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Light waves allow preferred bond breaking in symmetric molecules -- ScienceDaily

Light waves allow preferred bond breaking in symmetric molecules Date:

May 8, 2014

Source: Max Planck Institute of Quantum Optics Chemical bonds between carbon and hydrogen atoms are amongst the strongest in nature and their selective breaking, in particular in symmetric molecules, is of interest to chemical synthesis and the development of new biologically active molecules. An international team of scientists has now demonstrated that ultrashort light pulses with perfectly controlled waveforms can selectively break C-H bonds in acetylene ions. The researchers demonstrated that a suitable choice of the laserpulse waveform leads to breaking of the C-H bond on the left (or right) side of the symmetric H-C≡C-H molecule. The scientists propose that their results can be understood by a new quantum control mechanism based on light induced vibration.

Illustration of the directional proton emission in acetylene with a specific laser waveform. The superposition of vibrational modes, which are responsible for the selective bond breaking, results from a combination of laser excitation of the antisymmetric CH stretching mode and excitation of the symmetric CH stretching mode through ionization steps. The ionization steps are indicated by a change in colour from green (neutral) over yellow (cation) to orange (dication).

Credit: Graphic Christian Hack enberger, MPQ, Hydrocarbons play an Attosecond Physics division important role in organic chemistry, combustion, and catalysis. Selective breaking of C-H-bonds, can further enable novel synthesis of molecular species with new functionalities and applications in medicine. Until now a method for breaking C-H bonds selectively in symmetric hydrocarbons did not exist. Prof. Ali Alnaser (American University of Sharjah, UAE), who spent his sabbatical in the division of Prof. Ferenc Krausz at the Max Planck Institute of Quantum Optics (MPQ) as part of the collaboration between MPQ, the King Saud University (KSU), and the Ludwig-Maximilians-Universität Munich (LMU), and a team of physicists led by Prof. Matthias Kling (LMU) used ultrashort laser pulses to solve this problem. An important ingredient in making the experiments successful was the use of a high repetition rate laser system with ten thousand pulses per second in the group of Prof. Ulf Kleineberg (LMU), whereby the measuring times could be reduced compared to so far available systems. Mechanistic insight into how the laser light interacts with the molecules is provided by a theoretical model developed in the group of Prof. Regina de Vivie-Riedle (LMU). For their experimental studies, the researchers used acetylene (C2H2): In this molecule the two carbon atoms are strongly bound by three electron pairs, while the hydrogen atoms symmetrically terminate the linear molecule on both ends. The scientists exposed a supersonic jet of C2H2 molecules inside a so called reaction microscope to ultrashort laser pulses with duration of only 4 fs (1 fs = 10-15 seconds). These pulses, generated in the Laboratory for Attosecond Physics of Prof. Ferenc Krausz (MPQ, LMU), have infrared wavelengths and consist of only a few cycles. The waveform http://www.sciencedaily.com/releases/2014/05/140508095452.htm?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+sciencedaily+%28Lat…

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Light waves allow preferred bond breaking in symmetric molecules -- ScienceDaily

