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31.
Y. J. Cho C. R. Diminnie R. W. Freese E. Z. Andalafte 《Mathematische Nachrichten》1992,157(1):225-234
A triple (x, y, z) in a linear 2-normed space (X, ‖.,.‖) is called an isosceles orthogonal triple, denoted |(x, y, z), if |(.,.,.) is said to be homogeneous if |(x, y, z) implies |(ax, y, z) for all real a and it is additive if |(x1, y, z) and |(x2, y, z) imply that |(x1 + x2, y, z). In addition to developing some basic properties of |(.,.,.), this paper shows that under the assumption of strict convexity, every subspace of X of dimension ≤ 3 contains an isosceles orthogonal triple. Further, if (X, ‖.,.‖) is strictly convex and |(…,.) is either homogeneous or additive, then (X, ‖.,.‖) is a 2-inner product space. 相似文献
32.
Masaru Kawakami Katherine Byrne Bhavin S Khatri Tom C B McLeish D Alastair Smith 《Chemphyschem》2006,7(8):1710-1716
The viscoelastic properties of single poly(ethylene glycol) (PEG) molecules were measured by analysis of thermally and magnetically driven oscillations of an atomic force microscope (AFM) cantilever/molecule system. The molecular and monomer stiffness and friction of the PEG polymer were derived using a simple harmonic oscillator (SHO) model. Excellent agreement between the values of these two parameters obtained by the two approaches indicates the validity of the SHO model under the experimental regimes and the excellent reproducibility of the techniques. A sharp minimum in the monomeric friction is seen at around 180 pN applied force which we propose is due to a force induced change in the shape of the energy landscape describing the conformational transition of PEG from a helical to a planar state, which in turn affects the timescale of the transition and therefore modifies the measured internal friction. A knowledge of the viscoelastic response of PEG monomers is particularly important since PEG is widely used as a linker molecule for tethering groups of interest to the AFM tip in force spectroscopy experiments, and we show here that care must be exercised because of the force-dependent viscoelastic properties of these linkers. 相似文献
33.
C. Allen Chang Tamar E. Woodhouse Qihui Wu Ceshing Sheu Katherine McManus 《中国化学会会志》1988,35(4):253-260
Substitution-inert metal complexes, [Co(edda)(H2O)2]+, (Co(edda)(en)]+, [Co(edda)(dmen)]+, [Co(en)2-(gly)]2+, [Co(en)2(acac)]2+, and [Co(trien)(gly)]2+ in their nitrate salt solutions are used as eluents in nonsuppressed cation chromatography (where edda = ethylenediamine-N,N′-diacetic acid, en = ethylenediamine, dmen = N,N′-dime-thylethylenediamine, gly = glycine, acac = acetylacetone, and trien = triethylenetetraamine). It is found that all the mono- and di-valent charged complexes can be used to separate alkali and alkaline earth metal cations, respectively. The separations for monovalent cations are sometimes comparable to those using ultrapure HNO3 solutions. However, the divalent Ca2+ and Sr2+ ions cannot be resolved using the metal complex eluents. On the other hand, a selected, direct non-suppressed IC separation of zinc(II) and cadmium(II) ions is demonstrated for the first time using a substitution-inert metal complex eluent and a conductivity detector. Comparisons of these eluents with those reported previously, i. e. HNO3 and ethylenediammonium salt solution are made and explanations are proposed to account for the different selectivities observed where possible. The future development of this technique is also briefly discussed. 相似文献
34.
It is shown that if is any variety of algebras all of whose congruence lattices are modular, then the congruence lattice of every algebra in satisfies the Arguesian law. 相似文献
35.
36.
Chen Hui Sharma Sunil K. Sharma Priyanka R. Chi Kai Fung Eric Aubrecht Katherine Keroletswe Ngonye Chigome Samuel Hsiao Benjamin S. 《Cellulose (London, England)》2021,28(13):8611-8628
Cellulose - Mercury contamination in drinking water is a worldwide problem due to its severely harming effects on the human body. A nanostructured natural bioadsorbent, carboxycellulose nanofiber... 相似文献
37.
Katherine M. Byrd Chitra Subramanian Jacqueline Sanchez Hashim F. Motiwala Weiya Liu Prof. Mark S. Cohen Prof. Jeffrey Holzbeierlein Prof. Brian S. J. Blagg 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(20):6921-6931
Development of heat shock protein 90 (Hsp90) C‐terminal inhibitors has emerged as an exciting strategy for the treatment of cancer. Previous efforts have focused on modifications to the natural products novobiocin and coumermycin. Moreover, variations in both the sugar and amide moieties have been extensively studied, whereas replacements for the coumarin core have received less attention. Herein, 24 cores were synthesized with varying distances and angles between the sugar and amide moieties. Compounds that exhibited good anti‐proliferative activity against multiple cancer cell lines and Hsp90 inhibitory activity, were those that placed the sugar and amide moieties between 7.7 and 12.1 Å apart along with angles of 180°. 相似文献
38.
Dr. Lina M. Aguirre-Díaz Marcelo Echeverri Dr. Katherine Paredes-Gil Dr. Natalia Snejko Dr. Berta Gómez-Lor Prof. Dr. Enrique Gutiérrez-Puebla Prof. Dr. M. Ángeles Monge 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(16):5298-5306
Three new cadmium-based coordination polymers, denoted [Cd(hfipbb)(4,4’-bipy)] ( CdPF-1 ), [Cd(hfipbb)(2,2’-bipy)] ( CdPF-2 ), and [Cd(hfipbb)(1,10-phen)] ( CdPF-3 ), have been hydrothermally synthesized by using the well-known V-shaped organic linker 4,4’-(hexafluoroisopropylidene)bis(benzoic acid) (H2hfipbb), together with different nitrogenated auxiliary linkers. Considering the d10 configuration of the transition metal selected, the luminescent properties for these CdPF-n materials were explored, finding that materials CdPF-2 and CdPF-3 act as excellent sensors in the detection of explosive nitro aromatic compounds. The photoluminescence properties of CdPF-2 and CdPF-3 revealed that significant and sensitive fluorescence quenching was observed toward NP (nitrophenol) for CdPF-2 and PA (picric acid) for CdPF-3 in MeOH suspensions. 相似文献
39.
Katherine K. Wallman 《CHANCE》2013,26(1):36-44
Abstract Causality: Models, Reasoning, and Inference by Judea Pearl, Cambridge, U.K.: Cambridge University Press, 2000. Reviewed by Roderick P. McDonald 相似文献