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Comparative study of extrudability, microstructure, and mechanical properties of AZ80 and BA53 alloys

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Journal of Magnesium and Alloys 2023年第1期11卷 249-258页

作者： Sang-Cheol Jin Jae Won Cha Jongbin go Jun Ho Bae Sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Department of Materials Science and Engineering Kyoto UniversityKyoto 606-8501Japan Advanced Metals Division Korea Institute of Materials ScienceChangwon 51508Republic of Korea

The extrudability,microstructural characteristics,and tensile properties of the Mg–5Bi–3Al(BA53)alloy are investigated herein by comparing them with those of a commercial Mg–8Al–0.5 Zn(AZ80)*** AZ80 is extruded at 400℃,severe hot cracking occurs at exit speeds of 4.5 m/min or *** contrast,BA53 is successfully extruded without any surface cracking at 400℃ and at high exit speeds of 21–40 m/*** extruded at 3 m/min(AZ80–3)and 40 m/min(BA53–40),both AZ80 and BA53 exhibited completely recrystallized microstructures with abasal ***,BA53–40 has a coarser grain structure owing to grain growth promoted by the high temperature in the deformation ***80–3 contains a continuous network of Mg_(17)Al_(12) particles along the grain boundaries,which form via static precipitation during natural air-cooling after the material exits the extrusion ***53–40 contains coarse Mg_(3)Bi_(2) particles aligned parallel to the extrusion direction along with numerous uniformly distributed fine Mg_(3)Bi_(2) ***80–3 has higher tensile strength than BA53–40 because the relatively finer grains and larger number of solute atoms in AZ80–3 result in stronger grain-boundary and solid-solution hardening effects,*** BA53 is extruded at a high temperature and extrusion speed of 400℃ and 40 m/min,respectively,the extruded material has a high tensile yield strength of 188 *** can be primarily attributed to the large particle hardening effect resulting from the numerous fine Mg_(3)Bi_(2) particles.

关键词： Mg-Bi-Al alloy Extrusion Hot cracking Second phase Tensile properties

Analysis of Oseltamivir Resistance Substitutions in Influenza Virus Glycoprotein Neuraminidase using a Lentivirus-Based Surrogate Assay System

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Virologica Sinica 2013年第2期28卷 81-91页

作者： Jennifer Tisoncik-go Katie S Cordero Lijun Rong Department of Microbiology and Immunology College of Medicine University of Illinois at Chicago Department of Microbiology University of Washington

Influenza A virus poses a great threat to global health, and oseltamivir (trade marked as Tamiflu), which targets influenza surface glycoprotein neuraminidase (NA), is used clinically as a major anti-influenza treatment. However, certain substitutions in NA can render an influenza virus resistant to this drug. In this study, using a lentiviral pseudotyping system, which alleviates the safety concerns of studying highly pathogenic influenza viruses such as avian influenza H5N1, that utilizes influenza surface glycoproteins (hemagglutinin or HA, and NA) and an HIV-core combined with a luciferase reporter gene as a surrogate assay, we first assessed the functionality of NA by measuring pseudovirion release in the absence or presence of oseltamivir. We demonstrated that oseltamivir displays a dose-dependent inhibition on NA activity. In contrast, a mutant NA (H274Y) is more resistant to oseltamivir treatment. In addition, the effects of several previously reported substitution NA mutants were examined as well. Our results demonstrate that this lentivirus-based pseudotyping system provides a quick, safe, and effective way to assess resistance to neuraminidase inhibitors. And we believe that as new mutations appear in influenza isolates, their impact on the effectiveness of current and future anti-NA can be quickly and reliably evaluated by this assay.

关键词： Influenza virus Neuraminidase (NA) Oseltamivir Drug resistance

Magneto-impedance effect in soft Fe-based nanocrystalline alloys

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Chinese Science Bulletin 1997年第3期42卷 196-199页

作者： Yang, JX Yang, XL Chen, go Hu, BY Shen, GT Jiang, KY Physics Department East China Normal University Shanghai China

IN recent years, giant magneto-resistance (GMR) effects have been observed in some binary composite systems such as multi-layered and granular films of Fe, Co, Ni and Cr, Ag, Cu and attracted considerable interest due to their potential applications in magnetic recording heads and field sensors. However, a notable GMR effect in these films always requires a strong external magnetic field at low temperature. More recently, Mohri et al. have discovered

关键词： Fe-based nanocrystalline giant magneto-impedance effect transverse magnetic field annealing.