of the light waves was precisely measured for each laser shot interacting with the molecules. "As a result of the interaction with the light wave, the molecule fragments after its double ionization into a positively charged C2H+ ion and a proton, which are both detected with the reaction microscope.," says Prof. Ali Alnaser. Since acetylene is a symmetric molecule, the C-H bonds on both sides of the molecule typically break with equal probability. In their experiment however, the scientists found that the laser waveform provides a means to increase the probability that the left versus the right C-H bond breaks and vice versa. Quantum dynamical simulations show the nature of the laser-molecule interaction. "The already known scheme, where molecular reactions are controlled by electron dynamics prepared with the light waveform via laser-induced coupling of electronic states, does not work in this case. We discovered a new quantum control pathway.," Prof. de Vivie-Riedle explains. According to her new model, the few cycle laser pulse initially excites a subset of vibrations of the molecule that are laser-active. One of these vibrations is the anti-symmetric stretching mode, where one CH bond is elongated while the other is shortened. When the laser pulse reaches its peak electric field, it removes an electron from the triplebond of the CC group (the molecule ionizes). By this process additionally laser-inactive vibrational modes are populated. Among those modes is the symmetric CH stretching mode, where both H atoms move synchronously towards or away from the CC group. In the remainder of the laser pulse, the freed electron is accelerated back onto the molecular cation, removes a second electron and creates the acetylene dication, which rapidly dissociates into the proton and the C2H+ ion that are observed in the experiment. "Independent excitation of vibrations of the molecule is insufficient to explain the experimental results. A prerequisite for the observed control is a quantum effect: the superposition of the symmetric and anti-symmetric stretching modes. As a consequence of that interference, a situation can be created where only one CH bond vibrates and the other one remains frozen.," explains Prof de Vivie-Riedle. "This type of shaking of the molecule leads to breaking of a particular CH bond. The laser waveform controls the direction into which the vibrational wave packet, which results from the superposition of the vibrational modes, moves once it is created on the acetylene dication.," adds Prof. Matthias Kling. The researchers see the results of their studies as a proof-of-principle for a new quantum control mechanism. "The laser waveform control mechanism is very general and we foresee that it may be applied to other, more complex molecular processes.," says Prof. Ali Alnaser, who wants to continue research into this direction. He adds: "While we have excited the vibrations non-resonantly in our study, higher degrees of control can be reached with resonant excitation using ultrashort laser pulses in the mid-infrared. Such laser systems are currently being developed and pave the way to exploit the full potential of the new control scheme." Story Source: The above story is based on materials provided by Max Planck Institute of Quantum Optics. Note: Materials may be edited for content and length. Journal Reference: 1. A.S. Alnaser, M. KĂźbel, R. Siemering, B. Bergues, Nora G Kling, K.J. Betsch, Y. Deng, J. Schmidt, Z.A. Alahmed, A.M. Azzeer, J. Ullrich, I. Ben-Itzhak, R. Moshammer, U. Kleineberg, F. Krausz, R. de Vivie-Riedle, M.F. Kling. Subfemtosecond steering of hydrocarbon deprotonation through superposition of vibrational modes. Nature Communications, 2014; 5 DOI: 10.1038/ncomms4800 Cite This Page: MLA

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Max Planck Institute of Quantum Optics. "Light waves allow preferred bond breaking in symmetric molecules." ScienceDaily. ScienceDaily, 8 May 2014. <www.sciencedaily.com/releases/2014/05/140508095452.htm>.

