Wooden Nano-Composite Materials and Prospects of their Application in Wooden Housing Construction

2018 ◽  
Vol 931 ◽  
pp. 583-588 ◽  
Author(s):  
Sergey I. Ovsyannikov ◽  
Vladislav Yurevich Dyachenko
Keyword(s):  
Wood Properties ◽  
The Body ◽  
Frame Structure ◽  
Seismic Resistance ◽  
Internal Stresses ◽  
Deep Processing ◽  
Nano Composite ◽  
Wood Structures ◽  
New Class ◽  
Natural Wood

Nano-composite material is a completely new class of material that combines wood pulp and some porous materials of artificial and natural origin. This is an artificially created material consisting of a polymer matrix of the porous natural or synthetic material. The number of micro or macro-pores in the composite can be different for different wood species variety of micro and macro capillaries varying in average from 25 to 35% of the wood volume. The change in wood properties occurs at the structuring of water-insoluble molecules smaller than 3 nm and that is a part of the filler. Industrial technology of deep processing of wood-based nanotechnology allows the manufacture of new products such as laminated wood structures with nano-device that have properties not existing in nature: 1. The wood becomes hydrophobic, it is characterised by almost complete lack of absorption by the body of the wood, which leads to almost full, the lack of swelling and the change of the geometrical sizes of the material; 2. The absence of cracking. As the penetrating substance is evenly distributed between micro and macro pores and uniformly fills all the frame structure, there are additional internal stresses, typical for products made of natural wood; 3. The use of such technology ensures high 10-25% of the density if you increase strength by 20%, which also increases the seismic resistance and mi CNTI products and structures.

scholarly journals Epigenetic Regulation of Cannabinoid-Mediated Attenuation of Inflammation and Its Impact on the Use of Cannabinoids to Treat Autoimmune Diseases

2021 ◽  
Vol 22 (14) ◽  
pp. 7302
Author(s):  
Bryan Latrell Holloman ◽  
Mitzi Nagarkatti ◽  
Prakash Nagarkatti
Keyword(s):  
Autoimmune Diseases ◽  
Chronic Inflammation ◽  
Cannabinoid Receptors ◽  
T Regulatory Cells ◽  
Neurological Diseases ◽  
Suppressor Cells ◽  
The Body ◽  
New Class ◽  
Wide Range ◽  
Clinical Disorders

Chronic inflammation is considered to be a silent killer because it is the underlying cause of a wide range of clinical disorders, from cardiovascular to neurological diseases, and from cancer to obesity. In addition, there are over 80 different types of debilitating autoimmune diseases for which there are no cure. Currently, the drugs that are available to suppress chronic inflammation are either ineffective or overtly suppress the inflammation, thereby causing increased susceptibility to infections and cancer. Thus, the development of a new class of drugs that can suppress chronic inflammation is imperative. Cannabinoids are a group of compounds produced in the body (endocannabinoids) or found in cannabis (phytocannabinoids) that act through cannabinoid receptors and various other receptors expressed widely in the brain and immune system. In the last decade, cannabinoids have been well established experimentally to mediate anti-inflammatory properties. Research has shown that they suppress inflammation through multiple pathways, including apoptosis and inducing immunosuppressive T regulatory cells (Tregs) and myeloid-derived suppressor cells (MDSCs). Interestingly, cannabinoids also mediate epigenetic alterations in genes that regulate inflammation. In the current review, we highlight how the epigenetic modulations caused by cannabinoids lead to the suppression of inflammation and help identify novel pathways that can be used to target autoimmune diseases.

Elastoplastic time history analysis of reinforced engineered cementitious composite or engineered cementitious composite–concrete composite frame under earthquake action

2016 ◽  
Vol 20 (4) ◽  
pp. 491-503 ◽  
Author(s):  
Fang Yuan ◽  
Jinlong Pan ◽  
Christopher KY Leung
Keyword(s):  
Cyclic Loading ◽  
High Performance ◽  
Time History ◽  
Frame Structure ◽  
Dissipated Energy ◽  
Seismic Resistance ◽  
Cementitious Composite ◽  
Engineered Cementitious Composite ◽  
Composite Frame ◽  
Story Drift

Engineered cementitious composite is a class of high-performance cementitious composites with pseudo-strain hardening behavior and excellent crack control capacity. Substitution of concrete with engineered cementitious composite can greatly reduce the cracking and durability problems associated with low tensile strength and brittleness of concrete and can significantly increase structural seismic resistance. In this article, a pair of beam–column joints with various matrix types has been tested under reversed cyclic loading to study the effect of substitution of concrete with engineered cementitious composite in the joint zone on the seismic behaviors of composite members. After that, a simplified constitutive model of engineered cementitious composite under cyclic loading is proposed, and the structural performance of steel reinforced engineered cementitious composite members is simulated by fiber beam elements. The accuracy of the model is verified with test data. Finally, three frame structures with different matrixes subjected to earthquake actions were numerically modeled to verify the contribution of ductile engineered cementitious composite material to structural seismic resistance. The seismic responses or failure mechanisms, deformation patterns, and energy dissipation capacities for each frame structure are analyzed and compared. The simulation results indicate that the application of engineered cementitious composite can reduce the maximum story drift ratio, and the distributions of the dissipated energy are more uniform along the building height when engineered cementitious composite is strategically used in ground columns and beam–column joints of the frame structure. The seismic performance of the reinforced engineered cementitious composite-concrete composite frame is found to be even better than the frame with all concrete replaced by engineered cementitious composite.

