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"Diffusion in solids at moderate temperatures is a well-known phenomenon. However, direct experimental evidence about the responsible atomic-scale mechanisms has been scarce, due to difficulties in probing the relevant length- and time-scales. The present thesis deals with the application of X-ray Photon Correlation Spectroscopy (XPCS) for answering such questions. This is an established method for the study of slow dynamics on length-scales of a few nanometres. The scattered intensity in the diffuse regime, i.e. corresponding to atomic distances, is very low, however, and so it has so far been considered impossible to use XPCS for this problem.Threefold progress is reported in this work. It proposes a number of systems selected for high diffuse intensity, it optimizes the photon detection and data evaluation procedures, and it establishes theoretical models for interpretating the results. Together these advances allowed the first successful atomic-scale XPCS experiment, which elucidated the role of preferred configurations for atomic jumps in a copper-gold alloy. "

"This book presents the various types of coherent states introduced and studied in the physics and mathematics literature and describes their properties together with application to quantum physics problems. It is intended to serve as a compendium on coherent states and their applications for physicists and mathematicians, stretching from the basic mathematical structures of generalized coherent states in the sense of Perelomov via the semiclassical evolution of coherent states to various specific examples of coherent states (hydrogen atom, quantum oscillator, ...)."

"The book is a comprehensive edition which considers the interactions of atoms, ions and molecules with charged particles, photons and laser fields and reflects the present understanding of atomic processes such as electron capture, target and projectile ionisation, photoabsorption and others occurring in most of laboratory and astrophysical plasma sources including many-photon and many-electron processes. "

"ABSTRAKPencemaran logam berat terhadap alam lingkungan merupakan suatu proses yang erat hubungannya dengan penggunaan logam berat oleh manusia yang tidak memperhatikan keselamatan lingkungan. Kontaminasi dari timbal (Pb), tembaga (Cu), dan kadmium (Cd) pada sayuran seperti selada, bayam merah, dan genjer akan menimbulkan masalah kesehatan apabila melebihi batas cemaran yang diperbolehkan. Penelitian ini dilakukan untuk mengetahui kadar logam pada sampel dari lahan kebun sayur yang terletak di Jalan Pramuka Jakarta Pusat. Sampel dicuci bersih terlebih dahulu kemudian dikeringkan dengan oven pada suhu 80o C selama 4 jam, setelah kering kemudian diblender menjadi serbuk. Sampel didestruksi denganasam nitrat pekat menggunakan alat microwave digestion system pada suhu 180oC selama 25 menit, lalu sampel dianalisis dengan spektrofotometer serapan atom (SSA). Hasil kadar rata-rata timbal dalam batang dan daun genjer, selada, dan bayam merah dalam sampel antara 0,12±0,05 sampai 0,63±0,03 mg/kg. Kadar rata-rata kadmium dalam batang dan daun genjer, selada, dan bayam merah dalam sampel antara 0,001±0,006 sampai 0,009±0,001 mg/kg. Kadar rata-rata tembaga dalam batang dan daun genjer, selada, dan bayam merah dalam sampel antara 0,17±0,01 sampai 0,55±0,005mg/kg. Pada hasil analisis kadar cemaran timbal pada batang genjer melewati batas kadar aman.

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ABSTRACTHeavy metal contamination on natural environment is a process that closely related to human?s using of heavy metal without paying attention to environmental safety. Contamination of lead (Pb), copper (Cu) and cadmium (Cd) in vegetables like lettuce, red spinach, and genjer will cause health problem if they exceed safety limit of contamination. This research was conducted to determine metal content in sampel (lettuce, red spinach, and genjer) from farm that located in Jalan Pramuka Jakarta Pusat. Samples were first washed and then dried in an oven at a temperature of 80o C for 4 hours, after ward blended into powder. Destruction of samples were done by microwave digestion system at 180 o C for 25 minute with using concentrated nitric acid. After destruction process, samples

were analyzed with atomic absorption spectrophotometry. The result showed average levels of lead in stems and leaf of genjer, lettuce, red spinach were between 0.12±0.05 to 0.63±0.03 mg/kg. The average levels of cadmium in stems and leaves of genjer, lettuce, red spinach were between 0.001±0.006 to 0.009±0.001 mg/kg. The average copper content in stems and leaves of genjer, lettuce, red spinach were between 0.17±0.01 to 0.55±0.005mg/kg. The result also showed that the level of lead contamination in the trunk of genjer over the safe

limit for humans comsumption."