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Effect of solution treatment on the microstructure,phase transformation behavior and functional properties of NiTiNb ternary shape memory alloys fabricated via laser powder bed fusion in-situ alloying

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International Journal of Extreme Manufacturing 2024年第4期6卷 202-223页

作者： Rui Xi hao Jiang Guichuan Li Zhihui Zhang huiliang Wei Guoqun Zhao jan Van humbeeck Xiebin Wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJingshi Road 17923Jinan 250061People's Republic of China Department of Materials Engineering University of Leuven(KU Leuven)Kasteelpark Arenberg 44 bus 2450Heverlee B3001Belgium Key Laboratory of Bionic Engineering(Ministry of Education) Jilin UniversityRenmin Street 5988Changchun 130025People's Republic of China School of Mechanical Engineering Nanjing University of Science and TechnologyXiaolingwei Street 200Nanjing 210094People's Republic of China

Post-heat treatment is commonly employed to improve the microstructural homogeneity and enhance the mechanical performances of the additively manufactured metallic *** this work,a ternary(NiTi)91Nb9(at.%)shape memory alloy was produced by laser powder bed fusion(L-PBF)using pre-alloyed NiTi and elemental Nb *** effect of solution treatment on the microstructure,phase transformation behavior and mechanical/functional performances was *** in-situ alloyed(NiTi)91Nb9 alloy exhibits a submicron cellular-dendritic structure surrounding the supersaturated B2-NiTi *** high-temperature(1273 K)solution treatment,Nb-rich precipitates were precipitated from the supersaturated *** fragmentation and spheroidization of the NiTi/Nb eutectics occurred during solution treatment,leading to a morphological transition from mesh-like into rod-like and *** of theβ-Nb phases occurred with increasing holding *** martensite transformation temperature increases after solution treatment,mainly attributed to:(i)reduced lattice distortion due to the Nb expulsion from the supersaturated B2-NiTi,and(ii)the Ti expulsion from theβ-Nb phases that lowers the ratio Ni/Ti in the B2-NiTi matrix,which resulted from the microstructure changes from non-equilibrium to equilibrium *** thermal hysteresis of the solutionized alloys is around 145 K after 20%pre-deformation,which is comparable to the conventional NiTiNb alloys.A short-term solution treatment(*** 1273 K for 30 min)enhances the ductility and strength of the as-printed specimen,with the increase of fracture stress from(613±19)MPa to(781±20)MPa and the increase of fracture strain from(7.6±0.1)%to(9.5±0.4)%.Both the as-printed and solutionized samples exhibit good tensile shape memory effects with recovery rates>90%.This work suggests that post-process heat treatment is essential to optimize the microstructure and improve the mechanical performances of the L-PBF in-situ allo

关键词： shape memory alloy NiTiNb laser powder bed fusion in-situ alloying heat treatment

Geochronology and Petrogenesis of Late Carboniferous to Early Permian Basalts in the Central Lhasa Subterrane, Southern Tibet: Implications for the Evolution of the Sumdo Paleo-Tethys Ocean

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 955-968页

作者： MA Wang LIU Yingchao YANG Zhusen jan-Marten hUIZENGA LI Zhenqing YUE Longlong ZhAO Sibo School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Institute of Geology Sinoprobe LaboratoryChinese Academy of Geological SciencesBeijing 100037China MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life SciencesNO-1432ÅsNorway Economic Geology Research Centre(EGRU) College of Science and EngineeringJames Cook UniversityTownsvilleQueensland 4811Australia Department of Geology University of JohannesburgAuckland Park 2006South Africa

Basalts from the Late Carboniferous to Early Permian are extensively developed in the central Lhasa subterrane, southern Tibet. Studying the petrogenesis of these rocks may have implications for the late Paleozoic arc magmatism along the central Lhasa subterrane uncovering more of the evolution of the Sumdo Paleo-Tethys Ocean and its dynamic mechanism. Basalt samples from the Luobadui Formation in the Leqingla area, NW of Linzhou City in the central Lhasa subterrane, southern Tibet exhibit arc-like geochemical signatures in a subduction-zone tectonic setting characterized by high Al_(2)O_(3) and low TiO_(2) contents, fractionated REE patterns with low Nb/La ratios and high LREE concentrations, and negative hFSE anomalies. Based on their higher Th/Ce, Nb/Zr, and lower Ba/Th, Pb/Nd ratios, slightly negative to positive ε_(Nd)(t) values, and the relatively high Sr-Pb isotopic compositions, these samples were probably derived from partial melting of a depleted mantle source of garnet + spinel lherzolite, metasomatized by subducted sediments around 297 Ma. Modeling of the trace elements indicates that these basalts experienced fractional crystallization of olivine, clinopyroxene and minor plagioclase during magma ascent and eruption. It is proposed that these Late Carboniferous–Early Permian basalts are associated with the northward subduction of the Sumdo Paleo-Tethys Ocean seafloor along the southern margin of the central Lhasa subterrane.

