999 resultados para Dirac states


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Electron-impact ionization cross sections are calculated for the ground and metastable states of C+. Com- parisons between perturbative distorted-wave and nonperturbative time-dependent close-coupling calculations find reductions in the peak direct ionization cross sections due to electron coupling effects of approximately 5% for ground state C+ and approximately 15% for metastable state C+. Fairly small excitation-autoionization contributions are found for ground state C+, while larger excitation-autoionization contributions are found for metastable state C+. Comparisons between perturbative distorted-wave and nonperturbative R-matrix with pseudostates calculations find reductions in the peak total ionization cross sections due to electron coupling effects of approximately 15–20 % for ground state C+ and approximately 25–35 % for metastable state C+. Finally, comparisons between theory and experiment find that present and previous C+ crossed-beam measure- ments are in excellent agreement with ground state nonperturbative R-matrix with pseudostates calculations for total ionization cross sections. Combined with previous non-perturbative calculations for C, C2+, and C3+, accurate ionization cross sections and rate coefficients are now available for the ground and metastable states of all carbon ion stages.

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Absolute Se photoionization cross-section measurements and Dirac-Coulomb R -matrix calculations are reported for the photon energy range 18.0 eV – 31.0 eV, which spans the ionization thresholds of the 4 S 0 3/2 ground state and the low-lying 2 D 0 3/2,5/2 and 2 P 0 1/2,3/2 metastable states. The determination of the photoionization and recombination properties of n -capture element ions is motivated by their astrophysical detection and the importance of their elemental abundances in testing theories of nucleosynthesis and stellar structure.

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To test the validity of classical trajectory and perturbative quantal methods for electron-impact ionization of H-like ions from excited states, we have performed advanced close-coupling calculations of ionization from excited states in H, Li 2+ and B 4+ using the R -matrix with pseudo states and the time-dependent close-coupling methods. Comparisons with our classical trajectory Monte Carlo (CTMC) and distorted-wave (DW) calculations show that the CTMC method is more accurate than the DW method for H, but does not improve with n and grows substantially worse with Z , while the DW method improves with Z and grows worse with n .

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The total cross sections for photodetachment of the metastable 1s 22p3 4S° and 1s2s2p3 6S° excited bound states of the negative ion of beryllium are presented for a range of initial photon energies across and beyond the 1s detachment threshold. A multichannel close-coupling R-matrix approximation is used to compute the cross sections, with sophisticated configuration-interaction wavefunctions being used to represent the initial and final states. At present there are no other theoretical or experimental data available with which to compare the cross sections for these two photodetachment processes.

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Genetically engineered (GE) crops are subject to regulatory oversight to ensure their safety for humans and the environment. Their approval in the European Union (EU) starts with an application in a given Member State followed by a scientific step (risk assessment), and ends with a political decision-making step (risk management); and in the United States (US) it starts with a scientific (field trial) step and ends with a ‘bureaucratic’ decision-making step. We investigated trends for the time taken for these steps and the overall time taken for approving GE crops in the US and the EU (traders in these commodities). Results show that from 1996-2015 the overall time trend for approval in the EU decreased and then flattened off, with an overall mean completion-time of 1,763 days. In the US in 1998 there was a break in the trend of the overall approval time: Initially, from 1988 until 1997 the trend decreased with a mean approval time of 1,321 days; from 1998-2015, the trend almost stagnated with a mean approval time of 2,467 days.

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This chapter focuses on the growing tendency of international human rights law to require states to protect the rights of non-nationals who are in the state unlawfully and of nationals and non-nationals who are outside the state, especially when any of these people are involved in terrorist or counter-terrorist activity. It reviews these additional obligations within a European context, focusing on EU law and the law of the European Convention on Human Rights and drawing on the case law of UK courts. Part 1 considers when a European state must grant asylum to alleged terrorists on the basis that otherwise they would suffer human rights abuses in the state from which they are fleeing. Part 2 examines whether, outside of asylum claims, a European state must not deport or extradite an alleged terrorist because he or she might suffer an abuse of human rights in the receiving state. Part 3 looks at whether a European state whose security forces are engaged in counter-terrorism activities abroad is obliged to protect the human rights of the individuals serving in those forces and/or the human rights of the alleged terrorists they are confronting. While welcoming the extension of state responsibility, the chapter notes that it is occurring in a way which introduces three aspects of relativity into the protection of human rights. First, European law protects only some human rights extra-territorially. Second, it protects those rights only when there is ‘a real risk’ of their being violated. Third, sometimes it protects those rights only when there is a real risk of their being violated ‘flagrantly’.

