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Risk prediction of common bile duct stone recurrence based on new common bile duct morphological subtypes

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World Journal of Gastrointestinal Surgery 2022年第8期14卷 874-876页

作者： Hirokazu Saito shuji Tada Department of Gastroenterology Kumamoto City HospitalKumamoto 862-8505Japan

Stones in the common bile duct(CBD) are reported worldwide, and this condition is majorly managed through endoscopic retrograde cholangiopancreatography(ERCP). CBD stone recurrence is an important issue after endoscopic stone removal. Therefore, it is essential to identify its risk factors to determine the necessity of regular follow-up in patients who underwent endoscopic removal of CBD stones. The authors identified that the S and polyline morphological subtypes of CBD were associated with increased stone recurrence. New morphological subtypes of CBD presented by the authors can be important risk predictors of recurrence after endoscopic stone removal. Furthermore, the new morphological subtypes of CBD may predict the risk of residual CBD stones or technical difficulty in CBD stone removal. Further studies with a large sample size and longer follow-up durations are warranted to examine the usefulness of the newly identified morphological subtypes of CBD in predicting the outcomes of ERCP for CBD stone removal.

关键词： Endoscopic retrograde cholangiopancreatography Common bile duct stone Stone removal Recurrence Common bile duct morphology Risk prediction

武器系统地面设备Ti-B20合金时效过程组织与性能调控研究

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贵州科学 2024年第4期42卷 86-89页

作者：韩盼盼柳书吉冀宣名江南机电设计研究所贵州贵阳550009 贵州大学材料与冶金学院贵州贵阳550025

基于武器系统地面设备对钛合金材料高强度使用的需求,开展影响Ti-B20合金力学性能的因素分析,采用金相显微镜(OM)、扫描电子显微镜(SEM)和X射线衍射(XRD)等技术研究了高压扭转变形对Ti-B20合金微观组织演变、时效行为及力学性能的影响... 详细信息

基于武器系统地面设备对钛合金材料高强度使用的需求,开展影响Ti-B20合金力学性能的因素分析,采用金相显微镜(OM)、扫描电子显微镜(SEM)和X射线衍射(XRD)等技术研究了高压扭转变形对Ti-B20合金微观组织演变、时效行为及力学性能的影响。研究结果表明,Ti-B20合金在高压扭转(N=10)变形后没有发生相变,变形方式以位错滑移为主。经过固溶处理的合金在时效过程中析出针状α相,并且其沿着晶界析出。高压扭转变形的合金中产生大量的高密度位错区域,这些区域在时效过程中作为α相的优先形核位点,最终形成分布均匀的超细α相,导致显著的析出强化。

关键词： Ti-B20合金高压扭转组织演变力学性能

100 km wear-free sliding achieved by microscale superlubric graphite/DLC heterojunctions under ambient conditions

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National Science Review 2022年第1期9卷 17-24页

作者： Deli Peng Jin Wang Haiyang Jiang shuji Zhao Zhanghui Wu Kaiwen Tian Ming Ma Quanshui Zheng Department of Engineering Mechanics Tsinghua University Center for Nano and Micro Mechanics Tsinghua University Institute of Superlubricity Technology Research Institute of Tsinghua University in Shenzhen State Key Laboratory of Tribology Tsinghua University Department of Mechanical Engineering Tsinghua University

Wear-free sliding between two contacted solid surfaces is the ultimate goal in the effort to extend the lifetime of mechanical devices,especially when it comes to inventing new types of micro-ele ctromechanical systems where wear is often a major *** we report experimental observations of wear-free sliding for a micrometer-sized graphite flake on a diamond-like-carbon(DLC) surface under ambient conditions with speeds up to 2.5 m/s,and over a distance of 100 *** coefficient of friction(COF) between the microscale graphite flake,a van der Waals(vdW) layered material and DLC,a non-vdW-layered material,is measured to be of the order of 10-3,which belongs to the superlubric *** ultra-low COFs are also demonstrated for a microscale graphite flake sliding on six other kinds of non-vdW-layered materials with sub-nanometer *** a synergistic analysis approach,we reve al the underlying mechanism to be the combination of interfacial vdW interaction,atomic-smooth interfaces and the low normal stiffness of the graphite *** features guarantee a persistent full contact of the interface with weak interaction,which contributes to the ultra-low *** with the extremely high in-plane strength of graphene,wear-free sliding is achieve *** results broaden the scope of superlubricity and promote its wider application in the future.

