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Woven fabrics were bestowed with antibacterial property by the simple adsorption of rare-earth metal ions, and the underlying mechanism was investigated using electron spin resonance (ESR) spectroscopy. The adsorption of CeThe online version contains supplementary material available at 10.1007/s11696-021-01999-9.

Background We hypothesized that thermal damage accumulation during endoscopic submucosal dissection (ESD) causes the pathogenesis of post-ESD electrocoagulation syndrome (PECS). Aim To determine the association between Joule heat and the onset of PECS. Methods We performed a retrospective cohort study in patients who underwent colorectal ESD from May 2013 to March 2021 in Japan. We developed a novel device that measures swift coagulation time with a sensor adjacent to the electrosurgical coagulation unit foot switch, which enabled us to calculate total Joule heat. PECS was defined as localized abdominal pain (visual analogue scale ≥ 30 mm during hospitalization or increased by ≥ 20 mm from the baseline) and fever (temperature ≥ 37.5 degrees or white blood cell count ≥ 10000 µ/L). Patients exposed to more or less than the median Joule heat value were assigned to the high and low Joule heat groups, respectively. Statistical analyses included Mann-Whitney U and chi-square tests and logistic regression and receiver operating characteristic curve (ROC) analyses. Results We evaluated 151 patients. The PECS incidence was 10.6% (16/151 cases), and all patients were followed conservatively and discharged without severe complications. In multivariate analysis, high Joule heat was an independent PECS risk factor. The area under the ROC curve showing the correlation between PECS and total Joule heat was high [0.788 (95% confidence interval: 0.666-0.909)]. Conclusion Joule heat accumulation in the gastrointestinal wall is involved in the onset of PECS. ESD-related thermal damage to the peeled mucosal surface is probably a major component of the mechanism underlying PECS.

Este trabajo explora el papel de la música y las emociones en la construcción de los vínculos transnacionales, a partir de dos viñetas etnográficas relacionadas con la nostalgia. Por un lado, esta emoción prevalece en la vida cotidiana de los migrantes mexicanos en Houston, a través de sus diversas prácticas, detrás de las cuales la música popular de México está presente junto con las imágenes del terruño. Por otro lado, en el contexto de la visita de los migrantes y sus familias a los lugares de origen en el noreste de México, la música popular se escucha para expresar su nostalgia e inducir una actitud nostálgica en los espacios de reencuentro familiar y social, creando un paisaje sonoro distinto de la temporada de la ausencia de los migrantes.

Resins were produced from artificial spider protein powder (53–100 µm particles) by hot-pressing at 100–180 °C and 30 MPa with 0–30 wt% added water. These were subjected to three-point bending, optical performance analysis, Fourier-transform infrared (FTIR)-attenuated total reflectance (ATR) spectroscopy, and crystallinity analysis by wide-angle X-ray scattering (WAXS). The resin produced with 30 wt% water and at lower temperature (120 °C) achieved the highest optical translucency, and its bending strength (∼144.6 MPa) and bending modulus (∼8.3 GPa) were comparable to those of high-performance plastics such as polyphenylene sulfide. Compared to silk from domestic silkworms, the high water uptake of this spider protein is attributed to its larger amount of hydrophilic amino acids. Spider protein resin showed slightly higher crystallinity after adding 30 wt% water during hot-pressing (∼39 % vs. ∼37 % without added water). Spectroscopic analyses also suggested that the addition of water promoted the formation of β-sheet (crystal region), supporting the crystallinity results.

Wool is widely used in the apparel industry, and recycling wool will be of great value to this and other sectors in the future. The applications of keratin-derived fibers from wool and chicken feathers as fiber reinforcement for polymers and polymer film have been actively researched. Herein, we tried to prepare a wool resin from woven wool fabric with/without descaling treatment and pulverization(powdering) by hot-pressing at 150–180 °C under 60 MPa. The resin prepared from hot-pressed small powder (Diameter is

Background Metastases of meningiomas are infrequent and the site of extracranial metastasis such as the bone is extremely rare. Case report A 75-year-old male had a history of five sessions of surgery and gamma-knife treatment for brain meningioma over a period of 29 years. He visited our hospital because he noticed a swelling in his anterior chest 2 years and 6 months after the final treatment. After an open biopsy, histopathological analysis revealed the mass to be a metastatic grade II meningioma. We resected the tumor along with the sternum, ribs, pleura, and pericardium. The patient had recurrences in the thoracic cavity and pericardium postoperatively and received radiation therapy. He also had metastasis in the abdominal cavity, which spread rapidly. Conclusion We report on a rare instance of metastasis to the sternum in a case of atypical meningioma, showing rapid growth and invasion after long-term treatment.

