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多力场耦合条件下T型圆管通道内流体热混合机理研究

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西安交通大学学报 2025年第1期59卷 78-92页

作者：李桉琦苏博林梅王秋旺西安交通大学能源与动力工程学院西安710049

针对海洋动力平台和船舶动力装置中T型圆管通道内冷热流体间的热混合机理尚不清楚的问题,利用大涡模拟方法,对不同支管布置方式高温高压工况下(运行压力为10 MPa,进口流体温差为275 K,摇摆雷诺数为41 500)的多力场耦合T型圆管通道内流... 详细信息

针对海洋动力平台和船舶动力装置中T型圆管通道内冷热流体间的热混合机理尚不清楚的问题,利用大涡模拟方法,对不同支管布置方式高温高压工况下(运行压力为10 MPa,进口流体温差为275 K,摇摆雷诺数为41 500)的多力场耦合T型圆管通道内流体热混合机理进行数值研究。利用提出的混合系数定量评价了不同布置方式下T型圆管通道内流体混合效果,利用均方根温度定量评价了不同布置方式下T型圆管通道管壁处温度脉动情况。结果表明:剪切层和尾迹区内涡结构与温度场存在时间和空间上的协同机制,且涡脱落频率和温度脉动频率基本相同,脱落频率为19.3 Hz;附加惯性力引起T型圆管通道内涡结构和温度场在时间和空间上周期性变化,加速了流体混合过程,削弱了浮升力和重力引起的热分层现象,同时增大了流体域内温度波动,长度约为10.2 D(D为主管内径);与对应的静止工况相比,支管竖直向上、水平和竖直向下布置时,摇摆条件下混合系数分别增大了10.8%、18.3%和27.8%;摇摆条件竖直向下布置时,管壁处温度均方根峰值最大为0.16,约为静止工况的2倍。因此,支管竖直向上布置时,热混合效果最好,热分层现象最弱,在实际应用中应被优先考虑。

关键词： T型圆管通道浮升力摇摆条件热混合机理大涡模拟

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新型抗癫痫发作药物吡仑帕奈添加治疗0~18岁儿童难治性癫痫的临床观察研究

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中国全科医学 2025年第2期28卷 250-256页

作者：马湖萍任蓉侯梅苑爱云青岛大学附属妇女儿童医院神经康复科山东省青岛市266034 山东省潍坊市寿光市人民医院新生儿科 262700

背景目前儿童难治性癫痫(RE)仍是癫痫的治疗难点,国内吡仑帕奈(PER)治疗儿童RE尚属新药,缺少PER对儿童RE添加治疗的建议,且国内报道中使用PER治疗的RE患儿样本量较少。因此PER对于儿童RE,尤其低年龄RE患儿的疗效仍需大样本、进一步研究... 详细信息

背景目前儿童难治性癫痫(RE)仍是癫痫的治疗难点,国内吡仑帕奈(PER)治疗儿童RE尚属新药,缺少PER对儿童RE添加治疗的建议,且国内报道中使用PER治疗的RE患儿样本量较少。因此PER对于儿童RE,尤其低年龄RE患儿的疗效仍需大样本、进一步研究。目的探究PER添加治疗儿童RE的疗效、可能的适应证、不良反应及耐受性。方法对2022年1月—2023年1月在青岛大学附属妇女儿童医院诊治的0~18岁RE患儿进行自身对照、回顾性分析,对比PER添加治疗前后不同观察时点的癫痫发作频率的变化,评估PER的治疗效果,记录药物不良反应及药物保留率,并分析PER有效组与无效组的临床特征。结果共纳入192例研究对象,PER添加治疗后,第12、24、36周的有效率分别为56.3%(108/192)、62.1%(113/182)、69.7%(122/175),无发作率分别为19.3%(37/192)、21.4%(39/182)、24.6%(43/175)。不良反应发生率为16.1%(31/192),主要为头晕、暴躁易怒、无力嗜睡等,末次随访药物保留率为91.1%(175/192)。PER添加治疗的RE患儿连续用药12周时,治疗总有效与无效/恶化患儿起病年龄、抗癫痫治疗病程、起源类型、发作形式、添加PER前发作频率、联合其他抗癫痫发作药物(ASMs)数量、生酮饮食/外科治疗情况,差异有统计学意义(P<0.05)。此外,178例患儿进行了脑电图检查,167例患儿进行了头颅磁共振检查;治疗总有效与无效/恶化患儿脑电图检查结果、头颅磁共振检查结果比较,差异有统计学意义(P<0.05)。脑电图检查结果中以脑前部(前、中、颞前、中部)放电总有效占比较高;头颅影像学检查结果中以正常者总有效占比较高,其次为以脑白质损伤为主的患儿。结论PER添加治疗儿童RE整体有效率及保留率较高,不良反应轻微,药物耐受情况好。对于起病年龄晚、发作形式为运动性发作、局灶性起源、抗癫痫治疗病程短、联合用药数量及发作频率少的RE患儿更为有效。脑电图中以脑前部(前、中、颞前、颞中部)放电、头颅磁共振结果正常者总有效占比较高。

