H. Grimmer  W. Bollmann  D. H. Warrington 《Acta Crystallographica. Section A, Foundations and Advances》1974,30(2):197-207

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Hans Grimmer 《Acta Crystallographica. Section A, Foundations and Advances》2009,65(2):145-155

Litvin [Acta Cryst. (2008), A 64 , 419–424 and supplementary material] extends much of the information contained in Volume A of International Tables for Crystallography for the 230 space‐group types to the 1651 types of Shubnikov space groups, using Opechowski–Guccione (OG) notation for the space groups with a black–white lattice. It is pointed out that OG notation has crucial disadvantages compared to Belov–Neronova–Smirnova (BNS) notation. It is shown how Litvin's diagrams of symmetry elements for the orthorhombic Shubnikov space groups can be interpreted in terms of BNS symbols and how those containing e‐glides can be simplified. A number of mistakes in the diagrams of Litvin are corrected.  相似文献   

    

Hans Grimmer 《Acta Crystallographica. Section A, Foundations and Advances》2008,64(4):459-464

Quasicrystals (QC) with two‐dimensional quasiperiodic and one‐dimensional periodic structure are considered. Their symmetry can be described by embedding the three‐dimensional physical space V_E in a five‐dimensional superspace V, which is the direct sum of V_E and a two‐dimensional internal space V_I. A displacement v in V can be written as v = u + w , where u ∈V_E and w  ∈V_I. If the QC has a point group P in V_E that is crystallographic, it is assumed that w and a vector u ′∈V_E lying in the plane in which the crystal is quasiperiodic transform under equivalent representations of P, inequivalent ones if the point group is 5‐, 8‐, 10‐ or 12‐gonal. From the Neumann principle follow restrictions on the form of the phonon, phason and phonon–phason coupling contributions to the elastic stiffness matrix that can be determined by combining the restrictions obtained for a set of elements generating the point group of interest. For the phonon part, the restrictions obtained for the generating elements do not depend on the system to which the point group belongs. This remains true for the phason and coupling parts in the case of crystallographic point groups but, in general, breaks down for the non‐crystallographic ones. The form of the symmetric 12 × 12 matrix giving the phonon, phason and phonon–phason coupling contributions to the elastic stiffness is presented in graphic notation.  相似文献   

    

H. Grimmer 《Acta Crystallographica. Section A, Foundations and Advances》1989,45(1):FC1-FC2

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Profile of the polycyclic aromatic hydrocarbons from used engine oil — inventory by GCGC/MS — PAH in environmental materials,Part 2     

G. Grimmer  J. Jacob  K. W. Naujack  G. Dettbarn 《Analytical and bioanalytical chemistry》1981,309(1):13-19

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A comparison theorem for a class of nonlinear differential inequalities     

R. C. Grimmer  Paul Waltman 《Monatshefte für Mathematik》1968,72(2):133-136

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Modellversuche zur Phytotoxizität von Halogenhohlenwasserstoffen     

Gernot Grimmer  Werner Schmidt 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》1986,98(9):807-808

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G. Grimmer  J. Jacob  K. -W. Naujack 《Fresenius' Journal of Analytical Chemistry》1981,306(5):347-355

Summary Polycyclic aromatic hydrocarbons (= PAH), sulphur containing and oxygen containing polycyclic aromatic compounds (= S-resp. O-PAC) which occur in concentrations higher than 0.02 mg/kg in a lubricating oil sample were identified by comparison with reference substances (34) or, if reference compounds are lacking, characterized by mass spectrometry (58 compounds). Glass capillary gas chromatography combined with mass spectrometry was used for this inventory. Mass spectra of typical individuals from several classes (S-PAC, O-PAC, and methyl-derivatives) are discussed in detail.The profile of polycyclic aromatic compounds (= PAC) contained in mineral oils is significantly different from that obtained by incomplete combustion or pyrolysis of organic materials.To get a survey of the range of PAC-concentration in different engine oils, 22 commercial samples have been examined for a selected number of PAC.Inventory and Biological Impact of Polycyclic Carcinogens in the Environment, Part 7  相似文献   

Profile of the polycyclic aromatic hydrocarbons from lubricating oils inventory by GCGC/MS — PAH in environmental materials,part 1     

G. Grimmer  J. Jacob  K. -W. Naujack 《Analytical and bioanalytical chemistry》1981,306(5):347-355

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Philipp Kramer  Jennifer Grimmer  Michael Bolte  Georg Manolikakes 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(37):13190-13193

A novel method for the highly stereoselective synthesis of tetrahydropyrans is reported. This domino reaction is based on a twofold addition of enamides to aldehydes followed by a subsequent cyclization and furnishes fully substituted tetrahydropyrans in high yields. Three new σ‐bonds and five continuous stereogenic centers are formed in this one‐pot process with a remarkable degree of diastereoselectivity. In most cases, the formation of only one out of 16 possible diastereomers is observed. Two different stereoisomers can be accessed in a controlled fashion starting either from an E‐ or a Z‐configured enamide.  相似文献