This study aims to utilize the thermosetting behavior of native lignin and the self-assembly of silk in coconut coir (CC) and regenerated silk (RS) microparticles used as blends and natural binders for construction and demolition waste (CDW) wood and their effect on the mechanical, thermal, and structural properties of CDW wood/CC, RS/CC, and CDW wood/RS biomicrocomposites. The obtained biomicrocomposites were prepared by hot-pressing blended microparticles at weight ratios of 80:20, 60:40, 50:50, 40:60, and 20:80 in the temperature range of 170–180°C. The obtained biomicrocomposites were characterized by bending strength, water resistance, scanning electron microscopy (SEM), thermogravimetric analysis/derivative thermogravimetry (TGA/DTG), and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) measurements. Findings showed that the incorporation of RS displayed superior enhancement in the mechanical properties and water resistance in CDW/RS. The incorporation of CC slightly improved these properties in CDW/CC and RS/CC but offered greater thermal stability, as shown by thermogravimetric analysis (TGA/DTG). The addition of RS and CC showed good interfacial adhesion, as revealed by SEM. FTIR data revealed strong reactivity among CC, RS, and CDW wood.

Unusual helical single crystals of γ-Dy2S3 were grown from solution by SnS evaporation, and their growth mechanism was investigated. The helical growth of γ-Dy2S3 single crystals is driven by axial screw dislocations, and the crystals grow via the vapor–solid–solid mechanism in the presence of a three-phase interface. Dy2S3 transfers into the vapor phase through a nonequilibrium process owing to simultaneous evaporation of Dy2S3 and SnS. The capture of a nonvolatile component during evaporation is common for solutions comprising volatile and nonvolatile components.

Background: The coronavirus disease 2019 (COVID-19) pandemic has resulted in a total upending of our daily lives. While anxiety and depression were frequently reported among the general population, the pandemic’s impact on patients with mental health problems remains unknown. Methods: A cross-sectional questionnaire survey involving 1,166 patients was conducted at one psychiatric hospital and one mental health clinic. Results: Symptom deterioration was reported in 23% to 34% of the patients and 9% to 20% reported increase in drug dosage. No significant differences were reported in these items among diagnostic categories. Patients with F3 (mood disorders) reported more psychological stress during the pandemic’s beginning and during the emergency. Patients with F2 (schizophrenia, schizotypal, and delusional disorders) did online shopping and meetings less frequently, and reported poorer adherence of 3C’s, while mask management was stricter in patients with F4 (neurotic, stress-related, and somatoform disorders). Symptom deterioration was significantly associated with increase in drug dosage, new physical symptoms, anxiety unrelated to COVID-19, stress at the beginning of pandemic, stress during the ‘state of emergency’, poor adaptability to environmental change, daily life changes, decrease in sleeping time, and decrease in time spent outside. Conclusion: One third of patients reported symptom deterioration during the pandemic, which was associated with stress and daily life changes. Patients with good adaptability to environmental changes might resilient against symptom deterioration. Providing continuous support to help patients manage their daily life in this COVID-19 era may minimize the risk of symptom deterioration.

Stibnite mineral (mainly Sb2S3) has been employed for the synthesis of tetrahedrite Cu12Sb4S13 bulk material by spark plasma sintering. High purity Cu12Sb4S13 can be quickly obtained by two sintering procedures at temperatures from the range of 420 °C to 440 °C for 1 h. Appropriate reduction of Cu content (Cu12+xSb4S13, x ⩽ –0.05) or CuS content (Cu12−ySb4S13−y, y = 0.1 or 0.3) was beneficial to fabricate Cu12Sb4S13. The secondary resintering improved the purity of Cu12Sb4S13 material. The first-order magnetic phase transformation with magnetic hysteresis effect was confirmed by the behavior of susceptibility, heat capacity and resistivity. The magnetization showed a linear increase with increasing field (up to 7 T) and non-saturation behavior was observed. The impurities in stibnite mineral Sb2S3 had a weak influence on the transformation temperature but affected the low-temperature magnetization value (~0.15, close to natural tetrahedrite). Similar transformation was observed by the analysis of heat capacity. The properties such as electrical resistivity, Seebeck coefficient and thermal conductivity were also measured for Cu11:9Sb4S13 and Cu11:9Sb4S12:9. The maximum figure of merit ZT of Cu11:9Sb4S12:9 was 0.22 at 367 K.

