Klein, Helmut

[["dc.bibliographiccitation.firstpage","452"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","Advanced Engineering Materials"],["dc.bibliographiccitation.lastpage","458"],["dc.bibliographiccitation.volume","11"],["dc.contributor.author","Klein, Helmut"],["dc.date.accessioned","2018-11-07T08:28:51Z"],["dc.date.available","2018-11-07T08:28:51Z"],["dc.date.issued","2009"],["dc.description.abstract","Diffraction imaging with hard X-rays (high-energy synchrotron radiation) using the detector sweeping techniques allows measurement of the texture and microstructure of polycrystalline materials with high orientation- and location-resolution. These techniques provide continuous two-dimensional images of different sections and projections of the six-dimensional \"orientation-location\" space. For the high orientation resolution case, it is possible to measure the orientation and location coordinates of up to 105 individual grains simultaneously. From these parameters, the grain size and shape can also be obtained, yielding the complete orientation stereology of the polycrystalline aggregate, which is required for its complete characterization. For the high location resolution case, the intensity at any point of the diagrams; corresponds to a pole density as a function of the orientation-location space."],["dc.description.sponsorship","German Research Foundation DFG; HASYLAB at DESY"],["dc.identifier.doi","10.1002/adem.200800368"],["dc.identifier.isi","000267853400005"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/16517"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.relation.issn","1527-2648"],["dc.relation.issn","1438-1656"],["dc.title","Principles of Highly Resolved Determination of Texture and Microstructure using High-Energy Synchrotron Radiation"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1381"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Journal of the American Ceramic Society"],["dc.bibliographiccitation.lastpage","1392"],["dc.bibliographiccitation.volume","101"],["dc.contributor.author","Neher, Sigmund H."],["dc.contributor.author","Klein, Helmut"],["dc.contributor.author","Kuhs, Werner F."],["dc.date.accessioned","2020-12-10T18:28:54Z"],["dc.date.available","2020-12-10T18:28:54Z"],["dc.date.issued","2017"],["dc.identifier.doi","10.1111/jace.2018.101.issue-3"],["dc.identifier.issn","0002-7820"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/76448"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.title","Determination of crystal size distributions in alumina ceramics by a novel X-ray diffraction procedure"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1"],["dc.bibliographiccitation.issue","1-4"],["dc.bibliographiccitation.journal","Marine Geology"],["dc.bibliographiccitation.lastpage","14"],["dc.bibliographiccitation.volume","244"],["dc.contributor.author","Bohrmann, Gerhard"],["dc.contributor.author","Kuhs, Werner F."],["dc.contributor.author","Klapp, Stephan A."],["dc.contributor.author","Techmer, Kirsten S."],["dc.contributor.author","Klein, Helmut"],["dc.contributor.author","Murshed, M. Mangir"],["dc.contributor.author","Abegg, Fritz"],["dc.date.accessioned","2018-11-07T10:57:49Z"],["dc.date.available","2018-11-07T10:57:49Z"],["dc.date.issued","2007"],["dc.description.abstract","The state of preservation of natural gas hydrate samples, recovered from 6 sites drilled during ODP Leg 204 at southern summit of Hydrate Ridge, Oregon Margin, has been investigated by X-ray diffraction (XRD) and cryo-scanning-electron-inicroscopy (cryo-SEM) techniques. A detailed characterization of the state of decomposition of gas hydrates is necessary since no pressurized autoclave tools were used for sampling and partial dissociation must have occurred during recovery prior to the quench and storage in liquid nitrogen. Samples from 16 distinct horizons have been investigated by synchrotron X-ray diffraction measurements at HASYLAB/ Hamburg. A full profile fitting analysis (\"Rietveld method\") of synchrotron XRD data provides quantitative phase determinations of the major sample constituents such as gas hydrate structure I (sI), hexagonal ice (Ih) and quartz. The ice content (Ih) in each sample is related to frozen water composed of both original existing pore water and the water from decomposed hydrates. Hydrate contents as measured by diffraction vary between 0 and 68 wt.