关键词：难治性癫痫儿童吡仑帕奈治疗结果药物不良反应

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Sediment discharge of the Yellow River, China: past, present and future——A synthesis

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Acta Oceanologica Sinica 2015年第2期34卷 1-8页

作者： ren mei'e Key Laboratory of Coast and Island Development of Ministry of Education School of Geographic and Oceanographic Sciences Nanjing University

The Yellow River cut through Sanmenxia Gorge and discharged into the sea via the North China Plain in 150 ka BP; since then, around 86 000 × 108 t sediment has been transported passing Sanmenxia Gorge. Based on land use and land cover changes in Loess Plateau and other available evidence, an estimate of the Yellow River sediment budget is presented here： about 72% of the sedimentary material was trapped in the North China Plain and the remainder（i.e., 26%） escaped to the sea. At the present stage, 〈 0.2×108 t/a suspended sediment of the Yellow River enter the northern Yellow Sea. The transport pattern is determined mainly by the shelf current system. Annually 0.2×108–0.3×108 t of suspended particles are carried to the East China Sea; the materials are derived mainly from coastal and subaqueous delta erosion associated with the abandoned Yellow River on the Jiangsu coast. Since 1972, the lower Yellow River started to have a situation of continuous no-flow. During 1996–2000, the annual water flow and sediment discharge are only 19%, as compared with normal years（i.e., average for 1950–1979）. In response to global warming and increase of water diversion from the Yellow River for industrial and urban use, the sediment flux of the Yellow River to the sea will most likely remain small in the next two to three decades.

关键词： Yellow River Loess Plateau sediment budget transport patterns sediment retention

Cu-catalyzed enantioselective cyanation of benzylic C–H via radical relay

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Science Bulletin 2016年第23期61卷 1791-1792页

作者： Yuxi ren Weiping su State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

The transition metal catalyzed C-H bond functionalization of hydrocarbons has aroused great interests in recent years due to the potential opportunity of developing novel methodologies in synthesis and chemical proces... 详细信息

关键词：继电器不对称铜催化氰化苄基过渡金属催化碳氢化合物化学过程

HEAVY BALL FLEXIBLE GMRES METHOD FOR NONSYMMETRIC LINEAR SYSTEMS

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Journal of Computational Mathematics 2022年第5期40卷 711-727页

作者： mei Yang ren-Cang Li School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240China Department of Mathematics University of Texas at ArlingtonArlingtonTXUSA

Flexible GMRES(FGMRES)is a variant of preconditioned GMRES,which changes preconditioners at every Arnoldi *** often has to be restarted in order to save storage and reduce orthogonalization cost in the Arnoldi *** restarted GMRES,FGMRES may also have to be restarted for the same reason.A major disadvantage of restarting is the loss of convergence *** this paper,we present a heavy ball flexible GMRES method,aiming to recoup some of the loss in convergence speed in the restarted flexible GMRES while keep the benefit of limiting memory usage and controlling orthogonalization *** tests often demonstrate superior performance of the proposed heavy ball FGMRES to the restarted FGMRES.

关键词： GMRES Flexible GMRES Heavy ball GMRES Preconditioner Linear system.

A Special Two-Soliton Solution of sine-Gordon Equation

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Communications in Theoretical Physics 2005年第1期43卷 9-12页

作者： AOSheng-mei YANJia-ren DepartmentofPhysics HunanNormalUniversityChangsha410081China

A special two-soliton solution of sine-Gordon equation is obtained by using the Hirota direct method. It is shown in a mass-centre system how two kinks move and interact with each other.

关键词： soliton sine-Gordon equation Hirota direct method kink

阿戈美拉汀缓解APP/PS1转基因小鼠焦虑及抑郁样行为的机制

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中国组织工程研究 2025年第6期29卷 1176-1182页

作者：李甜任俞桦高艳萍苏强山西医科大学基础医学院生理学系细胞生理学教育部重点实验室细胞生理学山西省重点实验室山西省太原市030001 山西医科大学汾阳学院医学检验系山西省汾阳市032200

背景:阿戈美拉汀在临床上用于治疗焦虑、抑郁等相关精神行为异常。前期研究证实,阿戈美拉汀能够有效缓解阿尔茨海默病模型小鼠的认知行为、海马突触可塑性及脑病理特征,然而阿戈美拉汀能否改善阿尔茨海默病模型小鼠的焦虑和抑郁样行为... 详细信息