Ag/AgCuS/CuInS2 hybrid nanoparticles (HNPs) were synthesized via a reductive cation exchange method. In this reaction, selective formation of Ag+ vacancies was achieved via direct reduction of Ag+ ions in AgCuS using a mixture of 1-dodecanethiol and tri-n-octylamine. AgCuS underwent a phase transition from orthorhombic (β-) to superionic δ-AgCuS phase with a face-centered cubic sulfur sublattice. This phase transition increased cation mobility during the cation exchange process. Below the phase transition temperature, the lower ionic conductivity of the orthorhombic phase prevents cation and hole diffusions through the interface between AgCuS and CuInS2 to stabilize a AgCuS/CuInS2 heterostructure. Transmission electron microscopy analyses revealed that the β-AgCuS/CuInS2 interface was composed of (010) or (001) β-AgCuS and (112) CuInS2. Because of the band alignment of Ag/AgCuS/CuInS2, the Ag NP tended to deposit on the surface of the AgCuS domain of the HNP. This selective redox reaction on the AgCuS domain may induce an electromotive force that plays an important role in the formation of the asymmetric heterostructure. Our proposed method may provide a novel strategy for the synthesis and precise structural tuning of metal/semiconductor hetero-nanostructures.

A superconducting joint between two Gd123-coated conductors was successfully formed using crystal growth in the bulk (CJMB). An intermediate Yb123 layer was used at the junction, and was melted to form a joint by heat treatment at a temperature below the melting point of the RE123 (such as Gd123) in the coated conductor. This liquid-phase bonding results in high tensile strength, which has exceeded 100 MPa in previous studies. Nevertheless, the joint principle has not been sufficiently clarified. In this study, we performed microstructural analysis of the joint using X-ray diffraction and scanning electron microscopy combined with energy-dispersive X-ray spectroscopy to form a clearer understanding of the joint formation mechanism in order to achieve a high critical current in the junction.

For application to ultrahigh-field nuclear magnetic resonance spectroscopy (e.g., 30 T), we have started to develop a REBa2Cu3O $_{7-\delta}$ (RE123, RE: rare earth) multi-core coated conductor in which the ceramic layers (RE123 and buffer layers) are electrically separated to create multiple filaments. This method is called electrical separation by inner splitting, and the wire is called a split wire. The multi-core structure is fabricated using electrical separation by a phase stress, which utilizes the difference in toughness between ceramics and metal, such as partial V-bending by stress along the longitudinal direction of the coated conductor using a commercially available single-core RE123 coated conductor. In addition, about ten narrow cores (width: 5–15 μm) can be formed by one bending. These cores are called subcores. The wire is composed of main cores and subcores. In this study, a 4-mm-wide multifilamentary RE123 split wire with 16 main cores and 150 subcores was fabricated and evaluated. The manufacturing method, microstructure, and critical current properties under an external magnetic field and tension are presented.

Mexican immigrants who move to the United States exert great influence on the reproduction of tradition in regional Mexican cities. This study examined the “changes in vistas” that appear due to the frequent migration that connects global cities with sending societies. The emphasis here is on the realities in which residents upgrade their living spaces using traditionality with their own unique strategies (posttraditional vistas), despite social and financial restrictions. Employing ethnographic methods and measurement surveys of housing, this study focused on Jalostotitlán, Jalisco, Mexico. It was found that changes in the vista of Jalostotitlán have not resulted from the unidirectional impact of people, goods, and money flowing from global cities; rather, they have arisen from the bidirectional relationship between immigrants and their hometowns. This research helps to depict another factor for discussions of the global migration narrative by placing regional cities at the core.