关键词： structural superlubricity wear-free microscale graphite DLC

pH对大黄鱼肌原纤维蛋白结构性质及乳化性的影响

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水产学报 2024年第3期48卷 164-173页

作者：任中阳崔雅清陈玉峰石林凡郝更新杨燊邱绪建刘淑集翁武银集美大学海洋食品与生物工程学院集美大学厦门市海洋功能食品重点实验室浙江工业大学浙江省深蓝渔业资源高效开发利用重点实验室浙江工业大学食品科学与工程学院福建省水产研究所

为深入探究大黄鱼肌原纤维蛋白(MP)的乳化性，以满足大黄鱼蛋白质高值化开发利用的需求。实验探究了不同pH对大黄鱼MP结构性质及其乳化性的影响。采用pH分别为2、4、6、8、10、12的低盐磷酸缓冲液处理大黄鱼MP，通过SDS-PAGE分析大黄鱼M... 详细信息

为深入探究大黄鱼肌原纤维蛋白(MP)的乳化性，以满足大黄鱼蛋白质高值化开发利用的需求。实验探究了不同pH对大黄鱼MP结构性质及其乳化性的影响。采用pH分别为2、4、6、8、10、12的低盐磷酸缓冲液处理大黄鱼MP，通过SDS-PAGE分析大黄鱼MP降解情况，利用接触角测量仪和荧光分光光度计考察其疏水性变化。将不同pH下大黄鱼MP溶液与大豆油以体积比为1∶1的比例经高速均质制备乳液，并对其乳滴电位、粒径以及乳液的乳析指数进行测定，综合分析在不同pH下乳液的稳定性。SDS-PAGE电泳结果表明，在pH 4时，大黄鱼MP条带颜色较浅，在pH 6～12时，肌球蛋白重链条带基本消失，肌动蛋白条带颜色逐渐加深，且在浓缩胶顶部出现了高分子聚集物。对接触角和荧光光谱的综合分析表明，大黄鱼MP疏水性随pH增加而增加。对不同pH下MP乳液特性分析显示，在pH 8时，乳滴带负电且Zeta电位绝对值大[(49.63±1.52) mV]、粒径较小、乳液稳定性较好，而pH 12条件下容易出现破乳，不利于乳液的稳定。在pH 8时，大黄鱼MP结构更有利于提升乳液稳定性。研究表明，在弱碱性条件下更有利于大黄鱼MP形成稳定的乳液体系。pH对大黄鱼MP结构性质和乳化性的影响探究，有望为大黄鱼MP在食品工业中的开发利用提供理论依据。

关键词：大黄鱼肌原纤维蛋白 pH 疏水性乳化性

New microbial electrosynthesis system for methane production from carbon dioxide coupled with oxidation of sulfide to sulfate

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Journal of Environmental Sciences 2023年第3期125卷 786-797页

作者： Hiromi Kambara Ha T.T.Dinh shuji Matsushita Yoshiteru Aoi Tomonori Kindaichi Noriatsu Ozaki Akiyoshi Ohashi Department of Civil and Environmental Engineering Graduate School of EngineeringHiroshima University1–4–1KagamiyamaHigashi-HiroshimaHiroshima 739–8527Japan Faculty of Environment Ho Chi Minh City University of Natural Resources and Environment236 Le Van Sy1 WardTan Binh DistrictHo Chi Minh CityVietnam Agricultural Technology Research Center Hiroshima Prefectural Technology Research Institute6869HaraHachihonmatsuHigashihiroshimaHiroshima 739–0151Japan Program of Biotechnology Graduate School of Integrated Sciences for LifeHiroshima University1–3–1KagamiyamaHigashi-HiroshimaHiroshima 739–8530Japan Department of Civil and Environmental Engineering Graduate School of Advanced Science and EngineeringHiroshima University1–4–1KagamiyamaHigashi-HiroshimaHiroshima 739–8527Japan

