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41.
The mixed complexes of Eu(III) with succinate (succ2?) and malonate (mal2?) and ethylenediamine (en) have been studied polarographically at 25°C and at constant ionic strength, μ = 0.1 (NaNO3) and pH 6. The reduction of the complexes in each case is quasi-reversible and diffusion-controlled. In each system three mixed complexes are formed, viz. [Eu(succ)(en)]+, [Eu(succ)(en)2]+ and [Eu(succ)2(en)]? with stability constants log β11 = 9.2, log β12 = 17.5 and log β21 = 11.7; and [Eu(mal)(en)]+, [Eu(mal)2(en)2]? and [Eu(mal)3(en)]3? with stability constants log β11 = 11.4, log β22 = 19.08 and log β31 = 13.5 respectively. 相似文献
42.
N. T. Madhu P. K. Radhakrishnan Edna Williams W. Linert 《Journal of Thermal Analysis and Calorimetry》2005,79(1):157-161
The phenomenological, kinetic and mechanistic aspects of the nitrate, chloride, bromide and iodide complexes of cobalt(II) with 4-N-(4-antipyrylmethylidene)aminoantipyrine (AA) have been studied by TG and DTG techniques. The kinetic parameters such as activation energy, pre-exponential factor and entropy of activation were computed. The rate controlling process at all stages of decomposition is random nucleation with one nucleus on each particle (Mampel model) 相似文献
43.
N. Shashank Vikram Singh Sanjeev K. Gupta K. V. Madhu J. Akhtar R. Damle 《辐射效应与固体损伤》2013,168(4):313-322
Ni/SiO2/Si MOS structures were fabricated on n-type Si wafers and were irradiated with 50 MeV Li3+ ions with fluences ranging from 1×1010 to 1×1012 ions/cm2. High frequency C–V characteristics are studied in situ to estimate the build-up of fixed and oxide charges. The nature of the charge build-up with ion fluence is analyzed. Defect levels in bulk Si and its properties such as activation energy, capture cross-section, trap concentration and carrier lifetimes are studied using deep-level transient spectroscopy. Electron traps with energies ranging from 0.069 to 0.523 eV are observed in Li ion-irradiated devices. The dependence of series resistance, substrate doping and accumulation capacitance on Li ion fluence are clearly explained. The study of dielectric properties (tan δ and quality factor) confirms the degradation of the oxide layer to a greater extent due to ion irradiation. 相似文献
44.
Rachel K. Kalaimani Madhu N. Belur Sivaramakrishnan Sivasubramanian 《Linear algebra and its applications》2013
In this paper we assume dynamical systems are represented by linear differential-algebraic equations (DAEs) of order possibly higher than one. We consider a structured system of DAEs for both the to-be-controlled plant and the controller. We model the structure of the plant and the controller as an undirected and bipartite graph and formulate necessary and sufficient conditions on this graph for the structured controller to generically achieve arbitrary pole placement. A special case of this problem also gives new equivalent conditions for structural controllability of a plant. Use of results in matching theory, and in particular, ‘admissibility’ of edges and ‘elementary bipartite graphs’, make the problem and the solution very intuitive. Further, our approach requires standard graph algorithms to check the required conditions for generic arbitrary pole placement, thus helping in easily obtaining running time estimates for checking this. When applied to the state space case, for which the literature has running time estimates, our algorithm is faster for sparse state space systems and comparable for general state space systems. 相似文献
45.
An analysis of phase-modulated heteronuclear dipolar decoupling sequences in solid-state nuclear magnetic resonance 总被引:1,自引:1,他引:0
Thakur RS Kurur ND Madhu PK 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2008,193(1):77-88
The design of variants of the swept-frequency two-pulse phase modulation sequence for heteronuclear dipolar decoupling in solid-state NMR is reported, their performance evaluated, and compared with other established sequences like TPPM and SPINAL. Simulations performed to probe the role of the homonuclear (1)H-(1)H bath show that the robustness of the decoupling schemes improves with the size of the bath. In addition, these simulations reveal that the homonuclear (1)H-(1)H bath also leads to broad baselines at high MAS rates. Results from a study of the SPINAL decoupling scheme indicate that optimisation of the starting phase and phase increment improves its performance and efficiency at high MAS rates. Additionally, experiments performed on a liquid crystal display the role of the initial phase in SPINAL-64 and sequences in the SW(f)-TPPM family. 相似文献
46.
Agarwal Madhu Kuldeep Brijesh John Annie P. Maheshwari Karishma Dohare Rajeev 《Journal of Thermal Analysis and Calorimetry》2022,147(13):7243-7252
Journal of Thermal Analysis and Calorimetry - In this study, beeswax is studied as a phase change material (PCM) to store heat due to its high latent heat. The disadvantages of using beeswax were... 相似文献
47.
48.
Das Madhu Sudan Samanta Anu Sanyal Sourish Mandal Sanjoy 《Wireless Personal Communications》2021,120(4):3389-3413
Wireless Personal Communications - Mobile robot navigation has been a current issue in the most recent two decades. Mobile robots are necessary to explore in obscure and dynamic situations. To... 相似文献
49.
Sakram B. Madhu P. Sonyanaik B. Rambabu S. Ravi D. Kurumanna A. 《Russian Journal of General Chemistry》2018,88(6):1224-1227
Russian Journal of General Chemistry - A new methodology has been developed for the synthesis of novel 2-oxo-1,2-dihydro-1,8-naphthyridine-3-carboxylates from 2-aminonicotinaldehyde,... 相似文献
50.
Dr. Madhu Sheri Dr. Umesh Choudhary Dr. Sunitha Grandhee Prof. Todd Emrick 《Angewandte Chemie (International ed. in English)》2018,57(17):4599-4602
We report a fluoride‐catalyzed deblocking of urethanes as “blocked” isocyanates. Organic and inorganic sources of fluoride ion proved effective for deblocking urethanes and for converting polyurethanes to small molecules. Distinct from conventional deblocking chemistry involving organometallic compounds and high temperatures, the method we describe is metal‐free and operates at or slightly above room temperature. The use of fluorescent blocking agents enabled visual and spectroscopic monitoring of blocking/deblocking reactions, and the selected conditions proved applicable to urethanes containing a variety of blocking groups. The method additionally enabled a one pot deblocking and polymerization with α,ω‐diols. Overall, this deblocking/polymerization strategy offers a convenient and efficient solution to problems that have limited the breadth of applications of polyurethane chemistry. 相似文献