关键词： geochemistry northward subduction Sumdo Paleo-Tethys Ocean Lhasa terrane Tibet

Postbiotics from Saccharomyces cerevisiae fermentation stabilize microbiota in rumen liquid digesta during grain-based subacute ruminal acidosis(SARA) in lactating dairy cows

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Journal of Animal Science and Biotechnology 2024年第5期15卷 2059-2080页

作者： Junfei Guo Zhengxiao Zhang Le Luo Guan Ilkyu Yoon jan C.Plaizier Ehsan Khafipour Department of Animal Science University of ManitobaWinnipegMB R3T 2N2Canada Present Address:College of Food and Biological Engineering Jimei UniversityXiamenFujian 361021China Department of Agriculture Food and Nutrition DepartmentUniversity of AlbertaEdmontonAB T6G 2R3Canada Faculty of Land and Food Systems University of British ColumbiaVancouverBC V6T 1Z4Canada Diamond V Cedar RapidsIA 52404United States Present Address:Cargill Animal Nutrition 15407 McGinty Road WestWayzataMN 55391USA

Background Subacute ruminal acidosis(SARA)is a common metabolic disorder of high yielding dairy cows,and it is associated with dysbiosis of the rumen and gut microbiome and host *** study evaluated the impact of two postbiotics from Saccharomyces cerevisiae fermentation products(SCFP)on rumen liquid associated microbiota of lactating dairy cows subjected to repeated grain-based SARA challenges.A total of 32 rumen cannulated cows were randomly assigned to 4 treatments from 4 weeks before until 12 weeks after *** groups included a Control diet or diets supplemented with postbiotics(SCFPa,14 g/d Original XPC;SCFPb-1X,19 g/d Nutri Tek;SCFPb-2X,38 g/d Nutri Tek,Diamond V,Cedar Rapids,IA,USA).Grain-based SARA challenges were conducted during week 5(SARA1)and week 8(SARA2)after parturition by replacing 20%DM of the base total mixed ration(TMR)with pellets containing 50%ground barley and 50%ground *** DNA from rumen liquid samples was subjected to V3–V416S r RNA gene amplicon *** of rumen microbiota were compared among treatments and SARA *** Both SARA challenges reduced the diversity and richness of rumen liquid microbiota,altered the overall composition(β-diversity),and its predicted functionality including carbohydrates and amino acids metabolic *** SARA challenges also reduced the number of significant associations among different taxa,number of hub taxa and their composition in the microbial co-occurrence *** with SCFP postbiotics,in particular SCFPb-2X,enhanced the robustness of the rumen *** SCFP supplemented cows had less fluctuation in relative abundances of community members when exposed to SARA *** SCFP supplementation promoted the populations of lactate utilizing and fibrolytic bacteria,including members of Ruminococcaceae and Lachnospiraceae,and also increased the numbers of hub taxa during non-SARA and SARA *** with S

关键词： Postbiotics Rumen microbiota Saccharomyces cerevisiae fermentation products SARA

Soil Contamination With Zoonotic Geohelminths: Emerging Risks in the Philippines

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Infectious Microbes & Diseases 2024年第1期6卷 1-4页

作者： jan Clyden B.Tenorio Department of Veterinary Paraclinical Sciences College of Veterinary MedicineUniversity of Southern MindanaoKabacanCotabatoPhilippines

Soil-transmitted helminth(STh)infections continue to be the most prevalent of the 20 neglected tropical diseases,affecting nearly a quarter of the world’s population and causing approximately 2.54 million disability-adjusted life years.1,2 Ascaris lumbricoides,Trichuris trichiuria,and multiple species of hookworms(ie,Ancylostoma duodenale,Necator americanus and Ancylostoma ceylanicum)are known to cause significant infections in *** 70%of the infections are reportedly occurring in Asia,where nearly a quarter of the population is infected with at least one SThspecies.3,4 Infections are particularly deleterious among school-and preschool-aged children,women of reproductive age and immunocompromised *** cognitive and motor development,stunting,malnutrition and other potentially life-long sequelae are the known adverse health effects of STh infections in children.5–7 hence,control and elimination efforts have been directed at addressing the prevalence and burden of infections among at-risk populations.

