Experimental Evidence of Quantum Confinement Impairment In The Optical Properties of Annealed Lead Sulphide Thin Film

Recent characterizations of compounds are undoubtedly one of the avenues for the emergence of new semiconducting-light emitting diode (LED) devices. The industrial application of the lead sulphide thin film has been proposed. The lead sulphide thin film was grown by Chemical Bathe Deposition Technique (CBDT) and annealed at four temperatures of 100oC, 150oC, 200oC and 250oC. The samples were analyzed via the 6045 U-V spectrometer. The results shows that PbS thin film has a low transmittance value ranging from 0.204709% to 0.85722%; absorbance value ranging between 3.026% and 3.564%; reflectance value ranging from 81% to 114%; direct band gap was between 1.66eV to 1.78eV. Hence, the calculated refractive index ranges from 1.67 to 1.669. The evidence of quantum confinement impairment in each annealed samples was proofed. This shows that the optical tuning of the lead sulphide is dependent on the thermal control of its constituent's diamete

Evidence of local superconductivity in granular Bi nanowires fabricated by electrodeposition

An unusual enhancement of resistance (i.e., superresistivity) below a certain characteristic temperature Tsr was observed in granular Bi nanowires. This superresistive state was found to be dependent on the applied magnetic field (H) as well as the excitation current (I). The suppression of Tsr by magnetic field resembles that of a superconductor. The observed superresistivity appears to be related to the nucleation of local superconductivity inside the granular nanowire without long-range phase coherence. The phenomenon is reminiscent of the Bose-insulator observed previously in ultra thin two-dimensional (2D) superconducting films and 3D percolative superconducting films.Comment: 11 pages, 5 figures. submitted to PR

ANALYSIS OF PUBLIC AND PRIVATE - SECTORS PARTNERSHIP (PPP) IN HOUSING DELIVERY IN, NIGER STATE. NIGERIA

Abstract: One of the greatest challenge confronting both rural and urban residents in Niger State is the need to provide adequate shelter. This study examined the individual significant contribution of the public and private sector in public-private partnerships (PPP) in housing contracts in Niger State, Nigeria. The study review that PPP has so far achieved little success in providing decent and unaffordable housing accommodation to Nigerlites. Accordingly to Niger State housing corporation 2 bedrooms flat worth N3,500,000.00 and 3 bedrooms flat worth N4,500,000.00 so it’s clear that the houses are unaffordable to low and medium incomes earners. The researcher finding that the private sector in Niger State can be said to have contributed very little to the development of an urban project in the state, however, even this insignificant level of participation has been serious challenges by poor funding and lack of policy framework to regulate it activities. Therefore, it is paramount importance that the state should develop a regulatory framework and partner with the private sector in this regard so as to ensure that the resident of Niger State has access to this important component of the human environment. Researcher concluded that to ensure the effective participation of the private sector in housing delivery in Niger State in general and Minna in particular, the following recommendation has been put forward (1) Aside from providing enabling environment for the private sector to develop real estate, government should also invest more in provision of site and services scheme this will hasten the development of estate sector.  (2) The establishment a power federal mortgage bank (FMB) and  urban development bank would guarantee investors access to loan and other facilities needed for mass housing development.(3) strengthening the activities of the Niger State Ministry of land and housing in order to ensure that both the formal and informal neighborhood save provided with sanction and neighborhood facilities and (4) The establishment of a PPP steering committee in the Niger State that would be responsible for the general oversight of state’s PPP arrangement. (5) Finally, the study recommends that to ensure the success of public and private partnership in housing delivering, all tiers of government must strive to complement the weakness of the public sector with the strength of the private sector.

