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Background: Only a few studies directly compared the therapeutic efficacy and safety of two pressurized metered-dose inhalers (pMDIs) in asthma. We analyzed the asthma treatment outcomes, safety, and patient preferences using formoterol/beclomethasone (FORM/BDP), a pMDI with extra-fine particles, compared with formoterol/budesonide (FORM/BUD), another pMDI with non-extra-fine particles.Methods: In this randomized, double-blind, double-dummy parallel group study, 40 adult asthmatics were randomized to FORM/BDP group (n=18; active FORM/BDP and placebo FORM/BUD) or FORM/BUD group (n=22; active FORM/BUD and placebo FORM/BDP). During the two visits (baseline and end of 8-week treatment), subjects were asked to answer questionnaires including asthma control test (ACT), asthma control questionnaires (ACQ), and Quality of Life Questionnaire for Adult Korean Asthmatics (QLQAKA). Lung function, compliance with inhaler, and inhaler-handling skills were also assessed.Results: Ten subjects in the FORM/BDP group and 14 in the FORM/BUD group completed follow-up visits. ACT, ACQ, QLQAKA (a primary outcome), and adverse events did not differ between two groups. We found that the increase in forced expiratory volume in 1 second/forced vital capacity and forced expiratory flow at 25% to 75% of the pulmonary volume in the FORM/BDP group was higher than in the FORM/BUD group. Regarding preference, subjects responded that the flume velocity of FORM/BDP was higher, but more adequate than that of FORM/BUD. They also answered that FORM/BDP reached the trachea and bronchus and irritated them significantly more than FORM/BUD.Conclusion: The use of pMDI with extra-fine particles may relieve small airway obstruction more than the one with non-extra-fine particles despite no significant differences in overall treatment outcomes. Some asthmatics have a misconception about the adequacy of high flume velocity of pMDIs.

Multi-component (TiZrHf)50Ni24.5Co10Cu14.5Sn1, (TiZrHf)50Ni24Co10Cu14Sn2, and (TiZrHf)50Ni23.5Co10Cu13.5Sn3 high entropy shape memory alloys (HESMAs) were prepared in this study, and the microstructures, transformation temperatures (TTs), and superelasticity were investigated through scanning electron microscopy, differential scanning calorimetry, and dynamic mechanical analysis in the tensile mode, respectively. The microstructure of the solution-treated TiZrHfNiCoCuSn HESMA specimens consisted of the matrix, (TiZrHf)2(NiCoCuSn)-type and (TiZrHf)5(NiCoCuSn)3-type second phases. The TTs of the solution-treated specimens increased with the addition of a 1 at.% of Sn content and then decreased with an additional increase in the Sn content. The (TiZrHf)50Ni24Co10Cu14Sn2 HESMAs exhibited clear superelasticity, and their total recovery strain was 2.2%.

Owing to the speculated price hike and scarcity of lithium resources, sodium-ion batteries are attracting significant research interest these days. However, sodium-ion battery anodes do not deliver good electrochemical performance, particularly rate performance. Herein, we report the facile electrospinning synthesis of a free-standing nickel disulfide (NiS2) embedded on carbon nanofiber. This electrode did not require a conducting agent, current collector, and binder, and typically delivered high capacity and rate performance. The electrode delivered a high initial capacity of 603 mAh g−1 at the current density of 500 mA g−1. Moreover, the electrode delivered the capacity of 271 mAh g−1 at the high current density of 15 A g−1. The excellent rate performance and high coulombic efficiency of the electrode were attributed to its low charge transfer resistance and unique structure.

The effect of thermal cycling on the transformation behavior of a Ti–24Nb–1Mo alloy was investigated by means of electrical resistivity measurement, transmission electron microscopy (TEM), X-ray diffraction (XRD), tensile test and Vickers hardness tests. Electrical resistivity changes were not observed in all alloys. It indicates that thermally induced martensitic transformation does not take place in the alloys. After thermal cycling between 298 K and 77 K, clear X-ray diffraction peaks corresponding to ωath phase, which did not exist before thermal cycling, were observed. Volume fraction of ωath phase increased as increasing the number of thermal cycling. ωath phase formed during thermal cycling increased hardness of the alloy. Although thermally induced martensitic transformation did not occur in the alloys, superelastic deformation behavior was observed in the alloys. The superelastic recovery ratio decreased from 81% to 41% by increasing the number of thermal cycling, which came from the increase in the volume fraction of ωath phase.

