Some reactions of hydrazine with ruthenium compounds

1970 ◽  
Vol 48 (2) ◽  
pp. 351-355 ◽  
Author(s):  
F. Bottomley
Keyword(s):  
Alkaline Solution ◽  
Neutral Solution ◽  
Ammine Complexes ◽  
Ruthenium Compounds

Some reactions of hydrazine with pentachloroaquoruthenite(III) and ammine complexes of ruthenium(II) and ruthenium(III) have been investigated in acid, neutral, and alkaline solution. In neutral solution it has been shown that hydrazine monohydrochloride oxidized hexaammineruthenium(II) to hexaammineruthenium(III). In alkaline solution nitrogenpentaamrnineruthenium(II) was formed, and a mechanism for this reaction is postulated.

E.S.R. studies of the oxidative coupling of some bisphenols

1975 ◽  
Vol 28 (2) ◽  
pp. 343 ◽  
Author(s):  
SM Colegate ◽  
FR Hewgill ◽  
GB Howie
Keyword(s):  
Carbon Monoxide ◽  
Alkaline Solution ◽  
Unpaired Electron ◽  
Oxidative Coupling ◽  
Radical Anion ◽  
Neutral Solution

E.s.r. spectroscopy and the identification of products show that oxidation of 3,5,3?,5?-tetra-t-butyl-4,4?-dihydroxybenzophenone in neutral solution gives 3,5,3?,5?-tetra-t-butyldipheno-4,4?-quinone. If oxygen is present 2,6-di-t-butyl-p-benzoquinone is also formed. The evolution of carbon monoxide suggests that bis-spirodienones are intermediate in the formation of these products. E.s.r. spectra of radicals produced by oxidation of 3,5,3?,5?-tetra-t-butylbiphenyl-4,4?- dio and 2,6-di-t-butylhydro-quinone have been re-examined. In alkaline solution 3,5,3?,5?-tetra-t-butyl-4,4?-dihydroxybenzo-phenone is oxidized to a radical anion in which the unpaired electron is delocalized over both rings. ��� Attempts to detect unsymmetrical bisaryloxy radicals were unsuccessful, 3?,5?-di-t-butyl-4,4?-dihydroxy-3,5-dimethoxybenzophenone forming only the radical derived from the syringoyl portion, and 2,4?- oxydiphenol ether forming only the 4?-oxy radical. Comparison with the observation of both radicals when a mixture of guaiacol and p- methoxyphenol was oxidized suggests that C-O-C coupling in 2,4?- oxydiphenol proceeds by direct radical pairing.

THE MECHANISM OF THE ALCOHOLYSIS OF ALIPHATIC NITRITES: I. ALCOHOLYSIS OF 1-METHYLHEPTYL NITRITE IN ALKALINE AND NEUTRAL SOLUTION

1961 ◽  
Vol 39 (4) ◽  
pp. 940-946 ◽  
Author(s):  
A. D. Allen ◽  
G. R. Schonbaum
Keyword(s):  
Alkaline Solution ◽  
Reaction Rate ◽  
Ion Concentration ◽  
Neutral Solution ◽  
Neutral Reaction ◽  
Polarimetric Study ◽  
Kinetics Of ◽  
Asymmetric Carbon

A polarimetric study of the kinetics of the alcoholysis of 1-methylheptyl nitrite in alkaline solution has shown that the reaction rate is proportional to both the nitrite and alkoxide ion concentration. The asymmetric carbon center is not involved in the reaction. In strictly neutral solution no reaction occurs; the commonly observed "neutral" reaction is attributed to traces of acid formed in the decomposition of the nitrite ester. The mechanism of the reactions is discussed.

Photolysis of pyridinoline, a cross-linking amino acid of collagen, by ultraviolet light

1982 ◽  
Vol 60 (5) ◽  
pp. 525-529 ◽  
Author(s):  
Sachiko Sakura ◽  
Daisaburo Fujimoto ◽  
Kikuo Sakamoto ◽  
Akio Mizuno ◽  
Katsutoshi Motegi
Keyword(s):  
Amino Acid ◽  
Ultraviolet Light ◽  
Alkaline Solution ◽  
Absorption Maximum ◽  
Acidic Solution ◽  
Cross Linking ◽  
Neutral Solution ◽  
Pyridinium Ring ◽  
Optimum Wavelength ◽  
Amino Acid Analyser

