bluuebunny/crossref_metadata_2025 huggingface dataset:
Reactivity modulation experiments for nuclear data in CROCUS within a CEA-EPFL collaboration
Authors: Geslot Benoit , Lamirand Vincent , Jiang Yifeng , Leconte Pierre , Pakari Oskari , Godat Daniel , Braun Laurent , Frajtag Pavel , Pantera Laurent , Pautz Andreas
Published: November 2023

In nuclear research reactors, integral experiments are powerful tools to measure integral core parameters, such as the delayed neutron fraction. Within the scope of the point kinetic approximation, reactivity modulation experiments can be used for probing the reactor transfer function and then infer integral parameters of the core.

In this context, Commissariat à l’Energie Atomique et aux Energies Alternatives (CEA) and Ecole Polytechnique Fédérale de Lausanne (EPFL) have been collaborating for developing a probe device (PISTIL) and measurement setup adapted to the CROCUS zero power research reactor operated by EPFL (Lausanne, Switzerland).

Despite some mechanical limitations of PISTIL, its maximum reactivity worth was measured with a good precision and repeatability using different methods (8.82 ±0.07 pcm), and its value is found rather close to the simulated one using TRIPOLI-4 (9.4 ± 0.4 pcm with JEFF-3.3). Above 1 Hz, the shape of the used modulation is pseudo-sinusoidal, with only a few well defined harmonics of excitation. The strongest harmonic only was analyzed using standard signal processing algorithms such as the Fourier transform and the Bartlett estimator. Twelve data points were produced in the range 0.5 Hz to 200 Hz, with uncertainty ranging from 1 % to 15 %. The prompt decay constant was measured at 150 ± 3 rad/s. Below 1 Hz, stepwise modulations were used with pseudo-random time sequences, which allowed exciting at once a large number of frequencies. Around 150 data points were produced in this particularly interesting frequency domain, between 1.6 mHz and 0.75 Hz, thanks to the use of three distinctive sequences with different base frequencies and overlapping ranges. The amplitude and phase of the RTF were measured satisfactorily, with uncertainties below 1 % for the strongest harmonics. The shape of the RTF was found consistent with the predictions of both JEFF-3.3 and ENDF/B-VII.1 libraries.
Specially developed LR-0 reactor graphite environment for gen IV reactor support and cross-section measurement
Authors: Peltan Tomas , Vilimova Eva , Czakoj Tomas , Matej Zdenek , Mravec Filip , Cvachovec Frantisek , Simon Jan , Juricek Vlastimil , Kostal Michal
Published: November 2023

This paper is focused on the development of the experimental environment connected to reactor graphite. Regarding its very good neutronic and mechanical properties, graphite will be very important in some new reactor designs, such as high-temperature or molten salt SMR reactors. These new reactor concepts require a new experimental environment as support for further research. In the laboratories of the Research Centre Řež and at the LR-0 reactor, the new experimentally validated graphite environment was created. This large graphite insertion is the largest graphite mono-block, which is possible to assemble at the LR-0 reactor. Sets of experiments for measuring reaction rates of different activation detectors for neutron field mapping were performed. This approach was used for thermal and epithermal region descriptions. For the fast neutron spectrum evaluation, the stilbene scintillation detector was used. All parameters, such as criticality height of moderator level, neutron spectrum, and other parameters for all experiments, were performed using Monte Carlo neutronic codes Serpent and MCNP. The obtained results were finally compared to the measurement of neutron leakage spectra from the graphite cube and graphite cylinder. These specially developed graphite-shaped neutron fields, reactor insertions, and external cube and cylinder with Cf neutron source can be used in the future for validation of not only materials used in SMR reactors but for arbitrary cross-section verification.
Ten springs of experiments in CROCUS
Authors: Lamirand Vincent
Published: November 2023

Around a decade ago, a new team rebuilt experimental research at EPFL’s nuclear facilities, and in particular in the CROCUS nuclear reactor. After a broad investigation and open discussions with colleagues from the nuclear community, a number of experiments and research directions were selected. They range from reactor physics to nuclear data, with a focus on instrumentation. We present here the variety of experiments carried out and how instrumentation has been instrumental in these perspectives. Developments on branching or intrinsic reactor noise were made possible thanks to extensive theoretical investigation coupled with the developments of pulse and current modes neutron detection systems, as well as the LEAF gamma detection array. With regard to modulation or perturbation reactor noise, a study of fuel rods vibration was carried out thanks to the unique COLIBRI in-core fuel rods oscillation device; in the VOID experiments, a method was tested to measure the void coefficient with neutron modulation; in the APRHODITE project, the PISTIL rotating absorber, or absorber of variable strength, was used to determine the zero power reactor transfer function, in order to obtain feedback on kinetics nuclear data, particularly delayed neutrons. On the topic of nuclear data, the PETALE programme consisted on criticality and transmission experiments for the study of stainless steel, using instrumented metal reflectors. New dosimetry methodologies were developed for consistent and complete propagation of uncertainties, which also enabled experiments to be optimized. It will be continued in the HARVEST-X project, and its pile-oscillation program, BLOOM. Last but not least, developments in dosimetry as well as for a novel miniature neutron scintillation technology (MiMi detectors) allowed for interand intrapin (NECTAR) neutron measurements. 160 MiMi detectors have recently been distributed throughout the CROCUS core in a unique 3D detector array called SAFFRON, paving the way for novel high-resolution neutronics.
Characterization and performance of an acoustic sensor for fission gas release characterization devoted to JHR environment measurements
Authors: Baudry F. , Rosenkrantz E. , Combette P. , Fourmentel D. , Destouches C. , Bonzon P.V. , Paumel K. , Ferrandis J.Y.
Published: November 2023

