Quantum-cascade-laser- (QCL) pumped molecular lasers (QPMLs) have recently been introduced as a source of powerful ($>\phantom{\rule{-2pt}{0ex}}1$ mW) tunable THz) narrow-band ($<\phantom{\rule{-2pt}{0ex}}10$ kHz) continuous-wave terahertz radiation. The performance these depends critically on collision physics, pump saturation, and the design laser cavity. Using validated three-level mod...

Highlights • A novel numerical approach has been proposed to retrieve the hydraulic transmissivity of elliptical rock fractures in triaxial shear-flow experiments. The accuracy different methods for estimation evaluated and discussed. electrical analogy are recommended accurate evaluation fractures.

The goal of this research was to compare and evaluate the measurements taken by different instruments regarding alterations while varying ultraviolet (UV)-blocking property cladding material during its usage under real greenhouse conditions. UV-blocking covering material, low-density polyethylene (LDPE), is enriched with additives that are scattered in several layers manufacturing process, resu...

A variety of established and experimental geophysical techniques was used to measure the vertical distribution of fracture permeability in a 229-meter deep borehole penetrating schist and quartz monzonite near Mirror Lake, New Hampshire. The distribution of fractures in the borehole was determined by acoustic borehole televiewer and other geophysical logs. Fracture permeability was estimated by...

This study had as its objective the evaluation of the influence of shading screens of different colors on the different microclimate variables in a greenhouse covered with transparent low-density polyethylene (LDPE). The experiment was conducted with five treatments: thermo-reflective screen (T1); a control without screen (T2); red screen (T3); blue screen (T4); and black screen (T5), all of th...

Many geological formations consist of crystalline rock that have very low matrix permeability but allow flow through an interconnected network of fractures. Understanding the flow of groundwater through such rocks is important in considering disposal of radioactive waste in underground repositories. A specific area of interest is the conditioning of fracture transmissivities on measured values ...

The grass shrimp (Palaemonetes vuigaris) orients itself by means of the polarization pattern of the sky visible through Snell's window of the water surface. The celestial polarization pattern viewed from water is distortt.~! and modified because of refraction and repolarization of skylight at the air-water interface. This work provides a quantitative account of the repolarization of skylight tr...

Two ultrafast laser pulses at the fundamental Ti:sapphire laser wavelength of 800 nm and the second harmonic at 400 nm were used to study the temporal evolution of the transmissivity in fused silica and resulting material ablation. It was observed that there was a sharp drop in the transmissivity of the probe pulse at zero delay between the two pulses, indicating that there was enhanced absorpt...

This study investigates the feasibility of management of aquifer recharge (MAR) in Lebanon by designing well barriers to remove seawater intrusion from the fractured carbonate aquifers. Groundwater flow and saltwater/freshwater 50% sharp interface have been modeled along the coastal area using the Ghyben-Herzberg theory. The groundwater flow simulations have been supported by field transmissivi...

We present a general theory of negative refraction in periodic stratified heterostructures with an arbitrary number of homogeneous, isotropic, nonmagnetic layers in a unit cell. With a 4×4-matrix technique, we derive analytic expressions for the normal modes of such a heterostructure slab, introduce the average refraction angles of the energy flow and wavevector for the TE- and TM-polarized pla...