Laser-driven secondary sources of X-rays and particles at ELI Beamlines (Conference Presentation)

2019 ◽  
Author(s):  
Georg Korn ◽  
Sergei V. Bulanov ◽  
Daniele Margarone ◽  
Jaroslav Nejdl ◽  
Alexander Molodozhentsev ◽  
...  
Keyword(s):  
X Rays ◽  
Secondary Sources

scholarly journals RETHINKING A CULTURAL POLICY FOR NATIONAL SECURITY IN NIGERIA

2020 ◽  
Vol 1 (2) ◽  
Author(s):  
Emmanuel Ayila Agaku ◽  
Martins Moses Agena
Keyword(s):  
National Security ◽  
Cultural Values ◽  
Political Violence ◽  
Cultural Policy ◽  
Cultural Dimensions ◽  
X Rays ◽  
The Sustainable Development ◽  
Participatory Communication ◽  
Secondary Sources ◽  
The People

Nigeria is in pressing need of a cultural policy that could promote cultural values. The challenge of cultural erosion has affected the capacity of the country to ensure the security and welfare of the people for the sustainable development of the country. This article, therefore, examines the cultural dimensions of the country’s national security problem. In addition to deploying qualitative research methodology, the researchers adopt a theoretical exploration of secondary sources for the article. The paper x-rays some related literature that unveil many security challenges that have to do with conflicts in the way of life of the people, such as, the Muslim extremists of Marwa, Maitatsine, El-zakzaki and their liberal counterparts in Kano, Maiduguri, Zaria, Gombe, Yola and so on, at various times. Countless instances of ethno-religious conflicts have occurred between Christians and Muslims in Bauchi, Kano, Kafanchan, Zango-Kataf, Kaduna, and Nasarawa among other parts of Nigeria.  There have been sectarian conflicts in Nasarawa, Benue, some parts of South-East, South-West and South-South of Nigeria.  More recently, there has emerged some difficult insecurity problems characterised by political violence, Boko Haram terrorists, banditry, kidnapping, cattle rustling, Fulani herdsmen attacks, militancy and so on. In addition to the above-mentioned plethora of insecurity, there are on daily occurrence instances of corruption and crimes such as suicide attacks, armed-robbery, oil theft, rape and so on. The article attempted a theoretical matrix of ‘culture of security’ and ‘security of culture’. The paper therefore recommends a cultural policy could promote cultural education, values, sensitivity, and unity, as well as commitment through participatory communication by nationalist individuals and their involvement in the nation-building efforts, necessary to avert imminent crisis in the country.

scholarly journals A Theoretic Perspective on Critical Communications, Mass Media and Effectual Democracy in Nigeria

2020 ◽  
Vol 16 (8) ◽  
pp. 82
Author(s):  
Aaron Ola Ogundiwin ◽  
Joel N. Nwachukwu ◽  
Funminiyi Jacob Babajide
Keyword(s):  
Mass Media ◽  
Political Elite ◽  
The Political ◽  
X Rays ◽  
Secondary Sources ◽  
The Press ◽  
The Media ◽  
The Mass Media ◽  
The Government ◽  
Inclusive Governance

In contemporary times, democracy has become the political buzzword and, indeed, the basic acceptable form of government with the emergence of liberalism which links democracy with freedom, consent, and political and legal equality. The mass media – which include newspapers, radio and television – play a prominent role in governance and democratic sustainability of any state. In fact, it is a truism that the media serve as the watchdog of governmental activities, ensuring that quality information with which the governed can hold their leaders accountable is made available. The mass media were actively involved in the struggles against colonialism and military rule, as well as the eventual restoration of democratic government in Nigeria. However, in Nigeria, the mass media are fast becoming a pawn in the hands of the government and party in power in particular, and are found in conspiracy with the political elite class in general. This article takes on the contributions of the mass media to effectual democracy in Nigeria. Using agenda setting theoretical framework, it x-rays the effectiveness and shortcomings of the media in delivering on its mandate as the fourth estate of the realm towards ensuring that democratic practices in Nigeria produce the intended result of promoting good and inclusive governance. The paper adopts qualitative research design with data drawn from secondary sources only. It equally uses descriptive and content data analysis. It is found that the mass media have indeed been the middlemen in entrenching democracy in Nigeria but these efforts are being undermined by pecuniary, ownership, political and structural-institutional influences. It is concluded that while the mass media strive to ensure the general inclusion of the populace in the process of governing which fulfills a core democratic tenet, they can do more to overcome the challenges. Among other things, this paper recommends that the government should be deliberate in guaranteeing the freedom of the press to allow for free transmission of information between the government and the people without fear or favour, and likewise, the press should be professional, objective, critical and independent in their reportage, embracing the virtue of investigative journalism.