STRUCTURAL ANALYSIS OF CARBON COMPOSITE FRAME FOR FOLDABLE ELECTRIC WHEELCHAIR DEVELOPMENT

2019 ◽  
Vol 19 (07) ◽  
pp. 1940045
Author(s):  
WOO SUK CHONG ◽  
MI YEON SHIN ◽  
CHANG HO YU
Keyword(s):  
Structural Analysis ◽  
Compressive Stress ◽  
Safety Factor ◽  
Carbon Composite ◽  
The Body ◽  
Frame Structure ◽  
Structural Safety ◽  
Maximum Displacement ◽  
Electric Wheelchair ◽  
Maximum Variation

Electric wheelchairs developed so far have difficulties for elderly people to use, because of their bulkiness and heavy weight. To address this problem, this study presents a design for the construction of an electric wheelchair with an application of light duty materials at frame and a foldable structure that can be easily loaded in a narrow space. A structural analysis was performed to evaluate the structural safety of the foldable wheelchair. For the purpose of analysis, a carbon composite was used as the material for the frame; Structure Mechanics Module of COMSOL Multiphysics was used as the analysis software; and for the boundary condition, the lower part of the body frame was fixed, and a load of 150[Formula: see text]kg was applied to the upper part of the wheelchair. According to the results of the structural analysis, a maximum displacement of 2.869[Formula: see text]mm occurred at the handle where the carbon composite was applied, and tensile and compressive stress of 103[Formula: see text]MPa and 107.3[Formula: see text]MPa, respectively, were measured at the seat part of the wheelchair where the load was applied. The safety factors were 7.5 and 5.5 for tensile stress and compressive stress, respectively. A maximum variation of 0.0872[Formula: see text]mm occurred at the aluminum wheel shaft, and a maximum variation of 0.2046[Formula: see text]mm occurred at the joint. The maximum stress was 116.3[Formula: see text]MPa that corresponded to a safety factor of 2.66; this indicates that the wheelchair can be considered to be structurally safe as the safety factor exceeds the initial target of 2.

Design and Research on Aluminum-Plastic Trunk Lid

2012 ◽  
Vol 538-541 ◽  
pp. 833-840
Author(s):  
Duo Nian Yu ◽  
Li Yang Gu ◽  
Chong Yang Lu
Keyword(s):  
Design Method ◽  
The Body ◽  
Frame Structure ◽  
Light Weight ◽  
Mechanical Stiffness ◽  
Plastic Structure ◽  
Stiffness Properties ◽  
Body Design ◽  
Static Mechanical ◽  
Panel Thickness

Abstract: In this paper, the traditional trunk lid was analyzed using finite element method firstly, and then the basic mechanical properties of the lid were obtained, which were used as the topology optimization constrains of the trunk lid outer panel, then the aluminum alloy frame structure that could satisfy the static mechanical stiffness properties was designed; According to the requirement, the trunk lid inner panel was redesigned, the material properties determined in advance were given to the inner and outer panel respectively, after being assembled, the best panel thickness could be obtained by ways of size optimization. Compared to the analysis results, the new aluminum-plastic structure can meet the requirements in performance, and has significant effect on light-weight. This paper provides some reference for the development of the aluminum-plastic structure of the body design method.

Internal Force Analysis of Frame Structure Considering the Soil Constraint

2015 ◽  
Vol 777 ◽  
pp. 38-41
Author(s):  
Shu Zhi Liu
Keyword(s):  
Soil Column ◽  
Internal Force ◽  
The Body ◽  
Frame Structure ◽  
Force Analysis ◽  
Ground Floor ◽  
Calculating Method ◽  
The Earth

Part of the bottom column in the frame structure is buried in the soil,sometimes it should be considered the affects from the body of the soil when calculating the ground floor of the frame structure. The Winkler assumes is quoted in this article, as considering the coefficient of the Soil-column interaction, the equivalent height calculating formula of the column restrained by the earth is deduced , this can change the frame structure that restrained by the earth into the commonly structure to calculate. It illustrates that the restrained load by the earth in the bottom of the structure has the big affects on the internal force and lateral. It provides a simple calculating method for such structure.

