scholarly journals Controlled deposition of magnetic particles within the 3-D template of wood: making use of the natural hierarchical structure of wood

RSC Advances ◽  
2014 ◽  
Vol 4 (67) ◽  
pp. 35678-35685 ◽  
Author(s):  
Stacy Trey ◽  
Richard T. Olsson ◽  
Valter Ström ◽  
Lars Berglund ◽  
Mats Johansson
Keyword(s):  
Cell Wall ◽  
Cross Section ◽  
Hierarchical Structure ◽  
Wood Sample ◽  
Magnetic Particles ◽  
Magnetic Particle ◽  
Metal Salts ◽  
Wood Veneer ◽  
Controlled Deposition ◽  
Modified Wood

Process of modifying wood veneer samples with metal salts to result in magnetic particle modified wood and images of the cross section of a wood sample lumen cell wall unmodified and modified with the deposition of magnetic particles.

scholarly journals Enhancement of the physical and mechanical properties of wood using a novel organo-montmorillonite/hyperbranched polyacrylate emulsion

Holzforschung ◽  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Jianfeng Xu ◽  
Xiaoyan Li ◽  
Ling Long ◽  
Ru Liu
Keyword(s):  
Mechanical Properties ◽  
Cell Wall ◽  
Pinus Radiata ◽  
Wood Sample ◽  
Wood Cell Wall ◽  
Physical And Mechanical Properties ◽  
Radiata Pine ◽  
Compact Structure ◽  
Populus Cathayana ◽  
Modified Wood

AbstractIn this work, a novel waterborne hyperbranched polyacrylate (HBPA) dispersed organo-montmorillonite (OMMT) emulsion was synthesized and used for the treatment of wood in a vacuum environment in order to enhance the physical and mechanical properties of the wood. The sapwood of Cathay poplar (Populus cathayana Rehd.) and Radiata pine (Pinus radiata D.Don) were used as the samples for experimentation. The results showed that the physical and mechanical properties of the wood improved significantly due to the successful penetration of the OMMT and HBPA into the wood cell wall. From it was also observed that OMET completely exfoliated from the HBPA matrix and formed a hydrophobic film covering on the inside walls of the cell lumen. Further, it was observed that the poplar sample displayed better mechanical properties than the pine sample because the pine has a more compact structure when compared to poplar and contains rosin. Furthermore, it was also observed that the mechanical properties of the modified wood sample gradually improved with an increase in the concentration of the emulsion. However, excessive concentration (>4 wt%) did not lead to further improvement.

scholarly journals Optical Imaging of Magnetic Particle Cluster Oscillation and Rotation in Glycerol

2021 ◽  
Vol 7 (5) ◽  
pp. 82
Author(s):  
River Gassen ◽  
Dennis Thompkins ◽  
Austin Routt ◽  
Philippe Jones ◽  
Meghan Smith ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Magnetic Particles ◽  
Magnetic Particle ◽  
Barium Hexaferrite ◽  
Optical Microscope ◽  
Simplified Model ◽  
Particle Cluster ◽  
Average Deviation ◽  
Cross Sectional

Magnetic particles have been evaluated for their biomedical applications as a drug delivery system to treat asthma and other lung diseases. In this study, ferromagnetic barium hexaferrite (BaFe12O19) and iron oxide (Fe3O4) particles were suspended in water or glycerol, as glycerol can be 1000 times more viscous than water. The particle concentration was 2.50 mg/mL for BaFe12O19 particle clusters and 1.00 mg/mL for Fe3O4 particle clusters. The magnetic particle cluster cross-sectional area ranged from 15 to 1000 μμm2, and the particle cluster diameter ranged from 5 to 45 μμm. The magnetic particle clusters were exposed to oscillating or rotating magnetic fields and imaged with an optical microscope. The oscillation frequency of the applied magnetic fields, which was created by homemade wire spools inserted into an optical microscope, ranged from 10 to 180 Hz. The magnetic field magnitudes varied from 0.25 to 9 mT. The minimum magnetic field required for particle cluster rotation or oscillation in glycerol was experimentally measured at different frequencies. The results are in qualitative agreement with a simplified model for single-domain magnetic particles, with an average deviation from the model of 1.7 ± 1.3. The observed difference may be accounted for by the fact that our simplified model does not include effects on particle cluster motion caused by randomly oriented domains in multi-domain magnetic particle clusters, irregular particle cluster size, or magnetic anisotropy, among other effects.

Development of a bacterial DNA extraction modular chip using a magnetic particle and portable vibration motor

2020 ◽  
Vol 12 (9) ◽  
pp. 1197-1202
Author(s):  
Sun Young Lim ◽  
Tae Jae Lee ◽  
Seol Yi Shin ◽  
Nam Ho Bae ◽  
Seok Jae Lee ◽  
...  
Keyword(s):  
Power System ◽  
Electric Power ◽  
Dna Extraction ◽  
Magnetic Particles ◽  
Magnetic Particle ◽  
Electric Power System ◽  
Bacterial Dna ◽  
System P ◽  
3D Printed ◽  
Bacterial Dna Extraction

The bacterial DNA was simply purified by magnetic particles with a portable vibration motor. To effectively extract DNA in the field, the 3D-printed device was employed with low electric power system.

