Synthesis and crystal structure of novel nonstoichiometric suboxide solid solutions, Ti12−δGaxBi3−xO10

Single crystals of new Ti12−δGaxBi3−xO10 compounds (x = 1.42–1.74, δ = 0.77–0.62) were prepared at 900 °C with a Bi flux. Crystal structure analysis by X-ray diffraction (XRD) revealed that the solid solutions are isostructural with Ti12−δSn3O10 (cubic, space group Fm-3m).1) The δ and x values were determined by refinement of the occupancies for the Ti2 and Ti4 sites, and Ga site, respectively (Table 1). The cell parameter a decreases from 13.5616(3) Å to 13.5402(5) Å with increasing Ga content, x, while the total valence electron number of Ti12−δGaxBi3−xO10 was maintained at 117.1 by decreasing Ti defects, δ. Stella octangula is formed by sharing of the edges of four supertetrahedra composed of O-centered Ti tetrahedra and trigonal bipyramids (oxide part) (Figure 1). Another superpolyhedron is formed by sharing of the pyramidal planes of Ga/Bi-centered Ti mono-caped square antiprisms (intermetallic part). These two parts are incorporated in the structure. A polycrystalline bulk of a solid solution with x = 2.01, δ = 0.67 (a = 13.53772(13) Å) was synthesized by reaction sintering at 950 °C from the mixture of Ti, TiO2, Bi2O3, and Ga2O3. The resistivities measured for the bulk were 2.2–2.4×10−5 Ωm in the temperature range from 10 K to 300 K. Please click Additional Files below to see the full abstract

Flexible Mono-tread Mobile Track (FMT) - A New Mobile Mechanism Using One Track and Vertebral Structure -

Non

Consistent map building in petrochemical complexes for firefighter robots using SLAM based on GPS and LIDAR

The objective of this study was to achieve simultaneous localization and mapping (SLAM) of firefighter robots for petrochemical complexes. Consistency of the SLAM map is important because human operators compare the map with aerial images and identify target positions on the map. The global positioning system (GPS) enables increased consistency. Therefore, this paper describes two Rao-Blackwellized particle filters (RBPFs) based on GPS and light detection and ranging (LIDAR) as SLAM solutions. Fast-SLAM 1.0 and Fast-SLAM 2.0 were used in grid maps for RBPFs in this study. We herein propose the use of Fast-SLAM to combine GPS and LIDAR. The difference between the original Fast-SLAM and the proposed method is the use of the log-likelihood function of GPS; the proposed combination method is implemented using a probabilistic mathematics formulation. The proposed methods were evaluated using sensor data measured in a real petrochemical complex in Japan ranging in size from 550–380 m. RTK-GPS data was used for the GPS measurement and had an availability of 56%. Our results showed that Fast-SLAM 2.0 based on GPS and LIDAR in a dense grid map produced the best results. There was significant improvement in alignment to aerial data, and the mean square root error was 0.65 m. To evaluate the mapping consistency, accurate 3D point cloud data measured by Faro Focus 3D (± 3 mm) was used as the ground truth. Building sizes were compared; the minimum mean errors were 0.17 and 0.08 m for the oil refinery and management building area and the area of a sparse building layout with large oil tanks, respectively. Consequently, a consistent map, which was also consistent with an aerial map (from Google Maps), was built by Fast-SLAM 1.0 and 2.0 based on GPS and LIDAR. Our method reproduced map consistency results for ten runs with a variance of ± 0.3 m. Our method reproduced map consistency results with a global accuracy of 0.52 m in a low RTK-Fix-GPS environment, which was a factory with a building layout similar to petrochemical complexes with 20.9% of RTK-Fix-GPS data availability

Consistent map building in petrochemical complexes for frefghter robots using SLAM based on GPS and LIDAR

The objective of this study was to achieve simultaneous localization and mapping (SLAM) of frefghter robots for petrochemical complexes. Consistency of the SLAM map is important because human operators compare the map with aerial images and identify target positions on the map. The global positioning system (GPS) enables increased consistency. Therefore, this paper describes two Rao-Blackwellized particle flters (RBPFs) based on GPS and light detection and ranging (LIDAR) as SLAM solutions. Fast-SLAM 1.0 and Fast-SLAM 2.0 were used in grid maps for RBPFs in this study. We herein propose the use of Fast-SLAM to combine GPS and LIDAR. The diference between the original FastSLAM and the proposed method is the use of the log-likelihood function of GPS; the proposed combination method is implemented using a probabilistic mathematics formulation. The proposed methods were evaluated using sensor data measured in a real petrochemical complex in Japan ranging in size from 550–380 m. RTK-GPS data was used for the GPS measurement and had an availability of 56%. Our results showed that Fast-SLAM 2.0 based on GPS and LIDAR in a dense grid map produced the best results. There was signifcant improvement in alignment to aerial data, and the mean square root error was 0.65 m. To evaluate the mapping consistency, accurate 3D point cloud data measured by Faro Focus 3D (± 3 mm) was used as the ground truth. Building sizes were compared; the minimum mean errors were 0.17 and 0.08 m for the oil refnery and management building area and the area of a sparse building layout with large oil tanks, respectively. Consequently, a consistent map, which was also consistent with an aerial map (from Google Maps), was built by Fast-SLAM 1.0 and 2.0 based on GPS and LIDAR. Our method reproduced map consistency results for ten runs with a variance of ± 0.3 m. Our method reproduced map consistency results with a global accuracy of 0.52 m in a low RTK-Fix-GPS environment, which was a factory with a building layout similar to petrochemical complexes with 20.9% of RTK-Fix-GPS data availability