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Light waves allow preferred bond breaking in symmetric molecules dailynewsen.com /science/light-waves-allow-preferred-bond-breaking-in-symmetric-molecules-h2488778.html An international team of scientists discovered a new quantum manage mechanism to selectively shake and break C-H bonds in symmetric hydrocarbon molecules with the waveform of femtosecond laser pulses. Chemical bonds between carbon and hydrogen atoms are amongst the strongest in nature and their selective breaking, in distinct in symmetric molecules, is of interest to chemical synthesis and the development of new biologically active molecules. An international group of scientists has now demonstrated that ultrashort light pulses with perfectly controlled waveforms can selectively break C-H bonds in acetylene ions. The researchers demonstrated that a appropriate choice of the laser-pulse waveform leads to breaking of the C-H bond on the left (or correct) side of the symmetric H-Câ&#x2030;ĄC-H molecule. The scientists propose that their outcomes can be understood by a new quantum control mechanism based on light induced vibration. Hydrocarbons play an important part in organic chemistry, combustion, and catalysis. Selective breaking of C-Hbonds, can further enable novel synthesis of molecular species with new functionalities and applications in medicine. Till now a method for breaking C-H bonds selectively in symmetric hydrocarbons did not exist. Prof. Ali Alnaser (American University of Sharjah, UAE), who spent his sabbatical in the division of Prof. Ferenc Krausz at the Max Planck Institute of Quantum Optics (MPQ) as element of the collaboration involving MPQ, the King Saud University (KSU), and the Ludwig-Maximilians-UniversitĂ¤t Munich (LMU), and a group of physicists led by Prof. Matthias Kling (LMU) utilised ultrashort laser pulses to solve this problem. An crucial ingredient in creating the experiments prosperous was the use of a high repetition price laser program with ten thousand pulses per second in the group of Prof. Ulf Kleineberg (LMU), whereby the measuring occasions could be lowered compared to so far accessible systems. Mechanistic insight into how the laser light interacts with the molecules is provided by a theoretical model developed in the group of Prof. Regina de Vivie-Riedle (LMU). For their experimental research, the researchers made use of acetylene (C2H2): In this molecule the two carbon atoms are strongly bound by three electron pairs, even though the hydrogen atoms symmetrically terminate the linear molecule on each ends. The scientists exposed a supersonic jet of C2H2 molecules inside a so known as reaction microscope to ultrashort laser pulses with duration of only four fs (1 fs = ten-15 seconds). These pulses, generated in the Laboratory for Attosecond Physics of Prof. Ferenc Krausz (MPQ, LMU), have infrared wavelengths and consist of only a few cycles. The waveform of the light waves was precisely measured (see figure) for every laser shot interacting with the molecules. "As a outcome of the interaction with the light wave, the molecule fragments after its double ionization into a positively charged C2H+ ion and a proton, which are both detected with the reaction microscope.", says Prof. Ali Alnaser. Considering that acetylene is a symmetric molecule, the C-H bonds on both sides of the molecule typically break with equal probability. In their experiment having said that, the scientists located that the laser waveform supplies a indicates to enhance the probability that the left versus the appropriate C-H bond breaks and vice versa (see figure 1). Quantum dynamical simulations show the nature of the laser-molecule interaction. "The currently identified scheme, where molecular reactions are controlled by electron dynamics ready with the light waveform by way of laserinduced coupling of electronic states, does not function in this case. We found a new quantum handle pathway.", Prof. de Vivie-Riedle explains. According to her new model, the few cycle laser pulse initially excites a subset of vibrations of the molecule that are laser-active. One particular of these vibrations is the anti-symmetric stretching mode, exactly where 1 CH bond is elongated whilst the other is shortened. When the laser pulse reaches its peak electric field, it removes an electron from the triple-bond of the CC group (the molecule ionizes). By this process additionally laser-inactive vibrational modes are populated. Amongst these modes is the symmetric CH stretching mode, where both H atoms move synchronously towards or away from the CC group. In the remainder of the laser https://www.printfriendly.com/print?url=http://www.dailynewsen.com/science/light-waves-allow-preferred-bond-breaking-in-symmetric-molecules-h2488778.html#

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pulse, the freed electron is accelerated back onto the molecular cation, removes a second electron and creates the acetylene dication, which quickly dissociates into the proton and the C2H+ ion that are observed in the experiment. "Independent excitation of vibrations of the molecule is insufficient to clarify the experimental final results. A prerequisite for the observed manage is a quantum impact: the superposition of the symmetric and anti-symmetric stretching modes. As a consequence of that interference, a circumstance can be designed where only one CH bond vibrates and the other one remains frozen.", explains Prof de Vivie-Riedle. "This kind of shaking of the molecule leads to breaking of a specific CH bond. The laser waveform controls the path into which the vibrational wave packet, which benefits from the superposition of the vibrational modes, moves when it is made on the acetylene dication.", adds Prof. Matthias Kling. The researchers see the results of their research as a proof-of-principle for a new quantum handle mechanism. "The laser waveform handle mechanism is really common and we foresee that it could be applied to other, extra complicated molecular processes.", says Prof. Ali Alnaser, who wants to continue study into this path. He adds: "Though we have excited the vibrations non-resonantly in our study, higher degrees of handle can be reached with resonant excitation making use of ultrashort laser pulses in the mid-infrared. Such laser systems are at the moment being developed and pave the way to exploit the complete potential of the new manage scheme." Read More: Phys

