bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of liquefaction risk of sterile material in the inner dump of North Pesteana quarry in the conditions of flooding of the remaining gap
Authors: Apostu Izabela Maria , Lazar Maria , Faur Florin
Published: January 2020

In the conditions of the dump slopes formed by loose rocks, predominantly sandy rocks, which are at the first saturation, there is a significant risk of sliding due to liquefaction of the waste material. The liquefaction process may be triggered by hydrological, mechanical or seismic factors. In saturated sand, the space between the solid granules is completely filled with water, and the pore water pressure, which increases as the depth increases, causes the grains to move away from each other, so the material is flowing. Among the methods for assessing the liquefaction potential of rock masses/deposits can be summarized: historical phenomena observations, studying the liquefying potential area maps, analysis of geological process that led to the creation of rock deposits and the nature of rocks. The paper aims at assessing the risk of liquefaction of sterile material in the inner dump of the North Pesteana quarry during the flooding of the remaining gap, since the preliminary studies found that the sterile material consists of important fractions of sand, indicating that there is liquefaction potential. The risk of liquefaction was determined taking into account the liquefaction potential, the nature of the objectives in the area and the probability of liquefaction.
Analysis of thermal degradation behavior for some hydraulic oils, using FTIR-TGA coupling
Authors: Şuvar Niculina-Sonia , Prodan Maria , Nălboc Irina Vasilica , Szollosi-Moţa Andrei
Published: January 2020

The transitions between the vibrational energetic states of atoms represent the infrared absorption spectra, which is a band spectrum over which the transitions between energetic rotational states overlap.

One of the most important uses of infrared absorption spectrometry is the identification in quantitative terms of the structure of compounds from a substance, the analytes being either solid, liquid or vaporous.

The FTIR-TGA Coupling is a technique that permanently controls the mass loss in a sample, as a function of temperature and time, as well as the identification and recording of various compounds occurring during the combustion process.

Research on hydraulic oils has consisted of their analysis using the FTIR-TGA coupling in order to identify flammable substances that can generate explosive events.
Artificial arm for manipulations in toxic atmospheres based on EEG-EMG signals
Authors: Rosca Sebastian , Risteiu Marius , Leba Monica , Negru Nicoleta , Ridzi Mihai
Published: January 2020

Industrial environments with potentially toxic atmospheres such as research laboratories or test centers are at increased risk for human operator health, especially due to the very short time they need to act to prevent fatal events at work place. In this paper we propose a solution with industrial applicability based on human arm modelling and simulation that is capable of replacing human operator’s direct intervention in manipulating substances that can generate toxic vapors that affect air quality or contain substances with high epidemiological risk, or others that, in case of inappropriately manipulated, can produce potentially explosive situations. Based on an EEG-EMG solution, the human operator can control the human artificial arm remotely from a safety location only by using own electrical signals generated by the brain and the neurons network.
Locating the probable ignition source in fire expertise
Authors: Florea Gheorghe Daniel , Vlasin Nicolae Ioan
Published: January 2020

An important aspect in elucidating the causes of fire events occurence, is the identification of the initial outbreak following on-site investigations. Based on the information resulting from the event footprint (observed thermal and dynamic effects) in correlation with the results obtained in the laboratory tests on the collected samples, as well as the possible generating scenarios of the event, the most probable sources of ignition can be identified. The research team must thoroughly analyze all elements of thermal, mechanical, electrical, radiation, chemical, etc. which may have been present or incidents in the initial outbreak.

The computerized fire simulation software will also be used to verify possible scenarios with geometry modeling, combustible / flammable properties of the real case elements, as well as the location of the ignition source, following that the dynamics and propagation directions of simulated fire to be consistent with the case under consideration.
Pilot study on fields with high exposure to psychosocial risk factors
Authors: Iordache Raluca Maria , Petreanu Viorica , Mihăilă Delia Cristina
Published: January 2020

A pilot study concerning psychosocial risk factors that could determine work related stress and effects on work behaviour and health state was developed involving five fields of activity with high exposure on work related stress (education, health, transport, banking, financial consultancy). The study aimed to identify the main specific psychosocial risk factors in every of the five fields, in order to substantiate a method for assessing the risk factors for work related stress. The study used a complex ergonomic methodology, and one of the main instruments used to identify psychosocial factors was the Romanian version of The Copenhagen Psychosocial Questionnaire (COPSOQ).
Proposals on establishing a methodology for the systematic analysis of energy coal mixtures in judicial practice
Authors: Lorinţ Csaba , Traistă Eugen , Florea Adrian
Published: January 2020

There are several situations in which it is necessary to clarify the types of coal that enter into the composition of mixtures: technical expertise and/or establishing the nature of some coal wastes, often from old stockpiles, in order to eliminate them. The proposed method is based on the identification and description of those mineralogical-petrographic and physico-chemical properties whose pursuit can lead to a diagnosis in differentiation of coal types. Systematic analysis involves in the first stage the identification of the different types of coal present in the sample by mineralogical analysis. From the sample subjected to mineralogical analysis, granules are extracted from the different types of coal present in the sample and the characteristics defining them are determined: moisture and hygroscopic moisture content, volatile matter content, fixed carbon content, agglutination characteristics, etc. Further, the characteristics of the mixtures are determined on another part of the sample and their structure is determined by algebraic methods.
Research regarding the electrification risk of materials, technical equipment and appearance of electrostatic discharges in the presence of explosive atmospheres
Authors: Păun Florin Adrian , Părăian Mihaela , Popa Mihai Cătălin , Gabor Dan
Published: January 2020

The electrification process of the materials and technical equipment’s, especially the external parts of them, frequently occur during their use, being sometimes an intrinsic process, such as for example flowing of a flammable liquid through a pipe.

