Дослідження моделі зміни стану дренажного штреку за умов надробки в шахтах Західного Донбасу

The influence of extracting works on the overlying layers to drainage drift is investigated. The regularities of the stresses distribution in overworking conditions for development working allowing amend used fastening system to improve the efficiency of working support is identified.Исследовано влияние очистных работ по вышележащему пласту на дренажный штрек. Выявлены закономерности распределения напряжений в условиях надработки подготовительной выработки, позволяющие внести изменения в используемую систему крепления, для повышения эффективности поддержания выработки.Досліджено вплив очисних робіт по вищерозміщеному пласту на дренажний штрек. Виявлені закономірності розподілу напружень в умовах надпрацювання підготовчої виробки, що дозволяють внести зміни в використовувану систему кріплення, для підвищення ефективності підтримки виробки

1-Methyl(benzyl)-2,5-dimethyl-4-N-[aryl(alkyl)amino]piperidines and their acyl derivatives

N-Substituted γ-aminopiperidines and their benz- and propioamides have been synthesized from γ-piperidones. The stereoisomeric amines and amides have been separated and identified. © 1988 Plenum Publishing Corporation

Peculiarities of the three-dimensional structures of isomers of 1,2,5-trimethyl-4-amino(amido)piperidines from the 1H and 13C NMR spectra

The three-dimensional structures of seven 1,2,5-trimethyl-4-amino(amido)piperidines were studied by means of the 1H and 13C NMR spectra. The 3JHH values and the 13C chemical shifts indicate that the substituents in the piperidine ring of all of the 2c,5c,4r isomers have a 2e,4e,5a orientation, while those in the piperidine ring of all of the 2c,5t,4r isomers have a 2e,4e,5e orientation. The conformational change (as a result of ring conversion) 2e,4a,5e → 2a,4e,5a was observed for the 2t,5c,4r isomers on passing from the corresponding amine to the amide; this change is associated with striving of the more bulky amide substituent to become equatorially oriented. Retarded rotation about the C(4)-N bond was observed in the 2c,5t,4r isomer of the 4-(N-phenylbenzamido) derivative; this is explained by steric hindrance due to the 5e-CH3 group. © 1988 Plenum Publishing Corporation

1-Methyl(benzyl)-2,5-dimethyl-4-N-[aryl(alkyl)amino]piperidines and their acyl derivatives

N-Substituted γ-aminopiperidines and their benz- and propioamides have been synthesized from γ-piperidones. The stereoisomeric amines and amides have been separated and identified. © 1988 Plenum Publishing Corporation

Peculiarities of the three-dimensional structures of isomers of 1,2,5-trimethyl-4-amino(amido)piperidines from the 1H and 13C NMR spectra

The three-dimensional structures of seven 1,2,5-trimethyl-4-amino(amido)piperidines were studied by means of the 1H and 13C NMR spectra. The 3JHH values and the 13C chemical shifts indicate that the substituents in the piperidine ring of all of the 2c,5c,4r isomers have a 2e,4e,5a orientation, while those in the piperidine ring of all of the 2c,5t,4r isomers have a 2e,4e,5e orientation. The conformational change (as a result of ring conversion) 2e,4a,5e → 2a,4e,5a was observed for the 2t,5c,4r isomers on passing from the corresponding amine to the amide; this change is associated with striving of the more bulky amide substituent to become equatorially oriented. Retarded rotation about the C(4)-N bond was observed in the 2c,5t,4r isomer of the 4-(N-phenylbenzamido) derivative; this is explained by steric hindrance due to the 5e-CH3 group. © 1988 Plenum Publishing Corporation