We investigate the mechanical properties and structure of silk resins as potential alternatives to tortoiseshell for producing eyeglass frames and various ornaments. Silk powders are obtained from Bombyx mori and Eri silk waste fibers before the degumming process. The powders are fabricated into resins via simple hot pressing under a pressure of 31.2 MPa at temperatures in the range 150–180 °C. The results indicate that the B. mori resins have higher micro-Vickers hardness, three-point bending strength, and elastic modulus (66 Hv, 122 MPa, and 8.7 GPa, respectively) compared to the Eri silk resins (58 Hv, 95 MPa, and 8.2 GPa, respectively). The better mechanical properties of the fibroin resins are related directly to longer drying times. The optimum drying conditions are found to be at a temperature of 100 °C under a–vacuum of −0.1 MPa for a time of 7 d. ATR-FTIR and XRD results show how the fibroin structure changes after resinification and drying. The morphology and the distribution size of particle of the silk powders and the fractured surfaces of the resins are analyzed from SEM micrographs. The present findings demonstrate that silk resins are suitable materials for developing useful applications because of their favorable mechanical properties.

The preparation, sintering and low-temperature physical properties of four kinds of ytterbium sulfides (η-Yb2S3, e-Yb2S3, Yb3S4 and YbS) were systematically investigated. The suitable sintering processes were ensured for each ytterbium sulfide. SEM results suggested the sintered ytterbium sulfides had high dense. The measured susceptibility and magnetization of ytterbium sulfides suggested Yb was mainly trivalent in η-Yb2S3 and e-Yb2S3. Moreover, the magnetroresistivity of η-Yb2S3 and YbS shows semiconductor behavior. The resistivity of orthorhombic η-Yb2S3 is consistent with Kondo-like characteristic (logarithmic increase with decreasing temperature), while the ρ(T) behavior of YbS is contrast to the Kondo-like behavior. The contribution of electron, lattice and magnetism to heat capacity of ytterbium sulfides was analyzed. For η-Yb2S3, Yb3S4 and YbS, the crystal electron field (CEF) ground state is a Kramers doublet while for e-Yb2S3 it changed to quartet (Γ8). Chemical composition and crystal structure had strong influence on the heat capacity of lanthanide sesquisulfides.

This research reports the processability and mechanical properties of silk resins prepared by hot-pressing followed by hot-rolling and then analyzes their thermal and structural properties. The results show that regenerated silk (RS) resins are better suited for hot-rolling than Eri and Bombyx mori silk resins (untreated silk). When hot-rolling at 160 &deg, C with a 50% of reduction ratio, maximum bending strength and Young&rsquo, s modulus of RS resin reaches 192 MPa and 10.2 GPa, respectively, after pretreatment by immersion in 40 vol% ethanol, and 229 MPa and 12.5 GPa, respectively, after pretreatment by immersion in boiling water. Increased strength of the material is attributed to the increased content of aggregated strands and intramolecular linking of &beta, sheets (attenuated total reflectance Fourier-transform infrared spectroscopy) and higher crystallinity (X-ray diffraction analysis). After hot-pressing and hot-rolling, RS resins have a stable decomposition temperature (297 &deg, C).

Single-phase Eu3S4 was obtained via CS2 gas sulfurization of Eu2O3 nanospheres at 773 K for longer than 0.5 h. The primary particle size of Eu3S4 became larger than that of Eu2O3 during the sulfurization process. Pure synthetic Eu3S4 powders were unstable and transformed to EuS at 873 K under vacuum. Eu3S4 compacts were sintered in temperature range of 773 K to 1173 K and they transformed to EuS at 1473 K during spark plasma sintering. Specific heat of sintered Eu3S4 did not show an anomalous behavior in the range of 2 K to 50 K. The magnetic susceptibility of polycrystalline Eu3S4 followed a Curie-Weiss law from 2 K to 300 K. Magnetization of polycrystalline Eu3S4 was larger than that of single crystal Eu3S4 when the magnetic field was less than 3.5 kOe.

