Pramod Kumar Singh

I materiali che presentano pi di una propriet ferromagnetica primaria, ossia ferromagnetismo, ferroelettricit e ferroelasticit , sono noti come materiali multiferroici. Questi materiali offrono la possibilit di potenziali applicazioni in dispositivi di stoccaggio, sensori, dispositivi spintronici e reazioni fotocatalitiche. Il BiFeO3 l'unico materiale multiferroico che ha una temperatura di Neel antiferromagnetica di tipo G 653K e una temperatura di Curie ferroelettrica 1100K, entrambe superiori alla temperatura ambiente. Il BiFeO3 contiene propriet multiferroiche a temperatura ambiente, ma mostra anche una grande dispersione di corrente dovuta a difetti, vacancy di ossigeno e basse propriet ferroelettriche che ne limitano le propriet . Per ridurre queste limitazioni, possibile drogare il materiale di transizione al posto del ferro. Questo libro rappresenta la sintesi e gli studi strutturali, ottici e fotocatalitici della ferrite di bismuto (BiFeO3) e delle nanoparticelle di ferrite di bismuto drogate con nichel (BiFe1-xNixO3).

Os materiais que apresentam mais do que uma propriedade f rrica prim ria, ou seja, ferromagnetismo, ferroeletricidade e ferroelasticidade, s o conhecidos como materiais multiferr icos. Estes materiais oferecem possibilidades de aplica es potenciais em dispositivos de armazenamento, sensores, dispositivos spintr nicos e reac es fotocatal ticas. O BiFeO3 o nico material multiferr ico que tem uma temperatura de Neel antiferromagn tica do tipo G 653K e uma temperatura de Curie ferroel ctrica 1100K, ambas acima da temperatura ambiente. O BiFeO3 cont m propriedades multiferr icas temperatura ambiente, mas tamb m apresenta grandes fugas de corrente devido a defeitos, vac ncia de oxig nio e baixas propriedades ferroel ctricas, o que limita as suas propriedades. Para diminuir estas limita es, pode ser efectuada a dopagem de material de transi o em vez de ferro. Este livro apresenta a s ntese, bem como os estudos estruturais, pticos e fotocatal ticos de nanopart culas de ferrite de bismuto (BiFeO3) e de ferrite de bismuto dopada com n quel (BiFe1-xNixO3).

Die Materialien, die mehr als eine prim re ferroische Eigenschaft aufweisen, d. h. Ferromagnetismus, Ferroelektrizit t und Ferroelastizit t, werden als multiferroische Materialien bezeichnet. Diese Materialien bieten M glichkeiten f r potenzielle Anwendungen in Speicherger ten, Sensoren, spintronischen Ger ten und photokatalytischen Reaktionen. BiFeO3 ist das einzige multiferroische Material, das eine antiferromagnetische Neel-Temperatur vom G-Typ ( 653 K) und eine ferroelektrische Curie-Temperatur ( 1100 K) hat, die beide ber der Raumtemperatur liegen. BiFeO3 weist bei Raumtemperatur multiferroische Eigenschaften auf, zeigt aber aufgrund von Defekten und Sauerstoffleerstellen einen hohen Leckstrom und geringe ferroelektrische Eigenschaften, was seine Eigenschaften einschr nkt. Um diese Einschr nkungen zu verringern, kann anstelle von Eisen eine Dotierung mit einem bergangsmaterial vorgenommen werden. In diesem Buch werden die Synthese sowie die strukturellen, optischen und photokatalytischen Studien von Bismut-Ferrit (BiFeO3) und Nickel-dotierten Bismut-Ferrit (BiFe1-xNixO3) Nanopartikeln dargestellt.

The development and the interaction of the science and the technology have created the fast growth of the human knowledge. The knowledge and the information has becoming the key point of the social development, which makes the knowledge innovation become the hot spot of the global attention. But the library management is the important means of the knowledge dissemination and the knowledge innovation, which arouses the people's attention in the world. This book elaborates on how technological innovations have led to the improved information management and library services. This book highlights and study that the combination of these effects is likely to have a positive impact not only from an economic point of view but more broadly from a social point of view.