scholarly journals Alternative scaffolds in radionuclide diagnosis of malignancies

2019 ◽  
Vol 18 (3) ◽  
pp. 125-133
Author(s):  
O. D. Bragina ◽  
V. I. Chernov ◽  
R. V. Zeltchan ◽  
I. G. Sinilkin ◽  
A. A. Medvedeva ◽  
...  
Keyword(s):  
High Specificity ◽  
The Body ◽  
Production Costs ◽  
Good Tolerance ◽  
New Class ◽  
The Past ◽  
Radionuclide Diagnosis ◽  
Good Penetration ◽  
Preclinical And Clinical Studies ◽  
High Immunogenicity

This review discusses a relatively new class of targeted molecules that is being actively studied for radionuclide diagnosis and treatment of malignancies. The full-size antibodies used so far have non-optimal pharmacological properties, slow distribution in the body, poor penetration into the tissue and kidney excretion, and high immunogenicity, which significantly complicates their use in clinical practice. Over the past decade, a new class of targeted molecules, called “non-immunoglobulin scaffolds” have become popular; they have all the requirements for optimal delivery of a radionuclide to tumor cells. Scaffolds usually are smaller in size in comparison with antibodies, but they are larger than peptides, and are characterized by high affinity and optimal biochemical, biophysical, biological, and economic features. The advantages of such proteins are their stable structure, good penetration into tissues, the possibility of additional functionalization and expression in the bacterial system, which ensures low production costs.The results of preclinical and clinical studies for diagnosis of malignancies using such proteins as affibody, adnectin, DARPins, etc., have demonstrated their high specificity, affinity, good tolerance and low immunogenicity. 

scholarly journals Elastoplastic bend of round steel beam. Message 2. Residual stresses

2018 ◽  
Vol 61 (11) ◽  
pp. 884-890
Author(s):  
V. N. Shinkin
Keyword(s):  
Residual Stresses ◽  
Extreme Values ◽  
General Concept ◽  
The Body ◽  
Internal Stresses ◽  
Metal Structures ◽  
Term Operation ◽  
Elastic Stresses ◽  
Deformation Hardening ◽  
Cylindrical Steel

The residual stresses in metals can lead to the defects in metals during their forming and to destruction of metal structures during their long-term operation. The resulting residual stresses during metal forming can be of plastic nature, as in the malleable metals, or caused by a slow irreversible creep at the increased temperatures and prolonged action of loads. In the viscoelastic mediums, it can be caused by the viscous parts of deformation that can accumulate when the body is deformed for a long period of time. The residual stresses also have an effect on the metals microstructure and can present inside and around the crystalline grains as the micro-residual stresses, which are called the hidden elastic stresses. Sometimes the residual stresses are called the eigenstresses by an analogy with the eigenfunctions, introduced by the mathematicians to denote the functions that correspond to the certain values (the eigenvalues) of parameters of the differential equation under the given boundary conditions. The concept of the internal stresses was proposed as a general concept for this type of stresses, created by the body itself; the term residual stresses is assigned to the case, when the internal stresses are caused by the irreversible deformation. In addition to the emergence of favorable system of residual stresses in the discs of malleable metals with a pronounced deformation hardening, there will also be a local increase in strength, provided that the Bauschinger’s effect does not negate the achieved advantages. The extreme values of residual stresses of a straight cylindrical steel rod (beam) during bending are studied below.

scholarly journals RESIDUAL STRESSES IN A THERMOELASTIC CYLINDER RESULTING FROM LAYER-BY-LAYER SURFACING

2020 ◽  
Vol 26 (3) ◽  
pp. 63-90
Author(s):  
S. A. Lychev ◽  
Montaser Fekry
Keyword(s):  
Residual Stresses ◽  
Excitation Frequency ◽  
Static Problem ◽  
The Body ◽  
Temperature Fields ◽  
Internal Stresses ◽  
Layer By Layer ◽  
Surface Residual Stresses ◽  
Different Temperatures ◽  
Uneven Heating

The article investigates the residual stresses arising in a thermoelastic cylinder as a result of layer-by-layer deposition of material on its lateral surface. Residual stresses are defined as the limiting values of internal stresses developing during the technological process. Internal stresses are caused by incompatible deformations that accumulate in the body as a result of joining parts with different temperatures. For the analysis of internal stresses, an analytical solution of the axisymmetric quasi-static problem of thermoelasticity for a layer-by-layer growing cylinder is constructed. It is shown that the distribution of residual stresses dependson the scenario of the surfacing process. In this case, the supply of additional heat to the growing body can significantly reduce the unevenness of the temperature fields and reduce the intensity of residual stresses. The most effective is uneven heating, which can be realized, for example, by the action of an alternating current with a tunable excitation frequency. This is illustrated by the calculations performed using the constructedanalytical solution.

Sign in / Sign up

Export Citation Format

Share Document