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1.
J Chromatogr A ; 1634: 461686, 2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-33220585

RESUMO

This work furthers the development of counter-current chromatography as an industrial separation process method. It was demonstrated that the industrial counter-current chromatography methods, in particular, for the separation groups of rare earth metals, can be implemented in a modified cascade of centrifugal mixer-settler extractors. The retention behavior of rare earth elements (samarium, europium, gadolinium, terbium, dysprosium and yttrium) on the pilot chromatographic unit consisting of 70 serially connected centrifugal mixer-settler extractors was experimentally studied under isocratic elution conditions using the mixture of 30 vol.% CyanexⓇ572 + 10 vol.% tributylphosphate in a hydrocarbon diluent as the stationary phase and aqueous nitric acid as the mobile phase. Theoretical analysis of experimental studies showed an acceptable agreement between the assumptions of the theory and experimental results.


Assuntos
Distribuição Contracorrente , Elementos da Série dos Lantanídeos/química , Elementos da Série dos Lantanídeos/isolamento & purificação , Disprósio/química , Disprósio/isolamento & purificação , Európio/química , Európio/isolamento & purificação , Gadolínio/química , Gadolínio/isolamento & purificação , Samário/química , Samário/isolamento & purificação , Térbio/química , Térbio/isolamento & purificação , Ítrio/química , Ítrio/isolamento & purificação
2.
Artigo em Russo | MEDLINE | ID: mdl-32119200

RESUMO

The decreasing of demographic security level is a global social economic trend in both developed and developing economies. Hence there is an urgent need in improving state social policy, including health care. The key target of this study is to evaluate the role of modern demographic trends in improving state social economic policy in health care. The study characterizes demography role in developing state health care strategy and to assesses world demographic trends that permitted to formulate potential barriers and obstacles in achieving stable level of demographic security. The distinctive features of modern demographic trends in Russia were identified and used as a background in developing prospective ways of improving state health policy in Russia with specific focusing on identified identified predicaments in national demographic development. The interdisciplinary analysis was applied in the field of theory and practice of health demography as a new scientific area as well as systemic and economic analysis. The most important result of the study was the established need in assessing relationship between current national demographic situation and economic efficiency and social economic consequences for whole society that actualized retrieval and elaboration of relevant social economic indices of life quality within the framework of health demography.


Assuntos
Política de Saúde , Dinâmica Populacional , Fatores Socioeconômicos , Demografia , Humanos , Estudos Prospectivos , Federação Russa
3.
Proc Math Phys Eng Sci ; 472(2195): 20160475, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27956876

RESUMO

We perform scanning tunnelling microscopy (STM) in a regime where primary electrons are field-emitted from the tip and excite secondary electrons out of the target-the scanning field-emission microscopy regime (SFM). In the SFM mode, a secondary-electron contrast as high as 30% is observed when imaging a monoatomic step between a clean W(110)- and an Fe-covered W(110)-terrace. This is a figure of contrast comparable to STM. The apparent width of the monoatomic step attains the 1 nm mark, i.e. it is only marginally worse than the corresponding width observed in STM. The origin of the unexpected strong contrast in SFM is the material dependence of the secondary-electron yield and not the dependence of the transported current on the tip-target distance, typical of STM: accordingly, we expect that a technology combining STM and SFM will highlight complementary aspects of a surface while simultaneously making electrons, selected with nanometre spatial precision, available to a macroscopic environment for further processing.

4.
Nanoscale ; 7(33): 14114-20, 2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-26243047

RESUMO

A hybrid graphene nematic liquid crystal (LC) light scattering device is presented. This device exploits the inherent poly-crystallinity of chemical vapour deposited (CVD) graphene films to induce directional anchoring and formation of LC multi-domains. This thereby enables efficient light scattering without the need for crossed polarisers or separate alignment layers/additives. The hybrid LC device exhibits switching thresholds at very low electric fields (< 1 V µm(-1)) and repeatable, hysteresis free characteristics. This exploitation of LC alignment effects on CVD graphene films enables a new generation of highly efficient nematic LC scattering displays as well as many other possible applications.

5.
Biochim Biophys Acta ; 1133(3): 301-6, 1992 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-1531302

RESUMO

The effect of estradiol-17 beta on the activities of glycolytic enzymes from female rat brain was studied. The following enzymes were examined: hexokinase (HK, EC 2.7.1.1), phosphofructokinase (PFK, EC 2.7.1.11), aldolase (EC 4.1.2.13), glyceraldehyde-3-phosphate dehydrogenase (EC 1.2.1.12), phosphoglycerate kinase (EC 2.7.2.3), phosphoglycerate mutase (EC 2.7.5.3), enolase (EC 4.2.1.11) and pyruvate kinase (PK, EC 2.7.1.40). The activities of HK (soluble and membrane-bound), PFK and PK were increased after 4 h of hormone treatment, while the others remained constant. The changes in activity were not seen in the presence of actinomycin D. The significant rise of the activities of the key glycolytic enzymes was also observed in the cell culture of mouse neuroblastoma C1300 treated with hormone. Only three of the studied isozymes, namely, HKII, B4 and K4 were found to be estradiol-sensitive for HK, PFK and PK, respectively. The results obtained suggest that rat brain glycolysis regulation by estradiol is carried out in neurons due to definite isozymes induction.


Assuntos
Neoplasias Encefálicas/metabolismo , Encéfalo/metabolismo , Estradiol/farmacologia , Glicólise/efeitos dos fármacos , Neuroblastoma/metabolismo , Animais , Bisfosfoglicerato Mutase/farmacologia , Encéfalo/efeitos dos fármacos , Feminino , Frutose-Bifosfato Aldolase/efeitos dos fármacos , Gliceraldeído-3-Fosfato Desidrogenases/efeitos dos fármacos , Hexoquinase/efeitos dos fármacos , Fosfofrutoquinase-1/efeitos dos fármacos , Fosfoglicerato Quinase/efeitos dos fármacos , Piruvato Quinase/farmacologia , Ratos , Células Tumorais Cultivadas
6.
Biochem Int ; 24(5): 867-75, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1776954

RESUMO

The effect of estradiol-17 beta on the activity of pyruvate kinase from rat brain was investigated at initial stages of hormone administration. After estradiol treatment the rise of pyruvate kinase activity was found in the firmly bound synaptosomal fraction, whereas pyruvate kinase activity in soluble and weakly bound fractions has been reduced. The activation of the enzyme was also discovered after glutaraldehyde fixation on synaptosomal membranes. The possible mechanism of extragenomic estradiol action is discussed.


Assuntos
Encéfalo/enzimologia , Estradiol/farmacologia , Piruvato Quinase/metabolismo , Sinaptossomos/enzimologia , Animais , Ativação Enzimática , Feminino , Glutaral/química , L-Lactato Desidrogenase/metabolismo , Ratos , Fixação de Tecidos
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