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排序方式: 共有825条查询结果,搜索用时 31 毫秒
1.
Vieira Renata Leia Demario Gaglieri Caroline de Oliveira Cristina Soltovski Ferreira Laura Teófilo Schnitzler Egon Bannach Gilbert 《Journal of Thermal Analysis and Calorimetry》2021,144(3):689-697
Journal of Thermal Analysis and Calorimetry - Buckwheat starch is an alternative source to supply the high global demand for starch. The properties of starch can be modified through chemical and... 相似文献
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3.
H. William Bosch Sre
o D. kapin Egon Matijevi 《Colloids and surfaces. A, Physicochemical and engineering aspects》2004,250(1-3):43-50
Controlled precipitation of the diagnostic imaging agent ethyl 3,5-di(acetylamino)-2,4,6-triiodobenzoate has been used to produce fine particles of various sizes, morphologies, and degrees of crystallinity, which depended on experimental conditions. In addition, two distinct polymorphic forms of the drug have been fully characterized by single crystal X-ray diffraction studies, and evidence for a third polymorph was also observed. Some of the so prepared dry particles were coated with a thin layer of silica. 相似文献
4.
The chemical mechanism of the precipitation of lead titanium peroxohydroxide particles in a solution of nitrilotriacetate (NTA) complexes of lead and titanium peroxo-hydroxide is envisioned as the interaction between cations of lead hydroxide and anions of polymeric titanium peroxo-hydroxide. 相似文献
5.
F. Herfurth K. Blaum S. Eliseev O. Kester H.-J. Kluge S. Koszudowski C. Kozhuharov G. Maero D. Neidherr W. Quint S. Schwarz S. Stahl G. Vorobjev 《Hyperfine Interactions》2006,173(1-3):93-101
A decelerator will be installed at GSI in order to provide and study heavy nuclei without or with only few electrons at very
low energies or even at rest. Highly-charged ions will be produced by stripping at relativistic energies. After electron cooling
and deceleration in the Experimental Storage Ring (ESR) the ions are ejected out of the storage ring at 4 MeV/u and further
decelerated in a combination of linear accelerator structures operated in reverse. Finally, they are injected into a Penning
trap where the ions are cooled to 4 K by electron cooling in combination with resistive cooling. From here, the ions can be
transferred in a quasi DC or in a pulsed mode to different experimental setups. This article describes the technical concepts
of this project focused on the Penning trap.
相似文献
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We investigate which types of asymptotic distributions can be generated by the knots of convergent sequences of interpolatory integration rules. It will turn out that the class of all possible distributions can be described exactly, and it will be shown that the zeros of polynomials that are orthogonal with respect to varying weight functions are good candidates for knots of integration rules with a prescribed asymptotic distribution.Research supported by the Deutsche Forschungsgemeinschaft (AZ: Sta 299/4-2). 相似文献
8.
Herbert Stahl 《Constructive Approximation》1989,5(1):221-240
Letf be an analytic function with all its singularities in a compact set \(E_f \subset \bar C\) of (logarithmic) capacity zero. The function may have branch points. The convergence of generalized (multipoint) Padé approximants to this type of function is investigated. For appropriately selected schemes of interpolation points, it is shown that close-to-diagonal sequences of generalized Padé approximants converge in capacity tof in a certain domain that can be characterized by the property of the minimal condenser capacity. Using a pole elimination procedure, another set of rational approximants tof is derived from the considered generalized Padé approximants. These new approximants converge uniformly on a given continuum \(V \subset \bar C\backslash E_f\) with a rate of convergence that has been conjectured to be best possible. The continuumV is assumed not to divide the complex plane. 相似文献
9.
The Pd(OAc)2/O2/DMSO catalyst system displays impressive versatility in the aerobic oxidation of organic substrates, ranging from alcohols to olefins. This report details mechanistic insights into these reactions. Dimethyl sulfoxide (DMSO) plays no redox role in the chemistry, and kinetic experiments identify the turnover-limiting step as DMSO-promoted oxidation of palladium(0) by molecular oxygen. The "chemical oxidase" pathway characterized for this catalyst system holds great promise for the design of new aerobic oxidation reactions. 相似文献
10.
Losses of H2 and H2O from the [M-H]? alkoxide anions of 1,4-cyclohexanediol formed in OH? negative chemical ionization were studied using synthetic deuterated analogues and labelling by hydrogen-deuterium exchange between neutrals in the ion source prior to ionization. Simple 1,2-H2 elimination leading to an enolate ion does not occur, but stereospecific mechanisms are shown to give a ketolate intermediate daughter ion. Collisionally activated dissociation spectra of the resulting daughter ions are the same as those of the corresponding ions generated directly from ketols. 相似文献