Bonds ◽  
Three Dimensional ◽  
Benzene Derivatives ◽  
Chemical Similarity ◽  
X Ray ◽  
Π Interactions ◽  
Layer Structures ◽  
Structure Determinations ◽  
Subordinate Role

The structures of seven benzene derivatives [1,2,3-tri(bromomethyl)benzene, (1); 3,5- di(bromomethyl)bromobenzene, (2); 2,5-di(bromomethyl)bromobenzene, (3); 4-(bromomethyl)-2,5- dibromotoluene, (4); 4-(bromomethyl)bromobenzene, (5); 2,3-di(bromomethyl)bromobenzene, (6) and (bromomethyl)-p-dibromobenzene, (7)] with bromo and bromomethyl (and in one case methyl) substituents are presented and analysed in terms of Br···Br interactions up to 4.0 A° , supported by hydrogen bonds H···Br. Some interactions of the type Br···π and π···π are encountered and play a subordinate role in the packing. Despite the close chemical similarity of the compounds, some of which are isomers with permuted substituent positions, the packing motifs are highly variable. Compounds 2-5 are based on layer structures with Brn (n=3, 4) and/or mixed Br/C rings. Compounds 1, 6 and 7 display three-dimensional packings of differing complexity, but with interpretable substructures; 1 can be analysed in terms of ribbons of linked Br3 and Br4 rings; 6 displays chains of linked Br3 triangles; 7 consists of ribbons of linked Br4 quadrilaterals.

scholarly journals Polymer-Derived Biosilicate®-like Glass-Ceramics: Engineering of Formulations and Additive Manufacturing of Three-Dimensional Scaffolds

Materials ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5170
Author(s):  
Fulden Dogrul ◽  
Paulina Ożóg ◽  
Martin Michálek ◽  
Hamada Elsayed ◽  
Dušan Galusek ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Additive Manufacturing ◽  
Room Temperature ◽  
Three Dimensional ◽  
Glass Ceramics ◽  
Gas Release ◽  
Carbon Phase ◽  
Digital Light Processing ◽  
Direct Ink Writing ◽  
Additive Manufacturing Technology

Silicone resins, filled with phosphates and other oxide fillers, yield upon firing in air at 1100 °C, a product resembling Biosilicate® glass-ceramics, one of the most promising systems for tissue engineering applications. The process requires no preliminary synthesis of parent glass, and the polymer route enables the application of direct ink writing (DIW) of silicone-based mixtures, for the manufacturing of reticulated scaffolds at room temperature. The thermal treatment is later applied for the conversion into ceramic scaffolds. The present paper further elucidates the flexibility of the approach. Changes in the reference silicone and firing atmosphere (from air to nitrogen) were studied to obtain functional composite biomaterials featuring a carbon phase embedded in a Biosilicate®-like matrix. The microstructure was further modified either through a controlled gas release at a low temperature, or by the revision of the adopted additive manufacturing technology (from DIW to digital light processing).

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