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Light waves allow preferred bond breaking in symmetric molecules

Figure 1: Illustration of the directional proton emission in acetylene with a specific laser waveform. The superposition of vibrational modes, which are responsible for the selective bond breaking, results from a combination of laser excitation of the anti-symmetric CH stretching mode and excitation of the symmetric CH stretching mode through ionization steps. The ionization steps are indicated by a change in colour from green (neutral) over yellow (cation) to orange (dication). Credit: Christian Hackenberger, MPQ, Attosecond Physics division

An international team of scientists discovered a new quantum control mechanism to selectively shake and break C-H bonds in symmetric hydrocarbon molecules with the waveform of femtosecond laser pulses. Chemical bonds between carbon and hydrogen atoms are amongst the strongest in nature and their selective breaking, in particular in symmetric molecules, is of interest to chemical synthesis and the development of new biologically active molecules. An international team of scientists has now demonstrated that ultrashort light pulses with perfectly controlled waveforms can selectively break C-H bonds in acetylene ions. The researchers demonstrated that a suitable choice of the laser-pulse waveform leads to breaking of the C-H bond on the left (or right) side of the symmetric H-C This document is subject to copyright. Apart from any fair dealing for the purpose of private study, research, no part may be reproduced without the written permission. The content is provided for information purposes only.

"Light waves allow preferred bond breaking in symmetric molecules." Phys.org. 9 May 2014. http://phys.org/news/2014-05-bond-symmetric-molecules.html

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5/29/2014

Lichtwellen ermöglichen bevorzugten Bindungsbruch in symmetrischen Molekülen

Lichtwellen ermöglichen bevorzugten Bindungsbruch in symmetrischen Molekülen 08.05.2014 nächste Meldung Ein internationales Wissenschaftlerteam hat eine Kontrollmöglichk eit gefunden, mit Hilfe von Lichtwellen eines Femtosek undenpulses selek tiv C-H Bindungen in symmetrischen Kohlenwasserstoffmolek ülen zum Schwingen und Brechen zu bringen.

Abbildung: Illustration der gerichteten Protonenemission aus Acetylen mit einer spezifischen Laserwellenform. Die kohärente Überlagerung der Schwingungen, die für den selektiven Bindungsbruch verantwortlich ist, entsteht durch eine Kombination aus der Laseranregung der asymmetrischen CH-Streckschwingung und der Anregung der symmetrischen CH-Streckschwingung in den Ionisationsschritten, die durch einen Farbwechsel von Grün (neutral) über Gelb (Kation) nach Orange (Dikation) angedeutet sind. (Foto: Christian Hackenberger, MPQ, Abt. Attosekundenphysik) Chemische Bindungen zwischen Kohlenstoff- und Wasserstoffatomen gehören zu den stärksten in der Natur. Für die chemische Synthese und die Entwicklung neuer biologisch-aktiver Moleküle ist es von großem Interesse, insbesondere in symmetrischen Molekülen, diese Bindungen selektiv zu brechen. Am Beispiel von Acetylen-Ionen hat jetzt ein internationales Wissenschaftlerteam gezeigt, dass dies mit ultrakurzen Lichtpulsen maßgeschneiderter Wellenform möglich ist. Die Forscher fanden heraus, dass sie durch Variation der Pulsform steuern können, welche der beiden C-H Bindungen des symmetrischen H-C≡C-H Moleküls bricht. In ihrer Veröffentlichung (Nature Communications, DOI:10.1038/ncomms4800) erklären sie ihre Ergebnisse mit einem neuen Quantenkontrollmechanismus, der auf der Kombination licht-induzierter Schwingungen beruht. ... mehr zu: » Acetylen » Bindung » Bindungsbruch » Elektron » LMU » Laserpuls » LudwigMaximilians-Universität » Max-Planck-Institut » Molekül » Nature » Quantenoptik » Schwingungen » Wechselwirkung » Wellenform

