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构建GPT大模型的经济循环体系:理论框架与发展路径 被引量:1
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作者 杨望 徐慧琳 王钰淇 《新疆师范大学学报(哲学社会科学版)》 北大核心 2024年第3期73-85,共13页
数字技术的爆发式增长及其与实体经济的深度融合,为推动中国经济高质量发展提供了强大动能,成为促进生产方式变革和经济结构变迁的主要力量。GPT大模型作为新一代人工智能技术,具有强大的自然语言处理能力,将持续对经济增长、生产效率... 数字技术的爆发式增长及其与实体经济的深度融合,为推动中国经济高质量发展提供了强大动能,成为促进生产方式变革和经济结构变迁的主要力量。GPT大模型作为新一代人工智能技术,具有强大的自然语言处理能力,将持续对经济增长、生产效率、要素分配等各方面产生深刻影响。文本试图通过构建GPT大模型的经济循环体系、GPT大模型在国内外经济循环中发挥作用的理论框架以及GPT大模型的经济循环体系的发展路径,揭示GPT大模型经济循环体系的作用机制,为实体产业应用GPT大模型实现提质增效、助力经济高质量发展提供现实启示和参考依据。 展开更多
关键词 GPT大模型 人工智能 经济循环体系
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经方治疗良性前列腺增生症的研究进展
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作者 张琳 王杨 +1 位作者 刘铭泽 王振亮 《Chinese Medicine and Natural Products》 CAS 2024年第1期18-23,I0014-I0018,共11页
正气不足、瘀血留结、水饮停留为良性前列腺增生症(benign prostate hyperplasia,BPH)发病的主要病机。正气不足为BPH发病之根本,以金匮肾气丸、真武汤化生肾气、温阳利水;瘀血留结是BPH发病的关键病机,以桂枝茯苓丸、抵当汤以化瘀消瘢... 正气不足、瘀血留结、水饮停留为良性前列腺增生症(benign prostate hyperplasia,BPH)发病的主要病机。正气不足为BPH发病之根本,以金匮肾气丸、真武汤化生肾气、温阳利水;瘀血留结是BPH发病的关键病机,以桂枝茯苓丸、抵当汤以化瘀消瘢、利窍通便;水饮停留为BPH最为紧急之症,治以五苓散、当归芍药散以化气利水,解标症之急。 展开更多
关键词 良性前列腺增生症 金匮肾气丸 真武汤 桂枝茯苓丸 抵当汤 五苓散 当归芍药散
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新型热处理方法制备超高强度Inconel 718合金
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作者 冉蓉 王洋 +5 位作者 任富强 张元祥 方烽 张维娜 袁国 王国栋 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第7期2204-2218,共15页
为改善Inconel718合金的组织并优化性能,提出一种980℃,1 min高温超短退火和随后的双时效相结合的新型热处理方法。结果表明,超短退火处理产生了部分再结晶组织,KAM图表明即使在变形晶粒中也形成了再结晶晶核。因此,高温超短退火克服了... 为改善Inconel718合金的组织并优化性能,提出一种980℃,1 min高温超短退火和随后的双时效相结合的新型热处理方法。结果表明,超短退火处理产生了部分再结晶组织,KAM图表明即使在变形晶粒中也形成了再结晶晶核。因此,高温超短退火克服了再结晶势垒,使得后续的再结晶过程可以在较低温度的时效处理过程中完成,从而获得了均匀细化的组织(~3.59μm)。980-1min-aged样品具有优异的拉伸性能,室温极限强度和总伸长率分别为1600 MPa和19%。650℃热拉伸条件下的极限强度和伸长率分别约为1350 MPa和26%。因此,高温超短退火能有效提高Inconel718合金的性能。 展开更多
关键词 Inconel 718合金 超高强度 δ相析出相 再结晶行为 时效处理
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剪切型阻尼器增强大头榫节点模型试验研究
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作者 杨旺 高永林 +2 位作者 陶忠 赵党书 苏何先 《西安建筑科技大学学报(自然科学版)》 北大核心 2024年第4期525-534,共10页
中国传统木结构建筑破坏主要由榫卯节点松动、变形及拔榫引起.为解决榫卯节点容易松动、变形及拔榫破坏问题,引入节点阻尼器技术,在传统木结构建筑榫卯节点处安装扇形剪切型阻尼器.为研究传统木结构典型节点大头榫安装阻尼器后的抗震性... 中国传统木结构建筑破坏主要由榫卯节点松动、变形及拔榫引起.为解决榫卯节点容易松动、变形及拔榫破坏问题,引入节点阻尼器技术,在传统木结构建筑榫卯节点处安装扇形剪切型阻尼器.为研究传统木结构典型节点大头榫安装阻尼器后的抗震性能及增强效果,设计制作了6个大头榫足尺节点模型,其中3个榫卯节点未装阻尼器,3个榫卯节点安装阻尼器.通过低周反复加载试验研究6个试验模型的滞回特性、骨架曲线、刚度退化曲线及等效黏滞阻尼系数变化规律.研究结果表明:安装阻尼器可以有效控制节点的拔榫破坏;同时有效增强节点耗能、强度及刚度;安装阻尼器节点模型的极限承载力是未安装节点模型的1.5~3.5倍. 展开更多
关键词 大头榫节点 抗震性能 阻尼器 低周反复加载试验
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The Roadmap of 2D Materials and Devices Toward Chips 被引量:3
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作者 Anhan Liu Xiaowei Zhang +16 位作者 Ziyu Liu Yuning Li Xueyang Peng Xin Li Yue Qin Chen Hu Yanqing Qiu Han Jiang yang wang Yifan Li Jun Tang Jun Liu Hao Guo Tao Deng Songang Peng He Tian Tian‑Ling Ren 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期343-438,共96页
Due to the constraints imposed by physical effects and performance degra certain limitations in sustaining the advancement of Moore’s law.Two-dimensional(2D)materials have emerged as highly promising candidates for t... Due to the constraints imposed by physical effects and performance degra certain limitations in sustaining the advancement of Moore’s law.Two-dimensional(2D)materials have emerged as highly promising candidates for the post-Moore era,offering significant potential in domains such as integrated circuits and next-generation computing.Here,in this review,the progress of 2D semiconductors in process engineering and various electronic applications are summarized.A careful introduction of material synthesis,transistor engineering focused on device configuration,dielectric engineering,contact engineering,and material integration are given first.Then 2D transistors for certain electronic applications including digital and analog circuits,heterogeneous integration chips,and sensing circuits are discussed.Moreover,several promising applications(artificial intelligence chips and quantum chips)based on specific mechanism devices are introduced.Finally,the challenges for 2D materials encountered in achieving circuit-level or system-level applications are analyzed,and potential development pathways or roadmaps are further speculated and outlooked. 展开更多
关键词 Two-dimensional materials ROADMAP Integrated circuits Post-Moore era
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Insights on advanced substrates for controllable fabrication of photoanodes toward efficient and stable photoelectrochemical water splitting 被引量:1
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作者 Huilin Hou Gang Shao +2 位作者 yang wang Wai‐Yeung Wong Weiyou yang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期164-221,共58页
Conversion of solar energy into H_(2) by photoelectrochemical(PEC)water splitting is recognized as an ideal way to address the growing energy crisis and environmental issues.In a typical PEC cell,the construction of p... Conversion of solar energy into H_(2) by photoelectrochemical(PEC)water splitting is recognized as an ideal way to address the growing energy crisis and environmental issues.In a typical PEC cell,the construction of photoanodes is crucial to guarantee the high efficiency and stability of PEC reactions,which fundamentally rely on rationally designed semiconductors(as the active materials)and substrates(as the current collectors).In this review work,we start with a brief introduction of the roles of substrates in the PEC process.Then,we provide a systematic overview of representative strategies for the controlled fabrication of photoanodes on rationally designed substrates,including conductive glass,metal,sapphire,silicon,silicon carbide,and flexible substrates.Finally,some prospects concerning the challenges and research directions in this area are proposed. 展开更多
关键词 hydrogen PHOTOANODE PHOTOELECTROCHEMICAL SUBSTRATES water splitting
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高强度耐低温离子水凝胶的制备及在摩擦纳米发电机中的应用
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作者 王洋 刘文博 +2 位作者 杨宇 姜炜坤 吕高金 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2024年第5期125-133,共9页
摩擦纳米发电机(TENG)作为一种新型可持续的能量收集设备,具有自供电、高输出、低成本、灵活性和轻量化等优点。然而,传统TENG的电极材料为金属薄膜、碳片和液态金属等,存在可拉伸性差、导电性差且在低温无法工作等缺点。文中将氯化锌(Z... 摩擦纳米发电机(TENG)作为一种新型可持续的能量收集设备,具有自供电、高输出、低成本、灵活性和轻量化等优点。然而,传统TENG的电极材料为金属薄膜、碳片和液态金属等,存在可拉伸性差、导电性差且在低温无法工作等缺点。文中将氯化锌(ZnCl_(2))、磺基甜菜碱(SBMA)、纳米纤维素(CNC)和柠檬酸(CA)引入聚丙烯酸(AA)基体中,制备了具有优异力学性能(拉伸强度2.16 MPa、断裂伸长率382%)、抗疲劳性、导电性能(9.3 mS/cm)、抗冻性能(-75℃)和保水性能的离子水凝胶材料。基于该离子水凝胶所制备的TENG具有良好的可拉伸性、抗冻性(-50℃)和稳定的输出电压(60 V),能够将人体运动产生的机械能转化为电能,并成功点亮了39个LED灯。因此该水凝胶基TENG在能量收集领域展示出巨大的发展潜力,具有广阔的应用前景。 展开更多
关键词 纳米纤维素 柠檬酸 磺基甜菜碱 氯化锌 摩擦纳米发电机
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Bifunctional TiO_(2-x)nanofibers enhanced gel polymer electrolyte for high performance lithium metal batteries 被引量:1
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作者 Yixin Wu Zhen Chen +6 位作者 yang wang Yu Li Chunxing Zhang Yihui Zhu Ziyu Yue Xin Liu Minghua Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期437-448,I0011,共13页
Exploration of advanced gel polymer electrolytes(GPEs)represents a viable strategy for mitigating dendritic lithium(Li)growth,which is crucial in ensuring the safe operation of high energy density Li metal batteries(L... Exploration of advanced gel polymer electrolytes(GPEs)represents a viable strategy for mitigating dendritic lithium(Li)growth,which is crucial in ensuring the safe operation of high energy density Li metal batteries(LMBs).Despite this,the application of GPEs is still hindered by inadequate ionic conductivity,low Li^(+)transference number,and subpar physicochemical properties.Herein,Ti O_(2-x)nanofibers(NF)with oxygen vacancy defects were synthesized by a one-step process as inorganic fillers to enhance the thermal/mechanical/ionic-transportation performances of composite GPEs.Various characterizations and theoretical calculations reveal that the oxygen vacancies on the surface of Ti O_(2-x)NF accelerate the dissociation of Li PF_6,promote the rapid transfer of free Li^(+),and influence the formation of Li F-enriched solid electrolyte interphase.Consequently,the composite GPEs demonstrate enhanced ionic conductivity(1.90m S cm^(-1)at room temperature),higher lithium-ion transference number(0.70),wider electrochemical stability window(5.50 V),superior mechanical strength,excellent thermal stability(210℃),and improved compatibility with lithium,resulting in superior cycling stability and rate performance in both Li||Li,Li||Li Fe PO_(4),and Li||Li Ni_(0.8)Co_(0.1)Mn_(0.1)O_(2)cells.Overall,the synergistic influence of nanofiber morphology and enriched oxygen vacancy structure of fillers on electrochemical properties of composite GPEs is comprehensively investigated,thus,it is anticipated to shed new light on designing high-performance GPEs LMBs. 展开更多
关键词 Nanofibers fillers Oxygen vacancies Gel polymer electrolytes Lithium metal batteries
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Thermo-hydro-mechanical (THM) coupled simulation of the land subsidence due to aquifer thermal energy storage (ATES) system in soft soils 被引量:1
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作者 yang wang Fengshou Zhang Fang Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期1952-1966,共15页
Aquifer thermal energy storage(ATES)system has received attention for heating or cooling buildings.However,it is well known that land subsidence becomes a major environmental concern for ATES projects.Yet,the effect o... Aquifer thermal energy storage(ATES)system has received attention for heating or cooling buildings.However,it is well known that land subsidence becomes a major environmental concern for ATES projects.Yet,the effect of temperature on land subsidence has received practically no attention in the past.This paper presents a thermo-hydro-mechanical(THM)coupled numerical study on an ATES system in Shanghai,China.Four water wells were installed for seasonal heating and cooling of an agriculture greenhouse.The target aquifer at a depth of 74e104.5 m consisted of alternating layers of sand and silty sand and was covered with clay.Groundwater level,temperature,and land subsidence data from 2015 to 2017 were collected using field monitoring instruments.Constrained by data,we constructed a field scale three-dimensional(3D)model using TOUGH(Transport of Unsaturated Groundwater and Heat)and FLAC3D(Fast Lagrangian Analysis of Continua)equipped with a thermo-elastoplastic constitutive model.The effectiveness of the numerical model was validated by field data.The model was used to reproduce groundwater flow,heat transfer,and mechanical responses in porous media over three years and capture the thermo-and pressure-induced land subsidence.The results show that the maximum thermoinduced land subsidence accounts for about 60%of the total subsidence.The thermo-induced subsidence is slightly greater in winter than that in summer,and more pronounced near the cold well area than the hot well area.This study provides some valuable guidelines for controlling land subsidence caused by ATES systems installed in soft soils. 展开更多
关键词 Aquifer thermal energy storage(ATES) Land subsidence TOUGH-FLAC3D Thermo-elastoplastic constitutive model
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交联聚醚破乳剂对胜利油田二元驱采出液破乳性能研究
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作者 孙立梅 何海峰 +4 位作者 安申法 栾智勇 孙鹏 王阳 严峰 《日用化学工业(中英文)》 CAS 北大核心 2024年第7期795-802,共8页
针对胜利油田二元驱采出液存在的破乳困难问题,将脱水型聚醚破乳剂(BP01,TA01和PA08)与清水型聚醚破乳剂(PEI01)交联,制备出交联聚醚破乳剂D-BP,D-TA和D-PA,研究了交联聚醚破乳剂的界面活性和对油水界面膜强度的影响,以及对二元驱采出... 针对胜利油田二元驱采出液存在的破乳困难问题,将脱水型聚醚破乳剂(BP01,TA01和PA08)与清水型聚醚破乳剂(PEI01)交联,制备出交联聚醚破乳剂D-BP,D-TA和D-PA,研究了交联聚醚破乳剂的界面活性和对油水界面膜强度的影响,以及对二元驱采出液的破乳效果。结果表明,在三种交联聚醚破乳剂中,具有超支化结构的D-PA在油水界面上的吸附作用力最强,界面活性最高;D-PA对稀释原油与采出水油水界面膜的影响最大,其吸附在油水界面后形成的界面膜的扩张模量最低。D-PA破乳剂对W/O乳状液的脱水率达到94.4%,对O/W乳状液的除油率达到98.1%。更为重要的是,其能同步处理含W/O和O/W复杂乳状液。D-PA对含W/O和O/W复杂乳状液的综合脱水率高于98%,处理后污水含油低于30 mg/L,游离态聚合物保留率达到了94.8%,油水界面整齐,无乳化中间层,表现出良好的破乳效果。 展开更多
关键词 二元驱采出液 交联聚醚破乳剂 破乳 聚合物
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可降解的Mg-1%Ca合金抑制宫颈癌细胞体外增殖、迁移及侵袭
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作者 欧阳云珊 曹玲玲 +2 位作者 杨旺 赵倩 林晨 《新疆医科大学学报》 CAS 2024年第10期1321-1328,共8页
目的研究Mg-1%Ca合金的降解性能及对宫颈癌细胞体外增殖、细胞周期及迁移、侵袭的作用。方法检测Mg-1%Ca合金在DMEM培养基中pH值及Mg^(2+)、Ca^(2+)浓度的变化。根据GB/T 16886.5标准制备浸提液,取宫颈癌细胞(SiHa/HeLa),与Mg-1%Ca合金... 目的研究Mg-1%Ca合金的降解性能及对宫颈癌细胞体外增殖、细胞周期及迁移、侵袭的作用。方法检测Mg-1%Ca合金在DMEM培养基中pH值及Mg^(2+)、Ca^(2+)浓度的变化。根据GB/T 16886.5标准制备浸提液,取宫颈癌细胞(SiHa/HeLa),与Mg-1%Ca合金浸提液共培养,CCK-8法检测细胞存活率,平板克隆实验检测细胞增殖,流式细胞术分析细胞周期,划痕和Transwell侵袭实验检测细胞迁移和侵袭能力。取人宫颈上皮永生化细胞H8,与Mg-1%Ca合金浸提液共培养,CCK-8法检测细胞存活率。结果随着浸泡时间的延长,Mg-1%Ca合金浸提液和纯Mg浸提液的pH值均逐渐升高。Mg-1%Ca合金浸提液在24、72、168 h的pH值分别为(7.95±0.04)、(8.15±0.04)和(8.24±0.06),均低于纯Mg浸提液的pH值(P<0.001)。浸提24 h时,Mg-1%Ca合金浸提液中Mg^(2+)浓度增加至(21.642±0.348)mmol/L,但低于纯Mg浸提液中Mg^(2+)浓度(P<0.001)。浸提24 h时,Mg-1%Ca合金浸提液和纯Mg浸提液中的Ca^(2+)浓度都是降低的,分别为(0.431±0.065)mmol/L和(0.403±0.055)mmol/L。Mg-1%Ca合金可明显抑制宫颈癌细胞(SiHa/HeLa)的增殖,宫颈癌细胞SiHa/HeLa存活率均<70%。Mg-1%Ca合金浸提液对H8细胞有一定抑制作用,但H8细胞存活率>70%。Mg-1%Ca合金明显减少SiHa/HeLa细胞的克隆形成数(P<0.001),增加SiHa/HeLa细胞处于G0/G1期的细胞数(P<0.01),减少SiHa/HeLa细胞迁移距离(P<0.001)和侵袭细胞数(P<0.05)。Mg-1%Ca合金浸提液与纯Mg浸提液相比,对两种宫颈癌细胞的抑制作用无明显差别。结论Mg-1%Ca合金降解速率更慢,具有良好的生物相容性。Mg-1%Ca合金可抑制宫颈癌细胞(SiHa/HeLa)的体外增殖,调控G0/G1期细胞周期阻滞,并能抑制其发生迁移和侵袭。这种抑制的机制可能与微环境中Mg^(2+)浓度和pH值升高有关。 展开更多
关键词 生物可降解金属 镁合金 宫颈癌 细胞生物学行为
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新疆果园绿肥混合播种机排种器仿真试验研究
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作者 陈云生 杨旺 +3 位作者 田纪亚 廖结安 赵劲飞 孙登勋 《农机化研究》 北大核心 2024年第9期157-165,共9页
现阶段,我国新疆主干型果园进行行间绿肥播种时机械设备与作业环境适配性差,导致播种效果欠佳。为此,对播种部件进行针对性设计,运用EDEM软件对燕麦种子运动状态进行仿真分析模拟,对结果使用Origin软件中LogisticCum模型进行排种轴转速... 现阶段,我国新疆主干型果园进行行间绿肥播种时机械设备与作业环境适配性差,导致播种效果欠佳。为此,对播种部件进行针对性设计,运用EDEM软件对燕麦种子运动状态进行仿真分析模拟,对结果使用Origin软件中LogisticCum模型进行排种轴转速和排种轴工作长度与排种量之间的非线性拟合,确定函数关系,拟合结果R^(2)值为0.99535,具有统计学意义。运用Fluent软件对气吸式排种器进行模拟分析,确定圆盘厚度为2mm、转速为2r/min、型孔数量为20、气吸室负压为2kPa、型孔直径为1.5mm时各部位气流参数。模拟结果满足苜蓿种子播种条件且与理论计算结果相符。通过田间试验验证,结果符合绿肥混合播种要求,验证了仿真软件对排种部件进行模拟设计的可行性。 展开更多
关键词 混合播种机 FLUENT 气吸排种器 仿真 EDEM
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血栓弹力图联合血栓前分子标志物对弥散性血管内凝血的早期诊断价值研究
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作者 杨旺 汤晓霞 +1 位作者 胡聪 李龙平 《中国医药科学》 2024年第15期186-189,共4页
目的探讨血栓弹力图(TEG)联合血栓前分子标志物对弥散性血管内凝血(DIC)的早期诊断价值。方法选取2022年12月至2023年12月益阳市中心医院重症医学科收治的100例疑似DIC患者进行回顾性分析,根据中国弥散性血管内凝血诊断积分系统(CDSS)... 目的探讨血栓弹力图(TEG)联合血栓前分子标志物对弥散性血管内凝血(DIC)的早期诊断价值。方法选取2022年12月至2023年12月益阳市中心医院重症医学科收治的100例疑似DIC患者进行回顾性分析,根据中国弥散性血管内凝血诊断积分系统(CDSS)分为非显性DIC组和显性DIC组。比较两组TEG参数凝血反应时间(R值)、最终强度(MA值)、凝血形成时间(K值)、凝血形成速率(α角)及血栓前分子标志物血栓调节蛋白(TM)、纤溶酶-α2纤溶酶抑制物复合物(PIC)、凝血酶-抗凝血酶复合物(TAT)水平;采用Pearson线性相关分析血栓前分子标志物与TEG参数相关性;运用受试者工作特征(ROC)曲线对血栓前分子标志物、TEG参数及其联合检测进行诊断效能评估。结果显性DIC组患者R值、K值大于非显性DIC组,TAT、TM、PIC水平高于非显性DIC组,而α角、MA值均小于非显性DIC组,差异有统计学意义(P<0.05);显性DIC组患者K值、R值与TAT、TM、PIC呈正相关,而MA值、α角与TAT、TM、PIC呈负相关(P<0.05);TEG参数联合检测和血栓前分子标志物联合检测时曲线下面积分别为0.818和0.841,TEG参数和血栓前分子标志物联合检测时曲线下面积为0.914,灵敏度为90.5%,特异度为98.86%。结论血栓前分子标志物与TEG参数之间存在相关性,且TEG参数与分子标志物联合应用,在诊断早期DIC方面较单独检测更具评估价值,适合临床广泛推广。 展开更多
关键词 弥散性血管内凝血 血栓前分子标志物 血栓弹力图 评估价值
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混凝土框架结构改造型式在海塘加固中的应用研究 被引量:1
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作者 杨望 邹战军 朱杰骅 《水利水电快报》 2024年第1期52-57,共6页
在浙江“海塘安澜工程”建设过程中,为了使海塘加固满足工程自身稳定性需求,同时兼顾对周边生态环境,提出了一种新型海塘改造形式——混凝土框架结构。结合浙江东部健跳塘提升改造工程,分析了结构作用机理,对工程稳定性进行了计算,并结... 在浙江“海塘安澜工程”建设过程中,为了使海塘加固满足工程自身稳定性需求,同时兼顾对周边生态环境,提出了一种新型海塘改造形式——混凝土框架结构。结合浙江东部健跳塘提升改造工程,分析了结构作用机理,对工程稳定性进行了计算,并结合塘身沉降监测数据对混凝土框架结构的实际应用情况进行了研究。结果表明:混凝土框架结构稳定性及桩基受力满足要求,适用于软土环境工程;该结构形式安全稳定,能够减小工程建设对周边生态环境的影响。该结构改造形式可为海塘工程提供参考。 展开更多
关键词 海塘加固 混凝土框架结构 淤泥质土 稳定性计算 桩身受力
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应对可转移多黏菌素耐药性--饲料添加剂来源的白屈菜红碱具有双重效应
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作者 Huangwei Song Xueyang wang +12 位作者 Muchen Zhang Zhiyu Zou Siyuan yang Tian Yi Jianfeng wang Dejun Liu Yingbo Shen Chongshan Dai Zhihai Liu Timothy R.Walsh Jianzhong Shen Congming Wu yang wang 《Engineering》 SCIE EI CAS CSCD 2024年第1期163-173,共11页
The emergence and spread of the mobile colistin-resistance gene,mcr-1,and its variants pose achallenge to the use of colistin,a last-resort antibiotic used to treat severe infections caused by extensively drug-resista... The emergence and spread of the mobile colistin-resistance gene,mcr-1,and its variants pose achallenge to the use of colistin,a last-resort antibiotic used to treat severe infections caused by extensively drug-resistant(XDR)Gram-negative pathogens.Antibiotic adjuvants are a promising strategy to enhance the efficacy of colistin against colistin-resistant pathogens;however,few studies have considered the effects of adjuvants on limiting resistance-gene transmission.We found that chelerythrine(4 mg·L^(-1))derived from Macleaya cordata extract,which is used as an animal feed additive,reduced the minimal inhibitory concentration(MIC)of colistin against an mcr-1 positive Escherichia coli(E.coli)strain by 16-fold(from 2.000 to 0.125 mg·L^(-1)).eliminated approximately 10^(4) colony-forming units(CFUs)of an mcr-1-carrying strain in a murine intestinal infection model,and inhibited the conjugation of an mcr-1-bearing plasmid in vitro(by>100-fold)and in a mouse model(by up to 5-fold).A detailed analysis revealed that chelery-thrine binds to phospholipids on bacterial membranes and increases cytoplasmic membrane fluidity,thereby impairing respiration,disrupting proton motive force(PMF),generating reactive oxygen species(ROS),and decreasing intracellular adenosine triphosphate(ATP)levels,which subsequently downregu-lates mcr-1 and conjugation-associated genes.These dual effects of chelerythrine can expand the use of antibiotic adjuvants and may provide a new strategy for circumventing mobile colistin resistance. 展开更多
关键词 CHELERYTHRINE Antibiotic adjuvant Conjugation inhibitor COLISTIN mcr-1 Dual effects
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Soil properties and not plant factors affect both abundant and rare microbial taxa after thinning in a mixed stand of Cunninghamia lanceolata and Sassafras tzumu
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作者 Wanxia Peng Tongqing Song +5 位作者 Hu Du Feng wang Fuping Zeng yang wang Shulin Chen Yinzhu Chen 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期81-94,共14页
Thinning is an effective management step for sustainable forest development,yet less attention is paid to the restoration of soil microbiota after thinning.In this study,both abundant and rare soil microbial communiti... Thinning is an effective management step for sustainable forest development,yet less attention is paid to the restoration of soil microbiota after thinning.In this study,both abundant and rare soil microbial communities(i.e.,bacterial,fungal),were evaluated under various thinning treatments in a mixed stand of Cunninghamia lanceolata and Sassafras tzumu using Mi Seq sequencing.Thinning did not significantly change either abundant or rare bacterial and fungal community composition,but affected their alpha diversity.The Shannon–Wiener indexes of rare fungal taxa under medium thinning were significantly lower than in the light thinning(P<0.05 level).Xanthobacteraceae dominated the abundant bacterial taxa,and Saitozyma and Mortierlla the abundant fungal taxa.The most common rare bacterial taxa varied;there was no prevalent rare fungal taxa under different thinnings.In addition,soil available nitrogen,total phosphorus,and p H had significant effects on rare bacterial taxa.Nutrients,especially available phosphorus,but not nitrogen,affected abundant and rare soil fungi.The results indicate that soil properties rather than plant factors affect abundant and rare microbial communities in soils of mixed stands.Thinning,through mediating soil properties,influences both abundant and rare bacterial and fungal communities in the mixed C.lanceolata and S.tzumu stand. 展开更多
关键词 Diversity Abundant taxa Rare taxa THINNING Mixed stand
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Pressure transient characteristics of non-uniform conductivity fractured wells in viscoelasticity polymer flooding based on oil-water two-phase flow
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作者 yang wang Jia Zhang +2 位作者 Shi-Long yang Ze-Xuan Xu Shi-Qing Cheng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期343-351,共9页
Polymer flooding in fractured wells has been extensively applied in oilfields to enhance oil recovery.In contrast to water,polymer solution exhibits non-Newtonian and nonlinear behavior such as effects of shear thinni... Polymer flooding in fractured wells has been extensively applied in oilfields to enhance oil recovery.In contrast to water,polymer solution exhibits non-Newtonian and nonlinear behavior such as effects of shear thinning and shear thickening,polymer convection,diffusion,adsorption retention,inaccessible pore volume and reduced effective permeability.Meanwhile,the flux density and fracture conductivity along the hydraulic fracture are generally non-uniform due to the effects of pressure distribution,formation damage,and proppant breakage.In this paper,we present an oil-water two-phase flow model that captures these complex non-Newtonian and nonlinear behavior,and non-uniform fracture characteristics in fractured polymer flooding.The hydraulic fracture is firstly divided into two parts:high-conductivity fracture near the wellbore and low-conductivity fracture in the far-wellbore section.A hybrid grid system,including perpendicular bisection(PEBI)and Cartesian grid,is applied to discrete the partial differential flow equations,and the local grid refinement method is applied in the near-wellbore region to accurately calculate the pressure distribution and shear rate of polymer solution.The combination of polymer behavior characterizations and numerical flow simulations are applied,resulting in the calculation for the distribution of water saturation,polymer concentration and reservoir pressure.Compared with the polymer flooding well with uniform fracture conductivity,this non-uniform fracture conductivity model exhibits the larger pressure difference,and the shorter bilinear flow period due to the decrease of fracture flow ability in the far-wellbore section.The field case of the fall-off test demonstrates that the proposed method characterizes fracture characteristics more accurately,and yields fracture half-lengths that better match engineering reality,enabling a quantitative segmented characterization of the near-wellbore section with high fracture conductivity and the far-wellbore section with low fracture conductivity.The novelty of this paper is the analysis of pressure performances caused by the fracture dynamics and polymer rheology,as well as an analysis method that derives formation and fracture parameters based on the pressure and its derivative curves. 展开更多
关键词 Polymer flooding Non-Newtonian fluid Non-uniform fracture conductivity Two-phase flow Pressure transient analysis
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基于R2AU-Net的InSAR相位解缠方法
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作者 何毅 杨旺 朱庆 《测绘学报》 EI CSCD 北大核心 2024年第3期435-449,共15页
InSAR相位解缠的质量直接影响地形高程或地表形变的反演精度。传统的基于非机器学习模型的相位解缠方法(如基于路径跟踪或最小范数)在低相干性或相位梯度较大(干涉条纹密集)的区域难以获得正确解缠结果。深度神经网络算法在非线性表示... InSAR相位解缠的质量直接影响地形高程或地表形变的反演精度。传统的基于非机器学习模型的相位解缠方法(如基于路径跟踪或最小范数)在低相干性或相位梯度较大(干涉条纹密集)的区域难以获得正确解缠结果。深度神经网络算法在非线性表示和特征表达能力方面具有独特优势,被广泛应用于数字图像处理研究中,InSAR相位解缠可视为图像回归。本文提出基于R2AU-Net深度神经网络的InSAR相位解缠方法。首先,基于数学分形法模拟成对的缠绕和解缠相位,避免了外部DEM合成相位时引入的固有误差和残缺问题,保持了地貌特征的多样性及复杂性,得到模型训练所需的数据集。然后,基于传统的U-Net模型构建R2AU-Net相位解缠模型,该模型结合注意力机制增强了模型对于卷积特征筛选能力,提高了在低相干或条纹密集区域的解缠性能;使用循环残差卷积结构,避免了梯度消失问题,增强了模型特征表示能力。最后,利用模拟和真实数据进行试验分析,结果表明本文提出的R2AU-Net相位解缠模型能够更有效地保留地形高程或真实地表形变信息,提高了解缠结果的可靠性,在性能表现上优于Goldstein枝切法、SNAPHU方法及CNN和U-Net相位解缠模型。 展开更多
关键词 INSAR 相位解缠 深度神经网络 U-Net 地表形变
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Heat exposure and hospitalizations for chronic kidney disease in China: a nationwide time series study in 261 major Chinese cities
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作者 Fu-Lin wang Wan-Zhou wang +9 位作者 Fei-Fei Zhang Su-Yuan Peng Huai-Yu wang Rui Chen Jin-Wei wang Peng-Fei Li yang wang Ming-Hui Zhao Chao yang Lu-Xia Zhang 《Military Medical Research》 SCIE CAS CSCD 2024年第4期469-478,共10页
