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51.
For scalar diffusion models with unknown drift function asymptotic equivalence in the sense of Le Cam's deficiency between
statistical experiments is considered under long-time asymptotics. A local asymptotic equivalence result is established with
an accompanying sequence of simple Gaussian shift experiments. Corresponding globally asymptotically equivalent experiments
are obtained as compound experiments. The results are extended in several directions including time discretisation. An explicit
transformation of decision functions from the Gaussian to the diffusion experiment is constructed.
The authors acknowledge the financial support provided through the European Community's Human Potential Programme under contract
HPRN-CT-2000-00100, DYNSTOCH 相似文献
52.
Beatriz Veleirinho Manuel F. Rei J. A. Lopes‐DA‐Silva 《Journal of Polymer Science.Polymer Physics》2008,46(5):460-471
This study describes the preparation and characterization of nanofibrous mats obtained by electrospinning poly(ethylene terephthalate) (PET) solutions in trifluoroacetic acid/dichloromethane (TFA/DCM). Special attention was paid to the effect of polymer concentration and solvent properties on the morphology, structure, and mechanical and thermal properties of the electrospun nonwovens. The results show that the spinnable concentration of PET solution in TFA/DCM solvents is above 10 wt %. Mats have nanofibrous morphology with fibers having an average diameter in the range of 200–700 nm (depending on polymer concentration and solvent composition) and an interconnected pore structure. Higher solution concentration favors the formation of uniform fibers without beads and with higher diameter. Morphology and fiber assembly changed with the solvent properties. Solvent mixtures rich in TFA, i.e., those with higher dielectric constant and lower surface tension, originated fibers with small diameter. However, due to the lower volatility, those solvent mixtures also produced more branched and crosslinking fibers, with less morphologic uniformity. Mechanical properties (Young's modulus, ultimate strength, and elongation at break) and thermal properties (glass transition, crystallization, and melting) have been studied for the PET electrospun nanomats and compared with those of the original polymer. Solvent effect on fiber crystallinity was not significant, but a complex effect was observed on the mechanical properties of the electrospun mats, as a consequence of the different structural organization of the fibers within the mat network. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 460–471, 2008 相似文献
53.
Takayuki Kawashima Rei Okazaki Renji Okazaki 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》1997,109(22):2609-2612
54.
Three pyridoxine derivatives have been isolated from the fresh stem bark of Albizzia julibrissin DURAZZ.. One of them, named julibrin II, was found to exhibit arrhythmic-inducing action. However, neither the others having the same aglycone nor some glycosides having the same sugar unit showed the action. 相似文献
55.
Catalytic property for the electro-oxidation of cysteine (RSH) on modified glassy carbon electrode with octkis(benzylthio)tetraazaporphyrinato cobalt(Ⅱ)[abbr.Co(Ⅱ)OBTP] has been studied, substantial catalytic effect has been observed. Tafel slope plot gives 121 mV/decade. The reaction order are 1 for RSH; -1 for H+ (in acid solution) and 0 (in base solution). Possible mechanism of the reaction was proposed. 相似文献
56.
Dr. Baolin Wang Dr. Yongxin Li Dr. Rakesh Ganguly Prof. Dr. Richard D. Webster Prof. Dr. Rei Kinjo 《Angewandte Chemie (International ed. in English)》2018,57(26):7826-7829
One‐electron oxidation of 1,4,2,5‐diazadiborinine 1 has been studied. While the reaction of 1 a bearing phenyl groups on the B atoms with AgAl{OC(CF3)3}4 afforded a complex mixture, the same oxidation reaction with 1 b featuring bulky mesityl substituents on the B atoms rendered the corresponding cation radical 2 b as an isolable species. X‐ray diffraction analysis, EPR spectroscopy, and DFT calculations of 2 b revealed the delocalization of the unpaired electron over the entire π‐system of 2 b , as well as a large spin density (0.76 in total) on the two equivalent boron atoms. The chemical trapping reaction of 2 b with p‐benzoquinone and triphenyltin hydride afforded the dicationic species 3 containing two newly formed B?O bonds and the monocationic product 2b‐H containing a B?H bond, respectively, thus confirming the boron‐centered radical reactivity of 2 b . 相似文献
57.
58.
A new oleanene glucuronide called melilotus-saponin O2 (1) was isolated together with three known ones (soyasaponin I, astragaloside VIII, wistariasaponin D) from the aerial parts of Melilotus officinalis (L.) Pallas (Leguminosae). The structure of 1 was determined to be 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl- (1-->2)-beta-D-glucuronopyranosyl melilotigenin by spectroscopic and chemical methods. 相似文献
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