Reinforcing Function of Polymer Cords Embedded in Rubber under Compression

1992 ◽  
Vol 20 (4) ◽  
pp. 254-264 ◽  
Author(s):  
X. W. Du ◽  
W. Qu ◽  
Z. M. Wan ◽  
H. Ma ◽  
M. Yao ◽  
...  

Abstract Whether polymer cords embedded in rubber under compression have a reinforcing function is still an important question in the analysis of tire structures. In this paper, on the basis of experimental results, it is confirmed that polymer cords embedded in rubber present some stiffness, thus playing a reinforcing role to a certain extent. When the cord volume fraction in the cord-rubber composite is sufficiently large, the reinforcing function of the polymer cords is so significant that the properties of the cord-rubber composite are mainly influenced by those of the cord. When the compressive stress reaches a certain value, the cord-rubber composite specimen yields by buckling if the cord volume fraction is large enough and the cord angle is within a certain small range. The buckling stress, which may be considered to be a failure stress, decreases with an increase in temperature. On the other hand, the effect of the cord angle on the buckling stress is found to be insignificant.

1948 ◽  
Vol 21 (4) ◽  
pp. 853-859
Author(s):  
R. F. A. Altman

Abstract As numerous investigators have shown, some of the nonrubber components of Hevea latex have a decided accelerating action on the process of vulcanization. A survey of the literature on this subject points to the validity of certain general facts. 1. Among the nonrubber components of latex which have been investigated, certain nitrogenous bases appear to be most important for accelerating the rate of vulcanization. 2. These nitrogen bases apparently occur partly naturally in fresh latex, and partly as the result of putrefaction, heating, and other decomposition processes. 3. The nitrogen bases naturally present in fresh latex at later stages have been identified by Altman to be trigonelline, stachhydrine, betonicine, choline, methylamine, trimethylamine, and ammonia. These bases are markedly active in vulcanization, as will be seen in the section on experimental results. 4. The nitrogenous substances formed by the decomposition processes have only partly been identified, on the one hand as tetra- and pentamethylene diamine and some amino acids, on the other hand as alkaloids, proline, diamino acids, etc. 5. It has been generally accepted that these nitrogenous substances are derived from the proteins of the latex. 6. Decomposition appears to be connected with the formation of a considerable amount of acids. 7. The production of volatile nitrogen bases as a rule accompanies the decomposition processes. These volatile products have not been identified. 8. The active nitrogen bases, either already formed or derived from complex nitrogenous substances, seem to be soluble in water but only slightly soluble in acetone.


Author(s):  
H. van Nooy

AbstractThe experimental results indicated in the present paper reveal that among all humectants admitted 1,3-butyleneglycol alone has marked fungicidal properties satisfying the requirements of practical tobacco treatment, and that, on the other hand, diethyleneglycol and glycerine practically do not have such qualities


2018 ◽  
Vol 19 (10) ◽  
pp. 3045 ◽  
Author(s):  
Takehito Kikuchi ◽  
Yusuke Kobayashi ◽  
Mika Kawai ◽  
Tetsu Mitsumata

Magnetorheological elastomers (MREs) are stimulus-responsive soft materials that consist of polymeric matrices and magnetic particles. In this study, large-strain response of MREs with 5 vol % of carbonyl iron (CI) particles is experimentally characterized for two different conditions: (1) shear deformation in a uniform magnetic field; and (2), compression in a heterogeneous uniaxial magnetic field. For condition (1), dynamic viscoelastic measurements were performed using a rheometer with a rotor disc and an electric magnet that generated a uniform magnetic field on disc-like material samples. For condition (2), on the other hand, three permanent magnets with different surface flux densities were used to generate a heterogeneous uniaxial magnetic field under cylindrical material samples. The experimental results were mathematically modeled, and the relationship between them was investigated. We also used finite-element method (FEM) software to estimate the uniaxial distributions of the magnetic field in the analyzed MREs for condition (2), and developed mathematical models to describe these phenomena. By using these practicable techniques, we established a simple macroscale model of the elastic properties of MREs under simple compression. We estimated the elastic properties of MREs in the small-strain regime (neo–Hookean model) and in the large-strain regime (Mooney–Rivlin model). The small-strain model explains the experimental results for strains under 5%. On the other hand, the large-strain model explains the experimental results for strains above 10%.


2006 ◽  
Vol 306-308 ◽  
pp. 857-862 ◽  
Author(s):  
Taisuke Sasaki ◽  
Tokuteru Uesugi ◽  
Yorinobu Takigawa ◽  
Kenji Higashi

The effect of manganese on strength and fracture toughness was investigated using five kinds of Mg-6Al-1Zn alloys. From the experimental results, the yield strength increased with increasing in manganese content until manganese content reached 0.14 wt. %. On the other hand, further increase in yield strength was not observed in case larger than 0.14 % of manganese was added. In addition, fracture toughness decreases with increasing manganese content. Fracture of magnesium alloy was ductile fracture by void coalescence. Adding excessive amount of manganese caused the increase in the presence of inclusions. This kind of particle easily became the nucleus of microvoid. As a conclusion, manganese should be added so that coarse manganese-bearing particle is not formed. Thus, 0.14 wt. % of manganese should be added to Mg-6Al-1Zn alloy in order to develop the alloy with well-balanced relationship between strength and fracture toughness.


