Stitch diameter

The big diameter LK was first introduced in the year 2000 by Vajpayee [50] for a use in the surgical treatment of sequelae due to comeal bums. Vajpayee has recorded the results of nine ocular operations. The intervention begins with a conjunctival peritectomy over 360°. The conjunctiva is reclined backwards. The recipient cornea is trepanned to a 12-13 mm diameter and to a 300 pm depth. The lamellar graft is sampled via a trepanation at 1.5 mm back to the limbus in order to include LSC. It is then sutured by 24 10/0 nylon stitches. Despite the limbus allograft, no immunosuppressive therapy has been prescribed. The operation was practiced about 30 months after the occurrence of the bum. Results are recorded after a 7.4 month observation. The visual acuity has improved in six cases. No recurrence of the comeal neovascularization and no... 

The stitches or eyelets should not be so close together that there is risk that the pieces might tear. For similar reasons, tension and strain on the join should be avoided. The fixing (clips, eyelets, thread, etc.) should be compatible with the articles to be joined, not harder or more abrasive. Film, non-woven, and woven fabrics all may be finished in this way. With film and non-wovens the stitches should be loose and separated fairly widely thread should be of about the same diameter as the thickness of film or fabric. When selecting thread or other fixings for woven fabrics the gauges should be compatible with the warp and weft (not too thick, and not too fine). 

During stitching, the needle along with the thread enters the space between two consecutive picks (yams perpendicular to the seam). The extent of deformation of the weft yams will take place depending on the spacing between these two picks and the diameter of the sewing thread. 

When a tensile load is applied to a fabric seam, it has to overcome two types of frictional forces. One is the inter-yam frictional forces within a fabric, and the other is the frictional force of the stitch assembly. The former is dependent upon the crimp, yam diameter, fiber content, and number of cross-over points. The latter, however, is dependent upon the fabric properties like fiber content, type of yam (spun or filament), thickness, lateral compression, cover factor (threads per cm), bending, shear, tensile and surface roughness, and coefficient of friction. It is also dependent upon the properties of the sewing thread like fiber content, diameter, coefficiait of Mction, initial modulus, and extensibility. All of these properties, together with the machine variables like needle and bobbin thread tension and the stitch length, make up the frictional force of the stitch assembly. Thus different combinations of these would be expected to provide different frictional resistance and hence different loads at which seam slippage may take place. 

The key feature of circular weft knitting is to produce fabric structures in a tubular form. Figure 6.5 shows a tubular weft-knitted fabric developed for vascular stent application on a circular weft knitting machine with a small-diameter cylinder. The diameter and stitch density of a tube can be adjusted by varying the cylinder diameter and machine gauge, respectively. 

In 2007 Seim et al. presented a new flexible light diffuser based on embroidered optical fibres [12,15]. The latter was composed of a dense woven stmcture (100% polyester multifilament with a textile finish, a weight of 50g/m and a density of 29 threads/cm in warp and weft) in which plastic optical fibres (diameter of 175 pm) were fixed with a 100% polyester twisted staple fibre yam. The authors specified that the fibres form an average of 28 random loops per squared centimetre (loop diameter of about several hundreds of micrometres) and that a minimum stitch-to-stitch distance of 1 mm was achieved. The whole flexible diffuser is about 2 mm height and 11 cm of active area a picture of it is presented in Fig. 4.13. 

As exemplified by the above case, the HBC nanotubes become totally insoluble after surface polymerization. Hence, reversible polymerization on the nanotube surface is interesting for lithographic patterning. For the realization of this possibility, HBC 4 appended with thiol groups was designed (Figure 1), which can be stitched at the tubularly assembled state by oxidative surface polymerization. The acetyl-protected version of thiol-appended HBC 4 self-assembles in THF to form nanotubes with a diameter of... 

A latest example features coordination chemistry for supramolecular stitching of HBC nanotubes." By means of vapor diffusion, HBC 6 with pyridine (Py)-appended TEG side chains (Figure 1) is self-assembled properly into nanotubes with a diameter of 18nm (Figure 9a and e). On the other hand, when 6 is allowed to coassemble under heat-cool conditions with fran -[Pt(PhCN)2Cl2] in toluene, a poor solvent for 6, a nanotubular object with a diameter of 28 nm forms (Figure 9b and f) ... 

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