A light and electron microscope investigation of the transfer cell region of maize caryopses

1990 ◽  
Vol 68 (3) ◽  
pp. 471-479 ◽  
Author(s):  
Ronald W. Davis ◽  
J. D. Smith ◽  
B. Greg Cobb
Keyword(s):  
Cell Wall ◽  
Cross Section ◽  
Close Association ◽  
Transfer Cells ◽  
Transfer Cell ◽  
Cell Region ◽  
Maternal Tissue ◽  
X Ray ◽  
Numerous Cell ◽  
Electron Microscopes

The transfer cell zones from 23-day postpollination corn caryopses were examined using light and electron microscopes and X-ray elemental analysis. The transfer cells were sectioned in cross and longitudinal planes and were characterized by having numerous cell-wall extensions in the form of anastomosing lamellae. The most basal transfer cells had more cell-wall extensions than those that were successively deeper in the endosperm. Cytoplasm, rich with mitochondria, filled the interstices of cell-wall extensions, and many vesiculate areas could be found along the plasma membrane. Some transfer cells contained crystals within plastids. The crystals were composed of magnesium, phosphorus, calcium, and zinc. Other cells had large aggregations of endoplasmic reticulum that were often in close association with mitochondria or unidentified, single membrane bounded organelles. When viewed in cross section, the cell-wall extensions of contiguous cells tended to originate from common loci. Plasmodesmata were absent in the bottom parts of the basal transfer cells where they contacted the maternal tissue but were abundant in the upper parts of these cells and in the transfer cells found deeper in the endosperm. The plasmodesmata were found in clusters and alternated with the wall extension areas.

Gold Magnetic Particle Based Immunoassay on a Disposable Microchips

2011 ◽  
Vol 236-238 ◽  
pp. 1931-1934
Author(s):  
Zi Ye Wang ◽  
Kang Wang ◽  
Xue Mei Ma
Keyword(s):  
Magnetic Nanoparticles ◽  
Reaction Time ◽  
Laser Ablation ◽  
Magnetic Particles ◽  
Magnetic Particle ◽  
Binding Assay ◽  
Igg Binding

Microchips appear to offer important opportunities for modern research. Microchips based on gold magnetic nanoparticles make manipulation of biomolecules more conveniently, and has the advantage of deducing reaction time. In this study, we first achieved microchips design and fabrication through CO2 laser ablation for immunoassay, and then conjugated mouse IgG to gold magnetic nanoparticles serve as a target. Finally, HRP labeled goat anti mouse IgG binding assay and substrate reaction were performed with disposable microchips and other devices. The results indicated that the reactions carried on successfully and magnetic particles moved well in chips.

scholarly journals Mode of action of brown rot decay resistance in modified wood: a review

Holzforschung ◽  
2014 ◽  
Vol 68 (2) ◽  
pp. 239-246 ◽  
Author(s):  
Rebecka Ringman ◽  
Annica Pilgård ◽  
Christian Brischke ◽  
Klaus Richter
Keyword(s):  
Cell Wall ◽  
Mode Of Action ◽  
Wood Decay ◽  
Brown Rot ◽  
Decay Resistance ◽  
Hydroxyl Groups ◽  
Decay Fungi ◽  
Brown Rot Decay ◽  
Thermally Modified Wood ◽  
Modified Wood

Abstract Chemically or physically modified wood materials have enhanced resistance to wood decay fungi. In contrast to treatments with traditional wood preservatives, where the resistance is caused mainly by the toxicity of the chemicals added, little is known about the mode of action of nontoxic wood modification methods. This study reviews established theories related to resistance in acetylated, furfurylated, dimethylol dihydroxyethyleneurea-treated, and thermally modified wood. The main conclusion is that only one theory provides a consistent explanation for the initial inhibition of brown rot degradation in modified wood, that is, moisture exclusion via the reduction of cell wall voids. Other proposed mechanisms, such as enzyme nonrecognition, micropore blocking, and reducing the number of free hydroxyl groups, may reduce the degradation rate when cell wall water uptake is no longer impeded.

