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沥青路面降温技术研究进展与展望 被引量:3
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作者 金娇 皮培屹 +3 位作者 刘培 高玉超 张扮 LIU Pengfei 《北京工业大学学报》 北大核心 2025年第6期736-755,共20页
沥青路面高温会带来车辙等病害,并增加城市热岛效应,这对路面的使用质量、使用寿命和人类的生活环境产生不利影响,所以急需开发行之有效的沥青路面降温技术,以减少车辙等病害和缓解城市热岛效应。现有的沥青路面降温技术分为被动降温技... 沥青路面高温会带来车辙等病害,并增加城市热岛效应,这对路面的使用质量、使用寿命和人类的生活环境产生不利影响,所以急需开发行之有效的沥青路面降温技术,以减少车辙等病害和缓解城市热岛效应。现有的沥青路面降温技术分为被动降温技术和主动降温技术,而主动降温技术能够更为有效地降低沥青路面温度,且具有智能性、自发性等特点。主动降温技术对应的降温沥青路面主要有热反射路面、相变调温路面、热阻路面、透水路面、能量收集路面、高导热路面。针对上述沥青路面主动降温技术,总结了沥青路面主动降温技术的原理特点、应用方式、运用于沥青路面的实际降温及路用效果,以及降温技术的新方法、新思路,探讨了沥青路面主动降温技术的缺陷和局限性,并对未来沥青路面降温技术发展趋势进行展望。 展开更多
关键词 沥青路面 降温技术 热反射 热传导 能量收集 能量转换
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岩石非线性黏弹塑性损伤蠕变模型研究 被引量:1
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作者 陈有亮 肖鹏 +2 位作者 杜曦 王苏然 RAFIG A 《应用力学学报》 北大核心 2025年第1期133-140,共8页
准确描述岩石蠕变行为的各阶段特征对岩石力学与岩体工程的研究具有重要的意义。由于经典元件组合模型不能较好地描述岩石蠕变过程中的非线性特征,基于损伤力学理论及Kachanov蠕变损伤演化规律,通过改进传统的Kelvin模型和村山体模型,... 准确描述岩石蠕变行为的各阶段特征对岩石力学与岩体工程的研究具有重要的意义。由于经典元件组合模型不能较好地描述岩石蠕变过程中的非线性特征,基于损伤力学理论及Kachanov蠕变损伤演化规律,通过改进传统的Kelvin模型和村山体模型,建立起能够描述岩石衰减蠕变阶段和加速蠕变阶段的非线性函数。将弹性体、线性Kelvin体、非线性Kelvin体、损伤黏弹塑性体进行串联,建立能够同时描述岩石瞬时弹性应变、非线性黏弹性应变、非线性黏塑性应变和黏性应变的非线性黏弹塑性损伤蠕变模型,采用Origin软件的Levenberg-Marquardt算法对模型参数进行了辨识,最后通过用不同应力水平下的砂岩单以及三轴压缩蠕变试验,验证该模型的合理性。结果表明:试验曲线和理论曲线的吻合度较高,所建模型不仅能够准确地描述岩石的瞬时弹性应变阶段、等速蠕变阶段的蠕变曲线特征,而且能够较好地描述衰减蠕变阶段和加速蠕变阶段蠕变曲线的非线性特征,验证了该模型的合理性与准确性。 展开更多
关键词 岩石力学 损伤 非线性 加速蠕变 黏弹塑性蠕变模型
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设计赋能乡村六次产业:基本路径、演化过程及创新实践 被引量:1
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作者 张犁 李思佳 《西北农林科技大学学报(社会科学版)》 北大核心 2025年第1期53-59,共7页
六次产业化是乡村产业发展的必然趋势,是推动乡村高质量发展的重要路径和有效抓手。从分析六次产业化的内涵入手,探寻设计赋能乡村六次产业的基本逻辑和演化机制;从“设计乡村化和乡村设计化”双路径赋能机制和“设计介入-产业协同-融... 六次产业化是乡村产业发展的必然趋势,是推动乡村高质量发展的重要路径和有效抓手。从分析六次产业化的内涵入手,探寻设计赋能乡村六次产业的基本逻辑和演化机制;从“设计乡村化和乡村设计化”双路径赋能机制和“设计介入-产业协同-融合共生”三个赋能维度,探索设计赋能的运行方式;构建一个包含资源支撑、设计驱动、制度保障的理论框架,提出乡村设计实践可以通过“一个框架、一个体系和一套制度”来实现设计赋能,并以农产品包装设计和非遗信息图形设计为案例进行实证分析。指出设计驱动产业融合创新,可促进乡村“三产融合、两化融合、全域融合”,赋能优质资源不断转化为乡村永续发展动能,促进乡村六次产业发展,更好地服务于乡村产业兴旺和高质量发展。 展开更多
关键词 第六产业 设计赋能 产业融合 创新生态
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管网压力对火排燃烧器燃烧及排放特性影响
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作者 李洪涛 宋佳佳 +3 位作者 张佳琦 纪运广 席亚宾 MANFRED Wirsum 《科学技术与工程》 北大核心 2025年第7期2800-2807,共8页
壁挂炉供热是北方农村冬季采暖的主要方式之一。由于供气管网压力波动,壁挂炉易于出现燃烧不稳定现象,甚至发生CO中毒事故。为揭示管网压力变动下燃气壁挂炉内温度场及燃烧产物的变化规律,以火排燃烧器为研究对象,通过数值模拟与实验相... 壁挂炉供热是北方农村冬季采暖的主要方式之一。由于供气管网压力波动,壁挂炉易于出现燃烧不稳定现象,甚至发生CO中毒事故。为揭示管网压力变动下燃气壁挂炉内温度场及燃烧产物的变化规律,以火排燃烧器为研究对象,通过数值模拟与实验相结合的方法研究了单排燃烧器在不同管道压力下引射装置出口处燃气组分的分布、燃烧室内温度、燃烧室出口烟气中CO及NO浓度的变化规律。结果表明:(1)随着燃气入口压力减小,火排出口处甲烷浓度随之上升,甲烷浓度不均匀性增强;(2)随着燃气入口压力减小,燃烧室出口处CO质量浓度逐渐增加,燃气入口压力为500 Pa时,CO质量浓度达到25.2 mg/m^(3),高于人体CO中毒事故限值23 mg/m^(3);燃烧室出口处NO质量浓度呈先增加后减少的趋势,在1500 Pa时达到峰值为18.99 mg/m^(3);(3)随着燃气入口压力减小,燃烧室内最高温度先增加后减小,在500 Pa时温度最低为1840 K,燃烧不充分,燃烧生成的热量少;可见,管网压力变小使壁挂炉燃烧的不稳定性增加且CO浓度也显著变大。本文研究结果可为燃气壁挂炉生产厂家在增强设备安全性方面提供一定的理论支持。 展开更多
关键词 燃烧学 火排燃烧器 压力变动 燃烧特性 烟气组分
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煤变质过程中生物产气特征及微生物代谢机制
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作者 郭红玉 赵树峰 +6 位作者 Norbert Klitzsch 宋晓夏 赵金贵 刘汉斌 王乾 张斌 陈振宏 《天然气工业》 北大核心 2025年第8期181-194,共14页
生物成因煤层气的生成与演化受到多种地质因素的影响,目前对于煤变质过程中生物产气及微生物代谢的影响机制尚缺乏深入研究。为此,选取采自山西省大同市东周窑井田和太原市西山井田马兰矿2个矿区6个不同变质程度的煤样,通过全岩黏土矿... 生物成因煤层气的生成与演化受到多种地质因素的影响,目前对于煤变质过程中生物产气及微生物代谢的影响机制尚缺乏深入研究。为此,选取采自山西省大同市东周窑井田和太原市西山井田马兰矿2个矿区6个不同变质程度的煤样,通过全岩黏土矿物分析、生物产气模拟、主成分分析(PCA)、气相色谱—质谱联用(GC-MS)、宏基因及代谢组学等技术手段,系统研究了煤变质过程中生物产气潜力和影响微生物代谢的机制。研究结果表明:①随着变质程度的增加,煤中总有机碳含量和挥发分含量显著降低,而灰分和黏土矿物含量则增加,黏土矿物类型由高岭土逐渐向伊利石及伊/蒙混层转变;②相应地,两种高变质程度煤样产气量分别降至1.13 mL/g和1.07 mL/g,较低变质程度煤样产气量下降超过50%;③PCA分析结果显示,变质作用通过有机质和矿物组分变化影响生物产气潜力,灰分和黏土矿物含量的增加,限制了有机质的生物可利用性;④尽管高变质程度煤中富集了Petrimonas和Pseudomonas等电活性菌,但由于水解及产酸菌(如Proteobacteria和Synergistota)丰度偏低,甲烷生成仍受到抑制。结论认为:①不同变质程度煤在生物降解过程中具有显著代谢差异,差异代谢物如5-Aminolevulinic acid、Dihydroisophorol和4-Hydroxy-1-(3-pyridinyl)-1-butanone均以酸类代谢为主;②研究成果揭示了煤变质过程对生物产气潜力的多维影响机制,能够为生物成因煤层气资源评价与开发利用提供理论基础与技术支撑。 展开更多
关键词 不同变质程度煤 生物成因煤层气 矿物组成 总有机碳 黏土矿物 液相产物 菌群结构 代谢组学
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基于μCT和深度学习的煤裂隙智能提取方法 被引量:1
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作者 胡咤咤 张寻 +4 位作者 金毅 巩林贤 黄文辉 任建吉 Norbert Klitzsch 《煤田地质与勘探》 北大核心 2025年第2期55-66,共12页
