The Effects of Solar Panel Temperature on the Power Output Efficiency in Calabar, Nigeria

Background: The current push for adoption of alternative energysources necessitates research into parameters that would enhancethe optimum harvest of the benefits of such efforts.Purpose: To determine the effects of solar panel temperature on itsefficiency in Calabar, Nigeria, by determining the output currentand voltage changes due to solar panel temperature.Materials and Methods: A modern digital thermometer, Model220k type, and Alda ADV 890C digital multimeter, were used toobtain measurements of solar panel temperatures, current andvoltage, respectively, in Calabar, Nigeria. Comparisons were madeof the values of current and voltage obtained with solar paneltemperature changes, and efficiency of the output of the solarpanels determined by calculation using efficiency as given byKachhava (2003).Results: Results indicate that a maximum output current of18.4x10-1A was recorded at 42.8oC. Beyond this temperature theoutput current dropped down to 12x10-1A at 54.8oC. The voltageoutput remained relatively stable as solar panel temperatureincreased. Power output efficiency dropped from 82.3% at 42.8oCto 52.4% at 54.8oC.Conclusion: High solar panel temperatures may have adverseeffects on solar panel efficiency. The result obtained in this studysuggest a maximum operating temperature of solar panel inCalabar, Nigeria

Alteration in biochemical indices following administration of seafood (Thais coronata) extract

Seafood consumption has been a way of life to most people especially those that leave in riverine areas, because seafoods are known to contain many nutrients that are essential for healthy living. Consequently, this research therefore seeks to investigate the effect of these nutritive components of Thais coronata on biochemical indices of albino Wistar rats. Fourty five male albino Wister rats weighing between 180-220 g were assigned into 3 groups of fifteen rats each in metabolic cages and were given rat feed and drinking water ad libitum. Two test doses (low dose 7.0 mg protein/ml and  high dose 52 mg protein/ml) were selected  and  administered  to  two  groups  of  rats  orally  and  daily  for  six  weeks,  while  a third group of rats served as the control, n = 15. At the expiration of the feeding period, blood samples were obtained from all the rats via cardiac puncture for the analysis of the various biochemical indices. Both the low and high doses of the extract produced significant increases in HDLc (P<0.001) compared with control. k (P<0.001), HCO3- (P<0.01) and Ca2+ (P<0.001) were also significantly increased in the  extract treated groups. The extract groups had significant reductions in ALT (P<0.001), ALP (P<0.001), Na+ (P<0.001) and Cl- (P<0.001) compared with control. Also Tc (P<0.001), TG (P<0.001), LDL (P<0.001) and VLDLc (P<0.001) were significantly decreased in the extract treated group. In conclusion seafood consumption is of immense benefit to health because it serves to regulate the lipid profile, electrolytes and enzyme concentrations in blood. DOI: http://dx.doi.org/10.5281/zenodo.58078

Synthesis, stereochemistry and antimicrobial activity of copper(II) and nickel(II) complexes of 4-phenylsemicarbazones

2-Acetylpyridine-(4-phenylsemicarbazone) and o-vanillin-(4-phenylsemicarbazone) have been prepared and characterized on the basis of elemental analyses, infrared, electronic, 1H and 13C NMR spectra. Several nickel(II) and copper(II) complexes have been obtained from these ligands. The IR spectra of the ligands as well as those of their complexes suggest that 2-acetylpyridine-(4-phenylsemicarbazone) is a neutral tridentate molecule while o-vanillin-(4-phenylsemicarbazone) is a monobasic tridentate molecule. On the basis of the analytical data, magnetic moments and spectral data, a square-planar geometry has been proposed for the nickel(II) and copper(II) complexes with these ligands. Some representative complexes of copper(II) and nickel(II) were found to have remarkable antifungal and antibacterial activity.KEY WORDS: 4-Phenylsemicarbazone, Metal complexes, Stereochemistry, Antimicrobial activity Bull. Chem. Soc. Ethiop. 2011, 25(3), 361-370

Synthesis, crystal structure and magnetic properties of [Cu(mal)(abpt)(H2O)].3/2H2O and [Cu2(sq)(abpt) 2].2H2O (mal = malonate, sq = squarate, abpt =4-amino-3,5-di-2-pyridyl-4H-1,2,4 triazole)

