1,081 research outputs found
Transport on flexible Rydberg aggregates using circular states
Assemblies of interacting Rydberg atoms show promise for the quantum
simulation of transport phenomena, quantum chemistry and condensed matter
systems. Such schemes are typically limited by the finite lifetime of Rydberg
states. Circular Rydberg states have the longest lifetimes among Rydberg states
but lack the energetic isolation in the spectrum characteristic of low angular
momentum states. The latter is required to obtain simple transport models with
few electronic states per atom. Simple models can however even be realized with
circular states, by exploiting dipole-dipole selection rules or external
fields. We show here that this approach can be particularly fruitful for
scenarios where quantum transport is coupled to atomic motion, in adiabatic
excitation transport or quantum simulations of electron-phonon coupling in
light harvesting. Additionally, we explore practical limitations of flexible
Rydberg aggregates with circular states and to which extent interactions among
circular Rydberg atoms can be described using classical models.Comment: 9 Pages, 5 Figure
Author Productivity and Collaboration Among Academic Scientists in Modibbo Adama University of Technology, Yola
A lot of researches on author productivity and collaboration were carried out in different fields. Many of the researches established that productive, active and prolific authors are also highly collaborative. This study determines whether the most productive author among the academic scientists in Modibbo Adama University of technology, Yola, for the period 2001 – 2010 is also the most collaborative. The study used the weighted-average method to determine the extent of author collaboration. Spearman rank correlation coefficient was used to determine the correlation between productivity and collaboration among the subjects of the study. The study reveals that thereis high degree of collaboration among the scientists and that the productive authors correlated positively with the collaborative authors
The Use of Internet by Academic Scientists in Modibbo Adama University of Technology, Yola
The internet is an important tool for communication and retrieval of information. This study examined the use of internet in communication and retrieval of information by scientists in Modibbo Adama University of Technology, Yola.The survey method was used for the study. A total of 95 scientists in the school of pure and applied sciences (SPASS) constituted the population of the study. Result of the study shows that majority (60.45%0 of the scientists use the internet occasionally to access information. They do not take advantage of the vast and rich knowledgepreserved and communicated through e-books, e-thesis, and digital archives. Finally, majority of the scientists (60.49%) use the internet to get support or sponsorship for studies rather than for research. Some of therecommendations of the study include: The necessary requirement that universities should have good Information Technology (IT) infrastructure such as the internet in order to create easy information access and retrieval as well as to disseminate research findings for wider use; To overcome erratic retrieval problems and for fast access of wide and current range of resources so as to achieve maximum user satisfaction with economy of time, use of e-books, ethesis and digital archives becomes the best option; The scientists also need to enhance their skills of internet surfing by way of regular training on the use and advantages of the internet
Information and Communication Network Among Natural Scientists In Ahmadu Bello University, Zaria.
This study tries to find out the extent of information and communication networks among natural scientists in Ahmadu Bello University, Zaria. Their ways of information sharing, and the extent of their participation in information networking were investigated. Using two (2) research questions, data was collected from 299 pure and applied scientists in five (5) faculties in the university. The data was analysed by descriptive statistics. The
findings showed that the natural scientists in the university significantly share information among themselves. Suggestions were made to facilitate the development information networking among the Nigerian scientists. Samaru Journal of Information Studies Vol. 7 (1) 2007: pp. 13-1
Interfacial shear in adiabatic downward gas/liquid co-current annular flow in pipes
Interfacial friction is one of the key variables for predicting annular two-phase flow behaviours in vertical pipes. In order to develop an improved correlation for interfacial friction factor in downward co-current annular flow, the pressure gradient, film thickness and film velocity data were generated from experiments carried out on Cranfield University’s Serpent Rig, an air/water two-phase vertical flow loop of 101.6 mm internal diameter. The air and water superficial velocity ranges used are 1.42–28.87 and 0.1–1.0 m/s respectively. These correspond to Reynolds number values of 8400–187,000 and 11,000–113,000 respectively. The correlation takes into account the effect of pipe diameter by using the interfacial shear data together with dimensionless liquid film thicknesses related to different pipe sizes ranging from 10 to 101.6 mm, including those from published sources by numerous investigators. It is shown that the predictions of this new correlation outperform those from previously reported studies
Vertical annular gas–liquid two-phase flow in large diameter pipes
Gas–liquid annular two phase flow in pipes is important in the oil and gas,
nuclear and the process industries. It has been identified as one of the most
frequently encountered flow regimes and many models (empirical and
theoretical) for the film flow and droplet behaviour for example have been
developed since the 1950s. However, the behaviour in large pipes (those with
diameter greater than 100 mm) has not been fully explored. As a result, the two-
phase flow characteristics, data, and models specifically for such pipes are
scarce or non-existent such that those from smaller pipes are extrapolated for
use in design and operation. Many authors have cautioned against this
approach since multiphase pipe flow behaviour is different between small and
large pipes. For instance the typical slug flows seem not to occur in vertical
upwards flows when the pipe diameter exceeds 100 mm. It is therefore
imperative that theoretical models and empirical correlations for such large
diameter pipes are specifically developed.
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Nigeria’s Federal Legislators’ Bloated Remuneration and Implications for Public Policy and Good Governance
This paper is a descriptive type. The study employs secondary data that was sourced from journal articles, online materials, government documentaries, and dailies to examine the huge salaries and other allowances “earned” by members of the National Assembly of the Federal Republic of Nigeria. The study is against the background of the controversies that enormous salaries and allowances of legislators have generated in the country since the return of democratic rule in 29th May; 1999. Despite the biting economic situation, poverty, unemployment and collapsed public infrastructures, members of the National Assembly continue to receive controversial salaries and allowances, and still often clamor for more. This study examines this issue and its implications for the country. The study concludes by proffering policy options which include but are not limited to giving serious thought to the need for part-time legislators who would only be entitled to sitting allowance, a significant reduction in the payments of all political office holders, and reduction of the two chambers of the National Assembly in Nigeria to one house-unicameral legislature, or at worst; reduction in the number of national lawmakers to maintain a cost-effective legislature.
Partisan Politics, Political Culture and Restructuring Drive for Good Governance in Nigeria
This paper discusses a number of partisan political attitudes among Nigerians such as party switching; especially by incumbent political office holders to a ruling party, taking kickbacks for party funding, use of money and material things to lure electorate, recruitment of party-militia to foment violence, party control by incumbent political office holders, and followers docile attitude to leadership service, and examines how they have constituted wrong political culture. The study also discusses the effects of such attitudes on good governance in Nigeria, and offers policy options for restructuring the behaviours. The study relied on secondary data and was content analyzed. The study argues for a need to restructure the wrong partisan behaviours among political stakeholders because they have made good governance elusive, incumbent political office holders more powerful and corrupt, partisan politics patron-client inclined and breed violence during electioneering periods. A number of restructuring policy-agenda were offered to move the country forward and put governance in enviable position
Gas/liquid flow behaviours in a downward section of large diameter vertical serpentine pipes
An experimental study on air/water flow behaviours in a 101.6 mm i.d. vertical pipe with a serpentine configuration is presented. The experiments are conducted for superficial gas and liquid velocities ranging from 0.15 to 30 m/s and 0.07 to 1.5 m/s, respectively. The bend effects on the flow behaviours are significantly reduced when the flow reaches an axial distance of 30 pipe diameters or more from the upstream bend. The mean film thickness data from this study has been used to compare with the predicted data using several falling film correlations and theoretical models. It was observed that the large pipe data exhibits different tendencies and this manifests in the difference in slope when the dimensionless film thickness is plotted as a power law function of the liquid film Reynolds number
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