The electrification process of materials and technical equipment’s is responsible for generating, through specific mechanisms, significant quantities of electrostatic charges.

The presence of electrostatic charges on materials and technical equipment’s, used in areas with explosive atmospheres as a result of the electrification process can lead to electrostatic discharges occurrence, which in the presence of an explosive atmosphere may cause an explosion and/or fire.

The purpose of the paper is the analyze of essential safety and health requirements applicable to technical equipment’s and materials intended for use in areas with explosive atmospheres in order to identify and establish technical and organizational measures, by their application can eliminate the risk of electrification, the occurrence of electrostatic discharges and consequently the risk of an explosion and/or fire may be reduced.
Safety culture: a perpetual challenge or an opportunity for Romanian companies?
Authors: Moraru Roland Iosif , Băbuţ Gabriel Bujor , Cioca Lucian – Ionel , Popescu-Stelea Mihai , Vasilescu Victor-Gabriel
Published: January 2020

The main objective of the paper is to analyze the safety culture in order to understand how theory and practice can be integrated to improve safety performance and related economic outcomes. The research includes the synthesis of systematic studies on safety culture and the factors that influence the relationship between organizational culture and safety behavior. In a global manner, the results obtained generate relevant insights into how safety culture can be theoretically systematized and provide a series of recommendations that can guide the development of future safety culture interventions. Finally, a framework is proposed for an in-depth understanding of all the implications of safety culture in the practice of Romanian companies.
Study of potential wind power as a renewable energy source in the Motru area
Authors: Sultan Alin , Nan Marin Silviu , Ilioni Cristian , Vitan Cosmin , Mamara Nicoleta
Published: January 2020

The continuous development of the human society is in a close correlation with the increased consumption of electricity. In the past few years, the thirst for electricity at a global level, has led both to higher levels of pollution and the depletion of fossil fuels. For this reason, the issue of energy efficiency is a priority of energy strategy at national and EU level. In this context, a solution to the above problems is to increase the rate of production of electricity from renewable energy sources. Thus, the paper presents a study of wind energy as a source of renewable energy, their modelling and simulation for the Motru area.
The process of closing dynamics applied to the ventilation network of Paroşeni mine
Authors: Rădoi Florin , Cioclea Doru , Boantă Corneliu , Tomescu Cristian
Published: January 2020

The decision to begin the process of closing/preserving a mining objective requires the analysis of a complex of factors that interact and influence the efficiency of decision. Solving the ventilation networks with the help of computing is a huge step forward that allows optimization of the air management and real-time visualization of network changes. The method of solving the ventilation network with the help of the computation, allows the modeling and solving of the ventilation networks as well as any simulations of changes that may occur in the ventilation system regardless of its complexity, during the closing period. This paper will present the process of closing dynamics in a complex ventilation network.
Use of explosibility diagrams in potentially explosive atmospheres
Authors: Matei Adrian , Drăgoescu Răzvan , Ianc Nicolae , Chiuzan Emeric , Rădoi Florin
Published: January 2020

Although the first research in the field was carried out by Davy in 1816, the first discovery emerged in 1891 when Le Chatellier defined the law for determining the explosive limits. Lower Explosive Limit (LEL) represents the lowest concentration of gas or vapours in air which is able to generate the explosion in the presence of an efficient ignition source. It is considered to be the same as the Lower Flammability Limit (LFL). Upper Explosive Limit (UEL) represents the highest concentration of gas or vapours in air which is able to generate the explosion in the presence of an efficient ignition source. It is considered to be similar with the Upper Flammability Limit (UFL) [1]. For the optimal management of underground or surface industrial environments, confined, obstructed or open environments, is required to know the point which defines the monitored atmosphere in relation with the explosion triangle. For confined underground environments, monitoring the atmosphere and using the explosibility diagrams are required during the closure process and also for re-opening the area. For underground environments specific to active mine workings and for industrial environments located on the surface, monitoring the atmosphere and using explosibility diagrams are required permanently.
Phänomenologie des Schmerzerlebens von Patienten auf der Intensivstation
Authors: Ewerbeck Frederik
Published: January 2020

Schmerz ist ein weitverbreitetes Phänomen auf Intensivstationen. Die Erfassung dieses Phänomens ist herausfordernd, vor allem dann, wenn Betroffene nicht mehr selbstständig kommunizieren können. Es ist daher bedeutsam, wie häufig und zu welchen Anlässen Patienten auf Intensivstationen Schmerzen verspüren und ebenso, wie sie diese erleben. Dieser Artikel widmet sich diesem Erleben aus leibphänomenologischer Perspektive.
Burnout und Gratifikationskrisen im Längsschnitt bei
Ärztinnen und Ärzten während der fachärztlichen
Weiterbildung in Deutschland
Authors: Kocalevent Rüya Daniela , Pinnschmidt Hans , Nehls Sarah , Boczor Sigrid , Siegert Stephanie , Scherer Martin , Bussche Hendrik van den
Published: January 2020

