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Unexpected Twinning and Phase-Transition of the Indentation Standards, Their Transition Energies, and Scientific Dichotomy

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Journal of Applied Mathematics and Physics 2024年第6期12卷 2119-2159页

作者： gerd Kaupp Department of Chemistry University of Oldenburg Oldenburg Germany

The general use of aluminium as an indentation standard for the iteration of contact heights for the determination of ISO-14577 hardness and elastic modulus is challenged because of as yet not appreciated phase-changes in the physical force-depth standard curve that seemed to be secured by claims from 1992. The physical and mathematical analyses with closed formulas avoid the still world-wide standardized energy-law violation by not reserving 33.33% (h2 belief) (or 20% h3/2 physical law) of the loading force and thus energy for all not depth producing events but using 100% for the depth formation is a severe violation of the energy law. The not depth producing part of the indentation work cannot be done with zero energy! Both twinning and structural phase-transition onsets and normalized phase-transition energies are now calculated without iterations but with physically correct closed arithmetic equations. These are reported for Berkovich and cubecorner indentations, including their comparison on geometric grounds and an indentation standard without mechanical twinning is proposed. Characteristic data are reported. This is the first detection of the indentation twinning of aluminium at room temperature and the mechanical twinning of fused quartz is also new. Their disqualification as indentation standards is established. Also, the again found higher load phase-transitions disqualify aluminium and fused quartz as ISO-ASTM 14577 (International Standardization Organization and American Society for Testing and Materials) standards for the contact depth “hc” iterations. The incorrect and still world-wide used black-box values for H- and Er-values (the latter are still falsely called “Young’s moduli” even though they are not directional) and all mechanical properties that depend on them. They lack relation to bulk moduli from compression experiments. Experimentally obtained and so published force vs depth parabolas always follow the linear FN = kh3/2 + Fa equation, where

关键词： Aluminium Fused Quartz Copper Twinning Structural Phase-Transitions Undue Indentation Standards Data Manipulation ZerodurR Absolute Hardness

Highly Luminescent Positively Charged Quantum Dots Interacting with Proteins and Cells

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Chinese Journal of Chemistry 2022年第22期40卷 2685-2693页

作者： Haixia Wang Karin Nienhaus Li Shang gerd Ulrich Nienhaus Institute of Applied Physics Karlsruhe Institute of Technology(KIT)76131 KarlsruheGermany Institute of Nanotechnology Karlsruhe Institute of Technology(KIT)76344 Eggenstein-LeopoldshafenGermany InstituteofBiologicaland Chemical Systems Karlsruhe Institute of Technology(KIT)76344 Eggenstein-LeopoldshafenGermany Department of Physics University of llinois at Urbana-ChampaignUrbanaIL61801USA Present address:Laboratory of Biomaterials and Translational Medicine Center for NanomedicineThe Third Affiliated HospitalSun Yat-sen UniversityGuangzhou510630China Present address:School of Materials Science and Engineering Northwestern PolytechnicalUniversityXi'an 710072China

We have studied interactions between positively charged MUTAB-stabilized quantum dots(QDs)and model proteins,serum and live cells using fluorescence correlation spectroscopy(FCS),dynamic light scattering(DLS),time-resolved photoluminescence(PL)and live-cell fluorescence *** human serum albumin(HSA)as a model protein,we measured the growth of a protein adsorption layer(“protein corona”)via time-resolved *** formation was characterized by an apparent equilibrium dissociation coefficient,KD≈10μ*** adlayer growth was surprisingly slow(timescale ca.30 min),in stark contrast to many similar measurements with HSA and other proteins and different ***-resolved PL data revealed a characteristic quenching behavior depending on the QD surface coverage with *** together,we found that MUTAB-QDs initially bind HSA molecules weakly(KD≈700μM);however,the affinity is enhanced over time,presumably due to proton injection into the MUTAB layer by HSA triggering ligand *** process was also observed with human blood serum,showing equal kinetics for comparable HSA ***,imaging experiments with cultured human cells(HeLa)revealed that MUTAB-QDs bind to the cell membrane and perforate *** process is reduced upon pre-adsorption of proteins on the MUTAB-QD.

