Papers by henrich frielinghaus
Assessment of the photodetection performance of different silicon photomultiplier technologies under irradiation with cold neutrons
2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), 2016
Results are presented of the opto-electrical characterization of two analog and one digital SiPM ... more Results are presented of the opto-electrical characterization of two analog and one digital SiPM arrays, produced by three different manufacturers (SensL, Hamamatsu, and Philips), before and after irradiation with cold neutrons (with a wavelength of 5 Å) at the KWS-1 instrument of the Heinz Maier-Leibnitz Zentrum (MLZ) in Garching, Germany. Irradiation doses of up to 6×1012 n/cm2 were used. We assessed the neutron irradiation induced changes in the temperature dependent dark signal and breakdown behaviors, as well as changes in the photodetection efficiency of the Philips Digital Photon Counting (PDPC) array. We conclude that all three technologies could be used in Small-Angle Neutron Scattering (SANS) experiments.
High crystallinity Li-rich porous materials integrating with an in-situ formed surface containing... more High crystallinity Li-rich porous materials integrating with an in-situ formed surface containing carbonaceous compounds are synthesized through a facile approach. The rationally designed procedure involves the formation of a specific morphology of a hydroxide precursor assisted by a self-made template and subsequent high temperature treatment to obtain Li1.2Mn0.56Ni0.16Co0.08O2 target product. The porous morphology is investigated using field-emission scanning electron microscopy and its surface area quantitatively examined by gas sorption analysis couple with the BrunauerEmmett–Teller method. The crystallinity is characterized by X-ray diffraction and high-resolution transmission electron microscopy. X-ray photoelectron spectroscopy, CHN element analysis and small angle neutron scattering confirm the presence of the carbonaceous compounds in the surface composition. The prepared material exhibits superior discharge rate capability and excellent cycling stability. It shows minor ca...
Polythiophene Based Block Copolymers for Neutron Scattering
Soft Matter Dynamics at the Solid-Liquid Interface Studied with Grazing Incidence Neutron Spin Echo Spectroscopy
Amphiphilic Comb Polymers as New Additives in Bicontinuous Microemulsions
Nanomaterials, 2020
It has been shown that the thermodynamics of bicontinuous microemulsions can be tailored via the ... more It has been shown that the thermodynamics of bicontinuous microemulsions can be tailored via the addition of various different amphiphilic polymers. In this manuscript, we now focus on comb-type polymers consisting of hydrophobic backbones and hydrophilic side chains. The distinct philicity of the backbone and side chains leads to a well-defined segregation into the oil and water domains respectively, as confirmed by contrast variation small-angle neutron scattering experiments. This polymer–microemulsion structure leads to well-described conformational entropies of the polymer fragments (backbone and side chains) that exert pressure on the membrane, which influences the thermodynamics of the overall microemulsion. In the context of the different polymer architectures that have been studied by our group with regards to their phase diagrams and small-angle neutron scattering, the microemulsion thermodynamics of comb polymers can be described in terms of a superposition of the backbon...
The phase diagram, the Flory-Huggins parameter Γ, and the Ginzburg parameter Gi of a polybutadien... more The phase diagram, the Flory-Huggins parameter Γ, and the Ginzburg parameter Gi of a polybutadiene/polystyrene blend and diblock copolymer were determined by small-angle neutron scattering in the pressure range of 0.1 and 200MPa. Both systems show qualitatively the same pressure dependence. The enthalpic and entropic terms of Γ are larger in blends. In the diblock copolymer a constant order-disorder temperature was observed which could be explained by a compensation effect between Γ and Gi.