Remarks on Bootstrap Percolation in Metric Networks

We examine bootstrap percolation in d-dimensional, directed metric graphs in the context of recent measurements of firing dynamics in 2D neuronal cultures. There are two regimes, depending on the graph size N. Large metric graphs are ignited by the occurrence of critical nuclei, which initially occupy an infinitesimal fraction, f_* -> 0, of the graph and then explode throughout a finite fraction. Smaller metric graphs are effectively random in the sense that their ignition requires the initial ignition of a finite, unlocalized fraction of the graph, f_* >0. The crossover between the two regimes is at a size N_* which scales exponentially with the connectivity range \lambda like_* \sim \exp\lambda^d. The neuronal cultures are finite metric graphs of size N \simeq 10^5-10^6, which, for the parameters of the experiment, is effectively random since N<< N_*. This explains the seeming contradiction in the observed finite f_* in these cultures. Finally, we discuss the dynamics of the firing front

Plume motion and large-scale circulation in a cylindrical Rayleigh-B\'enard cell

We used the time correlation of shadowgraph images to determine the angle $\Theta$ of the horizontal component of the plume velocity above (below) the center of the bottom (top) plate of a cylindrical Rayleigh-B\'enard cell of aspect ratio $\Gamma \equiv D/L = 1$ ($D$ is the diameter and $L \simeq 87$ mm the height) in the Rayleigh-number range $7\times 10^7 \leq R \leq 3\times 10^{9}$ for a Prandtl number $\sigma = 6$. We expect that $\Theta$ gives the direction of the large-scale circulation. It oscillates time-periodically. Near the top and bottom plates $\Theta(t)$ has the same frequency but is anti-correlated.Comment: 4 pages, 6 figure

Subharmonic bifurcation cascade of pattern oscillations caused by winding number increasing entrainment

Convection structures in binary fluid mixtures are investigated for positive Soret coupling in the driving regime where solutal and thermal contributions to the buoyancy forces compete. Bifurcation properties of stable and unstable stationary square, roll, and crossroll (CR) structures and the oscillatory competition between rolls and squares are determined numerically as a function of fluid parameters. A novel type of subharmonic bifurcation cascade (SC) where the oscillation period grows in integer steps as $n (2\pi)/(\omega)$ is found and elucidated to be an entrainment process.Comment: 7 pages, 4 figure

High count rate {\gamma}-ray spectroscopy with LaBr3:Ce scintillation detectors

The applicability of LaBr3:Ce detectors for high count rate {\gamma}-ray spectroscopy is investigated. A 3"x3" LaBr3:Ce detector is used in a test setup with radioactive sources to study the dependence of energy resolution and photo peak efficiency on the overall count rate in the detector. Digitized traces were recorded using a 500 MHz FADC and analysed with digital signal processing methods. In addition to standard techniques a pile-up correction method is applied to the data in order to further improve the high-rate capabilities and to reduce the losses in efficiency due to signal pile-up. It is shown, that {\gamma}-ray spectroscopy can be performed with high resolution at count rates even above 1 MHz and that the performance can be enhanced in the region between 500 kHz and 10 MHz by using pile-up correction techniques

Resolving the Enhanced Flow Parameters for an In-depth Analysis of the MRI- Neuroimaging

The functionality of current neuroimaging using the MRI machine needs to be improved to diagnose more complex problems. A new mathematical concept based on the solutions of the Bloch NMR for MRI applications was adopted to resolve functionality problems- by the inclusion of molecular interactions. The signal loss factor 'E' caused by fluctuating velocity due to compartmental boundaries in the macromolecular sites was proposed to be the vital factor required for clinical diagnosis of cognitive impairment

Commissioning of the electron injector for the AWAKE experiment

The advanced wakefield experiment (AWAKE) at CERN is the first proton beam-driven plasma wakefield acceleration experiment. The main goal of AWAKE RUN 1 was to demonstrate seeded self-modulation (SSM) of the proton beam and electron witness beam acceleration in the plasma wakefield. For the AWAKE experiment, a 10-meter-long Rubidium-vapor cell together with a high-power laser for ionization was used to generate the plasma. The plasma wakefield is driven by a 400 GeV/c proton beam extracted from the super proton synchrotron (SPS), which undergoes a seeded self-modulation process in the plasma. The electron witness beam used to probe the wakefields is generated from an S-band RF photo-cathode gun and then accelerated by a booster structure up to energies between 16 and 20 MeV. The first run of the AWAKE experiment revealed that the maximum energy gain after the plasma cell is 2 GeV, and the SSM mechanism of the proton beam was verified. In this paper, we will present the details of the AWAKE electron injector. A comparison of the measured electron beam parameters, such as beam size, energy, and normalized emittance, with the simulation results was performed