Mehrere Studien belegen den hohen beruflichen Stress von Ärzten und
Ärztinnen bis hin zu Burnout-Symptomen. Untersucht In der vorliegenden
Studie wurde das Belastungserleben von Ärzten und Ärztinnen im
längsschnittlichen Verlauf der fachärztlichen Weiterbildung
untersucht. Dazu wurde der Frage nachgegangen, wie sich das Burnouterleben unter
Berücksichtigung von Gratifikationskrisen von Beginn bis zum Ende der
Weiterbildung an innerhalb von 6 Jahren verändert und ob es jeweils
einen Einfluss von Geschlecht und Elternstatus gibt. Die Datenerhebung erfolgte
im Rahmen der KarMed Studie. Eingesetzt wurden das Maslach Burnout Inventar
(MBI-HSS (MP)) und der Effort-Reward-Imbalance Fragebogen (ERI). Die
theoretischen Annahmen wurden in allgemeinen linearen Modellen und allgemeinen
linearen gemischten Modellen mit Meßwiederholungsdesign statistisch
überprüft. Es bestand ein hoher Zusammenhang zwischen dem
Ausgangsniveau der Belastung zu Beginn der Weiterbildung und dem
Belastungserleben zum Ende der Weiterbildung. Gratifikationskrisen hatten einen
signifikanten Einfluss auf die Sub-Skala emotionale Erschöpfung des MBI,
nicht aber auf die Subskalen persönliche Leistungsfähigkeit und
Depersonalisation. Signifikante Zeiteffekte fanden sich auf allen 3 Sub-Skalen
des MBI, mit signifikanten Geschlechtseffekten auf den Subskalen emotionale
Erschöpfung und Depersonalistaion. Der Elternstatus weist unter
Berücksichtigung der Burnout-Verlaufswerte und Gratifikationskrisen
keinen signifikanten Einfluss auf das Burnouterleben auf. Die theoretischen
Implikationen und die praktischen Konsequenzen für die
Gesundheitsförderung von ÄrztInnen werden ebenso diskutiert wie
die Begrenzungen der Untersuchung.
Copper-Catalyzed Synthesis of Alkyl-Substituted Pyrrolo[1,2-a]quinoxalines from 2-(1H-Pyrrol-1-yl)anilines and Alkylboronic Acids
Authors: Yan Rulong , Guan Xin
Published: January 2020

A radical pathway for the construction of pyrrolo[1,2-a]quinoxalines by using 2-(1H-pyrrol-1-yl)anilines and alkylboronic acids has been developed. Features of this process include Cu catalysis, readily accessible starting materials, and simple operations. Alkylboronic acids are used for the construction of pyrrolo[1,2-a]quinoxaline derivatives, and the desired products are obtained in moderate yields.
Synthesis of β-Lactams via Enantioselective Allylation of Anilines with Morita–Baylis–Hillman Carbonates
Authors: Zi You , Lange Markus , Schüler Philipp , Krieck Sven , Westerhausen Matthias , Vilotijevic Ivan
Published: January 2020

Enantioenriched β-lactams are accessed via enantioselective allylation of anilines with Morita–Baylis–Hillman carbonates followed by a base-promoted cyclization. The resulting 3-methyleneazetidin-2-ones are amenable to diastereoselective functionalization to produce analogues of biologically active β-lactams. The use of nearly equimolar quantities of the starting materials make this method efficient and straightforward.
Concise Synthesis of Potential 4-Hydroxy-5-fluoropentyl Side-Chain Metabolites of Four Synthetic Cannabinoids
Authors: Wallgren Jakob , Rexander Anders , Vestling Erik , Liu Huiling , Dahlén Johan , Konradsson Peter , Wu Xiongyu
Published: January 2020

Synthetic cannabinoids are a group of compounds that act on the CB1 receptor and are used illicitly as substitutes for cannabis. Given the rapid and extensive metabolism of synthetic cannabinoids, urinary biomarkers are essential if proof of drug intake is to be obtained in forensic laboratories. To identify good biomarker candidates, the metabolism of synthetic cannabinoids must be studied and reference standards need to be acquired. Studies on the metabolism of synthetic cannabinoids containing a terminally fluorinated pentyl side chain have shown that hydroxylation can occur at the four position of the side chain. This makes the 4-hydroxy-5-fluoropentyl side-chain metabolite a good urinary biomarker for proving intake of the corresponding parent drug, as this compound cannot be formed from its nonfluorinated analogue. Here, a concise synthetic route to the 4-hydroxy-5-fluoropentyl side-chain metabolites of the synthetic cannabinoids STS-135, MAM-2201, AM-2201, and XLR-11 is reported.
The Comparison of Intrathecal Ropivacaine with Bupivacaine for Knee Arthroscopy: A Meta-analysis of Randomized Controlled Trials
Authors: Xie Zhiwei , Nie Xiaoying , Xue Huiqin , Pan Linlin , Zhang Na
Published: January 2020

