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Chengzhong Cui Edward M. Bonder Frieder Jkle 《Journal of polymer science. Part A, Polymer chemistry》2009,47(23):6612-6618
A new class of amphiphilic organometallic block copolymers with cationic organoboron pendant groups was developed. Selective replacement of one of the bromine substitutents on each boryl group of the block copolymer PSBBr2‐b‐PS with an organometallic reagent ArM (ArM = 2,4,6‐trimethylphenyl copper, 4‐t‐butylphenyltrimethyl tin) followed by treatment with 2,2′‐bipyridine gave the novel block copolymers [ 3Ar ](Br)n as light yellow solid materials that show good stability in air and moisture and high solubility in most organic solvents. Their structure and composition were confirmed by multinuclear NMR, GPC, and elemental analysis. Highly regular micellar aggregates form in block‐selective solvents (e.g., MeOH, toluene) as demonstrated by 1H NMR, dynamic light scattering, and transmission electron microscopy. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6612–6618, 2009 相似文献
44.
This paper provides an analysis of the polynomiality of primal-dual interior point algorithms for nonlinear complementarity
problems using a wide neighborhood. A condition for the smoothness of the mapping is used, which is related to Zhu’s scaled
Lipschitz condition, but is also applicable to mappings that are not monotone. We show that a family of primal-dual affine
scaling algorithms generates an approximate solution (given a precision ε) of the nonlinear complementarity problem in a finite
number of iterations whose order is a polynomial ofn, ln(1/ε) and a condition number. If the mapping is linear then the results in this paper coincide with the ones in Jansen
et al., SIAM Journal on Optimization 7 (1997) 126–140.
Research supported in part by Grant-in-Aids for Encouragement of Young Scientists (06750066) from the Ministry of Education,
Science and Culture, Japan.
Research supported by Dutch Organization for Scientific Research (NWO), grant 611-304-028 相似文献
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Draganov D Wapenaar K Thorbecke J Nishizawa O 《The Journal of the Acoustical Society of America》2007,122(5):EL172-EL178
By crosscorrelating transmission recordings of acoustic or elastic wave fields at two points, one can retrieve the reflection response between these two points. This technique has previously been applied to measured elastic data using diffuse wave-field recordings. These recordings should be relatively very long. The retrieval can also be achieved by using deterministic transient sources with the advantage of using short recordings, but with the necessity of using many P-wave and S-wave sources. Here, it is shown how reflections were retrieved from the cross correlation of transient ultrasonic transmission data measured on a heterogeneous granite sample. 相似文献
48.
Diferrocenophosphaborin: A Planar‐Chiral,Redox‐Active and Anion‐Responsive Ambiphilic Ligand 下载免费PDF全文
Dr. Jiawei Chen Didier A. Murillo Parra Prof. Dr. Roger A. Lalancette Prof. Dr. Frieder Jäkle 《Angewandte Chemie (International ed. in English)》2015,54(35):10202-10205
A new class of Janus‐like ambiphilic ligands is introduced. The rigid diferrocene backbone in heterocycles 4‐SnP and 4‐BP creates an unprecedented chiral environment as demonstrated by multinuclear NMR and single‐crystal X‐ray studies. In addition, the ligands are redox‐responsive and the Lewis acidic borane moiety in 4‐BP can be exploited to further tune the properties: a clear decrease in the CO stretching frequency of a Vaska‐type RhI complex 5‐BP is observed upon addition of fluoride ions. Thus, the Lewis acid and Lewis base sites influence each other and their strength can be modulated by redox chemistry and anion binding. 相似文献
49.
We studied the flow fields generated inside sessile drops that oscillate periodically between states of high and low contact angle under the influence of alternating electric fields of variable frequency and amplitude. Following the motion of dye patches, we show that the number of oscillation cycles required to achieve mixing scales logarithmically with the Péclet number as expected for chaotic mixing. High speed movies reveal an asymmetry of the drop shape between the spreading and receding phase of the oscillations. This results in net internal flow fields that we characterize by tracing the motion of colloidal seed particles. The strength and frequency dependence of the flow are explained in terms of Stokes drift driven by capillary waves that emanate from the oscillating contact line. 相似文献
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