Porous crystals are strategic materials with industrial applications within petrochemistry, catalysis, gas storage, and selective separation. Their unique properties are based on the molecular-scale porous character. However, a principal limitation of zeolites and similar oxide-based materials is the relatively small size of the pores, typically in the range of medium-sized molecules, limiting their use in pharmaceutical and fine chemical applications. Metal organic frameworks (MOFs) provided a breakthrough in this respect. New MOFs appear at a high and an increasing pace, but the appearances of new, stable inorganic building bricks are rare. Here we present a new zirconium-based inorganic building brick that allows the synthesis of very high surface area MOFs with unprecedented stability. The high stability is based on the combination of strong Zr-O bonds and the ability of the inner Zr6-cluster to rearrange reversibly upon removal or addition of mu3-OH groups, without any changes in the connecting carboxylates. The weak thermal, chemical, and mechanical stability of most MOFs is probably the most important property that limits their use in large scale industrial applications. The Zr-MOFs presented in this work have the toughness needed for industrial applications; decomposition temperature above 500 degrees C and resistance to most chemicals, and they remain crystalline even after exposure to 10 tons/cm2 of external pressure.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTetrathiafulvalenes, Oligoacenenes, and Their Buckminsterfullerene Derivatives: The Brick and Mortar of Organic ElectronicsMichael Bendikov, Fred Wudl, and Dmitrii F. PerepichkaView Author Information Department of Chemistry and Biochemistry and Exotic Materials Institute, University of California, Los Angeles, California 90095 Centre Énergie, Matériaux et Télécommunications, Institut National de la Recherche Scientifique, 1650 Blvd. Lionel-Boulet, Varennes, Québec J3X 1S2, Canada Cite this: Chem. Rev. 2004, 104, 11, 4891–4946Publication Date (Web):October 26, 2004Publication History Received17 May 2004Published online26 October 2004Published inissue 1 November 2004https://pubs.acs.org/doi/10.1021/cr030666mhttps://doi.org/10.1021/cr030666mresearch-articleACS PublicationsCopyright © 2004 American Chemical SocietyRequest reuse permissionsArticle Views15471Altmetric-Citations1575LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Aromatic compounds,Hydrocarbons,Molecules,Reaction products,Redox reactions Get e-Alerts
We describe a simple and robust method to construct complex three-dimensional (3D) structures by using short synthetic DNA strands that we call "DNA bricks." In one-step annealing reactions, bricks with hundreds of distinct sequences self-assemble into prescribed 3D shapes. Each 32-nucleotide brick is a modular component; it binds to four local neighbors and can be removed or added independently. Each 8-base pair interaction between bricks defines a voxel with dimensions of 2.5 by 2.5 by 2.7 nanometers, and a master brick collection defines a "molecular canvas" with dimensions of 10 by 10 by 10 voxels. By selecting subsets of bricks from this canvas, we constructed a panel of 102 distinct shapes exhibiting sophisticated surface features, as well as intricate interior cavities and tunnels.
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Article Bricks: laying the foundations for graspable user interfaces Share on Authors: George W. Fitzmaurice Dynamic Graphics Project, CSRI, University of Toronto, Toronto, Ontario, Canada M5S 1A4 Dynamic Graphics Project, CSRI, University of Toronto, Toronto, Ontario, Canada M5S 1A4View Profile , Hiroshi Ishii NTT Human Interface Lab, 1-2356 Take, Yokosuka-Shi, Kanagawa, 238-03 Japan NTT Human Interface Lab, 1-2356 Take, Yokosuka-Shi, Kanagawa, 238-03 JapanView Profile , William A. S. Buxton Dynamic Graphics Project, CSRI, University of Toronto, Toronto, Ontario, Canada M5S 1A4 and Alias Research Inc., 110 Richmond Street East, Toronto, Ontario, Canada M5C 1P1 Dynamic Graphics Project, CSRI, University of Toronto, Toronto, Ontario, Canada M5S 1A4 and Alias Research Inc., 110 Richmond Street East, Toronto, Ontario, Canada M5C 1P1View Profile Authors Info & Claims CHI '95: Proceedings of the SIGCHI Conference on Human Factors in Computing SystemsMay 1995 Pages 442–449https://doi.org/10.1145/223904.223964Online:01 May 1995Publication History 528citation5,214DownloadsMetricsTotal Citations528Total Downloads5,214Last 12 Months324Last 6 weeks32 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteGet Access
The uniaxial monotonic compressive stress-strain behavior and other characteristics of unreinforced masonry and its constituents, i.e., solid clay bricks and mortar, have been studied by several laboratory tests. Based on the results and observations of the comprehensive experimental study, nonlinear stress-strain curves have been obtained for bricks, mortar, and masonry and six “control points” have been identified on the stress-strain curves of masonry, which can also be used to define the performance limit states of the masonry material or member. Using linear regression analysis, a simple analytical model has been proposed for obtaining the stress-strain curves for masonry that can be used in the analysis and design procedures. The model requires only the compressive strengths of bricks and mortar as input data, which can be easily obtained experimentally and also are generally available in codes. Simple relationships have been identified for obtaining the modulus of elasticity of bricks, mortar, and masonry from their corresponding compressive strengths. It was observed that for the strong and stiff bricks and mortar of lesser but comparable strength and stiffness, the stress-strain curves of masonry do not necessarily fall in between those of bricks and mortar.