Kohlenwasserstoffe spielen eine bedeutende Rolle in der organischen Chemie, der Verbrennung und der Katalyse. Der selektive C-H Bindungsbruch könnte neue Perspektiven für die Synthese von Molekülen mit neuartigen Funktionalitäten und Anwendungen in der Medizin eröffnen. Bisher gab es vor allem für symmetrisch aufgebaute Moleküle kein Verfahren, das diesen Prozess ermöglicht hätte. Prof. Ali Alnaser (Amerikanische Universität Sharjah, VAE), der sein Forschungsfreisemester in der Abteilung von Prof. Ferenc Krausz am Max-PlanckInstitut für Quantenoptik (MPQ) im Rahmen einer Kollaboration zwischen dem MPQ, der King-Saud Universität (KSU) und der Ludwig-Maximilians-Universität (LMU) verbracht hat, konnte dieses Problem zusammen mit einem Physikerteam unter der Leitung von Prof. Matthias Kling (LMU) mit Hilfe ultrakurzer Lichtpulse lösen.

Mit entscheidend für den Erfolg der Experimente war die Erzeugung der Lichtpulse mit einer hohen Wiederholrate von zehntausend Pulsen pro Sekunde in der Gruppe von Prof. Ulf Kleineberg (LMU), wodurch die Messzeiten gegenüber bisher verfügbaren Systemen reduziert werden konnten. Theoretische Arbeiten aus der Gruppe von Prof. Regina de Vivie-Riedle (LMU) erklären im Einzelnen, welche Vorgänge in der Wechselwirkung von Laserpuls und Molekül zu diesem Effekt führen.

http://www.innovations-report.de/html/berichte/biowissenschaften-chemie/lichtwellen-ermoeglichen-bevorzugten-bindungsbruch-in-symmetrischen-molekuelen.wi…

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Lichtwellen ermöglichen bevorzugten Bindungsbruch in symmetrischen Molekülen