【目的】煤储层裂隙的精细描述对于煤层气资源的勘探开发具有重要意义,裂隙的尺寸、走向、分布密度等直接影响煤层的渗透性,准确识别和提取煤层中的裂隙信息是揭示体积压裂过程中裂缝网络形成与扩展机理的关键。传统的裂隙提取方法往往... 【目的】煤储层裂隙的精细描述对于煤层气资源的勘探开发具有重要意义,裂隙的尺寸、走向、分布密度等直接影响煤层的渗透性,准确识别和提取煤层中的裂隙信息是揭示体积压裂过程中裂缝网络形成与扩展机理的关键。传统的裂隙提取方法往往依赖人工标注和基于一定图像处理技术的特征提取,这些方法在精度和效率上存在明显不足。【方法】提出一种基于Trans-UNet网络和μCT图像的煤裂隙提取方法,Trans-UNet结合了Transformer模块和卷积神经网络(CNN)的优点,不仅具备全局特征提取能力,还能够捕捉图像中的局部细节特征,大幅提高了分割精度和网络的鲁棒性。首先对煤样μCT图像进行预处理,包括使用差值法提高图像质量、使用数据增强技术扩大样本数量等。随后,利用Trans-UNet网络对处理后的图像进行分割,提取裂隙特征,并比较不同神经网络模型的分割结果。【结果和结论】结果表明,提出的方法在数据集上表现出优越性能,Trans-UNet模型在煤裂隙提取上的准确性(accuracy)、精确度(precision)、F1分数(F1-score)和交并比(IoU)分别达到91.3%、89.5%、89.8%和84.0%,相较于U-Net、U-Net++等其他多种智能模型有显著提升。结合μCT图像的细粒度特征,将Trans-UNet网络应用于煤裂隙提取任务,是一种高效且准确的解决方案,为煤层气勘探开发领域的相关图像处理任务提供了新的思路。 展开更多
关键词 Trans-UNet μCT图像 煤裂隙 图像分割 深度学习
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考虑非稳态渗流影响的深埋隧道弹塑性解
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作者 林贤哲 陈有亮 +3 位作者 刘耕云 李溢 拉菲格·阿扎姆 陈奇键 《工业建筑》 2025年第4期132-141,共10页
为研究在非稳态渗流条件下的深埋水工隧道围岩开挖力学响应,基于Mohr-Coulomb强度准则,推导了考虑非稳态渗流和剪胀效应的深埋水工隧洞弹塑性解。采用分离变量法和Bessel函数理论,推导了隧洞开挖引起的非稳态渗流场水头分布解析解。由... 为研究在非稳态渗流条件下的深埋水工隧道围岩开挖力学响应,基于Mohr-Coulomb强度准则,推导了考虑非稳态渗流和剪胀效应的深埋水工隧洞弹塑性解。采用分离变量法和Bessel函数理论,推导了隧洞开挖引起的非稳态渗流场水头分布解析解。由参数敏感性分析得知:与稳态渗流场相比,非稳态渗流场对围岩稳定性具有显著的影响,即塑性区扩大时,松动圈厚度和围岩塑性区变形增大;非稳态渗流对围岩塑性区变形的影响不可忽视,尤其在相同剪胀角条件下,洞壁处径向位移远大于稳态渗流引起的洞壁位移。 展开更多
关键词 深埋隧道 非稳态渗流 剪胀 弹塑性解 应力场 位移场
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Substrate topography as a powerful tool to modify glial cell biology and interactions
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作者 Pascal Achenbach Haktan Altinova Gary A.Brook 《Neural Regeneration Research》 SCIE CAS 2025年第5期1390-1391,共2页
Traumatic injuries to the central nervous system(CNS) result in disruption of the intricate network of axons which connect functionally related neurons that are widely distributed throughout the brain and spinal cord.... Traumatic injuries to the central nervous system(CNS) result in disruption of the intricate network of axons which connect functionally related neurons that are widely distributed throughout the brain and spinal cord.Under normal conditions,maintenance of this complex system is structurally and functionally supported by astrocytes (ACs)and other glial cells,the processes of which form a framework surrounding neuronal cell bodies,dendrites,axons,and synapses. 展开更多
关键词 INJURIES TOPOGRAPHY system
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Sensorless battery expansion estimation using electromechanical coupled models and machine learning 被引量:1
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作者 Xue Cai Caiping Zhang +4 位作者 Jue Chen Zeping Chen Linjing Zhang Dirk Uwe Sauer Weihan Li 《Journal of Energy Chemistry》 2025年第6期142-157,I0004,共17页
Developing sensorless techniques for estimating battery expansion is essential for effective mechanical state monitoring,improving the accuracy of digital twin simulation and abnormality detection.Therefore,this paper... Developing sensorless techniques for estimating battery expansion is essential for effective mechanical state monitoring,improving the accuracy of digital twin simulation and abnormality detection.Therefore,this paper presents a data-driven approach to expansion estimation using electromechanical coupled models with machine learning.The proposed method integrates reduced-order impedance models with data-driven mechanical models,coupling the electrochemical and mechanical states through the state of charge(SOC)and mechanical pressure within a state estimation framework.The coupling relationship was established through experimental insights into pressure-related impedance parameters and the nonlinear mechanical behavior with SOC and pressure.The data-driven model was interpreted by introducing a novel swelling coefficient defined by component stiffnesses to capture the nonlinear mechanical behavior across various mechanical constraints.Sensitivity analysis of the impedance model shows that updating model parameters with pressure can reduce the mean absolute error of simulated voltage by 20 mV and SOC estimation error by 2%.The results demonstrate the model's estimation capabilities,achieving a root mean square error of less than 1 kPa when the maximum expansion force is from 30 kPa to 120 kPa,outperforming calibrated stiffness models and other machine learning techniques.The model's robustness and generalizability are further supported by its effective handling of SOC estimation and pressure measurement errors.This work highlights the importance of the proposed framework in enhancing state estimation and fault diagnosis for lithium-ion batteries. 展开更多