Silk fibroin powder and biodegradable polybutylene adipate terephthalate (PBAT)/poly lactide (PLA) blends were melt-mixed together to fabricate natural and synthetic polymers as possible new sources of biomaterials. Morphological observations conducted through scanning electron microscopy indicated poor dispersion of the silk powder agglomerates, which resulted from strong hydrogen interactions between silk powder chains in the PBAT/PLA matrix. Although the silk powder agglomerates decreased the mechanical properties, as silk powder fractions increased, the ternary blend with 10 wt % silk powder still displayed high impact strength of 108 J/m and tensile modulus of 1.2 GPa. On the basis of mechanical analysis, this blend offered potential applications in fields which required high impact strength. Blends which contained Joncryl experienced a decrease in storage modulus. Furthermore, rheological studies confirmed that the viscosity of the PBAT/PLA/Silk powder blends decreased, which indicated possible weakening of hydrogen bonds between the silk chains, caused by the reaction between the epoxy groups of Joncryl. This reaction provides a possible method to improve the processability of this natural polymer and to improve its distribution in polymer blends.

Detailed pressure-temperature phase diagrams of heavy lanthanide sesquisulfides Ln2S3 (Ln = Yb and Lu) have been investigated by in-situ x-ray diffraction experiments under high pressure and high temperature using synchrotron radiation and multi-anvil press. Based on the results of the in-situ observation, the single γ-phase (Th3P4-type structure, I 4 ¯ 3d) samples of Ln2S3 (Ln = Yb and Lu) have been synthesized under high pressure. The physical properties of the compounds were studied by electrical resistivity, specific heat, and magnetic susceptibility measurements between 2 K and 300 K.

Protein fibers, including wool fibers, selectively adsorb precious-metal ions; hence, they can potentially be used in wastewater treatment applications. Herein, we examined metal-ion adsorption by woven wool fabric and wool resins, especially the adsorption of Pd(II). When woven wool fabrics are treated with chlorine, the cuticle layer is removed from the fiber surface; this treated fabric showed superior Pd(II)-adsorption performance compared with untreated fabric, with a Pd recovery of 81% from an aqueous solution containing 500 mg L−1 Pd(II) for 24 h at 25 °C, which is superior to that of lignin-based adsorbents. The chlorine-treated woven wool fabric and wool resin prepared from this fabric preferentially adsorb Pd when placed in simulated industrial wastewater, even if it contains a variety of other metal ions (e.g., Pd(II), Ni(II), and Cu(II)). Therefore, wool fabrics and resins produced from wool waste can be used as selective adsorbents for the recovery of precious metals such as Pd.

A preliminary study was performed on the resinification behavior of regenerated feather keratin powder by changing the sintering conditions, and the thermal and mechanical properties for the obtain...

The rare-earth semiconductor β-Ce2S3 compound samples were synthesized and their dielectric permittivity and electrical conductivity were measured in the temperature range 90–400 K. The energy-band structure has been determined. It is shown that the long-known large electrical parameter spread of semiconductor compounds close in composition to Ce2S3 is explained by the structure of impurity donor levels formed by cerium atoms and ions with different ionization degrees.

A case of a 64-year-old woman who had undergone resection of a femoral giant cell tumor in another hospital 35 years before was referred to our hospital for diabetes education. Chest radiography and computed tomography (CT) revealed diffuse densely calcified nodular lesions that appear to be in both lung fields. Since pulmonary metastases of the giant cell tumor of the bone was suspected, she underwent a lung biopsy, which showed diffuse pulmonary ossification (DPO) of the dendriform type. It is extremely rare that idiopathic DPO is diagnosed by lung biopsy.

Dans cet essai, nous souhaitons proposer une approche des espaces urbains par les sciences sociales qui mobilise l’étude des nostalgies en tant qu’émotions, pratiques et discours. Parce que la nostalgie est une caractéristique de notre ère, nous proposons de la penser comme catégorie d’analyse pour approcher les expériences vécues des individus qui vivent les changements toujours plus rapides de notre monde hypermobile, hyperconnecté, où le processus de destruction créative semble s’imposer comme modèle urbain hégémonique. Dans ce cadre, nous voulons démontrer que cette catégorie permet de dépasser la séparation pré-établie entre individus mobiles (les migrants) et immobiles (les natifs) pour penser l’être humain face aux changements parfois brutaux qu’impose le monde urbain actuel. A partir de la comparaison de leurs expériences de recherche respectives, les auteurs, géographes, anthropologue et sociologue, cherchent à partager leur réflexion collective sur la nostalgie, en présentant ses apports dans le champ des sciences sociales en général et dans les études urbaines en particulier. In this essay, we wish to propose an approach of urban spaces by the social sciences which mobilizes the study of nostalgia as sentiment, practice and discourse. Because nostalgia is a characteristic of our era, we propose to think of nostalgia as a category capable of analyzing the lived experiences of the individuals who live in the movements of our hypermobile, hyperconnected world, where the process of creative destruction seems to impose itself as a hegemonic urban model. In this context, we want to show that this category makes it possible to overcome the pre-established separation between mobile (migrants) and immobile individuals (the natives) to think of the human being in the face of the brutal changes imposed by the urban world. From the comparison of their respective research experiences, the authors, geographers, anthropologists and sociologists, seek to share their collective reflection on nostalgia, by presenting their contributions in the field of social sciences in general and in urban studies in particular.