% in the samples we measured. Samples with low hydrate content usually show micro-structural features in cryo-SEM ascribed to extensive decomposition. Comparing the appearance of hydrates at different scales, the grade of preservation seems to be primarily correlated with the contiguous volume of the original existing hydrate; the dissociation front appears to be indicated by micrometer-sized pores in a dense ice matrix. (c) 2007 Elsevier B.V. All rights reserved."],["dc.identifier.doi","10.1016/j.margeo.2007.05.003"],["dc.identifier.isi","000250150800001"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/50340"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Elsevier Science Bv"],["dc.relation.issn","0025-3227"],["dc.title","Appearance and preservation of natural gas hydrate from Hydrate Ridge sampled during ODP Leg 204 drilling"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1437"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","Journal of Applied Crystallography"],["dc.bibliographiccitation.lastpage","1439"],["dc.bibliographiccitation.volume","52"],["dc.contributor.author","Neher, Sigmund H."],["dc.contributor.author","Klein, Helmut"],["dc.contributor.author","Kuhs, Werner F."],["dc.date.accessioned","2020-12-10T18:25:57Z"],["dc.date.available","2020-12-10T18:25:57Z"],["dc.date.issued","2019"],["dc.identifier.doi","10.1107/S1600576719012159"],["dc.identifier.eissn","1600-5767"],["dc.identifier.pmid","31798363"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/17179"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/75893"],["dc.notes.intern","DOI Import GROB-354"],["dc.notes.intern","Merged from goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","FXD-CSD-GUI : a graphical user interface for the X-ray-diffraction-based determination of crystallite size distributions"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","550"],["dc.bibliographiccitation.journal","Journal of Synchrotron Radiation"],["dc.bibliographiccitation.lastpage","556"],["dc.bibliographiccitation.volume","18"],["dc.contributor.author","Raue, Lars"],["dc.contributor.author","Klein, Helmut"],["dc.date.accessioned","2018-11-07T08:54:50Z"],["dc.date.available","2018-11-07T08:54:50Z"],["dc.date.issued","2011"],["dc.description.abstract","Obtaining information about the intrinsic structure of polycrystalline materials is of prime importance owing to the anisotropic behaviour of individual crystallites. Grain orientation and its statistical distribution, i.e. the texture, have an important influence on the material properties. Crystallographic orientations play an important role in all kinds of polycrystalline materials such as metallic, geological and biological. Using synchrotron diffraction techniques the texture can be measured with high local and angular resolving power. Here methods are presented which allow the spatial orientation of the crystallites to be determined and information about the anisotropy of mechanical properties, such as elastic modulus or thermal expansion, to obtained. The methods are adapted to all crystal and several sample symmetries as well as to different phases, for example with overlapping diffraction peaks. To demonstrate the abilities of the methods, human dental enamel has been chosen, showing even overlapping diffraction peaks. Likewise it is of special interest to learn more about the orientation and anisotropic properties of dental enamel, since only basic information is available up to now. The texture of enamel has been found to be a tilted fibre texture of high strength (up to 12.5x). The calculated elastic modulus is up to 155 GPa and the thermal expansion up to 22.3 x 10(-6) degrees C(-1)."],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft (DFG); HASYLAB/DESY"],["dc.identifier.doi","10.1107/S0909049511011071"],["dc.identifier.isi","000292105500003"],["dc.identifier.pmid","21685670"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/22763"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-blackwell"],["dc.relation.issn","0909-0495"],["dc.title","Calculation of anisotropic properties of dental enamel from synchrotron data"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1264"],["dc.bibliographiccitation.issue","8"],["dc.bibliographiccitation.journal","Journal of Biomaterials Applications"],["dc.bibliographiccitation.lastpage","1273"],["dc.bibliographiccitation.volume","28"],["dc.contributor.author","Weizbauer, Andreas"],["dc.contributor.author","Modrejewski, Christian"],["dc.contributor.author","Behrens, Sabine"],["dc.contributor.author","Klein, Helmut"],["dc.contributor.author","Helmecke, Patrick"],["dc.contributor.author","Seitz, Jan-Marten"],["dc.contributor.author","Windhagen, Henning"],["dc.contributor.author","Moehwald, Kai"],["dc.contributor.author","Reifenrath, Janin"],["dc.contributor.author","Waizy, Hazibullah"],["dc.date.accessioned","2018-11-07T09:42:07Z"],["dc.date.available","2018-11-07T09:42:07Z"],["dc.date.issued","2014"],["dc.description.abstract","In this invitro study, magnesium plates of ZEK100 and MgCa0.8 alloy similar to common titanium alloy osteosynthesis plates were investigated as degradable biomedical materials with a