Für ihre experimentellen Untersuchungen verwendeten die Forscher Acetylen (C2H2): In diesem Molekül sind die zwei Kohlenstoffatome über drei Elektronenpaare sehr stark gebunden, während die Wasserstoffatome an den beiden Enden des linearen Moleküls sitzen. Auf einen Molekularstrahl von C2H2-Molekülen in einem sogenannten Reaktionsmikroskop schickten die Wissenschaftler eine Serie von ultrakurzen Pulsen weniger Schwingungszyklen mit einer Dauer von nur vier Femtosekunden (1 fs = 10 hoch minus15 Sekunden). „Als Folge der Wechselwirkung mit der Welle eines Lichtpulses zerfällt das Molekül – nach seiner Doppelionisation – in ein positiv geladenes C2H+ Ion und ein Proton, welche wir beide in dem Reaktionsmikroskop detektieren“, beschreibt Prof. Ali Alnaser. Für jeden Laserpuls, der mit den Molekülen in Wechselwirkung tritt, wurde die Wellenform exakt vermessen. Da Acetylen ein symmetrisches Molekül ist, brechen die C-H Bindungen auf beiden Seiten typischerweise mit der gleichen Wahrscheinlichkeit. In ihrem Experiment konnten die Forscher allerdings nachweisen, dass sich die Wahrscheinlichkeit, die linke bzw. die rechte C-H Bindung zu brechen, mit der Wellenform des Laserpulses steuern lässt (siehe Abbildung). Quantendynamische Simulationen zeigen, auf welche Art der Laser-Molekül-Wechselwirkung dieser Effekt zurückgeht. „Das bereits bekannte Schema, in dem molekulare Reaktionen mittels Elektronendynamik gesteuert werden, welche wiederum mit Hilfe der Wellenform kurzer Laserpulse erzeugt wird, funktioniert hier nicht“, erklärt Prof. de Vivie-Riedle. „Wir haben hier einen neuen Quantenkontrollpfad entdeckt, über den die Reaktion verläuft.“ Danach regt der aus wenigen Zyklen bestehende Laserpuls zunächst diejenigen Schwingungen an, die laser-aktiv sind. Eine dieser Schwingungen ist die anti-symmetrische Streckschwingung, bei der sich eine C-H Bindung verlängert, während sich die andere verkürzt. Wenn der Laserpuls sein maximales elektrisches Feld erreicht, entfernt er ein Elektron aus der CC-Dreifachbindung; das Molekül wird ionisiert. Bei diesem Prozess werden zusätzlich die laserinaktiven Schwingungsmoden angeregt. Eine dieser Moden ist die symmetrische CH-Streckschwingung, bei der sich beide H-Atome synchron auf die CC Gruppe zubewegen oder von ihr entfernen. Im weiteren Verlauf des Laserpulses wird das frei gesetzte Elektron auf das molekulare Kation zurückbeschleunigt, entfernt dort ein zweites Elektron, und es entsteht ein Acetylen Dikation, welches schnell in das C2H+ Ion und ein Proton dissoziiert, die in dem Experiment nachgewiesen werden. „Molekülschwingungen, die unabhängig voneinander angeregt werden, können die Messergebnisse nicht erklären. Voraussetzung für die von der Wellenform abhängige beobachtete Asymmetrie in der Verteilung der Reaktionsprodukte ist ein Quanteneffekt: die kohärente Überlagerung der symmetrischen und anti-symmetrischen Streckschwingung. Als Konsequenz dieser Interferenz kann es dazu kommen, dass nur eine C-H Bindung schwingt, während die andere unverändert bleibt“, erläutert Prof. de Vivie-Riedle. „Diese Art, das Molekül zu beeinflussen, führt zu dem beobachteten spezifischen C-H Bindungsbruch. Die Wellenform des Lasers kontrolliert die Überlagerung der Schwingungsmoden und damit die Richtung in die sich das Schwingungswellenpacket im Dikation bewegt“, ergänzt Prof. Matthias Kling. Die Forscher sehen die Ergebnisse ihrer Studien als „proof-of-principle“ für einen neuen Quantenkontrollmechanismus. „Die Kontrolle über die Laserwellenform ist allgemeiner Natur. Wir vermuten deshalb, dass die Methode auch für andere, komplexere molekulare Prozesse funktionieren könnte“, sagt Prof. Ali Alnaser, der seine Forschungen in diese Richtung ausweiten will. Er fügt hinzu: „In unserer Arbeit haben wir die Schwingungen nichtresonant angeregt. Eine bessere Kontrolle könnten wir erzielen, wenn wir eine resonante Anregung mit ultrakurzen Lichtpulsen im mittleren Infrarot vornehmen. Die dafür notwendigen Lasersysteme werden derzeit entwickelt. Sie ebnen den Weg, das Potential des neuen Kontrollschemas voll auszuschöpfen.“ [MK/OM] Originalveröffentlichung: A.S. Alnaser, M. Kübel, R. Siemering, B. Bergues, Nora G. Kling, K.J. Betsch, Y. Deng, J. Schmidt, Z.A. Alahmed, A.M. Azzeer, J. Ullrich, I. Ben-Itzhak, R. Moshammer, U. Kleineberg, F. Krausz, R. de Vivie-Riedle, and M.F. Kling Sub-femtosecond Steering of Hydrocarbon Deprotonation through Superposition of Vibrational Modes Nature Communications, DOI:10.1038/ncomms4800, 8. Mai 2014 Kontakt: Prof. Ali Alnaser Physics Department, American University of Sharjah PO Box 26666, Sharjah, United Arab Emirates Telefon: +97 / 165 152 340 http://www.innovations-report.de/html/berichte/biowissenschaften-chemie/lichtwellen-ermoeglichen-bevorzugten-bindungsbruch-in-symmetrischen-molekuelen.wi…

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Lichtwellen ermöglichen bevorzugten Bindungsbruch in symmetrischen Molekülen