2008 ◽  
Vol 14 (4) ◽  
pp. 307-313 ◽  
Author(s):  
F. Beltrán ◽  
A.J. Perez-López ◽  
J.M. López-Nicolás ◽  
A.A. Carbonell-Barrachina

Eight mandarin cultivars have been analyzed for their content of vitamin C, minerals (Ca, Mg, K, Na, Fe, Cu, Mn, and Zn), CIELab color coordinates (L*, a*, b*, C*, and h ab), total volatile compounds content and sensory aroma intensity of juice. Experimental results proved that no important enough differences were found in the minerals contents to decide which mandarin cultivar was of higher quality. Clemenules provided the darkest juice with the highest vitamin C content and with the most intense mandarin aroma. On the other hand, Nova and Hernandina mandarin could be considered as the worst cultivars for juice production. Finally if Clemenules mandarins were not available for juice processing, Orogrande, Clemenpons, Ellendale, and Marisol could also be good options.


Sensors ◽  
2019 ◽  
Vol 19 (2) ◽  
pp. 352 ◽  
Author(s):  
Kairui Cao ◽  
Rui Li

Hysteresis is a kind of nonlinearity with memory, which is usually unwanted in practice. Many phenomenological models have been proposed to describe the observed hysteresis. For instance, the Prandtl-Ishlinskii (PI) model, which consists of several backlash operators, is the most widely used. On the other hand, the well-known Madelung’s rules are always used to validate hysteresis models. It is worth pointing out that the PI model obeys Madelung’s rules. In this paper, instead of considering these rules as criteria, we propose a modeling method for symmetric hysteresis by directly constructing the trajectory based on Madelung’s rules. In the proposed method, turning points are recorded and wiped out according to the input value. After the implementation of the recording and wiping-out mechanisms, the curve which the current trajectory moves along can be determined and then the trajectory can be described. Furthermore, the relationship between the proposed method and the PI model is also investigated. The effectiveness of the presented method is validated by simulation and experimental results.


2007 ◽  
Vol 280-283 ◽  
pp. 1041-1044
Author(s):  
Yong Huang ◽  
Li Ming Zhang ◽  
Hai Feng Li ◽  
Tian Ma

The effects of solid volume fraction (SVF) on the gelation of alumina suspensions for gelcasting, debonding and sintering of the green body were studied. It was found that with SVF rising, the gelation of alumina suspension delayed; and the strength of green body decreased. On the other hand, high SVF resulted in that polymerized acrylamide split at a relative low temperature. These phenomena manifest that the fast polymerization of monomers in high SVF alumina suspension was inhibited, and the flexibility of the gelcasting was improved. However, Excessive solid volume fraction was prone to a bad rheological behavior of alumina suspension, and deteriorated the microstructure and properties of sintered body.


1964 ◽  
Vol 19 (6) ◽  
pp. 747-755
Author(s):  
W. J. De Wet ◽  
J. Los

The design of mass diffusion columns operated with partition membranes, for the separation of light gaseous isotopes, is discussed. A theoretical analysis of experimental results obtained indicates that a good agreement between experimental results and theory is only obtained at low column pressures and moderate countercurrent flow rates. At fairly low countercurrent flow rates mixing effects due to viscous dragging and gas solubility by the condensate appear to be considerable whereas excessively high countercurrent flow rates, on the other hand, also seem undesirable. Some suggestions are proposed to obviate impairing effects at least to some extent.


Algorithms ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 14
Author(s):  
Jianjian Ji ◽  
Gang Yang

Existing image completion methods are mostly based on missing regions that are small or located in the middle of the images. When regions to be completed are large or near the edge of the images, due to the lack of context information, the completion results tend to be blurred or distorted, and there will be a large blank area in the final results. In addition, the unstable training of the generative adversarial network is also prone to cause pseudo-color in the completion results. Aiming at the two above-mentioned problems, a method of image completion with large or edge-missing areas is proposed; also, the network structures have been improved. On the one hand, it overcomes the problem of lacking context information, which thereby ensures the reality of generated texture details; on the other hand, it suppresses the generation of pseudo-color, which guarantees the consistency of the whole image both in vision and content. The experimental results show that the proposed method achieves better completion results in completing large or edge-missing areas.


2009 ◽  
Vol 635 ◽  
pp. 49-54 ◽  
Author(s):  
Tomoyuki Kakeshita ◽  
Takashi Fukuda ◽  
Tomoyuki Terai ◽  
Toyotaka Osakabe ◽  
Kazuhisa Kakurai

We have investigated stress and temperature dependences of the structure of the X-phase in Ni2MnGa to understand structural relation between the X-phase and other phases. Position and intensity of satellites of the X-phase are different from those of the intermediate (I-) phase under compressive stress, but they approach those of the I-phase with decreasing stress. That is, the structure change associated with the I → X transformation is discontinuous under a compressive stress, while it is continuous under zero stress. In addition, the transformation from the X-phase to the L21-type parent phase is continuous regardless of applied stress. These results strongly suggest the existence of multi-critical point in Ni2MnGa. On the other hand, the transformation from the X-phase to the martensite phase is discontinuous regardless of applied stress.


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