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Abstract— Slow destruction of the far-red-absorbing form of phytochrome (Pfr ), which has been observed in light-grown oat and maize, occurs in light- and dark-grown Amaranthus, Pharbitis , and Brassica seedlings as well. Destruction of Pfr in these seedlings shows two phases: if a high level of Pfr is produced in dark-grown seedlings, the destruction is fast in the beginning and then slows after a low Pfr level has been reached. Slow Pfr destruction is predominant in light-grown tissue. 相似文献
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Luminescent [(NH(3))(4)Pt][Au(CN)(2)](2).1.5(H(2)O), which forms from aqueous solutions of [(NH(3))(4)Pt]Cl(2) and K[Au(CN)(2)], crystallizes with extended chains of the two ions with multiple close Pt...Au (3.2804(4) and 3.2794(4) A) and Au...Au (3.2902(5), 3.3312(5), and 3.1902(4) A) contacts. Nonluminescent [(NH(3))(4)Pt][Ag(CN)(2)](2).1.4(H(2)O) is isostructural with [(NH(3))(4)Pt][Au(CN)(2)](2).1.5(H(2)O). Treatment of [(NH(3))(6)Ni]Cl(2) with K[Au(CN)(2)] forms [(NH(3))(2)Ni][Au(CN)(2)](2) in which the [Au(CN)(2)](-) ions function as nitrile ligands toward nickel, which assumes a six-coordinate structure with trans NH(3) ligands. The [Au(CN)(2)](-) ions self-associate into linear columns with close Au...Au contacts of 3.0830(5) A, and pairs of gold ions in these chains make additional but longer (3.4246(5) A) contacts with other gold ions. 相似文献
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The reduction of Ar*GeCl (Ar* = C6H3-2,6-Trip2; Trip = C6H2-2,4,6-i-Pr3) with one equivalent of potassium leads to the formation of a germanium analogue of an alkyne Ar*GeGeAr* 1; reaction of 1 with 2,3-dimethyl-1,3-butadiene yields [Ar*Ge(CH2C(Me)C(Me)CH2)CH2C(Me)=]2 2, which was structurally characterized. 相似文献
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Torben Stender 《Linear algebra and its applications》2007,426(1):53-70
Rotation numbers and chain rotation numbers may be interpreted as a generalization of the imaginary parts for matrices. In dimension two they measure how the solutions of a linear autonomous differential equation rotate in the phase space, and they reduce to the imaginary parts of the eigenvalues of the system’s matrix. In higher dimensions they measure how a two-frame of vectors rotate under the induced flow in the plane which is spanned by the frame. For their calculation, only special sets in the oriented Grassmann manifold of planes are relevant, and to each of these sets corresponds a compact interval of chain rotation numbers. In this paper we will determine these relevant sets and calculate the corresponding sets of chain rotation numbers. 相似文献
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L. Merten 《Zeitschrift für Physik B Condensed Matter》1964,2(1):53-65
Due to the piezoelectric effect, dislocations in piezoelectric crystals carry electrical fields and (or) charges, which can be quite large locally. The properties of a 〈001〉-screw dislocation in a cubic crystal are investigated in detail. In the present first part, two limiting cases are treated, using the following suppositions: 1. No free charge carriers are present; the occurring electric field and the proper potential field are studied; 2. The electric field is negligible small; the charge density of the free charge carriers is examined. Numerical values for ZnS and GaAs, which are of technical importance, are calculated and discussed. For the depths of the flat potential valleys around the 〈001〉-dislocations, we obtained the values:ΔE=0,082 eV (ZnS) andΔE=0,049 eV (GaAs). 相似文献
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Jie Liu Shubhadip Mallick Yusheng Xie Corentin Grassin Belén Lucas Beate Schölermann Axel Pahl Rebecca Scheel Carsten Strohmann Christoph Protzel Thorsten Berg Christian Merten Slava Ziegler Herbert Waldmann 《Angewandte Chemie (International ed. in English)》2023,62(21):e202301955
Oxindoles and iso-oxindoles are natural product-derived scaffolds that provide inspiration for the design and synthesis of novel biologically relevant compound classes. Notably, the spirocyclic connection of oxindoles with iso-oxindoles has not been explored by nature but promises to provide structurally related compounds endowed with novel bioactivity. Therefore, methods for their efficient synthesis and the conclusive discovery of their cellular targets are highly desirable. We describe a selective RhIII-catalyzed scaffold-divergent synthesis of spirooxindole–isooxindoles and spirooxindole–oxindoles from differently protected diazooxindoles and N-pivaloyloxy aryl amides which includes a functional group-controlled Lossen rearrangement as key step. Unbiased morphological profiling of a corresponding compound collection in the Cell Painting assay efficiently identified the mitotic kinesin Eg5 as the cellular target of the spirooxindoles, defining a unique Eg5 inhibitor chemotype. 相似文献