In this study, we demonstrate a simple and effective way to fabricate functionally graded TiNi-based alloys with linear variations of composition and martensitic transformation behavior. Ti50Ni50 and Ti50Ni35Cu15 alloy strips were fabricated through a melt overflow process. The compositionally graded diffusion couple was fabricated by annealing two strips of different alloy compositions after being placed face to face in a pressing graphite mold. The mechanical properties and martensitic transformation behaviour of the diffusion couple were analysed by tensile test and DSC. The compositionally graded specimens exhibited unique superelastic property and wide martensitic formation temperature range. Such mechanical and thermal behaviors of the compositionally graded TiNi-based alloy offer good function and controllability for actuators.

The effect of annealing temperature and external stress on the thermal expansion of a Ti–23Nb–0.7Ta–2Zr alloy were investigated by means of thermal expansion tests under constant load and X-ray diffraction (XRD). Negative thermal expansion (NTE), which is a shrinkage during heating, was observed in both a cold rolled and annealed specimens. The intensity of (200)β peak decreased while that of (211)β peak increased as the annealing temperature increased. The difference in expansion rate between 50 °C and 250 °C is found to decrease with an increasing annealing temperature from 600 °C to 800 °C, above which it kept almost constant. The expansion rate decreased as the applied stress increased.

Ti–18Zr–xNb–2Sn (x = 10, 11, 11.5, 12, 12.5) (at.%) shape memory alloys were fabricated by arc melting then phase constitutions and superelastic properties were investigated by X-ray diffraction (XRD) and tensile test at various temperatures between 178 K and 413 K. Excellent superelasticity was observed in 12.5Nb alloy at temperatures between 258 K and 298 K. Both superelasticity and shape memory effect were observed in 12Nb alloy at temperatures between 233 K and 383 K. Only shape memory effect was observed in 11Nb and 11.5Nb alloys at temperatures between 298 K and 383 K. 12.5Nb and 12Nb alloys consisted of the main β phase and athermal ω. The amount of β phase decreased with increasing Nb content. 10Nb alloy consisted of main α″ martensite and a small amount of β phase. The Ms temperature measured from the Clausius–Clapeyron relationship decreased greatly with increasing Nb content (100 K/at.% Nb) in these Ti–Zr–Nb–Sn alloys.

In present paper we will show how nitrogen effects microstructures, transformation temperatures, and mechanical properties of equiatomic Ti50–Ni50 and Ti-rich Ti51–Ni49 binary shape memory alloys. 0.5 at.% of nitrogen was added to prepare Ti50–Ni49.5–N0.5, and Ti51–Ni48.5–N0.5 (at.%) alloys by arc-melting. Microstructures were investigated by scanning electron microscope (SEM), phase constitutions were investigated by X-ray diffraction (XRD), transformation temperatures were investigated by differential scanning calorimeter (DSC) and mechanical properties were tested by tensile tests. Solutions treated Ti–Ni–N shape memory alloys contain TiNi matrix without nitrogen, Ti2Ni type phase containing a small amount of nitrogen and a new Ti2N type phase containing a small amount of nickel. Compared with Ti50–Ni50 and Ti51–Ni49 binary alloys, the martensitic transformation starts temperatures (Ms) of Ti50–Ni49.5–N0.5 and Ti51–Ni48.5–N0.5 ternary alloys decreased from 63.4 °C to 41.6 °C and from 85.3 °C to 79.4 °C, respectively. By adding N, fracture strain decreased and incomplete superelasticity was observed.

