scholarly journals Observations on the blood-corpuscles, particularly with reference to opinions expressed and conclusions drawn in papers ‘on the corpuscles of the blood,’ and ‘on fibre,’ recently published in the Philosophical Transactions

The author points out what he considers to be important errors in the series of papers by Dr. Martin Barry, which have lately appeared in the Philosophical Transactions, and are entitled, “ On the Corpuscles of the Blood ," and “ On Fibre ." He alleges that Dr. Barry has generally confounded the colourless corpuscles contained in the blood with the red corpuscles of the same fluid; each of which latter kind consists of a vesicle or cell, with thick walls, but in a collapsed and flattened state, and having therefore a biconcave form, and in consequence of its thick wall being doubled on itself, presenting under the microscope a broad circumferential ring, which is illuminated or shaded differently from the depressed central portion, according to the focal adjustment of the instrument: while the colourless corpuscles, on the other hand, are of a globular shape, strongly refractive of light, and granulated on their surface, and are of less specific gravity and of somewhat larger size than the red corpuscles. The author quotes various passages from Dr. Barry’s papers in proof of his assertions, and refers particularly to fig. 23 of his second paper on the corpuscles of the blood. He farther states, that Dr. Barry’s description of the appearances of what he terms the red corpuscles, in paragraphs 53, 68, and 76 of his second paper, can, in fact, apply only to the colourless corpuscles: and he observes, that even when Dr. Barry does, at last, in his “Additional Observations,” advert to the distinction between the red and the colourless globules, he considers the latter as being merely “the discs” contained in the red globules appearing under an altered state. The author regards as wholly erroneous the notion which Dr. Barry entertains that a fibre exists in the interior of the blood-cor­puscle; and that these fibres, after their escape from thence, constitute the fibres which are formed by the consolidation of the fibrin of the liquor sanguinis . The beaded aspect presented by the double contour of the thick wall of the red corpuscle when it has been acted upon either by mechanical causes or by chemical reagents, of which the effect is to corrugate the edge, and to bend it alternately in opposite directions, has, in the opinion of the author, given rise to the illusive appearance of an internal, annular fibre. The appearance of flask-like vesicles presented by some of the red corpuscles, with the alleged fibre protruding from their neck, the author ascribes altogether to the effects of decomposition, which has altered the mechanical properties of the corpuscle, and allowed it to be drawn out, like any other viscid matter, into a thread.

e-Polymers ◽  
2003 ◽  
Vol 3 (1) ◽  
Author(s):  
Koh-hei Nitta ◽  
Yoshikazu Yamamoto

Abstract We examined mechanical and morphological properties of fully transcrystalline polypropylene grown from the surface of poly(tetrafluoroethylene) sheets. Comparison of mechanical properties between transcrystalline and spherulitic polypropylenes demonstrated that Young’s modulus is dependent on the crystallinity and independent of the supermolecular structure. On the other hand, the mechanical yielding process was predominantly affected by the supermolecular structure, and the mechanical energy required for yielding of transcrystalline sheets was greater than that of the spherulitic morphology. In addition, it was found that mechanical necking is required for the alignment of lamellae in the stretching direction. This means that the unfolding process of lamellae orienting in the stretching direction is associated with necking and ductility.


1931 ◽  
Vol 4 (1) ◽  
pp. 54-63
Author(s):  
H. Mark ◽  
E. Valko

Abstract It is only during recent years that it has become possible by the use of new technic to detect molecular phenomena produced in the mechanical deformation of substances. As far as metallic substances are concerned, and crystalline substances in particular, the problem has already been solved for the most part. On the other hand, in spite of considerable progress during recent years the study of the deformation of organic substances and of fibers in particular, in which group rubber is included, has not yet been carried on. The mechanical properties of a crystalline system vary according to whether there is a single crystal or an aggregate of crystals. However, in both cases the extensibility of the products originates in a displacement of parallel layers, i. e., a sliding of the parts of the crystal along definite crystalline planes, this phenomenon of sliding being irreversible in these substances. In fact, in these cases the reversible part of the elongation is very weak, and amounts to only a few thousandths of the entire phenomenon. In brief, the phenomena of hardening brought about by deformation (sometimes observable) are due to disturbances of the regular lattice. In particular, the displacement of the atom and the change from its normal position can cause the appearance of irregularities on the surface of sliding.


2014 ◽  
Vol 699 ◽  
pp. 169-174
Author(s):  
Achmad Zubaydi ◽  
Nurul Muhayat ◽  
Budie Santosa ◽  
Dony Setyawan

Double sided friction stir butt welds on 6 mm thick of 5083 aluminum alloy were produced. Two variants of the weld side combination, different weld side (DS) and same weld side (SS), have been made to investigate the effect of the weld side on mechanical properties.The SS is a double sided welding process that produces advancing side in one plate and retreating side in the other one. On the other hand, the DS is a double sided welding process that causes advancing side and retreating side in each plate. Tensile properties of the joints were evaluated and correlated with macrostructure and hardness. The weld side influenced the macrostructure and mechanical properties of welded joints. The different weld side (DS) had better mechanical properties than the same weld side (SS).


2015 ◽  
Vol 815 ◽  
pp. 164-169
Author(s):  
Ng Hooi Jun ◽  
Mohd Mustafa Al Bakri Abdullah ◽  
Kamarudin Husin ◽  
Soo Jin Tan ◽  
Mohd Firdaus Omar

Utilization and suitability of bottom ash in Portland cement have been increasing significantly in recent year. Bottom ash has substantial effects on mechanical properties with different composition of replacement in mixture of bottom ash and Portland cement. Bottom ash was used to determine the feasibility of the substitution as recycling product from industry depending on the percentage of the bottom ash. On the other hand, bottom ash offers a better solution for maintaining materials characteristic of Portland cement mortar and also provide beneficial mechanical performance. The result of using bottom ash in Portland cement mortar showed that it could make better the mechanical properties and hence disposed bottom ash wastes safely in technical, economic and environmental methods.