focus on primary stability. Immersion tests were performed in Hank's Balanced Salt Solution at 37celcius. The bending strength of the samples was determined using the four-point bending test according to ISO 9585:1990. The initial strength of the noncorroded ZEK100 plate was 11% greater than that of the MgCa0.8 plate; both were approximately 65% weaker than a titanium plate. The bending strength was determined after 48 and 96 h of immersion in Hank's Balanced Salt Solution; both magnesium alloys decreased by approximately 7% after immersion for 96 h. The degradation rate and the Mg2+ release of ZEK100 were lower than those of MgCa0.8. Strong pitting and filiform corrosion were observed in the MgCa0.8 samples after 96 h of immersion. The surface of the ZEK100 plates exhibited only small areas of filiform corrosion. The results of this invitro study indicate that the ZEK100 alloy may be more suitable for biomedical applications."],["dc.description.sponsorship","German Research Society (DFG) [SFB 599]"],["dc.identifier.doi","10.1177/0885328213506758"],["dc.identifier.isi","000333399200012"],["dc.identifier.pmid","24105427"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/33885"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Sage Publications Ltd"],["dc.relation.issn","1530-8022"],["dc.relation.issn","0885-3282"],["dc.relation.orgunit","Fakultät für Geowissenschaften und Geographie"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Comparative invitro study and biomechanical testing of two different magnesium alloys"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","222"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Advanced Engineering Materials"],["dc.bibliographiccitation.lastpage","227"],["dc.bibliographiccitation.volume","12"],["dc.contributor.author","Tommaseo, Caterina Elisabetta"],["dc.contributor.author","Klein, Helmut"],["dc.date.accessioned","2018-11-07T08:45:07Z"],["dc.date.available","2018-11-07T08:45:07Z"],["dc.date.issued","2010"],["dc.description.abstract","The development of the recrystallization and annealing textures of Al-Mn alloys with 0.4, 0.7 and 1 wt.-% manganese is analyzed using specific techniques that allow the detection of changes in grain orientation during in situ annealing. In order to investigate the evolution of texture components during annealing, highly rolled samples were annealed from room temperature to 500 C at a constant heating rate. The advantage of in situ annealing experiments using synchrotron radiation is the detection of grain orientations over time, which allows observation of the development of the recrystallization and annealing textures in a sample. In fact, the recrystallization and annealing textures in the Al-0.4Mn are characterized by an interruption in the detection of most of the grain orientations between 380 and 425 C and by competition between the cube {001}< 100 >, {011}< 1-33 >, {011}< 0-11 > and rotated-cube {001}< 110 > grain orientations, where the latter is detected until the end of the experiment. In the Al-0.7Mn sample a competition between the cube {001}< 100 >, {011}< 100 >, and rotated cube {001}< 110 >, {011}< 0-11 > grain orientations is observed. In the sample with the highest manganese concentration (1 wt.-%) an unhindered grain growth of all possible grain orientations with a high amount of the {011}< 0-11 > grain orientation is observed. The evolution of the resulting local textures is discussed in terms of preferentially oriented grain growth depending on the temperature and manganese concentration."],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft [KL1402/2-1]"],["dc.identifier.doi","10.1002/adem.200900267"],["dc.identifier.isi","000277297300019"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/20358"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-blackwell"],["dc.relation.issn","1438-1656"],["dc.title","Oriented Grain Growth Analyses With In Situ Annealing Experiments Using High Energy Synchrotron Radiation"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","856"],["dc.bibliographiccitation.issue","8"],["dc.bibliographiccitation.journal","Catalysts"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Ronge, Emanuel"],["dc.contributor.author","Hildebrandt, Sonja"],["dc.contributor.author","Grutza, Marie-Luise"],["dc.contributor.author","Klein, Helmut"],["dc.contributor.author","Kurz, Philipp"],["dc.contributor.author","Jooss, Christian"],["dc.date.accessioned","2021-04-14T08:23:47Z"],["dc.date.available","2021-04-14T08:23:47Z"],["dc.date.issued","2020"],["dc.description.sponsorship","Open-Access-Publikationsfonds 2020"],["dc.identifier.doi","10.3390/catal10080856"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/17511"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/81047"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-399"],["dc.notes.intern","Merged