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DD494合金叶片返回料的热处理

金属热处理 2024年第6期49卷 1-7页

作者：杨姗洁郝志博袁晓飞北京钢研高纳科技股份有限公司北京100081

研究了3种热处理工艺对DD494合金叶片返回料组织、持久性能及断裂模式的影响。通过金相观察法确定合金的初熔温度,采用扫描电镜(SEM)分析了不同固溶处理温度对合金γ/γ′共晶溶解程度及γ′相形貌的影响,以及不同一级时效处理温度对γ... 详细信息

研究了3种热处理工艺对DD494合金叶片返回料组织、持久性能及断裂模式的影响。通过金相观察法确定合金的初熔温度,采用扫描电镜(SEM)分析了不同固溶处理温度对合金γ/γ′共晶溶解程度及γ′相形貌的影响,以及不同一级时效处理温度对γ′相尺寸及分布的影响。结果表明,合金的初熔温度在1310~1315℃之间。经1300℃×4 h固溶处理并空冷后,合金中γ/γ′共晶数量较1290℃×4 h固溶处理后有所降低,且γ′相更为细小。较单步固溶处理而言,分段固溶处理工艺能降低合金中的共晶含量。一级时效处理温度由1080℃升高到1140℃,析出的γ′相有所长大,同时在γ基体中观察到大量细小二次γ′相。合金的最佳热处理工艺为分段固溶+高温一级时效+二级时效,即1280℃×1 h+1290℃×2 h+1300℃×6 h,AC+1140℃×3 h,AC+870℃×20 h,AC,该工艺下的合金平均持久寿命达到175.05 h,较经单步固溶+低温一级时效+二级时效处理的试样平均持久寿命提高一倍以上。

关键词： DD494合金叶片返回料热处理 γ′析出相持久断裂机制

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青少年心境障碍患者自杀未遂的影响因素分析

首都医科大学学报 2024年第1期45卷 81-87页

作者：袁晓菲刘梦琪吴元贞田音任艳萍陈旭首都医科大学附属北京安定医院国家精神疾病医学中心国家精神心理疾病临床医学研究中心精神疾病诊断与治疗北京市重点实验室北京100088 人脑保护高精尖创新中心首都医科大学北京100069

目的探讨青少年心境障碍(mood disorder,MD)患者伴有自杀未遂(suicide attempt,SA)的影响因素。方法采取横断面调查方式,招募2022年8月3日至2023年9月25日在首都医科大学附属北京安定医院儿童青少年病房住院的105例青少年MD患者纳入研究... 详细信息

目的探讨青少年心境障碍(mood disorder,MD)患者伴有自杀未遂(suicide attempt,SA)的影响因素。方法采取横断面调查方式,招募2022年8月3日至2023年9月25日在首都医科大学附属北京安定医院儿童青少年病房住院的105例青少年MD患者纳入研究,并根据是否存在SA,分为SA组(n=41)和非SA组(n=64)。收集患者的一般人口学资料,采用抑郁症筛查量表(Patient Health Questionnare 9-item Scale,PHQ-9)、广泛性焦虑问卷(Generalized Anxiety Disorder 7-item Scale,GAD-7)、儿童期创伤问卷(Childhood Trauma Questinnaire,CTQ)、Barratt冲动性量表(Barratt Impulsiveness Scale,BIS-11)中文版进行临床症状评估,并采用χ2/t检验对上述因素进行差异性分析,随后对差异有统计学意义的因素采用多因素Logistic回归对SA的相关因素进行分析。结果SA的发生率为39%(41/105),其中女性为42.5%(37/87),男性为22.2%(4/18)。单因素分析结果显示,女性、母亲受教育程度低更容易出现SA(P均<0.05),SA组患者在PHQ-9总分、GAD-7总分、情感忽视及躯体忽视的比例均高于非SA组(P均<0.05)。Logistic回归分析显示,焦虑(OR=1.246,95%CI:1.048~1.480,P=0.013)、母亲受教育程度低(OR=1.522,95%CI:1.040~2.229,P=0.031)是青少年MD患者伴有SA的危险因素。结论青少年MD患者SA发生率较高,伴有焦虑症状和母亲受教育程度低是发生SA的危险因素。

关键词：青少年心境障碍自杀未遂焦虑症状母亲受教育程度

A critical review of on-site inorganic arsenic screening methods

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Journal of Environmental Sciences 2023年第3期125卷 453-469页

