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排序方式: 共有471条查询结果,搜索用时 15 毫秒
461.
We show that the famous maximum angle condition in the finite element analysis is not necessary to achieve the optimal convergence
rate when simplicial finite elements are used to solve elliptic problems. This condition is only sufficient. In fact, finite
element approximations may converge even though some dihedral angles of simplicial elements tend to π. 相似文献
462.
Crystallization studies of C-methyl pyrogallarene with potassium, rubidium and caesium bromides or chlorides resulted in a hydrogen bonded molecular cage in which the alkali metal cations are eta6 coordinated to aromatic rings via strong cation-pi interactions. 相似文献
463.
Rosenholm JM Penninkangas A Lindén M 《Chemical communications (Cambridge, England)》2006,(37):3909-3911
A simple method for surface functionalization of large-pore mesoporous silica by hyperbranching polymerization resulting in a high loading of amine groups is presented. 相似文献
464.
Antti Hannukainen Sergey Korotov Tomáš Vejchodský 《Journal of Computational and Applied Mathematics》2009
In this paper we analyse the discrete maximum principle (DMP) for a stationary diffusion-reaction problem solved by means of prismatic finite elements. We derive geometric conditions on the shape parameters of the prismatic partitions which guarantee validity of the DMP. The presented numerical tests show the sharpness of the obtained conditions. 相似文献
465.
J Hakala J Dobaczewski D Gorelov T Eronen A Jokinen A Kankainen VS Kolhinen M Kortelainen ID Moore H Penttilä S Rinta-Antila J Rissanen A Saastamoinen V Sonnenschein J Aystö 《Physical review letters》2012,109(3):032501
Atomic masses of the neutron-rich isotopes ^{121-128}Cd, ^{129,131}In, ^{130-135}Sn, ^{131-136}Sb, and ^{132-140}Te have been measured with high precision (10?ppb) using the Penning-trap mass spectrometer JYFLTRAP. Among these, the masses of four r-process nuclei ^{135}Sn, ^{136}Sb, and ^{139,140}Te were measured for the first time. An empirical neutron pairing gap expressed as the odd-even staggering of isotopic masses shows a strong quenching across N=82 for Sn, with a Z dependence that is unexplainable by the current theoretical models. 相似文献
466.
Lindgren A Gisselbrecht M Burmeister F Naves de Brito A Kivimäki A Sorensen SL 《The Journal of chemical physics》2005,122(11):114306
Electron-ion-ion coincidence measurements carried out at discrete resonances near the N 1s threshold in ammonia are reported. The measured coincidence spectra show clear alignment of the molecule upon resonant core-electron excitation. The coincidence data are analyzed to extract information about the molecule in the excited state by simulating the alignment and the dissociation processes. Dynamic changes in molecular geometry are found as the photon energy is scanned through the N 1s-->4a(1) resonance, whereas for the N 1s-->2e state the geometry and kinetic energy released upon dissociation remain unchanged. The alignment of the core-excited molecules is found to be preserved even in two-step dissociation processes. 相似文献
467.
Self‐Assembly of Amphiphilic Janus Dendrimers into Mechanically Robust Supramolecular Hydrogels for Sustained Drug Release 下载免费PDF全文
Dr. Sami Nummelin Ville Liljeström Dr. Eve Saarikoski Dr. Jarmo Ropponen Dr. Antti Nykänen Dr. Veikko Linko Prof. Jukka Seppälä Prof. Jouni Hirvonen Prof. Olli Ikkala Dr. Luis M. Bimbo Prof. Mauri A. Kostiainen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(41):14433-14439
Compounds that can gelate aqueous solutions offer an intriguing toolbox to create functional hydrogel materials for biomedical applications. Amphiphilic Janus dendrimers with low molecular weights can readily form self‐assembled fibers at very low mass proportion (0.2 wt %) to create supramolecular hydrogels (G′?G′′) with outstanding mechanical properties and storage modulus of G′>1000 Pa. The G′ value and gel melting temperature can be tuned by modulating the position or number of hydrophobic alkyl chains in the dendrimer structure; thus enabling exquisite control over the mesoscale material properties in these molecular assemblies. The gels are formed within seconds by simple injection of ethanol‐solvated dendrimers into an aqueous solution. Cryogenic TEM, small‐angle X‐ray scattering, and SEM were used to confirm the fibrous structure morphology of the gels. Furthermore, the gels can be efficiently loaded with different bioactive cargo, such as active enzymes, peptides, or small‐molecule drugs, to be used for sustained release in drug delivery. 相似文献
468.
Muckenhoupt Ap-properties of Distance Functions and Applications to Hardy–Sobolev -type Inequalities
Dyda Bartłomiej Ihnatsyeva Lizaveta Lehrbäck Juha Tuominen Heli Vähäkangas Antti V. 《Potential Analysis》2019,50(1):83-105
Potential Analysis - Let X be a metric space equipped with a doubling measure. We consider weights w(x) = dist(x,E)?α, where E is a closed set in X and $alpha in mathbb {R}$ . We... 相似文献
469.
Leskinen Anumaija Salminen-Paatero Susanna Räty Antti Tanhua-Tyrkkö Merja Iso-Markku Taneli Puukko Esa 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(1):399-413
Journal of Radioanalytical and Nuclear Chemistry - Determination of 14C, 55Fe, 63Ni and gamma emitters in two different types of activated reactor pressure vessel (RPV) steel samples were carried... 相似文献
470.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献