关键词 Sensorless estimation Electromechanical coupling Impedance model Data-driven model Mechanical pressure
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Risks and governance of heavy metals in European soil applied phosphate fertilizers 被引量:1
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作者 Lian-kai Zhang Xiang Liu +5 位作者 Ya-jie Sun Bernd G.Lottermoser Roland Bol Heike Windmann Silvia H.Haneklaus Ewald Schnug 《China Geology》 2025年第3期560-572,共13页
Phosphorus(P)poses a global challenge to the environment and human health due to its natural association with heavy metals.Sustainable use of P is crucial to ensure food security for future generations.An analysis of ... Phosphorus(P)poses a global challenge to the environment and human health due to its natural association with heavy metals.Sustainable use of P is crucial to ensure food security for future generations.An analysis of the 150 phosphate fertilizers stored at the Institute for Crop and Soil Science in Germany has been conducted,supplemented by previously published data.The elements Cd,Bi,U,Cr,Zn,Tl,As,B,Sb,Ni,and Se are found in higher concentrations in sedimentary derived phosphates compared to igneous derived phosphates.Mineral fertilizers contain more than ten times the amount of U,Cd,B,and As compared to farmyard manure.Principal component analyses(PCA)indicate that U,Cd,Be,and Cr are primarily present in sedimentary derived phosphates and their concentrations are 2 to 10 times higher than those in igneous derived phosphates.Regarding heavy metal contamination,over 1000 potential combinations were identified;36% of these were significant but weak(>0.1).It is estimated that approximately 707 t of uranium enter farmland annually through the application of mineral phosphate fertilizers in European countries.This contribution addresses environmental issues related to the utilization of rock phosphate as well as alternative production methods for cleaner and safer phosphate fertilizers while presenting a roadmap with measures for mitigation. 展开更多
关键词 Phosphorus fertilizer Heavy metals U-Cd-Cr-Tl SOIL Mitigation Sustainable measures EUROPE Sustainable Development Goals(SDG 3) Environmental geological survey engineering
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Proton pump inhibitors and all-cause mortality risk among cancer patients
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作者 Arunkumar Krishnan Carolin Victoria Schneider Declan Walsh 《World Journal of Clinical Oncology》 2025年第1期34-42,共9页
BACKGROUND Proton pump inhibitors(PPIs)are widely used,including among cancer patients,to manage gastroesophageal reflux and other gastric acid-related disorders.Recent evidence suggests associations between long-term... BACKGROUND Proton pump inhibitors(PPIs)are widely used,including among cancer patients,to manage gastroesophageal reflux and other gastric acid-related disorders.Recent evidence suggests associations between long-term PPI use and higher risks for various adverse health outcomes,including greater mortality.AIM To investigate the association between PPI use and all-cause mortality among cancer patients by a comprehensive analysis after adjustment for various confounders and a robust methodological approach to minimize bias.METHODS This retrospective cohort study used data from the TriNetX research network,with electronic health records from multiple healthcare organizations.The study employed a new-user,active comparator design,which compared newly treated PPI users with non-users and newly treated histamine2 receptor antagonists(H2RA)users among adult cancer