作者： Yi He Jingyu Liu Yanhua Duan xiaofei yuan Lulu Ma Ratan Dhar Yan Zheng Department of Sciences John Jay College and the Graduate CenterThe City University of New YorkNY 10019USA State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control School of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control School of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China Queensland Alliance for Environmental Health Sciences(QAEHS) The University of QueenslandQLD 4102Australia Department of Earth and Physical Sciences York CollegeThe City University of New YorkNY 11451USA

Approximately 94 to 220 million people worldwide are at risk of drinking well water containing arsenic > 10 μg/L, the WHO guideline value. To identify non-compliant domestic wells, assess health risks and reduce exposure, accurate and rapid on-site inorganic arsenic screening methods are desirable because all domestic wells worldwide need to be ***, the principles, advantages and limitations of commonly used colorimetry, electrochemistry, and biosensing methods are critically reviewed, with the performance compared with laboratory-based benchmark methods. Most commercial kits are based on the classic Gutzeit reaction. Despite being semi-quantitative, the more recent and more expensive products display improved and acceptable accuracy and shorter testing time (~10 min). Carried out by trained professionals, electrochemical methods are also feasible for on-site analysis, although miniaturization is desirable yet challenging. Biosensing using whole bacterial cells or bio-engineered materials such as aptamers is promising, if incorporated with function specific nanomaterials and biomaterials. Since arsenic is frequently found as arsenite in reducing groundwater and subject to oxidation during sampling, transportation and storage, on-site separation and sample preservation are feasible but the specific methods should be chosen based on sample matrix and tested before use. To eliminate arsenic exposure among hundreds of millions of mostly rural residents worldwide, we call for concerted efforts in research community and regulatory authority to develop accurate, rapid, and affordable tests for on-site screening and monitoring of arsenic in drinking water. Access to affordable testing will benefit people who are socioeconomically disadvantaged.

关键词： Inorganic arsenic On-site analysis Drinking water Groundwater Field test

A modified θ projection model for constant load creep curves-Ⅱ.Application of creep life prediction

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Journal of Materials Science & Technology 2019年第4期35卷 687-694页

作者： Chao Fu Yadong Chen xiaofei yuan Sammy Tin Stoichko Antonov Koichi Yagi Qiang Feng Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology Beijing Department of Mechanical Materials& Aerospace EngineeringIllinois Institute of Technology National Center for Materials Service Safety University of Science and Technology Beijing

To minimize the deviation of the predicted creep curves obtained under constant load conditions by the original θ projection model, a new modified version that can be expressed by ε = θ_1(1-e^(-θ2t)) +θ3 (e^(θ_4e^θ5^εt)-1), was derived and experimentally validated in our last study. In the present study, the predictive capability of the modified θ projection model was investigated by comparing the simulated and experimentally determined creep curves of K465 and DZ125 superalloys over a range of temperatures and stresses. Furthermore, the linear relationship between creep temperature and initial stress was extended to the 5-parameter model. The results indicated that the modified model could be used as a creep life prediction method, as it described the creep curve shape and resulted in predictions that fall within a specified error interval. Meanwhile, this modified model provides a more accurate way of describing creep curves under constant load conditions. The limitations and future direction of the modified model were also discussed. In addition, this modified θ projection model shows great potential for the evaluation and assessment of the service safety of structural materials used in components governed by creep deformation.

关键词： Superalloy Constant load creep Modified θ projection model Uniform deformation stage Prediction performance

A modified θ projection model for constant load creep *** of the model

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Journal of Materials Science & Technology 2019年第1期35卷 223-230页

作者： Chao Fu Yadong Chen xiaofei yuan Sammy Tin Stoichko Antonov Koichi Yagi Qiang Feng Beijing Advanced Innovation Center for Material Genome Engineering State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Department of Mechanical Materials & Aerospace Engineering Illinois Institute of Technology National Center for Materials Service Safety University of Science and Technology Beijing

