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Testing non-destructive spectrometric methods for the identification and distinction of archaeological pine wood tar and birch bark tar

Despotopoulou, M. (author), Langejans, G.H.J. (author), Hendrikx, R.W.A. (author), Joosten, Ineke (author), Nijemeisland, M. (author), Poulis, J.A. (author), Kozowyk, P.R.B. (author)

Archaeological findings prove the appearance and use of birch bark tar since the Middle Palaeolithic. The production and use of birch bark tar and pine wood tar has overlapped since at least the late Neolithic, but probably for much longer. The reliable chemical identification of such archaeological tar residues can offer valuable insights...

journal article 2024

document

A multi-analytical approach reveals flexible compound adhesive technology at Steenbokfontein Cave, Western Cape

Aleo, A. (author), Jerardino, Antonieta (author), Chasan, R. (author), Despotopoulou, M. (author), Ngan-Tillard, D.J.M. (author), Hendrikx, R.W.A. (author), Langejans, G.H.J. (author)

Evidence of different compound resin-based adhesives is present in South Africa from at least 77000 years ago. Ancient glue production is considered one of the oldest known highly complex technologies, requiring advanced technological and mental abilities. However, our current knowledge of adhesive materials, recipes, and uses in South Africa is...

journal article 2024

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Revisiting the Electrochemical Nitrogen Reduction on Molybdenum and Iron Carbides: Promising Catalysts or False Positives?

Izelaar, B. (author), Ripepi, D. (author), Asperti, S. (author), Dugulan, A.I. (author), Hendrikx, R.W.A. (author), Bottger, A.J. (author), Mulder, F.M. (author), Kortlever, R. (author)

The electrochemical dinitrogen reduction reaction (NRR) has recently gained much interest as it can potentially produce ammonia from renewable intermittent electricity and replace the Haber-Bosch process. Previous literature studies report Fe- and Mo-carbides as promising electrocatalysts for the NRR with activities higher than other metals....

journal article 2023

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Benchmarking the Electrochemical CO₂ Reduction on Polycrystalline Copper Foils: The Importance of Microstructure Versus Applied Potential

Asperti, S. (author), Hendrikx, R.W.A. (author), Gonzalez Garcia, Y. (author), Kortlever, R. (author)

Copper is one of the most promising catalysts for the CO₂ reduction reaction (CO₂RR) due to its unique capability of producing multicarbon products in appreciable quantities. Most of the CO₂RR research efforts have been directed towards the development of new electrocatalysts to either increase product...

journal article 2022

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Dislocations, texture and stress development in hydrogen-cycled Pd thin films: An in-situ X-ray diffraction study

Verma, N. (author), Delhez, R. (author), van der Pers, N.M. (author), Hendrikx, R.W.A. (author), Huizenga, R.M. (author), Bottger, A.J. (author)

For Pd thin films, microstructural changes involved during hydrogen cycling provide the information needed to predict and optimize the film's mechanical strength. In this paper, a systematic study of the morphology, microstructure, texture, and stress has been performed on Pd thin films during hydrogen loading and deloading cycles at room...

journal article 2022

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Efficient formation of vivianite without anaerobic digester: Study in excess activated sludge

Prot, T.J.F. (author), Pannekoek, W. (author), Belloni, C. (author), Dugulan, A.I. (author), Hendrikx, R.W.A. (author), Korving, L. (author), van Loosdrecht, Mark C.M. (author)

It was recently discovered that vivianite (Fe₃(PO₄)₂.8H₂O) could be magnetically extracted from digested activated sludge which opened a new route for phosphorus recovery (Wijdeveld et al. 2022). While its formation in digested sludge is regularly reported, it is not yet studied for fresh,...

journal article 2022

document

A simple and effective attachment to prevent dome diffraction reaching 2D or 1D detectors in x-ray diffractometers

van der Pers, N.M. (author), Hendrikx, R.W.A. (author), Bottger, A.J. (author)

An attachment has been developed for x-ray diffractometer systems equipped with a domed stage when using a 2D or 1D detector. It consists of a single screen in front of the detector positioned such that it blocks diffraction from the dome. This results in measured data free of disturbing spurious peaks and background, thereby greatly...

journal article 2021

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Iron can be microbially extracted from Lunar and Martian regolith simulants and 3D printed into tough structural materials

Castelein, Sofie M. (author), Aarts, Tom F. (author), Schleppi, Juergen (author), Hendrikx, R.W.A. (author), Bottger, A.J. (author), Benz, D. (author), Brouns, S.J.J. (author), Meyer, A.S. (author), Lehner, B. (author)

In-situ resource utilization (ISRU) is increasingly acknowledged as an essential requirement for the construction of sustainable extra-terrestrial colonies. Even with decreasing launch costs, the ultimate goal of establishing colonies must be the usage of resources found at the destination of interest. Typical approaches towards ISRU are...

journal article 2021

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Single-crystal copper films on sapphire

Janssen, G.C.A.M. (author), van der Pers, N.M. (author), Hendrikx, R.W.A. (author), Bottger, A.J. (author), Kwakernaak, C. (author), Rieger, B. (author), Sluiter, M.H.F. (author)

Single-crystal copper films on sapphire have recently been reported upon in relation to graphene growth on these films. In the present paper the kinetics of the formation of single crystal copper films is investigated. We demonstrate the importance of heating the sapphire substrate in 1000 hPa oxygen, followed by a fast cooling prior to...

journal article 2020

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Microstructure characterisation and mechanical properties of ODS Eurofer steel subject to designed heat treatments

Fu, J. (author), Brouwer, J.C. (author), Hendrikx, R.W.A. (author), Richardson, I.M. (author), Hermans, M.J.M. (author)

