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31.
C. F. Chan Man Fong 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1976,27(1):115-118
Summary It has been found that the effect of a radial temperature gradient on the Taylor stability problem for a viscoelastic fluid and for a Newtonian fluid is the same.
Résumé On montre que l'effet d'un gradient de la température radial sur le problème de stabilité de Taylor pour un fluide viscoélastique est semblable à celui d'un fluide Newtonien.相似文献
32.
Gordon PM Fong R Deb SK Li NS Schwans JP Ye JD Piccirilli JA 《Chemistry & biology》2004,11(2):237-246
The 2'-hydroxyl group contributes inextricably to the functional behavior of many RNA molecules, fulfilling numerous essential chemical roles. To assess how hydroxyl groups impart functional behavior to RNA, we developed a series of experimental strategies using an array of nucleoside analogs. These strategies provide the means to investigate whether a hydroxyl group influences function directly (via hydrogen bonding or metal ion coordination), indirectly (via space-filling capacity, inductive effects, and sugar conformation), or through interactions with solvent. The nucleoside analogs span a broad range of chemical diversity, such that quantitative structure activity relationships (QSAR) now become possible in the exploration of RNA biology. We employed these strategies to investigate the spliced exons reopening (SER) reaction of the group II intron. Our results suggest that the cleavage site 2'-hydroxyl may mediate an interaction with a water molecule. 相似文献
33.
Sidis Y Bourges P Fong HF Keimer B Regnault LP Bossy J Ivanov A Hennion B Gautier-Picard P Collin G Millius DL Aksay IA 《Physical review letters》2000,84(25):5900-5903
The influence of magnetic (S=1) and nonmagnetic (S=0) impurities on the spin dynamics of an optimally doped high temperature superconductor is compared in YBa2(Cu0.97Ni0.03)3O7 (Tc=80 K) and YBa2(Cu0.99Zn0.01)3O7 (Tc=78 K). In the Ni-substituted system, the magnetic resonance peak (which is observed at Er approximately 40 meV in the pure system) shifts to lower energy with a preserved Er/Tc ratio while the shift is much smaller upon Zn substitution. By contrast Zn, but not Ni, restores significant spin fluctuations around 40 meV in the normal state. These observations are discussed in the light of models proposed for the magnetic resonance peak. 相似文献
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Chun‐Guey Wu Ming‐I Lu Min‐Fong Jhong 《Journal of Polymer Science.Polymer Physics》2008,46(12):1121-1130
Organic soluble, oleic acid capped TiO2 nano‐rod was well‐mixed with the electrochromic polymer: Poly‐(4,4‐dioctylcyclopenta[2,1‐b:3,4‐b′]‐dithiophene (PDOCPDT) to form TiO2/PDOCPDT nanocompsoite. TiO2/PDOCPDT film showed high electrochemical stability and its coloration efficiency is 1.5 times of that for pure PDOCPDT. The function of TiO2 nano‐rods can be regarded as a dispersion agent. PDOCPDT chains in TiO2/PDOCPDT may have a less aggregated structure and more open morphology, therefore has higher coloration efficiency. TiO2 may also act as electron transport or temporary electron storage centers, electrons can be transferred reversibly between PDOCPDT and TiO2 nano‐rods. TiO2/PDOCPDT is well‐soluble in CHCl3, large area thin films can be fabricated reproducibly simply by spin coating. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1121–1130, 2008 相似文献
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High‐affinity aptamers for important signal transduction proteins, i.e. Cdc42‐GTP, p21‐activated kinase1 (PAK1) and MRCK (myotonic dystrophy kinase‐related Cdc42‐binding kinase) α were successfully selected in the low micro‐ to nanomolar range using non‐systematic evolution of ligands by exponential enrichment (SELEX) with at least three orders of magnitude enhancement from their respective bulk affinity of naïve DNA library. In the non‐SELEX procedure, CE was used as a highly efficient affinity method to select aptamers for the desired molecular target through a process that involved repetitive steps of partitioning, known as non‐equilibrium CE of equilibrium mixtures with no PCR amplification between successive steps. Various non‐SELEX conditions including the type, concentration and pH of the run buffer were optimized. Other considerations such as salt composition of selection buffer, protein concentration and sample injection size were also studied for high stringency during selection. After identifying the best enriched aptamer pool, randomly selected clones from the aptamer pool were sequenced to obtain the individual DNA sequences. The dissociation constants (Kd) of these sequences were in the low micromolar to nanomolar range, indicating high affinity to the respective proteins. The best binders were also subjected to sequence alignment to generate a phylogenetic tree. No significant consensus region based on approximately 50 sequences for each protein was observed, suggesting the high efficiency of non‐SELEX for the selection of numerous unique sequences with high selectivity. 相似文献
39.
Clifford W. Fong 《Journal of inclusion phenomena and macrocyclic chemistry》2017,89(3-4):343-351
It has been shown in this study that {CisPt@[n]CD} complexes formed from the anti-cancer drug cisplatin (CisPt) and cyclodextrins ([n]CD) can be a source of Pt based free radicals such as (H3N)2PtCl· and (H3N)2Pt·· species in water within a radiation environment which can produce hydrated electrons. Encapsulating CisPt within the [n]CD host takes advantage of the previously described drug delivery and reduced side effect advantages of CDs. Based on quantum mechanical modelling and literature results from other studies, it is predicted that {CisPt@[γ]CD} and the analogous 2-hydroxypropyl[β]cyclodextrin (HPBCD) complex {CisPt@HPBCD} may interact with serum albumin and engage in an enhanced permeation and retention mechanism in solid tumours, offering further synergistic advantages for radiation-{CisPt@[γ]CD} or -{CisPt@HPBCD} regimens over that of the conventional radiation-CisPt regimens in current use in anti-cancer chemoradiotherapies. Comparisons and possible advantages are made with the previously documented chemoradiosensitizing properties of the analogous cucurbit[7]uril based{CisPt@[7]CB} complex with the {CisPt@[γ]CD} and {CisPt@HPBCD} complexes suggest that all three complexes may have different and tailorable anti-tumour uses for a range of different chemotherapeutic environments or protocols. 相似文献
40.
In the present paper we describe surjective Lie and Jordan maps onto left ideals of prime noncommutative rings. Further, we describe bijective linear maps of left ideals of centrally closed prime algebras preserving commutativity. 相似文献