13 research outputs found
Measured Stark widths of several spectral lines of Pb III
The Stark full widths at half of the maximal line intensity (FWHM, ω) have been measured for 25 spectrallines of PbIII (15 measured for the first time) arising from the 5d106s8s, 5d106s7p, 5d106s5f and 5d106s5g electronic configurations, in a lead plasma produced by ablation with a Nd:YAG laser. The optical emission spectroscopy from a laser-induced plasma generated by a 10 640 Å radiation, with an irradiance of 2 × 1010 W cm− 2 on a lead target (99.99% purity) in an atmosphere of argon was analysed in the wavelength interval between 2000 and 7000 Å. The broadening parameters were obtained with the target placed in argon atmosphere at 6 Torr and 400 ns after each laser light pulse, which provides appropriate measurement conditions. A Boltzmann plot was used to obtain the plasma temperature (21,400 K) and published values of the Starkwidths in Pb I, Pb II and PbIII to obtain the electron number density (7 × 1016 cm− 3); with these values, the plasma composition was determined by means of the Saha equation. Local Thermodynamic Equilibrium (LTE) conditions and plasma homogeneity has been checked. Special attention was dedicated to the possible self-absorption of the different transitions. Comparison of the new results with recent available data is also presented
Transition probabilities of 30 Pb II lines of spectrum obtained by emission of a laser-produced plasma
Transition probabilities have been determined for 30 lines of Pb II by measuring the intensities of the emission lines of a laser-produced plasma (LPP) of Pb in an atmosphere of Ar. The plasma has been seen to contain local thermodynamic equilibrium (LTE) and homogeneity; the plasma studied has a temperature of 11 500 K and an electron density of 1016 cm−3. The experimental results obtained during this study have been compared with the experimental and theoretical values given by other authors
A spectroscopic study of the plasma generated in a thallium arc. Transition probabilities for several lines of Tl I
The optical emission spectra (2000–15 000) A of a plasma produced an a Tl arc lamp have been recorded and analysed; using the series nd 2D3/2`5/2 → 6p 2P Q3/2 and ns 2SL/2 → 6p 2P Q3/2 we have obtained that the electron density is of the order of 10L4 cm−3 and the excitation temperature is (2880 ± 50) K. Relative transition probabilities for 26 lines from excited levels near the ionization limit of Tl I have been determined from line intensities
A Spectroscopic study of laser-induced Tin-Lead plasma: transition probabilities for spectral lines of Sn I
In this paper, we present transition probabilities for 97 spectral lines of Sn I, corresponding to transitions n(n = 6,7,8)s → 5p2, n(n = 5,6,7)d → 5p2, 5p3 → 5p2, n(n = 7)p → 6s, determined by measuring the intensities of the emission lines of a Laser-induced breakdown (emission) spectrometry (LIBS). The optical emission spectroscopy from a laser-induced plasma generated by a 10 640 Å radiation, with an irradiance of 1.4 × 1010 Wcm− 2 on an Sn–Pb alloy (an Sn content of approximately 20%), in vacuum, was recorded at 0.8 µs, and analysed between 1900 and 7000 Å. The population-level distribution and corresponding temperature were obtained using Boltzmann plots. The electron density of the plasma was determined using well-known Stark broadening parameters of spectral lines. The plasma under study had an electron temperature of 13,200 K and an electron number density of 2 × 1016 cm− 3. The experimental relative transition probabilities were put on an absolute scale using the branching ratio method to calculate Sn I multiplet transition probabilities from available radiative lifetime data of their upper states and plotting the Sn I emission spectrum lines on a Boltzmann plot assuming local thermodynamic equilibrium (LTE) to be valid and following Boltzmann's law. The LTE conditions and plasma homogeneity have been checked. Special attention was paid to the possible self-absorption of the different transitions. The experimental results obtained have been compared with the experimental values given by other authors
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Tanzania: Lessons in Building Linkages for Competitive and Responsible Entrepreneurship
Increasing economic opportunity, productivity, and growth offers one of our best hopes for reducing poverty. As the Organisation for Economic Co-operation and Development's Development Assistance Committee (OECD DAC) has commented, however, 'Increasing economic growth rates is essential - but it is not enough. The quality of growth - its sustainability, composition and equity - is equally important.' Crucial elements of reducing poverty are creating jobs, income-generating opportunities, and livelihoods for the poor. In particular, growth must encompass improving the access of small enterprises to finance, skills, technology, information, sound business practices, legal rights, and markets.
In Tanzania, as in many developing countries, achieving the goal of reducing poverty requires effective partnerships and intermediaries that are able to address the market failures, governance gaps, and institutional constraints that currently exclude or disadvantage most small entrepreneurs from accessing these public goods and business opportunities. Such partnerships are also essential in helping small enterprises upgrade and integrate into broader production networks and value chains, a growth that in turn is crucial for raising productivity and employment levels.
These partnerships include brokerage mechanisms, business linkage initiatives, hybrid commercial and social business models, innovative financing instruments, enhanced enterprise support services, and new types of alliances among companies, trade associations, governments, donors, academic institutions, and non-governmental organisations. They offer great potential for promoting enterprise development, reducing poverty, and helping to spread more competitive and responsible business practices along the value chain between large- and small-scale firms. Yet such partnerships are relatively new and untested. They are currently few in number and disconnected from each other at the global and national levels. Because of this, they are limited in scale and effectiveness.Version of Recor
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The Global Road Safety Partnership and Lessons in Multisectoral Collaboration
"The world is witnessing an unprecedented increase in demand for motorized vehicles, particularly in rapidly developing economies such as China and India. Per capita GDP growth creates a demand for faster modes of passenger and freight transport.