Microbial electrosynthesis system (MES) is a promising method that can use carbon dioxide,which is a greenhouse gas,to produce methane which acts as an energy source,without using organic ***,this bioelectrical reduction reaction can proceed at a certain high applied voltage when coupled with water oxidation in the anode coated with metallic *** coupled with the oxidation of HS–to SO_(4)^(2-),methane production is thermodynamically more feasible,thus implying its production at a considerably lower applied *** this study,we demonstrated the possibility of electrotrophic methane production coupled with HS–oxidation in a cost-effective bioanode chamber in the MES without organic substrates at a low applied voltage of 0.2 *** addition,microbial community analyses of biomass enriched in the bioanode and biocathode were used to reveal the most probable pathway for methane production from HS–*** the bioanode,electroautotrophic SO_(4)^(2-)production accompanied with electron donation to the electrode is performed mainly by the following two steps:first,incomplete sulfide oxidation to sulfur cycle intermediates (SCI) is performed;then the produced SCI are disproportionated to HS^(–)and SO_(4)^(2-).In the biocathode,methane is produced mainly via H_(2)and acetate by electronaccepting syntrophic bacteria,homoacetogens,and acetoclastic ***,a new ecofriendly MES with biological H_(2)S removal is established.

关键词： Microbial electrosynthesis system Low applied voltage Organic substrates Methane production Sulfur oxidation

Biological methane production coupled with sulfur oxidation in a microbial electrosynthesis system without organic substrates

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Journal of Environmental Sciences 2022年第6期34卷 68-78页

作者： Ha T.T.Dinh Hiromi Kambara shuji Matsushita Yoshiteru Aoi Tomonori Kindaichi Noriatsu Ozaki Akiyoshi Ohashi Department of Civil and Environmental Engineering Graduate School of Advanced Science and EngineeringHiroshima University1-4-1KagamiyamaHigashihiroshimaHiroshima 739-8527Japan Faculty of Environment Ho Chi Minh City University of Natural Resources and Environment236 Le Van Sy1 WardTan Binh DistrictHo Chi Minh CityViet Nam Agricultural Technology Research Center Hiroshima Prefectural Technology Research Institute6869HaraHachihonmatsuHigashihiroshimaHiroshima 739-0151Japan Program of Biotechnology Graduate School of Integrated Sciences for LifeHiroshima University1-3-1KagamiyamaHigashihiroshimaHiroshima 739-8530Japan

Methane is produced in a microbial electrosynthesis system(MES) without organic substrates. However, a relatively high applied voltage is required for the bioelectrical *** this study, we demonstrated that electrotrophic methane production at the biocathode was achieved even at a very low voltage of 0.1 V in an MES, in which abiotic HS-oxidized to SO_(4)^(2-) at the anodic carbon-cloth surface coated with platinum powder. In addition, microbial community analysis revealed the most probable pathway for methane production from electrons. First, electrotrophic H_(2) was produced by syntrophic bacteria, such as Syntrophorhabdus, Syntrophobacter, Syntrophus, Leptolinea, and Aminicenantales, with the direct acceptance of electrons at the biocathode. Subsequently, most of the produced H_(2) was converted to acetate by homoacetogens, such as Clostridium and Spirochaeta 2. In conclusion,the majority of the methane was indirectly produced by a large population of acetoclastic methanogens, namely Methanosaeta, via acetate. Further, hydrogenotrophic methanogens,including Methanobacterium and Methanolinea, produced methane via H_(2).

关键词： Bioelectricity Homoacetogens Methane production Microbial electrosynthesis system Sulfur oxidation

基于二次枝晶间距的差压铸造A356铝合金疲劳寿命预测

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特种铸造及有色合金 2024年第2期44卷 281-285页

作者：徐佐乔海波邱正夏书乐刘书基朱志华中信戴卡股份有限公司秦皇岛066011

差压铸件由于复杂的结构、凝固条件不均匀,其内部的二次枝晶间距分布存在较大差异,进而导致不同区域存在不同的性能。目前,产品设计阶段的有限元分析采用统一的材料疲劳性能模型,导致模拟与试验结果存在偏差。通过对差压铸件不同位置区... 详细信息

差压铸件由于复杂的结构、凝固条件不均匀,其内部的二次枝晶间距分布存在较大差异,进而导致不同区域存在不同的性能。目前,产品设计阶段的有限元分析采用统一的材料疲劳性能模型,导致模拟与试验结果存在偏差。通过对差压铸件不同位置区域进行二次枝晶间距测量和材料疲劳试验,建立了差压铸造A356铝合金的疲劳寿命、应力和二次枝晶间距的定量关系式,得到了不同二次枝晶间距对应的S-N曲线。经过试验验证,该定量关系式的预测结果与试验结果符合较好,预测疲劳寿命的对数相对误差最大绝对值在2%以下。同时,还通过扫描电镜(SEM)对材料疲劳断口进行了观察,阐述了疲劳裂纹的萌生和扩展机制。

