Studies on Spectrophotometry. Vll.

The effects of water content on diffuse reflectance spectrophotometry studies of deep-sea sediment cores

Sediment cores recovered during ODP drilling operations are commonly scanned using a Minolta CM-2002 spectrophotometer to obtain spectral data. Core processing procedures aboard the JOIDES Resolution require that these spectral data be measured on wet cores. However, the effects of changing water content on the spectra of marine sediments is unknown. We examined the effects of changing water co...

Offering Scalable Layer 2 Services with VPLS and VLL Introduction

Over the last few years, there has been an increasing interest in deploying scalable, end-toend Layer 2 services. Several developments in the area of Layer 2 VPNs have helped to convert this into reality. Chief among these are two MPLSbased technologies, Virtual Private LAN Service (VPLS) and Virtual Leased Line (VLL) that offer the power of delivering scalable multi-point and point-to-point se...

Offering Scalable Layer 2 Services with VPLS and VLL

Fluorescence Spectrophotometry

Fluorescence and phosphorescence are photon emission processes that occur during molecular relaxation from electronic excited states. These photonic processes involve transitions between electronic and vibrational states of polyatomic fluorescent molecules (fluorophores). The Jablonski diagram (Figure 1) offers a convenient representation of the excited state structure and the relevant transiti...

Low-temperature spectrophotometry

Photoreactions of the fourth rhodopsin-like pigment, phoborhodopsin (pR480), of Hulobacrerium halobium were studied by low-temperature spectrophotometry. Upon irradiation of pR480 at -80 as well as 170°C with 436 nm light, a new intermediate having a difference absorption maximum at about 520 nm was produced. We designate this intermediate ‘P520’. Prolonged irradiation caused the formation of a...