Search Results - (Author, Cooperation:Hilgenfeldt)
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1FIS Bildung LiteraturdatenbankStaff View
Type of Medium: articlePublication Date: 1999Keywords: Sachinformation ; Naturwissenschaften ; Akustik ; Licht ; Optik ; Physik ; Schall ; SonolumineszenzIn: Spektrum der Wissenschaft, (1999) H. 11, S. 22-24, 26, 0170-2971Language: German -
2FIS Bildung LiteraturdatenbankStaff View
Type of Medium: articlePublication Date: 1994Keywords: Experiment ; Sachinformation ; Naturwissenschaften ; Mechanik ; Physik ; Chaos ; Entstehung ; Ordnung ; SystemIn: Spektrum der Wissenschaft, (1994) H. 1, S. 72-81, 0170-2971Language: GermanNote: Literaturangaben -
3Latest Papers from Table of Contents or Articles in PressStaff View
Publication Date: 2018-06-12Publisher: American Physical Society (APS)Print ISSN: 0031-9007Electronic ISSN: 1079-7114Topics: PhysicsKeywords: Polymer, Soft Matter, Biological, Climate, and Interdisciplinary PhysicsPublished by: -
4Articles: DFG German National LicensesStaff View
ISSN: 1089-7666Source: AIP Digital ArchiveTopics: PhysicsNotes: Single bubble sonoluminescence is not an exotic phenomenon but can quantitatively be accounted for by applying a few well-known, simple concepts: the Rayleigh–Plesset dynamics of the bubble's radius, polytropic uniform heating of the gas inside the bubble during collapse, the dissociation of molecular gases, and thermal radiation of the remaining hot noble gas, where its finite opacity (transparency for its own radiation) is essential. A system of equations based on these ingredients correctly describes the widths, shapes, intensities, and spectra of the emitted light pulses, all as a function of the experimentally adjustable parameters, namely, driving pressure, driving frequency, water temperature, and the concentration and type of the dissolved gas. The theory predicts that the pulse width of strongly forced xenon bubbles should show a wavelength dependence, in contrast to argon bubbles. © 1999 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
5Articles: DFG German National LicensesHermann, Klaus ; Phillips, M. Ian ; Hilgenfeldt, Ulrich ; Raizada, Mohan K.
Oxford, UK : Blackwell Publishing Ltd
Published 1988Staff ViewISSN: 1471-4159Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicineNotes: Abstract: This study focuses on the ability of primary rat brain cells in culture to synthesize angiotensinogen, angio-tensin I, and angiotensin II. HPLC in combination with radioimmunoassay was used to characterize these compounds. Following incubation with 3H-labeled isoleucine, radioactively labeled angiotensinogen with an approximate molecular weight of 25,000 was identified in both glial and neuronal cells. Other molecular weight forms of angiotensinogen with molecular weights of about 300 and 160,000 were present in both cell types. In addition to angiotensinogen, radioactively labeled angiotensin I and angiotensin II were also synthesized by neuronal and glial cells. These results suggest that glial and neuronal cells can synthesize angiotensinogen, angiotensin I, and angiotensin II in a similar manner shown for the peripheral renin angiotensin system.Type of Medium: Electronic ResourceURL: -
6Articles: DFG German National LicensesHilgenfeldt, Sascha ; Lohse, Detlef ; Brenner, Michael P.