背景:阿戈美拉汀在临床上用于治疗焦虑、抑郁等相关精神行为异常。前期研究证实,阿戈美拉汀能够有效缓解阿尔茨海默病模型小鼠的认知行为、海马突触可塑性及脑病理特征,然而阿戈美拉汀能否改善阿尔茨海默病模型小鼠的焦虑和抑郁样行为仍不清楚。目的:探究阿戈美拉汀对APP/PS1(阿尔茨海默病)转基因小鼠焦虑和抑郁样行为的改善效应及分子机制。方法:①将18只APP/PS1转基因小鼠随机分为模型对照组(n=9)、模型干预组(n=9),将18只野生型小鼠随机分为对照组(n=9)、干预组(n=9),模型干预组与干预组小鼠腹腔注射阿戈美拉汀10 mg/(kg·d),连续注射31 d后进行高架十字迷宫、强迫游泳行为学实验与海马组织mRNA测序。②取小鼠海马神经元细胞株(HT22)、脑微血管内皮细胞株(bEnd.3),分别分4组培养:空白组不加入任何药物,药物组加入20µmol/L阿戈美拉汀,模型组加入10µmol/Lβ-淀粉样蛋白1-42,实验组加入10µmol/Lβ-淀粉样蛋白1-42+20µmol/L阿戈美拉汀,培养24 h后,免疫印迹检测HT22细胞S416p-tau和S9p-GSK3β的蛋白表达,免疫印迹检测bEnd.3细胞低密度脂蛋白受体相关蛋白1、糖基化终产物受体的蛋白表达。结果与结论:①在高架十字迷宫实验中,模型对照组小鼠的探索开放臂时间与开放臂进入次数均少于对照组(P<0.05),模型干预组小鼠的探索开放臂时间与开放臂进入次数均多于模型对照组(P<0.05);在强迫游泳测试中,模型对照组小鼠的不动时间长于对照组(P<0.05),模型干预组小鼠的不动时间短于模型对照组(P<0.05);海马组织mRNA测序显示,阿戈美拉汀可以增强APP/PS1小鼠海马区低密度脂蛋白受体相关蛋白1的表达。②免疫印迹检测显示,模型组HT22细胞S416p-tau蛋白表达高于空白组(P<0.05),实验组HT22细胞S416p-tau蛋白表达低于模型组(P<0.05),药物组HT22细胞S9p-GSK3β蛋白表达高于空白组(P<0.05),实验组HT22细胞S9p-GSK3β蛋白表达高于模型组(P<0.05),实验组bEnd.3细胞低密度脂蛋白受体相关蛋白1蛋白表达高于模型组(P<0.05)。③结果表明,阿戈美拉汀可通过促进脑内β-淀粉样蛋白和tau的清除来缓解阿尔茨海默病小鼠的焦虑和抑郁样行为。

关键词：阿尔茨海默病阿戈美拉汀 APP/PS1转基因小鼠焦虑抑郁

The contrast between defect solitons in parity-time symmetric superlattice and simple-lattice complex potentials

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Chinese Physics B 2012年第2期21卷 362-367页

作者： Hu su-mei Hu Wei Laboratory of Photonic Information Technology South China Normal UniversityGuangzhou 510631China Department of Physics Guangdong University of Petrochemical TechnologyMaoming 525000China

The existence and stability of defect superlattice solitons in parity-time （PT） symmetric superlattice and simplelattice complex potentials are reported. Compared with defect simple-lattice solitons in similar potentials, the defect soliton in superlattice has a wider stable range than that in simple-lattice. The solitons＇ power increases with increasing propagation constant. For the positive defect, the solitons are stable in the whole region where solitons exist in the semi-infinite gap. For the zero defect, the solitons are unstable at the edge of the band. For the negative defect, the solitons propagate with the shape of Y at low propagation constant and propagate stably at the large one.

关键词： defect superlattice solitons parity time symmetry

Hybrid quantum key distribution network

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Science China(Information Sciences) 2022年第10期65卷 24-30页

作者： Siyu ren Yu WANG Xiaolong su State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-Electronics Collaborative Innovation Center of Extreme Optics Shanxi University State Key Laboratory of Cryptology

Quantum key distribution(QKD) is now moving toward a scalable and secure QKD network,which establishes secret keys among network users. The continuous-variable(CV) and discrete-variable(DV)QKD systems are currently being developed in parallel and are all used in QKD networks. We propose here a hybrid QKD network, in which the CV QKD system is used to build metropolitan QKD networks, and the DV QKD system is used to connect metropolitan QKD networks. The hybrid QKD network takes advantage of high secret key rates for CV QKD systems and long distance for DV QKD systems. We also present a feasible hybrid measurement-device-independent(MDI) QKD network, which combines both CV and DV MDI QKD systems. The presented hybrid QKD networks meet the low cost and compact requirement of a realistic QKD network and provide a feasible solution for future real QKD networks by combining the advantages of both CV and DV QKD systems.

关键词： quantum network quantum key distribution hybrid quantum information continuous variable discrete variable