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111.
112.
Specimens of iron-doped indium oxide (In1-xFex)2O3 with x?=?0.015, 0.03, 0.045 and 0.06, amalgamated through a traditional solid-state reaction method followed by H2/air sintering, were characterised using an X-ray diffractometer (XRD), a vibrating sample magnetometer (VSM), and a scanning electron microscope (SEM) to investigate their structural, magnetic and morphological properties respectively. According to XRD plots, all the specimens exhibit cubic bixbyite structures along with ancillary phases. Magnetic assessment showed that In2O3 has a negative susceptibility, exhibiting diamagnetic behaviour at room temperature. The doping of Fe ions induces ferromagnetic (FM) ordering, which is enhanced with increasing doping content. The strength of the magnetisation increases when the specimens are exposed to H2 but is reduced on further air sintering. A bound magnetic polaron (BMP) model is successfully fitted to the observed FM data involving localised carriers and magnetic cations. A multivariate assessment viz. a hierarchical cluster analysis (HCA) was used to corroborate and strengthen the experimental determined magnetic properties. A homogeneous particle distribution was observed in all SEM micrographs and is validated through MATLAB-based simulation by applying a watershed segmentation algorithm. Surface plots also confirm the change in magnetic properties with increase in doping concentration. 相似文献
113.
Arulraj Ruba A. Gajjela Raju Chauthe Siddheshwar Kisan Bagadi Muralidhararao Mathur Arvind 《Chromatographia》2022,85(6):497-506
Chromatographia - In drug discovery environment, determination of residual solvents is indispensable and requires rapid analysis covering a maximum number of commonly used solvents especially with... 相似文献
114.
Bob Boyd Gareth Brenton Eddie Clayton Jonathan Curtis R. M. Elliott G. A. Errock B. N. Green R. H. Bateman Simon J. Gaskell Iwan Griffiths Zdenek Herman Philip Jonathan Rich Kondrat Mila Laušević Chris Lock Deepak Mathur John F. J. Todd Károly Vékey 《Rapid communications in mass spectrometry : RCM》2016,30(11):1253-1264
115.
Kumar Namrata Vijayshankar Soumya Pasupathi Pranav Nirmal Kumar Sundaramoorthy Elangovan Poonguzhali Rajesh Mathur Tamilarasan Krishnamurthi 《Research on Chemical Intermediates》2018,44(9):5403-5417
Research on Chemical Intermediates - In this research, soda lignin was extracted from Bambusa bambos using a soda pulping process, and interaction effects of pulping variables were statistically... 相似文献
116.
Ananta Karmakar Mushkin Basha G.T. Venkatesh Babu Murali Botlagunta Noormohamed Abdul Malik Richard Rampulla Arvind Mathur Arun Kumar Gupta 《Tetrahedron letters》2018,59(48):4267-4271
A number of cyanomethyl esters of natural/unnatural aminoacids with un-protected amino functionality were synthesized because of their synthetic and medicinal importance. Critical N-Boc deprotection methods in the presence of labile (hydrolytic sensitivity) cyanomethyl functionality were screened thoroughly and it was found that readily available 4M HCl in 1,4-dioxane solution (2–4 equiv); acetonitrile, 0?°C, 2–4?h was a suitable condition. This condition was generalized and successfully applied to a variety of alkyl, alkynyl, aryl, heteroaryl, benzyl, azido, spiro amino acid cyanomethylesters irrespective of the nature of the amine (primary or secondary) and the distance between the amine and ester group to achieve final deprotected amino esters with high yield, and purity compared to other commonly known N-protecting groups (Cbz, Fmoc, Ac, Bn, Bz etc.). It was also demonstrated that N-Boc protected aminoacid cyanomethylesters are stable enough to carry out further functionalization compared to N-unprotected counterparts. 相似文献
117.
dc conductivity as a function of temperature has been measured for as-evaporated and annealed films of amorphous Si, grown by the vacuum evaporation technique. The experimental data suggest that conduction in the higher temperature range (~175–300 K) is by the thermally activated holes in the localized states near the valence band edge while conduction in the lower temperature range (~77–175 K) is found to be thermally assisted tunnelling in the localized states near the Fermi level. The activation energy for both the processes is found to increase with an increase in the annealing temperature. The average hopping distance, calculated for conduction near the Fermi level, is also found to increase with an increase in the annealing temperature. 相似文献
118.
In this paper a compact low profile elliptical fractal patch antenna for high gain and multiband is presented which resembles Lorentz fractal shape. By introducing fractal on ellipse patch multiband applications are achieved. With the help of CST Microwave Studio Suite TM the proposed structure has been designed and analyzed. The simulated results are confirmed experimentally. The suggested antenna has a dimension of 40?×?55 mm2 (L?×?W) and resonant frequencies obtained are 1.7, 3.2, 3.9, 5.9, 7.8, 8.6, 9.7, 11.4 and 12.6 GHz with VSWR?≤?2. The aerial is assembled on FR-4 (εr?=?4.4) substrate with thickness of substrate 1.6 mm. This antenna holds applications in many satellite communication transmissions, some Wi-Fi devices, cordless telephones, and weather radar systems. 相似文献
119.
Yu. V. Torubaev A. A. Pasynskii P. Mathur 《Russian Journal of Coordination Chemistry》2008,34(11):799-804
A reaction of the tetramer [PhTeI]4 with Fe(CO)5 gave the monomeric complex (CO)3FeI2(Ph2Te2) (I) containing a diphenyl ditelluride molecule linked with cis-tricarbonyldiiodoiron. According to X-ray diffraction data, the Fe-Te distance in complex I (2.5724(6) ?) is appreciably shorter than the sum of the covalent Fe and Te radii and the Te-Te bond (2.7705(5) ?) is only
slightly longer than that in free Ph2Te2 (2.705(1) ?). In the reaction of Fe(CO)5 with PhTeI3, a complex with PhTeI as a ligand to the transition metal atom was obtained for the first time. Unlike free PhTeI, the resulting
complex (CO)3FeI2(PhTeI) (II) is stable in air at room temperature for several days. According to X-ray diffraction data, the ligand PhTeI (Te-C 2.126(4)
?, Te-I(3) 2.7548(5) ?) is stabilized by the coordination of tellurium to both the iron (Te-Fe 2.5451(6) ?) and iodine atoms
(Te(1)-I(1) 3.1634(5) ?). The latter coordination probably involves the vacant d orbital of tellurium and the lone electron pair on the iodide ligand.
Original Russian Text ? Yu.V. Torubaev, A.A. Pasynskii, P. Mathur, 2008, published in Koordinatsionnaya Khimiya, 2008, Vol.
34, No. 11, pp. 807–811. 相似文献
120.
Upadhyay SK Tehlan S Mathur P 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,66(2):347-352
A new benzimidazole-based diamide ligand-N,N'-bis(alanine-2-benzimidazolyl) hexanediamide (ABHA) has been synthesized and utilized to prepare Cu(II) complexes of general composition [Cu(ABHA)X2].nH2O,where X is an exogenous anionic ligand (X=Cl-,NO3-). Low temperature EPR spectra has been obtained that shows gparallel>gperpendicular>2.0024, indicating a tetragonal geometry in the solution state. The complexes display a quasi-reversible redox wave due to the Cu(II)/Cu(I) reduction process. E1/2 values shift anodically as NO3-相似文献