Pyridinoline, a cross-linking amino acid of collagen, was degraded by irradiation of ultraviolet light. The decomposition rate varied with pH of the solution and wavelength of irradiation light. The maximum of the degradation rate at individual pH coincides with the ultraviolet absorption maximum. Namely, it was maximally degraded by irradiation at 295 nm in acidic solution and at 325 nm in neutral and alkaline solution. At the optimum wavelength, the photolysis occurred more rapidly in neutral and alkaline solution than in acidic solution. The quantum yield in neutral solution was approximately 0.11 and independent of wavelength. One of the photolysis products was identified as hydroxylysine on an amino acid analyser, indicating that the cleavage of the pyridinium ring occurred.

Electrodeposited palladium as efficient electrocatalyst for hydrazine and methanol electro-oxidation and detection

2021 ◽  
Author(s):  
Jelena Dušan Lović
Keyword(s):  
Cyclic Voltammetry ◽  
Alkaline Solution ◽  
Electrochemical Behavior ◽  
Electrocatalytic Activity ◽  
Differential Pulse ◽  
Pd Catalyst ◽  
Neutral Solution ◽  
Good Electrocatalytic Activity ◽  
Electro Oxidation ◽  
Pulse Voltammetry

Electrodeposited palladium was used as an electrocatalyst for electrochemical oxidation of hydrazine and methanol and the development of a sensitive platform for their detection. The electrochemical behavior of the electrode was evaluated by cyclic voltammetry (CV) while electroanalytical properties were determined by means of differential pulse voltammetry (DPV). The electrodeposited Pd catalyst exhibited good electrocatalytic activity towards the oxidation of hydrazine in neutral solution and methanol oxidation in alkaline solution. Under optimized DPV conditions, the electrodeposited Pd electrode shows good sensing capability in hydrazine and methanol detection.

scholarly journals Isolation and identification of products from alkylation of nucleic acids: ethyl- and isopropyl-purines

1975 ◽  
Vol 145 (1) ◽  
pp. 73-84 ◽  
Author(s):  
P D Lawley ◽  
D J Orr ◽  
M Jarman
Keyword(s):  
Mass Spectrometry ◽  
Nucleic Acids ◽  
Formic Acid ◽  
Absorption Spectra ◽  
Alkaline Solution ◽  
Alkylating Agents ◽  
Methyl Ethyl ◽  
Neutral Solution ◽  
Isolation And Identification ◽  
Methylating Agents

Ethylation and isopropylation of guanine in alkaline solution, or of adenine in formic acid, by alkyl methanesulphonates gave the following products: 1-, N2-, 3-, O6-, 7- and 9-alkylguanines; 1-, 3-, 7- and 9-alkyladenines. The products were identified from their characteristic u.v-absorption spectra, by comparison with either known ethyladenines or with the corresponding known methyladenines, and were also characterized by mass spectrometry. Their chromatographic properties on paper, t.l.c. and various columns were determined. DNA was alkylated in neutral solution with 14C-labelled alkyl methanesulphonates and the ratios of the alkylpurines formed were obtained, and compared for alkylation by methyl, ethyl and isopropyl methanesulphonates and by N-methyl-N-nitrosourea. The extents of alkylation at O-6 of guanine relative to those at N-7 of guanine varied with the reactivity of the methylating agents according to the predictions of Swain & Scott (1953) relating nucleophilicity of the groups alkylated with the substrate constants of the alkylating agents. The relative extents of alkylation at N-3 of adenine did not follow this correlation.

Clinical Evaluation of Radio-Labelled Bleomycin for Tumor Detection

1978 ◽  
Vol 17 (06) ◽  
pp. 238-248
Author(s):  
H. Beekhuis ◽  
M.A.P.C. van de Poll ◽  
A. Versluis ◽  
H. Jurjens ◽  
M.G. Woldring ◽  
...  
Keyword(s):  
Clinical Evaluation ◽  
Acidic Solution ◽  
Tumor Detection ◽  
Neutral Solution ◽  
Normal Tissues ◽  
Patients With Cancer ◽  
Tumor Bearing

