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241.
A simple and very fast photometric method for the determination of trace levels of cerium(IV) has been developed. Use has been made of the reaction in which iron (II), on oxidation with cerium(IV), gives iron(III) which is complexed with tiron, in acidic medium, to form a stable blue color, the intensity of which is in direct proportion to the amount of cerium(IV) originally present in the sample solution. In addition, the method has a wide range of determination and reasonable sensitivity, and it avoids both temperature control and the tedious extraction step. 相似文献
242.
A cluster of many small holes with negative imaginary surface impedances may generate a negative refraction index 下载免费PDF全文
Ahmed Alsaedi Bashir Ahmad Durga Prasad Challa Mokhtar Kirane Mourad Sini 《Mathematical Methods in the Applied Sciences》2016,39(13):3607-3622
We deal with the scattering of an acoustic medium modeled by an index of refraction n varying in a bounded region Ω of and equal to unity outside Ω. This region is perforated with an extremely large number of small holes Dm's of maximum radius a, a << 1, modeled by surface impedance functions. Precisely, we are in the regime described by the number of holes of the order M:=O(aβ ? 2), the minimum distance between the holes is d ~ at, and the surface impedance functions of the form λm~λm,0a?β with β > 0 and λm,0 being constants and eventually complex numbers. Under some natural conditions on the parameters β,t, and λm,0, we characterize the equivalent medium generating approximately the same scattered waves as the original perforated acoustic medium. We give an explicit error estimate between the scattered waves generated by the perforated medium and the equivalent one, respectively, as a→0. As applications of these results, we discuss the following findings:
243.
Qureshi Nawab Muhammad Faseeh Siddiqui Isma Farah Abbas Asad Bashir Ali Kashif Nam Choon Sung Chowdhry Bhawani Shankar Uqaili Muhammad Aslam 《Wireless Personal Communications》2021,116(2):1217-1229
Wireless Personal Communications - Big data analytics has addressed many in-place and remote network issues in a sub-aqueous distributed computing environment. Recently, a new phenomenon is... 相似文献
244.
Rahul Ashiqur Rahman Sabuj Saifur Rahman Akbar Md. Sajid Jo Han-Shin Hossain Md Akbar 《Wireless Networks》2021,27(1):475-493
Wireless Networks - Unmanned aerial vehicle (UAV) is a promising technology to serve as a mission-critical communication, where human operation or intervention is risky, dangerous, impossible or... 相似文献
245.
This paper investigates some new existence results for an nth-order nonlinear differential equation with four-point nonlocal integral boundary conditions (strip/slit like conditions). Our results are based on some standard fixed point theorems and Leray-Schauder degree theory. 相似文献
246.
247.
Various semiprime rings with less than 2w elements are shown to be slender 相似文献
248.
Qureshi Nawab Muhammad Faseeh Siddiqui Isma Farah Unar Mukhtiar Ali Uqaili Muhammad Aslam Nam Choon Sung Shin Dong Ryeol Kim Jaehyoun Bashir Ali Kashif Abbas Asad 《Wireless Personal Communications》2019,106(4):2225-2236
Wireless Personal Communications - Big data analytics has simplified processing complexity of large dataset in a distributed environment. Many state-of-the-art platforms i.e. smart grid has adopted... 相似文献
249.
Mushtaq Sajid Choi Mi Hee Yang Jung Eun Shim Ha Eun Song Lee Song Ha Yeon Choi Yong Jun Jeon Jongho 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(2):997-1003
Journal of Radioanalytical and Nuclear Chemistry - We herein report a convenient radiolabeling method capable of real-time in vivo imaging and biodistribution of bacteria in a living subject.... 相似文献
250.
Tian-Lu Ren Bao-Hua Xu Sajid Mahmood Ming-Xue Sun Suo-Jiang Zhang 《Tetrahedron》2017,73(20):2943-2948
A protocol for the cobalt-catalyzed oxidative esterification of allylic/benzylic C(sp3)–H bonds with carboxylic acids was developed in this work. Mechanistic studies revealed that C(sp3)–H bond activation in the hydrocarbon was the turnover-limiting step and the in-situ formed [Co(III)]Ot-Bu did not engage in hydrogen atom abstraction (HAA) of a C–H bond. This protocol was successfully incorporated into a synthetic pathway to β-damascenone that avoided the use of NBS. 相似文献