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1.
2.
Ohne ZusammenfassungÜbersetzt von Dr. K. Jäckel, Marburg/L.Wir danken Herrn Prof. N. R. Dhar D.Sc. (London und Paris), F.R.I.C., F.N.I., I.E.S. (Eetd) Direktor Shila Dhar Institut für Bodenkunde und Vorstand der Chemischen Abteilung, Universität Allahabad, für sein lebhaftes Interesse und seine Ratschläge für die Arbeit. 相似文献
3.
Swarup Narain Tewari 《Mikrochimica acta》1967,55(4):704-707
Summary A paper Chromatographic technique on salt-buffered papers for separating the alkaloids of opium has been devised. The method has been used for determining the origin of opium samples by studying the pattern of theR
f
values of the alkaloids present and the effect on it produced by the presence of various adulterants.
Zusammenfassung Die chromatographische Trennung der Opiumalkaloide auf gepuffertem Papier wurde beschrieben. Das Verfahren wurde zur Herkunftsbestimmung von Opiumproben auf Grund desR f -Musters der anwesenden Alkaloide benützt. Der Einfluß verschiedener Fälschungszusätze wurde untersucht.
Résumé Mise au point d'une technique de Chromatographie sur papier pour la séparation des alcaloïdes de l'opium, oú les papiers sont imprégnés des sels tampons. Utilisation de la méthode pour déterminer l'origine des échantillons d'opium en étudiant les valeurs duR f des alcaloïdes présents et l'effet produits sur celles-ci par la présence d'adultérants divers.相似文献
4.
M. M. Charyulu K. Venugopal Chetty D. G. Phal Veena Sagar SagarD. M. Sagar S. M. Pawar R. Swarup V. V. Ramakrishna V. Venugopal 《Journal of Radioanalytical and Nuclear Chemistry》2002,251(1):153-154
Recovery of americium from nitric acid solutions was studied by co-precipitation as hydroxide with various ions like calcium, ferric, nickel using sodium hydroxide and ammonium hydroxide. Studies were also carried out to recover americium using lanthanum fluoride and bismuth phosphate co-precipitation. All the methods are able to co-precipitate Am quantitatively. However, co-precipitation of Am with optimum concentration iron using ammonia is found to be better from nitric acid solutions containing large concentrations of calcium ions. Approximately 2 g of Am was recovered from 150 litres of solution batch wise using iron. 相似文献
5.
V. R. Bhandiwad Rajendra Swarup S. K. Patil 《Journal of Radioanalytical and Nuclear Chemistry》1979,52(1):5-14
The extraction of Np(IV), Pu(IV) and U(VI) from aqueous hydrochloric acid into quaternary amines has been studied. The dependence
of the distribution coefficient on amine concentration suggests that the actinide ions extracted are NpCl
6
2−
PuCl
6
2−
and UO2Cl
4
2−
. This is further supported by the absorption spectra of the amine extracts of these actinide ions. Based on the extraction
data obtained, a simple method for the separation of typical metal ions such as Cs, lanthanides and Zr from U(VI) and Pu(IV)
is suggested. 相似文献
6.
Pyrimido[4,5-d]pyrimidine derivatives 4 have been prepared in an efficient and regioselective manner in water via multi-component reaction of isothiocyanate 1, aromatic aldehyde 2, N,N-dimethyl-6-amino uracil 3 in the presence of p-toluenesulfonic acid (p-TSA) as a Lewis acid catalyst. 相似文献
7.
Srinivas Cheruku Chaithra Nagaraju Poornima Shetty Swarup Hassan A Sandhya Nagarakere C 《合成通讯》2020,50(10):1486-1494
AbstractWe have developed an economical and efficient method for the synthesis of medicinally and synthetically important indole-based triarylmethanes by using indoles and benzhydrols in the presence of propylphosphonic anhydride (T3P®). This methodology is an alternate approach for the C–C bond formation with good to excellent yields. In this T3P-mediated dehydration approach, the by-product is highly soluble in water, so that it can be done at larger scale also. In addition to that this efficient protocol has several advantages such as mild reaction conditions, short reaction time and operational simplicity. We have successfully synthesized pyrrole, imidazothiadiazole and imidazolo pyridine based triarylmethanes also. 相似文献
8.
In this paper, Mg-doped ZnO nanoparticles were synthesized by the facile sol–gel method. The crystalline structure, characteristic absorption bands and morphology of the obtained Mg-doped ZnO nanoparticles were studied by XRD, FTIR and TEM. The thermal degradation behaviour of the samples was investigated by differential scanning calorimetry (DSC) and thermogravimetry (TG). The effect of Mg concentrations and annealing temperatures on the antibacterial properties of the obtained nanoparticles was investigated in detail. The results indicated that doping Mg ions into ZnO lattice could enhance its antibacterial activity. Antibacterial assay demonstrated that Mg-doped ZnO with 7% Mg content annealed at 400 °C had the strongest antibacterial activity against Listeria monocytogenes (98.7%). This study indicated that the inhibition rate of ZnO nanoparticles increased with the formation of granular structure and the decrease of ZnO size due to the doping of Mg ions into the ZnO lattice. 相似文献
9.
This paper is concerned with torsion-free Kleinian groups that are generated by two parabolic transformations. Our main result
is that every such group of the second kind is geometrically finite; this is in response to a question raised by Riley. We
also show that in the natural one (complex) dimensional setting, the space of torsion-free Kleinian groups of the second kind
is path-connected.
The first author was supported in part by NSF Grant #8701774. 相似文献
10.
Amit M. Jabgunde Rahul S. Patil Swarup De Eveline Lescrinier Steven De Jonghe Leonid Beigelman Piet Herdewijn 《Tetrahedron》2019,75(8):1107-1114
The synthesis of 3′-fluoro-4′-amino-hexitol nucleosides with a uracil and cytosine nucleobase was performed. The synthesis started from 1,5:2,3-dianhydro-4,6-benzylidene-allitol and afforded the target compounds in 15 steps. These protected hexitol nucleosides are valuable building blocks for the preparation of a new class of oligonucleotides. 相似文献