Pigmented paraganglioma of the anterior mediastinum is extremely rare. We report a 72-year-old female patient who was pointed out an anterior mediastinum tumor showed by chest computed tomography(CT) scan during a medical check up. The tumor was 50×35 mm showing gradual enlargement and was slightly homogenously contrasted by CT scan and magnetic resonance imaging(MRI). During the resection of the tumor, sudden elevations of both blood pressure up to 205 mmHg and tachycardia up to 131 beat per minate(bpm)was noted on tumor manipulation. Pathologically, the tumor was diagnosed as pigmented paraganglioma with adjacent lymph node metastasis and microscopic extracapsular invasion. The patient is well 5 years post-surgery without recurrence.

A systematic study on the existence of R2Pd3Ge5 intermetallics with heavy rare earth metals (R = Gd–Lu) was conducted; only the Yb2Pd3Ge5 was revealed to exist. Its crystal structure was established by X-ray powder diffraction and refined by means of Rietveld method. This compound crystallizes in the orthorhombic U2Co3Si5 structure type (Ibam, oI40, Z = 4, a = 10.2628(1), b = 12.0580(1), and c = 5.98251(6) A), which represents an ordered derivative of the tI10-ThCr2Si2 prototype, ubiquitous among intermetallics. Magnetization and susceptibility measurements indicate that Yb2Pd3Ge5 is a paramagnet with μeff close to 0.8 μB/Yb-atom, suggesting a nearly divalent Yb state. Electrical resistivity and Seebeck coefficient of the studied compound as a function of temperature confirm its metallic-like behavior.

With its specific physical property of antiferromagnetism, holmium monosulfide (HoS) is considered as an attractive material for potential application in electronic and magnetic recording devices. The HoSx synthesis through the direct interaction of the Ho metal with S does not always attain a homogeneous state because of the large difference between the vapor pressures of Ho and S. We report herein the HoSx synthesis (0.68 ≤ x ≤ 1.2) by the direct reaction of Ho2S3 and Ho using a pulse electric current sintering apparatus. The sintering compacts of the HoS single phase are obtained when the preparation ratios of the Ho metal range from 16.16 (HoS1.19) to 38.15 (HoS0.99) mass% at a sintering temperature of 1973 K. The effect of the Ho addition on the lattice constant, melting point, and electrical resistivity is studied within the homogeneity range of the HoS phase. Consequently, we found that the lattice constant and the melting temperature gradually increase when the composition is close to the stoichiometric composition and reach the values of 5.458 A and 2608 K of HoS1.01, respectively. All the homogeneous HoSx compacts, except HoS0.99, show metallic behaviors down to 50 K, whereas a semiconducting-like upturn can be observed below 20 K. On the other hand, HoS0.99 shows a metallic behavior to 4 K, which indicates that the lattice imperfection considerably affects the electric properties of HoSx. The advantages of the sintering process for the HoSx compact preparation with higher density and a peculiar interface are demonstrated.