A Secondary-Source, Energy-Dispersive X-Ray Spectrometer and its Application to Quantitative Analytical Chemistry

1973 ◽  
Vol 17 ◽  
pp. 571-583
Author(s):  
R. P. Larsen ◽  
J. O. Karttunen
Keyword(s):  
Background Radiation ◽  
Energy Dispersive ◽  
Excitation Source ◽  
Secondary Source ◽  
X Rays ◽  
X Ray ◽  
Secondary Sources ◽  
The Individual ◽  
Detection Instrument

AbstractAn energy-dispersive X-ray spectrometer that (1) uses as the primary excitation source the power supply and tungsten X-ray tube from a conventional crystal spectrometer (General Electric XRD-6) and (2) uses as the secondary excitation source elemental metal foils that are readily interchangeable has been built and operated. The use of an X-ray tube with a high-voltage capability, 75 kilovolts max, enables the determination of elements with atomic numbers as high as 66 (terbium) to be based on the K series of X-rays; the highpower capability, 3.7 kilowatts max, enables a particularly intense beam of X-rays to be generated by the secondary source and hence, provides a particularly high detection capability for trace elements in a sample. An instrument that uses interchangeable secondary sources to irradiate the samples has several advantages over those instruments in which excitation is accomplished by direct irradiation with an X-ray tube: (1) the background radiation in the energy range where the X-rays of interest are measured is several orders of magnitude lower and is very uniform and (2) the energy of the excitation radiation can be closely matched to the absorption edges of the elements of interest in the sample.In the application of the instrument, particular emphasis has been placed on the development of tectmiques that will enable an energy-dispersive X-ray spectrometer to be used as the detection instrument for quantitative elemental analysis. Methods for the determination of the individual rare earths, plutonium and uranium at the microgram level with an accuracy of ± 1% are outlined and for the determination of plutonium and uranium at the milligram level with an accuracy of ± 0.1% are proposed.

scholarly journals YOUTH EMPOWERMENT FOR SUSTAINABLE ECONOMIC DEVELOPMENT IN NIGERIA

2020 ◽  
Vol 7 (1) ◽  
pp. 136-142
Author(s):  
Aja Accord ◽  
Keyword(s):  
Economic Development ◽  
Human Resources ◽  
Primary Source ◽  
Youth Empowerment ◽  
X Rays ◽  
Secondary Sources ◽  
Sustainable Economic Development ◽  
New Strategy ◽  
Academic Publications ◽  
Age Range

Youth empowerment is the key to sustainable development. Nigeria which stands as the youngest population in Africa has more than 50% of her population fall within the age range known as Youths (16-39)(NBS Report, 2018).The implication of this reality is that Nigeria has a massive prospect for economic development but that will be if the country can efficiently harness this human resources efficiently. Though numerous youth empowerment programs have been put in place by the Nigerian government, those programs lack sustainability. Today, the sad reality is that most of the youths in Nigeria are unemployed.The Nigeria bureau of statistics states that about 20.9 Million Nigerians were unemployed as at the third quarter of 2018, this data also shows that more than 80% of this unemployed Nigerians are youths, the working population of the country.With such a population of youths and drastic dilemma of unemploymentand poverty in the country, there is a need for government to adopt new strategy to engage this young population in a very productive way.This paper examines youth empowerment concepts that can be used to engage this huge human resources (the youth in Nigeria) in a productive way that will build sustainable economic development. The paper X-rays youth empowerment concept and their developmental potentials if they are carefully implemented with regulatory frame work to drive their sustainability.The study utilized questionnaires as the primary source of data and research reports and academic publications as the secondary sources of data. The study recommended that the youth empowerment programs should be revamped in a strategic way that will engage the youths and add massive revenue to the economy.

scholarly journals Agitations for Regime Change and Political Restructuring: Implications on National Integration and Development in Nigeria

2021 ◽  
Vol 21 (3) ◽  
pp. 1-26
Author(s):  
Igboke C. Shedrack
Keyword(s):  
World War Ii ◽  
Ethnic Groups ◽  
Skill Acquisition ◽  
Regime Change ◽  
National Development ◽  
Regional Government ◽  
X Rays ◽  
National Integration ◽  
Secondary Sources ◽  
Nation States

