This book contains information about the technological development of ion exchange in their application for industrial processes. Widely used and well known fields of ion exchange like chromatography and electromembrane technology are described in this book with experimental details. Designing new materials for nanotechnology and nanomaterials as ion exchanger are also explained by experimental proofs. Ion exchange book is suitable not only for postgraduate students but also for researchers in chemistry, biochemistry and chemical technology....
Although cataract surgery has been performed
for many centuries, technological advances now
provide us with the opportunity to afford our
patients vision more similar to the pre-cataract
state than ever before. Advanced instrumentation
and surgical techniques allow our patients to
expect excellent uncorrected vision within 24 h
of surgery. In addition, newer multifocal and
accommodating intraocular lens (IOLs) offer the possibility of distance, near, and intermediate
vision without glasses [2, 23, 32]....
An optical fiber is a cylindrical dielectric waveguide made of low-loss materials such as silica glass. It has a central core in which the light is guided, embedded in an outer cladding of slightly lower refractive index (Fig. 8.0-l). Light rays incident on the core-cladding boundary at
Fiber optic connectors are produced by polishing their endfaces to create a smooth domed shape.
If the shape or endface geometry is precisely controlled, the result will be physical contact between
fiber cores when two connectors are mated together. The polishing process creates a very small
damaged layer at the tip of the fiber that has a higher index of refraction (index layer) than the
glass before the damaged layer.
Visual Acuity The Snellen chart is used to test acuity at a distance of 6 m (20 ft). For convenience, a scale version of the Snellen chart, called the Rosenbaum card, is held at 36 cm (14 in) from the patient (Fig. 29-1). All subjects should be able to read the 6/6 m (20/20 ft) line with each eye using their refractive correction, if any. Patients who need reading glasses because of presbyopia must wear them for accurate testing with the Rosenbaum card. If 6/6 (20/20) acuity is not present in each eye, the deficiency in vision must be...
Dermoscopy, also called dermatoscopy, epiluminescence microscopy or skin surface
microscopy, was developed in the 1990s in order to augment the early diagnosis of
melanoma. First technologies allowed the observer to examine pigmented skin lesions
covered by a drop of oil and a glass slide through a stereo microscope. Then dermoscopy
developed into a hand-held lighted magnifier to analyze skin lesions by observing newly
defined and descriptively named subsurface structures: eg, dots, streaks, veils, and