patients.Newly prescribed PPIs(esomeprazole,lansoprazole,omeprazole,pantoprazole,or rabeprazole)users were compared to non-users or newly prescribed H2RAs(cimetidine,famotidine,nizatidine,or ranitidine)users.The primary outcome was all-cause mortality.Each patient in the main group was matched to a patient in the control group using 1:1 propensity score matching to reduce confounding effects.Multivariable Cox regression models were used to estimate hazard ratios(HRs)and 95% confidence interval(CI).RESULTS During the follow-up period(median 5.4±1.8 years for PPI users and 6.5±1.0 years for non-users),PPI users demonstrated a higher all-cause mortality rate than non-users after 1 year,2 years,and at the end of follow up(HRs:2.34-2.72).Compared with H2RA users,PPI users demonstrated a higher rate of all-cause mortality HR:1.51(95%CI:1.41-1.69).Similar results were observed across sensitivity analyses by excluding deaths from the first 9 months and 1-year post-exposure,confirming the robustness of these findings.In a sensitivity analysis,we analyzed all-cause mortality outcomes between former PPI users and individuals who have never used PPIs,providing insights into the long-term effects of past PPI use.In addition,at 1-year follow-up,the analysis revealed a significant difference in mortality rates between former PPI users and non-users(HR:1.84;95%CI:1.82-1.96).CONCLUSION PPI use among cancer patients was associated with a higher risk of all-cause mortality compared to non-users or H2RA users.These findings emphasize the need for cautious use of PPIs in cancer patients and suggest that alternative treatments should be considered when clinically feasible.However,further studies are needed to corroborate our findings,given the significant adverse outcomes in cancer patients. 展开更多
关键词 All-cause mortality CANCER Histamine-2 receptor antagonists MORTALITY MALIGNANCY Proton pump inhibitors CARCINOMA OUTCOME
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A NURBS-based, perfectly matched layer method for transient elastodynamics in unbounded domains
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作者 Arturo Méndez Salas Myung-Jin Choi Sven Klinkel 《Earthquake Engineering and Engineering Vibration》 2025年第3期723-742,共20页
In this study,the wave motion in elastodynamics for unbounded media is modeled using an unsplit-field perfectly matched layer(PML)formulation that is solved by employing an isogeometric analysis(IGA).In the adopted co... In this study,the wave motion in elastodynamics for unbounded media is modeled using an unsplit-field perfectly matched layer(PML)formulation that is solved by employing an isogeometric analysis(IGA).In the adopted combination,the non-uniform rational B-spline(NURBS)functions are employed as basis functions.Moreover,the unbounded and artificial domains,defined in the PML method,are contained in a single patch domain.Based on the proposed scheme,the approximation of the geometry problem is set in a new scheme in which the PML’s absorbing and attenuation properties and the description of traveling waves can be represented.This includes a higher continuity and smoother approximation of the computed domain.As high-order NURBS basis functions are non-interpolatory,a penalty method is present to apply a time-dependent displacement load.The performance of the NURBS-based PML is analyzed through numerical examples for 1D and 2D domains,considering homogeneous and heterogeneous media.Further,we verify the long-time numerical stability of the present method.The developed method can be used to simulate hypothetical stratified domains commonly encountered in soil-structure interaction analyses. 展开更多
关键词 perfectly matched layer NURBS ELASTODYNAMICS unbounded domains transient analysis
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Care for the soul of science:Equity and virtue in reform and reformation
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作者 Mare Knibbe Sarah de Rijcke Bart Penders 《Cultures of Science》 2025年第1期12-23,共12页
