The main research question of this thesis was: Can nitrogen cycling on dairy farms on peat soil in the Dutch Green Heart area be improved by adapting management to the nitrogen supply from soil and by using other grassland species and crops without affecting milk production?

De Vrouw Vennepolder bij Oud Ade is omgetoverd tot het Polderlab. Wetenschappers en studenten van de Universiteit Leiden onderzoeken hier samen met boeren en burgers hoe je veenweidegrond duurzaam en rendabel beheert. Een geweldige kans voor studenten om te ervaren hoe ze wetenschappelijke kennis kunnen…

The use of N fertilizers has increased worldwide in the past century. While this increased input of N has increased food productivity, it has also contributed to decreases in biodiversity, soil quality and environmental health, including increases in greenhouse gas emissions.

The elementary excitations of magnets are called spin waves, and their corresponding quasi-particles are known as magnons. The rapidly growing field of Magnonics aims at using them as information carriers in a new generation of electronic devices, (almost) free of electric currents.

This thesis comprises the development of reproducible synthesis procedures for two-dimensional materials (composed of boron, nitrogen and carbon) on different metallic surfaces.

This thesis focuses on developing wafer-scale two-dimensional (2D) materials by combining synthesis, transfer, characterization, and device integration of graphene, hexagonal boron nitride (h-BN), and BN-doped amorphous carbon.

Freshwater biodiversity has been threatened by eutrophication due to excessive nutrients in the environment. Releasing the freshwater species from such pressures requires efforts from industry and manufacturers to avoid emissions to vulnerable and high-risk regions.

Membrane fusion is a vital process in living organisms and is mediated by zipper-like proteins.

Promotor: T.J. Aartsma, Co-promotor: R.N. Frese

This thesis systematically studies the physicochemical properties of non-planar, propeller-shaped, polycyclic aromatic hydrocarbons. The synthesis of several so-called propellerenes is described on a gram scale, using optimized procedures aimed at using less hazardous reagents and reducing the amount…

Vinasse is a major by-product generated by the sugarcane biofuel industry. It is a source of microbes, nutrients and organic matter and often it is recycled as fertilizer.

Advanced sensing techniques require graphene with high quality and well-controlled surface chemistry.

Tin electrodeposition applications have rapidly evolved in the past 25 years.

Promotor: Prof.dr. H.V.J. Linnartz, Co-Promotores: S. Ioppolo, H.M. Cuppen

Planets are formed in disks of gas and dust around young stars.

Promotor: Prof.dr. M. Schilthuizen

This thesis explores interfacial conductance and electric field-effects in LaAlO3/SrTiO3 heterostructures.

De voedselproductie in Nederland is een economisch succes, maar heeft geleid tot veel milieuproblemen, waaronder stikstofvervuiling. Onlangs keurde de hoogste rechter het beleid af dat economische groei en vermindering van de stikstofverliezen combineerde. Hierdoor belandde het land in een stikstofcrisis.In…

Hoe zorgen we beter voor boer en aarde? In S&D, het tijdschrift van de Wiardi Beckman Stichting, proberen hoogleraar Jan Willem Erisman (Centrum Milieuwetenschappen Leiden) en landbouweconoom Krijn Poppe (Raad voor de leefomgeving en infrastructuur) deze vraag te beantwoorden.

hotocatalysis has emerged as a powerful tool for enabling challenging transformations in organic synthesis. This thesis explores the development of several photocatalytic reactions designed to form carbon-heteroatom bonds from less-functionalized precursors.

This thesis systematically analyzes the physical-chemistry of lipid-graphene interactions with the major objective of reconciliating the variety of results reported in the literature.

Aspergillus niger is an important industrial producer of organic acids and enzymes producing large amounts of spent fungal biomass.

Single-layer graphene (SLG) has attracted considerable interest as a proton exchange membrane for direct methanol fuel cells (DMFCs), owing to its atomic thickness, mechanical robustness, and unique proton permeability.

This thesis presents the results of a study on the interfaces of insulating oxides with and without the insertion of a magnetic layer.

This thesis investigates reactive interfaces in surface science across three domains: heterogeneous catalysis, environmental nanoplastics, and two-dimensional materials.

Consequences for sediment stability and seston trapping

The aromatic infrared bands (AIBs) seen throughout the interstellar medium (ISM) are generally thought to be carried by polycyclic aromatic hydrocarbons (PAHs) and their nitrogen analogues (PANHs).

