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41.
A novel technique of measuring a magnetic Compton profile using the grazing angle geometry against a sample surface (Grazing Incidence Magnetic Compton Profile) has been successively developed. Measurements of a magnetic moment and a magnetic Compton profile are possible for a Fe 200 nm film on a thick glass substrate. The estimated thinnest limit for measurements is 100 nm for a Fe film.  相似文献   
42.
P-Chirogenic trialkylphosphonium salts were prepared from the corresponding free phosphines by treatment with a strong acid (HBF4 or HOTf). No racemization of the phosphonium salts occurred in methanol or water even at considerably high temperature. The salts were conveniently used in rhodium-catalyzed asymmetric hydrogenation of enamides.  相似文献   
43.
Dihydroboronium derivatives of (S,S)-1,2-bis(t-butylmethylphosphino)ethane (t-Bu-BisP*) were prepared and used as chiral diphosphine ligand precursors in Rh-catalyzed asymmetric hydrogenation of methyl (Z)-acetamidocinnamate to afford the hydrogenation product in up to 94% enantioselectivity.  相似文献   
44.
The unit distance graphE n is the graph whose vertices are the points in Euclideann-space, and two vertices are adjacent if and only if the distance between them is 1. We prove that for anyn there is a finite bipartite graph which cannot be embedded inE n as an induced subgraph and that every finite graph with maximum degreed can be embedded inE N ,N=(d 3d)/2, as an induced subgraph.  相似文献   
45.
The purpose in this paper is to prove that there exists a lattice on certain solvable Lie groups and to construct a symplectic solvmanifold with the Hard Lefschetz property, and a locally conformal Kähler solvmanifold. We see that minimal models for these solvmanifolds are formal.  相似文献   
46.
The aim of this paper is to characterize the nuclearity of an integral operator, defined by a continuous non-negative definite square integrable kernel on a separable metric space, in terms of the integrability of the trace of the kernel function. Nuclearity here plays a role forU-statistics.  相似文献   
47.
48.
An investigation was made of the gelation of dimethacrylate‐type crosslinking agents in view of an application for separation media. The study mainly centered on a crosslinking agent, glycerol dimethacrylate (GDMA), which is relatively hydrophilic because of a hydroxyl group in the middle of its structure. The gelation of GDMA was compared with that of other hydrophobic crosslinking agents such as ethylene glycol dimethacrylate and 1,6‐hexanediol dimethacrylate. The diluents used in the study were toluene, toluene with methanol, and cyclohexanol. The gelation was observed in real time with a charge coupled device camera and dynamic light scattering (DLS). Also, the separated dry gels were extensively characterized with scanning electron microscopy, BET (N2 absorption and desorption isotherm), and Fourier transform infrared. DLS analysis showed a stronger molecular interaction of GDMA gelation in toluene, whereas this interaction was much weaker in an alcoholic solvent such as toluene with methanol or cyclohexanol. This indicated that GDMA gelation might proceed through hydrogen bonding as well as a crosslinking reaction of vinyl groups. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 949–958, 2006  相似文献   
49.
Two kinds of new glycopolymers, (P(VB‐1‐GlcaH‐co‐AAm), 9 ) and (P(VB‐1‐Glco‐co‐AAm), 10 ), were synthesized through the radical copolymerization of styrene derivatives bearing pendant D ‐glucaric and D ‐gluconic moieties, N‐(p‐vinylbenzyl)‐1‐D ‐glucaramide (VB‐1‐GlcaH, 7 ), and N‐(p‐vinylbenzyl)‐D ‐gluconamide (VB‐1‐Glco, 8 ), with acrylamide (AAm). Glycopolymer 9 bearing the pendant glucaric moiety at the first position inhibited the hydrolysis of a model compound for xenobiotics‐β‐glucuronide conjugates, p‐nitrophenyl β‐D ‐glucuronide, uncompetitively, in contrast to the competitive inhibition in the presence of the corresponding isomeric glycopolymer bearing the pendant D ‐glucaric unit at the sixth position (P(VB‐6‐GlcaH‐co‐AAm), 3 ) reported in our previous article. On the other hand, another copolymer 10 bearing the gluconic moiety was found not to inhibit the hydrolysis as well as the corresponding copolymer bearing pendant gulonic unit (P(VB‐6‐Glco‐co‐AAm), 4 ). These results indicate that the hydrolysis is influenced not only by existence of pendant carboxyl units but also by the direction on the linkage of the glyco‐units to the polymer frame. Therefore the configurational position of hydroxy groups in pendant glyco‐units in macromolecular inhibitors may be essential for the interaction with β‐glucuronidase. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4895–4903, 2006  相似文献   
50.
A simple and highly sensitive spectrophotometric method for the determination of anthracycline anticancer agents, such as Daunorubicin hydrochloride (DAU), was established by using aluminum(III) and Chromazurol S (CAS) in a nonionic surfactant micellar medium. In the case of determination of DAU, the apparent molar absorptivity was 1.3 x 10(5) dm3 mol(-1) cm(-1) at 615 nm. Beer's law was obeyed in the concentration range of 0.028 - 2.82 microg ml(-1) for DAU. Owing to no need for solvent extraction, this method could be applied to assays of DAU and related drugs in pharmaceutical preparations.  相似文献   
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