Scientific reforms proposed in response to moral concerns about corrupted science are reminiscent of the Christian Reformation,which similarly formed a moral reorientation as a reaction to malpractices.In this study,w... Scientific reforms proposed in response to moral concerns about corrupted science are reminiscent of the Christian Reformation,which similarly formed a moral reorientation as a reaction to malpractices.In this study,we compare these moral reorientation processes to contextualize two different moral programmes of the scientific reform movement and their sociopolitical conditions.We argue that such an explication of moral programmes is vital to build legitimacy and reflect on value-prioritization.While epistemic programmes are foregrounded,moral programmes also play a crucial role in shaping science,and different moral programmes offer different promises for the sustained support of credible,reliable,fair and equitable science.We discuss the virtue and equity programmes,and through interrogating both programmes in relation to the Reformation,we display the relevance of sociopolitical contexts to how key values operate in science and generate orders of worth.These insights aim to stimulate debate about the conditions for opting for either of these moral programmes.In our view,not all moral programmes offer equal promise for the sustained support of credible,equitable and fair science. 展开更多
关键词 Scientific reform REFORMATION moral programme valuation VIRTUE EQUITY
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Understanding pyramidal slip-induced deformation bands and dynamic recrystallization in AZWX3100 magnesium alloy
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作者 Risheng Pei Fatim-Zahra Mouhib +3 位作者 Mattis Seehaus Simon Arnoldi Pei-Ling Sun Talal Al-Samman 《Journal of Magnesium and Alloys》 2025年第3期1088-1098,共11页
Dynamic recrystallization(DRX)in inhomogeneous deformation zones,such as grain boundaries,shear bands,and deformation bands,is critical for texture modification in magnesium alloys during deformation at elevated temper... Dynamic recrystallization(DRX)in inhomogeneous deformation zones,such as grain boundaries,shear bands,and deformation bands,is critical for texture modification in magnesium alloys during deformation at elevated temperatures.This study investigates the DRX mechanisms in AZWX3100 magnesium alloy under plane strain compression at 200℃.Microstructural analysis revealed necklace-type DRX accompanied by evidence of local grain boundary bulging.Additionally,ribbons of recrystallized grains were observed withinfine deformation bands,aligned with theoretical pyramidal I and II slip traces derived from the matrix.The distribution of local misorientation within the deformed microstructure demonstrated a clear association between deformation bands and localized strain.Dislocation analysis of lamellar specimens extracted from two pyramidal slip bands revealed<c+a>dislocations,indicating a connection between<c+a>slip activation and the formation of deformation bands.Crystal plasticity simulations suggest that the orientation of deformation bands is responsible for the unique recrystallization texture of the DRX grains within these bands.The texture characteristics imply a progressive,glide-induced DRX mechanism.A fundamental understanding of the role of deformation bands in texture modification can facilitate future alloy and process design. 展开更多
关键词 Magnesium Channel die Dynamic recrystallization Texture modification Pyramidal slip
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Feasibility of telemedicine in civil protection:a prospective observational study during a music festival
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作者 Anna Müller Robert Arimond +3 位作者 Janosch Kunczik Rolf Rossaint Michael Czaplik Andreas Follmann 《World Journal of Emergency Medicine》 2025年第2期121-128,共8页
