8,272 research outputs found
Enhancement of surface properties of cementitious materials by phosphate treatments
This study aims at investigating the ability of aqueous phosphate solutions to improve the surface properties of cement pastes via the formation of low-solubility calcium phosphate (CaP) phases. Diammonium hydrogen phosphate (DAP), dipotassium hydrogen phosphate (DPP) and disodium hydrogen phosphate (DSP) were investigated based on thermodynamic modeling and experiments. For DPP, the influence of concentration and cement age was evaluated. A 1 M DPP + 1mM CaCl2 solution applied to cement hydrated for 7 days was most promising. The CaP coating formed after 24 hours of exposure resulted in significant improvements in the cement pastes’ resistance to abrasion, surface indentation and staining. Preliminary durability tests by immersion in water were successfully carried out to ascertain that no efflorescence due to soluble salts appeared and that mechanical improvement was retained. Compared to DAP, DPP has the advantage of not releasing NH3 into the atmosphere, thus preventing unpleasant odor and improving the treatment’s environmental sustainability
Dataset: Stability of hemicarbonate under cement paste-like conditions
Data, and scripts (analysis, plots) to go with the publication:
Stability of hemicarbonate under cement paste-like conditions
Fabien Georget (a,1,∗), Barbara Lothenbach (b) , William Wilson (a,c) , Franco Zunino (a) Karen L. Scrivener (a)
a: aboratory of Construction Materials, LMC, EPFL-STI-IMX, Station 12, CH-1015
Lausanne, Switzerland
b: Empa, Concrete & Asphalt Laboratory, Dübendorf, Switzerland
c: Sherbrooke University, Sherbrooke, Quebec, Canada
1: current address: Institute of Building Materials Research, RWTH Aachen, Aachen, Germany
* corresponding author
To be submitted to Cement and Concrete Researc
Barbara James
Date:1943Barbara was born in Holdredge, Nebraska in the United States of America in 1943. In 1960 she arrived in Darwin working in a variety of occupations such as a journalist, historian, author, activist, advocate and editor. Barbara wrote 13 books including "No Man's Land" which explored the contributions of women in the Northern Territory. She also received a number of awards including 2001 NT Heritage Award, the 2000 NT Literary Essay Awards and the Chief Minister's Women's Achievement Award in 1999.JournalistHistorianAuthorActivistEditorAmerica
Synthesis and properties of a belite-CSA cement obtained using only waste materials
Belite-calcium sulfoaluminate (BCSA) clinkers are usually obtained at temperatures lower than 1350°C by burning a raw meal composed of limestone, clay, natural gypsum and bauxite. The use of limestone quarry waste, dredged sediments, water potabilization sludge and flue gas desulfurization gypsum as complete substitutes for natural raw materials was investigated. Two BCSA clinkers based on natural raw materials and on waste materials, respectively, were synthesized in a laboratory electric furnace. Two BCSA cements were prepared by blending the clinkers with natural anhydrite at the same calcium sulfate / ye'elimite ratio, and their hydration behaviour was investigated.
