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Aufsatz
Femtosecond real-time probing of reactions. 13. Multiphoton dynamics of IHgI
(1993)
Real-time studies of the dynamics were performed on the reaction of HgI_2 in a molecular beam. Excitation was by either one or multi pump photons (311 nm), leading to two separate sets of dynamics, each of which could be investigated by a time-delayed probe laser (622 nm) that ionized the parent molecule and the fragments by REMPI processes. These dynamics were distinguished by combining the information from transients taken at each mass (HgI_2, HgI, I_2, Hg, and I) with the results of pump (and probe) power dependence ...
Aufsatz
High laser field effects in multiphoton ionization of Na_2
(1992)
Femtosecond pump/probe multiphoton ionization experiments on Na_2 molecules are performed. The dependence of the total Na^+_2 ion signal on the delay time and the intensity of the femtosecond laser pulses is studied in detail. It is observed that molecular vibrational wavepacket motion in different electronic states dominates the time dependence of the ion signal. For higher laser intensities the relative contributions from the A ^1 \summe^+_u and the 2 ^1 \produkt__g states change dramatically, indicating the ...
Aufsatz
Income and price elasticities of animal food demand and welfare in Indonesian urban: an application of the LA-AIDS
(2022-12-30)
Protein consumption can be a measure of the welfare of society. Developed countries consume more protein than developing countries. This study analyzes the effect of rising prices and income on demand and welfare in urban Indonesia. The research data use the 2018 Household National Socio-Economic Survey (Susenas) data in household consumption and expenditure data collected by the Central Statistics Agency (BPS). The number of samples is 133,873 households. The demand systems approach uses the Almost Ideal Demand ...
Aufsatz
Exploring inclusiveness of vulnerable and marginalized people in the cassava value chain in the Lake Region, Kenya
(2023-03-21)
Vulnerable and marginalised groups (VMGs) who comprise widows, orphans, people living with disability and HIV, have not been given sufficient attention in agriculture in sub-Saharan Africa (SSA) by policy makers, development partners, research, and extension, yet they comprise nearly one-quarter of all smallholder farmers. This study explored inclusion of VMGs in cassava value chain in the Lake Region of Kenya. Formal survey, focus group discussions (FGD), and key informant interviews (KIIs) were used to collect data ...
Aufsatz
Sustainable Eating Futures: A Case Study in Saudi Arabia
(2022-10-25)
Food systems are central to human societies. Developing sustainable, nutritious, and healthy food systems will be crucial to accomplishing sustainable development goals. The multifarious politics underlying food production, distributions as well as consumption are often ignored. The present paper analyses different factors affecting food consumption in the local population of Saudi Arabia and relates them to the supply chain. Different futuristic scenarios are discussed to develop sustainable food consumption practices ...
Aufsatz
Mental rotation and the motor system: Embodiment head over heels
(2013-12-13)
We examined whether body parts attached to abstract stimuli automatically force embodiment in a mental rotation task. In Experiment 1, standard cube combinations reflecting a human pose were added with (1) body parts on anatomically possible locations, (2) body parts on anatomically impossible locations, (3) colored end cubes, and (4) simple end cubes. Participants (N = 30) had to decide whether two simultaneously presented stimuli, rotated in the picture plane, were identical or not. They were fastest and made less ...
Aufsatz
Unrestricted hartree-fock calculation of the ionization potential of small Hg_n clusters
(1993)
The ionization potential of small Hg_n clusters has been calculated. For the first time good agreement with experimental results has been obtained. It is shown that interatomic Coulomb interactions are important. The energy of Hg_n^+ is calculated using the unrestricted inhomogeneous Hartree-Fock approximation. As a consequence of a change in the charge distribution in Hg_n^+ , we obtain an abrupt change in the slope of the ionization potential at the critical cluster size n_cr ~ 14. The presented results are expected ...
Aufsatz
Calculation of the electronic properties of neutral and ionized divalent-metal clusters
(1993)
The electronic properties of neutral and ionized divalent-metal clusters have been studied using a microscopic theory, which takes into account the interplay between van der Waals (vdW) and covalent bonding in the neutral clusters, and the competition between hole delocalization and polarization energy in the ionized clusters. By calculating the ground-state energies of neutral and ionized. Hg_n clusters, we determine the size dependence of the bond character and the ionization potential I_p(n). For neutral Hg_n ...
Aufsatz
On the transition from localized to delocalized electronic states in divalent-metal clusters
(1991)
The transition from van der Waals to covalent bonding, which is expected to occur in divalent-metal clusters with increasing cluster size, is discussed. We propose a model which takes into account, within the same electronic theory, the three main competing contributions, namely the kinetic energy of the electrons, the Coulomb interactions between electrons, and the s \gdw p intraatomic transitions responsible for van der Waals like bonding. The model is solved by taking into account electron correlations using a ...
Aufsatz
On the localization of electrons and holes in Hg_n and rare-gas clusters
(1994)
We have used a microscopic theory to study the size dependence of the degree of localization of the valence electrons and holes in neutral an ionized rare-gas and Hg_n clusters. We discuss under which circumstances localization of the electrons and holes is favoured. We have calculated the ionization potential of Xe_n, Kr_n and small Hg_n clusters. Good agreement with experiments is obtained. We have also determined the dependence of the ionization potential on cluster structure.