For over a decade, the IES laboratory has been working in collaboration with the CEA on the development of acoustic instrumentation in the nuclear field. As part of this collaboration, the IES acoustics team is developing a miniaturized gas composition sensor for in situ measurements of gas composition in a fuel rod. The first experimental use of an acoustic sensor to measure gas composition dates back to 2010 with the REMORA 3 experiment, which estimated the release of fission gas in an experimental fuel rod. Unlike the sensor tested during REMORA 3, this new sensor should be able to operate at 300°C, a performance made possible by the use of a piezoelectric element based on bismuth titanate (NBT). The material is screen-printed onto an alumina substrate. The manufacturing process and initial characterization were presented in the previous version of ANIMMA 2021 [1].

In this article, we will focus on the performance of this type of sensor by characterizing different gas mixtures representative of the gases inside a fuel rod, in order to estimate relative deviations under laboratory conditions.
Towards the enhancement of nuclear reactor safety: Physical phenomena involved in the measurement accuracy of boron concentration online monitoring systems
Authors: Tabti Nouhaila , Sari Adrien , Tromson Dominique
Published: November 2023

In Pressurized Water Reactors (PWRs), boron10 (10B) is added to the primary fluid as boric acid to regulate criticality and power distribution within the core. Indeed, 10B possesses a significant neutron absorption cross-section of approximately 3845 barns for thermal neutron energy (around 25.3 meV). Thus, under certain circumstances, even a slight variation in boron concentration could lead to criticality issues. This paper addresses the problems regarding the accuracy and real-time measurement of Boron Concentration Online Monitoring Systems (BCOMS) in PWRs. First, the paper focuses on presenting BCOMS’s key performance and qualification criteria to ensure a real-time, accurate response during normal operation, operational transients, and accidental events. Then, we evaluate the influence of different dimensioning parameters on the overall measuring performance through Monte Carlo simulations using the MCNP6.2 code. Finally, we investigate, combining theoretical knowledge and simulation results, the physical phenomena involved in the measurement accuracy of BCOMS. This analytical approach not only fosters a deeper comprehension of the underlying phenomena but also facilitates the identification of potential areas for improving measurement accuracy, thereby enhancing the safety of nuclear reactors.
An Extended List-Mode MLEM Algorithm for 3D Compton Image Reconstruction from Multi-View Data
Authors: Le Nhan , Snoussi Hichem , Hmissi Zied , Iltis Alain , Lebonvallet Guillaume , Zeufack Ghislain
Published: November 2023

The lack of parallax in the measurements is a big challenge in 3D image reconstruction for handheld Compton cameras. Our solution to this issue is to extend the conventional list-mode maximum-likelihood expectation-maximization (LM-MLEM) 3D reconstruction algorithm to allow the simultaneous use of multi-view Compton data seeking parallax improvement. It involves building a new list-mode simultaneous data space from multi-view Compton events, formulating the associated probabilistic models for the system response matrix and sensitivity, and developing an extended LM-MLEM algorithm. For the performance assessment, we experiment the extended 3D reconstruction algorithm on real multi-view data conducted with a handheld CeBr3 Compton camera developed by Damavan Imaging and a punctual 0.2 (MBq)22Na source. Various comparative studies with different view numbers, source locations and energy ranges confirm the outperformances of our extended LM-MLEM algorithm.
Seeing radioactivity: Gamma-ray imaging technique applied to TRIGA RC-1 Research Reactor in ENEA Casaccia
Authors: Gagliardi Filippo , Ciotoli Alessandro , Gorello Edoardo , Meschini Luigi , Pagliuca Marco , Mauro Egidio , Cherubini Nadia , Lepore Luigi , Gandolfo Giada , Marzo Giuseppe A. , Falconi Luca , Formenton Davide , Roberti Andrea
Published: November 2023

Current radiological characterization protocols applied in nuclear installations provide a valuable set of information used to assess level and distribution of radioactivity, which is a crucial information in the plant management. Nevertheless, typical routines may present limitations that novel technologies can alleviate. In this work, a new-generation 3D pixelated CdZnTe gamma imaging and spectrometer detector has been used at TRIGA RC-1 Research Reactor in ENEA Casaccia Research Centre to assess its performances in several possible tasks and effectively understand this technology readiness. In particular, three possible tasks have been considered: survey of potentially contaminated area (with determination of known and unknown hot spots), source identification and localization (including neutron sources via their gamma emissions), and quantification of isotope-specific activities in generic components thanks to the point-kernel-based algorithm the system is equipped with. The experience has demonstrated the capability to achieve reliable results in these tasks, with consequences that could impact not only the current characterization protocols but also the way some Nuclear Safeguards and Non-Proliferation operations are performed.
A new technique for quick identification of defective region inside γ-ray detector
Authors: Das Biswajit , Palit R. , Kundu A. , Dey P. , Malik V. , Jadav S.K. , Naidu B.S. , Vazhappilly A.T.
Published: November 2023