from goescholar"],["dc.notes.intern","Merged from goescholar"],["dc.relation.eissn","2073-4344"],["dc.relation.orgunit","Fakultät für Physik"],["dc.relation.orgunit","Institut für Materialphysik"],["dc.rights","CC BY 4.0"],["dc.rights.uri","http://creativecommons.org/licenses/by/4.0/"],["dc.title","Structure of Nanocrystalline, Partially Disordered MoS2+δ Derived from HRTEM—An Abundant Material for Efficient HER Catalysis"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","18"],["dc.bibliographiccitation.journal","Circulation"],["dc.bibliographiccitation.volume","118"],["dc.contributor.author","De Ferrari, Gaetano M."],["dc.contributor.author","Sanzo, Antonio"],["dc.contributor.author","Borggrefe, Martin M."],["dc.contributor.author","Wolpert, Christian"],["dc.contributor.author","Kuschyk, Jürgen"],["dc.contributor.author","Schoene, Antonina"],["dc.contributor.author","Crijns, Harry J. G. M."],["dc.contributor.author","Dennert, Robert"],["dc.contributor.author","Milasinovic, Goran"],["dc.contributor.author","Raspopovic, Srdjan"],["dc.contributor.author","Klein, Helmut"],["dc.contributor.author","Smid, Jan"],["dc.contributor.author","Gavazzi, Antonello"],["dc.contributor.author","Iacovoni, Attilio"],["dc.contributor.author","Zabel, Markus"],["dc.contributor.author","Schwartz, Peter J."],["dc.date.accessioned","2018-11-07T11:09:52Z"],["dc.date.available","2018-11-07T11:09:52Z"],["dc.date.issued","2008"],["dc.identifier.isi","000262104502355"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/53095"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Lippincott Williams & Wilkins"],["dc.publisher.place","Philadelphia"],["dc.relation.conference","81st Annual Scientific Session of the American-Heart-Association"],["dc.relation.eventlocation","New Orleans, LA"],["dc.title","Chronic Vaguer Nerve Stimulation in Patients with Chronic Heart Failure is Feasible and Appears Beneficial"],["dc.type","conference_abstract"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","116"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Marine and Petroleum Geology"],["dc.bibliographiccitation.lastpage","125"],["dc.bibliographiccitation.volume","27"],["dc.contributor.author","Klapp, Stephan A."],["dc.contributor.author","Bohrmann, Gerhard"],["dc.contributor.author","Kuhs, Werner F."],["dc.contributor.author","Murshed, M. Mangir"],["dc.contributor.author","Pape, Thomas"],["dc.contributor.author","Klein, Helmut"],["dc.contributor.author","Techmer, Kirsten S."],["dc.contributor.author","Heeschen, Katja U."],["dc.contributor.author","Abegg, Friedrich"],["dc.date.accessioned","2018-11-07T08:48:06Z"],["dc.date.available","2018-11-07T08:48:06Z"],["dc.date.issued","2010"],["dc.description.abstract","Gas hydrate samples from various locations in the Gulf of Mexico (GOM) differ considerably in their microstructure. Distinct microstructure characteristics coincide with discrete crystallographic structures, gas compositions and calculated thermodynamic stabilities. The crystallographic structures were established by X-ray diffraction, using both conventional X-ray sources and high-energy synchrotron radiation. The microstructures were examined by cryo-stage Field-Emission Scanning Electron Microscopy (FE-SEM). Good sample preservation was warranted by the low ice fractions shown from quantitative phase analyses. Gas hydrate structure II samples from the Green Canyon in the northern GOM had methane concentrations of 70-80% and up to 30% of C-2-C-5 of measured hydrocarbons. Hydrocarbons in the crystallographic structure I hydrate from the Chapopote asphalt volcano in the southern GOM was comprised of more than 98% methane. Fairly different microstructures were identified for those different hydrates: Pores measuring 200-400 nm in diameter were present in structure I gas hydrate samples; no such pores but dense crystal surfaces instead were discovered in structure II gas hydrate. The stability of the hydrate samples is discussed regarding gas composition, crystallographic structure and microstructure. Electron microscopic observations showed evidence of gas hydrate and liquid oil co-occurrence on a micrometer scale. That demonstrates that oil has direct contact to gas hydrates when it diffuses through a hydrate matrix. (C) 2009 Elsevier Ltd. All rights reserved."],["dc.identifier.doi","10.1016/j.marpetgeo.2009.03.004"],["dc.identifier.isi","000272308200010"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/21128"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Elsevier Sci Ltd"],["dc.relation.issn","0264-8172"],["dc.title","Microstructures of structure I and II gas hydrates from the Gulf of Mexico"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]