Controversy and consensus on the management of elevated sperm DNA fragmentation in male infertility: A global survey, current guidelines, and expert recommendations

Purpose Sperm DNA fragmentation (SDF) has been associated with male infertility and poor outcomes of assisted reproductive technology (ART). The purpose of this study was to investigate global practices related to the management of elevated SDF in infertile men, summarize the relevant professional society recommendations, and provide expert recommendations for managing this condition. Materials and Methods An online global survey on clinical practices related to SDF was disseminated to reproductive clinicians, according to the CHERRIES checklist criteria. Management protocols for various conditions associated with SDF were captured and compared to the relevant recommendations in professional society guidelines and the appropriate available evidence. Expert recommendations and consensus on the management of infertile men with elevated SDF were then formulated and adapted using the Delphi method. Results A total of 436 experts from 55 different countries submitted responses. As an initial approach, 79.1% of reproductive experts recommend lifestyle modifications for infertile men with elevated SDF, and 76.9% prescribe empiric antioxidants. Regarding antioxidant duration, 39.3% recommend 4–6 months and 38.1% recommend 3 months. For men with unexplained or idiopathic infertility, and couples experiencing recurrent miscarriages associated with elevated SDF, most respondents refer to ART 6 months after failure of conservative and empiric medical management. Infertile men with clinical varicocele, normal conventional semen parameters, and elevated SDF are offered varicocele repair immediately after diagnosis by 31.4%, and after failure of antioxidants and conservative measures by 40.9%. Sperm selection techniques and testicular sperm extraction are also management options for couples undergoing ART. For most questions, heterogenous practices were demonstrated. Conclusions This paper presents the results of a large global survey on the management of infertile men with elevated SDF and reveals a lack of consensus among clinicians. Furthermore, it demonstrates the scarcity of professional society guidelines in this regard and attempts to highlight the relevant evidence. Expert recommendations are proposed to help guide clinicians

Synthesis and Crystal Structure of Suboxide Solid Solutions, Ti_12−δGa_<i>x</i>Bi_3–<i>x</i>O₁₀

Single crystals of suboxide solid solutions Ti_12−δGa_<i>x</i>Bi_3–<i>x</i>O₁₀ (<i>x</i> = 1.42–1.74; δ = 0.77–0.62) were prepared at 900 °C with a Bi flux. Crystal structure analysis by X-ray diffraction (XRD) revealed that the solid solutions are isostructural with Ti_12−δSn₃O₁₀ (cubic, space group <i>Fm</i>3̅<i>m</i>). The cell parameter <i>a</i> decreases from 13.5616(3) to 13.5402(5) Å with increasing Ga content, <i>x</i>, while the total valence electron number of Ti_12−δGa_<i>x</i>Bi_3–<i>x</i>O₁₀ is maintained at 117.1 by decreasing Ti defects, δ. Stella octangula is formed by sharing of the edges of four supertetrahedra composed of O-centered Ti tetrahedra and trigonal bipyramids (oxide part). Another superpolyhedron is formed by sharing of the pyramidal planes of Ga/Bi-centered, Ti-monocapped square antiprisms (intermetallic part). These two parts are incorporated in the structure. A polycrystalline bulk of a solid solution with <i>x</i> = 2.01 and δ = 0.67 [<i>a</i> = 13.53772(13) Å] was synthesized by reaction sintering at 950 °C from a mixture of Ti, TiO₂, Bi₂O₃, and Ga₂O₃. The resistivities measured for the bulk were (2.2–2.4) × 10^–5 Ω m in the temperature range from 10 to 300 K

Ternary Suboxides Ti₇Ga₂O₆, Ti₃GaO, and Ti₅Ga₃O

Single crystals of the new suboxides Ti₇Ga₂O₆ and Ti₃GaO were prepared using a Bi flux. Ti₇Ga₂O₆ has a novel monoclinic crystal structure (<i>a</i> = 17.3111(8) Å, <i>b</i> = 2.97660(10) Å, <i>c</i> = 7.2563(3) Å, β = 105.836(2)°, space group <i>C</i>2/<i>m</i>), in which three O sites and one Ga site are separately coordinated by Ti atoms. Ti₃GaO crystallizes in an orthorhombic cell (<i>a</i> = 3.0952(2) Å, <i>b</i> = 10.6440(7) Å, <i>c</i> = 8.3206(5) Å, space group <i>Cmcm</i>) with a filled-Re₃B type (anti-CaIrO₃ type or antipost-perovskite type) structure. The electrical resistivities of a single crystal of Ti₃GaO as measured in the <i>c</i>-axis direction were 1.6 × 10^–6 Ωm at 300 K and 0.15 × 10^–6 Ωm at 10 K. Single crystals of Ti₅Ga₃O_<i>x</i> (<i>x</i> = 1) with a filled-Mn₅Si₃ type structure (hexagonal, <i>a</i> = 7.5882(2) Å, <i>c</i> = 5.30170(10) Å, space group <i>P</i>6₃/<i>mcm</i>) were also obtained