The comparison of intrathecal ropivacaine with bupivacaine for knee arthroscopy remains controversial. We conduct a systematic review and meta-analysis to explore the efficacy of intrathecal ropivacaine versus bupivacaine for knee arthroscopy. We search PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases through August 2019 for randomized controlled trials (RCTs) assessing the effect of intrathecal ropivacaine versus bupivacaine for knee arthroscopy. This meta-analysis is performed using the random effects model. Five RCTs are included in the meta-analysis. Overall, compared with intrathecal bupivacaine for knee arthroscopy, intrathecal ropivacaine is associated with increased onset time of motor block (mean difference [MD] = 2.05, 95% CI: 1.43–2.67, p < 0.00001) and decreased duration of sensory block (MD = −26.82, 95% CI: −31.96 to −21.67, p < 0.00001) but shows no remarkable influence on onset time of sensory block (MD = −0.09; 95% CI: −1.89 to 1.70, p = 0.92), duration of motor block (MD = −59.76; 95% CI: −124.44 to 4.91, p = 0.07), time to maximum block (MD = 2.35; 95% CI: –0.16 to 4.86, p = 0.07), first urination time (MD = −26.42, 95% CI: −57.34 to 4.51, p = 0.09), or first ambulation time (MD = 3.63, 95% CI: −25.20 to 32.47, p = 0.80).Intrathecal ropivacaine can substantially increase onset time of motor block and decrease the duration of sensory block than intrathecal bupivacaine for knee arthroscopy.
High Mach number limit of one-dimensional piston problem for non-isentropic compressible Euler equations: Polytropic gas
Authors: Qu Aifang , Yuan Hairong , Zhao Qin
Published: January 2020

We study the high Mach number limit of the one dimensional piston problem for the full compressible Euler equations of polytropic gas, for both cases that the piston rushes into or recedes from the uniform still gas, at a constant speed. There are two different situations, and one needs to consider measure solutions of the Euler equations to deal with the concentration of mass on the piston or formation of vacuum. We formulate the piston problem in the framework of Radon measure solutions and show its consistency by proving that the integral weak solutions of the piston problems converge weakly in the sense of measures to (singular) measure solutions of the limiting problems, as the Mach number of the piston increases to infinity.
A hybrid algorithm framework for small quantum computers with application to finding Hamiltonian cycles
Authors: Ge Yimin , Dunjko Vedran
Published: January 2020

Recent works have shown that quantum computers can polynomially speed up certain SAT-solving algorithms even when the number of available qubits is significantly smaller than the number of variables. Here, we generalize this approach. We present a framework for hybrid quantum-classical algorithms which utilize quantum computers significantly smaller than the problem size. Given an arbitrarily small ratio of the quantum computer to the instance size, we achieve polynomial speedups for classical divide-and-conquer algorithms, provided that certain criteria on the time- and space-efficiency are met. We demonstrate how this approach can be used to enhance Eppstein’s algorithm for the cubic Hamiltonian cycle problem and achieve a polynomial speedup for any ratio of the number of qubits to the size of the graph.
Boundary conditions for drift-diffusion equations in gas-discharge plasmas
Authors: Gorin V. V. , Kudryavtsev A. A. , Yao Jingfeng , Yuan Chengxun , Zhou Zhongxiang
Published: January 2020

This paper develops a general approach to the derivation of the boundary conditions for hydrodynamic equations for charged and neutral plasma components. It includes both a well-known classical case for pure diffusion and considers the expressions for diffusion and drift together—for an absorbing (neutralizing) wall with partial reflection and the possible emission of plasma components. Some unclear and controversial terms found in the existing literature are clarified. Several examples of applications of the results, which illustrate the properties of boundary conditions for electrons and ions, are calculated and analyzed.
Investigation of the spectral characteristics of silicon-vacancy centers in ultrananocrystalline diamond nanostructures and single crystalline diamond
Authors: Kunuku Srinivasu , Chen Yen-Chun , Chen Chien-Hsu , Kandasami Asokan , Chang Wen-Hao , Niu Huan , Leou Keh-Chyang , Lin I-Nan
Published: January 2020

Silicon-vacancy (SiV) centers were produced in single crystalline diamond (SCD) and ultrananocrystalline diamond (UNCD) nanostructures via Si ion implantation or in situ Si doping. SiV-embedded UNCD (SiV-UNCD) was fabricated by both top-down and bottom-up methods. The spectral properties of the SiV centers, including the zero phonon line (ZPL) width and decay time, were investigated in the SCD and UNCD nanostructures. All the SiV-UNCD nanostructures showed bright emission regardless of the preparation method. However, the decay time of the SiV centers was affected by the synthesis procedure. A SiV decay time of τ ∼ 0.19 ns was observed for UNCD nanostructures formed by in situ doping, whereas the SiV decay time was ∼0.43 ns for SiV-UNCD clusters prepared by Si ion implantation into UNCD deposited on Ti/sapphire substrates. The ultrasonication of UNCD clusters on Ti/sapphire pyramids produced bright SiV-UNCD nanoclusters with sizes of ∼50 nm, a ZPL width of 13.5 nm, and a decay time of 0.35 ns, suggesting promising potential in bioimaging applications. SiV-containing SCD (type Ia or type IIa) showed enhanced SiV spectral properties with a ZPL width of 6.08 nm and longer decay time of 1.3 ns.
Modeling of TAE mode excitation with an antenna in realistic X-point geometry
Authors: Dvornova A. , Huijsmans G. T. A. , Sharapov S. , Artola Such F. J. , Puglia P. , Hoelzl M. , Pamela S. , Fasoli A. , Testa D.
Published: January 2020

