bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessing the Impact of Land Use Changes on Net Primary Productivity in Wuhan, China
Authors: Gu Yan , Shao Zhenfeng , Huang Xiao , Fu Yuanhao , Gao Jiyuan , Fan Yewen
Published: March 2022

Since 2000, major changes have taken place in Wuhan city. Land use and land cover (LULC) has changed significantly, characterized by increased construction land, reducing farmland, grassland, and forest land due to the rapid urbanization process. Taking advantage of LULC data and Moderate
Resolution Imaging Spectroradiometer Net Primary Production (MODIS NPP) data from 2000 to 2020, we analyze the impact of LULC type transformation on NPP, reveal the relationship between LULC type and NPP, and quantify the impact of urban expansion on NPP by taking Wuhan, China as a study case.
The results showed that: 1) the transformation from farmland and grassland to construction land was a dominant LULC change type in Wuhan during the investigated period; 2) there exists a significant negative correlation between NPP and changes in farmland, woodland, and grassland area; 3)
the distance from the city center has a significant positive correlation with NPP, and the dynamics of NPP vary in different regions; 4) there is a significant positive correlation between NPP and night light data. The results of this study provide scientific references for the formation of
greening construction and sustainable development strategies in Wuhan.
Differences between rural and urban marriage seasonality from the early 19th to the early 20th centuries in Northern Belgium
Authors: Matsuo Hideko , Matthijs Koen
Published: March 2022

This paper examines the impact of secularization on marriage seasonality in two Flemish provinces and Brussels, using place of marriage to distinguish between rural and urban areas. The evolution of the level of church control and secularization between the early 19th and the early 20th centuries is measured through a daily Lent and Advent (DLA) marriage index. A low index value points to a higher level of church control and a lower level of secularization, while a high index value points to a lower level of church control and a higher level of secularization. Sub-samples of civil marriage registers are analysed. DLA-index values are low in the early 19th century but increase slowly throughout the rest of the 19th century albeit with geographical variations. Spatial differences can be explained through different socio-economic and cultural characteristics of the population. Still, similar underlying factors across locations are identified: changes are consistently affected in cities, and driven by non-native brides, skilled and unskilled, but only partially observing for elites. Religious rule of Advent is more moderate than the one for Lent, where less Lent effects are observed.
Struktur Populasi Ikan Baronang pada Ekosistem Lamun Di Pesisir Pulau Bintan
Authors: Jemi Jemi , Karlina Ita , Nugraha Aditya Hikmat
Published: March 2022

Salah satu ekosistem pesisir yang dapat ditemukan di pesisir Pulau Bintan yaitu  ekosistem lamun. Ikan baronang merupakan ikan ekonomis penting yang berasosiasi dengan padang lamun. Kondisi struktur ekosistem lamun yang berbeda di perairan pulau Bintan diduga dapat berpengaruh terhadap persebaran ikan baronang pada ekosistem lamun. Penelitian ini bertujuan untuk mendeskripsikan kondisi tutupan lamun pada beberapa lokasi dan mendeskripsikan struktur populasi ikan baronang (Siganus sp) pada ekosistem lamun dengan tutupan berbeda di  perairan pulau Bintan. Metode sampling tutupan lamun menggunakan transek kuadrat berukuran 50 x 50 cm dan sampling ikan baronang menggunakan jaring insang dasaran (bottom gill net). Diperoleh 8 jenis lamun yang tersebar di 4 stasiun penelitian. Tutupan lamun tertinggi terdapat di stasiun Pengudang dengan nilai 65,20% dengan kondisi kaya/padat.  Terdapat 5 jenis ikan baronang. Jenis ikan baronang yang memiliki kelimpahan tertinggi yaitu Siganus canaliculatus. Tidak terjadi perbedaan yang signifikan untuk persebaran jenis ikan baronang pada lokasi penelitian  One of the ecosystems that can be found on the coast of Bintan Island is the seagrass ecosystem. SIganus sp are economical fish associated with seagrass beds. The structure of the seagrass ecosystem is thought to have an effect on the distribution of Siganus sp in the seagrass ecosystem. This study aims to describe the condition of seagrass cover at several locations in the waters of Bintan Island and to describe the population structure of Siganus sp in seagrass ecosystems with different cover in the waters of Bintan Island. The seagrass cover sampling method used a quadratic transect measuring 50 x 50 cm and the Siganus sp fish sampling used a bottom gill net. Obtained 8 types of seagrass spread over 4 research stations. The highest seagrass cover was found at Pengudang station with a value of 65.20% with rich/dense conditions. There are 5 types of baronang fish. The type of baronang fish that has the highest abundance is Siganus canaliculatus. There is no significant difference for the distribution of baronang fish species at the study site.
Development of Peak Ground Acceleration Map of Semarang Based on Indonesian Seismic Code 2019
Authors: Partono Windu , Irsyam Masyhur , Nazir Ramli , Asrurifak Muhammad , Kistiani Frida , Sari Undayani Cita
Published: March 2022

