Prediction and analysis of long-term variability of temperature and salinity in the Irish Sea

The variability of temperature and salinity in the Irish Sea over the 40 year period 1960 - 1999 is investigated using a free-running fine-resolution local area model. The skill of the model to represent observed temperature and salinity variability is assessed using conductivity-temperature-depth survey data ( 3397 profiles) and a long time series of measurements from Cypris station (southwest of Isle of Man). This clearly demonstrates that the model can reproduce the observed seasonal and longer-term cycles in temperature, with mean and RMS errors of - 0.01 degrees C and 0.78 degrees C. Particularly apparent is the long-term warming trend at Cypris station and throughout the model domain. Model estimates of salinity are less accurate and are generally too saline (mean and RMS errors are 0.79 and 0.98 practical salinity units). Inaccuracies are likely to arise from boundary conditions and forcing (riverine and surface). However, while absolute values are not particularly well represented, the model reproduces many of the trends in the salinity variability observed at Cypris station, suggesting that the dominant physical processes in the Irish Sea, with timescales up to similar to 3 years, are well represented. The model is also used to investigate the variability in temperature stratification. While stratification is confined to approximately the same geographical area in each year of the simulation, there is significant variability in the timing of the onset and breakdown of stratification and in the peak surface to bed temperature difference. Together, these results suggest that a local area model with limited boundary conditions may be sufficiently accurate for climatic investigation of some (locally forced) parameter

Study of photoconductive indium antimonide

Indium antimonide (InSb) material was assessed for use as photoconductive infrared detectors under low background conditions. Such detectors must be more rugged, and have lower capacitance, than the common photovoltaic InSb detector. Electronic grade n-type InSb was etched to 50 micrometers thickness, and tin and gold contacts were applied by evaporation. The test devices showed a relatively low ultimate impedance: 7 Mohms at 4.2 K. This was attributed to the presence of impurity levels of very shallow energies, and this material was judged unsuitable for low background detection

Forbidden Ca 2 in the sun unmasked by way of Venus

Eleven high-dispersion spectra of Venus, taken with blue Doppler shifts have permitted the unmasking of the 7323.88A forbidden line of Ca II from terrestrial absorption. An equivalent width is obtained of 7.4 + or - 0.4mA for this line in integrated sunlight. Our value of W sub lambda is smaller than previous values and much more accurate. The HSRA solar model gives a solar calcium abundance of A sub Ca = 6.21

Weight, volume, and center of mass of segments of the human body

Weight, volume, and center of mass of segments of human bod

Laser velocimeter systems analysis applied to a flow survey above a stalled wing

A laser velocimeter operating in the backscatter mode was used to survey the flow above a stalled wing. Polarization was used to separate the two orthogonal velocity components of the fringe-type laser velocimeter, and digital counters were used for data processing. The velocities of the kerosene seed particles were measured with less than 2 percent uncertainty. The particle velocity measurements were collected into histograms. The flow field survey was carried out above an aspect-ratio-8 stalled wing with an NACA 0012 section. The angle of attack was 19.5 deg, the Mach number was 0.49, and the Reynolds number was 1,400,000. The flow field was characterized by the periodic shedding of discrete vortices from near the crest of the airfoil

Determination of metals in pepper by flame atomic absorption spectroscopy

The health risk of dietary intake of metals by humans cannot be over-emphasized, especially metalcontaminated farm produce from an abandoned waste dump site. Metals could contaminate farm produce during pre- and post-harvest periods. The metal (zinc, copper, chromium, iron, manganese and cobalt) contents of Capsicum annum, Capsicum chinens and Capsicum frutescens pepper samples (harvested from an abandoned waste dump site in Gbarantoru in Bayelsa State) were determined and compared with WHO permissible levels. The pepper samples were crispy-dried, ground to fine powder, and digested with an acid mixture of sulphuric acid, perchloric acid and nitric acid in the ratio of 1:4:40. Prepared samples were analyzed using flame atomic absorption spectrophotometer. The results showed a wide range of concentrations: Capsicum annuum (Zn = 40.28 mg/kg, Cu = 4.17 mg/kg, Cr = 3.32 mg/kg, Fe = 105.23 mg/kg, Mn = 0.54 mg/kg, Co = 0.69 mg/kg), Capsicum chinens (Zn = 54.48 mg/kg, Cu = 4.22 mg/kg, Cr = 2.81 mg/kg, Fe = 158.33 mg/kg, Mn = 0.66 mg/kg, Co = 0.73 mg/kg), Capsicum frutescens (Zn = 47.45 mg/kg, Cu = 4.36 mg/kg, Cr = 3.20 mg/kg, Fe = 63.13 mg/kg, Mn = 0.59 mg/kg, Co = 0.77 mg/kg). The metal concentrations of the three hot pepper samples were found to be below WHO- permissible limits except for zinc in Capsicum chinens, which was found to be higher than the permissible limit. These species of pepper grown in this abandoned waste dumpsite are safe for food as stipulated by WHO.Keywords: Metals, pepper, flame, atomic absorption, waste, dumpsite

A comparison between pulsed and CW laser annealing for solar cell applications

The application of laser processing in solar cell fabrication is considered. Specific emphasis is placed on a process developed for the fabrication of a 16.6% silicon solar cell using pulsed laser processing. Results are presented which compare pulsed laser annealing with CW laser annealing in solar cell fabrication