Deoxofluorination of graphite oxide with sulfur tetrafluoride

In this study, deoxofluorination of graphite oxide (GO) using sulfur tetrafluoride (SF₄) at a temperature below the decomposition temperature of GO (∼200 °C) was investigated for the first time with and without HF catalysis. At 25 °C, the reaction proceeds only at high SF₄ pressures (≥8 atm) when not catalyzed by HF and at 1 atm SF₄ under the catalysis of HF. The degree of fluorination increases at higher temperatures and SF₄ pressures. Hydroxy and carbonyl groups are replaced by fluorine following this reaction, and SF₄ and SOF₂ are introduced into the product, while the epoxy groups do not react. SF₄ and SOF₂ in the products are removed by washing with water. The obtained product is less hygroscopic than pristine GO owing to the hydrophobicity of the fluorine atom. The interlayer separation of the product is increased after deoxofluorination despite the smaller size of fluorine than the sizes of the oxygen-containing functional groups. When compared with direct fluorination using elemental fluorine, deoxofluorination using SF₄ has the advantages of high reactivity with hydroxy groups and the preservation of the carbon skeleton, and the reaction results in the formation of graphite oxyfluoride

Exploring 3P0^3P_0 Superfluid in Dilute Spin-Polarized Neutron Matter

We explore the theoretical possibility of $^3P_0$ neutron superfluid in dilute spin-polarized neutron matter, which may be relevant to the crust region of a magnetized neutron star. In such a dilute regime where the neutron Fermi energy is less than 1 MeV, the $^1S_0$ neutron superfluid can be suppressed by a strong magnetic field of the compact star. In the low-energy limit relevant for dilute neutron matter, the $^3P_0$ interaction is stronger than the $^3P_2$ one which is believed to induce the triplet superfluid in the core. We present the ground-state phase diagram of dilute neutron matter with respect to the magnetic field and numerically estimate the critical temperature of the $^3P_0$ neutron superfluid, which is found to exceed $10^7$ K.Comment: 6 pages, 3 figure

Fatigue experiment and assessment of butt-welded joints in steel structures considering misalignment and weld geometry effects

Luo P., Mashino Y., Matsuo Y., et al. Fatigue experiment and assessment of butt-welded joints in steel structures considering misalignment and weld geometry effects. International Journal of Fatigue 182, 108200 (2024); https://doi.org/10.1016/j.ijfatigue.2024.108200.This study investigates the fatigue behavior of butt-welded joints considering the effects of misalignments and weld geometries. Fourteen specimens were fabricated with varied assembly root gaps and axial eccentricities, and they were subjected to cyclic tensile loading with constant amplitude. Misalignments (both axial and angular) and weld geometries (including weld toe radius, flank angle, weld reinforcement height, and width) were measured using a 3D optical scanning system and subsequently used for fatigue evaluation in terms of fatigue crack locations and fatigue strength. The fatigue test results indicate a noticeable decrease in nominal stress fatigue strength as the assembled axial eccentricities increase, regardless of the assembled root gaps. However, the correlation between assembled root gaps and fatigue strength is not clear, as a larger assembled root gap corresponds to a flatter weld reinforcement on one hand and an increase in angular misalignment on the other hand. Several stress magnification factor (SMF) and stress concentration factor (SCF) formulae available in the literature are employed to characterize the combined effects of misalignment and weld geometries. The investigation results indicate that misalignments and weld geometries both play critical roles in the fatigue behavior of butt-welded joints. The combination of Remes and Varsta's SCF formula with Luo et al.'s SMF formula is the most recommended method due to its accuracy and robustness regarding the evaluation of both the fatigue crack locations and fatigue life in the investigated butt-welded joints

イ ジョウコウ ケッチョウ チョクチョウ ノ 3 チョウフクガン ニ タイシテ イッキテキ ニ フククウキョウカ シュジュツ オ シコウ シタ 1レイ

A ５１-years-old man was admitted with anemia. The upper gastrointestinal endoscopy revealed ０-IIa＋IIc lesion in the middle body of the stomach. The colonoscopy revealed type ３ lesion by Borrmann classification with advanced stenosis. Computed tomography of the abdomen revealed the tumor in the ascending colon. We diagnosed a synchronous gastric, ascending colon, and rectal cancer. After neoadjuvant chemotherapy, we performed the laparoscopic operation for the synchronous cancer. There were no remarkable complications due to the collaboration. Laparoscopic approach for synchronous triple cancer is feasible as safety and minimally invasive surgery

Mesh-Airtight-Preperitoneum : a simple method for confirming mesh placement in transabdominal preperitoneal repair of inguinal hernia

We devised a method for confirming the position of mesh placed during transabdominal preperitoneal repair (TAPP) of an inguinal hernia. The preperitoneum is sufficiently detached, and the mesh is fixed in place as usual. Before completely closing the peritoneum, pressure is applied from outside the body and inside the abdominal cavity to remove as much air as possible from the detached preperitoneum ; the peritoneum is then sutured using a V-LocTM closure device so that it does not constrict. By releasing the pressure all at once, the airtightness of the preperitoneum is maintained, and the position of the mesh can be observed through the translucent peritoneum. This method, called Mesh-Airtight-Preperitoneum (MAPP), could become widely used as a simple technique for confirming mesh position in TAPP

キョウセン ヒテイケイテキ カルチノイド ノ 1セツジョレイ

Background. Thymic carcinoids are rare disease to account for ２-４％ of anterior mediastinal tumors. So, the clinicopathologic characters are not known enough. Case. A ６７ years old man was followed up old myocardial infarction, and he was taken chest CT scan for evaluate coronary artery. It revealed three anterior mediastinal tumors and we diagnosed thymoma by needle biopsy. We treated by neoadjuvant chemotherapy（CAMP therapy）, but it was ineffective. We performed thoracoscopic thymothymomectomy, and the pathological diagnosis was thymic atypical carcinoid. He is free of clinically event recurrence one year and a half after treatment. Conclusions. When we found an anterior mediastinal tumor, and if the clinical course is usually different, we should consider the possibility of a thymic carcinoid