Ti–xNi–12Cu (at%) (x = 39, 40) alloys were prepared and then their transformation behavior and microstructures were investigated after solution treatment at various temperatures by means of scanning electron microscopy, energy dispersive X-ray spectroscopy, and differential scanning calorimetry. Matrix (B2), Ti2 (Ni, Cu) and Ti(Ni, Cu)2 phases were observed in all specimens except the TiNi39Cu12 alloy solution treated at 1373 K in which matrix (B2) and Ti2 (Ni, Cu) were observed. Volume fraction of Ti(Ni, Cu)2 phase decreased with increasing solution treatment temperature. All specimens showed the B2–B19 martensitic transformation behavior. Transformation temperatures and hysteresis decreased with increasing solution treatment temperature, which was ascribed to the decrease in the volume fraction of Ti(Ni, Cu)2 phase resulting in the increase in Ni content of matrix.

Owing to the speculated price hike and scarcity of lithium resources, sodium-ion batteries are attracting significant research interest these days. However, sodium-ion battery anodes do not deliver good electrochemical performance, particularly rate performance. Herein, we report the facile electrospinning synthesis of a free-standing nickel disulfide (NiS²) embedded on carbon nanofiber. This electrode did not require a conducting agent, current collector, and binder, and typically delivered high capacity and rate performance. The electrode delivered a high initial capacity of 603 mAh g

Electrochemical anodization of Ti–Ni alloys with different Ni composition was carried out in an ethylene glycol base electrolyte under the various conditions to investigate the effect of crystal structure and chemical composition of the Ti–Ni alloy. X-ray diffraction patterns indicated that Ti-48.0 Ni and Ti-49.0Ni alloys were the martensitic phase at room temperature, while Ti 50.6Ni and 51.0Ni were the austenitic phase. Self-organized nanotubular oxide layers were formed on four Ti–Ni alloys. The thickness of oxide layers increased with increasing anodization time and applied voltages. Energy-dispersive X-ray analysis indicated that the nanotubular oxide layers consist of two kinds of oxides, one of which is Titanium oxide and the other is Nickel oxide. These results indicate that the growth of nanotubular oxide layer formed Ti–Ni alloys are not affected by crystal structure, but by applied voltage and anodization time.

The strong 001 β 110 > β recrystallization texture is known in favor of improving superelastic recovery strain in the biomedical nickel-free Ti–Zr–Nb–Sn shape memory alloys (SMAs) experienced severely cold-rolling followed by annealing. Whereas the severe cold rolling yielded thin ribbon-like sheets which probably have low practical applications for the fabrication of medical devices although they have excellent superelasticity. In this study, Ti–Zr–Nb–Sn SMA fibers with different Nb contents were directly prepared by rapidly solidifying the molten ingot and compared with the referenced alloy sheet in terms of their texture characteristics and superelastic properties. The superelastic SMA fibers have been shown to have a great potential for manufacturing fibrous structure-based plates or scaffolds for biomedical applications. The superelasticity of the rapidly solidified Ti–18Zr‒12.5Nb–2Sn (at.%) SMA fiber specimen was observed in a wide temperature window of 100 °C, ranging from ‒ 65 °C to 35 °C. The increase of 1 at.%‒Nb was first reported to decrease the A s and A f of the Ti–Zr–Nb–Sn SMA sheet specimens by 89 °C and 95 °C, respectively. The high-resolution transmission electron microscope (HRTEM) observations revealed that athermal ω phases and nanodomains were formed in the β matrix in the Ti–18Zr‒12.5Nb–2Sn (at.%) SMA fiber specimen. Unlike the referenced bulk sheet showing 001 β 110 > β recrystallization texture, the rapidly solidified SMA fiber specimen was found to have a main texture close to ( 334 ) β [ 3 ‾ 5 ‾ 6 ] β by using electron backscatter diffraction (EBSD). A recovery strain of 5.1% was obtained in the SMA fiber specimen at a pre-strain of 5.5%. The present rapid solidified Ti–Zr–Nb–Sn SMA fibers will be of considerable applications in manufacturing superelastic porous scaffolds for bone repair.