Synthesis of transparent magnetic particle/organic hybrid film using iron–organics

2000 ◽  
Vol 15 (10) ◽  
pp. 2114-2120 ◽  
Author(s):  
Toshinobu Yogo ◽  
Tomoyuki Nakamura ◽  
Wataru Sakamoto ◽  
Shin-ichi Hirano
Keyword(s):  
Iron Oxide ◽  
Magnetization Curve ◽  
Magnetic Particles ◽  
Magnetic Particle ◽  
Hybrid Film ◽  
Oxide Particle ◽  
Iron Oxide Particle ◽  
Organic Hybrid ◽  
Hydrolysis Conditions

A transparent magnetic particle/organic film was synthesized from an iron–organic compound. Iron(III) 3-allylacetylacetonate (IAA) was polymerized followed by in situ hydrolysis yielding an iron oxide particle/oligomer hybrid. The sizes of magnetic particles were dependent upon the hydrolysis conditions of the IAA oligomers. A nanometer-sized ferrimagnetic iron oxide particle/oligomer hybrid showed a magnetization curve with no coercive force at 300 K and that with Hc of 200 Oe at 4.2 K, respectively. The magnetization versus H/T curves at 300 and 77 K were superimposed on each other and satisfied the Langevin equation. The transparent hybrid film showed a magnetization curve at room temperature. The absorption spectrum of the film was shifted to higher energy by 0.14 eV compared with that of bulk magnetite. The absorption edge of the film was blue-shifted.

scholarly journals Preliminary Study on the Physical and Mechanical Properties of Poplar Wood Modified by Waterborne Glucose Silicone Resin

2020 ◽  
Author(s):  
Qiangqiang Liu ◽  
Haojia Du ◽  
Wenhua Lyu
Keyword(s):  
Mechanical Properties ◽  
Cell Wall ◽  
Mass Fraction ◽  
Untreated Wood ◽  
Physical And Mechanical Properties ◽  
Silicone Resin ◽  
Poplar Wood ◽  
Characteristic Structure ◽  
Organic Hybrid ◽  
Modified Wood

In order to improve the performance of soft plantation wood, an environmentally friendly inorganic-organic hybrid wood modifier was developed. First, using urea and melamine as crosslinking agents, the waterborne glucose silicone resin (MUG) was prepared with glucose under the catalysis of inorganic acid and metal ions. Then MUG resin was diluted to 10% and 20% mass fraction, and compounded with sodium silicate (S) of 20% and 10% mass fraction, so the inorganic-organic hybrid G10S20 and G20S10 wood modifier were obtained respectively. Then plantation poplar wood (Populus tomentosa) were impregnated and modified with them. Their physical and mechanical properties were tested and compared with those of the wood treated with S of 20% mass fraction (S20). Infrared analysis showed that amino resin characteristic structure (CO-NH-) existed in MUG resin. The resin has good permeability. Compared with S20 modified wood, the degree of shrinkage of G10S20 or G20S10 modified wood is reduced, their moisture absorption is reduced, and their dimensional stability is improved. Waterborne glucose silicone modifier can effectively improve the wood density, modulus of elasticity, modulus of rapture and compression strength. SEM analysis showed that the cell wall of G20S10 modified wood was significantly thicker than the untreated wood, and there were columnar and granular solid substances attached in some cell cavities, ducts and corners, etc. EDX showed that the number of Si elements on the cell wall was significantly increased compared with the control, indicating that the modifier effectively entered the wood cell wall. The waterborne glucose silicone resin can greatly improve the physical and mechanical properties of wood through organic-inorganic hybridization. It is a green, non-formaldehyde, eco-friendly, low cost, compound wood modifier with broad application prospects.

scholarly journals Reviewing Magnetic Particle Preparation: Exploring the Viability in Biosensing

Sensors ◽  
2020 ◽  
Vol 20 (16) ◽  
pp. 4596
Author(s):  
Daniel Kappe ◽  
Laila Bondzio ◽  
Joris Swager ◽  
Andreas Becker ◽  
Björn Büker ◽  
...  
Keyword(s):  
Magnetic Particles ◽  
Magnetic Particle ◽  
Size Range ◽  
Particle System ◽  
Microfluidic Channel ◽  
Review Article ◽  
Particle Systems ◽  
Heusler Compound ◽  
Particle Preparation ◽  
New Applications

In this review article, we conceptually investigated the requirements of magnetic nanoparticles for their application in biosensing and related them to example systems of our thin-film portfolio. Analyzing intrinsic magnetic properties of different magnetic phases, the size range of the magnetic particles was determined, which is of potential interest for biosensor technology. Different e-beam lithography strategies are utilized to identify possible ways to realize small magnetic particles targeting this size range. Three different particle systems from 500 μm to 50 nm are produced for this purpose, aiming at tunable, vertically magnetized synthetic antiferromagnets, martensitic transformation in a single elliptical, disc-shaped Heusler Ni50Mn32.5Ga17.5 particle and nanocylinders of Co2MnSi-Heusler compound. Perspectively, new applications for these particle systems in combination with microfluidics are addressed. Using the concept of a magnetic on–off ratchet, the most suitable particle system of these three materials is validated with respect to magnetically-driven transport in a microfluidic channel. In addition, options are also discussed for improving the magnetic ratchet for larger particles.

Sign in / Sign up

Export Citation Format

Share Document