Selective layer delamination

Figure I represents a two-dimensional damage distribution of an impact in a 0/90° CFRP laminate of 3 mm thickness. Unlike in ultrasonic testing, which is usually the standard method for this problem, there is no shadowing effect on the successive layers by delamination echos. With the method of X-ray refraction the exact concentration of debonded fibers can be calculated for each position averaged over the wall thickness. Additionally the refraction allows the selection of the fiber orientation. The presented X-ray refraction topograph detects selectively debonded fibers of the 90° direction.

A delaminated zeolite with an Si/Al ratio of 29, derived from the layered zeolite Nu-6(1), was employed as catalyst for dehydration of xylose at 170 °C, using a water-toluene biphasic reactor-system.140 This material, designated del-Nu-6(l), proved to be efficient for this transformation, giving 47% selectivity to furfural at 90% xylose conversion. 

The industrial partner was able to produce several adhesive layers with the required mechanical properties. There was a need to select a limited number of the adhesive layers for ftrrther tests. The selection was done based on creep and delamination tests. 

Alumina-pillared synthetic boron-containing s qx)nite was prepared for the first time. The introduction of boron into the S2qx)nite layers markedly enhanced both cumene dealkylation activity and benzene selectivity of its pillared product The pillared product of synthetic boron-containing saponite was pillared clay rather than delaminated clay. 

Fig. 17.24 TEM micrographs of nylon 6/organoclay/EOR-g-MA (76/4/20) ternary nanocomposite showing (a) submicron and nano-voids which are associated with intra-gallery delamination of some organoclay layers (note that the section is not selectively stained in order to clearly reveal delaminations of clay layers), (b) cavitation of EOR-g-MA particles which preferentially starts from the larger particles as indicated by arrows, and (c) extensive matrix shear yielding at the arrested crack tip which in turn causes the EOR-g-MA particles and delaminated clay layers to collapse within the matrix. A schematic of the arrested crack tip illustrating different locations from where TEM micrographs (a-c) were taken is also shown. Note that the schematic is not to scale (Lim et al. 2010)...

In attempts already made in the early 1970s, the ion-selective polymeric membrane was directly applied to a metal wire. From a theoretical point of view, this is an unsatisfactory situation because in all but a few exceptions these membranes contain neither a redox-active cation of the metal of which the wire is made nor an electron acceptor/donor pair that determines the redox potential. As a result, the phase boundary potential at the membrane/metal interface of most coated-wire ISEs is poorly defined. It is still not well understood why in real life freshly prepared coated-wire electrodes sometimes perform surprisingly well under circumstances when they can be recalibrated relatively frequently. However, formation of a water layer at the metal-membrane interface leads eventually to memory effects and, after delamination of the sensitive membrane, to catastrophic failure. 

In the manufacture of rubber expansion joints, material selection and formulation should be considered against the constructional characteristics required in the product. Rubbers, compounds, adhesives and solvents are all thoroughly checked for quality, to avoid possible layer separation or delamination of the layers while the joints are being built. 

Underfill Material Selection. The underfill material selected in flip chip BGA (FCBGA) packages could significantly impact the reUabiUty of the board mounted package. If the underfill material is too stiff, it would rigidize the assembly and thus transfer more strain to the silicon die. This could result in delamination at any of the critical interfaces underfill/ passivation, passivation/die, underfill/substrate, or within low-A layers. 

Figure 14.17 shows the effect of the phosphonate monolayer (self-assembled N-ethylamino-phosphonate, NEAP) on the delamination of an amine-modified epoxide ester from Fe-6.3A1-alloy surfaces. This ester is a basis for a number of industrial primers. As can be seen, the just pol5uner-coated alloy is delaminated quite rapidly. Delamination is much slower if the alloy is thermally treated in such a way that a thin insulating layer is formed by selective oxidation, and thus oxygen reduction is inhibited. If an additional phosphonate layer is built into the interface, the delamination is also significantly slowed down [116]. 

Hierarchical micro/mesopore structure can be obtained by forming composite from delaminated layered-stmcture zeohte and a mesoporous MTS material. At the same space time the bifunctional zeolite catalyst, having hierarchical micro/mesoporous stractme, show lower n-C hydroconversion activity and higher hydroisomerization selectivity than the corresponding microporous zeolite catalyst. 

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