Ti-(50-x)Ni-xSi (at%) (x = 0.5, 1.0, 3.0, 5.0) alloy ribbons were prepared via melt spinning and their crystallization procedure and transformation behavior were investigated using differential scanning calorimtry, X-ray diffraction, and transmission electron microscopy. Ti-Ni-Si alloy ribbons with Si content less than 1.0 at% were crystalline, whereas those with Si content more than 3.0 at% were amorphous. Crystallization occurred in the sequence of amorphous →B2 → B2 → Ti5Si4 + TiNi3 → B2 + Ti5Si4 + TiNi3 + TiSi in the Ti-47.0Ni-3.0Si alloy and amorphous →R → R + Ti5Si4 + TiNi3 → R + Ti5Si4 + TiNi3 + TiSi in the Ti-45.0Ni-5.0Si alloy. The activation energy for crystallization was 189 ±8.6 kJ/mol for the Ti-47Ni-3Si alloy and 212±8.6 kJ/mol for the Ti-45Ni-5Si alloy. One-stage B2-R transformation behavior was observed in Ti-49.5Ni-0.5Si, Ti-49.0Ni-1.0Si, and Ti-47.0Ni- 3.0Si alloy ribbons after heating to various temperatures in the range of 873 K to 1073 K. In the Ti-45.0Ni-5.0Si alloy, one-stage B2-R transformation occurred after heating to 893 K, two-stage B2-R-B19' occurred after heating to 973 K, and two-stage B2-R-B19' occurred on cooling and one-stage B19'-B2 occurred on heating, after heating to 1073 K.

This study investigated the pull-out resistance of superelastic shape memory alloy (SMA) short fibers in mortar with consideration of various end-anchorages that provide different anchoring actions. For the purpose, four types of SMA fibers were prepared using NiTi SMA wires with a diameter of 1.0 mm and the following four end shapes: straight (ST), L-shaped (LS), N-shaped (NS), and spearhead-shaped (SH). The straight-ended fiber was a reference with no working on the end, and the fiber with the spearhead-shaped end was crimped to make the end part flat. The fibers with L- and N-shaped ends were bent with single or double bending. The results showed that only the spearhead-shaped fibers showed self-centering behavior because of the superelasticity of the SMA after slip occurred. This paper discusses the reasons that the ST, LS, and NS fibers do not show self-centering behavior and proposes a concept to induce superelastic behavior in SMA fibers in mortar or concrete.

Ti-50.3Ni-0.7Ag (at.%) scaffolds were prepared by sintering of rapidly solidified alloy fibers. The sintered scaffolds possessed high porosity of 80% and large pores of 150–600 μm in size. The yield strength of the scaffold after annealed at 723 K for 3.6 ks was about 2.4 MPa. Ti-Ni-Ag scaffolds had an elastic modulus of 0.8 GPa, similar to that of spongy bone, and exhibited good superelasticity with total recovery strain of 3.4% when 4% pre-strain was loaded at human body temperature. Stable superelastic behavior with complete shape recovery was observed during cyclic deformation in scaffolds.

Patterned Si film electrodes with trench structured Cu current collector were fabricated by using a facile approach. Ribbon-like Si films were embedded in the trench with 28 μm in trench height. The structural and electrochemical characteristics of the patterned electrodes were investigated after annealing at 200, 300 and 400 °C. For the as-deposited Si film, the Si film consisted of Si clusters at the bottom of trenches. With increasing annealing temperature, the Cu3Si phase was formed at 300 °C and came to the surface of the film electrode through boundaries of Si clusters, and then the coarsened Cu3Si phase covered the Si clusters at 400 °C. The best electrochemical performance was obtained from the 400 °C-annealed Si film electrode due to synergy effects of the formations of the Cu3Si layer and trench structure, which could suppress the Si volume change during repeated electrochemical reactions.