Experimentally, it is observed that Toroidal Alfvén Eigenmodes (TAEs) are difficult to excite with an external antenna when the plasma is in X-point geometry. Here, the effect of the X-point geometry on the efficiency of the TAE excitation with the external antenna is investigated. In the first part of this paper, the influence of the near-last closed flux surface layer from the core side on the damping of the TAE modes is calculated using the linear resistive eigenvalue MHD code CASTOR. The resistive damping is identified as the main cause of the TAE damping in the open gap in the Alfvén continuum. It is shown that one aspect of the difficulty of excitation of the TAE modes in X-point geometry is an increased damping from the region inside the separatrix. However, the increased damping with the plasma boundary approaching the separatrix is not general and depends on the density profile shape. The second part of this paper discusses the influence of the TAE behavior in the limiter and X-point geometries including the scrape-off layer (SOL) in the reduced MHD code JOREK. It is shown that the dominant effect on the damping of the original TAE mode observed in the limiter configuration is caused by the additional damping in the region of open field lines, i.e., the SOL.
Progress in narrowband high-power microwave sources
Authors: Zhang Jun , Zhang Dian , Fan Yuwei , He Juntao , Ge Xingjun , Zhang Xiaoping , Ju Jinchuan , Xun Tao
Published: January 2020

Even after 50 years of development, narrowband high-power microwave (HPM) source technologies remain the focus of much research due to intense interest in innovative applications of HPMs in fields such as directed energy, space propulsion, and high-power radar. A few decades ago, the main aim of investigations in this field was to enhance the output power of a single HPM source to tens or hundreds of gigawatts, but this goal has proven difficult due to physical limitations. Therefore, recent research into HPM sources has focused on five main targets: phase locking and power combination, high power efficiency, compact sources with a low or no external magnetic field, high pulse energy, and high-power millimeter-wave generation. Progress made in these aspects of narrowband HPM sources over the last decade is analyzed and summarized in this paper. There is no single type of HPM source capable of excellent performance in all five aspects. Specifically, high pulse energy cannot be achieved together with high power efficiency. The physical difficulties of high power generation in the millimeter wave band are discussed. Semiconductor-based HPM sources and metamaterial (MTM) vacuum electron devices (VEDs) are also commented on here. Semiconductor devices have the advantage of smart frequency agility, but they have low power density and high cost. MTM VEDs have the potential to be high power efficiency HPM sources in the low frequency band. Moreover, problems relating to narrowband HPM source lifetime and stability, which are the important determinants of the real-world applicability of these sources, are also discussed.
Effects of an external magnetic field on the hyperfine parameters in RE2O3 (RE = Gd, Er) nanoparticles measured by perturbed angular correlation spectroscopy
Authors: Correa E. L. , Bosch-Santos B. , Saxena R. N. , Cabrera-Pasca G. A. , Carbonari A. W.
Published: January 2020

In order to understand the interaction mechanisms in RE2O3 (RE=Gd, Er) nanoparticles (NPs), Perturbed Angular Correlation (PAC) spectroscopy, a local technique, plus external magnetic field, was used to elucidate local interactions and possible mapping of the different contribution in these compounds. NPs were synthesized by thermal decomposition and characterized by transmission electron microscopy and X-ray diffraction. PAC measurements were performed using 111In(111Cd) as probe nuclei, with and without the application of an external magnetic field (EMF) of 0.5 T in different temperatures (50 K, 100 K, 200 K, 300 K). Results show that the hyperfine magnetic field is almost zero when the probe is located at the symmetric site, and ∼4 T and ∼5 T for Gd2O3 and Er2O3, respectively, when the probe occupies the asymmetric field.
Impact of straightened thermal profiles generated by gapped near field transducers on HAMR SNR
Authors: Chow Cheng-Ming , Yin Mengxue , Qin Yuwei , Bain James A. , Zhu Jian-Gang (Jimmy)
Published: January 2020

In this work, heat assisted magnetic recording (HAMR) is simulated to assess the areal density advantages of various realistic thermal profiles. Specifically, finite element simulation and micromagnetic modeling are used to assess the areal density consequences of a straighter thermal profile with an associated wider track. This assessment is done by simulating the thermal profiles created by heads with gapped near field optical transducers (NFTs) and split magnetic poles. By varying the gap width of the NFT and the thickness of the medium interlayer, the above variation in transition straightness and associated written transition is achieved. At specific operating points, we find that a wider track with a straighter transition results in a slightly higher recording density (1.2Tb/in2 vs 0.9 Tb/in2). As expected, the former case finds its optimum at higher linear bit densities (1370 kFCI) and lower track densities (850 kTPI) than the latter case (870 kFCI and 1000 kTPI).
Computational analysis of ion orbital loss in diverted positive- and negative-triangularity tokamaks
Authors: Nishimura Y. , Waelbroeck F. L. , Zheng L. J.
Published: January 2020

The mechanism of ion orbital loss in diverted negative-triangularity (NT) tokamaks is significantly different from that of positive-triangularity (PT) tokamaks. The orbital loss from the edge of NT tokamaks can be quite large, because the separatrix X-point is located on the outboard side, meaning that trapped ions crossing the separatrix are lost to the inboard divertor plate after a mirror reflection on the side of the strong magnetic field. NT tokamaks have difficulties in building up steep pressure gradients in the edge regions. In contrast, the majority of trapped ions crossing the separatrix in PT tokamaks survive (through complete banana motions) without reaching the X-point region. For NT tokamaks, topological changes in the trapped ion trajectories can be achieved in the presence of the radial electric field, thus reducing the orbital loss, whereas for PT tokamaks, the orbital loss is relatively insensitive to the radial electric field.
Asymptotic solutions and convergence studies of the resistive inner region equations
Authors: Glasser A. H. , Wang Z. R.
Published: January 2020

