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51.
P. S.R. Murthy K. R. Priolkar P. A. Bhobe A. Das P. R. Sarode A. K. Nigam 《The European Physical Journal B - Condensed Matter and Complex Systems》2010,78(3):275-282
Effect of Co, Ru and Cu substitution at B and B’ sites on the magnetic and transport properties of LaSrCoRuO6
have been investigated. All the doped compositions crystallize in the monoclinic structure in the space group
P21/n indicating a double perovskite structure. While the magnetization and conductivity increase in Co and Ru
doped compounds, antiferromagnetism is seen to strengthen in the Cu doped samples. These results are explained on
the basis of a competition between linear Co-O-Ru-O-Co and perpendicular Co-O-O-Co antiferromagnetic interactions
and due to formation of Ru-O-Ru ferromagnetic networks. 相似文献
52.
A study of the chemical ionization (CI) and collisional activation (CA) spectra of a number of α, β-unsaturated nitriles has revealed that the even-electron ions such as [MH]+ and [MNH4]+ produced under chemical ionization undergo decomposition by radical losses also. This results in the formation of M +˙ ions from both [MH]+ and [MNH4]+ ions. In the halogenated molecules losses of X˙ and HX compete with losses of H˙ and HCN. Elimination of X˙ from [MH]+ is highly favoured in the bromoderivative. The dinitriles undergo a substitution reaction in which one of the CN groups is replaced with a hydrogen radical and the resulting mononitrile is ionized leading to [M ? CN + 2H]+ under CI(CH4) or [M ? CN + H + NH4] and [M ? CN + H + N2H7]+ under CI(NH3) conditions. 相似文献
53.
D. I. Naiduss W. W. Kiesewetter S. L. Dikanskaja J. Schapiro R. Meurice J. Cartiaux E. F. Posorski G. N. Murthy S. Mihaéloff A. D. Rich J. J. Vollertsen Gh. Ghimicescu G. Kotsis C. T. Townsend J. A. Esty F. C. Baselt R. Dubrisay J. Gascon E. R. Scheggia K. M. Renner E. S. Miller C. A. Mitchell A. G. Sossin und S. E. Spektor 《Fresenius' Journal of Analytical Chemistry》1939,118(1-2):48-51
Ohne Zusammenfassung 相似文献
54.
S. Chandrasekhar Mrunal Pendke Chandrashekar Muththe Srirama Murthy Akondi Prathama S. Mainkar 《Tetrahedron letters》2012,53(10):1292-1295
A straight forward entry to α,α-dideutero-β-amino esters starting from the corresponding imines and deuterated acetonitrile has been developed involving a two-step process. 相似文献
55.
In this paper, four nanofiltration membranes, viz., (1) coating of N,O-carboxymethyl chitosan (NOCC) on polyethersulfone ultrafiltration (PES UF) substrate membrane; (2) chitosan and acrylonitrile butadiene styrene (ABS) in the blend ratio of 0:100 (ABS); (3) diethylenetriamine pentaacetic acid coating via casting method on PES UF substrate membrane (DC50); and (4) NOCC and cellulose acetate (CA) polymer blend solution (0.4?wt%) coated on a glass plate (NOCC?CCA), were selected from our previous work. By using these membranes, separation behaviour of mercury and chromium ions was studied at different operating conditions from their salt solutions. From the experimental data, it is evident that ABS membrane gave highest observed solute rejection (92.88 and 88.67?% for 10?ppm feed concentration of mercury sulphate?Cwater system and chromium sulphate?Cwater system, respectively) and NOCC?CCA membrane gave highest permeate volume flux. But from the rejection as well as permeate volume flux point of view, NOCC?CPES membrane is considered to be the best choice among all the membranes. 相似文献
56.
Synthesis of 6‐Fluoro‐7‐cyclic Amino‐substituted Dicarboxylic Acid Quinolones and their Antibacterial Activity 下载免费PDF全文
A. Ravi Kumar G. Sathaiah A. Chandra Shekhar K. Raju P. Shanthan Rao B. Narsaiah Y. Kanaka Raju U. S. N. Murthy V. Srimai M. Ramesh T. Parthasarathy 《Journal of heterocyclic chemistry》2014,51(Z1):E114-E122
Novel 1‐carboxymethyl‐6‐fluoro‐7‐cyclic amino‐substituted‐4‐oxo‐1,4‐dihydroquinolone‐3‐carboxylic acids 7a , 7b , 7c , 7d , 7e , 7f , 7g , 7h , 7i , 7j , 7k , 7l , 7m , 7n were synthesized as a new class of quinolones. Ethyl‐6‐fluoro‐7‐chloro‐1,4‐dihydro‐4‐quinoline‐3‐carboxylic acid was prepared from conventional method and reacted with ethyl bromoacetate to furnish N‐carboxymethyl derivatives. The compounds were screed against various Gram‐positive and Gram‐negative bacterial strains. Antibacterial activity data is validated by molecular docking studies. 相似文献
57.
The synthesis and characterization of five homologous series of symmetrical compounds composed of banana-shaped molecules containing a biphenyl moiety are reported. All these compounds are non-Schiff's bases and are esters. The effects of lateral substituents such as fluoro, methyl and ethyl in the side arms of these molecules are examined. These substituents have a strong influence in reducing the clearing temperatures. Banana phases such as B1, B2 and B6 were observed in the above series of compounds. The mesophases were characterized by a combination of polarizing optical microscopy, differential scanning calorimetry, X-ray diffraction and electro-optic studies. 相似文献
58.
In this paper we study a policy for servicing items sold with warranty. We obtain the optimal policy to minimize the expected warranty cost per unit sold. 相似文献
59.
Polycyclic aromatic hydrocarbons (PAHs), apart from their carcinogenic and mutagenic nature, create many problems in the petrochemical industry due to their tendency toward carbonization. Compounds in C8 aromatic isomer feed are analyzed by means of sample concentration, followed by separation of individual compounds by gas chromatography on a stainless steel OV-101 phase capillary column and identification by gas chromatography/mass spectrometry and gas chromatography/Fourier transform infrared spectroscopy. Various compounds belonging to different classes (mainly monocyclic, dicyclic, and tricyclic aromatics), oxygenated aromatics, and aliphatic saturates are quantified in the concentrated hydrocarbon residue of C8 isomer feed. Both unsubstituted and alkyl substituted ring type compounds are present. Concentrations obtained for PAH compounds in the C8 isomer feed range from 0.2 to 0.42 micrograms/mL. 相似文献
60.