Chemomagnetism, magnetoconcentration effect and "fishtail" anomaly in chemically-induced granular superconductors

Within a 2D model of Josephson junction arrays (created by 2D network of twin boundary dislocations with strain fields acting as insulating barrier between hole-rich domains in underdoped crystals), a few novel effects expected to occur in intrinsically granular material are predicted including: (i) Josephson chemomagnetism (chemically induced magnetic moment in zero applied magnetic field) and its influence on a low-field magnetization (chemically induced paramagnetic Meissner effect), and (ii) magnetoconcentration effect (creation of oxygen vacancies in applied magnetic field) and its influence on a high-field magnetization (chemically induced analog of "fishtail" anomaly). The conditions under which these effects can be experimentally measured in non-stoichiometric high-T_c superconductors are discussed.Comment: 5 LaTeX pages (jetpl.sty included), 3 EPS figures. To be published in JETP Letters (January 2003

The role of green zones in the spatial shaping of the urban structure of Yerevan

Изменение социально-экономических условий РА резко сказалось на процессе градостроительной реорганизации столицы - прервалась единая система озеленения города, а также миними-зировалась роль отдельных зеленых общественных массивов в деле организации городского пространства. В статье поднят вопрос о роли зеленых пространств в пространственном формо-образовании городской структуры, и, в частности Еревана на современном этапе, а также некоторые видения в деле решения затрагиваемых проблем.The change of the socio-economic conditions of the Republic of Armenia had a sharp impact on the process of town-planning reorganization of the capital - the uniform system of landscaping of the city was interrupted, as well as the role of separate green public massifs in the organization of urban space was minimized. The article raises the question on the role of green spaces in the spatial shaping of the city structure, and in particular, that of Yerevan at present stage, as well as some views in solving related issues