The present work deals with oxide dispersion strengthened (ODS) Eurofer steel fabricated by powder metallurgy involving mechanical alloying and spark plasma sintering. A heat treatment route including normalising and tempering was applied to the as-produced steel, based on differential scanning calorimetry (DSC) measurement. The...

journal article 2020

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Radioactive holmium phosphate microspheres for cancer treatment

Gil Arranja, A. (author), Hennink, W. E. (author), Denkova, A.G. (author), Hendrikx, R.W.A. (author), Nijsen, J. F.W. (author)

The aim of this study was the development of radioactive holmium phosphate microspheres (HoPO₄-MS) with a high holmium content and that are stable in human serum for selective internal radiation therapy (SIRT) of liver cancer. To this end, holmium acetylacetonate microspheres (HoAcAc-MS) were prepared (34.2 ± 1.0 µm in diameter,...

journal article 2018

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Prediction of oxide phases formed upon internal oxidation of advanced high-strength steels

Mao, W. (author), Sloof, W.G. (author), Hendrikx, R.W.A. (author)

The effect of Cr on the oxidation of Fe–Mn-based steels during isothermal annealing at different dew points was investigated. The Fe–Mn–Cr–(Si) phase diagrams for oxidizing environments were computed to predict the oxide phases. Various Fe–Mn steels with different concentrations of Cr and Si were annealed at 950 °C in a gas mixture of Ar or N...

journal article 2017

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Learning about the opponent in automated bilateral negotiation: A comprehensive survey of opponent modeling techniques

Baarslag, T. (author), Hendrikx, M.J.C. (author), Hindriks, K.V. (author), Jonker, C.M. (author)

A negotiation between agents is typically an incomplete information game, where the agents initially do not know their opponent’s preferences or strategy. This poses a challenge, as efficient and effective negotiation requires the bidding agent to take the other’s wishes and future behavior into account when deciding on a proposal. Therefore, in...

journal article 2015

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Smoothing of X-ray diffraction data and K (alpha)2 elimination using penalized likelihood and the composite link model

De Rooi, J.J. (author), Van der Pers, N.M. (author), Hendrikx, R.W.A. (author), Delhez, R. (author), Bottger, A.J. (author), Eilers, P.H.C. (author)

X-ray diffraction scans consist of series of counts; these numbers obey Poisson distributions with varying expected values. These scans are often smoothed and the K2 component is removed. This article proposes a framework in which both issues are treated. Penalized likelihood estimation is used to smooth the data. The penalty combines the...

journal article 2014

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Optical characterization of gold-cuprous oxide interfaces for terahertz emission applications

Ramanandan, G.K.P. (author), Adam, A.J.L. (author), Ramakrishnan, G. (author), Petrik, P. (author), Hendrikx, R. (author), Planken, P.C.M. (author)

We show that the interface between gold and thermally formed cuprous oxide, which emits terahertz radiation when illuminated with ultrafast femtosecond lasers, is in fact an AuCu/Cu2O interface due to the formation of the thermal diffusion alloy AuCu. The alloy enables the formation of a Schottky-barrier-like electric field near the interface...

journal article 2014

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Enhanced terahertz emission by coherent optical absorption in ultrathin semiconductor films on metals

Ramakrishnan, G. (author), Ramanandan, G.K.P. (author), Adam, A.J.L. (author), Xu, M. (author), Kumar, N. (author), Hendrikx, R.W.A. (author), Planken, P.C.M. (author)

We report on the surprisingly strong, broadband emission of coherent terahertz pulses from ultrathin layers of semiconductors such as amorphous silicon, germanium and polycrystalline cuprous oxide deposited on gold, upon illumination with femtosecond laser pulses. The strength of the emission is surprising because the materials are considered to...

journal article 2013

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A diffracted-beam monochromator for long linear detectors in X-ray diffractometers with Bragg-Brentano parafocusing geometry

Van der Pers, N.M. (author), Hendrikx, R.W.A. (author), Delhez, R. (author), Böttger, A.J. (author)

A new diffracted-beam monochromator has been developed for Bragg-Brentano X-ray diffractometers equipped with a linear detector. The monochromator consists of a cone-shaped graphite highly oriented pyrolytic graphite crystal oriented out of the equatorial plane such that the parafocusing geometry is preserved over the whole opening angle of the...

journal article 2013

document

Decoupling Negotiating Agents to Explore the Space of Negotiation Strategies (extended abstract)

Baarslag, T. (author), Hindriks, K.V. (author), Hendrikx, M.J.C. (author), Jonker, C.M. (author)

conference paper 2012

document

Blijven of verhuizen? Minder leegstand door binding van de gebruiker

van der Voordt, D.J.M. (author), Remoy, H.T. (author), Hendrikx, T. (author)

Waarom besluit een deel van de gebruikers bij een discrepantie tussen vraag en aanbod tot ingrijpende renovatie en verhuizen andere gebruikers naar een bestaand of nieuw gebouw? Deze vraag is al decennia lang onderwerp van onderzoek, maar met de hoge leegstand van nu extra actueel. Dit artikel bespreekt de belangrijkste push- en pull-factoren.

journal article 2012

document

Duurzaamheid speelt grote rol bij besluitvorming: Renoveren of verhuizen?

van der Voordt, D.J.M. (author), Remoy, H.T. (author), Hendrikx, T. (author)

Waarom besluit een deel van de kantoorgebruikers bij een discrepantie tussen vraag en aanbod tot ingrijpende renovatie en verhuizen andere gebruikers naar een bestaand of nieuw gebouw? Dit artikel bespreekt de belangrijkste push- en pullfactoren die bij zo’n beslissing komen kijken. Opvallend is dat duurzaamheid in toenemende mate een rol speelt...

journal article 2012