A recent publication presents a detailed prescription for constructing global eigenfunctions and complex growth rates for resistive instabilities in axisymmetric toroidal systems, using the method of matched asymptotic expansions. At each singular surface in the plasma, the small-x asymptotic solutions of the ideal MHD outer-region equations are matched to the large-x asymptotic solutions of the resistive inner-region equations, with x being the distance from the singular surface. The success of this method depends upon accurate asymptotic solutions of the resistive inner region equations. Extensive studies have shown that there are not only regimes of excellent agreement with straight-through methods, without asymptotic matching, but also regimes of strong disagreement. In an effort to find the cause of this discrepancy, we present here a different method of constructing asymptotic solutions of the inner region equations and we study the convergence properties of the new and old solutions.
Effects of cavitation on Kármán vortex behind circular-cylinder arrays: A molecular dynamics study
Authors: Asano Yuta , Watanabe Hiroshi , Noguchi Hiroshi
Published: January 2020

The effects of cavitation on the flow around a circular-cylinder array are studied by using a molecular dynamics simulation. Cavitation significantly affects vortex shedding characteristics. As the cavitation develops, the vibration acting on the cylinders decreases and eventually disappears. The further cavitation development generates a longer vapor region next to the cylinders, and the vortex streets are formed at further positions from the cylinders. The neighboring Kármán vortexes are synchronized in the antiphase in the absence of the cavitation. This synchronization is weakened by the cavitation, and an asymmetric wake mode can be induced. These findings help mechanical designs of fluid machinery that include cylinder arrays.
Computer modeling investigation of MgV2O4 for Mg-ion batteries
Authors: Kuganathan Navaratnarajah , Davazoglou Konstantinos , Chroneos Alexander
Published: January 2020

MgV2O4 is a vanadium spinel considered for rechargeable magnesium ion batteries. Its defect chemistry, solution of dopants, and the diffusion of Mg ions are investigated using advanced atomistic modeling techniques. The energetically most favorable defect is Mg–V anti-site cluster (0.53 eV/defect) assuming that a small percentage of Mg2+ and V3+ ions would exchange their positions, particularly at higher temperatures. Reaction energies for the loss of MgO via MgO Schottky and the formation of Mg vacancies via Mg Frenkel are calculated to be 5.13 eV/defect and 5.23 eV/defect, respectively, suggesting that the concentrations of these two defects will not be significant. The most favorable diffusion mechanism of Mg ions is a three-dimensional pathway, where the activation energy of migration is 0.52 eV. The formation of Mg interstitials and O vacancies can be facilitated by doping with Co2+ at the V site in MgV2O4. The electronic structures of the favorable dopants calculated using the density functional theory are discussed.
Experimental investigation on the gas-liquid flow patterns in a centrifugal pump during self-priming process
Authors: Qian Heng , Mou Jiegang , Wu Denghao , Ren Yun , Zheng Shuihua , Zhu Zhibing
Published: January 2020

Self-priming pumps are widely used for irrigation, water treatments, and industrial areas due to the self-priming capacity. As we know, the gas-liquid flow pattern during the self-priming process is very complex and still not fully understood. In this study, a visualization test was performed to reveal gas-liquid two-phase flow patterns in a transparent pump during the self-priming process by using high-speed photography. The dynamic change of water column in the inlet-pipe and outlet-pipe was recorded by a digital camera, and the internal flow states of the test pump were recorded by a high-speed camera under different positions and different frame rates. First, the transient gas-liquid flow patterns during the self-priming process were revealed. In the initial stage, a large amount of gas was sucked into the impeller and the water level rose fast in the inlet pipe and then kept steady. With the increase in volume of gas in the impeller, plenty of bubbles were generated rapidly because of the mixing of gas and liquid inside the impeller. Some small bubbles were transported to the gas-liquid separation chamber by the centrifugal force, while rest of bubbles still circulated together with the impeller. In addition, the light gas was discharged to the outlet pipe and the heavy water was reserved inside the chamber due to the effect of gravity force. Afterwards, part of the water and gas flowed back to the impeller through the reflux hole. Second, the dynamic evolution of bubble formation was captured. Many bubbles appeared as the gas pocket was crushed by the blade surface or the jet flow. In general, the self-priming capacity was determined by the mixing rate of gas and liquid, the transporting rate of a gas-liquid mixture from the volute to the gas-liquid separation chamber, and the separating rate of gas from liquid.
Pattern method for higher harmonics from macromolecular orientation in oscillatory shear flow
Authors: Giacomin A. J. , Jbara L. M. , Saengow C.
Published: January 2020

