Nd3+, Y3+: SrF2 transparent ceramics were successfully synthesized by two methods: hot-forming and hot-pressing techniques. The mechanical properties and optical properties of the hot-formed Nd3+, Y3+: SrF2 transparent ceramics were much better than that of single crystal. On the other hand, the transmittance of the hot-formed transparent ceramics with different deformation rate reached up to 90% at 1054 nm, which is superior to the hot-pressed ceramics. Furthermore, the fracture toughness of hot-formed Nd3+, Y3+: SrF2 transparent ceramics with the deformation rate of 51% reached up to 0.70 MPa m1/2, which is nearly 1.5 times higher than that of as-grown single crystal. The full width at half maximum (FWHM) of the hot-formed ceramic is larger than that of the single crystal at 1053 nm under continuous-wave (CW) laser operation. The thermal conductivity of Nd3+, Y3+: SrF2 single crystal and hot-formed ceramics were also discussed.

Semitransparent and homogeneous bismuth oxychloride (BiOCl) thin films with (001) preferred orientation were synthesized on polycrystalline Sn:In 2 O 3 -glass substrates by mist chemical vapor deposition. The films showed photocathodic activity even under near-ultraviolet light within the band gap due to the in-gap states induced by oxygen vacancies. Higher synthesis temperatures resulted in a significant increase of photocurrent density under ultraviolet light. While the longer lifetime of photocarriers led to an increase of internal quantum efficiency, the larger band-edge absorption significantly contributed to the higher external quantum efficiency.

Compressive creep behavior of a Mg-Al alloy containing a small amount of Nd and Gd (Mg-6Al-1Nd-1.5Gd) was investigated at temperatures from 150 °C to 200 °C under a constant applied stress of 90 MPa, and its microstructure before and after creep testing was compared. Results showed that steady-state creep rate of the alloy was only 1.946 × 10−8 /s at 150 °C, and was increased by four times and almost one order of magnitude at 175 °C and 200 °C, respectively. The microstructure of the alloy mainly consists of α-Mg, β-Mg17Al12 phases, and Al2RE phases, which were distributed both in dendrites of α-Mg and at grain boundaries originally. After creep for 120 h, more Al2RE phases were aggregated at grain boundaries. The continuous β-Mg17Al12 phase turned into dispersed dot-like or blocky particles. As the test temperature increased, the number of dislocation lines gradually increased due to the increase of creep strain. Meanwhile, dislocation tangle and dislocation pile-ups occurred near grain boundaries. However, obvious slip traces and slip lines appeared inside α-Mg dendrites at 175 °C and 200 °C, respectively, indicating that 〈c + a〉 non-basal slip system was activated, creep resistance decreased dramatically.

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BackgroundEsophageal squamous cell carcinoma is the predominant subtype of esophageal cancer in China and so differs from presentations in Western countries. Common metastatic locations of esophageal cancer include the liver, lung, bone, and brain. In contrast, metastases in subcutaneous soft tissue are exceedingly rare.Case presentationWe present the experience of a 57-year-old man with a complaint of hand and leg dysfunction on the right side. He had a past medical history of esophageal squamous cell carcinoma. Further imaging workup revealed a solitary brain metastasis, thickening of the esophageal wall, swollen lymph nodes in the mediastinum, and right adrenal gland metastasis. Gamma knife radiosurgery of the brain metastasis and intensity-modulated radiotherapy of the esophagus and lymph nodes were administered. After 1.5 months, he was admitted to our hospital again, and nodules were identified in the anterior abdominal wall and left posterior chest wall. Ultrasound, CT, and radical excision of the abdominal wall mass were undertaken and revealed metastatic squamous cell carcinoma with neuroendocrine differentiation. We administered immunotherapy followed by targeted therapy. A PET/CT scan was performed to identify other organ metastases; the scan revealed multiple areas of fluorodeoxyglucose uptake and foci in the esophagus, lung, liver, bone, and right adrenal gland; and in various lymph nodes. In addition, an intensely hypermetabolic lesion was localized in the left posterior thorax.ConclusionThis case highlights the diagnosis and treatment of uncommon metastases of esophageal squamous cell carcinoma. We hope that our clinical experience provides insights into these uncommon metastases.

TiB2/Mg-4Al-1.5Si magnesium matrix composites were prepared by semi-solid stirring assisted ultrasonic treatment, the primary Mg2Si phases in the composites exhibit polygon with sharp corners, and the eutectic Mg2Si phases appear thin Chinese-script or short-strip shape. To reduce stress concentration around the sharp corners (tips) of the Mg2Si phases, the morphology of the Mg2Si phases was further modified by solution treatment at 420 °C for 24 h, and the effects of the morphology modification of the Mg2Si phases on the mechanical properties of the composites were investigated. The results showed that after the solution treatment, the sharp corners of the primary Mg2Si phases were blunted, and the partial branches of the eutectic Mg2Si phases were dissolved into particles. The Vickers-hardness, ultimate tensile strength, yield strength, and elongation of the composites were increased by 11.50%, 33.28%, 28.57%, and 27.17% compared with those of unmodified composites, respectively. The solution treatment exhibits a more significant strengthening effect for the composites in hardness, ultimate tensile strength, and yield strength compared with the matrix alloys.

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To reduce the density and cost while improving the ductility of creep-resistant Mg-Gd system alloys, a total of 2 wt.% Al and Ca were added to an Mg-10Gd alloy for partial substituting Gd element. The prepared alloys were subjected to solution treatment at 500 OC for several hours, and the variations in microstructure and mechanical properties were investigated. To reveal the effect of the combined addition of Al and Ca on the microstructure and mechanical properties of the Mg-10Gd alloys, Mg-10Gd alloys containing the same amount of Al or Ca were also fabricated and characterized. By comparison, it was found that only the co-addition of Al and Ca simultaneously improved the hardness, ultimate tensile strength, yield strength, and elongation of the Mg-10Gd system alloys in both as-cast and solid solution states.