关键词： Quantum dots Nanoparticles Agglomeration Protein adsorption Quantitative fluorescence microscopy

Reflections about the holographic and nonholographic acquisition of surface topography: where are the limits?

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Light(Advanced Manufacturing) 2022年第2期3卷 48-57页

作者： gerd Häusler Florian Willomitzer University of Erlangen Nuremberg Institute of OpticsInformationand Photonics91058 ErlangenGermany Northwestern University Department of Electrical and Computer EngineeringEvanston 60208USA

Recording and(computational)processing of complex wave fields offer a vast realm of new methods for optical 3D *** discuss fundamental similarities and differences between holographic surface topography measurement and non-holographic principles,such as triangulation,classical interferometry,rough surface interferometry and slope measuring *** features are the physical origin of the ultimate uncertainty limit and how the topographic information is encoded and *** the theoretical insight,the discussion will help optical metrologists to determine if their measurement results could be improved or have already hit the ultimate limit of what physics allows.

关键词： Optical metrology Topography Physical limits Holography

Prediction of exchangeable potassium in soil through mid-infrared spectroscopy and deep learning:From prediction to explainability

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Artificial Intelligence in Agriculture 2022年第1期6卷 230-241页

作者： Franck Albinet Yi Peng Tetsuya Eguchi Erik Smolders gerd Dercon Independent Researcher&Consultant GuétharyFrance Soil and Water Management&Crop Nutrition Laboratory Joint FAO/IAEA Centre of Nuclear Techniques in Food and AgricultureSeibersdorfAustria Global Soil Partnership Food and Agriculture Organization of the United NationsViale delle Terme di Caracalla00153 RomeItaly Agricultural Radiation Research Center Tohoku Agricultural Research CenterNational Agriculture and Food Research OrganizationFukushimaJapan Soil and Water Management Unit KU LeuvenBelgium

The ability to characterize rapidly and repeatedly exchangeable potassium(Kex)content in the soil is essential for optimizing remediation of radiocaesium contamination in *** this paper,we show how this can be now achieved using a Convolutional Neural Network(CNN)model trained on a large Mid-Infrared(MIR)soil spectral library(40,000 samples with Kex determined with 1 M NH4OAc,pH 7),compiled by the National Soil Survey Center of the United States Department of *** Partial Least Squares Regression as a base-line,we found that our implemented CNN leads to a significantly higher prediction performance of Kex when a large amount of data is available(10000),increasing the coefficient of determination from 0.64 to 0.79,and reducing the Mean Absolute Percentage Error from 135%to 31%.Furthermore,in order to provide end-users with required interpretive keys,we implemented the GradientShap algorithm to identify the spectral regions considered important by the model for predicting *** in the context of the implemented CNN on various Soil Taxonomy Orders,it allowed(i)to relate the important spectral features to domain knowledge and(ii)to demonstrate that including all Soil Taxonomy Orders in CNN-based modeling is beneficial as spectral features learned can be reused across different,sometimes underrepresented orders.

关键词： High-throughput soil characterization Machine learning Convolutional neural network Agriculture Nuclear emergency response Remediation Interpretability

Highly sensitive microfiber ultrasound sensor for photoacoustic imaging

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Opto-Electronic Advances 2023年第6期6卷 4-6页

作者： Perry Ping Shum gerd Keiser Georges Humbert Dora Juan Juan Hu APing Zhang Lei Su Department of Electronic and Electrical Engineering Southern University of Science and Technology1088 Xueyuan AvenueShenzhen 518055China Department of Electrical and Computer Engineering Boston University8 Saint Mary's StreetBoston 02215America XLIM Research Institute-UMR 7252 CNRS University of Limoges123avenue Albert ThomasLimoges 87060France Institute for Infocomm Research Agency for ScienceTechnology and Research1 Fusionopolis Way#21-01Connexis South Tower Singapore 138632Singapore The Hong Kong Polytechnic University Kowloon TongHong Kong 999077China School of Engineering and Materials Science Queen Mary University of LondonMile End RoadLondon E14NSUK