Impact of environmental variables on spatial and seasonal internal phosphorus loading in a mesoeutrophic lake

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International Journal of Sediment Research 2019年第1期34卷 14-26页

作者： Katarzyna Kowalczewska-Madura Ryszard go?dyn Julia Bogucka Katarzyna Strzelczyk Department of Water Protection Faculty of BiologyAdam Mickiewicz University

Strzeszynskie Lake was formerly a slightly eutrophic（meso-eutrophic） water body. The aim of the current research was to define variables on both spatial and seasonal internal phosphorus loading from bottom sediments at five stations located in zones varying in depth, oxygenation, macrophyte presence,and uses of the neighboring catchment area. Ex situ experiments done with the use of intact bottom sediment cores have shown that the highest phosphorus release occurred in the deepest part of the lake and reached 3.6 mg P/m2d under anoxic conditions during summer thermal stratification. In turn, the internal loading from littoral sediments, which were well aerated all year round, was clearly ***, phosphorus accumulation in the bottom sediment was observed to reach a maximum of 1.45 mg P/m2d in autumn. A comparison of the internal loading intensity in lake zones with different land uses of the neighboring catchment area has shown slightly higher values at stations adjacent to the forest catchment area than those used for recreation. Changes in the land use of the catchment area of Strzeszynskie Lake, especially the increase in impermeable surfaces, have led to an increased inflow of external loads after heavy rains, resulting in deterioration in water quality and a delayed increase in internal loading.

关键词： Bottom sediments Interstitial water Bottom water Internal loading Sediment-water interface

Improving ionic conductivity of von-Alpen-type NASICON ceramic electrolytes via magnesium doping

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Journal of Advanced Ceramics 2023年第5期12卷 1058-1066页

作者： Il-Seop Jang Wooseok go Bo-Ye Song Hayoung Park Yun Chan Kang Jinyoung Chun Emerging Materials R&D Division Korea Institute of Ceramic Engineering and Technology(KICET)Jinju 52851Republic of Korea Department of Materials Science and Engineering Korea UniversitySeoul 02841Republic of Korea Energy Storage and Distribution Resources Division Lawrence Berkeley National LaboratoryBerkeley 94720USA

NASICON (sodium (Na) superionic conductor) compounds have attracted considerable attention as promising solid electrolyte materials for advanced Na-based batteries. In this study, we investigated the improvement in ionic conductivities of von-Alpen-type NASICON (vA-NASICON) ceramic electrolytes by introducing a magnesium ion (Mg^(2+)) as a heterogeneous element. The optimal Mg-doped vA-NASICON exhibited a high ionic conductivity of 3.64×10^(−3) S·cm^(−1), which was almost 80% higher than that of un-doped vA-NASICON. The changes in physicochemical properties of the vA-NASICONs through the Mg introduction were systematically analyzed, and their effects on the ionic conductivities of the vA-NASICON were studied in detail. When the optimal ratio of Mg^(2+) was used in a synthetic process, the relative density (96.6%) and grain boundary ionic conductivity (σgb) were maximized, which improved the total ionic conductivity (σt) of the vA-NASICON. However, when Mg^(2+) was introduced in excess, the ionic conductivity decreased because of the formation of an undesired sodium magnesium phosphate (NaxMgyPO_(4)) secondary phase. The results of this study are expected to be effectively applied in the development of advanced sodium-based solid electrolytes with high ionic conductivities.

关键词： NASICON solid electrolyte von-Alpen-type magnesium(Mg)doping ionic conductivity

Endoscopic biliary drainage for patients with unresectable pancreatic cancer with obstructive jaundice who are to undergo gemcitabine chemotherapy

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World Journal of Gastroenterology 2006年第45期12卷 7299-7303页

作者： Osamu Takasawa Naotaka Fujita go Kobayashi Yutaka Noda Kei Ito Jun Horaguchi Sendai City Medical Center Gastroenterology 5-22-1 Tsurugaya Miyaginoku Sendai Miyagi 983-0824 Japan

AIM: To assess optimum endoscopic biliary drainage (EBD) in cases with unresectable pancreatic cancer in the era of gemcitabine (GEM). METHODS: Thirty patients with unresectable pancreatic cancer, who presented with jaundice and underwent chemotherapy using GEM after EBD were included in this study (GEM group). Fifteen cases with the same clinical manifestation and stage of pancreatic cancer treated with EBD alone were also included as controls. A covered metallic stent (CMS) or a plastic stent (PS) was used for EBD. The mean survival time (MST) in each group, risk factors of survival time, type of stent used and associated survival time, occlusion rate of stent, patency period of stent, and risk factors of stent occlusion were evaluated. RESULTS: MST in the GEM group was longer than that in the control (9.9 mo vs 6.2 mo). In the GEM group, the survival time was not different between those who underwent metallic stenting and those who underwent plastic stenting. Stent occlusion occurred in 60% of the PS group and 7% of the CMS group. The median stent patency in the PS-GEM group and the CMS-GEM group was 5 mo and 7.5 mo, respectively. Use of a PS was the only risk factor of stent occlusion. CONCLUSION: A CMS is recommended in cases presenting with jaundice due to unresectable pancreatic cancer, since the use of a CMS makes it possible to continue chemotherapy using GEM without repetition of stent replacement.