Additionally, increasing motorized mobility fosters a feedback loop in which the need for better roads propels expansion of infrastructure assets, which in turn drives GDPS While motorization and enhanced mobility have positive impacts on individual lives and national GDP, without appropriate strategies to improve road safety, road accidents and deaths are becoming an ever-increasing problem.
According to a World Health Organization (WHO)/World Bank jointly produced report, road traffic injuries were the 11th leading cause of death in 2002. However, without appropriate action, the WHO estimates that by 2020 they will outpace AIDS, malaria, and war as the world's third largest public health challenge after ischemic heart disease and unipolar major depression. In addition to road deaths, it is estimated that between 30 and 45 injuries occur for every road death, many involving permanent disability and high lifetime costs of ongoing care, support, and lost earnings. Developing countries are, and will continue to be, the hardest hit. Road accident injury and death also pose a significant monetary cost. The most productive age group (15-44 years), often in the lowest income sector, accounts for the highest injury and death rate. The combined costs of health care, loss of income, and funeral costs can have a ruinous effect on both households and communities.
At a macroeconomic level, the WHO estimates that road traffic injuries cost low-and middle-income countries between 1% and 2% of their gross national product and carry approximately a US$65 billion price tag in developing countries, outstripping the amount these nations receive in development assistance.
A link between increased demand for vehicles and road accidents has been noted at the early stages of motorization in developed countries. This generally peaks and tends to level off. The increased injury trend levels off, however, as a result of government regulation, enforcement, safer vehicles, better infrastructure, a culture of safer road use behavior, and education. Developing countries are now going through similar cycles, but due to population size and other factors, the fatality burden remains substantial. A key challenge for governments and other actors is to share and implement the public policy lessons, technologies, and institutional innovations that have underpinned safety improvements in developed countries to attenuate the evolving trends in developing countries rapidly and proactively."Version of Recor
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Business as a Partner in Tackling Micronutrient Deficiency: Lessons in Multisector Partnership
"Sustainable and equitable international development is predicated on individuals who are able to live long, healthy lives, be innovative, work, and contribute to society. These basic human traits are contingent on proper nutrition, particularly during childhood, to foster normal growth and healthy development.
Micronutrient deficiency - the lack of proper vitamins and minerals in diet - is a hidden epidemic that leads to low birth weight, impaired cognitive development, impaired immunity, and compromised life expectancy. These problems have a disastrous effect on human capital, which is a key to improving both individual lives and to fostering the growth of national economies.
Low birth weight and stunted growth can result in diminished strength and ability to work, potentially resulting in lower productivity and income.
Impaired cognitive development leads to learning problems, and the inability of children to learn in school has a significant effect on their wages 20 years after schooling? These deficiencies in turn have links to broader economic growth and development. "Because education level ... is strongly linked to national economic growth, the loss of individual creative potential directly affects the long-term aggregate development trajectory of developing countries." Micronutrient deficiency in childhood also has long-term impacts on individuals ability to fight disease, which has serious consequences for family life, earning capacity, and macroeconomic growth."Version of Recor
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Viet Nam: Lessons in Building Linkages for Competitive and Responsible Entrepreneurship
Increasing economic opportunity, productivity, and growth offers one of our best hopes for reducing poverty. As the Organisation for Economic Co-operation and Development's Assistance Committee (OECD DAC) has commented, however, 'Increasing economic growth rates is essential - but it is not enough. The quality of growth - its sustainability, composition and equity — is equally important.' Crucial elements of poverty reduction are creating jobs, income-generating opportunities, and livelihoods for the poor. In particular, growth must encompass improving the access of small enterprises to finance, skills, technology, information, sound business practices, legal rights, and markets.
In Viet Nam, as in many developing countries, achieving the goal of reducing poverty requires effective partnerships and intermediaries that are able to address the market failures, governance gaps, and institutional constraints that currently exclude or disadvantage most small entrepreneurs from accessing these public goods and business opportunities. Such partnerships are also essential in helping small enterprises upgrade and integrate into broader production networks and value chains, which in turn is crucial for raising productivity and employment levels.
These partnerships include brokerage mechanisms, business linkage initiatives, hybrid commercial and social business models, innovative financing instruments, enhanced enterprise support services, and new types of alliances among companies, trade associations, governments, donors, academic institutions, and non-governmental organisations. They offer great potential for promoting enterprise development, reducing poverty, and helping to spread more competitive and responsible business practices along the value chain between large- and small-scale firms. Yet such partnerships are relatively new and untested. They are currently few in number and disconnected from each other at the global and national levels. Because of this, they are limited in scale and effectiveness.Version of Recor
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Social Risk as Strategic Risk
A series of spectacular corporate governance and ethical compliance failures as well as the Sarbanes-Oxley Act and other regulatory responses have focused increasing attention on governance and compliance risks. Equally serious are the long-term ""strategic risks,"" such as disruptive innovation or failure to predict shifts in consumer preferences, that companies face. Strategic risks are characterized by complex origins and equally complex, far-reaching impacts.
They have the potential to jeopardize both current earnings and growth prospects. As a result, strategic risks require forward-looking risk management approaches that are integrated across the enterprise and linked with strategic planning.
Social and environmental issues are emerging as troublesome sources of strategic risk. These issues can present risks directly, by presenting direct operating constraints, or indirectly— for example, by seeding "social risk," or challenges by stakeholders to companies' business practices due to real or perceived impacts on social or environmental issues.
As Exhibit ES-1 illustrates, the emergence of social risk is characterized by four components in combination: an issue, a stakeholder or group of stakeholders, a negative perception about the company, and the means to do damage.Version of Recor