The BCSA cement made from the waste materials showed a faster early reaction than the one prepared from natural raw materials. At later ages, both cements developed a similar hydrate assemblage, consisting mainly of ettringite, AFm-phases and strätlingite. Also the physical properties, i.e. compressive strength, porosity and volume stability, are rather similar, with the exception that late compressive strength (after 56 days) is significantly higher for the cement made from waste materials. The results show that it is possible to manufacture BCSA clinkers entirely from local waste materials
Barbara Ras - Sowell Conference 2017
Barbara Ras, San Antonio, Poet, author of "Bite Every Sorrow" and "The Last Skin
Exclusive interview with author Barbara Kingsolver
Exclusive interview with author Barbara Kingsolver for her 2018 novel *Unsheltered
Dataset for publication: Post‐war architecture and urban planning as means of reinventing Opole’s past and identity
The collection includes files related to the publication: Barbara Szczepańska, Post‐War Architecture and Urban Planning as Means of Reinventing Opole’s Past and Identity, „Urban Planning”, Vol 8, No 1 (2023): Bombed Cities: Legacies of Post-War Planning on the Contemporary Urban and Social Fabric, pp. 266-278, https://doi.org/10.17645/up.v8i1.6079. The collection includes figures used in the publication:Opole_plan A plan of Opole, with areas of Ostrówek (left), Market Square (center) and Central Square (right) highlighted in red. Originally published in: "Guidebook to the city of Opole" ("Przewodnik po mieście Opolu", Opole: Księgarnia Opolska, 1948, https://polona.pl/preview/2f383a4a-5e9e-444d-9e94-366b8ac8610d). Author: Z. Streer. Licence: CC0Opole_Monument to the Opole Silesian Fighters for Freedom A photograph depicting Monument to the Opole Silesian Fighters for Freedom (Pomnik Bojownikom o Wolność Śląska Opolskiego) in Opole. Author: Barbara Szczepańska. Licence: CC0Opole_monument of Kazimierz I Opolczyk A photograph depicting the monument of Kazimierz I Opolczyk in the Market Square in Opole. Author: Barbara Szczepańska. Licence: CC0Opole_Market Square_eastern frontage A photograph depicting eastern frontage of the Market Square in Opole. Author: Barbara Szczepańska. Licence: CC0Opole_Market Square_eastern frontage_before 1945 A photograph depicting eastern frontage of the Market Square in Opole before 1945. Originally published on Wikimedia Commons: https://commons.wikimedia.org/wiki/File:Market_Square_in_Opole,_eastern_frontage.jpg. Author: unknown. Licence: CC0Opole_monument of Frederick the Great A photograph depicting monument of Frederick the Great in Opole, before 1945. Originally published on Wikimedia Commons: https://commons.wikimedia.org/wiki/File:Opole_Oppeln_Denkmal_Friedrich_der_Große.jpg. Author: unknown. Licence: CC0</ul
'A date with Barbara': paracosms of the self in biographies of Barbara Newhall Follett
In 1927, 13-year-old Barbara Newhall Follett published her first book, the critically acclaimed novel, The House Without Windows and Eepersip's Life There.
Twelve years later, on December 7, 1939, 25-year-old Barbara quarrelled with her husband and left her apartment in Boston with $30 in her pocket, and a notebook. She was never seen again.
The House Without Windows is set in a paracosm (Farksolia) she invented, and ends with the metamorphosis of the titular character into a 'fairy-a wood nymph … invisible for ever to all mortals, save those few who have minds to believe, eyes to see'.
In Barbara's (auto)biography, The Unconscious Autobiography of a Child Genius (1966), written by Harold Grier McCurdy 'in collaboration with Helen Follett' (Barbara's mother), the authors wonder: 'Can we be far wrong in substituting Barbara's name for Eepersip's in the closing scenes of [House Without Windows]?
In this paper, I grapple with the formal and ethical challenges of writing about Barbara Newhall Follett, and the ways her family and others have approached the problem of writing her unresolved life story: a child raised and educated in solitude, a celebrated 'natural' child author, a young woman whose disappearance remains unsolved. The paper will explore the ways in which adults write the stories of children's lives, as nostalgia and fable, as fairytale and paracosmic narrative, and the ways in which Barbara's biographers have, consciously and unconsciously, created biographical concordances, or paracosms of the self, in seeking to make meaning of her life's story
Barbara Ehrenreich: Blood Rites: A New Evolutionary Perspective on Violence
Barbara Ehrenreich, author, social critic and political essayist, discusses the emotional and social aspects of warfare and violence.
Barbara Ehrenreich is an American author and political activist who describes herself as a myth buster by trade” and has been called a veteran muckraker by The New Yorker.During the 1980s and early 1990s she was a prominent figure in the Democratic Socialists of America. She is a widely read and award-winning columnist and essayist, and author of 21 books. Ehrenreich is perhaps best known for her 2001 book Nickel and Dimed: On (Not) Getting By in America
Barbara Dicker Oration 2018 - The phenomenon of hallucinations
The 2018 Barbara Dicker Oration was presented by Professor Iris Sommer on 13 September 2018. Professor Sommer is a best-selling author and Professor of Cognitive Aspects of Neurological and Psychiatric Disorder at the Department of Neuroscience at the University Medical Center Groningen, Netherlands. Entitled The phenomenon of hallucinations, Professor Sommer offered a holistic view into the research and experiences of hallucinations. It’s actually more common than you might think but what happens in our brains when we hallucinate? And what does this mean for new treatments and interventions
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