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Over the last 36 years, the relationship with the Portuguese state-owned enterprises registered several dynamics: nationalizations, privatizations and corporatization of public services. However, until now the State Business Sector from a national accounts perspective was never analyzed. Based on data collected and compiled for the first time at Statistics Portugal, this PhD thesis aims to test, analyzing in eight dimensions, whether the weight of the State Business Sector increased and if it contributed positively to the Portuguese economy, from 2006 to 2010. In addition to this analysis, an overview of the economic theory of state intervention in the economy, the paradigm changes of public policy in the international context, the evolution of the Portuguese State Business Sector since 1974, accompanied with a business and national accounting perspective between 2006 and 2010, are also presented. The results allow us to conclude that, in general, the weight of the State Business Sector in the Portuguese economy increased and had a tendency of a positive contribution to its economic growth. The State Business Sector also contributed positively to the nominal labour productivity (although with a decreasing trend of contribution to growth over the period under review) and the profitability of the non-financial corporations sector (although impairing the overall ratio of this sector). Nonetheless, the State Business Sector contributed negatively to the fairness in compensation of employees (although with an improvement trend) and to the competitiveness of labour cost, investment and sectorial sustainability of the Portuguese economy (reinforced by a falling trend). The results also suggest that the State Business Sector had an economic behaviour closer to a welfare maximizing model than to a profit maximizing model. This distinct performance with respect to the institutional sector in which is included, highlights the need to study and reassess the relationship of the state with public corporations, in light of agency theory using micro-data. Lastly, contributions to improve the economic performance of the State Business Sector and future prospects of evolution are presented.

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This document contains a speech by John L. McLaurin, representative of South Carolina. Sections of the speech include: sectionalism exposed, the bill might have been defeated, the south plundered of its rights, not a protectionist, fraudulent demands of New England, Hon. Randolph Tucker, Hon. W.R. Morrison, and Hon. R.Q. Mills strangers to the doctrine in 1882, a tariff for revenue against the doctrine of free raw material, don’t want Cleveland’s interpretation, contest of schedules, and my remedy.

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This document contains a speech by John L. McLaurin of South Carolina presented in the Senate of the United States. Sections of the speech include: sectionalism the cause, conditions in South Carolina, the federal administration in South Carolina, should not array class against class, freedom of thought and speech, the issues, under caucus dictation the Senate no longer a deliberative body, the beginning of the fight, matter of arraying class against class, freedom of thought and speech, and issues.

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This document is an account of a convention of South Carolina state representatives following the drafting of the Declaration of Independence. There were three parties involved in the convention and the account is based on the notes of Mr. Luther Martin who attended as well Mr. Justice Yates’ account. The first party wished to abolish all state governments and have one uniform monarchical government for the continent that would be restricted and limited. The second party did not wish to abolish state governments to give their own state some importance. The third party was advocating for a federal government in conjunction with state government. This document is an account of the convention.

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The speech is a response by Hon. James H. Hammond as to whether or not the territorial governments established by Congress have the power to define and declare what shall be and what shall not be property within the territorial boundaries. The speech goes on to discuss colonists who went to newly purchased territory and claimed land as their own. He argues whether or not these people have sovereignty of the land over the government.

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This speech is to address the statement that Mr. McLaurin has been excluded from the caucuses of his party and thus that he will be without assignment on any committee. He goes on to explain his exclusion and defend his views that led to his exclusion.

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The speech addresses the question, how can the union be preserved? He goes on to explain the threats to the union and give suggestions for how the threats can be handled.

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This speech was given when the United States Senate was considering a bill to authorize the free coinage of the standard silver dollar and to restore its legal tender character. Mr. Bayard argues against the bill in this speech. He is interrupted during his speech multiple times and questioned about his points.