Hot astrophysical plasma is ubiquitous in the Universe, from comets in our Solar system to the largest scale structures -- the cosmic web filaments. These hot plasmas, with the temperature of a few millions of degrees, are often observed in the X-ray wavelength range.

One of the key discoveries in exoplanet research over the past decade is the abundance of small planets in our Milky Way. Despite their high numbers, our understanding of their atmospheres remains limited, and it is unknown if they possess atmospheres at all.

There are many interpretations of quantum mechanics, and ultimately experiments are needed to verify or falsify these interpretations.

Catalysis is of extreme relevance in the production of everyday materials and plays a central role in many aspects of our life.

Streptomyces are prolific producers of enzymes and secondary metabolites, including more than 50% of all clinical antibiotics. This makes them highly attractive for medical, biotechnological, and industrial purposes.

Cell-based medicinal products (CBMPs), such as CAR T cells, are highly complex biopharmaceutical products offering various treatment options for serious illnesses such as cancer or autoimmune diseases.

A dense region of a gaseous and dusty cloud collapses to form a protostar surrounded by a disk and an envelope. This thesis uses both observations and models to study physical and chemical conditions of these protostellar systems which are likely where planets start to form.

Before the large scale use of renewable energy sources can be implemented in our society, the storage of electrical energy needs to be tackled. Storage the energy as hydrogen via the reduction of protons is a good option.

From surface science towards industrial practice using high-pressure scanning tunneling microscopy.

Promotors: Prof.dr. G.R. de Snoo, Prof.dr. G.A. Persoon, Prof.dr.ir. H.H. de Iongh

This thesis describes the synthesis and biochemical evaluation of a variety of cyclophellitol based activity-based probes and inhibitors targeting various endo- and exo-acting retaining glycosidases. In the last two decades a variety of probes and inhibitors for (hemi)cellulose degrading enzymes have…

Zeven dagen stikstof-arm leven, op excursie naar een veeboerderij en telkens nieuwe gastdocenten. Zo zien de weken eruit van masterstudenten die sinds begin oktober het keuzevak Nitrogen & Sustainability volgen. Het doel? Een oplossing vinden voor het Nederlandse stikfstofprobleem.

Naar aanleiding van de explosie in Beirut maakte BBC podcastserie 'The Foodchain' een aflevering over de chemische stof die de explosie veroorzaakte: ammoniumnitraat. Deze stof wordt veelvuldig gebruik in kunstmest. Met Hoogleraar Environmental sustainability Jan Willem Erisman spraken ze over de effecten…

Promotie

Universiteit Leiden is deel van een Nederlands consortium dat 4,7 miljoen euro van NWO ontvangt voor de bouw van een faciliteit die gecontroleerd dunne laagjes materiaal kan maken. De faciliteit kan kleine én grote lagen produceren en is daarmee uniek in de wereld. Zulke grote lagen zijn belangrijk…

Volume 72 of the Netherlands Yearbook for History of Art is dedicated to the relationship of art and death in the Low Countries and its diaspora, from premodern times to the present. The editors welcome contributions on works of art and architecture (paintings, prints, sculptures, objects of applied…

Chemicus Alexander Kros en astronoom Joop Schaye maken deel uit van de vier Leidse wetenschappers die dit jaar uit de Vernieuwingsimpuls van NWO een Vici toegekend hebben gekregen. Met deze subsidie van anderhalf miljoen kunnen ze een eigen onderzoeksgroep opzetten en promovendi aanstellen.

Tot nu toe verliepen processen van het maken van ‘dunne films’ – met toepassingen in bijvoorbeeld smartphones en zonnebrillen - volgens de ‘trial and error’-methode. Vincent Fokkema van het Leids Instituut voor Onderzoek in de Natuurkunde heeft nu een uniek instrument ontwikkeld waarmee de processen…

Het was al de meest aangehaalde publicatie die ooit bij onze faculteit is geschreven, maar nu is een nieuwe mijlpaal bereikt. Een artikel van emeritus hoogleraar Jan Reedijk - en co-auteurs - ging afgelopen maand over de 10.000 citaties heen. En de teller tikt door.

Het is een team van onderzoekers gelukt om een enkel spinnend elektron te positioneren op een chip met een precisie van enkele nanometers. Hiermee ligt de weg open naar quantumchips met nano-elementen naar keuze. De resultaten zijn gepubliceerd in het gerenommeerde Applied Physics Letters.