The formation of organizations at global, regional and sub-regional levels among nation-states, especially after the World War II in 1945 was to nip n the bud situation that could escalate into war and promote global peace. It was also to promote political, economic and socio-cultural unity and welfare among member states. It was on this premise that the United Nations (UN), organizations of Africa Union (OAU) now AU, Arab League, European Union (EU), etc were formed to promote unity among nation states. The main thrust of this paper was to analyze the implications of agitation by various ethnic groups on national integration and development in Africa. The paper also x-rays the nexus between leadership failure and development in Nigeria. The study was anchore0d on the structural functionalism theory to address agitations and conflict among ethnic groups in Nigeria. This theory recognizes the need for restructuring the political system that will enable each component unit to function effectively for sustainable development. The study relied on much of the data scooped from secondary sources such as textbooks, internet materials, magazines, newspaper, journals etc. The study found out that agitations and conflict among ethnic groups was threat to national integration and development, citing the case of Indigenous people of Biafra popularly known as IPOB, Niger Delta militant, etc. The paper concluded that national integration was the bedrock to peace and national development in Nigeria. It was also recommended that government should desist from the actions and inactions that are threat to national integration and peace. The study recommended that Nigerian government should seriously focus on empowerment and investment in youth, through education, skill acquisition and also implementing policy that will eliminate all forms of agitations. The paper equally recommended adoption of regional government and true Federalism to address the problems of national development. Keywords: Agitations, regime change, political restructuring, integration, and development

White-Light Coronal Structures: Streamers and CMEs

1994 ◽  
Vol 144 ◽  
pp. 82
Author(s):  
E. Hildner
Keyword(s):  
Emission Line ◽  
Electron Density ◽  
White Light ◽  
Coronal Mass Ejections ◽  
X Rays ◽  
Solar Cycles ◽  
Temperature Function ◽  
X Ray ◽  
Eclipse Observations ◽  
Coronal Structures

AbstractOver the last twenty years, orbiting coronagraphs have vastly increased the amount of observational material for the whitelight corona. Spanning almost two solar cycles, and augmented by ground-based K-coronameter, emission-line, and eclipse observations, these data allow us to assess,inter alia: the typical and atypical behavior of the corona; how the corona evolves on time scales from minutes to a decade; and (in some respects) the relation between photospheric, coronal, and interplanetary features. This talk will review recent results on these three topics. A remark or two will attempt to relate the whitelight corona between 1.5 and 6 R⊙to the corona seen at lower altitudes in soft X-rays (e.g., with Yohkoh). The whitelight emission depends only on integrated electron density independent of temperature, whereas the soft X-ray emission depends upon the integral of electron density squared times a temperature function. The properties of coronal mass ejections (CMEs) will be reviewed briefly and their relationships to other solar and interplanetary phenomena will be noted.

Emergence of Twisted Magnetic Flux Related Sigmoidal Brightening

2000 ◽  
Vol 179 ◽  
pp. 263-264
Author(s):  
K. Sundara Raman ◽  
K. B. Ramesh ◽  
R. Selvendran ◽  
P. S. M. Aleem ◽  
K. M. Hiremath
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Magnetic Flux ◽  
Ultra Violet ◽  
Active Regions ◽  
Morphological Properties ◽  
Energy Storage And Conversion ◽  
The Sun ◽  
X Rays ◽  
The Magnetic Field

Extended AbstractWe have examined the morphological properties of a sigmoid associated with an SXR (soft X-ray) flare. The sigmoid is cospatial with the EUV (extreme ultra violet) images and in the optical part lies along an S-shaped Hαfilament. The photoheliogram shows flux emergence within an existingδtype sunspot which has caused the rotation of the umbrae giving rise to the sigmoidal brightening.It is now widely accepted that flares derive their energy from the magnetic fields of the active regions and coronal levels are considered to be the flare sites. But still a satisfactory understanding of the flare processes has not been achieved because of the difficulties encountered to predict and estimate the probability of flare eruptions. The convection flows and vortices below the photosphere transport and concentrate magnetic field, which subsequently appear as active regions in the photosphere (Rust & Kumar 1994 and the references therein). Successive emergence of magnetic flux, twist the field, creating flare productive magnetic shear and has been studied by many authors (Sundara Ramanet al.1998 and the references therein). Hence, it is considered that the flare is powered by the energy stored in the twisted magnetic flux tubes (Kurokawa 1996 and the references therein). Rust & Kumar (1996) named the S-shaped bright coronal loops that appear in soft X-rays as ‘Sigmoids’ and concluded that this S-shaped distortion is due to the twist developed in the magnetic field lines. These transient sigmoidal features tell a great deal about unstable coronal magnetic fields, as these regions are more likely to be eruptive (Canfieldet al.1999). As the magnetic fields of the active regions are deep rooted in the Sun, the twist developed in the subphotospheric flux tube penetrates the photosphere and extends in to the corona. Thus, it is essentially favourable for the subphotospheric twist to unwind the twist and transmit it through the photosphere to the corona. Therefore, it becomes essential to make complete observational descriptions of a flare from the magnetic field changes that are taking place in different atmospheric levels of the Sun, to pin down the energy storage and conversion process that trigger the flare phenomena.