Dark current performance of an analog SiPM array under irradiation with cold neutrons
A method for increasing the efficiency of surfactants, for widening the temperature window for suppressing lamellar mesophases in microemulsions by means of additives, as well as microemulsions
The invention relates to a method for increasing the efficiency of surfactants, for widening the ... more The invention relates to a method for increasing the efficiency of surfactants, for widening the temperature window for suppressing lamellar mesophases in microemulsions by means of additives as well as a chemical composition. According to the invention the microemulsions additives are added, which have at least one water-soluble and a hydrophobic moiety. The ratio of the number average molecular weight of water-soluble to hydrophobic units is from 2 to 1000, wherein the additives are polymers consisting of at least one water-soluble unit having at least at one chain end at least one hydrophobic unit and / or a hydrophobic unit as non-terminal substituents owns and / or at least one hydrophobic unit has, which is installed between the water-soluble units of the polymer.
Neutron Scattering on Different States of Polymer–Clay Compounds: From Solution to Dry States
Nanocomposites in general have gained importance in current products, leading to improved perform... more Nanocomposites in general have gained importance in current products, leading to improved performance of these complex compound materials. The structure of the solid particles is not limited in terms of shape in advance, but their specific function is tightly connected to their shape. Scattering experiments are often employed to supervise production routes and the final performance, but not all possibilities of scattering experiments are exploited due to several reasons: engineers need to enter the unknown stage of scattering experiments, and the scattering experts need to simplify their experience to simple, usable recipes that are applicable and reliable. This process is still ongoing, and the authors hope to contribute to this highly interesting journey.
Verfahren zur Aufweitung des Temperaturfensters in Mikroemulsionen mittels Additiven
Die Erfindung betrifft ein Verfahren zur Aufweitung des Temperaturfensters in Mikroemulsionen mit... more Die Erfindung betrifft ein Verfahren zur Aufweitung des Temperaturfensters in Mikroemulsionen mittels Additiven. Erfindungsgemas werden den Mikroemulsionen Additive zugefugt, welche mindestens eine wasserlosliche und eine hydrophobe Einheit besitzen. Das Verhaltnis des zahlenmittleren Molekulargewichtes von wasserloslichen zu hydrophoben Einheiten betragt von 2 bis 1000 wobei die Additive Polymere sind, welche aus mindestens einer wasserloslichen Einheit bestehen, die mindestens an einem Kettenende mindestens eine hydrophobe Einheit besitzt und/oder eine hydrophobe Einheit als nicht-terminalen Substituenten besitzt und/oder mindestens eine hydrophobe Einheit besitzen, welche zwischen den wasserloslichen Einheiten des Polymers eingebaut ist.
Journal of Applied Crystallography
Many experimental methods are available for the characterization of nanostructures, but most of t... more Many experimental methods are available for the characterization of nanostructures, but most of them are limited by stringent experimental conditions. When it comes to analysing nanostructures in the bulk or in their natural environment – even as ordinary as water at room temperature – small-angle scattering (SAS) of X-rays or neutrons is often the only option. The rapid worldwide development of synchrotron and neutron facilities over recent decades has opened unprecedented possibilities for using SAS in situ and in a time-resolved way. But, in spite of its huge potential in the field of nanomaterials in general, SAS is covered far less than other characterization methods in non-specialized curricula. Presented here is a rigorous discussion of small-angle scattering, at a technical level comparable to the classical undergraduate coverage of X-ray diffraction by crystals and which contains diffraction as a particular case.
05: Nanostructures Investigated by Small Angle Neutron Scattering
Tunable Hydrogels with Improved Viscoelastic Properties from Hybrid Polypeptides
Macromolecules
Stability of near-surface ordering of bicontinuous microemulsions in external shear-fields
Journal of Colloid and Interface Science
The lubrication effect of bicontinuous microemulsions describes a facilitated flow along hydrophi... more The lubrication effect of bicontinuous microemulsions describes a facilitated flow along hydrophilic planar surfaces because the fluid forms lamellar domains that can slide off along each other much better than randomly ordered domains. The applicability of this effect is based on the prerequisite of the lamellar structure not being destroyed by external shear-fields. In this paper, we demonstrate that the lamellar structure is highly stable for shear rates of up to 600 s-1 using neutron reflectivity and grazing incidence small angle neutron scattering experiments. The transition structure that consists of perforated lamellae is attacked by the flow, and the bicontinuous microemulsion comes closer to the solid interface when shear is applied. All of this verifies the stability of the lubrication effect for technical applications.