2018 ◽  
Vol 56 (2A) ◽  
pp. 63-68
Author(s):  
Le Thi Bang

Bis-3,4- dimethyldibenzylidene sorbitol (DMDBS); bis-p-methylbenzylidene sorbitol (MDBS) and the mixture of DMDBS/MDBS (50/50) were studied through optical, thermal, mechanical properties and surface morphology. With the same amount of additive (DMDBS/MDBS mixture and DMDBS) in the material, the results are similar. On the other hand, using an additive mix reduces the cost of production due to MDBS. Furthermore, the additive mixture is used without producing odours. Therefore, the mixture of DMDBS/MDBS (50/50) is chosen.


2011 ◽  
Vol 250-253 ◽  
pp. 480-484 ◽  
Author(s):  
Miao Zhou Huang ◽  
Tao Meng ◽  
Xiao Qian Qian ◽  
Jin Jian Zhang

The flow ability, mechanical properties and microstructure of concrete with different strength grades affected by nano-SiO2and nano-CaCO3was studied. The experiment results showed that the strength of concrete at early age was increased by adding the nano-materials if the strength grade of concrete was not high. But the strength at the age of 28 days was not affected a lot by adding these nano-materials. On the other hand, it was not useful to the strength if the strength grade of concrete was high.


2008 ◽  
Vol 584-586 ◽  
pp. 547-552 ◽  
Author(s):  
Daisuke Terada ◽  
Toshiaki Masui ◽  
Naoya Kamikawa ◽  
Nobuhiro Tsuji

Effect of solid solution elements on microstructure evolution and mechanical properties was investigated using a high purity Al (purity 99.99%) and Al-0.5 at.% X ( X = Si, Ag, Mg ) alloys deformed by accumulative roll bonding (ARB) process up to 7 cycles (equivalent strain of 5.6) at ambient temperature. The ARB-processed high purity Al showed the equiaxed microstructure having mean grain size of 750 nm. On the other hand, the microstructure of the ARB-processed Al-0.5at.%X alloys showed lamellar boundary structures elongated along RD. The mean lamellar boundary spacing significantly differed depending on the alloying elements, which suggested that solute atoms had a significant effect on microstructure evolution. The difference in the grain size was regarded to be caused by the difference in recovery processes in the alloys. The tensile strength of the alloys increased with increasing the number of ARB cycles. In the Al-Si and Al-Ag alloys, the post-uniform elongation increased with increasing the number of the ARB cycles. On the other hand, the elongation of the Al-Mg hardly changed during the ARB process.


1937 ◽  
Vol 10 (3) ◽  
pp. 556-563
Author(s):  
Shohei Saito ◽  
Katsumi Ishiguro

Abstract Experiments were carried out to determine the resistance of rubber products to vibration. There were no essential changes in mechanical properties as a result of vibration for 50 to 100 hours. There were on the other hand considerable changes in electrical properties, e. g., the insulation resistance decreased with increase in time of vibration. Further experiments in connection with this problem will be carried out to obtain data on the effects of vibration for prolonged periods. The authors wish to thank Messrs. Endo, Taguma, Hamono, and Wada for their aid in the experimentation.


Author(s):  
Fyaçal Baira ◽  
Mosbah Zidani ◽  
Hichem Farh ◽  
Salim Messaoudi ◽  
Toufik Ziar ◽  
...  

Copper destined for electrical cabling require a compromise of mechanical properties and electrical resistivity. The drawing process accompanied by the formation of crystalline defects, such as gaps and dislocations, which leads to the increase in hardness, and therefore to the increase in resistivity, a very important characteristic for the conductivity and the efficiency of the cable. The scope of this work is to investigate the phenomenon of deformation texture evolution while copper wire drawn destined for electric cable-making and to understand its relationship with the electrical conductivity. In this study, we notice that the hardness and the resistivity increase with an increase of the deformation level. On the other hand, a slight decrease in the resistivity of the wires was observed after a holding time of 30 min at 260°C. The annealing of wires at 260°C for 9 min of holding time leads to a recrystallisation especially for high deformations and a gradual return of the mechanical properties and of the microstructure towards a state close to the state of the wire rod with the extension of time . The recrystallization texture is composed of the same components as the drawing texture, fibers <111>//ND (Normal Direction) and <001>//ND. The decrease in the intensity of the fiber after annealing is observed. On the other hand, the fiber <001> // ND remains stable.


2009 ◽  
Vol 610-613 ◽  
pp. 155-160
Author(s):  
Jian Hua Wan ◽  
Heng Hu Sun ◽  
Ying Ying Wang ◽  
Chao Li

The effect of the thermal treated red mud on mechanical properties of loess –containing aluminosilicate based cementitious materials is investigated. And the characteristic of hydration production is tested using XRD, SEM and EDAX methods. The results show that the thermal treated red mud not only has excellent cementitious properties but also can improve the mechanical properties of loess –containing aluminosilicate based cementitious materials. Moreover when the content of red mud is 5%, the improved effect is optimal. On the one hand, the alkaline ingredients of red mud can promote abundant ettringites to produce at early ages. And the ettringites contribute to early strength of the cementitious material. On the other hand, the content of red mud is too high to improve the long-term strength.


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