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Dependence of impact regime boundaries on the initial temperatures of projectiles and targets

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Defence Technology（防务技术） 2024年第1期31卷 49-57页

作者： Stefano Signetti andreas Heine Fraunhofer-Institut für Kurzzeitdynamik Ernst-Mach-InstitutEMIErnst-Zermelo-Str.479104 Freiburg im BreisgauGermany

Towards higher impact velocities,ballistic events are increasingly determined by the material temperatures.Related effects might range from moderate thermal softening to full phase transition.In particular,it is of great interest to quantify the conditions for incipient or full melting of metals during impact interactions,which result in a transition from still strength-affected to hydrodynamic material behavior.In this work,we investigate to which extent the respective melting thresholds are also dependent on the initial,and generally elevated,temperatures of projectiles and targets before impact.This is studied through the application of a model developed recently by the authors to characterize the transition regime between high-velocity and hypervelocity impact,for which the melting thresholds of materials were used as the defining quantities.The obtained results are expected to be of general interest for ballistic application cases where projectiles or targets are preheated.Such conditions might result,for example,from aerodynamic forces acting onto a projectile during atmospheric flight,explosive shapedcharge-jet formation or armor exposure to environmental conditions.The performed analyses also broaden the scientific understanding of the relevance of temperature in penetration events,generally known since the 1960s,but often not considered thoroughly in impact studies.

关键词： Ballistic impact Thermal effects Metallic targets Energy partitioning Homologous temperature

The interaction between a shaped charge jet and a single moving plate

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Defence Technology（防务技术） 2024年第1期31卷 1-13页

作者： andreas Helte Jonas Lundgren Jonas Candle FOI WeaponsProtection and SecuritySE-16490StockholmSweden

Reactive armour is a very efficient add-on armour against shaped charge threats.Explosive reactive armour consists of one or several plates that are accelerated by an explosive.Similar but less violent acceleration of plates can also be achieved in a completely inert reactive armour.To be efficient against elongated jets,the motion of the plates needs to be inclined against the jet such that a sliding contact between the jet and the plates is established.This sliding contact causes a deflection and thinning of the jet.Under certain circumstances,the contact will become unstable,leading to severe disturbances on the jet.These disturbances will drastically reduce the jet penetration performance and it is therefore of interest to study the conditions that leads to an unstable contact.Previous studies on the interaction between shaped charge jets and flyer plates have shown that it is mainly the forward moving plate in an explosive reactive armour that is effective in disturbing the jet.This is usually attributed to the higher plate-to-jet mass flux ratio involved in the collision of the forward moving plate compared to the backward moving plate.For slow moving plates,as occurs in inert reactive armour,the difference in mass flux for the forward and backward moving plate is much lesser,and it is therefore of interest to study if other factors than the mass flux influences on the protection capability.In this work,experiments have been performed where a plate is accelerated along its length,interacting with a shaped charge jet that is fired at an oblique angle to the plate’s normal,either against or along the plate’s velocity.The arrangement corresponds to a jet interacting with a flyer plate from a reactive armour,with the exception that the collision velocity is the same for both types of obliquities in these experiments.The experiments show that disturbances on the jet are different in the two cases even though the collision velocities are the same.Numerical simulations of the interaction support the observation.Th

关键词： Reactive armour Flyer plate Shaped charge jet

Note on:“Ballistic model for the prediction of penetration depth and residual velocity in adobe:A new interpretation of the ballistic resistance of earthen masonry”

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Defence Technology（防务技术） 2024年第1期31卷 607-609页

作者： andreas Heine Matthias Wickert Fraunhofer EMI Ernst-Zermelo-Str.479104FreiburgGermany

A recently published modeling approach for the penetration into adobe and previous approaches implicitly criticized are reviewed and discussed.This article contains a note on the paper titled“Ballistic model for the prediction of penetration depth and residual velocity in adobe:A new interpretation of the ballistic resistance of earthen masonry”(DOI:https://***/10.1016/j.dt.2018.07.017).Reply to the Note from Li Piani et al is linked to this article.

关键词： adobe prediction earth

Cholesterol business:lifeor death byrust

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1247-1248页

作者： Shubhangi Gavalil Francesca Maremonti andreas Linkermann Division of Nephrology Department of Internal Medicine 3University Hospital Carl Gustav Carus at the Technische Universitat DresdenDresdenGermany Division of Nephrology Department of MedicineAlbert Einstein College of MedicineBronxNYUSA

In two recent manuscripts published in Nature,the cholesterol-synthesis pathway was identified as a master regulator of ferroptosis sensitivity and therefore as a novel therapeutic target.1,2 Ferroptosis does not only represent one way to eliminate cancer cells,but also contributes to acute organ damage in the kidney,heart,brain,and liver,and it kills tissues during the process of organ transplantation.The term“ferroptosis”should be defined as a cellular process of iron-catalyzed lipid peroxidation-mediated rupture of the plasma membrane.