The γ-ray detection efficiency of a detector decreases over time due to factors like radiation damage or an increase in the thickness of the inactive dead layer. For large γ-ray detector facilities, it is crucial to assess the health condition and performance of the inner regions of the detector crystals over time. In this study, we have introduced a method using GEANT4 simulation to detect defective regions within thick γ-ray detectors. In the experimental phase, a scanning setup was employed, comprising a single-crystal High Purity Germanium (HPGe) detector and a position-sensitive GAGG:Ce detector for coincidence measurements, using a 22Na source. The 2D images were reconstructed from the front-face and side-face scans of the single-crystal coaxial HPGe detector, employing an energy gate set at 511 keV. A position gate applied to a specific section of those 2D images allowed for the mapping of γ-ray interactions along a conical path within the HPGe detector. The methodology involved the comparison and analysis of histograms generated from various sector gates, facilitating the identification of the defective region’s position. In the GEANT4 simulation, a defective region was defined within the crystal, and that was effectively represented in the corresponding scanned image, which exhibited reduced efficiency. It’s important to note that this method’s effectiveness is restricted by the absorption profile of the 511 keV γ-ray, limiting its applicability to a depth of approximately 4 cm from the surface of the HPGe crystal. However, this approach can offer a swift and convenient method for inspecting γ-ray detectors, making it a valuable tool for the detector industry.
Methodology for an experimental drift velocity determination using a μTPC. Example in a 700mbar 95%He+5%CO2 mixture
Authors: Vinchon Thibaut , Petit Michaël
Published: November 2023

The micro-irradiation, neutron metrology and dosimetry laboratory of the Institute for Radiological Protection and Nuclear Safety (IRSN) is a National Metrological Institute associated laboratory, is in charge of the neutron fluence distribution references and produces neutron reference fields.

The laboratory is developing a primary neutron-detector based on the use of Time Projection Chamber technology. This detector, called µTPC, can use different types of gas over a range of precise pressures. The analysis of μTPC data requires the determination of both the energy and the track direction of the recoil particles. The drift velocity in the gas is a key data point for analysis. Based on several experimental measurements performed using the µTPC with monoenergetic neutron fields, a direct methodology to determine the drift velocity can be proposed. These results are compared with those found using theoretical drift velocity from the Magboltz simulation.
Warum wir einen psychologisch informierten Ansatz in der Rehabilitation von VKB-Verletzungen brauchen!
Authors: Diemer Frank , Zebisch Jochen
Published: November 2023

Nachdem sich bei der Rehabilitation von Rückenpatienten zunehmend die Erkenntnis durchgesetzt hat, dass auch psychologische und verhaltensbezogene Faktoren
Beachtung finden müssen, um ein gutes Ergebnis zu erzielen, verbreitet sich der biopsychosoziale Ansatz immer mehr in der Rehabilitation von
Sportverletzungen. Auch nach Kreuzbandverletzungen hängt ein gutes funktionelles Ergebnis und die Fähigkeit, wieder in den Sport zurückkehren zu können,
nicht nur von biologischen Faktoren wie Kraft, Mobilität und mechanischer Stabilität ab.
Ergebnisse der endoskopischen Vorsorge und Therapie des Duodenums bei MUTYH-assoziierter Polyposis
Authors: Haas Sonja , Strassburg Christian P. , Nattermann Jacob , Hueneburg Robert
Published: November 2023

Die MUTYH-assoziierte Polyposis (MAP) ist ein sehr seltenes autosomal-rezessiv vererbtes Polyposissyndrom. Ursächlich ist eine homozygote oder Compound-heterozygote Keimbahnmutation im MUTYH-Gen. Die MAP ist durch zahlreiche kolorektale Adenome charakterisiert, weiterhin liegt ein erhöhtes Risiko für kolorektale Karzinome (KRK) vor. Jedoch kann der Phänotyp sehr variabel sein, bspw. haben Betroffene auch ein erhöhtes Risiko für Polypen des oberen Gastrointestinaltraktes und für die Entwicklung von Duodenalkarzinomen.

In diese Studie wurden 15 Patienten mit Nachweis einer pathogenen MUTYH-Variante eingeschlossen, die am Nationalen Zentrum für erbliche Tumorsyndrome untersucht wurden. Die Ergebnisse der Ösophagogastroduodenoskopien (ÖGD) wurden in einer Datenbank prospektiv erfasst in einem Zeitraum vom Jahr 2012 bis zum Jahr 2023.

Mindestens 1 ÖGD (Median 4, Spannweite 1–15) erfolgte bei 15 Patienten, von denen 7 eine homozygote und 8 eine Compound-heterozygote pathogene MUTYH-Variante tragen. Der Überwachungszeitraum lag im Median bei 115 Monaten (Spannweite 3–215 Monate). Das mediane Alter zur Erstuntersuchung lag bei 44 (Spannweite 17–65) Jahren. Insgesamt erfolgten 72 ÖGDs (Median 4; Spannweite 1–15). Bei 5 Patienten zeigten sich duodenale Adenome, histologisch zeigten sich in all diesen Fällen tubuläre Adenome mit leichtgradiger intraepithelialer Dysplasie (LGIEN). Die Anzahl der insgesamt detektierten Duodenaladenome lag bei 48, die mediane Anzahl betrug 3 (Spannweite 1–37). Im Überwachungszeitraum wurde weder eine hochgradige intraepitheliale Neoplasie (HGIEN) noch ein Duodenalkarzinom detektiert.

