8,447 research outputs found
New trends in crystal engineering.
No full textThe articles and highlights presented at the second CrstEngComm meeting, held in Nottingham in Sept. 2004 are reviewed. The discussion has highlighted the current development of crystal engineering and allowed to emerge some of its future potentials. In particular. the papers described in this highlight focus on four fundamental aspects: (i) intermol. interactions: evaluation and application to crystal design; (ii) networks: design and applications: (iii) approaches to crystal synthesis; (iv) polymorphism, solvates and chiral crystal resol
Synthesis and structural characterisation of coordination polymers designed using discrete phosphonodithioato NiII complexes and dipyridyl donor ligands
No full textSquare-planar phosphonodithioato complexes [Ni(ROdtp)2] [ROdtp = (4-MeOPh)(RO)PS22; R = Me (1), Et (2)] have been treated with four different dipyridyl donors, namely 1-pyridyl-4-(4’-pyridyl-ethynyl)-benzene (I), 4,4’-bipyridine (II), 3,6-bis(4-pyridyl)-1,2,4,5-tetrazine (III), and 3,6-bis(3-pyridyl)-1,2,4,5-tetrazine (IV). The single crystal X-ray structures of the reaction products (1.I) (3), (1.III) (5), and (2.IV) (6), along with that of the previously reported compound (2.II) (4) prove the ability of dipyridyl donors to self-assemble with coordinatively unsaturated nickel-phosphonodithioates to give 1D coordination polymers whose topology, such as the shape and the separation between consecutive metal centres, can be tuned through structural modifications in the N-donor linkers. DFT calculations on the free ligands have been performed with the goal of elucidating the nature of the frontier orbitals of the ligands involved in the coordination of the nickel complexes
Designed assembly of low-dimensional molecular units: Novel neutral coordination polymers based on (phosphonodithioato)NiII complexes
No full textThe reactions of phosphonodithioato complexes [Ni(ROdtp)2] [where ROdtp = (4-MeOPh)(RO)PS2; R = Et, Me] with 4,4′-bipy and N,N′-bis-(3-pyridinylmethylene)benzene-1,4-diamine (bdpy), respectively, yield the 1:1 coordination polymers [Ni(EtOdtp)2(bipy)]8 and [Ni(MeOdtp)2(bdpy)]∞, whose syntheses and single-crystal X-ray diffraction analyses are reported
The expedition of the Sultan in 1538 in Moldavia : (in the view of an Italian author)
Full text linkThe expedition of the Sultan in 1538 in Moldavia : (in the view of an Italian author). - In: Colloquia, an 2006, vol. 13, nr. 1-2, p. 257-271
5G NR : the next generation wireless access technology /
No full text5G NR: The Next Generation Wireless Access TechnologyïŽfollows the authors' highly celebrated books on 3G and 4G by providing a new level of insight into 5G NR. After an initial discussion of the background to 5G, including requirements, spectrum aspects and the standardization timeline, all technology features of the first phase of NR are described in detail. Included is a detailed description of the NR physical-layer structure and higher-layer protocols, RF and spectrum aspects and co-existence and interworking with LTE. The book provides a good understanding of NR and the different NR technology components, giving insight into why a certain solution was selected. Content includes: Key radio-related requirements of NR, design principles, technical featuresDetails of basic NR transmission structure, showing where it has been inherited from LTE and where it deviates from it, and the reasons whyNR Multi-antenna transmission functionalityDetailed description of the signals and functionality of the initial NR access, including signals for synchronization and system information, random access and pagingLTE/NR co-existence in the same spectrum, the benefits of their interworking as one systemThe different aspects of mobility in NR RF requirements for NR will be described both for BS and UE, both for the legacy bands and for the new mm-wave bands.Includes bibliographical references and index.Vendor-supplied metadata.5G NR: The Next Generation Wireless Access TechnologyïŽfollows the authors' highly celebrated books on 3G and 4G by providing a new level of insight into 5G NR. After an initial discussion of the background to 5G, including requirements, spectrum aspects and the standardization timeline, all technology features of the first phase of NR are described in detail. Included is a detailed description of the NR physical-layer structure and higher-layer protocols, RF and spectrum aspects and co-existence and interworking with LTE. The book provides a good understanding of NR and the different NR technology components, giving insight into why a certain solution was selected. Content includes: Key radio-related requirements of NR, design principles, technical featuresDetails of basic NR transmission structure, showing where it has been inherited from LTE and where it deviates from it, and the reasons whyNR Multi-antenna transmission functionalityDetailed description of the signals and functionality of the initial NR access, including signals for synchronization and system information, random access and pagingLTE/NR co-existence in the same spectrum, the benefits of their interworking as one systemThe different aspects of mobility in NR RF requirements for NR will be described both for BS and UE, both for the legacy bands and for the new mm-wave bands.Elsevie
Coordination Polymers: From Metal–Organic Frameworks to Spheres
No full textSphere of destiny: Metal–organic spheres with remarkable encapsulation properties are readily prepared and their ability to host a wide range of guest species, including nanoparticles, fluorescent dyes, and quantum dots, is demonstrated. Both the metal–organic spheres and the encapsulated species maintain their fluorescent or magnetic properties, highlighting the importance of these systems as new multifunctional materials.<br/
Nanostructured frameworks for materials applications
No full textStrategies for the synthesis of frameworks materials based upon either coordination bonds or hydrogen-bonding interactions are described. The utilization of coordinate bonds for the construction of coordination frameworks is presented describing not only strategies for controlling framework structure but also illustrating how such networks can be used for applications in the storage of guest species, such as H2. The exploitation of hydrogen-bonding for generating self-assembled surface arrays is also described, again illustrating controlled molecular entrapment for nanostructure fabrication.</p
Inleidende studie betreffende de mogelijkheden tot verhoging van de Emmapolderdijk
No full textDe onderhavige nota is ontstaan als uitvloeisel van voorstellen van de afdelingsingenieur voor de afdeling Landaanwinningswerken aan de Hoofdingenieur-Direkteur in de direktie Groningen betreffende het opzetten van een proef met golfremmende elementen op de Emmapolderdijk, van de daarop gevolgde gedachtenwisseling, en van de brief nr. 4048 van 3 juli 1963 van de genoemde Hoofdingenieur-Direkteur, waarin aan de afdeling Landaanwinningswerken werd opgedragen voorstudieste verrichten omtrent de mogelijkheden tot verhoging van de Emmapolderdijk
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