关键词：差压铸造 A356合金二次枝晶间距疲劳性能

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极区受激电磁辐射实验研究

地球物理学报 2024年第7期67卷 2487-2495页

作者：陈靓杨巨涛何凌磊李清亮郝书吉马广林闫玉波车海琴梁勇敢李海英张文超中国电波传播研究所电波环境特性及模化技术重点实验室山东青岛266107 南阳师范学院物理与电子工程学院河南南阳473061

受激电磁辐射(stimulated electromagnetic emissions, SEE)复杂的谱线特征,为研究电离层加热物理机制提供了强有力的研究手段.本文基于2017年和2022年我国学者利用EISCAT加热系统开展电离层加热实验期间的SEE数据,分析了加热电磁波的... 详细信息

受激电磁辐射(stimulated electromagnetic emissions, SEE)复杂的谱线特征,为研究电离层加热物理机制提供了强有力的研究手段.本文基于2017年和2022年我国学者利用EISCAT加热系统开展电离层加热实验期间的SEE数据,分析了加热电磁波的极化、频率、功率以及波束指向对SEE谱线特征的影响,研究结果表明:(1)相比于非寻常波,加热波为寻常波实验期间更易观测到丰富的SEE谱线结构,如频率上移分量最大值(upshifted maximum, UM)、热窄带连续谱(thermal narrow continuum, NCth)及向下偏移最大值(downshifted maximum, DM)等;(2)加热频率由4.07 MHz增至4.10 MHz,向下偏移峰值(downshifted peak, DP)频移与加热频率呈强线性相关,当加热频率达到电子回旋倍频时,DP和DM谱消失,上混杂波的产生过程被抑制.因此,结合电离层加热过程中DP和DM谱特征可以实时快速估算加热区内电子回旋频率的大小;(3)加热功率由24 MW增至192 MW,在DM和加热频率之间出现了一种新型下移谱特征,即中间向下偏移最大值(intermediate downshifted maximum, IDM),本实验中观测到UM随功率的变化是IDM相对于加热波频率的镜像行为;(4)结合超高频非相干散射雷达联合探测发现,加热波束指向为垂直方向逆时针夹角6°时,更易激励振荡双流不稳定性的密度纯增长模式,形成更多人工密度不均匀体,从而获得更强DM谱线.

关键词：受激电磁辐射电离层加热人工沿场不均匀体振荡双流不稳定性

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含粗骨料UHPC的强度尺寸效应与性能研究

混凝土与水泥制品 2024年第5期 51-56页

作者：王军刘晓峰陈镇衫罗西余辉廖树基明阳智慧能源集团股份公司广东中山528437

研究了胶凝材料组成比例、钢纤维类型(平直型、端钩型)对含粗骨料超高性能混凝土(UHPC)强度尺寸效应、工作性和收缩性能的影响,分析了减缩剂掺量(0~2.0%)对含粗骨料UHPC收缩性能、力学性能、抗氯离子渗透性能和孔结构的影响。结果表明:... 详细信息

研究了胶凝材料组成比例、钢纤维类型(平直型、端钩型)对含粗骨料超高性能混凝土(UHPC)强度尺寸效应、工作性和收缩性能的影响,分析了减缩剂掺量(0~2.0%)对含粗骨料UHPC收缩性能、力学性能、抗氯离子渗透性能和孔结构的影响。结果表明:适当增加粉煤灰掺量有利于改善含粗骨料UHPC的工作性,降低收缩;掺入钢纤维降低了含粗骨料UHPC的工作性,但抑制了收缩,且端钩型钢纤维抑制效果更显著;掺入1%钢纤维能够有效降低含粗骨料UHPC的强度尺寸效应,且平直型钢纤维的降低效果更好;掺入减缩剂明显降低了含粗骨料UHPC的收缩,但会使抗压强度降低,总孔隙率增大,抗氯离子渗透性能变差。

关键词：含粗骨料超高性能混凝土尺寸效应钢纤维减缩剂收缩性能力学性能抗氯离子渗透性能