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H. F. Wiebe D. R. Harper L. Holborn F. Henning H. L. Callendar E. H. Griffiths C. W. Waidner G. K. Burgess A. L. Day R. B. Sosman L. H. Adams J. Johnston G. Moeller F. Hoffmann W. Meissner J. G. L. Stern Th. W. Richards R. C. Wells W. Meissner Th. W. Richards F. G. Jackson C. Kellner H. F. Wiebe P. Hebe P. Hebe und M. Freund 《Fresenius' Journal of Analytical Chemistry》1913,52(5):304-308
Ohne Zusammenfassung 相似文献
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M. Rohmer G. Rollin L. A. Youtz H. Causse H. W. Rowell J. v. Ferentzy J. A. Muller A. Fraenkel J. Fasal S. W. Young F. Ibbotson H. Brearley A. Gibb L. B. Skinner R. H. Hawley Th. Brown E. D. Campbell E. C. Champion J. S. C. Wells H. Angenot S. Burman Dinan A. G. Levy G. Lunge H. Mastbaum R. Job J. P. Pattinson H. S. Pattinson 《Analytical and bioanalytical chemistry》1907,46(10-11):722-737
637.
J. Mitchell Wells Gavin E. Reid Brian J. Engel Peng Pan Scott A. McLuckey 《Journal of the American Society for Mass Spectrometry》2001,12(7):873-876
Electrochemical reduction of the iron bound in the heme group of cytochrome c is shown to occur in the nano-electrospray capillary if the protein is sprayed from neutral water using a steel wire as the electrical contact. Quadrupole ion trap collisional activation is used to study the dissociation reactions of cytochrome c as a function of the oxidation state of the iron. Oxidized (Fe(III)) cytochrome c dissociates via sequence-specific amide bond cleavage, while the reduced (Fe(II)) form of the protein dissociates almost exclusively by loss of protonated heme. Apo-cytochrome c, from which the heme has been removed either via gas-phase dissociation of the reduced holo-protein or via solution chemistry, dissociates via amide bond cleavage in similar fashion to the oxidized holo-protein. 相似文献
638.
Weijun Ye Sharon Wells Joseph M. DeSimone 《Journal of polymer science. Part A, Polymer chemistry》2001,39(21):3841-3849
Well‐defined D ‐glucose‐containing glycopolymers, poly(3‐O‐methacryloyl‐1,2 : 5,6‐di‐O‐isopropylidene‐D ‐glucofuranose) (PMAIpGlc), and diblock copolymers of PMAIpGlc with poly(1,1‐dihydroperfluorooctyl methacrylate) (PFOMA) were synthesized by living anionic polymerization in THF at ?78 °C with 1,1‐diphenylhexyllithium in the presence of lithium chloride. The resulting polymers were found to possess predictable molecular weights and very narrow molecular weight distributions (MWD, Mw/Mn ≤ 1.16). Removal of the acetal protective groups from the protected glycopolymer block copolymer was carried out using 90% trifluoroacetic acid at room temperature, yielding a hydrophilic block copolymer with pendant glucose moieties. Both protected (lipophilic/CO2‐philic) and deprotected (hydrophilic/CO2‐philic) fluorocopolymers were proved to be CO2 amphiphiles. Their solubility in CO2 was heavily influenced by the amphiphilic structure, such as the copolymer compositions and the polarities of sugar block. Light‐scattering studies showed that, after removal of the protective groups, the deprotected block copolymer formed aggregate structures in liquid CO2 with an average micellar size of 27 nm. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3841–3849, 2001 相似文献
639.
Chuong V. Nguyen Thien D. Nguyen John C. Wells Akihiko Nakayama 《Experiments in fluids》2010,48(4):577-587
PIV measurements near a wall are generally difficult due to low seeding density, low velocity, high velocity gradient, and
strong reflections. Such problems are often compounded by curved boundaries, which are commonly found in many industrial and
medical applications. To systematically solve these problems, this paper presents two novel techniques for near-wall measurement,
together named Interfacial PIV, which extracts both wall-shear gradient and near-wall tangential velocity profiles at one-pixel
resolution. To deal with curved walls, image strips at a curved wall are stretched into rectangles by means of conformal transformation.
To extract the maximal spatial information on the near-wall tangential velocity field, a novel 1D correlation function is
performed on each horizontal pixel line of the transformed image template to form a “correlation stack”. This 1D correlation
function requires that the wall-normal displacement component of the particles be smaller than the particle image diameter
in order to produce a correlation signal. Within the image regions satisfying this condition, the correlation function yields
peaks that form a tangential velocity profile. To determine this profile robustly, we propose to integrate gradients of tangential
velocity outward from the wall, wherein the gradient at each wall-normal position is measured by fitting a straight line to
the correlation peaks. The capability of Interfacial PIV was validated against Particle Image Distortion using synthetic image
pairs generated from a DNS velocity field over a sinusoidal bed. Different velocity measurement schemes performed on the same
correlation stacks were also demonstrated. The results suggest that Interfacial PIV using line fitting and gradient integration
provides the best accuracy of all cases in the measurements of velocity gradient and velocity profile near wall surfaces. 相似文献
640.
In this paper we study the algebraic structure of the space of compactly supported orthonormal wavelets over real numbers. Based on the parameterization of wavelet space, one can define a parameter mapping from the wavelet space of rank 2 (or 2-band, scale factor of 2) and genus gto the (g−1) dimensional real torus (the products of unit circles). By the uniqueness and exactness of factorization, this mapping is well defined and one-to-one. Thus we can equip the rank 2 orthogonal wavelet space with an algebraic structure of the torus. Because of the degenerate phenomenon of the paraunitary matrix, the parameterization map is not onto. However, there exists an onto mapping from the torus to the closure of the wavelet space. And with such mapping, a more complete parameterization is obtained. By utilizing the factorization theory, we present a fast implementation of discrete wavelet transform (DWT). In general, the computational complexity of a rank morthogonal DWT is O(m2g). In this paper we start with a given scaling filter and construct additional (m−1) wavelet filters so that the DWT can be implemented in O(mg). With a fixed scaling filter, the approximation order, the orthogonality, and the smoothness remain unchanged; thus our fast DWT implementation is quite general. 相似文献