The Bohai Rim Economic Circle (BREC) is an emerging economic area that has been developing rapidly and has benefited from support from the Chinese government; however, due to the unique geographic location and the late start of development, the cargo volumes and capacities of the ports in the Northern Region are comparatively smaller than the Yangtze River Delta, and the Pearl River Delta. To resolve this issue, one effective strategy is to create additional connections with ports and container ports of nearby countries. Consequently, a Social Network Analysis (SNA), including degree centrality, betweenness centrality, and hub and authority centrality, was used to analyze the route networks of the top three ports (ports of Tianjin, Qingdao, and Dalian) of BREC. A list of ports that are highly influential to these three ports in building additional connections to obtain higher cargo volumes is provided. Keywords: The Bohai Rim Economic Circle, Ports of Northern China, Connection, Social Network Analysis, Port Centrality

Coronary artery fistulas (CAFs) are abnormal communications of coronary arteries whereby venous circuits bypass the normal capillaries within the myocardium. CAFs are rare, and most affected patients are asymptomatic. However, these fistulas are the most common coronary artery anomalies that can alter coronary hemodynamic parameters. Although most CAFs are asymptomatic in young patients, symptoms and complications become more frequent with increasing age. CAFs are characterized by variable clinical manifestations that are based on the size, origin, and drainage site of the fistula. In symptomatic cases, surgical ligation or percutaneous transcatheter closure is often recommended. Although CAFs historically have been evaluated with conventional invasive angiography, electrocardiographically gated cardiac computed tomographic (CT) angiography has emerged as the noninvasive alternative modality of choice owing to the high spatial and temporal resolution and short acquisition time. Furthermore, three-dimensional volume-rendered CT angiograms facilitate accurate assessment of the complex anatomy of CAFs, including their origin, drainage site, and complexity and the number and size of fistulous tracts. Knowledge of these characteristics is crucial for therapeutic planning. Radiologists must be aware of the pathophysiology, clinical manifestations, and characteristic CT angiographic findings of CAFs; appropriate CT angiographic protocols for evaluation of various CAFs; and the role of CT angiography in preprocedural planning and follow-up. Online supplemental material is available for this article. ©RSNA, 2018.

Multi-component (TiZrHf)1Ni1.50Co0.60Cu0.90, (TiZrHf)1Ni1.48Co0.58Cu0.88, (TiZrHf)1Ni1.45Co0.57Cu0.86, and (TiZrHf)1Ni1.40Co0.54Cu0.82 high-temperature shape memory alloys (HTSMAs) were prepared by arc-melting and then microstructures, transformation temperatures, phase constituents and superelasticity were investigated by scanning electron microscope observation, differential scanning calorimetery, X-ray diffraction and dynamic mechanical analysis in tensile mode, respectively. The microstructure of solution treated TiZrHfNiCoCu HTSMAs specimens consisted of (TiZrHf)(NiCoCu)-type matrix and (TiZrHf)2(NiCoCu)-type second phase. The area fraction of the second phase increased from 1.7% to 17.2% with the increased in (TiZrHf) content from 50 at% to 52 at%. Martensitic transformation start temperature of the solution treated specimens increased from 53.5 °C to 188.7 °C with the increase in (TiZrHf) content from 50 at% to 52 at%. TiZrHfNiCoCu HTSMAs showed clear superelasticity in the solution treated state. The superelastic recovery strain of solution treated TiZrHfNiCoCu HTSMAs was in the range of 4.2–4.6% depending on the alloy composition.

Pb powder was investigated as an active material as anode for sodium-ion batteries. Precisely, a Pb anode comprising micrometer-sized Pb powder modified with multi-walled carbon nanotubes was fabricated. The anode showed an excellent rate capability, as well as reversible capacities of 370 mAh g−1 at 12.8 C (6208 mA g−1). In addition, the Pb anode exhibited a stable cycle life during 1000 cycles at 10 C with a high reversible capacity of 423 mAh g−1. Using electrochemical tests, scanning electron microscopy, and energy-dispersive X-ray spectroscopy, we revealed the origin of this excellent performance: the micrometer-sized Pb powder undergoes self-healing during cycling, resulting in fiber-like nanometer-sized Pb particles that reinforce the anode structure and provide fast electron transport pathways.