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排序方式: 共有197条查询结果,搜索用时 31 毫秒
161.
Divakar Viswanath. 《Mathematics of Computation》2000,69(231):1131-1155
For the familiar Fibonacci sequence (defined by , and for ), increases exponentially with at a rate given by the golden ratio . But for a simple modification with both additions and subtractions - the random Fibonacci sequences defined by , and for , , where each sign is independent and either or - with probability - it is not even obvious if should increase with . Our main result is that
with probability . Finding the number involves the theory of random matrix products, Stern-Brocot division of the real line, a fractal measure, a computer calculation, and a rounding error analysis to validate the computer calculation.
162.
Smetanin M Viswanath RN Kramer D Beckmann D Koch T Kibler LA Kolb DM Weissmüller J 《Langmuir : the ACS journal of surfaces and colloids》2008,24(16):8561-8567
We report a cantilever bending investigation into the variation of surface stress, f, with surface charge density, q, for (111)-textured thin films of gold in aqueous NaF and HClO 4. The graphs of f(q) are highly linear, and the surface stress-charge coefficients, d f/d q, are -1.95 V for 7 mM NaF and -2.0 V for 10 mM HClO 4 near the potential of zero charge. These values exceed some previously published experimental data by a factor of 2, but they agree with recent ab initio calculations of the surface stress-charge response of gold in vacuum. 相似文献
163.
A stereoselective approach to polyhydroxylated L-Choi derivatives has been developed. The oxidative cyclization of L-tyrosine was optimized to avoid partial racemization and to allow a more efficient scale-up. 相似文献
164.
Experiments have been carried out investigating the effectiveness of steady tangential blowing (inside the separation bubble)
to control an axisymmetric separated flow at low speeds. Turbulent boundary separation was induced on a contoured afterbody
and the separated shear layer reattached on a narrow cylindrical sting. Measurements made consisted of model surface pressures,
mean velocity, turbulent shear stress and kinetic energy profiles using a 2-component LDV system. The results explicitly demonstrate
that blowing downstream of the separation location, but within the bubble, can be an effective means of separation control,
considering both wall and wake flow reversals.
Received: 16 October 1998/Accepted: 27 September 1999 相似文献
165.
Lakshmi C. Kasi Viswanath Sengodan Senthil 《Molecular Crystals and Liquid Crystals》2017,656(1):12-21
A series of symmetrical chiral, liquid crystal dimeric molecules possessing ester- linked, biphenyl-naphthyl cores with varied spacer lengths and terminal vinyl groups have been synthesized using Naproxen as the synthetic precursor. The synthesized symmetrical chiral dimers were characterized by 1H NMR spectroscopy, and their liquid crystalline behavior was confirmed by DSC and HOPM studies. Structural effects on the mesomorphic and physicochemical properties were investigated in terms of variation of chiral chain length. The synthesized dimeric compounds exhibited SmX*, SmC*, SmA*, N*, BPI*, and BPII* mesophase sequences. An odd-even effect was observed in the dimers and the duration of the mesophase decreased with increasing spacer length. The synthesized vinyl substituted liquid crystalline dimers are particularly useful in understanding liquid crystal polymorphism and act as model compounds for liquid crystal polymers. 相似文献
166.
Gajavalli Kasi Mikaelian Georges Barrachin Marc Decreton Alexandre Fischer Evelyne Rogez Jacques Benigni Pierre 《Journal of Thermal Analysis and Calorimetry》2019,135(4):2209-2219
Journal of Thermal Analysis and Calorimetry - An Ag–Cd–In alloy is used as the control rod material in most pressurized water reactors. Despite this important application, the phase... 相似文献
167.
Reddy Ganji Sreekanth Rao Anna Venkateswara Keshavulu Masula Viswanath I. V. Kasi Laxminarayana Eppakayala 《Russian Journal of General Chemistry》2022,92(9):1749-1760
Russian Journal of General Chemistry - A series of novel fluoroquinolone thiazolidinone derivatives were synthesized and evaluated for their biological activity. All the newly synthesized compounds... 相似文献
168.
Gandikota N. Murthy Bolla R. Sekhar Bandyopadhyay A. Viswanath I. V. Kasi 《Russian Journal of Organic Chemistry》2019,55(8):1197-1203
Russian Journal of Organic Chemistry - The exocyclic C=C double bond in phenacylideneoxindole and 2-oxoacenaphthen-1-ylidene ketone derivatives has been selectively reduced in good yields with a... 相似文献
169.
170.