关键词： soil-transmitted helminths neglected tropical diseases veterinary public health

Enhanced diagnostic workup increases pathological findings in patients with acute ischaemic stroke:results of the prospective hEBRAS study

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Stroke & Vascular Neurology 2024年第2期9卷 145-152,I0414-I0425页

作者： Simon hellwig Thomas Krause jan F Scheitz Juliane herm Ulrike Grittner Nadja Jauert Jochen B Fiebach Mario Kasner Wolfram Doehner Matthias Endres Rolf Wachter Thomas Elgeti Christian h Nolte Karl Georg haeusler Department of Neurology with Experimental Neurology Charité-Universitätsmedizin Berlincorporate member of Freie Universität Berlin and Humboldt-Universität zu BerlinBerlinGermany Center for Stroke Research Berlin BerlinGermany Berlin Institute of health at Charité–Universitätsmedizin Berlin BIH Biomedical Innovation AcademyBerlinGermany Department of Neurology Jüdisches Krankenhaus BerlinBerlinGermany German Center for Cardiovascular Diseases(DZhK) Partner Site BerlinBerlinGermany Institute of Biometry and Clinical Epidemiology Charité-Universitätsmedizin BerlinBerlinGermany BIh Center for Regenerative Therapies(BCRT) Berlin Institute of Health at Charité–Universitätsmedizin BerlinBerlinGermany Department of Cardiology Charité-Universitätsmedizin BerlinBerlinGermany Department of Cardiology Campus Benjamin FranklinCharité-Universitätsmedizin BerlinBerlinGermany German Center for Neurodegenerative Diseases(DZNE) Partner Site BerlinBerlinGermany Department of Cardiology University Hospital LeipzigLeipzigGermany Department of Radiology Charité-Universitätsmedizin BerlinBerlinGermany Department of Neurology University Hospital WürzburgWürzburgGermany

Background Stroke aetiology remains cryptogenic in a relevant proportion of patients with acute ischaemic stroke(AIS).We assessed whether enhanced diagnostic workup after AIS yields a higher rate of prespecified pathological findings compared with routine diagnostic care *** hospitalised patients with AIS were prospectively enrolled in the investigator-initiated observational hEart and BRain Interfaces in Acute Ischaemic Stroke(hEBRAS)study at the Charité,Berlin,*** with AIS without known atrial fibrillation(AF)underwent cardiovascular MR imaging(CMR),MR-angiography of the aortic arch and prolonged holter-ECG monitoring on top of routine diagnostic *** Among 356 patients with AIS(mean age 66 years,37.6%female),enhanced workup yielded a higher rate of prespecified pathological findings compared with routine care(17.7%vs 5.3%;phanced diagnostic workup(38.5%vs 45.5%,phocardiography in 228(64.0%)*** was successfully performed in 292(82.0%)patients and revealed more often a prespecified pathological finding compared with routine echocardiography(16.1%vs 5.3%).Furthermore,study-related ECG monitoring(median duration 162 hours(IQR 98–210))detected AF in 16(4.5%)patients,while routine monitoring(median duration 51 hours(IQR 34–74))detected AF in seven(2.0%)*** Enhanced diagnostic workup revealed a higher rate of prespecified pathological findings in patients with AIS compared with routine diagnostic care and significantly reduced the proportion of patients with cryptogenic *** registration number NCT02142413.