Patienten mit einer MUTYH-assoziierten Polyposis sollten in einem interdisziplinären Zentrum für erbliche Tumorerkrankungen betreut werden. In unserer Kohorte zeigten sich mehr Patienten mit Duodenaladenomen im Vergleich zu bisher publizierten Daten. Allerdings konnte durch die erfolgte endoskopische Therapie keine Progression zu HGIEN oder Duodenalkarzinomen beobachtet werden.
Reduzierte Amputationsrate bei Patienten mit diabetischem Fußsyndrom seit Einführung eines minimalinvasiven Konzepts
Authors: Algharib Ahmed , Koning Giel G. , van Dortmont Lourina M.C. , Riedel Sandra , Möller Rüdiger
Published: November 2023

Amputationen sind immer „die letzte Option“ für Patienten mit Gefäßerkrankungen. In Deutschland leiden derzeit mehr als 4,5 Mio. Patienten an Diabetes mellitus. Seit wir das minimalinvasive Konzept zur Behandlung des diabetischen Fußsyndroms eingeführt haben, stellen wir nach kritischer Bewertung einen abnehmenden Trend bei der Rate von kleinen und großen Amputationen fest.

Ethik und informierte Einwilligung waren bei dieser retrospektiven Auswertung gewährleistet. Jährlich wurden etwa 150 Patienten mit komplexem diabetischem Fußsyndrom behandelt. Seit Juli 2021 behandeln wir unsere Patienten mit einem minimalinvasiven Konzept als eine von vielen multidisziplinären Modalitäten. Zur Auswertung wurden unsere diabetischen Patienten einbezogen, die in den definierten Zeiträumen von 2018 bis 2023 (einschl. Revisionsamputationen) kleine und große Amputationen durchliefen, und sie wurden analysiert. Wir verglichen die letzten 30 Monate (Gruppe 2) seit Einführung dieses Konzepts mit den letzten 30 Monaten zuvor (Gruppe 1).

Insgesamt stellten sich von 2018 bis 2023 810 Patienten mit irgendeiner Form des diabetischen Fußsyndroms in unserer Klinik vor, von denen 242 Patienten eine primäre chirurgische Behandlung benötigten. Patienten in Gruppe 1 zeigten eine Rate von 4% für große Amputationen, eine Rate von 13% für kleine Amputationen und eine Gesamtrate für Revisionsoperationen von 4%. Patienten in Gruppe 2 zeigten eine Rate von 2% für große Amputationen, eine Rate von 10% für kleine Amputationen und eine Gesamtrate für Revisionsoperationen von 2%.

Nach Einführung des minimalinvasiven Konzepts als Anpassung an unseren multidisziplinären Ansatz zur Behandlung von Patienten mit diabetischem Fußsyndrom stellen wir in unserer kritischen Bewertung einen abnehmenden Trend sowohl bei der Rate von kleinen als auch bei großen Amputationen fest. Obwohl weitere Forschung erforderlich ist, um unsere Ergebnisse zu bestätigen oder abzulehnen, kann die Implementierung minimalinvasiver Chirurgie in das Armamentarium regionaler Krankenhäuser durchaus zu einem besseren Gesundheitszustand von Patienten beitragen.
Efficient and Scalable Synthesis of 6,6-Dimethyl-3-oxabicyclo [3.1.0]hexan-2-one through Organocatalyzed Desymmetrization and Chemoselective Reduction
Authors: Echeverria Pierre-Georges , Tintori Guillaume , Jacob Clément , Delsarte Christine , Potié François , Grimaud Laurence , Vitale Maxime
Published: November 2023

The development of a robust process to 6,6-dimethyl-3-oxabicyclo[3.1.0]hexan-2-one, a key intermediate toward several active compounds of interest, is described. A scalable organocatalyzed desymmetrization was first studied and the reaction proved to be compatible with standard dilution. A kinetic study was performed to elucidate substrate and catalyst concentration dependences. Next, a chemoselective reduction of the carboxylic acid was developed. The scalability was demonstrated on 100 g scale through a fully telescoped process.
Rh(III)-Catalyzed Synthesis of Isocoumarins via C–H Activation of Phenacyl Phosphoniums with Iodonium Ylides
Authors: Yao Jinzhong , Miao Maozhong , Zhou Hongwei , Jiang Lu , Gao Lei , Li Xiaofei , Shao Tingting
Published: November 2023

A phosphonium-assisted C–H cyclization with iodonium ylides has been developed under redox-neutral rhodium(III) catalysis, offering a wide variety of valuable isocoumarins in moderate to good yields. This transformation proceeds through C–H activation, carbene insertion, and nucleophilic addition processes. The reaction occurs under a low catalyst loading in a short reaction time and does not require an oxidant.
Compressive Strength of Newly Developed Nonsintered Hydroxyapatite Blocks for Bone Graft Applications
Authors: Sunarso Sunarso , Suryadi Abdi , Indrani Decky Joesiana , Pangesty Azizah Intan
Published: November 2023

Objective This study aimed to fabricate and evaluate the phase purity and compressive strength of the nonsintered hydroxyapatite (HA) block obtained via phase transformation of set calcium sulfate dihydrate (CSD) block under hydrothermal conditions at different temperatures.

Materials and Methods Nonsintered HA block was prepared by immersion CSD block (4 mm in diameter and 8 mm in height) in a 1 mol/L sodium phosphate (Na3PO4) solution under hydrothermal conditions at 100°C, 140°C, and 180°C for 48 hours. X-ray diffraction was used to determine the crystalline phase of the obtained blocks. The mechanical strength of the blocks was measured using a compressive strength test.

Results The result shows that the CSD block could be fully transformed into a HA block at 180°C for 48 hours without changing its macroscopic shape. The compressive strength of the obtained blocks was lower compared with the CSD block.