For a suspension of rigid dumbbells, in any simple shear flow, we must first solve the diffusion equation for the orientation distribution function by a power series expansion in the shear rate. Our recent work has uncovered the pattern in the coefficients of this power series [L. M. Jbara and A. J. Giacomin, “Orientation distribution function pattern for rigid dumbbell suspensions in any simple shear flow,” Macromol. Theory Simul. 28, 1800046-1–1800046-16 (2019)]. Specifically, we have here used this pattern on large-amplitude oscillatory shear (LAOS) flow, for which we have extended the orientation distribution function to the 6th power of the shear rate. In this letter, we embed this extension into the Giesekus expression for the extra stress tensor to arrive at the alternant shear stress response, up to and including the seventh harmonic. We thus demonstrate that the pattern method for macromolecular orientation now allows our harmonic analysis to penetrate the shear stress response to oscillatory shear flow far more deeply than ever.
Effects of uniconazole or ethephon foliar application on culm mechanical strength and lignin metabolism, and their relationship with lodging resistance in winter wheat
Authors: Ahmad Irshad , Kamran Muhammad , Guo Ziyan , Meng Xiangping , Ali Shahzad , Zhang Peng , Liu Tiening , Cai Tie , Han Qingfang
Published: January 2020

Lodging in plants is an important constraint that leads to yield losses and cause problems with mechanical harvesting. This research was aimed at determining the effects of foliar application of uniconazole or ethephon on lignin metabolism, characteristics of second basal internode and their relationship with lodging resistance in winter wheat (Triticum aestivum L.). In separate experiments, uniconazole was sprayed on the foliage at concentrations of 0, 15, 30 and 45 mg L–1, and ethephon at concentrations of 0, 50, 75 and 100 mg L–1 at the four-leaf stage. Foliar application of uniconazole or ethephon significantly reduced the lodging rate by increasing the lignin content and optimising basal-internode characteristics. Lignin content was significantly positively correlated with breaking strength, and negatively correlated with lodging rate, whereby the higher lignin content in the second basal internode significantly improved the lodging resistance and reduced the lodging rate in the wheat crop. Foliar application of uniconazole or ethephon also increased the breaking strength, internode diameter, wall thickness and internode plumpness of the second basal internode; maximum values were obtained with uniconazole at 30 mg L–1 and with ethephon at 75 mg L–1. Grain yield, lignin content and lignin-related enzyme activities of phenylalanine ammonia-lyase, tyrosine ammonia-lyase, cinnamyl alcohol dehydrogenase and peroxidase were all significantly improved with the foliar application of uniconazole or ethephon. These results suggest that lignin content in the second basal internode in wheat was closely related with lodging resistance. Foliar application of uniconazole or ethephon at the four-leaf stage reduced the lodging rate, and the concentration showing the greatest effects was 30 mg L–1 for uniconazole or 75 mg L–1 for ethephon.
Interpreting the sacred in dark tourism.
Authors: Nitasha Sharma Nitasha Sharma
Published: January 2020

This chapter looks at social constructions of pilgrimage and dark tourism sites through examining death-related rituals in the city of Varanasi, Uttar Pradesh, India. In doing so, it investigates how tourists engage with and understand sacred spaces through examining ontological, phenomenological and structural-functional theoretical perspectives of sacred space.
From burial spaces to pilgrimage sites: the changing role of European cemeteries.
Authors: Pliberšek L. , Basle N. , Lebe S. S.
Published: January 2020

This chapter examines the role of military cemeteries and their relationship to pilgrimage and tourism. In particular, focus is given to the element of scale, with cemeteries being viewed as individual pilgrimage sites, pilgrimage destinations, or one of several cemeteries along a pilgrimage itinerary. First, the chapter discusses the role and dimensions of cemeteries as burial places, as a form of cultural heritage, and as tourist attractions. Attention is then turned to discussing cemeteries as personal pilgrimage spaces, pilgrimage centres and nodal points along a pilgrimage itinerary.
Dark tourism or pilgrimage in the museum? Considering the case of Emmett Till's casket.
Authors: Cook M.
Published: January 2020

This chapter first provides an overview of the historical context of the life, murder and the subsequent trial of the killers of Emmett Till (an African-American boy who was lynched in 1955). Next, discussion shifts to the controversial decisions that the Smithsonian faced in their efforts to obtain Till's casket for eventual display in the National Museum of African American History and Culture (NMAAHC). Attention is then drawn on the literature on pilgrimage and dark tourism to analyse whether this exhibit and the broader museum constitute an example of dark tourism, pilgrimage, or both. Finally, there are some thoughts on how Till's casket is of great symbolic importance in the current racial climate in the USA.
Intracourt Dialogue
Authors: Corley Pamela , Ward Artemus
Published: January 2020

Dissenting opinions are part of the ongoing constitutional dialogue among elites both inside and out of the judiciary. In order to illustrate how dissents contribute to the ongoing constitutional dialogue among elites, we examine the effect of dissents on majority opinions in the US Supreme Court. We empirically assess their operation on the contemporary Court. We find that dissents with certain characteristics are more effective than others on prompting the majority opinion to cite and discuss them. Specifically, majority opinions cite and discuss dissents that have a negative emotional tone; contain formal, logical, and hierarchical thinking; use adverbs; have a mixed ideological coalition; and cite a high number of Supreme Court precedents. These results suggest that strategic dissenters will have more in-house impact than others.
Force national standards comparison in the interamerican system of metrology (SIM), 100 kN compression
Authors: Poblete Juan Christian Villarroel , Betancur Ivan David , Dájer Espeleta stides , Savarin Alejandro
Published: January 2020

This force comparison was performed between IDIC (Chile), INTI (Argentina) and INM (Colombia), members of the SIM region. Each laboratory used its national standard for the established measuring range. The comparison started in August 2013 and finished in December 2013. This comparison has an overlap with the force steps used in the CIPM Key Comparison CCM.F-K2.a.1, at force points 50 kN and 100 kN.