BACKGROUND:As disasters intensify and professional deficits persist,civil protection is reliant on medical volunteers.With limited physician availability,telemedicine is promising.No system currently empowers lower-qu... BACKGROUND:As disasters intensify and professional deficits persist,civil protection is reliant on medical volunteers.With limited physician availability,telemedicine is promising.No system currently empowers lower-qualified paramedics for physician-delegated telemedicine.Existing telemedicine technology unfits for civil protection.This study aimed to evaluate a modified system at a music festival to simulate disaster situations.METHODS:A tablet-based telemedicine system,integrating vital sign monitoring,was deployed at the "Summerjam" music festival characterized by various medical emergencies.A physician could be contacted via telemedicine or requested onsite.Medical feasibility was rated by patient condition changes,with National Advisory Committee of Aeronautics(NACA) score and Primary Ranking for Initial Orientation in the Rescue service(PRIOR) algorithm for triaging.Technical feasibility was assessed by connection stability,communication,and vital sign transmission.RESULTS:Of 404 treatments,34(8.4%) were performed using telemedicine,49(12.1%) were carried out with a physician onsite.Telemedicine treatments accounted for 40.9% of all treatment in which a physician was involved.Patient conditions varied up to NACA III(moderate disturbance).A variety of internal medical(76.5%) and surgical(23.5%) conditions were addressed,some of which required invasive measures or application of medication.No patients experienced a deterioration in their condition.Despite technical difficulties,treatment was not significantly impacted,confirming technical feasibility.CONCLUSION:The study shows that lower-qualified paramedics can effectively use telemedicine for physician-delegated treatment,suggesting potential applicability to civil protection.Nonetheless,further system robustness improvements and research are needed. 展开更多
关键词 Disaster medicine Tele-paramedic Civil protection TELEMEDICINE Tele-physician
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Integrating three-dimensional printing and bioprinting technologies to develop a stretchable in vitro model of the human airway
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作者 Junned Chan Julian Gonzalez Rubio +7 位作者 Oscar O’Dwyer Lancaster-Jones Yashasvi Verma Charlotte Büchter Stefan Jockenhoevel Laura De Laporte Mirko Trilling Anja Lena Thiebes Daniela Duarte Campos 《Bio-Design and Manufacturing》 2025年第4期595-608,I0033-I0041,共23页
The global demand for in vitro respiratory airway models has surged due to the coronavirus disease 2019(COVID-19)pandemic.Current state-of-the-art models use polymer membranes to separate epithelial cells from other c... The global demand for in vitro respiratory airway models has surged due to the coronavirus disease 2019(COVID-19)pandemic.Current state-of-the-art models use polymer membranes to separate epithelial cells from other cell types,creating a nonphysiological barrier.In this study,we applied three-dimensional(3D)printing and bioprinting to develop an in vitro model where endothelial and epithelial cells were in direct contact,mimicking their natural arrangement.This proof-ofconcept model includes a culture chamber,with an endothelial bioink printed and perfused through an epithelial channel.In silico simulations of the air velocity within the channel revealed shear stress values ranging from 0.13 to 0.39 Pa,aligning with the desired in vivo shear stress observed in the bronchi regions(0.1–0.4 Pa).Biomechanical movements during resting breathing were mimicked by incorporating a textile mesh positioned away from the cell–cell interface.The epithelial channel demonstrated a capacity for compression and expansion of up to−14.7%and+6.4%,respectively.Microscopic images showed that the epithelial cells formed a uniform monolayer within the lumen of the channel close to the bioprinted endothelial cells.Our novel model offers a valuable tool for future research into respiratory diseases and potential treatments under conditions closely mimicking those in the lung. 展开更多
关键词 Airway-on-a-chip In vitro model BIOPRINTING HYDROGEL Tissue engineering Lung
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Macro and micro mechanical behaviors and micro damage theory of rock at low temperature freeze-thaw cycles