Conclusion The current method has successfully produced a nonsintered HA block at 180°C for 48 hours. The compressive strength of the HA block decreased compared with the gypsum block used as a precursor. However, the compressive strength of the HA block that was produced still falls within the range of cancellous bone.
Influence of Wearing a Tactical Harness on Three-Dimensional Thoracic Limb Kinematics
Authors: Sandberg Gabriella S. , Pawloski Thomas , Kang Sean , Banu Eliza , Torres Bryan T. , Budsberg Steven C.
Published: November 2023

Objective The aim of this study was to assess the impact of a tactical harness on three-dimensional motion of the thoracic limb in dogs.

Animals Five adult mixed-breed dogs (age: 4–6 years, weight: 25–35 kg) were used in this study.

Methods Custom-fit tactical harnesses were applied to each dog and 19 retroreflective skin markers were used to determine three-dimensional joint motion during dynamic motion, with and without the harness. Sagittal plane (flexion–extension), transverse plane (internal–external rotation), and frontal plane (abduction–adduction) kinematics were created for the shoulder, elbow, and carpus from motion capture data, with and without the harness. Kinematic waveforms were analysed using statistical parametric mapping paired t-tests (a = 0.05). Angular displacements were determined, and total joint range of motion was compared using paired t-tests (a = 0.05).

Results Wearing a tactical harness increased sagittal angular displacement in the elbow but decreased it in the shoulder and carpus. Significant differences were found in the kinematic waveforms in almost all joints at both a walk and trot. Dogs wearing the tactical harness had reduced flexion and increased abduction of the shoulder joint at a walk. The elbow joint had increased extension, reduced external rotation and increased abduction at both walk and trot. The carpus had reduced flexion at a trot and walk, as well as increased internal rotation and abduction at a walk.

Conclusion Wearing a tactical harness affected kinematic gait data of all joints of the forelimb. The elbow was affected in all three planes at both a walk and trot, while the shoulder joint was only affected at a walk when wearing a tactical harness.

Clinical Relevance The clinical impact of wearing a tactical harness is unknown at this time, particularly when dogs are performing their duties while wearing harnesses.
MNE–civil society interactions: a systematic review and research agenda
Authors: Bruijn Kayleigh , Georgallis Panikos , Albino-Pimentel João , Kourula Arno , Teegen Hildy
Published: November 2023

Multinational enterprises (MNEs) and civil society (CS) interact in many ways across countries, with significant implications for these actors and for broader society. We review 166 studies of MNE–CS interactions in international business, general management, business and society, political science, sociology, and specialized non-profit journals over three decades. We synthesize this large and fragmented literature to characterize the nature (cooperation or conflict) and context (geography, industry, and issue) of MNE–CS interactions and uncover their antecedents, outcomes, and moderators. Our review reveals important blind spots in our understanding of the antecedents and outcomes of MNE–CS interactions and uncovers substantial discrepancy between the contexts of real-world MNE–CS interactions and the contexts examined in the literature. We propose actionable recommendations to (i) better indicate and expand the contexts where MNE–CS interactions are studied; (ii) enrich understanding of the antecedents of MNE–CS interactions by leveraging institutional and cultural perspectives; (iii) reorient research on the outcomes of MNE–CS interactions by examining the temporal dynamics of MNE learning and legitimacy, and (iv) emphasize societal relevance as reflected, for example, in green capabilities and moral markets. We hope this review will inspire new inter-disciplinary perspectives on MNE–CS interactions and inform research addressing urgent societal challenges.
Long-term effects of olive mill waste waters spreading on the soil rhizospheric properties of olive trees grown under Mediterranean arid climate
Authors: Abdennbi Siwar , Chaieb Mohamed , Mekki Ali
Published: November 2023

Context The spreading of olive mill waste waters (OMWW) could offer an appropriate management option to add value to this agricultural by-product, such as to increase soil fertility and plant productivity. Aims The main objective of this work was to evaluate the effects of the application of OMWW (at a fixed dose of 50 m3 ha−1), in the long term (20 years) on the soil rhizospheric properties and on old olive trees (80 years old) growth and productivity. Methods The experimental site consists of four plots treated with OMWW (T1, T2, T3 and T4) and four ‘control’ plots (C1, C2, C3 and C4), without any treatment. The treated plots have received each a fixed dose of 50 m3 ha−1 of OMWW in February of each year since 2004. Key results The results obtained showed that the addition of OMWW increased the soil water retention capacity (SWRC) and its organic matter content (OMC), as well as the augment of phosphorus (P) and potassium (K) levels. The activity of the soil rhizospheric microflora was significantly enhanced. Conclusions OMWW application to the soil surface in an olive orchard at 50 m3 ha−1, since 2004, had no negative effects on the tree’s vegetative growth and satisfied plant P, K and N requirement. Implications Our study showed that OMWW can enhance the soil properties and enrich the soil with necessary minerals.
“Ih gebiude dir, wurm!”
Authors: Concu Valentina
Published: November 2023

The number of diachronic studies on English speech acts has recently increased remarkably, highlighting the importance of these phenomena for the understanding of the contextualised dimension of linguistic interactions. Recent studies on the realisation of directives in Old English have shown how, in the Anglo-Saxon world, negative politeness did not play a significant role. This study also focusses on the realisation of directives from a diachronic perspective but concentrating on Old Saxon and Old High German, filling an empirical gap in the literature. Focussing on four manifestations, the preliminary data shows the Old Saxon and Old High German may have also been worlds “beyond politeness”.
Final report on APMP.EM-K2 key comparison of resistance standards at 10 MΩ and 1 GΩ
Authors: Yu Kwang Min , Kim Wan Seop
Published: November 2023

Main text

In order to link the National Metrology Institutes (NMI) organized in Asia Pacific Metrology Programme (APMP) to the key comparison CCEM-K2, APMP.EM-K2 key comparison was piloted by the Korea Research Institute of Standards and Science (KRISS), beginning in July 2010 and completed July 2014 with the participation of 13 National Metrology Institutes (NMIs). The results of this key comparison for 10 MΩ and 1 GΩ standards indicate good agreement among the 13 participating NMIs despite the long comparison period. Agreement is well within the level of confidence of 95%.