Estimating long-term creep deformation and life of materials is an effective way to ensure the service safety and to reduce the cost of long-term integrity evaluation of high temperature structural *** the 1980 s, the θ projection model has been widely used for predicting creep lives due to its ability to capture the characteristic transitions observed in creep curves obtained under constant true stress conditions. However, the creep rupture behavior under constant load or engineering stress conditions cannot be simulated accurately using this model because of the different stress states. In this paper, creep curves obtained under constant load conditions were analyzed using a modified θ projection model by considering the increase in true stress with creep deformation during the creep tests. This model is expressed as ε = θ_1(1-e^(-θ_2t)) + θ3 e^(θ_4e^θ5^εt)-1, and was validated using the creep curves of K465 and DZ125 superalloys tested at a range of temperatures and engineering stresses. Moreover, it was shown that the predictive capability of the modified θ projection model was significantly improved over the original one, as it reduces the prediction uncertainty from a range of 10% to 20% to below 5%. Meanwhile,it was shown that the model can be reasonably used for predicting constant stress creep conditions, when appropriate parameters are used. The prediction performance of the modified model will be discussed in another paper. The results of this study show great potential for the evaluation and assessment of the service safety of structural materials used in applications where designs are limited by creep deformation.

关键词： Superalloy Creep Life prediction Modified θ projection model Constant load creep

归脾汤联合琥珀酸亚铁片和输血治疗用于重度缺铁性贫血患者的疗效及对血常规指标、铁代谢和免疫功能的影响

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中国医院用药评价与分析 2024年第4期24卷 439-442页

作者：陈哲崔冬梅张灵袁小飞张斌高炳华河北北方学院附属第一医院血液科河北张家口075061 北京市平谷区医院血液科北京101200 河北北方学院附属第一医院检验科河北张家口075061

目的:探讨归脾汤联合琥珀酸亚铁片和输血治疗用于重度缺铁性贫血患者的疗效及对血常规指标、铁代谢和免疫功能的影响。方法:选取2018年1月至2023年5月于河北北方学院附属第一医院就诊的重度缺铁性贫血患者130例,以信封抽签法随机分为观... 详细信息

目的:探讨归脾汤联合琥珀酸亚铁片和输血治疗用于重度缺铁性贫血患者的疗效及对血常规指标、铁代谢和免疫功能的影响。方法:选取2018年1月至2023年5月于河北北方学院附属第一医院就诊的重度缺铁性贫血患者130例,以信封抽签法随机分为观察组(65例)和对照组(65例)。两组患者均给予输血治疗,对照组患者口服琥珀酸亚铁片,观察组患者口服琥珀酸亚铁片和归脾汤。治疗4周后,对临床疗效进行评价,观察治疗前后两组患者的血常规指标[血红蛋白(Hb)、红细胞计数(RBC)、平均红细胞血红蛋白量(MCH)和平均红细胞体积(MCV)]、铁代谢指标[血清铁(SI)、血清铁蛋白(SF)和可溶性转铁蛋白受体(sTfR)]及免疫功能指标(CD3^(+)、CD4^(+)和CD8^(+)T淋巴细胞比例)水平,并记录不良反应。结果:与对照组[86.15%(56/65)]比较,观察组患者的总有效率[96.92%(63/65)]更高,差异有统计学意义(P0.05)。结论:归脾汤联合琥珀酸亚铁片和输血治疗用于重度缺铁性贫血患者的疗效较好,可改善血常规指标、铁代谢情况及免疫功能,且安全性好。

关键词：归脾汤琥珀酸亚铁片输血治疗重度缺铁性贫血

双相情感障碍抑郁发作患者出院后1年内再入院的影响因素

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中国民康医学 2024年第14期36卷 1-3页

作者：赵昕王雪袁晓菲王巍巍徐劲节吴涵姜玮首都医科大学附属北京安定医院国家精神疾病医学中心国家精神心理疾病临床医学研究中心精神疾病诊断与治疗北京市重点实验室北京100088 首都医科大学人脑保护高精尖创新中心北京100069

目的:分析双相情感障碍抑郁发作患者出院后1年内再入院的影响因素。方法:选取2018—2022年首都医科大学附属北京安定医院收治的1924例双相情感障碍抑郁发作患者进行横断面研究。收集患者临床资料,统计出院后1年内再入院情况,根据患者是... 详细信息

