Mechanical production of metamorphic banding—a critical appraisal

1974 ◽  
Vol 111 (4) ◽  
pp. 287-292 ◽  
Author(s):  
D. Shelley
Keyword(s):  
Laminar Flow ◽  
Critical Appraisal ◽  
Particle Interaction ◽  
Interaction Effects ◽  
Metamorphic Rocks ◽  
Mechanical Process

SummaryThe mechanical process for producing foliation (banding) in metamorphic rocks, as proposed by Schmidt (1932), is shown to be inadequate. Examples in the literature ascribed to the mechanism are insufficiently supported and the metallurgical analogy for the process is found to be false. A possible restatement of a mechanical process by analogy with particle interaction effects during the laminar flow of suspensions is discussed. Evidence from metamorphic rocks indicates, however, that the modified mechanical process cannot be responsible for common metamorphic layering.

Effect of the Short Fiber on the NR Composite and the NR-SBR Composite

2012 ◽  
Vol 581-582 ◽  
pp. 552-555
Author(s):  
Cai Jun Liu
Keyword(s):  
Mechanical Properties ◽  
Energy Consumption ◽  
Short Fiber ◽  
Maximum Power ◽  
Mechanical Process ◽  
Contrast Method ◽  
Unit Energy ◽  
Unit Energy Consumption

The influence of the pretreatment polyester short fiber on the mechanical process and the properties of the NR/ SBR compound was studied by using contrast method. The results showed that the maximum power and the unit energy consumption increased because of short fiber, and the temperature also enhanced. So the low rotate speed is better. When the composite were cured, it had much characteristic such as rapid vulcanization speed, short scorch time and vulcanization smooth period. But the mechanical properties were increased. In the end, the microscopic photo of composite with the scanning electronic micrograph was taken.

Textures Applied to Mechanical Processing Technology Assessment in Ancient Bronze

2005 ◽  
Vol 495-497 ◽  
pp. 719-724
Author(s):  
R.E. Bolmaro ◽  
B. Molinas ◽  
E. Sentimenti ◽  
A.L. Fourty
Keyword(s):  
Orientation Distribution ◽  
Distribution Functions ◽  
Archaeological Sites ◽  
Mechanical Processing ◽  
Post Processing ◽  
X Ray Diffraction ◽  
Mechanical Process ◽  
X Ray ◽  
Pole Figures ◽  
Microscopic Inspection

Some ancient metallic art craft, utensils, silverware and weapons are externally undistinguishable from modern ones. Not only the general aspect and shape but also some uses have not changed through the ages. Moreover, when just some small pieces can be recovered from archaeological sites, the samples can not easily be ascribed to any known use and consequently identified. It is clear that mechanical processing has changed along history but frequently only a "microscopic" inspection can distinguish among different techniques. Some bronze samples have been collected from the Quarto d’Altino (Veneto) archaeological area in Italy (paleovenetian culture) and some model samples have been prepared by a modern artisan. The sample textures have been measured by X-ray Diffraction techniques. (111), (200) and (220) pole figures were used to calculate Orientation Distribution Functions and further recalculate pole figures and inverse pole figures. The results were compared with modern forging technology results. Textures are able to discern between hammering ancient techniques for sheet production and modern industrial rolling procedures. However, as it is demonstrated in the present work, forgery becomes difficult to detect if the goldsmith, properly warned, proceeds to erase the texture history with some hammering post-processing. The results of this contribution can offer to the archaeologists the opportunity to take into consideration the texture techniques in order to discuss the origin (culture) of the pieces and the characteristic mechanical process developed by the ancient artisan. Texture can also help the experts when discussing the originality of a certain piece keeping however in mind the cautions indicated in this publication.

5. Notice of the Ravages of the Limnoria Terebrans on Creosoted Timber

1862 ◽  
Vol 4 ◽  
pp. 612-616
Author(s):  
David Stevenson
Keyword(s):  
Civil Engineer ◽  
British Museum ◽  
Timber Structures ◽  
Mechanical Process ◽  
Interesting Species

The author stated that it would be difficult to estimate the value of any chemical or mechanical process whereby timber might be rendered permanently impervious to the ravages of the Limnoria terebrans, that small but sure destroyer of timber structures exposed to the action of the sea.The ravages of that crustacean were first observed in 1810 by Mr Robert Stevenson, the engineer of the Bell Rock Lighthouse, in the timber supports of the temporary beacon used by him in the erection of that work. Having forwarded specimens of the insect, and of the timber it had destroyed, to Dr Leach, the eminent Naturalist of the British Museum, Dr Leach, in 1811, announced it as a “new and highly interesting species which had been sent to him by his friend Robert Stevenson, civil engineer,” and assigned to it the name of Limnoria terebrans (Linnean Trans., vol. xi. p. 370, and Edinburgh Encyclopædia, vol. vii. p. 433).