An ultrasound wave is a kind of acoustic signal with a frequency greater than 20 kHz,which is widely used in diverse fields such as medical imaging diagnosis,nondestructive testing and resource exploration.A variety of ultrasound sensors have been developed for ultrasound *** for photoacoustic imaging,specialized ultrasound sensors with high sensitivity,small size,and broad bandwidth are ***,achieving such sensor perform-ance still poses a great challenge to the current state-of-the-art in ultrasound sensor technology.A recent work pub-lished in Opto-Electronic Advances(DOI:10.29026/oea.2022.200076)proposes a microfiber-based ultrasound sensor that breaks the limitations of existing ultrasound *** from the large evanescent field characteristic of mi-crofiber,combined with the coherent detection technology,the proposed sensor realized highly sensitive ultrasound de-tection and demonstrated excellent performance in high-resolution photoacoustic *** highly sensitive and mini-aturized microfiber ultrasound sensor provides a competitive alternative for various applications,such as endoscopic photoacoustic imaging of the intestinal tract and blood vessels in animals.

关键词： Highly sensor competitive

Suicidal behavior-advances in clinical and neurobiological research and improvement of prevention strategies

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World Journal of Psychiatry 2022年第9期12卷 1115-1126页

作者： Thomas Sobanski Gregor Peikert Ulrich W Kastner gerd Wagner Department of Psychiatry Psychotherapyand Psychosomatic MedicineTHUERINGEN-Kliniken GmbHSaalfeld 07318Germany Network for Suicide Prevention in Thuringia(NeST) Jena 07743Germany Department of Psychiatry and Psychotherapy University Hospital JenaJena 07743Germany Department of Psychiatry and Psychotherapy Helios Fachkliniken HildburghausenHildburghausen 98646Germany

Suicide is the 14^(th)leading cause of death *** is responsible for 1%-5%of all *** article highlights the latest developments in universal,selective,and indicated prevention *** universal suicide prevention,current research has shown that strategies such as restricting access to lethal means(e.g.,control of analgesics and hot-spots for suicide by jumping)and school-based awareness programs are most *** selective prevention,substantial progress can be expected in psychological screening methods for suicidal *** measurement of implicit cognition proved to be more valid in predicting future suicide attempts than classic clinical *** developments are smartphone-based interventions and realtime monitoring of suicidal *** effort has been made to establish valid neurobiological screening methods(e.g.,genetic and epigenetic risk factors for suicide,hypothalamic-pituitary-adrenal axis)without yielding a major ***,multiple biomarkers rather than a single one are necessary to identify individuals at *** regard to indicated prevention in form of psychopharmacological treatment,recent pharmacoepidemiological studies and meta-analyses have supported a protective role of antidepressants,lithium,and ***,the data concerning a specific anti-suicidal effect of these drugs are currently not *** results exist for ketamine in reducing suicidal ideation,independently of its antidepressant *** psychotherapy,recent findings suggest that psychotherapeutic interventions specifically designed to prevent suicide re-attempts are most ***,cognitive behavioral therapy and psychodynamic therapy approaches proved to decrease the number of suicide re-attempts significantly.

关键词： Antidepressants Biomarkers Cognitive behavioral therapy Ketamine Prevention Suicide

Facile synthesis of ( β -chlorodifluoroethyl)phosphonates via chlorination reaction of difluoroalkyl diazo derivatives with HCl

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Chinese Chemical Letters 2022年第5期33卷 2429-2432页

作者： Jiang Liu Romana Pajkert Li Wang Haibo Mei gerd-Volker Röschenthaler Jianlin Han Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing 210037China Department of Life Sciences and Chemistry Jacobs University Bremen gGmbHCampus Ring 1Bremen 28759Germany

An efficient chlorination reaction of in situ generated(β-diazo-α,α-difluoroethyl)phosphonates has been achieved with hydrochloric acid as a chlorine source under mild and operationally convenient *** reaction does not need any catalyst and tolerates a wide scope of substrates,which affords the(β-chlorodifluoroethyl)phosphonate products in good to excellent *** reaction represents the first example of the halogenation of difluoroalkyl diazo compounds,and also provides an easy way for the synthesis of difluoromethylenephosphonate-containing compounds.