目的:分析双相情感障碍抑郁发作患者出院后1年内再入院的影响因素。方法:选取2018—2022年首都医科大学附属北京安定医院收治的1924例双相情感障碍抑郁发作患者进行横断面研究。收集患者临床资料,统计出院后1年内再入院情况,根据患者是否再入院将其分为再入院组和未再入院组。采用COX多元回归分析双相情感障碍抑郁发作患者出院后1年内再入院的影响因素。结果:1924例双相情感障碍抑郁发作患者出院后1年内再入院347例,再入院率为18.04%(347/1924);两组性别、文化程度、婚姻状况、精神疾病家族史、使用抗抑郁药物治疗情况比较,差异均无统计学意义(P>0.05);两组年龄、既往住院次数、病程、伴精神病性症状、心境稳定剂应用方式比较,差异均有统计学意义(P<0.05);COX多元回归分析结果显示,年龄较大、既往住院次数多、伴精神病性症状、单用一种心境稳定剂均为双相情感障碍抑郁发作患者出院后1年内再入院的危险因素(P<0.05)。结论:年龄较大、既往住院次数多、伴精神病性症状、单用一种心境稳定剂均为双相情感障碍抑郁发作患者出院后1年内再入院的危险因素。

关键词：双相情感障碍抑郁发作再入院影响因素

A Self-Healing Optoacoustic Patch with High Damage Threshold and Conversion Efficiency for Biomedical Applications

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Nano-Micro Letters 2024年第7期16卷 31-45页

作者： Tao Zhang Cheng-Hui Li Wenbo Li Zhen Wang Zhongya Gu Jiapu Li Junru yuan Jun Ou-Yang xiaofei Yang Benpeng Zhu School of Integrated Circuit Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhan 430074People’s Republic of China State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced MicrostructuresSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093People’s Republic of China National Institute of Dental and Craniofacial Research(NIDCR) National Institutes of Health(NIH)35A Convent DriveBethesdaMD 20892USA Department of Neurology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030People’s Republic of China

Compared with traditional piezoelectric ultrasonic devices,optoacoustic devices have unique advantages such as a simple preparation process,anti-electromagnetic interference,and wireless long-distance power ***,current optoacoustic devices remain limited due to a low damage threshold and energy conversion efficiency,which seriously hinder their widespread *** this study,using a self-healing polydimethylsiloxane(PDMS,Fe-Hpdca-PDMS)and carbon nanotube composite,a flexible optoacoustic patch is developed,which possesses the self-healing capability at room temperature,and can even recover from damage induced by cutting or laser ***,this patch can generate high-intensity ultrasound(>25 MPa)without the focusing *** laser damage threshold is greater than 183.44 mJ cm^(-2),and the optoacoustic energy conversion efficiency reaches a major achievement at 10.66×10^(-3),compared with other carbon-based nanomaterials and PDMS *** patch is also been successfully examined in the application of acoustic flow,thrombolysis,and wireless energy *** findings in this study provides new insight into designing and fabricating of novel ultrasound devices for biomedical applications.

关键词： Optoacoustic Self-healing PDMS Acoustic flow Thrombolytic Wireless energy harvesting

一种有效的适合F-J方法从背景噪声资料中提取多阶频散曲线的台阵划分方法

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地球物理学报 2024年第2期67卷 492-502页

作者：袁艺陈晓非北京大学地球与空间科学学院北京100871 中国地震局第二监测中心西安710054 广东省地球物理高精度成像技术重点实验室(南方科技大学) 深圳518055 南方科技大学地球与空间科学系深圳518055

近年发展起来的从地震背景噪声提取多阶频散曲线的F-J方法是一种台阵分析方法,对某一特定的研究区域内台阵的划分方式直接影响成像的效果.当研究区域地下结构较简单,且台站间距比较均匀时,可以使用简单的平移式移动阵列法;然而若研究区... 详细信息

近年发展起来的从地震背景噪声提取多阶频散曲线的F-J方法是一种台阵分析方法,对某一特定的研究区域内台阵的划分方式直接影响成像的效果.当研究区域地下结构较简单,且台站间距比较均匀时,可以使用简单的平移式移动阵列法;然而若研究区域地下结构复杂多变,尤其是台站间距疏密不均时,就需要根据具体的地域特征灵活划分台阵.本文介绍了一种适用于地下结构复杂及台站间距不均匀区域的台阵划分方法,具有一定的普适性.我们将其应用于美国阿拉斯加及加拿大西北部,验证了相比于简单的沿经纬度移动阵列,我们的分区方法确实大大提高了结果的分辨率,为后续反演研究区域三维速度结构提供了坚实的保障.

关键词： F-J变换台阵划分方法多阶面波阿拉斯加