Investigations with bleomycin labelled with radionuclides other than 57Co in patients with cancer and in tumor-bearing animals are described. In patients 57Co-bleo appears to be a better tumor-seeking radiopharmaceutical than 111In-bleo, 99mTc-bleo or 197Hg-bleo. This can be explained by a higher stability in vivo and a better tumor-seeking property of 57Co-bleo and less disturbing activity in the cardiac pool and in bone and other normal tissues when assessing the scintigram.Results with 111In-bleo labelled in acidic solution are not essentially different from those with 111In-bleo labelled in neutral solution.Results of 197Hg-bleo are almost identical with those of 197HgCl2 regarding the tumor-seeking effect as well as the distribution in normal tissues and organs. Probably the complex of 197Hg to bleomycin is not stable in vivo. The superiority of 57Co-bleo over 99mTc-bleo, 197Hg-bleo and also over 67Cu-bleo is confirmed by experiments on tumor bearing animals.We may conclude that the indication for use of bleomycin as a tumor-seeking pharmaceutical labelled with 111In, 99mTc, 197Hg or 67Cu seems to be very limited.

The Effect of Dry Mix Sodium Hydroxide onto Workability and Compressive Strength of Geopolymer Paste

2020 ◽  
Vol 12 (9) ◽  
Author(s):  
A. Z. Mohd Ali ◽  
◽  
N. A. Jalaluddin ◽  
N. Zulkiflee ◽  
◽  
...  
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Sodium Hydroxide ◽  
Sodium Silicate ◽  
Alkaline Solution ◽  
High Emission ◽  
New Material ◽  
Curing Regime ◽  
Solid Form ◽  
Geopolymer Paste

The production of ordinary Portland cement (OPC) consumes considerable amount of natural resources, energy and at the same time contribute in high emission of CO2 to the atmosphere. A new material replacing cement as binder called geopolymer is alkali-activated concrete which are made from fly ash, sodium silicate and sodium hydroxide (NaOH). The alkaline solution mixed with fly ash producing alternative binder to OPC binder in concrete named geopolymer paste. In the process, NaOH was fully dissolved in water and cooled to room temperature. This study aims to eliminate this process by using NaOH in solid form together with fly ash before sodium silicate liquid and water poured into the mixture. The amount of NaOH solids were based on 10M concentration. The workability test is in accordance to ASTM C230. Fifty cubic mm of the geopolymer paste were prepared which consists of fly ash to alkaline solution ratio of 1: 0.5 and the curing regime of 80℃ for 24 hours with 100% humidity were implemented. From laboratory test, the workability of dry method geopolymer paste were decreased. The compressive strength of the dry mix of NaOH showed 55% and the workability has dropped to 58.4%, it showed strength reduction compared to the wet mix method.

Chemical deposition of hard composite coatings Ni–Cu–P–Cr2O3

2020 ◽  
pp. 179-181
Author(s):  
A.A. Abrashov A.A. ◽  
E.G. Vinokurov ◽  
M.A. Egupova ◽  
V.D. Skopintsev
Keyword(s):  
Chromium Oxide ◽  
Alkaline Solution ◽  
Composite Coatings ◽  
Chemical Deposition ◽  
Alkaline Solutions ◽  
Functional Surface ◽  
Heat Treated ◽  
Weakly Acid Solution ◽  
Coating Composition ◽  
Weakly Acidic Solution

The technological (deposition rate, coating composition) and functional (surface roughness, microhardness) characteristics of chemical composite coatings Ni—Cu—P—Cr2O3 obtained from weakly acidic and slightly alkaline solutions are compared. It is shown that coatings deposited from slightly alkaline solution contain slightly less phosphorus and chromium oxide than coatings deposited from weakly acid solution (2...3 % wt. phosphorus and up to 3.4 % wt. chromium oxide), formed at higher rate (24...25 microns per 1 hour of deposition at temperature of 80 °C), are characte rized by lower roughness and increased microhardness. The Vickers microhardness at 0.05 N load of composite coatings obtained from slightly alkaline solution and heat-treated at 400 °C for 1 hour is 13.5...15.2 GPa, which is higher than values for coatings deposited made of weakly acidic solution. The maximum microhardness of coatings is achieved at concentration 20 g/l of Cr2O3 particles. The technology of chemical deposition of Ni—Cu—P—Cr2O3 coatings formed in slightly alkaline solution is promising for obtaining of materials with increased hardness and wear resistance.

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