E-Mail: aalnaser@aus.edu Prof. Dr. Regina de Vivie-Riedle Ludwig-Maximilians-Universität München Department Chemie Butenandt-Straße 11, 81377 München Telefon: +49 (0)89 / 2180 – 77 533 E-Mail: Regina.de_Vivie@cup.uni-muenchen.de Prof. Dr. Matthias Kling Labor für Attosekundenphysik Ludwig-Maximilians-Universität München, Max-Planck-Institut für Quantenoptik Hans-Kopfermann-Straße 1, Garching Telefon: +49 (0)89 / 32 905 -234 E-Mail: matthias.kling@mpq.mpg.de Dr. Olivia Meyer-Streng Max-Planck-Institut für Quantenoptik, Garching Presse- und Öffentlichkeitsarbeit Telefon: +49 (0)89 / 32 905 -213 E-Mail: olivia.meyer-streng@mpq.mpg.de Dr. Olivia Meyer-Streng | Max-Planck-Institut Weitere Informationen: http://www.mpq.mpg.de Weitere Berichte zu: > Acetylen > Bindung > Bindungsbruch > Elektron > LMU > Laserpuls > Ludwig-MaximiliansUniversität > Max-Planck-Institut > Molekül > Nature > Quantenoptik > Schwingungen > Wechselwirkung > Wellenform nächste Meldung

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Students feted under transparency initiative Shaikh Nahyan Bin Mubarak A1 Nahyan, Minister of Culture, Youth and Community Development, presented awards to the winners of the"Pearl Initiative case study for students of the state" contest, during a ceremony on Tuesday at the Park Rotana Hotel. The American University of Sharjah team took top honours with their study of measures to combat money laundering at Al fardan Exchange. Published on: Page:

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Gulf News

AUS launches eBook to help freshmen TO help freshmen adjust to their first year, American University of Sharjah (AUS), among the world's top 440 universities, has developed and launched a new eBook recently on â&#x20AC;&#x153;How to Survive Your First Year at an American University in the MENA Regionâ&#x20AC;?. As part of a thought leadership series of eBooks aimed at engaging the community through various outreach initiatives, the eBook identifies elements that will help students become acclimated to their new surroundings and have a successful first year, thereby setting a solid foundation for the rest of their time at university. Published on: 22/05/2014 Name: The Saudi Gazette (Jeddah Eddition) Page: 14

Kids find Arabic linguistically challenging The failure to recognise the challenges posed by the linguistic specificity of Arabic during early acquisition may account for Arab children's poor reading skills, argues American University of Sharjah linguistics Professor Dr Fatima Badry in her latest scholarly writing. Entitled, "Learning to read Arabic: Psycholinguistic and linguistic considerations," the article was presented at Kuwait University during the 2014 First Kuwait International Conference on Life Sciences. Published on: Page:

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The Gulf Today

DEWA hosts risk management conference H.H. DR. Sheikh Sultan bin Mohammed Al Qasimi, Supreme Council Member and Ruler of Sharjah and President of American University of Sharjah (AUS) Sunday met with a delegation of UN High Commissioner for Refugees and the delegations participating in the 74th session, specialised in International Refugee Law, which is being held under the generous patronage of H.H. for the first time in the Emirate of Sharjah. The Enterprise Risk Management Department in Dubai Electricity and Water Authority (DEWA), in partnership with the UK Institute of Risk Management, hosted the Developments in Enterprise Risk Management conference 2014, in Dubai, in the presence of Saeed Mohammed Al Tayer, and Saeed Mohammed Al Sharid, Member of the Board of Directors of DEWA, Mr. Abdulqader Obaid, Chairman, of the Internal Audit Association (UAE IAA), Executive Vice Presidents and Vice-Presidents at DEWA, and Richard Anderson, Chairman of the Institute of Risk Management, and a large number of experts and specialists working in the field of risk management from the public and private sectors. Part of DEWA's risk management challenge for the department responsible for tracking and identifying methods to mitigate risks, the Enterprise Risk Management conference is highlighting the best practices in the field by implementing suitable mechanisms. Published on: Page:

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The Gulf Time

Student mums find the right balance They say being a mother is the toughest job in the world. Lana Sawaf, 23, who is mother to eight-month-old Seema, is studying business administration at the American University of Dubai to give her child and herself a better future. Published on: Page:

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Radiating a human face They must be seen â&#x20AC;&#x201D; these ideas, executed in a fascinating realm, concern humans and their lives directly. Expressed in different forms, the observations on life from these emerging artists go as deep as to touch upon the most excruciating experience of humans getting blurred in the face of rapid material development. These artists have captured the moments that the world might have overlooked during the stroll towards more mundane advancements. Their artwork is a reminder about what may have been left or what may be missing in peopleâ&#x20AC;&#x2122;s present day life. Katara Art Centre (KAC) with its Community Supported Art (CSA) exhibition has brought to fore 20 artworks from both emerging and established artists for people in Doha to see. It has enough substance for people to have a look back and critically appreciate the past while taking a quick look into the future at the same time. The owl is wisdom, for instance, representative of a wise person. Vulture means the person is talkative and gossips a lot. Bear is an animal representing a big person who is polite at the same time, she added. Graduating as Graphic Designer from VCU-Qatar, Najla invites the viewer to read the piece, question it and define him/herself among these human-animal hybrid. Published on: Page:

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Name:

Gulf Times

AUS tops case study competition Sheikh Nahayan Bin Mabarak Al Nahayan, the UAE Minister of Youth, Culture and Community Development, congratulated the winners of the Pearl Initiative UAE Student Case Study Competition at a ceremony in Abu Dhabi on May 20. This is a goal that is directly in line with the Pearl initiativeâ&#x20AC;&#x2122;s mission to grow a knowledge base on regional and responsible best corporate practices. First place went to a team from the American University of Sharjah which profiled Al Fardan Exchangeâ&#x20AC;&#x2122;s anti-money laundering policies. Some of the studies were presented about Al Habtoor Group and Beeah as well as others . Published on: Page:

22/05/2014 4

Name:

Al Khaleej

American University of Sharjah issues 2nd electronic orientation book for new students American University of Sharjah announced issuing the second electronic book to help first-year students with their orientation.The university is one of the best 440 universities across the world. Published on: Section:

26/05/2014 General

Name:

Saudi Shopper

19/05/2014 General

Name:

Al Watan (Al Riyadh Edition)

Sharjah Environment Authority honors institutes collaborating in 7th wilderness campaign Hana Saif Al Suwaidi, Chairperson of the Environment and Natural Reserves Authority in Sharjah , has honored the cooperating , sponsoring institutes and the figures contributing in executing the activities of the seventh environmental awareness campaign desiganted to the people going to wilderness areas , at a ceremony held at Sharjah Chamber of Commerce and Industry . Among those honored University of Sharjah , Sharjah Roads and Transport Authority , Emirates Foundation for Youth Development and Takatof Voluntary Program as well as officials from American University of Sharjah and Beeah and many others . Published on: Section:

29/05/2014 local

Name:

Al Bayan

29/05/2014 Local

Name:

Al Fajr

Holy Quran and Sunnah Foundation sponsors AUS competition The Holy Quran and Sunnah Foundation in Sharjah sponsored the competition organized by the Islamic Club at the American University of Sharjah (AUS). Published on: 17/05/2014 Name: Al Fajr Page: 4

UGSRC winners announcedThe winners at the "United Arab Emirates Undergraduate Student Research Competition (UGSRC)" were announced, among which some from Abu Dhabi University (ADU), the American University of Sharjah (AUS), AUST, NYU Abu Dhabi Published on: Page:

26/05/2014 22

Name:

Al Fajr

Sports activities Al Jazeera University wrapped up the activities of the Higher Education Sports Union . The University of Sharjah, the American University of Sharjah, Zayed University, the UAEU, Abu Dhabi University, Khalifa University took part in the events Published on: Page:

27/05/2014 14

Name:

Al Ittihad

27/05/2014 Sports

Name:

Al Ittihad