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.

The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Plasma catalysis: separating plasma and surface contributions for an Ar/N2/O2 atmospheric discharge interacting with a Pt catalyst
Authors: Hinshelwood Michael , Oehrlein Gottlieb S
Published: November 2023

Atmospheric pressure non-equilibrium plasmas can form nitrogen oxide (NO
x
) compounds directly from nitrogen and oxygen without a catalyst, and at lower catalyst temperatures than would be possible without plasma. In this work, the oxidation of plasma-produced NO from an Ar/N2/O2 non-equilibrium atmospheric-pressure plasma-jet (APPJ) over a platinum-on-alumina powder catalyst was investigated with in-situ infrared spectroscopy. Products downstream of the catalyst bed were analyzed along with catalyst surface species. The catalyst was exposed to plasma at both constant temperature and a cyclic temperature ramp in order to study long-lasting and transient surface changes. Primary incident reactive species to the catalyst were assessed to be NO and O3. Pt-Al2O3 at 350 °C increased oxidation of NO relative to Al2O3 or an empty chamber. The surface state of Pt-Al2O3 evolves during plasma-effluent exposure and requires upwards of 20 min exposure for stabilization compared to Al2O3. Once stable surface conditions are achieved, thermal cycling reveals a repeatable hysteresis pattern in downstream products. At low temperature, oxygen and NO
x
accumulate on the catalyst surface and react at elevated temperatures to form NO2. Increasing plasma power and O2:N2 ratio increases the hysteresis of the heating relative to the cooling curves in the pattern of NO2 formation. The limitation on NO oxidation at high temperatures was assessed to be Pt-O which is depleted as the catalyst is heated. Once stored species have been depleted, NO oxidation rates are determined by incoming reactants. Two overlapping NO oxidation patterns are identified, one determined by surface reactants formed at low temperature, and the other by reactants arriving at the surface at high temperature. The plasma is responsible for providing the reactants to the catalyst surface, while the catalyst enables reaction at high temperature or storage at low temperature for subsequent reaction.
What determines the rest frame of bubble nucleation?
Authors: Chen Yilin , Vilenkin Alexander
Published: November 2023

We revisit the question addressed in recent papers by Garriga et al.: what determines the rest frame of pair nucleation in a constant electric field? The conclusion reached in these papers is that pairs are observed to nucleate at rest in the rest frame of the detector which is used to detect the pairs. A similar conclusion should apply to bubble nucleation in a false vacuum. This conclusion however is subject to doubt due to the unphysical nature of the model of a constant eternal electric field that was used by Garriga et al. The number density of pairs in such a field would be infinite at any finite time. Here we address the same question in a more realistic model where the electric field is turned on at a finite time t
0 in the past. The process of turning on the field breaks the Lorentz invariance of the model and could in principle influence the frame of pair nucleation. We find however that the conclusion of Garriga et al. still holds in the limit t
0 → -∞. This shows that the setup process of the electric field does not have a lasting effect on the observed rest frame of pair nucleation. On the other hand, the electric current and charge density due to the pairs are determined by the way in which the electric field was turned on.
Fractal dynamics and computational analysis of local fractional Poisson equations arising in electrostatics
Authors: Singh Jagdev , Jassim Hassan Kamil , Kumar Devendra , Dubey Ved Prakash
Published: November 2023

In this paper, the local fractional natural decomposition method (LFNDM) is used for solving a local fractional Poisson equation. The local fractional Poisson equation plays a significant role in the study of a potential field due to a fixed electric charge or mass density distribution. Numerical examples with computer simulations are presented in this paper. The obtained results show that LFNDM is effective and convenient for application.
Optimum design and research of switched reluctance motor for electric vehicle based on Motor-Cad
Authors: Xu J Q , Liu Z S
Published: November 2023

With the development of the economy and the deepening of the energy crisis, electric vehicle has now become the hotspot of the global automotive industry. Therefore, as the key part of electric vehicle, the design and research of drive motor has become the focus of attention of engineers and technicians. Because of its simple structure, easy maintenance, high output power, high output torque, wide speed range, and high efficiency, the switched reluctance motor (SRM) has been one of the first choice of electric vehicle driving motors. According to the performance requirements of electric vehicle driving motors, a 3-phase 24/16 pole with rated power of 30 kW switched reluctance motor (SRM) for electric vehicle has been designed in this paper by using Motor-Cad which can be used to optimize the parameters of motor to make the overall structure of the motor more reasonable. In order to reduce the torque ripple of switched reluctance motor, appropriate stator polar arc and rotor polar arc design are used in the motor. To realize the speed control of switched reluctance motor in a wide range, PWM control mode is adopted in this paper, which has fast motor response speed, high power factor and excellent dynamic and static performance. The simulation results show that the performance indexes of the switched reluctance motor meet the design requirements completely.
Preliminary study on friction stir spot welding of plastic sheets with non-metallic tools
Authors: Liu C T , Xu S H , Shen H G , Chang Y P
Published: November 2023

