Ion cross-linking assisted synthesis ZIF-8/chitosan/melamine sponge with anti-biofouling activity for enhanced uranium recovery

Author(s):  
Xuejie Guo ◽  
Haocheng Yang ◽  
Jun Wang

Micro/mesoporous powders structure and marine microorganisms biofouling directly limited the potential of ZIFs in uranium recovery from seawater. Herein, an anti-biofouling ZIF-8/chitosan/melamine sponge adsorbent (CFZ8) with three-dimensional porous structure was...

1998 ◽  
Vol 4 (S2) ◽  
pp. 32-33
Author(s):  
M. F. Schmid ◽  
P. Matsudaira ◽  
M. T. Dougherty ◽  
M. B. Sherman ◽  
C. Henn ◽  
...  

Collaboration between local microscopists and image processing specialists, and their remote biological colleagues, has been hampered by the difficulty of i) transferring the three-dimensional reconstructions of macromolecules resulting from the cryomicroscopy and image processing, ii) viewing the results in a meaningful way, and iii) communicating the results and the interpretations derived therefrom to each other.The acrosomal process is an intracellular quasi-crystalline organelle in the head of the sperm of the horseshoe crab Limulus polyphemus. It consists of 100 - 130 actin-scruin filaments packed together in a pseudo-hexagonal lattice and is up to 60 μm long with a diameter of 0.1 μm. Scruin-scruin interactions are responsible for cross-linking the actin filaments together in the bundle. Our goal was to reveal interfilament interactions in the bundle. We have taken tilt series images in the electron microscope to reconstruct its three-dimensional structure at 45 Å resolution.


CrystEngComm ◽  
2015 ◽  
Vol 17 (48) ◽  
pp. 9336-9347 ◽  
Author(s):  
Jingyun Ma ◽  
Longwei Yin ◽  
Tairu Ge

We report on the rational design and synthesis of three dimensional (3D) Cu-doped NiO architectures with an adjustable chemical component, surface area, and hierarchically porous structure as anodes for lithium ion battery.


2018 ◽  
Vol 4 (10) ◽  
pp. eaat7629 ◽  
Author(s):  
Hiroaki Gotoh ◽  
Chang Liu ◽  
Abu Bin Imran ◽  
Mitsuo Hara ◽  
Takahiro Seki ◽  
...  

An elastomer is a three-dimensional network with a cross-linked polymer chain that undergoes large deformation with a small external force and returns to its original state when the external force is removed. Because of this hyperelasticity, elastomers are regarded as one of the best candidates for the matrix material of soft robots. However, the comprehensive performance required of matrix materials is a special challenge because improvement of some matrix properties often causes the deterioration of others. For example, an improvement in toughness can be realized by adding a large amount of filler to an elastomer, but to the impairment of optical transparency. Therefore, to produce an elastomer exhibiting optimum properties suitable for the desired purpose, very elaborate, complicated materials are often devised. Here, we have succeeded in creating an optically transparent, easily fabricated elastomer with good extensibility and high toughness by using a polyrotaxane (PR) composed of cyclic molecules and a linear polymer as a cross-linking agent. In general, elastomers having conventional cross-linked structures are susceptible to breakage as a result of loss of extensibility at high cross-linking density. We found that the toughness of the transparent elastomer prepared using the PR cross-linking agent is enhanced along with its Young’s modulus as cross-linking density is increased.


2020 ◽  
Author(s):  
Thaksen Jadhav ◽  
Yuan Fang ◽  
Cheng-Hao Liu ◽  
Afshin Dadvand ◽  
Ehsan Hamzehpoor ◽  
...  

We report the first transformation between crystalline vinylene-linked two-dimensional (2D) polymers and crystalline cyclobutane-linked three-dimensional (3D) polymers. Specifically, absorption-edge irradiation of the 2D poly(arylenevinylene) covalent organic frameworks (COFs) results in topological [2+2] cycloaddition cross-linking the π-stacked layers in 3D COFs. The reaction is reversible and heating to 200°C leads to a cycloreversion while retaining the COF crystallinity. The resulting difference in connectivity is manifested in the change of mechanical and electronic properties, including exfoliation, blue-shifted UV-Vis absorption, altered luminescence, modified band structure and different acid-doping behavior. The Li-impregnated 2D and 3D COFs show a significant ion conductivity of 1.8×10<sup>−4</sup> S/cm and 3.5×10<sup>−5</sup> S/cm, respectively. Even higher room temperature proton conductivity of 1.7×10<sup>-2</sup> S/cm and 2.2×10<sup>-3</sup> S/cm was found for H<sub>2</sub>SO<sub>4</sub>-treated 2D and 3D COFs, respectively.


2021 ◽  
Author(s):  
Stephan Förster ◽  
Jürgen Groll ◽  
Benjamin Reineke ◽  
Stephan Hauschild ◽  
Ilona Paulus ◽  
...  

Bioprinting has evolved into a thriving technology for the fabrication of cell-laden scaffolds. Bioinks are the most critical component for bioprinting. Recently, microgels have been introduced as a very promising bioink enabling cell protection and the control of the cellular microenvironment. However, their microfluidic fabrication inherently seemed to be a limitation. Here we introduce a direct coupling of microfluidics and 3D-printing for the microfluidic production of cell-laden microgels with direct in-flow bioprinting into stable scaffolds. The methodology enables the continuous on-chip encapsulation of cells into monodisperse microdroplets with subsequent in-flow cross-linking to produce cell-laden microgels, which after exiting a microtubing are automatically jammed into thin continuous microgel filaments. The integration into a 3D printhead allows direct in-flow printing of the filaments into free-standing three-dimensional scaffolds. The method is demonstrated for different cross-linking methods and cell lines. With this advancement, microfluidics is no longer a bottleneck for biofabrication. <br>


Author(s):  
Inna Slepchuk ◽  
Olga Ya. Semeshko ◽  
Yuliya G. Saribekova ◽  
Irina N. Kulish ◽  
Igor V. Gorokhov

Results of study of influence of amount of functional groups of glycidyl ethers on characteristics of the spatial grid of crosslinked polyurethane polymer are presented. Parameters of a three-dimensional spatial grid of investigated samples of polymeric films and their physical and mechanical properties were determined by a method of equilibrium swelling in organic solvents.


2021 ◽  
pp. 026248932110536
Author(s):  
Xiao-Ming Zhou ◽  
Yi-Fan Liu

In order to improve the melt strength of Poly(butylene succinate) (PBS) resin, the silane graft-crosslinked PBS copolyester materials were prepared by melt blending method with vinyltriethyl silane as graft material and benzyl peroxide (BPO) as initiator. At the same time, the environmentally friendly compound foaming agent (citric acid and sodium bicarbonate) was used as foaming agent. The results showed that the tensile properties and melt strength of PBS resin were greatly improved after silane grafting and cross-linking, and the graft and cross-linking reaction between PBS resin and silane occurred, forming a three-dimensional space network structure, and the viscosity and elasticity of polymer melt was changed, which increased the entropy elasticity of the material and strengthened the polymer melt strength. The additional amount of compound foaming agent and the cross-linking degree of material had important influence on the diameter and distribution of PBS foaming material.


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