Results 51 to 60 of about 2,881 (187)

Investigate and Comparison Effect add Amorphous and Crystalline - Nano SiO2 on Properties of Concrete [PDF]

Engineering and Technology Journal, 2015
In this paper, the study included the comparison between amorphous silica and crystalline silica (quartz), and with nano scale size, two types of silicawere added to concrete by ratios (5%, 10%, 15%, and 20%) as a replacement by the weight of cement ...
Rami Joseph Aghajan Sldozian
doaj   +1 more source

Universities as the Next Counterintelligence Battleground in Geopolitical Contests

Global Policy, EarlyView.
ABSTRACT Globally, universities are increasingly becoming the target of foreign national security actors, engaging in espionage, sabotage, foreign interference and intellectual property theft. Despite that, there has been no examination of the utilisation of counterintelligence approaches by universities to the threats they face from the subordination ...
Brendan Walker‐Munro, Sascha‐Dominik Dov Bachmann   +1 more
wiley   +1 more source

Application of schmidt hammer and ultrasonic pulse velocity for structural integrity assessment in water dams

Journal of Infrastructure Preservation and Resilience
This study investigates the integration of Schmidt Hammer Rebound Numbers and Ultrasonic Pulse Velocity (UPV) measurements to estimate the compressive strength of reinforced concrete in water dam structures.
Wilson M. Kairu, Siphila W. Mumenya, Kenneth D. Njoroge, Ian M. Kaniu   +3 more
doaj   +1 more source

Junctional sensitivity and atrophy progression rate of geographic atrophy secondary to age‐related macular degeneration

Acta Ophthalmologica, EarlyView.
Abstract Purpose To determine the relationship between the baseline junctional retinal sensitivity measured with microperimetry and the atrophy progression rate in eyes with geographic atrophy (GA) secondary to age‐related macular degeneration. Methods In this prospective cohort study, patients with GA were examined with fundus autofluorescence (FAF ...
Alexander Kai Thomsen, Jenni Martinez Villarruel Hinnerskov, Miranda Maung, Aubin Mutschler, SriniVas Sadda, Torben Lykke Sørensen   +5 more
wiley   +1 more source

Out in the cold? A review of Early Middle Palaeolithic settlements in northern Central Europe, age data and geological preconditions for site formation and preservation

Boreas, EarlyView.
The characteristics of settlement of Neanderthals in northern Central Europe during the earlier phases of the Middle Palaeolithic (Marine Isotope Stage 8–6) have been a matter of debate for decades, specifically regarding the population dynamics at such latitudes during the coldest phases. In this paper, we review the known archaeological record of the
Gianpiero Di Maida, Jutta Winsemann, Malte Hoffmann, Tobias Lauer, Utz Böhner, Thomas Terberger   +5 more
wiley   +1 more source

Refining the timing of Middle Pleistocene (MIS 12 to MIS 6) ice advances into northern central Europe: sedimentological analysis and single‐grain luminescence dating of glaciotectonic complexes and tunnel‐valley fills

Boreas, EarlyView.
We summarize the current state of knowledge on the age of the Middle Pleistocene ice advances into northern central Europe and provide 25 new single‐grain feldspar luminescence ages of Elsterian and Saalian glacigenic sediments to constrain the age of the ice advances and their tentative correlation with marine isotope stages/substages.
Niklas von Soest, Neda Rahimzadeh, Debra Colarossi, Falko Malis, Tobias Lauer, Wera Sander‐Beuermann, Yvonne Spychala, Christian Brandes, Runa Fälber, Sumiko Tsukamoto, Jutta Winsemann   +10 more
wiley   +1 more source

Bio-deterioration of stone and concrete by Melanopsis praemorsa in Gan-HaShlosha national park—A case study

Case Studies in Construction Materials, 2020
Gan HaShlosha national park contain two ponds of running brackish water. Dams were built on the ponds in the 80 s. Some masonary from the dams, as well as other underwater structure, have deteriorated.
Amit Kenny
doaj   +1 more source

Schmidt Hammer Rebound' users guide: IBM-PC/AT computer calculation of uniaxial compressive strength using the Schmidt Hammer

, 1986
Le présent rapport décrit le programme "Rebond du marteau de Schmidt" (Schmidt Hammer Rebound) qui permet de calculer la résistance à la compression uniaxiale de la roche à l'aide de nombres-indices du rebond du marteau de Schmidt. Ce programme est écrit en langage BASIC A Version 3,10 pour un ordinateur IBM-PC/AT.
M Issard, T R C Aston
openaire   +1 more source

Single‐grain K‐feldspar luminescence dating on primary and re‐deposited aeolian sediments in Mongolia

Boreas, EarlyView.
Owing to its location in the semi‐arid region of northern Central Asia, Mongolia is highly sensitive to climate change and therefore provides an excellent setting for palaeoenvironmental research. Proxy data from different sediment types are crucial for interpreting past climate changes and landscape evolution, while burial ages provide chronological ...
Junjie Zhang, Michael Klinge, Sumiko Tsukamoto, Daniela Sauer, Manfred Frechen   +4 more
wiley   +1 more source

The Laser Scanner Technique: A Tool for Determining Shear Strength Parameters of Rock Mass Discontinuities

Applied Sciences
When evaluating the shear strength of rock mass discontinuities, certain challenges arise due to the difficulty in quantifying the roughness characteristics of surfaces and the strength of asperities.
Margherita Zimbardo, Alessandra Nocilla, Anna Scotto di Santolo   +2 more
doaj   +1 more source