关键词： Gemcitabine chemotherapy Endoscopic biliary drainage Covered metallic stent Pancreatic cancer Unresectable pancreatic cancer Obstructive jaundice

Elucidating the evolution of long-period stacking ordered phase and its effect on deformation behavior in the as-cast Mg-6Gd-1Zn-0.6Zr alloy

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Journal of Magnesium and Alloys 2023年第8期11卷 2801-2810页

作者： Sangwon Lee Yejun Park Jongbin go Young Mok Kim Seok Su Sohn Jiehua Li Pyuck-Pa Choi Department of Materials Science and Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon34141Republic of Korea Department of Materials Science and Engineering Kyoto UniversityKyoto606-8501Japan Department of Materials Science and Engineering Korea UniversitySeoul02841Republic of Korea Institute of Casting Research Montanuniverstät LeobenLeobenA-8700Austria

Herein,the evolution of long-period stacking ordered(LPSO)phases in the as-cast Mg-6Gd-1Zn-0.6Zr(wt.%)alloy are investigated via transmission electron microscopy(TEM)and atom probe tomography(APT).The TEM results reveal that two types of LPSO phase(a bulky interdendritic phase and a plate-like matrix LPSO phase)are formed in the as-cast *** of the LPSO phases are confirmed to be of the 14H type,with a smaller proportion being of the 18R ***,the APT results reveal that the composition of the interdendritic LPSO phase is closer to that of the ideal 14H phase compared to the matrix LPSO phase,and both the interdendritic and matrix LPSO phases exhibit a Gd/Zn ratio of 2.5,thereby indicating a deficient Zn content compared to the ideal 14H phase(i.e.,1.3).In addition,the influence of the LPSO phases on the deformation behavior is investigated at different compressive plastic strains using electron backscatter diffraction(EBSD)analysis to reveal twinning and slip behavior during *** results indicate that the LPSO phase induces additional work hardening in the late stage of deformation via the suppression of{1011}compressive twinning and the activation of non-basal slip systems.

关键词： Magnesium alloy Long-period stacking ordered phase Transmission electron microscopy Atom probe tomography Work hardening behavior

Relationship between post-ERCP pancreatitis and the change of serum amylase level after the procedure

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World Journal of Gastroenterology 2007年第28期13卷 3855-3860页

作者： Kei Ito Naotaka Fujita Yutaka Noda go Kobayashi Jun Horaguchi Osamu Takasawa Takashi Obana Department of Gastroenterology Sendai City Medical Center5-22-1TsurugayaMiyagino-kuSendaiMiyagi 983-0824Japan

AIM: To clarify the relationship between the change of serum amylase level and post-ERCP pancreatitis. METHODS: Between January 1999 and December 2002, 1291 ERCP-related procedures were performed. Serum amylase concentrations were measured before the procedure and 3, 6, and 24 h afterward. The frequency and severity of post-ERCP pancreatitis and the relationship between these phenomena and the change in amylase level were estimated. RESULTS: Post-ERCP pancreatitis occurred in 47 patients (3.6%). Pancreatitis occurred in 1% of patients with normal amylase levels 3 h after ERCP, and in 1%, 5%, 20%, 31% and 39% of patients with amylase levels elevated 1-2 times, 2-3 times, 3-5 times, 5-10 times and over 10 times the upper normal limit at 3 h after ERCP, respectively (level < 2 times vs ≥ 2 times, P < 0.001). Of the 143 patients with levels higher than the normal limit at 3 h after ERCP followed by elevation at 6 h, pancreatitis occurred in 26%. In contrast, pancreatitis occurred in 9% of 45 patients with a level higher than two times the normal limit at 3 h after ERCP followed by a decrease at 6 h (26% vs 9%, P < 0.05). CONCLUSION: Post-ERCP pancreatitis is frequently associated with an increase in serum amylase level greater than twice the normal limit at 3 h after ERCP with an elevation at 6 h. A decrease in amylase level at 6 h after ERCP suggests the unlikelihood of development of post-ERCP pancreatitis.

关键词： Acute pancreatitis Endoscopic retrograde cholangiopancreatography Serum amylase

Legends of the dashboard: an empirical evaluation of split and joint layout designs for geovisual analytics interfaces

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International Journal of Digital Earth 2023年第1期16卷 1395-1417页

作者： Izabela gołębiowska Tomasz Opach ArzuÇöltekin Jolanta Korycka-Skorupa Jan Ketil Rød Faculty of Geography and Regional Studies University of WarsawWarsawPoland Department of Geography Norwegian University of Science and TechnologyTrondheimNorway Institute for Interactive Technologies University of Applied Sciences and Arts Northwestern SwitzerlandWindischSwitzerland

Geodashboards are often designed with explanatory elements guiding *** elements(*** or annotations)need to be carefully designed to mitigate split attention or information integration *** this paper,we report expert interviews followed by a controlled experiment where we compare two interface designs with a focus on the split attention effect:(1)a multiple-legend layout with explanatory elements located next to each view,and(2)a single-legend layout with all explanatory elements gathered in one *** legend layouts did not affect the performance,but affected user satisfaction.75%of the participants preferred the multiple-legend layout,and rated it with a higher usability score,mainly attributing this preference to the proximity of legend elements to the view of *** tracking data strongly and clearly verifies that participants indeed make use of the proximity:With the single-legend,the majority of eye-movement transitions were between the single-legend and the closest view to the legend,whereas with multiple-legend participants have shorter and more frequent legend visits,as well as more transitions between legends and *** together,the design lesson we learned from this experiment can be summarized as‘split the legend elements,but make it close to the explained elements’.

关键词： Geodashboard layout design legend split attention user study eye tracking