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The paper addresses the problems of evaluation of strength, deformability, and energy dissipation capacity of unreinforced brick masonry walls, within the context of seismic assessment of existing buildings. Possible approaches to simplified strength evaluation are discussed on the basis of experimental and numerical data, and formulae for assessment are presented. The role of the shear ratio in the shear failure mechanisms is put in evidence and shear strength formulae are proposed accordingly. The most significative parameters regarding deformability under cyclic loading are highlighted and energy dissipation due to hysteretic behaviour is quantified for possible use in dynamic models. Experimental results show how ultimate drift seems to be a parameter with high regularity for walls failing in shear. Based on such result, a possible approach for seismic assessment is outlined. © 1997 John Wiley & Sons, Ltd.
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OBJECTIVE: This study determined the prevalence of autism for a defined community, Brick Township, New Jersey, using current diagnostic and epidemiologic methods. METHODS: The target population was children who were 3 to 10 years of age in 1998, who were residents of Brick Township at any point during that year, and who had an autism spectrum disorder. Autism spectrum disorder was defined as autistic disorder, pervasive developmental disorder-not otherwise specified (PDD-NOS), and Asperger disorder. The study used 4 sources for active case finding: special education records, records from local clinicians providing diagnosis or treatment for developmental or behavioral disabilities, lists of children from community parent groups, and families who volunteered for participation in the study in response to media attention. The autism diagnosis was verified (or ruled out) for 71% of the children through clinical assessment. The assessment included medical and developmental history, physical and neurologic evaluation, assessment of intellectual and behavioral functioning, and administration of the Autism Diagnostic Observation Schedule-Generic. RESULTS: The prevalence of all autism spectrum disorders combined was 6.7 cases per 1000 children. The prevalence for children whose condition met full diagnostic criteria for autistic disorder was 4.0 cases per 1000 children, and the prevalence for PDD-NOS and Asperger disorder was 2.7 cases per 1000 children. Characteristics of children with autism in this study were similar to those in previous studies of autism. CONCLUSIONS: The prevalence of autism in Brick Township seems to be higher than that in other studies, particularly studies conducted in the United States, but within the range of a few recent studies in smaller populations that used more thorough case-finding methods.
A specialized tissue type, the keratinizing epithelium, protects terrestrial mammals from water loss and noxious physical, chemical and mechanical insults. This barrier between the body and the environment is constantly maintained by reproduction of inner living epidermal keratinocytes which undergo a process of terminal differentiation and then migrate to the surface as interlocking layers of dead stratum corneum cells. These cells provide the bulwark of mechanical and chemical protection, and together with their intercellular lipid surroundings, confer water-impermeability. Much of this barrier function is provided by the cornified cell envelope (CE), an extremely tough protein/lipid polymer structure formed just below the cytoplasmic membrane and subsequently resides on the exterior of the dead cornified cells. It consists of two parts: a protein envelope and a lipid envelope. The protein envelope is thought to contribute to the biomechanical properties of the CE as a result of cross-linking of specialized CE structural proteins by both disulfide bonds and N(epsilon)-(gamma-glutamyl)lysine isopeptide bonds formed by transglutaminases. Some of the structural proteins involved include involucrin, loricrin, small proline rich proteins, keratin intermediate filaments, elafin, cystatin A, and desmosomal proteins. The lipid envelope is located on the exterior of and covalently attached by ester bonds to the protein envelope and consists of a monomolecular layer of omega-hydroxyceramides. These not only serve of provide a Teflon-like coating to the cell, but also interdigitate with the intercellular lipid lamellae perhaps in a Velcro-like fashion. In fact the CE is a common feature of all stratified squamous epithelia, although its precise composition, structure and barrier function requirements vary widely between epithelia. Recent work has shown that a number of diseases which display defective epidermal barrier function, generically known as ichthyoses, are the result of genetic defects of the synthesis of either CE proteins, the transglutaminase 1 cross-linking enzyme, or defective metabolism of skin lipids.
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The Internet has increased the flexibility of retailers, allowing them to operate an online arm in addition to their physical stores. The online channel offers potential benefits in selling to customer segments that value the convenience of online shopping, but it also raises new challenges. These include the higher likelihood of costly product returns when customers' ability to “touch and feel” products is important in determining fit. We study competing retailers that can operate dual channels (“bricks and clicks”) and examine how pricing strategies and physical store assistance levels change as a result of the additional Internet outlet. A central result we obtain is that when differentiation among competing retailers is not too high, having an online channel can actually increase investment in store assistance levels (e.g., greater shelf display, more-qualified sales staff, floor samples) and decrease profits. Consequently, when the decision to open an Internet channel is endogenized, there can exist an asymmetric equilibrium where only one retailer elects to operate an online arm but earns lower profits than its bricks-only rival. We also characterize equilibria where firms open an online channel, even though consumers only use it for research and learning purposes but buy in stores. A number of extensions are discussed, including retail settings where firms carry multiple product categories, shipping and handling costs, and the role of store assistance in impacting consumer perceived benefits.
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ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInterpenetrating Molecular Ladders and BricksMakoto Fujita, Yoon Jung Kwon, Osamu Sasaki, Kentaro Yamaguchi, and Katsuyuki OguraCite this: J. Am. Chem. Soc. 1995, 117, 27, 7287–7288Publication Date (Print):July 1, 1995Publication History Published online1 May 2002Published inissue 1 July 1995https://doi.org/10.1021/ja00132a046RIGHTS & PERMISSIONSArticle Views1023Altmetric-Citations389LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (271 KB) Get e-AlertsSupporting Info (3)»Supporting Information Supporting Information Get e-Alerts