关键词： Difluorodiazoethane (β-Diazo-α,α-difluoroethyl)phosphonates Halogenation reaction Difluoroalkyl diazo Hydrochloric acid Masked carbene

The Non-Equivalence of Pyramids and Their Pseudo-Cones: Important New Insights

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Journal of Applied Mathematics and Physics 2022年第4期10卷 1158-1166页

作者： gerd Kaupp University of Oldenburg Oldenburg Germany

The simulation of indentations with so called “equivalent” pseudo-cones for decreasing computer time is challenged. The mimicry of pseudo-cones having equal basal surface and depth with pyramidal indenters is excluded by basic arithmetic and trigonometric calculations. The commonly accepted angles of so called “equivalent” pseudo-cones must not also claim equal depth. Such bias (answers put into the questions to be solved) in the historical values of the generally used half-opening angles of pseudo-cones is revealed. It falsifies all simulations or conclusions on that basis. The enormous errors in the resulting hardness HISO and elastic modulus Er-ISO values are disastrous not only for the artificial intelligence. The straightforward deduction for possibly ψ-cones (ψ for pseudo) without biased depths’ errors for equal basal surface and equal volume is reported. These ψ-cones would of course penetrate much more deeply than the three-sided Berkovich and cube corner pyramids (r a/2), and their half-opening angles would be smaller than those of the respective pyramids (reverse with r > a/2 for four-sided Vickers). Also the unlike forces’ direction angles are reported for the more sideward and the resulting downward directions. They are reflected by the diameter of the parallelograms with length and off-angle from the vertical axis. Experimental loading curves before and after the phase-transition onsets are indispensable. Mimicry of ψ-cones and pyramids is also quantitatively excluded. All simulations on their bases would also be dangerously invalid for industrial and solid pharmaceutical materials.

关键词： Basic Mathematics Extreme Errors False Cone Angles Indentation Unphysical Cone Models for Pyramids Undue Simulations

Exciting News from Indentations onto Silicon, Copper, and Tungsten

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Journal of Applied Mathematics and Physics 2023年第12期11卷 4042-4078页

作者： gerd Kaupp Department of Chemistry University of Oldenburg Oldenburg Germany

Indentations onto crystalline silicon and copper with various indenter geometries, loading forces at room temperature belong to the widest interests in the field, because of the physical detection of structural phase transitions. By using the mathematically deduced FNh3/2 relation for conical and pyramidal indentations we have a toolbox for deciding between faked and experimental loading curves. Four printed silicon indentation loading curves (labelled with 292 K, 260 K, 240 K and 210 K) proved to be faked and not experimental. This is problematic for the AI (artificial intelligence) that will probably not be able to sort faked data out by itself but must be told to do so. High risks arise, when published faked indentation reports remain unidentified and unreported for the mechanics engineers by reading, or via AI. For example, when AI recommends a faked quality such as “no phase changes” of a technical material that is therefore used, it might break down due to an actually present low force, low transition energy phase-change. This paper thus installed a tool box for the distinction of experimental and faked loading curves of indentations. We found experimental and faked loading curves of the same research group with overall 14 authoring co-workers in three publications where valid and faked ones were next to each other and I can thus only report on the experimental ones. The comparison of Si and Cu with W at 20-fold higher physical hardness shows its enormous influence to the energies of phase transition and of their transition energies. Thus, the commonly preferred ISO14577-ASTM hardness values HISO (these violate the energy law and are simulated!) leads to almost blind characterization and use of mechanically stressed technical materials (e.g. airplanes, windmills, bridges, etc). The reasons are carefully detected and reported to disprove that the coincidence or very close coincidence of all of the published loading curves from 150 K to 298

关键词： Phase-Transition-Onset and -Energy Indentation of Silicone Copper Copper Nanoparticles Tungsten with Polymorphs Low-Temperature Indentations Detection of Faked Loading Curves Protection of AI from False Advices Risk of Catastrophic Crashes Physical Hardness Exothermic Copper-Transitions Algebraic Calculations Negative-Standard-Energy Polymorphs