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作者 XIAO Peng CHEN Youliang +1 位作者 FERNÁNDEZ-STEEGER Tomás Manuel RAFIG Azzam 《Journal of Mountain Science》 2025年第6期2227-2240,共14页
Aiming at challenges posed by rock freezethaw(FT)in cold regions rock mass engineering,it is of great significance to analyze its macro-and micromechanical properties and damage laws for the smooth progress of constru... Aiming at challenges posed by rock freezethaw(FT)in cold regions rock mass engineering,it is of great significance to analyze its macro-and micromechanical properties and damage laws for the smooth progress of construction.In this study,indoor freezethaw cycle(FTC)tests on sandstone were conducted to analyze the mass change rate,density change rate,longitudinal wave velocity change rate,microstructure change and mechanical properties of sandstone after FTC.A microscopic FT damage variable reflecting the FT damage was defined based on the changes of rock porosity before and after the FTC,enabling the derivation of the total damage variable under the coupled action of FTC and mechanical loading.A damage evolution equation and a microscopic damage constitutive model for rock under coupled FTC and confining pressure were established by using Lemaitre’s strain equivalence principle,the theory of continuous damage mechanics,and the assumption that the failure of rock micro-units follows the SMP criterion.The rationality and accuracy of the model were verified using triaxial compression test data for FT-damaged rock.The results show that both macroand micro-mechanical properties of sandstone are degraded under the action of FTC,resulting in significant damage.The developed microscopic damage constitutive model can reflect the stress-strain characteristics of the whole process of FT rock triaxial compression,with excellent agreement observed between experimental and theoretical curves.This validates the reliability of the model and the methodology for determining its parameters.Additionally,defining the microscopic FT damage variable based on rock porosity changes is demonstrated to be a feasible and highly accurate approach to reflect rock FT damage degree.This model expands the damage model for rock under the coupling effect of FTC and confining pressure,further illuminating the damage mechanism and failure law in such environments.The findings provide references for the construction of rock mass engineering in cold regions. 展开更多
关键词 Freeze-thaw cycles Mechanical properties Microscopic freeze-thaw damage variable Damage evolution Constitutive model
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Unmet needs in precision psychiatry
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作者 Philipp G Sand Timm B Poeppl Vera Roessler 《World Journal of Psychiatry》 2025年第9期361-364,共4页
A recent meta-analysis has suggested a 5-HTR1A promoter variant may predict antidepressant response.The present review comments on the claims made in view of sensitivity issues and issues pertaining to genetic exposur... A recent meta-analysis has suggested a 5-HTR1A promoter variant may predict antidepressant response.The present review comments on the claims made in view of sensitivity issues and issues pertaining to genetic exposure.We also alert to errors in the original data that had been carried over.Specifically,primers meant to amplify the HTR1A gene aligned to the BDNF gene sequence.Alleles had been confounded owing to DNA strand ambiguities and demographic information proved inaccurate.In the light of these findings,adherence to PRISMA guidelines and use of the Newcastle-Ottawa Scale did not safeguard against bias.More after action reviews are encouraged to identify factors likely to interfere with estimates of genetic risk in large data sets.These may result from pooling of ethnic groups,the use of binary data or other formats that are not human-readable,the introduction of surrogate identifiers and a failure to reverseengineer previously published experimental protocols.Unless the above challenges are met,sequence variants are unlikely to inform personalized medicine strategies in psychiatry. 展开更多