The Clinical, Roentgenological and Morphological Effects of an Acute Exposure of Phosgene on the Lungs of Dogs

1971 ◽  
Vol 29 ◽  
pp. 236-237
Author(s):  
R. F. Bils ◽  
W. F. Diller ◽  
F. Huth
Keyword(s):  
Latent Period ◽  
Chemical Industry ◽  
Toxic Substance ◽  
Lung Edema ◽  
X Rays ◽  
Beagle Dogs ◽  
Male And Female ◽  
Morphological Alterations ◽  
Before And After ◽  
Electron Microscopes

Phosgene still plays an important role as a toxic substance in the chemical industry. Thiess (1968) recently reported observations on numerous cases of phosgene poisoning. A serious difficulty in the clinical handling of phosgene poisoning cases is a relatively long latent period, up to 12 hours, with no obvious signs of severity. At about 12 hours heavy lung edema appears suddenly, however changes can be seen in routine X-rays taken after only a few hours' exposure (Diller et al., 1969). This study was undertaken to correlate these early changes seen by the roengenologist with morphological alterations in the lungs seen in the'light and electron microscopes.Forty-two adult male and female Beagle dogs were selected for these exposure experiments. Treated animals were exposed to 94.5-107-5 ppm phosgene for 10 min. in a 15 m3 chamber. Roentgenograms were made of the thorax of each animal before and after exposure, up to 24 hrs.

Chemical Species Identification in an SEM by Changes in Emitted X-Ray Energies

1974 ◽  
Vol 32 ◽  
pp. 570-571
Author(s):  
R. H. Duff
Keyword(s):  
Species Identification ◽  
Valence Electron ◽  
Chemical Species ◽  
X Rays ◽  
Chemical Bonds ◽  
Small Shift ◽  
X Ray ◽  
Electron Transitions ◽  
Peak Energy ◽  
Chemical Combination

A material irradiated with electrons emits x-rays having energies characteristic of the elements present. Chemical combination between elements results in a small shift of the peak energies of these characteristic x-rays because chemical bonds between different elements have different energies. The energy differences of the characteristic x-rays resulting from valence electron transitions can be used to identify the chemical species present and to obtain information about the chemical bond itself. Although these peak-energy shifts have been well known for a number of years, their use for chemical-species identification in small volumes of material was not realized until the development of the electron microprobe.

Influence of X-Ray Induced Fluorescence on Energy Dispersive X-Ray Analysis of Thin Foils

1977 ◽  
Vol 35 ◽  
pp. 328-329
Author(s):  
E. A. Kenik ◽  
J. Bentley
Keyword(s):  
Thin Foil ◽  
Electron Excitation ◽  
Simple Approach ◽  
Foil Thickness ◽  
X Rays ◽  
X Ray ◽  
Hole Spectrum ◽  
Illumination System ◽  
Thin Foils ◽  
Intensity Ratios

Cliff and Lorimer (1) have proposed a simple approach to thin foil x-ray analy sis based on the ratio of x-ray peak intensities. However, there are several experimental pitfalls which must be recognized in obtaining the desired x-ray intensities. Undesirable x-ray induced fluorescence of the specimen can result from various mechanisms and leads to x-ray intensities not characteristic of electron excitation and further results in incorrect intensity ratios.In measuring the x-ray intensity ratio for NiAl as a function of foil thickness, Zaluzec and Fraser (2) found the ratio was not constant for thicknesses where absorption could be neglected. They demonstrated that this effect originated from x-ray induced fluorescence by blocking the beam with lead foil. The primary x-rays arise in the illumination system and result in varying intensity ratios and a finite x-ray spectrum even when the specimen is not intercepting the electron beam, an ‘in-hole’ spectrum. We have developed a second technique for detecting x-ray induced fluorescence based on the magnitude of the ‘in-hole’ spectrum with different filament emission currents and condenser apertures.

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