ABSTRACT
We present both experimental and numerical data showing the absorption of unpolarized, normally incident light by a gold crossed grating having a shallow sinusoidal profile. We show furthermore that the total absorption of unpolarized light can be achieved for an angle of incidence of 30 degrees with a crossed grating having its period adjusted appropriately from the normal incidence case to preserve the plasmonic resonance responsible for the enhanced absorptance. We contrast the process for achieving high absorptance in the principal plane of incidence aligned with the grooves of one of the gratings, with that for the principal plane at 45 degrees to each grating.
Subject(s)
Light , Absorption , Metals/chemistry , Spectrum AnalysisABSTRACT
Sodium, potassium, and chloride were determined in fetal and maternal plasma of six cows between 208 and 269 days of gestation. Blood pH and partial pressures of oxygen and carbon dioxide also were measured in samples collected from the jugular vein of the cow and the caudal aorta and vena cava of the fetus. Concentration of chloride in fetal plasma was generally lower than the corresponding maternal value, and fetal potassium was greater than maternal. Potassium of fetal plasma increased towards term. Sodium concentrations were not significantly different between fetal and maternal plasms. Once fetal and maternal pH and blood gas tensions had stabilized after surgery, there was little change until shortly before delivery. In the last 24 h before calving maternal partial pressure of oxygen was high and fetal blood pH was low.
Subject(s)
Carbon Dioxide/blood , Cattle/blood , Electrolytes/blood , Fetal Blood , Oxygen/blood , Pregnancy, Animal , Animals , Cattle/physiology , Chlorides/blood , Female , Hydrogen-Ion Concentration , Potassium/blood , Pregnancy , Sodium/bloodABSTRACT
Concentrations of ionic and total calcium, magnesium, and inorganic phosphorus in plasma were determined in bovine fetuses and their mothers within the last month before delivery. Mean fetal concentrations were higher than corresponding maternal contents during the 22 days before delivery. Ionic and total calcium in plasma fell towards term in mother and fetus. Fetal phosphorus was elevated before parturition while maternal phosphorus fell. Maternal magnesium was elevated slightly at parturition.