关键词 Major depressive disorder Antidepressant efficacy META-ANALYSIS 5-HTR1A gene C-1019G polymorphism
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Predicting grain boundary segregation in magnesium alloys:An atomistically informed machine learning approach
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作者 Zhuocheng Xie Achraf Atila +3 位作者 Julien Guénolé Sandra Korte-Kerzel Talal Al-Samman Ulrich Kerzel 《Journal of Magnesium and Alloys》 2025年第6期2636-2650,共15页
Grain boundary(GB)segregation substantially influences the mechanical properties and performance of magnesium(Mg).Atomic-scale modeling,typically using ab-initio or semi-empirical approaches,has mainly focused on GB s... Grain boundary(GB)segregation substantially influences the mechanical properties and performance of magnesium(Mg).Atomic-scale modeling,typically using ab-initio or semi-empirical approaches,has mainly focused on GB segregation at highly symmetric GBs in Mg alloys,often failing to capture the diversity of local atomic environments and segregation energies,resulting in inaccurate structure-property predictions.This study employs atomistic simulations and machine learning models to systematically investigate the segregation behavior of common solute elements in polycrystalline Mg at both 0 K and finite temperatures.The machine learning models accurately predict segregation thermodynamics by incorporating energetic and structural descriptors.We found that segregation energy and vibrational free energy follow skew-normal distributions,with hydrostatic stress,an indicator of excess free volume,emerging as an important factor influencing segregation tendency.The local atomic environment's flexibility,quantified by flexibility volume,is also crucial in predicting GB segregation.Comparing the grain boundary solute concentrations calculated via the Langmuir-Mc Lean isotherm with experimental data,we identified a pronounced segregation tendency for Nd,highlighting its potential for GB engineering in Mg alloys.This work demonstrates the powerful synergy of atomistic simulations and machine learning,paving the way for designing advanced lightweight Mg alloys with tailored properties. 展开更多
关键词 Grain boundary segregation Magnesium alloys Atomistic simulation Machine learning.
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Enhanced photocatalytic CO_(2) reduction of Bi_(2)WO_(6)-BiOCl heterostructure with coherent interface for charge utilization
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作者 Hui Li Chunlang Gao +6 位作者 Guo Yang Lu Xia Wulyu Jiang Cheng Wu Kaiwen Wang Yingtang Zhou Xiaodong Han 《Chinese Chemical Letters》 2025年第9期517-523,共7页
The photocatalytic reduction of CO_(2)presents a promising avenue for carbon fuel conversion.However,the efficiency of charge utilization remains a critical barrier to industrial applications.In this study,we introduc... The photocatalytic reduction of CO_(2)presents a promising avenue for carbon fuel conversion.However,the efficiency of charge utilization remains a critical barrier to industrial applications.In this study,we introduce a tandem design of Bi_(2)WO_(6)-BiOCl with an atomically matched interface,achieving highly efficient photoreduction of CO_(2)to CO.By incorporating WO_(4)^(2-)ions and tuning coordination environment,the(110)facet of BiOCl was in-situ grown on the(200)facet of Bi_(2)WO_(6).Compared to single phases and ball-milling samples,Bi_(2)WO_(6)-BiOCl exhibits a remarkable CO yield of 68.03μmol g^(-1)h^(-1)with a selectivity of 98%.Atomic visualization and coordination analysis confirm the formation of a coherent interface that facilitates charge migration for efficient electron transport.Density functional theory(DFT)calculations and in-situ Fourier transform infrared(FTIR)spectroscopy provide insights into the intrinsic active sites and reaction mechanisms.The proposed lattice engineering strategies offer a new paradigm for the rational design of heterostructures beyond traditional band alignment at the atomic scale. 展开更多
关键词 Coherent interface Atomic precision Charge dynamics Photocatalytic CO_(2)reduction HETEROSTRUCTURE
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