Chemical transformations of 2,4-diaryl-2,3-dihydro-1H,1,5-benzodiazepines

The behavior of 2,4-diphenyl-2,3-dihydro-1H-1,5-benzodiazepine in acylation, alkylation, nitrosation, oxidation, reduction, salt formation, and opening of the diazepine ring under the influence of various dinucleophiles and acids was studied. It is shown that the dihydrodiazepine ring is extremely sensitive to acidic reagents and undergoes rearrangement to an imidazole ring under their influence. The structure of the cis- and trans-tetrahydroazepines were analyzed thoroughly.Translated from Khimiya Geterotsiklicheskikl Soedinenii, No. 6, pp. 830–836, June, 1982.     

Quantum Zeno and anti-Zeno paradoxes

Continuous observation of a time independent projection operator is known to prevent change of state (the quantum Zeno paradox). We discuss the recent result that generic continuous measurement of time dependent projection operators will in fact ensure change of state: an anti-Zeno paradox.     

Cyclocondensation of 3-Amino-1,2,4-triazoles with Esters of Substituted Cinnamic Acids and Aromatic Unsaturated Ketones

We have studied the reactions of 3-amino, 3,5-diamino-, and 3-amino-5-trifluoromethyl-1,2,4-triazole with esters of substituted cinnamic acids and aromatic unsaturated ketones; we have established the directionality of formation of the tetrahydrooxopyrimidine ring. We have carried out hydrolysis and hydrazinolysis of 7-phenyl-4,5,6,7-tetrahydro-1,2,4-triazolo[1,5-a]pyrimidin-5-one. We have conducted an X-ray diffraction study of isopropylidene hydrazide of 3-(5-amino-1,2,4-triazol-1-yl)-3-phenylpropionic acid.     

Microwave‐Assisted and Ultrasonic‐Assisted Three‐Component Heterocyclization of 4‐Amino‐5‐carboxamido‐1,2,3‐triazole,Thiopyran‐3‐one‐1,1‐dioxide,and Aromatic Aldehydes

Three‐component heterocyclization of 4‐amino‐5‐carboxamido‐1,2,3‐triazole, thiopyran‐3‐one‐1,1‐dioxide, and aromatic aldehydes under ultrasonic and microwave irradiation was studied. Regardless of the reaction parameters, 5,6,7,9‐tetrahydro‐4H‐thiopyrano[3,2‐d][1,2,3]triazolo[1,5‐a]pyrimidine‐8,8‐dioxides were isolated as sole reaction products whose structures were proven with help of NMR data and X‐ray analysis.     

Three component condensation of 3-amino-1,2,4-triazole with carbonyl compounds. A new synthesis of 1,2,4-triazolo[1,5-a]pyrimidines

Three component condensation of 3-amino-1,2,4-triazole with an aromatic aldehyde and ketone gives 1,2,4-triazolo[1,5-a]-pyrimidines. An x-ray structural investigation of 5-phenyl-4,5,6,7-tetrahydro-1,2,4-triazolo[1,5-a]benzo[h]quinazoline was undertaken in order to determine the course of this reaction.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 481–485, April, 1993.     

粉粒体两相流的电容层析成象测量

粉粒体系统中的固相浓度分布的在线测量是十分困难的问题．电容层析成象技术是一种近年来发展起来的非侵入式快速浓度场测量技术．它不干扰流场，不受流动中颗粒浓度、加速度、不透明等因素的制约．本文讨论其测量原理、应用、近期进展、存在的主要问题及其解决的对策．     

ac Conductivity of mixed spinel NiAl0.7Cr0.7Fe0.6O4

ac Conductivity measurements are carried out across the metal to insulator transition in NiAl_0.7Cr_0.7Fe_0.6O₄. The low frequency data is analyzed using Summerfield scaling theory for hopping conductivity. The exponent of the scaling behavior has significantly different values in the conducting and insulating regimes. The hopping frequency and the zero frequency conductivity are found to increase with temperature, slowly in the metallic regime and rapidly in the insulating regime.     

Synthesis and Crystal Structure of 3-Carbamoyl-6-methyl-5-phenylcarbamoyl-2-thioxo-1,2,3,4-tetrahydropyridine-4-spirocyclohexane

3-Carbamoyl-6-methyl-5-phenylcarbamoyl-2-thioxo-1,2,3,4-tetrahydropyridine-4-spirocyclohexane has been synthesized by the condensation of cyclohexylidenecyanothioacetamide with acetoacetanilide and piperidine. The structure of the product was established by X-ray structural analysis.