关键词： routine patients prospective

Uplifting the complexity of analysis for probabilistic security of electricity supply assessments using artificial neural networks

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Energy and AI

Energy and AI 2024年第3期17卷 313-326页

作者： Justin Münch jan Priesmann Marius Reich Marius Tillmanns Aaron Praktiknjo Mario Adam University of Applied Sciences Duesseldorf Centre of Innovative Energy SystemsMuensterstr.15640476 DuesseldorfGermany RWTh Aachen University E.ON Energy Research CenterChair for Energy System Economics(FCN-ESE)Mathieustrasse 1052074 AachenGermany

The energy sector faces rapid decarbonisation and decision-makers demand reliable assessments of the security of electricity supply. For this, detailed simulation models with a high temporal and technological resolution are required. When confronted with increasing weather-dependent renewable energy generation, probabilistic simulation models have proven. The significant computational costs of calculating a scenario, however, limit the complexity of further analysis. Advances in code optimization as well as the use of computing clusters still lead to runtimes of up to eight hours per scenario. however ongoing research highlights that tailor-made approximations are potentially the key factor in further reducing computing time. Consequently, current research aims to provide a method for the rapid prediction of widely varying scenarios. In this work artificial neural networks (ANN) are trained and compared to approximate the system behavior of the probabilistic simulation model. To do so, information needs to be sampled from the probabilistic simulation in an efficient way. Because only a limited space in the whole design space of the 16 independent variables is of interest, a classification is developed. Finally it required only around 35 min to create the regression models, including sampling the design space, simulating the training data and training the ANNs. The resulting ANNs are able to predict all scenarios within the validity range of the regression model with a coefficient of determination of over 0.9998 for independent test data (1.051.200 data points). They need only a few milliseconds to predict one scenario, enabling in-depth analysis in a brief period of time.

关键词： Security of electricity supply Probabilistic simulation Metamodeling Artificial neural networks Regression

Quantum Chromodynamics on Lattice: Direct Minimization of QCD-QED-Action with New Results

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Journal of high Energy Physics, Gravitation and Cosmology 2024年第1期10卷 228-256页

作者： jan helm Department of Electrical Engineering Technical University Berlin Berlin Germany

This paper describes a new numerical QCD calculation method (direct minimization of QCD-QED-action) and its results for the first-generation (u, d) hadrons. here we start with the standard color-Lagrangian LQCD = LDirac + Lgluon, model the quarks qi as parameterized gaussians, and the gluons Agi as Ritz-Galerkin-series. We minimize the Lagrangian numerically with parameters par = (par (q), {αk}, par (Ag)) for first-generation hadrons (nucleons, pseudo-scalar mesons, vector mesons). The resulting parameters yield the correct masses and correct magnetic moments for the nucleons, the gluon-distribution and the quark-distribution with interesting insights into the hadron structure.

关键词： QCD QED QCD On-Lattice Color Lagrangian hadrons

Calculation of the Standard Model Parameters and Particles Based on a SU(4) Preon Model

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Journal of Modern Physics 2024年第1期15卷 64-124页

作者： jan helm Department of Electrical Engineering Technical University Berlin Germany

This paper describes an extension and a new foundation of the Standard Model of particle physics based on a SU(4)-force called hyper-color, and on preon subparticles. The hyper-color force is a generalization of the SU(2)-based weak interaction and the SU(1)-based right-chiral self-interaction, in which the W-and the Z-bosons are Yukawa residual-field-carriers of the hyper-color force, in the same sense as the pions are the residual-field-carriers of the color SU(3) interaction. Using the method of numerical minimization of the SU(4)-action based on this model, the masses and the inner structure of leptons, quarks and weak bosons are calculated: the mass results are very close to the experimental values. We calculate also precisely the value of the Cabibbo angle, so the mixing matrices of the Standard model, CKM matrix for quarks and PMNS matrix for neutrinos can also be calculated. In total, we reduce the 29 parameters of the Standard Model to a total of 7 parameters.

关键词： SU(4) Generalization of Weak Interaction Extension of Standard Model Numerical Minimization of Action hyper-Color Preon

Origin and Basic Mechanism of Life

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Open Journal of Biophysics 2024年第3期14卷 265-329页

作者： jan helm Department of Electrical Engineering Technical University Berlin Berlin Germany

This paper presents in a concise way the main characteristics of life from the physical point of view and the most successful theories of biogenesis, together with a mathematical formulation and simulation of proto-biogenesis. We present here a calculation method for biochemical reactions based on the available reaction data base, and using this method, we calculate precise scenarios for the first life cycle, and for the first stages of terrestrial biological evolution.

关键词： Proto-Life-Cycle Prebiotic Evolution PNA World Genetic Proto-Code LUCA