Surface peak ground acceleration (PGAM) needs for seismic forces of basement and retaining structures design.  The PGAM value can be calculated using bedrock peak ground acceleration (MCEG) and multiplied it with site coefficient FPGA. For building design purposes, the MCEG value can be calculated based on the combination of DSHA (Deterministic Seismic Hazard Analysis) and PSHA (Probabilistic Seismic Hazard Analysis). Compared to the previous 2012 website response spectrum design which is displayed the PGAM value, only MCEG value at site position can be obtained from the new 2021 response spectrum design website. This paper describes the development of PGAM distribution of Semarang using Visual Basic programming language software. The distribution of DSHA and PSHA (2500 return periods) combination analysis for developing MCEG value also describes in this paper. The analysis was performed based on the earthquake record data from 1900 to 2016. The PGAM analysis was performed at 203 soil boring investigation positions and using FPGA site coefficients of SNI 1726:2019. The minimum and maximum PGAM distribution values at the study area are in between 0.45 through 0.55 g and the maximum PGAM is distributed at the northern part of the study area.
The Effects of Introducing Advertising in Pay TV: A Model of Asymmetric Competition between Pay TV and Free TV
Authors: Dietl Helmut , Lang Markus , Lin Panlang
Published: March 2022

The television broadcasting industry is of crucial economic and social importance. Traditionally, this industry has been dominated by free-to-air TV (FTV) but due to technological progress, subscription-based pay TV (PTV) has emerged as a competing business model. A key question for the PTV broadcasters is whether to air commercials in addition to charging subscription fees. Based on a theoretical model of asymmetric competition between a PTV and an FTV broadcaster, we examine the effects of placing PTV advertising on broadcaster market strategies, viewer demands, broadcaster profits and consumer surplus. We find that introducing advertising on PTV can induce a higher viewer demand on this channel but a lower viewer demand on the FTV channel. Surprisingly, consumers can benefit through the introduction of advertising in PTV and broadcaster profits can increase if the viewer disutility of advertising is sufficiently large. Our study provides an analytical framework for choosing and implementing an optimal PTV strategy when an FTV competitor preexists in the market. Furthermore, our study derives implications for policymakers and regulatory authorities by showing that additional PTV advertising is not necessarily socially undesirable due to the strategic market reactions.
Sample age effect on parameters of dynamic nuclear polarization in certain difluorobenzen isomers/MC800 asphaltene suspensions
Authors: Ovalioglu Hüseyin
Published: March 2022

Because of magnetic spin–spin interactivity between 19F nucleus of the solvent and delocalized electrons on the MC800 asphaltene, the Overhauser dynamic nuclear polarization (DNP) method is able to give a substantial boost in the signal acquired from studies focused on nuclear magnetic resonance (NMR). The suspensions of asphaltene in difluorobenzene isomers were studied using Overhauser effect type DNP and NMR investigations at room temperature in a small magnetic field of 1.53 mT. The used asphaltene was obtained from MC800 liquid asphalt from Heavy Iran. Each sample of the solvent medium was produced at three different concentrations of asphaltene. These samples were stored in the refrigerator for 7 years, until DNP parameters were found by new DNP tests. As a result, the influence of sample age on parameters of DNP was studied, and then the findings were analyzed.
New approach to analysis of railway track dynamics – Rail head vibrations
Authors: Czyczuła Włodzimierz , Błaszkiewicz-Juszczęć Dorota , Urbanek Małgorzata
Published: March 2022

The article presents an original approach to the analysis of railway track dynamics. The “beam-inside-beam” concept is introduced as a dynamic generalisation of the static head-on-web effect, based on the two-layer model of rail. Rail head is a distinguished element of the rail. The system of distributed moving loads excites rail head as a beam supported by the rail web being considered as a viscoelastic layer. Rail head vibration is a kinematic excitation of the whole rail profile, including the rail head. The whole rail is also considered as a beam on viscoelastic foundation with parameters used in typical analyses of railway track dynamics. Vibrations of the whole rail obtained from the analysis of the two-layer “beam-inside-beam” model are compared with vibrations of typical one-layer track model. It is known that the static head-on-web effect is very limited. The range of significant rail head displacements covers nearly 0.6 m of area centred around the wheel position. This observation is also valid in the case of moving constant load. In other words, the dynamic effect of rail head vibrations in the case without imperfections type of track-vehicle is practically the same as in the static head-on-web case. Nevertheless, the analysis of track imperfections impact with various factors influencing the system behaviour, like the axles load and configuration, the track elastic parameters, the length of imperfection, or the train speed, show that the head-on-web effect is significant and should be analysed in more detail. For this purpose, a new model “beam-inside-beam” is proposed. The Fourier series are used to solve the two considered models. The load and unknown functions in the models’ solutions are expanded in the arbitrarily assumed interval which practically covers non-zero track response for the analysed system of parameters (group of wheels). This solving method for equation of motion was experimentally validated in the paper by Czyczula et al. (2017). Validation of the “beam-inside-beam” model is considered as future work and the current article should be recognised as a preliminary study of the analysed effects under assumption of being purely theoretical investigation so far, although forming hierarchically organised building of more complex rail models is possible to partially verify in further steps of modelling process.
TRPM3 in the eye and in the nervous system – from new findings to novel mechanisms
Authors: Behrendt Marc
Published: March 2022

The calcium-permeable cation channel TRPM3 can be activated by heat and the endogenous steroid pregnenolone sulfate. TRPM3’s best understood function is its role as a peripheral noxious heat sensor in mice. However, the channel is expressed in various tissues and cell types including neurons as well as glial and epithelial cells. TRPM3 expression patterns differ between species and change during development. Furthermore, a plethora of TRPM3 variants that result from alternative splicing have been identified and the majority of these isoforms are yet to be characterized. Moreover, the mechanisms underlying regulation of TRPM3 are largely unexplored. In addition, a micro-RNA gene (miR-204) is located within the TRPM3 gene. This complexity makes it difficult to obtain a clear picture of TRPM3 characteristics. However, a clear picture is needed to unravel TRPM3’s full potential as experimental tool, diagnostic marker and therapeutic target. Therefore, the newest data related to TRPM3 have to be discussed and to be put in context as soon as possible to be up-to-date and to accelerate the translation from bench to bedside. The aim of this review is to highlight recent results and developments with particular focus on findings from studies involving ocular tissues and cells or peripheral neurons of rodents and humans.
Performance analysis of grid interactive single-phase solar powered fault tolerant cascaded inverter
Authors: Rajesh Jami , Jayaram Nakka , Kishore Pulavarthi Satya Venkata , Jakkula Swamy
Published: March 2022

Grid integration of solar photovoltaic (PV) systems is becoming popular recently due to the merits of stable support to conventional grid, limiting global warming and reduced emissions. However, maintaining capacitor voltage balancing, unity power factor, sinusoidal grid current and harmonic profile improvement are the challenging tasks owing to change in irradiation conditions. Multi-level inverters in grid connected systems will enhance the power quality of the system in terms of voltage and current total harmonic distortion. This paper proposes a highly reliable, robust and modular single phase solar PV fed fault tolerant hybrid cascaded H-bridge inverter with individual voltage/current control strategy for grid integration. Higher reliability and modularity, power factor correction, able to with stand without degrading the performance of the topology even under faulted conditions and harmonic profile improvement are the main objectives of the proposed system. The proposed system has been simulated and validated with experimental results on the developed prototype for different irradiation conditions and tested the performance of the topology with creation of faults on different modules at different times.
The Pd-rich part of the Pd–B phase diagram
Authors: Georg Berger Tilmann , Leineweber Andreas , Mittemeijer Eric Jan
Published: March 2022

The Pd–B system in the composition range of the solid solution PdBy has been the subject of a number of investigations as it provides an attractive model system for interstitial compounds. No consensus about the crystal structures and phase boundaries, particularly in the low-temperature regime, has been reached in the earlier works. In the light of very recent results on the crystal structure and composition ranges of the low-temperature phases, on the basis of X-ray, electron, and neutron diffraction analyses, a tentative phase diagram is presented which is compatible with practically all previous results.
Influence of electric field strength applied during the solution heat treatment of the Al–Mg–Si–Cu Alloy AA6111
Authors: Jung Kang , Conrad Hans
Published: March 2022

In the present paper, the effect of electric field strength in the range E = 0.1 – 5.0 kV/cm applied during the solution heat treatment (SHT) of the AA6111 alloy at 475° –550 °C has been determined employing resistivity. An increase in the as-quenched resistivity ρ
w occurred for all field strengths, the increase being relatively rapid up to E ≈ 1 kV/cm and only slight, if at all, for higher fields. Analysis of the results gave that the field reduced the enthalpy, entropy and Gibbs free energy of solution, the amount of reduction increasing with field strength. The electric current, which occurred with application of the field during SHT, ranged from (7 × 10 –3 to 4 × 102) μA, increasing with field strength and SHT temperature, but decreasing with time during the SHT. The role of the current in the enhancement of ρ
w by the field is not clear.
Development of cube recrystallization textures in high-purity Al
Authors: Umezawa Atsushi , Inagaki Hirosuke
Published: March 2022

High-purity (99.99 wt.%) Al containing 50 wt. ppm Cu was cold rolled to 98% reduction in thickness and annealed by varying the heating rate of annealing and annealing cycles. Textures developed at various stages of annealing were investigated with the orientation distribution function analysis. The observed results were compared with those obtained on standard high purity (99.99 wt.%) Al without Cu addition. In slow heating rate annealing, it was found that in high purity Al the addition of 50 wt.ppm Cu significantly enhanced the development of {100}<001> recrystallization textures. Intensities of {100}<001> developed in high purity Al with 50 wt. ppm Cu were about twice as high as those observed in high purity Al without Cu addition. {123}<634> R orientations were completely eliminated by the addition of 50 wt. ppm Cu. In rapid heating annealing, on the other hand, annealing at temperatures above 325 °C resulted in the formation of very coarse recrystallized grains with weak {100}<001> recrystallization textures irrespective of Cu content. Such grain coarsening could be suppressed by pre-annealing at temperatures between 225 and 300 °C. In the specimens subjected to this pre-annealing, strong {100}<001> recrystallization textures could be obtained, even if they were annealed with a rapid heating rate in final annealing.
Formation of cube recrystallized grains in high-purity Al
Authors: Umezawa Atsushi , Inagaki Hirosuke
Published: March 2022

In high-purity 4 N (99.99 wt.%) Al containing 50 wt.ppm Cu, very strong {100}<001> recrystallization textures are developed after 98% cold rolling and annealing at 500 °C. They are about three times stronger than those observed in standard high-purity 4 N Al without Cu addition. In this paper, the mechanism of the formation of such strong {100}<001> recrystallization textures were investigated in detail by using the EBSP (electron backscatter pattern) analysis.

It was found that, at the earliest stage of recrystallization, {100} <001>-recrystallized grains were nucleated by forming a row lying parallel to the rolling direction and growing preferentially within the elongated deformed grain in which they were nucleated. Most of these {100}<001>-recrystallized grains had orientations very near to the exact cube orientations. {100}<001>-recrystallized grains in this materials were characterized by their rapid growth, which was observed at the later stages of recrystallization. Since they were surrounded by deformed regions having very strong β-fiber rolling textures formed by heavy cold rolling, their grain boundaries were high-angle grain boundaries with high mobility. Assisted further by high stored energy introduced by heavy rolling reductions, {100}<001>-recrystallized grains could grow very rapidly, traversing readily several deformed grains. In this material, {100}<001>-recrystallized grains were not nucleated so abundantly. However, {100}<001>-recrystallized grains were nucleated much earlier and grew much faster than recrystallized grains with other orientations. They were, therefore, always larger than recrystallized grains with other orientations. Due to such size advantages, {100}<001>-recrystallized grains could rapidly consume fine-recrystallized grains with other orientations during the subsequent grain growth process. As a result, microstructures observed after annealing at 500 °C for 2 h consisted mostly of coarse {100}<001>-recrystallized grains slightly misoriented with each other. It is, thus, rapid growth of few {100}<001>-recrystallized grains during recrystallization, and their preferential grain growth, that enhance the development of very strong {100}<001> recrystallization textures in this high-purity Al. Cu seems to suppress nucleation of recrystallized grains with other orientations.
Decomposition kinetics of expanded austenite with high nitrogen contents
Authors: Christiansen Thomas , Somers Marcel A. J.
Published: March 2022

This paper addresses the decomposition kinetics of synthesized homogeneous expanded austenite formed by gaseous nitriding of stainless steel AISI 304L and AISI 316L with nitrogen contents up to 38 at.% nitrogen. Isochronal annealing experiments were carried out in both inert (N2) and reducing (H2) atmospheres. Differential thermal analysis (DTA) and thermogravimetry were applied for identification of the decomposition reactions and X-ray diffraction analysis was applied for phase analysis. CrN precipitated upon annealing; the activation energies are 187 kJ/mol and 128 kJ/mol for AISI 316L and AISI 304L, respectively. Isothermal stability plots for expanded austenite developed from AISI 304L and AISI 316 were obtained.
Elevated temperature tensile properties of an extruded aluminium alloy reinforced with SiCp
Authors: Özdemir İ. , Önel K.
Published: March 2022

Elevated temperature tensile properties of AlSi7Mg (Al-7 %Si– 0.7 %Mg) and its composites with 10 and 20 vol.% SiCp in the as-extruded form were investigated. The cast ingots of the matrix alloy and the composites were produced by the permanent die casting technique and extruded at 480 °C using an extrusion ratio of 10 : 1. The high-temperature tensile tests were carried out over the temperature range from 25 to 430 °C. Mechanical properties after extrusion show that the composite samples have strength values superior to that of the matrix alloy at ambient temperature. At elevated temperatures the results indicate that the composites exhibit good strength retention up to 300 °C, above which the strengthening effect of SiCp disappears as the temperature is increased. The strain rate sensitivity “m” was observed to be 0.11 for the matrix alloy, 0.13 and 0.07 for the composites with 10 and 20 vol.% SiCp, respectively, at a test temperature of 430 °C in the strain rate range from 4 × 10 –5 to 4 × 10– 2 s– 1.
Formation, stability, and presence of magnesium nitride in magnesium recycling processes
Authors: Bauer Christoph , Mogessie Aberra , Galovsky Ulrike
Published: March 2022

In this study an attempt has been made to identify analytical methods for detecting magnesium nitride, and document in which part of the magnesium recycling process this phase is concentrated. The samples were taken from a continuous fluxfree recycling session, where an AZ91D magnesium alloy was remelted and purified by blowing nitrogen through the melt. Exothermic reactions took place when magnesium nitride reacted to ammonia and Brucite and also when aluminium nitride reacted to ammonia and Gibbsite in a moisture-bearing environment. Because of this, it was essential to avoid any contact with moisture during the whole sampling and preparation process. The samples were exclusively handled in an argon atmosphere. Due to their crystallinity and Raman activity the nitrides were detected with X-ray diffraction and Raman spectroscopy, respectively. With the scanning electron microscope it was difficult to analyze small concentrations of nitrides since large, stable crystals were absent and the carbon coating absorbs the nitrogen Kα line.

The Mg-alloy was found to be free of impurities. Although nitrides were expected to be concentrated in the slag because of their greater density, they were found adhering at the nitrogen bubbles and accumulating in the dross. Large amounts of oxides were concentrated in the slag.
Recent progress in the area of bulk metallic glasses
Authors: Löffler Jörg F.
Published: March 2022

Bulk metallic glasses (BMGs) form a new class of alloys which can be manufactured amorphously at a cooling rate of less than 100 K/s and in dimensions of several centimeters. Because of their particular characteristics, these glassy materials have great potential for deployment as structural and functional materials. The mechanical, magnetic, and thermophysical properties of this new materials group and the advantages they promise for the processing and manufacturing of components are presented. The possibilities for deploying bulk metallic glasses in medical devices and lightweight construction are also set out. In these two areas, we discuss some results as to the biocompatibility of metallic glasses and their potential use in vascular intervention, as well as the properties of light-metal-based bulk metallic glasses in connection with their potential as a construction material. We also present ideas concerning the development of corrosion-resistant Mg-based glasses, and the manufacture and processing of light-metal-based composites.
Phase decomposition and precipitation of metastable A2 phase in B2 ordered Co–Al–Fe alloys
Authors: Kozakai Takao , Koyama Toshiyuki , Doi Minoru
Published: March 2022

Phase decomposition in rapidly solidified Co–Al – Fe B2 alloys during isothermal ageing at 923 K has been investigated by means of X-ray diffraction and transmission electron microscopy. At the early stage of ageing, A2 disordered particles precipitate inside B2 matrix grains, being aligned along the <100> direction of the matrix, and equilibrium A1 phase (α-Co) is also formed mostly on grain boundaries. With further ageing, the plate-like A2 particles increase in size. On the other hand, the A1 phase on grain boundaries increases in size and also spreads into the B2 grain like tree branches as so-called Widmanstätten precipitate. Finally, the A2 phase disappears. The A1 phase remains on grain boundaries and also inside the B2 grains as spherical particles. Using the composition gradient method, the metastable precipitation limit of the A2 phase, that is the metastable phase boundary B2/(A2 + B2), was experimentally determined at 923 K. It extends smoothly into the stable A2 + B2 two-phase field on the Co–Fe side of the ternary Co–Al –Fe system.
A critical analysis of the composite model as applied to high-temperature creep of Al and an Al–Mg alloy
Authors: Zehetbauer M. , Schafler E. , Dobeš F. , Milička K.
Published: March 2022

The composite model which has been created by Mughrabi, and developed by several other researchers, is analyzed with respect to high-temperature creep of Al and an Al– Mg alloy. Data for structural parameters such as local and global internal stresses, and dislocation densities have been obtained from X-ray line profile analyses and stress dip tests. Based on the composite model, quantitative relations have been derived which convert the internal stresses gained from X-ray profile analysis into those obtained from stress dip tests. This allowed for a detailed check of the composite model and its formalism describing local and global external and internal stresses, and local and global dislocation densities, during creep at high temperatures. While the local and global internal stresses show an excellent coincidence, the dislocation densities and subboundary volume fractions derived from experiment and modelling show certain deviations; however, these can be related to simplifications of equations used which are not part of the composite model.
Liquid–liquid interfacial tension in themonotectic alloy (Al34.5Bi65.5)95Si5 (wt.%)
Authors: Kaban Ivan , Hoyer Walter
Published: March 2022

The liquid – liquid interfacial tension and the density difference of the coexisting phases in the immiscible alloy (Al34.5Bi65.5)95Si5 (wt.%) have been measured between 873 and 1238 K. The interfacial tension equals (73.0 ± 3.6) mN/m at 873 K and it decreases with increasing temperature proportionally to (1 – T/T
C)
δ
. The critical-point exponent δ = 1.38, and the critical temperature T
C = 1410 K were determined from the experimental data.
Influence of Sb additions on surface tension and density of Sn–Sb, Sn–Ag–Sb and Sn–Ag–Cu–Sb alloys: Experiment vs. modeling
Authors: Moser Z. , Gąsior W. , Pstruś J. , Ohnuma I. , Ishida K.
Published: March 2022

Surface tension and density measurements by maximum bubble pressure and dilatometric techniques were carried out in an extensive range of temperature on liquid alloys close to the ternary eutectic Sn3.3Ag0.76Cu with different Sb content. It has been found that the addition of Sb to Sn, Sn–Sb, to binary eutectic Sn–Ag and to Sn3.3Ag0.76Cu decreases the surface tension and density. The values of the surface tension calculated by the Butler model and by the method based on the binary alloys surface tension data with the ternary and quaternary correction factors were compared with the experimental results. The best agreement between the measured and the calculated values was observed for the model comprising the binary data with the correction factors.
An indirect approach to measure glass transition temperature in metallic glasses
Authors: Jin H. J. , Lu K.
Published: March 2022

Glass transition behavior of metallic glasses under some extraordinary conditions (such as under high pressures) remains unexplored. Conventional measurements of glass transition temperature, T
g, are very difficult to perform under these extraordinary circumstances. In the present paper, we introduce an indirect approach to characterize glass transition, using enthalpy recovery experiments. With annealing deeply relaxed glassy samples and subsequent DSC measurements, a variation of enthalpy change upon heating with annealing temperature can be obtained. The variation of enthalpy change, a signature of glass transition, was found to correlate well with the directly measured DSC curves for the glass transition. This unique method was successfully applied in determining T
g of several metallic glasses under hydrostatic high pressures and compression stresses.
Comparison of thermodynamic data of the ternary Cu–Sn–Zn system, measured with the EMF and with the calorimetric method
Authors: Knott Sabine , Mikula Adolf
Published: March 2022

The enthalpy of mixing of the ternary Cu –Sn–Zn system was measured using a Calvet-type calorimeter. The investigations were carried out along the three cross sections Cu : Sn = 1 : 2, 1 : 1, and 2 : 1. Zn was added in the concentration range between 0 and 50 at.%.

The calorimetric results were compared with EMF data investigated in an earlier work by Peng and Mikula [1]. The results of the calorimetric measurements show very good agreement in the copper-rich region, compared with the EMF measurements, but in the Cu : Sn = 1 : 2 cross section the results do not fit perfectly. The difference between both measuring methods was at the most ΔH = 300 J/mol at the cross section Cu : Sn = 1 : 1 and ΔH = 150 J/mol at the Cu : Sn = 2 : 1 cross section.
Thermodynamic analysis of structural transformations induced by annealing of amorphous Si–C–N ceramics derived from polymer precursors
Authors: Golczewski Jerzy Andrzej
Published: March 2022

Thermodynamic modeling has been used to explain structural transformations induced by heat treatment of amorphous Si –C–N ceramics derived from polymers. Nanocrystalline silicon carbide and nanocrystalline silicon nitride identified in the ceramic microstructure have been regarded as metastable NASIC and NASIN phases in the Si–C–N system. The Gibbs energies G(NASIC) and G(NASIN) have been derived and used together with the previously modeled Gibbs energy of the amorphous am-SICN to compute metastable phase diagrams. Computational results allow explanation of the crystallization process of amorphous Si –C–N ceramics. According to this model, the temperature of invariant reaction between carbon and silicon nitride changes with the growth of nanocrystallites, which explains the dependence of the thermal stability on the ceramic microstructure.
Thermodynamic properties of B2-AlFeNi alloys: modelling of the B2-AlFe and B2-AlNi phases
Authors: Oates W. A. , Bencze L. , Markus T. , Hilpert K.
Published: March 2022

Results from our recent simultaneous measurement of all three component activities by Knudsen effusion mass spectrometry, together with results available in the literature from vacancy concentration and calorimetric measurements, have been used in a thermodynamic modelling study. The results of this modelling for the binary B2-AlFe and B2-AlNi phases are presented in this communication. A four-sublattice cluster energy model in the point approximation has been used for the configurational contributions to the Gibbs energy. Excitational free energies are incorporated into the configurational energy and non-configurational contributions are considered to be decoupled from the configurational. The modelling has been found to lead to good agreement between calculated and experimental results for both the thermodynamic properties and the vacancy concentrations. It is clear that B2-AlFe is an antisite defect compound at both the lowest and highest temperatures with vacancy defects only predominating, and to only a small degree, at stoichiometry in an intermediate temperature range. In the case of B2-AlNi, however, vacancy defects predominate at stoichiometry over the whole temperature range so that it can be correctly described as a near-triple defect compound.
Kinetics of precipitate formation in (Ti
x
W
y
Cr
z
)B2 solid solutions: influence of Cr concentration and Co impurities
Authors: Schmidt Harald , Fotsing Roland E. , Borchardt Günter , Schmalzried Clemens , Telle Rainer
Published: March 2022

Supersaturated (Ti0.5 – x
W0.5Cr
x
)B2 (x = 0, 0.1, 0,2) solid solutions were produced by reaction sintering of transition metal diboride powders at a pressure of 60 MPa at 1800 °C. The formation kinetics of W2B5 precipitates were investigated at lower temperatures by X-ray diffractometry (XRD) and secondary electron microscopy (SEM). The precipitation rate constants as a function of reciprocal temperature show non-monotonic behaviour in the range between 1450 and 1700 °C with a maximum at about 1650 °C. At low temperatures, Arrhenius behaviour is approximately valid, where the precipitation kinetics are dominated by the diffusion of the transition metals. In contrast, at temperatures higher than 1650 °C, the precipitation rates decrease rapidly, since supersaturation, and consequently nucleation, is strongly reduced. The rate constants of precipitation are identical within error limits for Cr concentrations of x = 0.1 and x = 0.2, however, they are significantly lower for x = 0. This means that the addition of small amounts of Cr accelerates the precipitate formation, while further addition has no further influence. Samples resulting from powders which were high-energy milled with WC/Co hard balls before reaction sintering show an increased density of precipitated crystallites but no increased rate constants of precipitation. This result can be explained under the assumption that for these samples a significant amount of additional pre-existing nuclei was present before precipitation starts, which were formed by heterogeneous nucleation at Co impurities, introduced by the milling process.
The Effect of Ti–B and Sr on the mechanical behaviour of the Zinc–Aluminum-based ZA-12 alloy produced by gravity casting
Authors: Can Kurnaz S. , Sevik Hüseyin , Türk Ahmet , Ozsarac Uǧur
Published: March 2022

In this study, the effect of Ti –B (0.05 – 0.7 wt.% Ti, 0.01 – 0.13 wt.% B) and Sr additions (0.05 – 0.7 wt.%) on the hardness, ultimate tensile strength (UTS), strain and fatigue properties of the gravity cast Zn – Al-based ZA-12 alloy was investigated. While the Ti –B additions had no significant effect on the hardness of the alloys, the Sr additions lowered the hardness by a small amount. UTS and fatigue resistance of the ZA-12 alloy increased with 0.05 wt.% Ti, but the addition of 0.05 wt.% Sr to the standard alloy did not change these properties significantly. In excess of 0.05 wt.% Ti and Sr, the UTS and fatigue resistance of the alloys decreased and reached a lower value than that of the standard alloy. The failure strain only increased for the ZA-12 alloy containing 0.05 wt.% Ti, then decreased with further increase in Ti content. The failure strain values of the alloys decreased with addition of Sr. Metallographic examination indicated that the addition of Ti –B strongly modified the microstructure of the standard ZA-12 alloy, but Sr did not. Ti and Sr have also formed complexshaped intermetallic compounds, which were identified as Al5Ti2Zn and Zn5Al3Sr by X-ray diffraction and EDS analyses. It can be suggested that these particles cause a decrease in UTS, fatigue resistance, and strain to failure of the ZA-12 alloy.
Investigation of SiO2 thin films on Si substrates for use as standards for laser-acoustic measuring devices
Authors: Lucca D. A. , Herrmann K. , Klopfstein M. J. , Menelao F.
Published: March 2022

We report on an investigation of the suitability of SiO2 thin films for use as calibration standards for the measurement of elastic modulus by laser-acoustic measuring devices. Film thicknesses for a range of thin film standards, originally developed for the calibration of ellipsometers, were obtained by X-ray reflectometry, ellipsometry, and metrological scanning force microscopy. Using the calibrated values of film thickness, a laser-acoustic method was used to obtain the elastic moduli of the thin films. Nanoindentation of the films, performed at two different laboratories was used to provide an independent measure of the elastic modulus values. The modulus values determined by nanoindentation and the laser-acoustic method were found to agree within 4.6 %, which was within the calculated uncertainty of the measurements performed. As a result of their high homogeneity with respect to film thickness and elastic modulus, their low surface roughness and the good laser-acoustic signal quality, the thin films investigated appear to hold promise as standards for laser-acoustic measuring devices.
The deformation behaviour of electrodeposited nanocrystalline Ni in an atomic force microscope with a newly developed in situ bending machine
Authors: Yang B. , Vehoff H. , Hempelmann R.
Published: March 2022

Four-point-bending and strain-controlled fatigue experiments were performed on electrodeposited nanocrystalline nickel specimens at room temperature. For the first time, the deformation behaviour of bulk nanonickel specimens was studied in an atomic force microscope with a newly developed in situ bending machine. Results show that grain boundary sliding plays an important role during deformation, and the fatigue crack propagates along grain boundaries.
Mechanism of quasi-viscous flow of zinc single crystals
Authors: Pieła Krzysztof
Published: March 2022

This paper reports the results of mechanical investigations (tensile and relaxation tests), geometrical measurements as well as macro- and microscopic (slip traces) observations of zinc single crystals in the ‘hard’ orientation (from the line [1120] – [1010] of the standard triangle) tested in the temperature range 523– 673 K. Consideration of the experimental data lead to the conclusion that the quasi-viscous flow of crystals results from localized coarse slip in the basal system occurring in the structure of uniformly distributed slip in the 1st order prismatic (and/or the 1st order pyramidal) systems. The proposed mechanism explains the high strain-rate sensitivity and the ‘jerky’ character of the flow of the crystals.
Thermodynamic investigation of Co–Cr alloys, III: Thermo-analytical measurements using DSC and DTA techniques
Authors: Sterneland Thérèse
Published: March 2022

Several Co–Cr alloys have been investigated by Differential Scanning Calorimetry (DSC) as well as by Differential Thermal Analysis (DTA) in the temperature range 298 – 1823 K. The compositional range investigated was from 0 to 87 wt.% Cr with special attention given to alloys with low Cr contents, i. e. 0 to 10 wt.% Cr. From the DSC measurements molar heat capacity values, phase transformation temperatures, enthalpies of transformation and Curie transition temperatures were derived. From the DTA measurements, the melting temperatures and melting enthalpies were evaluated. The trends obtained were compared with the results for pure Co as well as the proposed phase diagram reported in literature.
Numerical simulation and experimental analysis for evaluating warpage of a 3D thin-walled polymeric part using the injection compression molding process
Authors: Sönmez Deniz , Akdoğan Eker Ayşegül
Published: March 2022

Injection compression molding (ICM) is a nontraditional hybrid injection molding (IM) process that has been utilized to mold a wide range of the latest and difficult-to-manufacture precision parts that require high dimensional accuracy and no residual stresses. This paper introduces the accurate calculation of warpage for ICM by numerical simulation via Moldflow software, and a comparison of results with products produced experimentally by ICM. To begin with, the process parameters of ICM were discussed based on the numerical simulations. The effects of process parameters, namely melt temperature, mold temperature, compression pressure, and compression distance, on warpage behavior of a molded 3D BJ356MO polypropylene (PP) (100MFI) part were investigated using Taguchi analysis. The obtained warpage results with optimum process parameters were compared with experimental measurements to test the validity of the simulation model of ICM. It was found that the numerical simulations of the ICM show good agreement with experimental measurements.
RNN based EPON dynamic bandwidth allocation algorithm for complex network
Authors: Yu Jinxia , Fu Yanyan , Xiao Fan , Jia Huijuan , Qin Panke , Zhao Zongqu , You Junru , Liu Feiyang , Han Shangya , Wang Jiawei
Published: March 2022

In the development of ethernet passive optical networks (EPONs), quality of service (QoS) support and fairness per optical network unit (ONU) are crucial issues. However, making an elaborate analysis of the existing prediction-based bandwidth allocation algorithm, light load penalty, low prediction precision are pointed out. We present an improved dynamic bandwidth pre-allocation algorithm (R-DBA), which employs recurrent neural network (RNN) to predict the high-priority service traffic in EPON. And we introduce mixed integer linear programming (MILP) for optimally building DBA algorithm. This algorithm achieves the prediction of the high-priority service traffic by RNN during the waiting time and supports bandwidth pre-allocation, thus ensuring the fairness of the bandwidth allocation.
Medical student research opportunities: a survey of osteopathic medical schools in the United States
Authors: Hamby Tyler , Wilson Don P. , Bui Priya , Lowery Jonathan , Basha Riyaz
Published: March 2022

Context

It is important for colleges of osteopathic medicine (COMs) to provide opportunities for osteopathic medical students (OMSs) to conduct research under the guidance of professional researchers. However, COMs historically lag behind allopathic medical schools in research offerings for medical students. The literature would benefit from a synopsis of research opportunities for OMSs at COMs.