Fabrication of Ultrathin Bragg Beam Splitter by Plasma Chemical Vaporization Machining

2012 ◽  
Vol 523-524 ◽  
pp. 40-45 ◽  
Author(s):  
Taito Osaka ◽  
Makina Yabashi ◽  
Yasuhisa Sano ◽  
Kensuke Tono ◽  
Yuichi Inubushi ◽  
...  
Keyword(s):  
Beam Splitter ◽  
Bragg Reflection ◽  
Free Electron Lasers ◽  
Crystalline Perfection ◽  
Plasma Chemical ◽  
High Quality ◽  
Rocking Curve ◽  
Mechanical Process ◽  
X Ray ◽  
Beam Splitters

A novel fabrication process was proposed to produce high-quality Bragg beam splitters for hard X-ray free-electron lasers (XFELs), which should consist of thin, bend-free, and robust Bragg-case crystals without any defects. A combination of a mechanical process and plasma chemical vaporization machining was employed. High crystalline perfection of the fabricated Si(110) crystal was verified with X-ray topography and rocking curve measurements. In addition, the thickness was evaluated to be 4.4 μm from the fringe period of the measured rocking curve. The crystal can be employed in Bragg beam splitters using the (220) Bragg reflection for X-ray pump-X-ray probe experiments with XFEL sources.

Optimization for Spindle of Jade Carving Machine Based on Fuzzy Reliability Theory

2010 ◽  
Vol 37-38 ◽  
pp. 801-805
Author(s):  
Huai Rong Shi ◽  
Yan Nian Rui
Keyword(s):  
Reliability Theory ◽  
Fuzzy Reliability ◽  
Design Quality ◽  
Combined Model ◽  
Mechanical Process ◽  
Fuzzy Variables ◽  
Mechanical Products ◽  
Machine Spindle ◽  
Full Consideration

In machines working under the effect of alternating stresses, the fatigue bending deflection occured occasionally. On the basis of the Fuzzy Reliability Theory and with full consideration of the fuzzy factors during mechanical process, the paper studied the fuzzy reliability optimal design for the hollow spindle of multi-functional jade carving machine and improved the design quality of the jade carving machine spindle by probing into the combined model constructed by the random variables and fuzzy variables. The design was approved to be advanced, reliable and practical in service and provided a new way for the design of multifunctional jade carving machine spindle and other mechanical products.

Amorphization of Atorvastatin Calcium by Mechanical Process: Characterization and Stabilization Within Polymeric Matrix

2017 ◽  
Vol 12 (3) ◽  
pp. 216-225 ◽  
Author(s):  
Malek Lemsi ◽  
Haykel Galai ◽  
Mohamed Radhouan Louhaichi ◽  
Hatem Fessi ◽  
Rafik Kalfat
Keyword(s):  
Polymeric Matrix ◽  
Mechanical Process ◽  
Atorvastatin Calcium ◽  
Process Characterization

Material Removal and Application by Chemical Impact Reaction in Nano-Abrasive Jet Polishing

2013 ◽  
Vol 631-632 ◽  
pp. 550-555
Author(s):  
Wen Qiang Peng ◽  
Sheng Yi Li ◽  
Chao Liang Guan ◽  
Xin Min Shen
Keyword(s):  
Material Removal ◽  
Abrasive Particle ◽  
Precision Machining ◽  
Optical Surface ◽  
Polishing Process ◽  
Abrasive Particles ◽  
Mechanical Process ◽  
Abrasive Jet Polishing ◽  
Ultra Precision ◽  
Machining Properties

Material removed by mechanical process inevitably causes surface or subsurface damage containing cracks, plastic scratch, residual stress or dislocations. In nano-abrasive jet polishing (NAJP) the material is removed by chemical impact reaction. The chemical impact reaction is validated by contrast experiment with traditional lap polishing process in which the material is mainly removed through mechanical process. Experiment results show the dependence of the abrasive particles on the choice of materials. Even if the abrasive particle and the workpiece are composed of similar components, the machining properties are remarkably different due to slight differences in their physical properties or crystallography etc. Plastic scratches on the sample which was polished by the traditional mechanical process are completely removed by NAJP process, and the surface root-square-mean roughness has decreased from 1.403nm to 0.611nm. The NAJP process will become a promising method for ultra precision machining method for ultrasmooth optical surface.

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