In this book, changes in the collection of funds and attendance of libraries under the influence of the growing popularity of electronic resources in comparison with paper libraries are considered. Methods of increasing the efficiency of using licensed databases, improving electronic catalogs and websites of libraries are discussed. A brief review of metadata formats describing electronic resources and collections, logical structures of electronic publications, as well as standards for data collection and exchange was made. A range of new responsibilities for librarians responsible for electronic resources is described. Changes in the field of library education are considered. Problems of preservation of electronic resources, their influence on schoolchildren, students and in general on libraries are discussed.Over the last ten to fifteen years, a new generation of readers has grown up in Western and northeastern European countries (especially in the US and Russia), who prefer electronic editions to paper. Accordingly, libraries increasingly redistribute funds in favor of electronic publications to the detriment of paper publications. The American Association of Scientific Libraries, having conducted a study among more than 100 of its members, found that over the last decade, the annual average library spending on electronic resources increased by 400% to approximately $ 1.5 million in 2002. At the same time, the total budget for the acquisition of library funds in the same period grew by only 61%. Libraries, as a rule, primarily cancel paper subscriptions to publications in the field of humanities and social and political sciences, and subscriptions to scientific and technical publications are canceled to a lesser extent. The advantages of using electronic publications are well known to librarians, and they are actively replenishing their collections. A large university library today can offer students, faculty and researchers up to 25,000 electronic periodicals in licensed databases and up to 200,000 e-books and more.In addition to paid electronic resources, the easy-to-use Internet search engines (Google, for example) and websites provide serious competition to traditional library collections. Recognizing the fact that more and more readers use the Internet to access information, libraries themselves have actively engaged in the creation of electronic collections by digitizing their own funds and building electronic libraries. Collections of materials for digitization, digitization technologies and methods of building electronic libraries contribute to the birth of new information resources. It significantly increases the effectiveness of education and research allows creating unique collections of previously disparate documents. However, it can also be found in different libraries and archives, including foreign ones can detect unknown collections by combining electronic descriptions of materials on a specific subject from different storages that simply did not know about the existence of the respective collections from each other.The growing popularity of electronic resources and the use of the Internet as an information source has led to a decrease in library attendance and a reduction in the number of references and bibliographic services. For example, at the University of Idaho, the number of library visitors has decreased by more than 20% since 1997, while the use of articles in electronic form has grown by 350% since 1999. In these conditions, public and university libraries try to at¬tract readers back to their premises, creating comfortable conditions for reading and working with computers, allocating rooms for recreation and meetings, and provide on-site cafeterias. Competing with free search engines and sites on the Internet, many of which contain information of questionable quality, libraries have improved their own electronic catalogs and websites, and provide readers with access to better-paid electronic resources. The same licensed databases al¬low readers to use remotely the Internet using the personal passwords and proxy server of the library.

The library is one of the oldest cultural institutions. Over the long period of human history, its social functions have undergone significant changes. The purpose of the first libraries was the storage of documents. Since its inception until today, the library has passed the first stage of the evolution of the public mission: from serving the needs of the ruling elite to meeting public needs. The library has become a social institution, which includes information and cultural components and ensures the stability of ties and relations within the society. There is an evolution of the social role of the library; their functions are developing and becoming more diverse. Along with information, cultural, educational and educational activities, they are increasingly playing a role in the democratization of library work and society, in the formation of social harmony and stability, in socialization, in the development of people’s intellectual potential.The nature of the interaction of libraries with various institutions, with authorities, with users is changing. It is also natural that in comparison with other cultural institutions in the developed world it is in libraries that reforms are reflected most strongly and dramatically, qualitatively changing their role in society, expanding their demands. Libraries are mostly dependent on changes in their environment-the state of book publishing, book distribution, the development of the information sphere and telecommunications, the work of mail and transport, and customs. Most importantly, changes in the structure of society, a decline in the living standards of a large part of it, the emergence of new spheres employment and new social groups with information needs.This book presents research studies about different libraries, library systems and information on library science, benefits and role of libraries, and the importance of libraries. This book traces the transformation of social functions of scientific libraries in the conditions of the informatization of society, in particular, the development of the cultural and information function as an important component of the socio-cultural function. The activity of library institutions should be subordinated to the optimal cultural and information support of life and society, and every reader. Transformation of the social functions of scientific libraries, under the circumstances of the informatization of society and the development of the cultural and informational function is an important component of socio-cultural function. The activity of library institutions must be in context to the optimal cultural and informational support for vital activity of a society and its separate members as well.