Main text

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 kcdb.bipm.org/.

The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
A macrorealistic test in hybrid quantum optomechanics
Authors: Marchese Marta , McAleese Hannah , Bassi Angelo , Paternostro Mauro
Published: January 2020

We discuss a scheme for macrorealistic theories of the Leggett–Garg form (Leggett and Garg 1985 Phys. Rev. Lett.
54 857). Our scheme is based on a hybrid optomechanical system. It seems reasonable to test these inequalities with an optomechanical system, since in an optomechanical cavity it is possible to create non-classical states of the mirror through a projective measurement on the cavity field. We will present the protocol to generate such non-classicality for a general optomechanical cavity and after we will carry out a theoretical test for one of the possible formulations of these inequalities using a hybrid optomechanical system. Specifically, the inequality will be investigated for an harmonic oscillator coupled to a two-level system, which replaces the light field of the cavity. The aim is to reproduce, with this system, the evolution of a single spin-1/2 for which the inequality is violated; this is achievable through the conditioning of the two-level system which will be used as an ancilla.
The Dawn of Multimessenger Astronomy
Authors: Cowen D. F.
Published: January 2020

The realization of multimessenger astrophysics is opening up a new field of exploration of the most energetic phenomena in the universe. Astrophysical messengers associated with each of the four fundamental forces reach detectors buried deep underground or underwater, spread across wide swaths of land, and orbiting high above us in space. Recent detection of coincident real-time signals amongst these experiments heralds the birth of high-energy multimessenger astronomy and enables us to begin exploring and understanding their astrophysical sources. The Astrophysical Multimessenger Observatory Network (AMON) is currently linking multiple current and future high-energy neutrino, cosmic ray, gamma ray and gravitational wave observatories into a single virtual system, facilitating real-time coincidence searches for multimessenger astrophysical transients. AMON will generate alerts that will enable rapid follow-up of potential electromagnetic counterparts. We present the science case, design elements, partner observatories, and status of AMON.
First results from the CUORE experiment
Authors: Alduino C. , Alfonso K. , Avignone III F. T. , Azzolini O. , Bari G. , Bellini F. , Benato G. , Bersani A. , Biassoni M. , Branca A. , Brofferio C. , Bucci C. , Camacho A. , Caminata A. , Canonica L. , Cao X. G. , Capelli S. , Cappelli L. , Cardani L. , Carniti P. , Casali N. , Cassina L. , Chiesa D. , Chott N. , Clemenza M. , Copello S. , Cosmelli C. , Cremonesi O. , Creswick R. J. , Cushman J. S. , D’Addabbo A. , D’Aguanno D. , Dafinei I. , Davis C. J. , Dell’Oro S. , Deninno M. M. , Domizio S. Di , Vacri M. L. Di , Dompe V. , Drobizhev A. , Fang D. Q. , Faverzani M. , Ferri E. , Ferroni F. , Fiorini E. , Franceschi M. A. , Freedman S. J. , Fujikawa B. K. , Giachero A. , Gironi L. , Giuliani A. , Gladstone L. , Gorla P. , Gotti C. , Gutierrez T. D. , Han K. , Heeger K. M. , Hennings-Yeomans R. , Huang H. Z. , Keppel G. , Kolomensky Yu. G. , Leder A. , Ligi C. , Lim K. E. , Ma Y. G. , Marini L. , Martinez M. , Maruyama R. H. , Mei Y. , Moggi N. , Morganti S. , Nagorny S. S. , Napolitano T. , Nastasi M. , Nones C. , Norman E. B. , Novati V. , Nucciotti A. , Nutini I. , O’Donnell T. , Ouellet J. L. , Pagliarone C. E. , Pallavicini M. , Palmieri V. , Pattavina L. , Pavan M. , Pessina G. , Pira C. , Pirro S. , Pozzi S. , Previtali E. , Reindl F. , Rosenfeld C. , Rusconi C. , Sakai M. , Sangiorgio S. , Santone D. , Schmidt B. , Schmidt J. , Scielzo N. D. , Singh V. , Sisti M. , Taffarello L. , Terranova F. , Tomei C. , Vignati M. , Wagaarachchi S. L. , Wang B. S. , Wang H. W. , Welliver B. , Wilson J. , Wilson K. , Winslow L. A. , Wise T. , Zanotti L. , Zhang G. Q. , Zimmermann S. , Zucchelli S.
Published: January 2020

CUORE (Cryogenic Underground Observatory for Rare Events) is a ton-scale experiment aiming to the search of neutrino-less double beta decay in 130Te with a projected sensitivity on the Majorana effective mass close to the inverted hierarchy region. The CUORE detector consists of a segmented array of 988 TeO2 bolometers, organized in 19 towers and operated at a temperature of about 10 mK thanks to a custom cryogenic system which, besides the uncommon scale, observes several constraints from the radio-purity of the materials to the mechanical decoupling of the cooling systems. The successful commissioning of the CUORE cryogenic system has been completed early in 2016 and represents an outstanding achievement by itself. The installation of the detector proceeded along 2016 followed by the cooldown to base temperature at the beginning of 2017. The CUORE detector is now operational and has been taking science data since Spring 2017. With the first ~3 weeks of collected data, we present here the most stringent constraint on the 130Te half-live for the neutrino-less double beta decay.