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21.
Summary A volumetric method has been developed for the determination of thorium salts with Titriplex III (disodium EDTA) using a mixture of ferrous salt and cacotheline as indicator. The titration of the thorium salt is carried out in a buffered solution ofph 2.72 in carbon dioxide atmosphere with magnetic stirring until a pink color appears. The reduction of cacotheline to the pink compound occurs only when all the thorium is complexed by EDTA. The end point is sharp and the method has been found to give results accurate to 0.2 to 0.3%. Ferric iron, zirconium and phosphates are found to interfere while ferrous iron does not interfere. Walpole sodium acetate-HCl buffers are to be employed since phosphate-citrate buffers interfere, due to the presence of phosphate and citrate.In conclusion one of us, Mr. V. Narayana Rao, desires to express his grateful thanks to the Ministry of Education, Government of India, for the award of Senior Research Fellowship which has enabled him to take part in this investigation. 相似文献
22.
Biju Mathew B. Narayana B. Muralidhara Rao C. H. Raghavan Nambiar B. Ramachandra 《Mikrochimica acta》1996,122(3-4):295-299
A simple and accurate complexometric method is proposed for the determination of Tl(III) using semicarbazide hydrochloride as a releasing agent. In the presence of diverse metal ions, thallium is complexed first with a known excess of EDTA, and the surplus EDTA is then titrated with standard zinc sulfate at pH 5.0–6.0 (hexamine) using xylenol orange indicator. An excess of 5% aqueous neutral solution of semicarbazide hydrochloride is then added and the released EDTA is titrated against standard zinc sulfate solution. The method works well in the range 2–50 mg of Tl(III) with relative errors < 0.5%, standard deviations 0.05mg and coefficient of variation 0.4%. The method is applied for the determination of thallium content in complexes and alloy compositions 相似文献
23.
D. Indumathi M. V. N. Murthy V. Ravindran 《Zeitschrift fur Physik C Particles and Fields》1992,56(3):427-436
Following recent interest in the subject of polarisation phenomena, we discuss the cross-sections and polarisation asymmetry in 2-jet production in polarised proton-polarised proton (
) scattering. We set up a complete set of parametrisations for the proton spin-dependent parton densities and use them to demonstrate that this cross-section is dominated by gluonic terms. Hence, a measurement of the asymmetry in such processes will provide information on the gluon spin-dependent density. We further show that a factorisation of the hadronic cross-section a la Combridge and Maxwell's work in unpolarised 2-jet production also applies to the spin-dependent case. Hence, the cross-section can be written in terms of a genericpolarised parton density, which can then be measured in the process. 相似文献
24.
Lawan Ly Xiaoqian Cheng Saravana R. K. Murthy Olivia Z. Jones Taisen Zhuang Steven Gitelis Alan T. Blank Aviram Nissan Mohammad Adileh Matthew Colman Michael Keidar Giacomo Basadonna Jerome Canady 《Molecules (Basel, Switzerland)》2022,27(13)
Soft tissue sarcomas (STS) are a rare and highly heterogeneous group of solid tumors, originating from various types of connective tissue. Complete removal of STS by surgery is challenging due to the anatomical location of the tumor, which results in tumor recurrence. Additionally, current polychemotherapeutic regimens are highly toxic with no rational survival benefit. Cold atmospheric plasma (CAP) is a novel technology that has demonstrated immense cancer therapeutic potential. Canady Cold Helios Plasma (CHCP) is a device that sprays CAP along the surgical margins to eradicate residual cancer cells after tumor resection. This preliminary study was conducted in vitro prior to in vivo testing in a humanitarian compassionate use case study and an FDA-approved phase 1 clinical trial (IDE G190165). In this study, the authors evaluate the efficacy of CHCP across multiple STS cell lines. CHCP treatment reduced the viability of four different STS cell lines (i.e., fibrosarcoma, synovial sarcoma, rhabdomyosarcoma, and liposarcoma) in a dose-dependent manner by inhibiting proliferation, disrupting cell cycle, and inducing apoptosis-like cell death. 相似文献
25.
The basic principle for the production of polarised thermal neutrons is discussed and the choice of various crystal monochromators
surveyed. Brief mention of broad-spectrum polarisers is made. The application of polarised neutrons to the study of magnetisation
density distributions in magnetic crystals, the dynamic concept of polarisation, principle and use of polarisation analysis,
the neutron spin-echo technique are discussed. 相似文献
26.
27.
A simple method for the synthesis of amines by the reduction of imines, anils and enamines, including some chiral substrates, with the MCl2/NaBH4/CH3OH reagent (M = Co, Ni) in 64–82% yields is described. 相似文献
28.
Konkala Karnakar Katla Ramesh Sabbavarapu Narayana Murthy Yadavalli Venkata Durga Nageswar 《Helvetica chimica acta》2013,96(12):2276-2281
The first example of the stereoselective synthesis of (Z)‐ and (E)‐allyl aryl sulfides and selenides from Baylis? Hillman acetates under neutral conditions in H2O by supramolecular catalysis involving β‐cyclodextrin is reported. β‐Cyclodextrin can be recovered and reused. The reaction is very efficient in providing allyl aryl sulfides and selenides in good‐to‐excellent yields with clean reaction profiles under mild reaction conditions. 相似文献
29.
A. Babulreddy R. V. Hymavathi Md. Manzoor Hussain G. Narayana Swamy 《Journal of heterocyclic chemistry》2013,50(3):727-733
A new class of methyleneamine‐linked bis‐heterocycles that exhibit antimicrobial activity was synthesized. Bromination of 1 followed by condensation with thiourea gave 3 . The reaction of 3 with propargyl bromide in dry toluene under inert atmosphere led to the formation of 4 . Its subsequent reaction with different nitrile oxides using CuSO4.5H2O–sodiumascorbate system in a 2:1 mixture of water and tert‐butyl alcohol yielded the title compounds 6a , 6b , 6c , 6d , 6e , 6f , 6g , 6h , 6i , 6j , 6k , 6l in good yields. The identities of these compounds were confirmed following elemental analysis, IR, 1H, 13C NMR, and mass spectral studies. All the title compounds exhibited pronounced in vitro antibacterial and antifungal activities. 相似文献
30.
Reaction of 2-pyridylmagnesium chlorides with N,N-dialkyl arylamides afford exclusively 2-(aroyl) pyridines in high yields and purity without the formation of any tertiary alcohol. This method employs easily available raw materials and avoids the use of hazardous lithium reagents and cryogenic conditions. Further, preferential reactivity of this Grignard reagent with N,N-dialkyl arylamides over its carbonitrile counterparts offers a variety of 2-(aroyl) pyridines including the ones containing carbonitrile groups on the aryl ring. 相似文献