In recent years, 3D printing technology of engineering plastics is often used in various fields to develop prototypes of parts. Friction stir spot welding of lap joints of different engineering plastics has considerable potential for industrial applications. This study used a self-developed non-metallic tool to successfully form the PLA joints on a modified conventional drilling machine. The results show the average downward force and average welding torque decreased with increasing the rotating speeds and dwell times. The stir zone width is slightly increased with increasing the rotating speed, and its signification increased with the dwell time. The increase in stir zone width on the different rotating speeds and the dwell times is similar to the increasing trend in average temperature. The average temperature multiplied by the dwell time defined as the bonding factors is similar to the diffusion bonding. The stir zone width is increased with increasing the bonding factor because there has still some distance between the shoulder to the lap surface, the stir action by the shoulder is not easy riches to the lap surface, so the stir zone only occurs within the FSP zone and the stir zone width never exceeds the shoulder diameter.
Microstructure and mechanical properties of 316L stainless steel of selected laser sintering
Authors: Lin J , Ye Y T , Lin H Y , Wang P S , Wang C A , Tseng S C
Published: November 2023

In recent years, additive manufacturing (AM) has received global attention, because the AM can manufacture irregular and complex-shaped parts and reduce material waste. In this paper, the 316L stainless steel powder was made into a structure conforming to the size of ASTM E8 by the selected laser sintering (SLS). The AM parameters were set as fixed laser power (220 W) and layer thickness of 0.03 mm, as well as scanning speed (900 mm/s and 800 mm/s), different annealing temperatures (750°C, 850°C and 950°C), and time (3 minutes, 6 minutes and 9 minutes). The results show that the optimal tensile strength was 639 MPa when the scanning speed was 800 mm/s, and the annealing temperature and time were 750°C and 3 minutes, respectively. In addition, the maximum elongation was 43% when the annealing temperature and time were 850°C for 6 minutes and 9 minutes, and 950°C for 9 minutes. The as-SLS of fast and slow scanning speeds were compared, the maximum tensile strength increased from 575 MPa to 639 MPa (increased by 11.1%), and the elongation increased from 21% to 32% (increased by 13.1%). The significant records of the 316L mechanical properties are extremely important for the fundamental understanding of SLS.
Eosin-Y containing electrospun fibers for optical ammonia sensing based on wavelength shift
Authors: Simanjuntak M S , Chu C S , Rispandi R , Putro D
Published: November 2023

Sensors in recent days have been in great demand in industrial zones of simple, low-cost sensors for effectively sensing various gases. This research work develops electrospinning fibers for optical ammonia sensing based on the wavelength shift. The optical sensing fibers were produced approach by the electrospinning technique. The addition of cellulose acetate (CA) matrix with doped Eosin-Y is an NH3 fluorophore. The same light emitting diode (LED) light source was used to excite NH3-sensitive dyes at 380 nm peak wavelength. Display the eosin Y emission spectrum, with a maximum wavelength of 582 nanometers. The observed red emission wavelength shift and fluorescence intensity at 582 nm decreased with increasing concentrations of NH3. The emission spectrum of eosin-Y fluorescence at 582 nanometers is changed with increasing NH3 concentrations ranging from 0 to 500 parts per million. In this work, according to the experiment results, the sensitivity of NH3 sensors is 7.73. Finally, the electrospinning fibers for optical NH3 sensing developed as a result of this research enable effective sensing of NH3 concentrations in practical applications in a variety of fields, including medical and industrial.
FEM simulation optimization and slab method on rotating extrusion of thin-walled round tube under constant shear friction
Authors: Chang K H , Huang B C , Teng H Y , Tzou G Y
Published: November 2023

This research considering constant shear friction is to explore the rotating extrusion of thin-walled round tube based on FEM simulation and slab method, and compares the results of both models to realize the variations and acceptance. The effective stress, the effective strain, the velocity field, the average thickness, the extrusion force, and the extrusion torque can be obtained from this study. It reveals the average thickness obtained from rotating extrusion is more uniform than that obtained from no rotating extrusion. The FEM optimization for extrusion force can be combined with Taguchi method, the L934 orthogonal table considers the four control factors which are outer diameter to thickness ratio, frictional factor, rotating angular velocity, half die angle, and three levels. The ranking of influence factors and the optimization combination can be obtained from FEM simulation optimization. Eventually the extrusion force between FEM simulation and slab method is compared under rotating angular velocity, 0.2 rad/s, the maximum error is 10.49 % and the minimum error is -0.29%; the average error is 4.16%, so the trend is in good agreement each other. Therefore, the both models can be verified.
Effect of Hot Isostatic Pressing on Microstructure and Properties of GH4169 Superalloy Manufactured by SLM
Authors: Lv Zhoujin , Chen Shuo , Che Lida , Niu Shanting , Xin Hongpeng , He Jing , Li Xiangyang
Published: November 2023