Two new mixed-ligand complexes of formula [Cu(mal)(abpt)(H2O)].3/2H2O (1) and [Cu2(sq)(abpt) 2].2H2O (2) [mal = malonate, abpt = 4-amino-3,5-di-2-pyridyl-4H-1,2,4 triazole and sq = squarate], have been prepared and characterized by X-ray crystal structure determination and magnetic studies. Complex 1 crystallizes in the monoclinic system, space group C2/c, with a = 14.0086(2) Å, b = 10.0980(2) Å, c = 25.630(4) Å; β = 97.5900(10) o, and Z = 8. Complex 2 crystallizes in the triclinic system, space group P-1 with a = 7.5696(15) Å, b = 8.4697(17) Å, c = 11.049(2) Å; β = 93.00(3)o,  α = 96.98(3), γ = 90.111(3) and Z = 1. Complex 1 consist of a neutral mononuclear [Cu(mal)(abpt)(H2O)] unit and water molecule of crystallization in a distorted square pyramidal coordination sphere, while complex 2 is viewed as being made up of [Cu(sq)(abpt)2] units with the squarato ligand bridging the two copper(II) cations. Variable temperature magnetic behaviour of the complexes reveals the existence of weak antiferromagnetic interaction for complex 1 and weak ferromagnetic intrachain interaction for complex 2.KEY WORDS: Copper(II) complexes, Mixed-ligand, Magnetic properties, Malonate, Squarate, 4-Amino-3,5-di-2-pyridyl-4H-1,2,4 triazoleBull. Chem. Soc. Ethiop. 2011, 25(1), 53-60

Summary of the Very Large Hadron Collider Physics and Detector Workshop

One of the options for an accelerator beyond the LHC is a hadron collider with higher energy. Work is going on to explore accelerator technologies that would make such a machine feasible. This workshop concentrated on the physics and detector issues associated with a hadron collider with an energy in the center of mass of the order of 100 to 200 TeV

Limits on WWgamma and WWZ Couplings from W Boson Pair Production

The results of a search for W boson pair production in pbar-p collisions at sqrt{s}=1.8 TeV with subsequent decay to emu, ee, and mumu channels are presented. Five candidate events are observed with an expected background of 3.1+-0.4 events for an integrated luminosity of approximately 97 pb^{-1}. Limits on the anomalous couplings are obtained from a maximum likelihood fit of the E_T spectra of the leptons in the candidate events. Assuming identical WWgamma and WWZ couplings, the 95 % C.L. limits are -0.62<Delta_kappa<0.77 (lambda = 0) and -0.53<lambda<0.56 (Delta_kappa = 0) for a form factor scale Lambda = 1.5 TeV.Comment: 10 pages, 1 figure, submitted to Physical Review

Metathesis of Fatty Acid Ester Derivatives in 1,1-Dialkyl and 1,2,3-Trialkyl Imidazolium Type Ionic Liquids

The self-metathesis of methyl oleate and methyl ricinoleate was carried out in the presence of ruthenium alkylidene catalysts 1–4 in [bmim] and [bdmim][X] type ionic liquids (RTILs) (X = PF6−, BF4− and NTf2−) using the gas chromatographic technique. Best catalytic performance was obtained in [bdmim][X] type ionic liquids when compared with [bmim][X] type ionic liquids. Catalyst recycling studies were also carried out in the room temperature ionic liquids (RTILs) with catalysts 1–4 in order to explore their possible industrial application

Search for a Fourth Generation Charge -1/3 Quark via Flavor Changing Neutral Current Decay

We report on a search for pair production of a fourth generation charge -1/3 quark (b') in pbar p collisions at sqrt(s) = 1.8 TeV at the Fermilab Tevatron using an integrated luminosity of 93 pb^-1. Both quarks are assumed to decay via flavor changing neutral currents (FCNC). The search uses the signatures gamma + 3 jets + mu-tag and 2 gamma + 2 jets. We see no significant excess of events over the expected background. We place an upper limit on the production cross section times branching fraction that is well below theoretical expectations for a b' quark decaying exclusively via FCNC for b' quark masses up to m(Z) + m(b).Comment: Eleven pages, two postscript figures, submitted to Physical Review Letter

Search for R-parity Violating Supersymmetry in Dimuon and Four-Jets Channel

We present results of a search for R-parity-violating decay of the neutralino chi_1^0, taken to be the Lightest Supersymmetric Particle. It is assumed that this decay proceeds through one of the lepton-number violating couplings lambda-prime_2jk (j=1,2; k=1,2,3). This search is based on 77.5 pb-1 of data, collected by the D0 experiment at the Fermilab Tevatron in ppbar collisions at a center of mass energy of 1.8 TeV in 1992-1995.Comment: 10 pages, 3 figure