The bacterial Sec translocon, SecYEG, associates with accessory proteins YidC and the SecDF-YajC ... more The bacterial Sec translocon, SecYEG, associates with accessory proteins YidC and the SecDF-YajC subcomplex to form the bacterial holo-translocon (HTL). The HTL is a dynamic and flexible protein transport machine capable of coordinating protein secretion across the membrane, and efficient lateral insertion of nascent membrane proteins. It has been hypothesized that a central lipid core facilitates the controlled passage of membrane proteins into the bilayer, ensuring efficient formation of their native state. By performing small-angle neutron scattering (SANS) on protein solubilized in match-out deuterated detergent, we have been able to interrogate a naked HTL complex, with the scattering contribution of the surrounding detergent micelle rendered invisible. Such an approach has allowed the confirmation of a lipid core within the HTL, which accommodates between 8 and 29 lipids. Coarse-grained molecular dynamics simulations of the HTL also demonstrate a dynamic, central pool of lipid...
Influence of the amphiphilicity profile of copolymers on the formation of liquid crystalline mesophases in microemulsions
Colloid and Polymer Science, 2017
In bicontinuous microemulsions, the increase of the solubilization capacity of a surfactant, e.g.... more In bicontinuous microemulsions, the increase of the solubilization capacity of a surfactant, e.g., by the addition of amphiphilic block copolymers (“boosting effect”), is normally accompanied by the formation of liquid crystalline mesophases. We studied a new class of amphiphilic polymers as “boosters,” so-called gradient polymers, with a gradual change from the hydrophilic to the hydrophobic part. Phase diagram measurements and static and quasielastic neutron scattering experiments reveal that the polymers cause a stiffening of the amphiphilic film while simultaneously the saddle splay modulus decreases such that the formation of liquid crystalline mesophases, normally present with diblock polymers as “boosters,” is suppressed, while bicontinuous structures are geometrically favored. In addition, these findings are supported by theoretical calculations following the works of Lipowsky. Hence, gradient amphiphilic polymers not only increase the efficiency of surfactants but simultaneously suppress the formation of liquid crystalline phases thereby greatly increasing their application potential.
Method for Improving Efficacy of Surfactants Prevention of Lamellar Mesophases Temperature Stabilization of the Single Phase Region and a Method for Reducing Boundary Surface Tension in Micro-Emulsions Containing Silicone Oils by Means of Additives and Surfactant/Oil Mixtures
Synthesis and characterization of polystyrene chains on the surface of silica nanoparticles: comparison of SANS, SAXS, and DLS results
Colloid and Polymer Science, Apr 3, 2013
Journal of Physics Conference Series
Grazing Incidence Neutron Spin Echo Spectroscopy (GINSES) opens new possibilities for observing t... more Grazing Incidence Neutron Spin Echo Spectroscopy (GINSES) opens new possibilities for observing the thermally driven dynamics of macromolecules close to a rigid interface. The information about the dynamics can be retrieved as a function of scattering depth of the evanescent neutron wave, on the length scale in the range of some 10-100 nm. Using a classical neutron spin echo spectrometer with a laterally collimated beam, dynamics can be measured in grazing incidence geometry. We show examples of how the interface modifies the dynamics of microemulsions, membranes and microgels. Instrumental details and possible improvements for this technique will be presented. The key issue is the low intensity for dynamics measurements with an evanescent neutron wave. Conceptual questions how a specialised instrument could improve the experimental technique will be discussed.
Stabilizing the solid‐electrolyte interphase with polyacrylamide for high‐voltage aqueous lithium‐ion batteries
Angewandte Chemie International Edition
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Papers by henrich frielinghaus