Technological cracks

Three processes were found to be important in considering the self sufficiency of solvent in liquefaction technology cracking of the solvent to form gases (which is < 3.6% of solvent used), condensation of solvent components, and alkylation of solvent by coal (Figure 9 ). 

A distinguishing characteristic of concrete, and in particular SPC, is a lack of soundness and equally strong bond between its structural elements. In addition, hardened concrete contains numerous micro and macro defects arising both during manufacture of the product (technological cracks) and in service (operational cracks). 

Technological cracks are often caused by sedimentation processes associated with bleeding in the concrete mix and violation of integrity and uniformity of... 

Crack formation in the manufacturing stage of SPC products and structures can be caused by stresses due to nonuniform distribution of moisture and temperature in the volume of concrete, and also as a consequence of unequal thermal expansion of SPC components during heat treatment. Loads associated with material handling, transportation, and erection can cause the formation of technological cracks. 

The mechanism of compound perforating technology crack coal... 

Slip casting and slurry coating PolycrystalUne 25-200 pm Economical Robust technology, crack formation, slow... 

Lafarie-Frenot, M.C. and Henaff-Gardin, C., Formation and Growth of 90° Ply Fatigue Cracks in Carbon/Epoxy Laminates , Composites Science and Technology Vol. 40, p. 307-324, 1991... 

J. Mattsson, Modelling of Scattering by Surface Breaking Cracks in Anisotropic Materials, Tech. Report 1996 7, Div. Mech., Chalmers University of Technology (1996). 

FlOiei Evaluation of techniques for assessing corrosion cracking In dissimilar metal welds Dr D.R. Tice AEA Technology... 

The Institute has many-year experience of investigations and developments in the field of NDT. These are, mainly, developments which allowed creation of a series of eddy current flaw detectors for various applications. The Institute has traditionally studied the physico-mechanical properties of materials, their stressed-strained state, fracture mechanics and developed on this basis the procedures and instruments which measure the properties and predict the behaviour of materials. Quite important are also developments of technologies and equipment for control of thickness and adhesion of thin protective coatings on various bases, corrosion control of underground pipelines by indirect method, acoustic emission control of hydrogen and corrosion cracking in structural materials, etc. 

Additional basic wheat products are wheat berry (kernel), bulgar, cracked wheat, wheat germ, bran, and commercial cereals. See Ref. 56 for more information on wheat science technology. 

G-9 Aromatic Petroleum Resins. Feedstocks typically used for aromatic petroleum resin synthesis boil in the approximate range of 100—300°C at atmospheric pressure, with most boiling in the 130—200°C range. The C-9 designation actually includes styrene (C-8) through C-10 hydrocarbons (eg, methylindene). Many of the polymerizable monomers identified in Table 1 for coumarone—indene type cmdes from coal tar are also present in aromatic fractions from cracked petroleum distillates. Therefore, the technology developed for the polymerization of coal-tar cmdes is also appHcable to petroleum-derived aromatic feedstocks. In addition to availabiHty, aromatic petroleum resins offer several advantages over coumarone—indene resins. These include improved color and odor, as weU as uv and thermal stabiHty (46). 

Modifiers. Latices are added to bitumens, mortars, and concrete to improve impact resistance and reduce stress cracking. Key to the use of latices in these technologies is compatibiHty between the latex and the constmction materials. 

Linear a-olefins were produced by wax cracking from about 1962 to about 1985, and were first commercially produced from ethylene in 1965. More recent developments have been the recovery of pentene and hexene from gasoline fractions (1994) and a revival of an older technology, the production of higher carbon-number olefins from fatty alcohols. 

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