During the additive manufacturing of the GH4169 superalloy, various defects including cracks and holes can occur in the alloy. In this study, the effects of distinct HIP temperatures and pressure on the microstructure and mechanical properties of GH4169 were studied utilizing the metallographic microscope(OM), scanning electron microscope(SEM), X-Ray diffraction(XRD), density, microhardness, and tensile experiment. SEM and XRD results indicate that HIP can alter the texture of the matrix phase and dramatically modify the microstructure of the test alloy manufactured by SLM. Following HIP, density increases due to the pore closure of GH4169, and the hardness decreases due to the decomposition of Laves phase. Tensile testing revealed that increasing HIP temperature and pressure led to a slight reduction in the tensile strength and yield strength of the test alloy, while elongation exhibited an opposite trend. Furthermore, the increase in elongation is attributed to the improvement of the microstructure uniformity of the test alloy by HIP. And the evidence suggested that 1165°C, 155MPa is an optimal HIP parameter. Besides, the resulting alloy has a high tensile strength (1046MPa), yield strength (654MPa), and elongation (42%). The Laves phase and carbide are evenly distributed. This optimal HIP parameter will facilitate subsequent heat treatment for obtaining higher mechanical properties of the alloy.
GH3536 superalloy prepared by selective laser melting: microstructure and properties
Authors: Zhang Y , Wang Y , Zhang B , Song M , Li Y , Li Y
Published: November 2023

In this paper, GH3536 superalloy was prepared by selective laser melting (SLM) using plasma rotating electrode powder as raw material. The effects of forming and heat treatment processes on the microstructure and mechanical properties of GH3536 superalloy were studied. The results show that there were obvious micro-cracks on the laser scanning plane of SLM samples, and the length of micro-cracks was between 10-100μm. The micro-cracks originated from the inside of the molten pools and penetrated the melting channels, and the heat treatment could not eliminate the cracks. With the increase of volume energy density (VED), the tensile strength and yield strength of SLM samples increased first and then decreased. The maximum values of tensile strength and yield strength reached 772.3MPa and 613.3MPa, respectively. However, with the increase of VED, the elongation of SLM samples decreased to 27.3%. After heat treatment, the tensile strength and yield strength of the material increased (up to 789MPa and 410MPa), but the elongation decreased.
Study on Hot Deformation Behavior and Microstructure Evolution of MgAlCuZnMnCe Alloy
Authors: Chunyu Ma , Nan Zhou , Tongyu Liu , Quan Dong , Chenghao Hou , Kaihong Zheng
Published: November 2023

The Mg79Al12.5Cu2.5Zn4MnCe multi-principal element alloys was prepared by induction melting under a high-purity argon. The true stress-strain curves at deformation temperatures of 250-350°C and strain rates of 0.001-1s−1 were used to establish the constitutive equations as well as the thermal processing map. The optimal hot processing parameters for the alloy were determined as a deformation temperature of 320-350°C and a strain rate of 0.1-1s−1. Further investigation into the impact of various deformation parameters on the microstructure and macrotexture of the alloy during hot compression was conducted. The findings indicate that at a deformation rate of 1s−1, the second phase of the alloy is broken and deformed. The texture intensity follows a pattern of initially decreasing and then increases as the temperature rises. The change in grain size is influenced by the deformation crushing effect, initiation of the non-substrate slip system, and grain growth. When the strain rate increases, the changes in texture intensity and distribution are not pronounced, indicating that the strain rate has minimal influence on the macro texture.
Preparation and characterization of Mg-P coatings on Mg-Zn-Y-Nd alloy for corrosion protection
Authors: Pan Y , Tan C , Han J , Liu G
Published: November 2023

To improve the corrosion resistance of Mg-Zn-Y-Nd alloy, Mg-P coatings were prepared on the surface by a simple chemical conversion method. The Mg-P coatings were optimized by regulating the reaction conditions such as the pH value of the conversion solution (4.2, 5, 6, and 7), treatment temperature (20 °C, 40 °C, and 80 °C), and treatment time (1 h, 2 h, and 3 h) in this study. Scanning electron microscopy (SEM) showed that the optimized Mg-P coating has a uniform surface structure. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) results demonstrated that the Mg-P coating consists of MgNH4PO4·6H2O and MgHPO4·3H2O. The cross-sectional morphology revealed that the Mg-P coating has a rough structure with a thickness of 8 μm. The effect of Mg-P coating on the corrosion resistance of Mg-Zn-Y-Nd alloy was investigated by in vitro immersion test, and it was found that the corrosion rate was effectively decelerated within 10 days. In summary, we studied the effects of reaction conditions for preparing Mg-P coatings on the surface of Mg-Zn-Y-Nd alloy by a chemical conversion method and effectively improving the corrosion resistance of Mg-Zn-Y-Nd alloy.
Effects of graphene and carbon nanotubes on mechanical enhancement and heat generation of rubber composites
Authors: Liu Y , Chen W D , Jiang D Z
Published: November 2023

Carbon nanofillers can enhance both thermal and mechanical properties of rubbers due to their high thermal conductivity and tensile strength at the nanoscale. But the effects of CNTs and GR on heat generation of rubber composites are yet unclear. In this paper, carbon nanotubes/carbon black/nature rubber (CNTs/CB/NR) composites and graphene/carbon black/nature rubber (GR/CB/NR) composites were prepared by using GR and CNTs as partial replacements for carbon black, respectively. The interfacial interactions between fillers and the rubber matrix were calculated by the contact angle test, the filler-matrix network was characterized by rubber processing analyzer, and the glass transition temperature of the composite was measured by dynamic mechanical analysis. Compared with CNT or CB, GR can be well wetted by NR and uniformly distributed in NR, so there was a strong interfacial interaction between them. The better interfacial interaction will promote the formation of a good network structure between the filler and the NR, and the network structure between the filler and NR further restricts the movement of rubber molecule chains. Therefore, the heat generation by the movement of the molecule chains is decreased, and the mechanical properties of the rubber composites are increased.