关键词： rupture death damage

Odd-even effects in the structure and properties of aryl-substituted aliphatic self-assembled monolayers

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Nano Research 2024年第5期17卷 4231-4243页

作者： Piotr Cyganik andreas Terfort Michael Zharnikov Jagiellonian University Faculty of PhysicsAstronomy and Applied Computer ScienceSmoluchowski Institute of PhysicsŁojasiewicza 1130-348 KrakówPoland Institut für Anorganische und Analytische Chemie Universität FrankfurtMax-von-Laue-Straße 760438 FrankfurtGermany Applied Physical Chemistry Heidelberg UniversityIm Neuenheimer Feld 25369120 HeidelbergGermany

Self-assembled monolayers(SAMs)represent an important tool in context of nanofabrication and molecular engineering of surfaces and interfaces.The properties of functional SAMs depend not only on the character of the tail groups at the SAM-ambient interface,but are also largely defined by their structure.In its turn,the latter parameter results from a complex interplay of the structural forces and a variety of other factors,including so called odd-even effects,viz.dependence of the SAM structure and properties on the parity of the number(odd or even)of individual building blocks in the backbone of the SAM constituents.The most impressive manifestation of the odd-even effects is the structure of aryl-substituted alkanethiolate SAMs on Au(111)and Ag(111),in which,in spite of the fact that the intermolecular interaction is mostly determined by the aryl part of the monolayers,one observes a pronounced dependence of molecular inclination and,consequently,the packing density of the SAM-forming molecules on the parity of number of methylene units in the alkyl linker.Here we review the properties of the above systems as well as address fundamental reasons behind the odd-even effects,including the existence of a so-called bending potential,which is frequently disregarded in analysis of the structure-building forces.The generality of the odd-even effects in SAMs is additionally supported by the recent data for SAMs on GaAs,scanning tunneling microscopy data for SAMs on Ag(111),and the data for the monolayers with selenolate and carboxyl anchoring groups on Au(111)and Ag(111).The implications of these effects in terms of the control over the packing density and orientation of the tail groups at the SAM-ambient interface,structural perfection,polymorphism,temperature-driven phase transitions,and SAM stability toward such factors as ionizing radiation,exchange reaction,and electrochemical desorption are discussed.These implications place the odd-even effects as an important tool for the design of functional SAMs in context of

关键词： self-assembled monolayers molecular films surface and interface engineering odd-even-effects

Optimal Offering of Energy Storage in UK Day-Ahead Energy and Frequency Response Markets

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 415-426页

作者： Makedon Karasavvidis andreas Stratis Dimitrios Papadaskalopoulos Goran Strbac Department of Electrical and Electronic Engineering Imperial College LondonLondonUK Statkraft UK Ltd. LondonUK Department of Electrical and Computer Engineering University of PatrasPatrasGreece IEEE

The offering strategy of energy storage in energy and frequency response(FR) markets needs to account for country-specific market regulations around FR products as well as FR utilization factors, which are highly uncertain. To this end, a novel optimal offering model is proposed for stand-alone price-taking storage participants, which accounts for recent FR market design developments in the UK, namely the trade of FR products in time blocks, and the mutual exclusivity among the multiple FR products. The model consists of a day-ahead stage, devising optimal offers under uncertainty, and a real-time stage, representing the storage operation after uncertainty is materialized. Furthermore, a concrete methodological framework is developed for comparing different approaches around the anticipation of uncertain FR utilization factors(deterministic one based on expected values, deterministic one based on worst-case values, stochastic one, and robust one), by providing four alternative formulations for the real-time stage of the proposed offering model, and carrying out an out-of-sample validation of the four model instances. Finally, case studies employing real data from UK energy and FR markets compare these four instances against achieved profits, FR delivery violations, and computational scalability.

关键词： Energy markets energy storage frequency response optimal offering robust optimization stochastic programming

Differential roles of C-3 and C-6 phosphate monoesters in affecting potato starch properties

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Grain & Oil Science and Technology 2024年第2期7卷 79-86页

作者： Li Ding andreas Blennow Yuyue Zhong Department of Plant and Environmental Sciences Faculty of ScienceUniversity of CopenhagenDenmark Department of Sustainable and Bio-inspired Materials Max-Planck Institute of Colloids and InterfacesPotsdamGermany