[S.l.] : American Institute of Physics (AIP)
Published 1996Staff ViewISSN: 1089-7666Source: AIP Digital ArchiveTopics: PhysicsNotes: Sound driven gas bubbles in water can emit light pulses. This phenomenon is called sonoluminescence (SL). Two different phases of single bubble SL have been proposed: diffusively stable and diffusively unstable SL. We present phase diagrams in the gas concentration versus forcing pressure state space and also in the ambient radius versus gas concentration and versus forcing pressure state spaces. These phase diagrams are based on the thresholds for energy focusing in the bubble and two kinds of instabilities, namely (i) shape instabilities and (ii) diffusive instabilities. Stable SL only occurs in a tiny parameter window of large forcing pressure amplitude Pa∼1.2–1.5 atm and low gas concentration of less than 0.4% of the saturation. The upper concentration threshold becomes smaller with increased forcing. Our results quantitatively agree with experimental results of Putterman's UCLA group on argon, but not on air. However, air bubbles and other gas mixtures can also successfully be treated in this approach if in addition (iii) chemical instabilities are considered. All statements are based on the Rayleigh–Plesset ODE approximation of the bubble dynamics, extended in an adiabatic approximation to include mass diffusion effects. This approximation is the only way to explore considerable portions of parameter space, as solving the full PDEs is numerically too expensive. Therefore, we checked the adiabatic approximation by comparison with the full numerical solution of the advection diffusion PDE and find good agreement. © 1996 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
7Articles: DFG German National LicensesStaff View
ISSN: 1089-7666Source: AIP Digital ArchiveTopics: PhysicsType of Medium: Electronic ResourceURL: -
8Articles: DFG German National LicensesLohse, Detlef ; Hilgenfeldt, Sascha
College Park, Md. : American Institute of Physics (AIP)
Published 1997Staff ViewISSN: 1089-7690Source: AIP Digital ArchiveTopics: PhysicsChemistry and PharmacologyNotes: In this paper we elaborate on the idea [Lohse et al., Phys. Rev. Lett. 78, 1359–1362 (1997)] that (single) sonoluminescing air bubbles rectify argon. The reason for the rectification is that nitrogen and oxygen dissociate and their reaction products dissolve in water. We give further experimental and theoretical evidence and extend the theory to other gas mixtures. We show that in the absence of chemical reactions (e.g., for inert gas mixtures) gas accumulation in strongly acoustically driven bubbles can also occur. © 1997 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
9Articles: DFG German National LicensesStaff View
ISSN: 1089-7666Source: AIP Digital ArchiveTopics: PhysicsType of Medium: Electronic ResourceURL: -
10Articles: DFG German National LicensesStaff View
ISSN: 1476-4687Source: Nature Archives 1869 - 2009Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsNotes: [Auszug] reply The comment by Putterman et al. in essence addresses two questions: the role of water vapour inside bubbles that undergo single-bubble sonoluminescence, and the use of Rayleigh–Plesset dynamics to describe collapsing bubbles. Regarding the first point, water ...Type of Medium: Electronic ResourceURL: -
11Articles: DFG German National LicensesStaff View
ISSN: 1476-4687Source: Nature Archives 1869 - 2009Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsNotes: [Auszug] The ability of collapsing (cavitating) bubbles to focus and concentrate energy, forces and stresses is at the root of phenomena such as cavitation damage, sonochemistry or sonoluminescence. In a biomedical context, ultrasound-driven microbubbles have been used to enhance contrast in ultrasonic ...Type of Medium: Electronic ResourceURL: -
12Articles: DFG German National LicensesHilgenfeldt, Sascha ; Grossmann, Siegfried ; Lohse, Detlef
[s.l.] : Macmillan Magazines Ltd.
Published 1999Staff ViewISSN: 1476-4687Source: Nature Archives 1869 - 2009Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsNotes: [Auszug] Ultrasonically driven gas bubbles in liquids can emit intense bursts of light when they collapse. The physical mechanism for single-bubble sonoluminescence has been much debated,. The conditions required for, and generated by, bubble collapse can be deduced within the framework of a ...Type of Medium: Electronic ResourceURL: -
13Articles: DFG German National LicensesStaff View
ISSN: 0005-2744Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyType of Medium: Electronic ResourceURL: -
14Articles: DFG German National LicensesStaff View
ISSN: 0005-2744Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyType of Medium: Electronic ResourceURL: -
15Articles: DFG German National LicensesStaff View
ISSN: 0005-2795Keywords: (Rat) ; Angiotensinogen ; Renin substrate ; Sialic acidSource: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyType of Medium: Electronic ResourceURL: -
16Articles: DFG German National LicensesStaff View
ISSN: 0014-5793Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyChemistry and PharmacologyPhysicsType of Medium: Electronic ResourceURL: -
17Articles: DFG German National LicensesStaff View
ISSN: 0014-5793Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyChemistry and PharmacologyPhysicsType of Medium: Electronic ResourceURL: -
18Articles: DFG German National LicensesStaff View
ISSN: 0014-5793Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyChemistry and PharmacologyPhysicsType of Medium: Electronic ResourceURL: -
19Articles: DFG German National LicensesKrattenmacher, R. ; Knauthe, R. ; Parczyk, K. ; Walker, A. ; Hilgenfeldt, U. ; Fritzemeier, K.H.
Amsterdam : ElsevierStaff ViewISSN: 0960-0760Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyChemistry and PharmacologyType of Medium: Electronic ResourceURL: -
20Articles: DFG German National LicensesStaff View
ISSN: 0960-0760Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyChemistry and PharmacologyType of Medium: Electronic ResourceURL: