Straight Samples Research Articles

Stereotypes of White and East Asian Women and Men with Branched Attractions.

People with branched attractions may experience sexual and romantic attractions to different genders; for example, they may be sexually attracted to one gender and romantically attracted to another gender. Because branched attractions may violate folk theories about sexuality, we expected individuals with these attractions to face unique stereotypes. Across three preregistered experiments (total N = 1041), and using predominantly White, non-Latiné, and straight samples, we asked if White (Studies 1 and 2) and East Asian (Study 3) targets with branched attractions are seen as: (1) confused, dishonest, and non-monogamous (bi stereotypes), (2) uncertain about and in denial of their sexuality (instability stereotypes), and (3) desired as sexual objects (fetishized), compared to targets with aligned (same-gender, other-gender, bisexual) attractions. We also assessed warmth toward targets, and explored perceivers' need for cognition as a moderator. As expected, White and East Asian women and men with branched attractions faced heightened bi and instability stereotypes, whereas findings with warmth, fetishization, and need for cognition were mixed. Discussion considers the implications of these findings for sexually and racially minoritized individuals.

Relations Between Rape Myths, Ambivalent Sexism, Social Dominance Orientation, and Right-Wing Authoritarianism Across Gay and Straight Women and Men: More Similar Than Dissimilar

ABSTRACT Rape myths support and fuel cultural understandings regarding gender roles and deny the victim’s rights and strengthen those of the instigator. Little research exists examining the invariance of rape myths measures and models used to explain rape myths across gay and straight samples. Examining correlates of rape myths and determining if the pattern of relations between correlates is similar across gay and straight male and female samples provides insights into socially constant factors that are influencing rape myth acceptance. Participants (294 straight women, 282 gay women, 293 straight men, and 234 gay men) were asked to complete measures of social dominance orientation (SDO), right-wing authoritarianism (RWA), ambivalent sexism toward women, ambivalent sexism toward men, and rape myths toward women. We tested four models that highlighted significant, direct paths between SDO, RWA, and rape myth acceptance. Both hostile sexism toward women and benevolent sexism toward men demonstrated significant indirect effects between SDO, RWA, and rape myth acceptance. Benevolent sexism toward women and hostile sexism toward men demonstrated, in most samples, significant indirect effects between SDO, RWA, and rape myth acceptance. However, the strength of those relations differed for gay and heterosexual samples. This provides further understanding of rape myths as SDO, RWA, and benevolent and hostile sexism toward men and women play a role in supporting rape myth acceptance and establishes that, overall, these relations are more similar than dissimilar across straight and gay samples.

(009) SEXUAL FANTASY AND DESIRE DIFFER FOR PLURISEXUAL PEOPLE IN SAME-GENDER VS. MIXED-GENDER RELATIONSHIPS

Abstract Introduction In recent years there has been a surge of research on plurisexuality (the ability to experience attraction to more than one gender). Evidence strongly suggests that plurisexual people experience desire differently, face unique stressors, and have increased risk for sexual dysfunction compared to gay and lesbian groups (Björkenstam et al., 2020). These factors may differ between plurisexual people in same-gender relationships and those in mixed-gender relationships. Fantasy and desire, two fundamental constructs of sexology theory and sex therapy, merit further research in this population. Objective We hypothesize that plurisexual people experience fantasy and desire differently depending on their relationship type (same-gender vs. mixed-gender). Methods Data was collected for a larger study of sexual health and behaviors in undergraduate students at a large university in the Midwestern US. The sample included participants in relationships (n=493; mean age = 20.48 years; 80% women, 16% men, 4% gender minority; 78% White). Respondents who identified as “bisexual,” “pansexual,” “mostly heterosexual,” “mostly lesbian/gay,” or a combination of these were coded as plurisexual, and other respondents (e.g., “heterosexual,” “lesbian/gay,” “asexual”) were coded as not plurisexual. Respondents were coded as being in same-gender relationships if they identified as a man dating a man, a woman dating a woman, or any gender minority (e.g., “non-binary,” “gender fluid”) dating a man, woman, or other gender minority person (i.e., relationships likely to be perceived as queer). Respondents were coded as being in mixed-gender relationships if they identified as a man dating a woman or a woman dating a man. Fantasy was measured with an adapted Sex Fantasy Questionnaire (SFQ; Wilson, 1988), and desire with the Sexual Desire Inventory-2 (Spector, Carey, & Steinberg, 1996). We conducted two-way ANOVAs to evaluate the influence of plurisexual identity and relationship type on fantasy and desire. Results There was a significant main effect of plurisexual identity on sexual fantasy (F(1, 391)=58.61, p<0.01) and desire (F(1, 469)=7.26 p<0.01), with plurisexual participants reporting higher levels of both. There was also a significant interaction effect between plurisexual identity and relationship type for fantasy (F(1, 391)=4.73, p=0.03) and sexual desire (F(1, 469)=5.78, p=0.02), such that the effect of plurisexuality was amplified for participants in mixed-gender relationships and attenuated for participants in same-gender relationships (see Figures). Conclusions Results suggest that plurisexual people experience higher levels of fantasy and desire when in mixed-gender vs. same-gender relationships. These differences could be attributed to perceptions that plurisexual people in same-gender relationships are queer and those in mixed-gender relationships are straight (Arriaga & Parent, 2019). Additionally, the fluidity of sexual identity suggests that experiences of attraction, desire, and fantasy change substantially based on the gender of one’s partner (Diamond, 2008). Clinically, our findings point to different applications of interventions on fantasy intended to stimulate desire in plurisexual patients with low desire, address desire discrepancy between partners, or separate problematic desire from behavior. As most research surrounding fantasy and its role in desire was developed in straight cisgender samples, clinicians and researchers should consider sexual orientation, relationship type, and their interaction when intervening upon fantasy. Disclosure No.

The Effect of Laser Shock Peening (LSP) on the Surface Roughness and Fatigue Behavior of Additively Manufactured Ti-6Al-4V Alloy

Laser shock peening (LSP) uses plasma shock waves to induce compressive residual stress at the surface of a component which has the potential to improve its fatigue properties. For AM parts, the existence of internal defects, surface roughness, and tensile residual stresses leads to noticeably lower fatigue strength compared to materials produced through conventional processes. Furthermore, there is a tendency for greater scatter in the fatigue behavior of these parts when compared to traditionally manufactured components. In this study, the effect of LSP on the roughness and fatigue behavior of Ti-6Al-4V alloy constructed through Laser Powder Bed Fusion (L-PBF) technique was investigated. Two types of samples were designed and tested: as-built surface air foil samples for four-point bending tests and machined surface straight gage samples for uniaxial fatigue testing. Two sets of process parameters, optimized and non-optimized, were also used for the fabrication of each sample type. It was found that LSP had negative effects on the smooth (i.e., machined) surface samples, whereas for as-built surfaces the roughness was enhanced by decreasing the sharpness of the deep valleys and partially remelting the loosely bonded particles on the peaks. It was found that the scatter of the fatigue data decreased for optimized machined samples, while no clear improvement was observed in their lives. However, all non-optimized samples showed improvements in fatigue lives after the LSP process.

Pull-out behaviour of steel fibres embedded in ultra-high-performance concrete after exposure to high temperatures

The paper examined the bond-slip behaviour of steel fibres embedded in ultra-high-performance concrete (UHPC) after exposure to elevated temperatures. Different types of steel fibres were cast into the halved UHPC dog-bone-shaped samples, including straight fibres, three types of hooked-end fibres and corrugated fibres. The bond response was investigated through single fibre pull-out tests on the samples unheated and heated to 200, 400 and 600 °C. In addition, the effects of polypropylene (PP) fibre addition and heating rate on steel fibre’s bond behaviour were also investigated. The results revealed an increase in bond strength when the straight and hooked-end fibre samples were heated to 200 °C, while the bond strength of the corrugated fibre decreased at the same temperature. Bond strength reductions were observed at higher temperatures. In addition, the straight fibres led to the lowest pull-out resistance as both the hooked-end and the corrugated fibres significantly enhanced the bond strength. With the hooked-end or corrugated fibres, the failure mode gradually shifted from pull-out failure to fibre rupture. Besides, adding PP fibres increased the bond strength of straight fibres at 400 °C but reduced the bond strengths of hooked-end fibres at ambient and high temperatures. High heating rate also led to a greater bond strength for the straight fibres at 200 °C and 400 °C.

Aluminium-Stabilized High-Temperature Superconducting Cable for Particle Detector Magnets

Within the context of EP R&D, CERN is developing a high-temperature superconducting (HTS) conductor for future superconducting detector magnet projects. The conductor features a Rare-Earth Barium Copper Oxide (REBCO) tapes soldered to a copper-coated high-purity aluminium stabilizer. Critical currents of the 200 mm long straight cable samples measured with various numbers of REBCO tapes at 77 K are consistent with empirical scaling formulas for critical current within 10%. A few percent deviations are expected to arise from the critical current variation along the length of the HTS tape. No degradation was observed after multiple soldering and de-soldering cycles at 165 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^\mathrm{o}$</tex-math></inline-formula> C with Bi–Sn based solder and after thermal cycling between 77 K and room temperature. However, extreme bending (of 100 mm radius) of the already soldered HTS cable leads to failure of the cable. We repeated the critical current measurements with a 650 mm long cable loop sample with 85 mm bending radius, where the HTS tapes were soldered after the aluminium profile was bent. The critical current of the HTS cable loop was 7% lower than the prediction. Based on the first critical current measurements, the HTS cable preparation method presented in this work results in repeatable quality aluminium-stabilized HTS cable.

Conceptual Design Study of a Test Facility Magnet for Fusion Conductor Samples

Design studies of the steady-state Korean fusion demonstration reactor (K-DEMO) magnet system have been conducted since 2013. The maximum magnetic field of the K-DEMO toroidal field (TF) coil is expected to be over 16 T. A high field superconducting magnet and a facility for testing the K-DEMO TF conductor samples are also being designed to prepare for the development of the K-DEMO TF conductor. To test straight fusion conductor samples compatible with the K-DEMO TF conductor, it is essential to have a large, 150 mm wide by 120 mm high sample space in the magnet. The required maximum magnetic field of the fusion conductor test magnet is expected to be over 15 T. The field consists of about a 15 T background field and some self-field. Both high current density Nb <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> Sn strands and high temperature superconductor (HTS) tapes are candidates for the superconducting materials for the magnet. In this work, two conceptual design study models of the high field magnet are introduced - a planar racetrack dipole based on HTS tape (I <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> > 200 A/4-mm at 4.2 K, 18 T) cable-in-conduit conductor (CICC), and a non-planar flared end saddle dipole based on Nb <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> Sn strand (J <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> > 2600 A/mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> at 4.2 K, 12 T) CICC. 2-dimensional magnetic and mechanical analyses of both magnet models were performed and the main features of the models are presented.

Chemical variations in tension wood of poplar tree induced by intermittent bending, fertilizer and hormone treatments

Tree growth is influenced by various environmental factors that lead to anatomical, physical and chemical changes in their wood. Reaction wood is one of the tree's reactions that make many restrictions in wood usages. Reaction wood in broadleaf is called tension wood. This study was aimed to stimulate the formation of tension wood in two-year-old seedlings of Populus alba by using intermittent bending, nitrogen fertilization and gibberellin hormone. The application of different treatments increased the content of cellulose compared to the control sample. Meanwhile, the bent specimens had more increase while the straight specimens had no significant difference in the statistical grouping. The content of lignin decreased in all treatments compared to the control sample. The cellulose/lignin ratios obtained from ATR-FTIR (Attenuated Total Reflectance-Fourier Transform Infrared) analysis of wood sawdust and chemical composition measurements were almost close to each other and were higher in the treated samples than in the control. The degree of crystallinity obtained from XRD (X-ray Diffraction) measurements showed that all samples under intermittent bending had a significantly higher degree of crystallinity than the control sample, while this increase was not significant in all straight samples compared to the control sample. In general, it can be concluded that intermittent bending treatment had a greater effect on the stimulation and changes of chemical properties of tension wood in poplar and the application of nitrogen fertilization and gibberellin hormone increased this effect. The formation of gelatinous layer in the innermost part of the intermittent bent seedlings fiber cell wall was visible in light microscope images.

Collaborative Robotic Wire + Arc Additive Manufacture and Sensor-Enabled In-Process Ultrasonic Non-Destructive Evaluation.

The demand for cost-efficient manufacturing of complex metal components has driven research for metal Additive Manufacturing (AM) such as Wire + Arc Additive Manufacturing (WAAM). WAAM enables automated, time- and material-efficient manufacturing of metal parts. To strengthen these benefits, the demand for robotically deployed in-process Non-Destructive Evaluation (NDE) has risen, aiming to replace current manually deployed inspection techniques after completion of the part. This work presents a synchronized multi-robot WAAM and NDE cell aiming to achieve (1) defect detection in-process, (2) enable possible in-process repair and (3) prevent costly scrappage or rework of completed defective builds. The deployment of the NDE during a deposition process is achieved through real-time position control of robots based on sensor input. A novel high-temperature capable, dry-coupled phased array ultrasound transducer (PAUT) roller-probe device is used for the NDE inspection. The dry-coupled sensor is tailored for coupling with an as-built high-temperature WAAM surface at an applied force and speed. The demonstration of the novel ultrasound in-process defect detection approach, presented in this paper, was performed on a titanium WAAM straight sample containing an intentionally embedded tungsten tube reflectors with an internal diameter of 1.0 mm. The ultrasound data were acquired after a pre-specified layer, in-process, employing the Full Matrix Capture (FMC) technique for subsequent post-processing using the adaptive Total Focusing Method (TFM) imaging algorithm assisted by a surface reconstruction algorithm based on the Synthetic Aperture Focusing Technique (SAFT). The presented results show a sufficient signal-to-noise ratio. Therefore, a potential for early defect detection is achieved, directly strengthening the benefits of the AM process by enabling a possible in-process repair.

Distensibility of Deformable Aortic Replicas Assessed by an Integrated In-Vitro and In-Silico Approach.

The correct estimation of the distensibility of deformable aorta replicas is a challenging issue, in particular when its local characterization is necessary. We propose a combined in-vitro and in-silico approach to face this problem. First, we tested an aortic silicone arch in a pulse-duplicator analyzing its dynamics under physiological working conditions. The aortic flow rate and pressure were measured by a flow meter at the inlet and two probes placed along the arch, respectively. Video imaging analysis allowed us to estimate the outer diameter of the aorta in some sections in time. Second, we replicated the in-vitro experiment through a Fluid-Structure Interaction simulation. Observed and computed values of pressures and variations in aorta diameters, during the cardiac cycle, were compared. Results were considered satisfactory enough to suggest that the estimation of local distensibility from in-silico tests is reliable, thus overcoming intrinsic experimental limitations. The aortic distensibility (AD) is found to vary significantly along the phantom by ranging from 3.0 × 10−3 mmHg−1 in the ascending and descending tracts to 4.2 × 10−3 mmHg−1 in the middle of the aortic arch. Interestingly, the above values underestimate the AD obtained in preliminary tests carried out on straight cylindrical samples made with the same material of the present phantom. Hence, the current results suggest that AD should be directly evaluated on the replica rather than on the samples of the adopted material. Moreover, tests should be suitably designed to estimate the local rather than only the global distensibility.

Picosecond Laser Cutting-Assisted Rapid Laser Reactive Sintering for the Fabrication of Crack-Free Protonic Ceramic Electrochemical Cells

Nowadays, greenhouse gas emissions have become a more severe problem. Renewable energy sources are crucial to solve this problem. Protonic ceramic fuel cells (PCFCs) have been considered ideal for energy conversion and storage applications. Compared to oxide-ion, proton, as the charge carrier, has a much lower transport activation energy. This property leads to the wide application of protonic ceramics in intermediate-temperature electrochemical devices [1]. However, the refractory property of typical protonic ceramics makes the conventional furnace sintering methods for PCFCs ineffective and time-consuming. The rapid laser reactive sintering (RLRS), with the assistance of sintering aids, has shown its ability to sinter protonic ceramics in a short time (< 10 s) from cost-effective raw materials of oxides and carbonates. We have successfully demonstrated the feasibility of preparing crack-free BaCe0.7Zr0.1Y0.1Yb0.1O3-δ (BCZYYb) electrolyte samples by RLRS [2]. However, it is not easy to achieve crack-free samples with a large area. Therefore, eliminating the cracks during sintering is key to sinter large area samples.In the process of RLRS, the protonic ceramic experiences significant thermal stress. The cracks introduced by thermal stress originated from both sides of the straight stripe-shaped samples and propagated into the center area. In this work, we fabricated PCFC half cells using the RLRS method. In the half cell, we chose the 40wt% BCZYYb+60wt% NiO and BCZYYb as anode and electrolyte, respectively. The anode was 3D printed with 80mm in length, 15mm in width, and 200-300μm in thickness. The electrolyte was spray-coated on the anode surface. 1.0wt% of NiO added to the electrolyte served as the sintering aid. As mentioned before, during RLRS, the cracks originate from both sides of the samples. Because of the contact angle of the slurry on the substrate, both sides of the rectangular half cells have thickness variance, and this kind of inconsistency caused stress concentration. We utilized a picosecond laser to cut both sides of the samples. Besides, the thermal effect of picosecond laser can sinter a small area to provide compressive stress to the bulk of the sample due to sintering shrinkage. The cut samples with a reduced width of 11mm were then sintered using CO2 laser in a scanning manner. A sample with a length of 80mm and a width of 11mm was prepared successfully. The combination of picosecond laser cutting and RLRS enabled us to manufacture large area crack-free co-sintered BCZYYB half cells quickly. Keywords: 3D printing, Laser sintering, Reactive sintering, Picosecond laser, Protonic ceramic fuel cell. References Mu, S., Zhao, Z., Huang, H., Lei, J., Peng, F., Xiao, H., & Brinkman, K. S. (2020). Advanced Manufacturing of Intermediate-Temperature Protonic Ceramic Electrochemical Cells. The Electrochemical Society Interface, 29(4), 67.Mu, S., Zhao, Z., Lei, J., Hong, Y., Hong, T., Jiang, D., ... & Tong, J. (2018). Engineering of microstructures of protonic ceramics by a novel rapid laser reactive sintering for ceramic energy conversion devices. Solid State Ionics, 320, 369.

Effect of Alloying Powders on Microstructure and Mechanical Properties of Aluminum Alloy Arc Additive Manufacturing.

Cold metal transfer arc additive manufacturing technique was used to produce 5356 aluminum alloy by adding refining agents to solve the problems of coarse grains and poor performance. Metallic powders (Ti, TiH, and Ti+B4C) were used to refine the grain size and promote the mechanical properties of the alloy. The effects of refining agents on the microstructure and mechanical properties of straight wall samples (SWSs) were studied. Samples with Ti+B4C addition had a profound impact on morphology. However, the TiH added sample revealed uneven transition between sediment layers, unstable precipitation process, unstable wall height and wall width, poor morphology, and defects. All SWSs with powder addition revealed the formation of the Al3Ti phase. Moreover, the columnar grains between the layers were transformed into equiaxed grains and finer grains at the center of the layers. There was a significant effect of TiH on the grain refinement. The samples with Ti demonstrated superior mechanical properties. The tensile strength and elongation of the SWSs increased by 28 MPa and 4.6% in the parallel additive direction and by 37 MPa and 8.9% in the vertical direction. The addition of Ti also contributed to the even distribution of the mechanical properties in both directions.

Effect of Cooling Method on Formability of Laser Cladding IN718 Alloy.

The finite element model (FE) of temperature field of straight thin-walled samples in laser cladding IN718 was established, and the growth of microstructure was simulated by cellular automata (CA) method through macro-micro coupling (CA-FE). The effects of different cooling conditions on microstructure, hardness, and properties of laser-cladding layer were studied by designing cooling device. The results show that the simulation results are in good agreement with the microstructure of the cladding layer observed by the experiment. With the scanning strategy of reducing laser power layer-by-layer, the addition of water cooling device and the processing condition of 0.7 mm Z-axis lift, excellent thin-walled parts can be obtained. With the increase of cladding layers, the pool volume increases, the temperature value increases, the temperature gradient, cooling rate, solidification rate, K value gradually decrease, and eventually tend to be stable, in addition, the hardness shows a fluctuating downward trend. Under the processing conditions of layer-by-layer power reduction and water cooling device, the primary dendrite arm spacing reduced to about 8.3 μm, and the average hardness at the bottom of cladding layer increased from 260 HV to 288 HV. The yield strength and tensile strength of the tensile parts prepared under forced water cooling increased to a certain extent, while the elongation slightly decreased.

Sexual Orientation Beliefs and Identity Development: A Person-Centered Analysis among Sexual Minorities

ABSTRACT We conducted person-centered analysis of sexual orientation beliefs among sexual minorities to explore potential relationships between these beliefs and sexual orientation, developmental milestones, race and ethnicity, and attitudes about sexual orientation. We recruited participants (N = 416) via Amazon Mechanical Turk who completed measures of beliefs about sexual orientation and attitudes about their own sexuality, as well as assessments of mental health and age of sexual identity development milestones. We conducted a latent profile analysis and found three distinct sexual orientation belief profiles, similar to those previously observed in predominantly straight samples. We found that sexual orientation and race-ethnicity predicted belief profile membership, with the latter exhibiting the most substantial effect. Of the four identity developmental milestones tested, only the age of first same-sex attraction predicted belief profile membership. Across profiles, members differed significantly in their mean endorsement of both positive and negative attitudes regarding sexual orientation and psychological distress. Thus, the current research suggests that sexual orientation beliefs are powerful constructs in the lives of sexual minorities, with relationships to sexual orientation, other social identities, and mental health.

Influence of Wheat Flour Milling Yield on Physicochemical, Microbial, and Antioxidant Properties of Korea Wheat (Triticum aestivum L. var. Jokyoung)

The physicochemical, microbial, and antioxidant properties of a Korean wheat variety (Jokyoung) were measured according to milling yield (60–90%) by adding fractions from millstreams. As the milling yield increased, the wheat flour showed low quality on physicochemical properties in general. Significant differences in proximate analysis, color, solvent retention capacity, pasting property, and antioxidant activity were observed as the yield increased to maximize the production of wheat flour from wheat kernels. Adding clear flour and shorts did not significantly affect the quality of the wheat flour in comparison with straight flour samples. However, as brans were added to the flour portion, the wheat flour quality parameters decreased significantly in color, solvent retention capacity, and pasting properties. On the other hand, antioxidant properties increased as brans were added. Maximizing wheat flour yield is a key to minimizing the production cost of Korean wheat flour, which is approximately three times more expensive than imported wheat flour. Adding clear flour and a certain portion of shorts did not seem to significantly influence the overall quality of wheat flour from Korean domestic wheat variety.

Mechanical and Electro-Mechanical Investigations of Assembled HTS CroCo Triplets

In fusion applications, cables are exposed to high currents and magnetic fields. Cable-in-conduit conductors (CICC) made of several high temperature superconductor (HTS) strands, like the HTS CrossConductor (HTS CroCo), have the ability to meet these requirements. HTS CroCos are made of a cross-shaped stack consisting of two different widths of REBCO and copper tapes embedded in a round solder matrix. The round outer shape allows an easy encapsulation with copper tubes for electrical and mechanical reasons. The triplet-CICC of HTS CroCos is considered as the next step towards a full size fusion conductor. First, a straight triplet sample and later a high field winding demonstrator is planned to be tested at high operational currents (>10 kA) and high magnetic fields (>10 T). Operating the triplet under such conditions will inevitably lead to high Lorentz forces acting on the strands of the triplet-CICC. In order to investigate the electromechanical performance of HTS CroCo triplets, short triplet samples were loaded with transversal mechanical pressure at 77 Kelvin, self-field, to simulate the Lorentz forces of the intended high-current, high-field application. The maximum allowable transversal load was investigated for different triplet configurations in order to determine design limits for the triplet winding demonstrator.

Process to densify Bi2Sr2CaCu2OX round wire with overpressure before coil winding and final overpressure heat treatment

Overpressure (OP) processing of wind-and-react Bi2Sr2CaCu2Ox (2212) round wire compresses the wire to almost full density, decreasing its diameter by about 4% without change in wire length and substantially raising its JC. However, such shrinkage can degrade coil winding pack density and magnetic field homogeneity. To address this issue, we here present an overpressure predensification (OP-PD) heat treatment process performed before melting the 2212, which greatly reduces wire diameter shrinkage during the full OP heat treatment (OP-HT). We found that about 80% of the total wire diameter shrinkage occurs during the 50 atm OP-PD before melting. We successfully wound such pre-densified 1.2 mm diameter wires onto coil mandrels as small as 10 mm diameter for Ag–Mg-sheathed wire and 5 mm for Ag-sheathed wire, even though such small diameters impose plastic strains up to 12% on the conductor. A further ∼20% shrinkage occurred during a standard OP-HT. No 2212 leakage was observed for coil diameters as small as 20 mm for Ag–Mg-sheathed wire and 10 mm for Ag-sheathed wire, and no JC degradation was observed on straight samples and 30 mm diameter coils.

Melt pool boundary extraction and its width prediction from infrared images in selective laser melting

Selective laser melting (SLM) involves periodic processes of rapid temperature rise and drop, so it is of great interest in evaluating the quality of the melted powders by real-time thermal information. In this study, a LumaSense MCS640 thermal imaging camera in coaxial system, which can track the location of melt pool, was used to real-time monitor the surface temperature during Ti-6Al-4V forming and predict an average melt width by extracting the boundary of the melt pool in each infrared image. The characteristics of the temperature gradient distribution around a melt pool instead of the temperature itself was analyzed, the boundary of a melt pool was determined then by the maximum (or minimum) temperature gradient point in space. Straight melt samples were obtained by a fixed laser scanning direction in this study, the extracted boundaries of the moving melt pool in the direction perpendicular to the laser scanning direction were compared with the measured melt width from a microscope. A best width divergency between the prediction and measurement around 5% is achieved.

Experimental Test and Analysis of AC Losses in Multifilamentary MgB2 Wire

AC losses in superconductors are essential for the design of cooling system for large scale power applications. Magnesium diboride (MgB2) superconducting wires have been investigated and manufactured over the last decade due to cheap raw materials and flexibility for coil design. In addition, multifilamentary MgB2 wires have been manufactured to reduce ac losses. In this paper, self-field ac losses of multifilamentary MgB2 wires with magnetic barrier are investigated using both experimental and numerical methods. A short straight wire sample and a coil sample are tested under various temperatures and frequencies between 16- and 128-Hz. The test results show that the transportation loss is independent of the operating temperature. On basis of both theoretical and numerical study, it is found that hysteresis loss in superconductor accounts only for a small fraction of the transportation losses, ferromagnetic hysteresis loss in the magnetic barrier dominates when the transport current is low, whereas eddy current loss dominates when the transport current is close to the critical current.

Investigating the Accuracy, Precision, and Cooling Rate Dependence of Laboratory‐Acquired Thermal Remanences During Paleointensity Experiments

AbstractWe examine the behavior of natural basaltic and trachytic samples during paleointensity experiments on both the original and laboratory‐acquired thermal remanences and characterize the samples using proxies for domain state including curvature (k) and the bulk domain stability parameters of Paterson (2011,https://doi.org/10.1029/2011JB008369) and Paterson et al. (2017,https://doi.org/10.1073/pnas.1714047114), respectively. A curvature value of 0.164 (suggested by Paterson, 2011,https://doi.org/10.1029/2011JB008369) as a critical threshold that separates single‐domain‐like remanences from multidomain‐like remanances on the original paleointensity data was used to separate samples into “straight” (single‐domain‐like) and “curved” (multidomain‐like) groups. Specimens from the two sample sets were given a “fresh” thermal remanent magnetization in a 70 μT field and subjected to an infield‐zerofield, zerofield‐infield (IZZI)‐type (Yu et al., 2004,https://doi.org/10.1029/2003GC000630) paleointensity experiment. The straight sample set recovered the laboratory field with high precision while the curved set had much more scattered results (70.5 ± 1.5 and 71.9 ± 5.2 μT, respectively). The average intensity of both sets for straight and curved was quite close to the laboratory field of 70 μT, however, suggesting that if experiments contain a sufficient number of specimens, there does not seem to be a large bias in the field estimate. We found that the dependence of the laboratory thermal remanent magnetization on cooling rate was significant in most samples and did not depend on domain states inferred from proxies based on hysteresis measurements and should be estimated for all samples whose cooling rates differ from that used in the laboratory.