The effects of starch phosphate monoester content(SPC),namely C-3(C3P)and C-6 phosphate monoesters(C6P),on the starch properties were investigated using four potato starches with varied SPC/C3P/C6P and two nonphosphorylated maize starches with a similar range of amylose content(AC)as controls.The starch property results showed that a higher SPC is associated with lower turbidity,storage and loss modulus after storage,and water solubility,but higher swelling power(SP)and pasting viscosities.These findings suggested that SPC inhibited molecular rearrangement during storage and starch leaching during heating,and enhanced swelling and viscosities due to increased hydration and water uptake caused by the repulsion effect of phosphate groups and a less ordered crystalline structure.Increased SPC also resulted in lower resistant starch(RS)content in a native granular state but higher RS after retrogradation.Pearson correlations further indicated that SPC/C3P/C6P were positively correlated with peak(r^(2)=0.925,0.873 and 0.930,respectively),trough(r^(2)=0.994,0.968 and 0.988,respectively),and final viscosities(r^(2)=0.981,0.968 and 0.971,respectively).Notably,SPC,mainly C3P,exhibited a significantly positive correlation with SP(r^(2)=0.859)and setback viscosity(r^(2)=0.867),whereas SPC,mainly C6P,showed a weak positive correlation with RS after retrogradation(r^(2)=0.746).However,SPC had no significant correlations with water solubility,turbidity and rheology properties,which were more correlated with AC.These findings are helpful for the food industry to select potato starches with desired properties based on their contents of SPC,C3P,or C6P.

关键词： Starch phosphate monoesters C-3 phosphate monoesters C-6 phosphate monoesters Physicochemical properties In vitro digestibility

MXene-Based Elastomer Mimetic StretchableSensors: Design, Properties, and Applications

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Nano-Micro Letters 2024年第7期16卷 295-342页

作者： Poushali Das Parham Khoshbakht Marvi Sayan Ganguly Xiaowu(Shirley)Tang Bo Wang Seshasai Srinivasan Amin Reza Rajabzadeh andreas Rosenkranz School of Biomedical Engineering McMaster University1280 Main Street WestHamiltonON L8S 4L8Canada Department of Chemistry and Waterloo Institute for Nanotechnology(WIN) University of Waterloo200 University Ave WestWaterlooONCanada Centre for Eye and Vision Research(CEVR) 17W Hong Kong Science ParkShatinHong KongPeople’s Republic of China Chair of Functional Materials Department of Materials Science and EngineeringSaarland UniversitySaarbruckenGermany W Booth School of Engineering Practice and Technology McMaster University1280 Main Street WestHamiltonON L8S 4L7Canada Department for Chemical Engineering Biotechnology and MaterialsUniversity of ChileSantiagoChile

Flexible sensors based on MXene-polymer composites are highly prospective for next-generation wearable electronics used in human-machine interfaces.One of the motivating factors behind the progress of flexible sensors is the steady arrival of new conductive materials.MXenes,a new family of 2D nanomaterials,have been draw-ing attention since the last decade due to their high electronic conduc-tivity,processability,mechanical robustness and chemical tunability.In this review,we encompass the fabrication of MXene-based polymeric nanocomposites,their structure-property relationship,and applications in the flexible sensor domain.Moreover,our discussion is not only lim-ited to sensor design,their mechanism,and various modes of sensing platform,but also their future perspective and market throughout the world.With our article,we intend to fortify the bond between flexible matrices and MXenes thus promoting the swift advancement of flexible MXene-sensors for wearable technologies.

关键词： Flexible sensor 2D nanomaterials MXene Wearable and conductive Applications

Food intolerance and the few-foods(or oligoantigenic)diet in children with attention-deficit hyperactivity disorder

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Food Science and Human Wellness 2024年第4期13卷 1729-1738页

作者： Klaus W.Lange andreas Reissmann Yukiko Nakamura Katharina M.Lange Faculty of Human Sciences University of RegensburgRegensburg 93040Germany Department of Psychology University of BathBath BA27AYUnited Kingdom

The hypothesis that some children with attention-deficit hyperactivity disorder(ADHD)may show sensitivity or allergic reactions to various food items has led to the development of the the few-foods(or oligoantigenic)diet.The rationale of the diet is to eliminate certain foods from the diet in order to exclude potential allergens contained either naturally in food or in artificial ingredients with allergenic properties.The oligoantigenic diet attempts to identify individual foods to which a person might be sensitive.First,ADHD symptoms are monitored while multiple foods are excluded from the diet.Subsequently,if symptoms remit,foods are re-introduced,while observing the individual for the return of symptoms.An advantage of the oligoantigenic diet is that it can be tailored to the individual.A growing body of evidence suggests that behavioral symptoms of subgroups of children with ADHD may benefit from the elimination of certain foods.The effect sizes of an oligoantigenic diet regarding improvement of ADHD symptoms have been found to be medium to large.Available evidence suggests that the investigation of the role of food hypersensitivities in ADHD is a promising avenue worthy of further exploration.Further large-scale,randomized controlled studies including assessment of long-term outcome are therefore warranted.

关键词： Attention-deficit hyperactivity disorder Food intolerance Few-foods diet Etiology Treatment