Background:Climate change profoundly shapes the population health at the global scale.However,there was still insufficient and inconsistent evidence for the association between heat exposure and chronic kidney disease... Background:Climate change profoundly shapes the population health at the global scale.However,there was still insufficient and inconsistent evidence for the association between heat exposure and chronic kidney disease(CKD).Methods:In the present study,we studied the association of heat exposure with hospitalizations for cause-specific CKD using a national inpatient database in China during the study period of hot season from 2015 to 2018.Standard time-series regression models and random-effects Meta-analysis were developed to estimate the city-specific and national averaged associations at a 7 lag-day span,respectively.Results:A total of 768,129 hospitalizations for CKD was recorded during the study period.The results showed that higher temperature was associated with elevated risk of hospitalizations for CKD,especially in sub-tropical cities.With a 1℃ increase in daily mean temperature,the cumulative relative risks(RR)over lag 0-7 d were 1.008[95% confidence interval(CI)1.003-1.012]for nationwide.The attributable fraction of CKD hospitalizations due to high temperatures was 5.50%.Stronger associations were observed among younger patients and those with obstructive nephropathy.Our study also found that exposure to heatwaves was associated with added risk of hospitalizations for CKD compared to non-heatwave days(RR=1.116,95%CI 1.069-1.166)above the effect of daily mean temperature.Conclusions:Short-term heat exposure may increase the risk of hospitalization for CKD.Our findings provide insights into the health effects of climate change and suggest the necessity of guided protection strategies against the adverse effects of high temperatures. 展开更多
关键词 Chronic kidney disease HOSPITALIZATION Climate change Temperature Time-series study
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Topology optimization of chiral metamaterials with application to underwater sound insulation
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作者 Chao wang Honggang ZHAO +3 位作者 yang wang Jie ZHONG Dianlong YU Jihong WEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第7期1119-1138,共20页
Chiral metamaterials have been proven to possess many appealing mechanical phenomena,such as negative Poisson's ratio,high-impact resistance,and energy absorption.This work extends the applications of chiral metam... Chiral metamaterials have been proven to possess many appealing mechanical phenomena,such as negative Poisson's ratio,high-impact resistance,and energy absorption.This work extends the applications of chiral metamaterials to underwater sound insulation.Various chiral metamaterials with low acoustic impedance and proper stiffness are inversely designed using the topology optimization scheme.Low acoustic impedance enables the metamaterials to have a high and broadband sound transmission loss(STL),while proper stiffness guarantees its robust acoustic performance under a hydrostatic pressure.As proof-of-concept demonstrations,two specimens are fabricated and tested in a water-filled impedance tube.Experimental results show that,on average,over 95%incident sound energy can be isolated by the specimens in a broad frequency range from 1 k Hz to 5 k Hz,while the sound insulation performance keeps stable under a certain hydrostatic pressure.This work may provide new insights for chiral metamaterials into the underwater applications with sound insulation. 展开更多
关键词 chiral metamaterial topology optimization underwater sound insulation low acoustic impedance sound transmission loss(STL)
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