In this study, the effects of Eu2O3 characters and sulfurization conditions on the preparation of EuS were researched. Single-phase Eu3S4 and EuS powders can be obtained via CS2 gas sulfurization of spherical Eu2O3 powders with larger specific surface area and small grain size at 500 °C for longer than 0.5 h and 800 °C for 8 h, respectively. Moreover, EuS powders can be fabricated from self-prepared needle Eu2O3 powders at 750 °C for 8 h. However, single phase EuS was generated from oval Eu2O3 powder with large grain size at 900 °C for 2 h. The higher sulfurization temperature and shorter sulfurization time accelerated the formation of high purity EuS. The synthetics have some reunion and the shapes of synthesized EuS are similar. Specific surface area of synthetics lessened with the rising of sulfurization temperature and time. Magnetization curves of polycrystalline EuS bulk are similar with those of single crystal EuS and the maximum values of entropy change are 16.76 J/Kg/K and 28.4 J/Kg/K for the field changes of 2 T and 5 T, respectively.

We present magnetocaloric effect measurements of the ferromagnetic semiconductor EuS in the vicinity of its ordering temperature. Single phase EuS powder was synthesized by CS2 gas sulfurization of Eu2O3. A sintered compact with relative density over 95% was prepared by pulsed electric current sintering of the powder. Temperature and magnetic field dependence of the magnetization and specific heat were characteristic of a paramagnetic to ferromagnetic second order phase transition. The entropy change induced by an external magnetic field and the specific heat were both close to those of a single crystal. We obtained an entropy-temperature (S–T) diagram of the EuS sintered compact. Carnot cycle liquefaction of hydrogen using EuS was compared with several other materials, with results indicating that sintered EuS is an excellent magnetic refrigerant for hydrogen liquefaction. © 2016 Elsevier Ltd, Embargo Period 36 months

Non-stoichiometric samarium monosulfide (SmSx, 0.55≤x≤1.2) was synthesized from Sm2S3 and SmH3 at 1273 K for 3 h under vacuum. The influence of reaction ratio of Sm2S3 to SmH3 on the fabrication of SmSx was investigated. The fabrication of SmS required the molar ratio of Sm2S3 to SmH3 above 1. Lattice parameter of synthetic SmSx increased firstly and then decreased to saturate following with the addition of SmH3 content. SmSx compact was sintered at 1373 K by spark plasma sintering. Density of synthetic SmSx was about 99% of theory density. Seebeck coefficient of n-type semiconductor SmSx decreased as temperature rose. The absolute value was distributed between 170–280 μV/K. The electrical resistivity of SmSx (0.86≤x≤1.07) decreased with temperature increasing and showed similar temperature dependence. The surplus Sm which randomly distributed in the SmSx (0.55≤x≤0.75) matrix led to a remarked reduction of electrical resistivity. The optimized power factor for SmS0.6 and SmS0.75 could reach 1500 μW/(K2·m) at 600 K.

The formation of europium sulfides (Eu3S4 and EuS) via CS2 gas sulfurization of Eu2O3 powder was investigated. Single-phase Eu3S4 was obtained via CS2 gas sulfurization of Eu2O3 at 773 K for periods longer than 0.5 hr and EuS was generated by sulfurization at 1073 K for 8 hr. The higher sulfurization temperature and shorter sulfurization time accelerated the formation of high purity EuS. Synthetic pure Eu3S4 was treated under vacuum, rich-sulfur atmosphere and inert atmosphere, respectively. EuS was obtained when heat treatment was performed at 873 K under vacuum, at 973 K under CS2/Ar atmosphere, and at 1073 K under Ar atmosphere. Heat treatment of Eu3S4 generated a small amount of Eu2O2S due to impurity oxygen. Formation of Eu2O2S could be inhibited by heat treatment under CS2/Ar atmosphere.

Este artículo propone el uso del concepto “itinerario subjetivo” para analizar los elementos que componen el proceso migratorio de retorno de los jóvenes mexicanos de la generación 1.5. Con base en la descripción y el análisis de la narrativa de un joven que pertenece a esta generación de migrantes que retornó a México, se discutirán las características de esta movilidad de regreso y el proceso de resocialización, así como la forma en que los jóvenes retornados interpretan sus historias migratorias, narran sus emociones y su sentido de pertenencia, y construyen las expectativas de su futuro. This article proposes the use of the concept “subjective itinerary” as an analytical tool to examine the elements that constitute the return migration process of Mexican youth who belong to the 1.5 generation. Drawing from the description and analysis of the narrative of a young 1.5 man who returned to Mexico, the characteristics of return mobility and socialization process will be discussed, as well as the ways in which young returnees interpret their own migration stories, narrate their emotions and sense of belonging, and build expectations for their future.