Objectives

This study aims to assess the availability of research opportunities currently offered to OMSs and to identify structured research programs (SRPs) to provide data that may help COMs expand such opportunities.

Methods

Two online surveys were developed. The General Survey asked about general research opportunities, research requirements, and SRPs, which we define as optional, intramural, and mentored research programs. The follow-up SRP Survey sought to understand the history, funding, and organizational structure of SRPs. Between February and June 2021, the General and SRP Surveys were sent to all COMs in the United States. Response data were analyzed descriptively.

Results

Responses were received from 32 (84.2%) of 38 COMs. Nearly all COMs offered research symposia, offered third- or fourth-year research elective rotations, and provided some form of funding for OMSs to participate in research. Fourteen (43.8%) COMs had mandatory research requirements. Twenty COMs (62.5%) offered 31 SRPs, and surveys were completed for 25 (80.6%) SRPs. SRPs were founded a median (range) of 7 (1–43) years prior and accommodated 20 (4–50) OMSs annually. Among the responding SRPs, 12.0% had external funding, 96.0% required applications, 50.0% interviewed applicants prior to acceptance into the program, 72.0% required OMSs to identify their own mentors, 68.0% offered stipends to OMSs, 28.0% offered course credits, 96.0% had clinical research opportunities, and 68.0% offered research-oriented didactics. In 84.0% of SRPs, OMSs worked predominantly in the summer after OMS-I; for these SRPs, students had 4–10 weeks of dedicated time for participation in research.

Conclusions

Findings from our surveys provide a synopsis of the research opportunities currently provided by COMs in the United States. Our data demonstrated wide variability of research opportunities among COMs.
Evaluation of efficacy and safety of long-acting PEGylated recombinant human growth hormone (Jintrolong) for patients with growth hormone deficiency
Authors: Du Hanze , Wu Danning , Yi Pengfei , Bai Xi , Luo Yunyun , Yang Hongbo , Chen Shi , Pan Hui , Zhu Huijuan
Published: March 2022

Objectives

This study aimed to compare the efficacy, safety and metabolic effects of once-weekly pegylated human growth hormone (PEG-rhGH) with daily rhGH in patients with growth hormone deficiency (GHD).

Design

48 patients enrolled in this 12-month single-center, open-label, prospective, randomized controlled trial is allocated to PEG-rhGH 0.12 mg/kg/w and 0.20 mg/kg/w treatment. Besides, the control group allocated 23 patients treated with daily rhGH 0.28 mg/kg/w matched with sex, age, and baseline IGF-1 levels. The primary endpoint included height velocity (HV) and IGF-1 increase at the end of treatment. Other parameters associated with growth, metabolism and safety were also monitored.

Results

In terms of HV increase, the efficacy of PEG-rhGH dosed at 0.12 mg/kg/w and 0.20 mg/kg/w was comparable to that of daily rhGH dosed at 0.28 mg/kg/w after 3, 6 and 12 treatment (p>0.05). IGF-1 concentration and IGF-1 SDS were both elevated significantly at 3, 6 and 12 months (p=0.000) into normal range following PEG-rhGH treatment. BMI SDS elevated after PEG-rhGH treatment for 3, 6 and 12 months (p=0.000). HbA1c elevated after 3 and 12 months (p=0.009) and METS-IR elevated after 6 months (p=0.019) compared with baseline. The differences of other metabolic indexes (such as blood glucose, blood lipid, etc.) have no statistical significance (p>0.05). No severe adverse event was observed among the three groups.

Conclusions

The efficacy and safety were promising and comparable between once-weekly PEG-rhGH and daily rhGH injection within 12 months. The negative influence on glucose homeostasis needed attention and monitoring.
The crystal structure bis(dimethylsulfoxide-κ1O)-dipyridine-κ1
N-bis(m2-(Z)-3-methyl-2-oxido-N-((Z)-oxido(phenyl)methylene)benzohydrazonato-κ5)trinickel(II) - dimethylsulfoxide (1/2), C48H56N6Ni3O10S4
Authors: Yang Liguo , Wang Xin , Zou Kun , Hu Shuige , Liu Xiaozhen
Published: March 2022

C48H56N6Ni3O10S4, monoclinic, P21 (no. 4), a = 12.3887(11) Å, b = 15.7405(13) Å, c = 13.4254(11) Å, β = 97.364(2)°, V = 2596.4(4) Å3, Z = 2, R

gt
(F) = 0.0530, wR

ref
(F
2) = 0.1316, T = 298 K.
Crystal structure of 2-(4-bromobenzyloxy)-6-chloropyridine, C12H9BrClNO
Authors: Lu Zhi-Qiang
Published: March 2022

C12H9BrClNO, monoclinic, P21/n (no. 14), a = 4.3665(3) Å, b = 22.5576(17) Å, c = 12.1286(10) Å, β = 99.028(7)°, V = 1179.84(16) Å3, Z = 4, R

gt
(F) = 0.0595, wR

ref
(F
2) = 0.1451, T = 293 K.