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Clinical Significance of Pulmonary Function Tests in Long-Term Survivors after Myeloablative Allogeneic Hematopoietic Stem Cell Transplantation
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作者 Kenji Matsumoto Satomi Ito +4 位作者 Wataru Yamamoto Eriko Ogusa Atsuo Maruta Yoshiaki Ishigatsubo Heiwa Kanamori 《Open Journal of Blood Diseases》 2013年第1期6-12,共7页
We retrospectively assessed long-term pulmonary function in adults surviving for ≥5 years after myeloablative allogeneic hematopoietic stem cell transplantation and identified risk factors for late-onset noninfectiou... We retrospectively assessed long-term pulmonary function in adults surviving for ≥5 years after myeloablative allogeneic hematopoietic stem cell transplantation and identified risk factors for late-onset noninfectious pulmonary complications. Among 174 patients undergoing transplantation for hematologic malignancies between May 1994 and December 2004, 81 long-term survivors were evaluated. Pulmonary function tests (PFTs) were performed before conditioning, 3 months and 1 year after transplantation, and then annually. Eight patients (10%) had abnormal pulmonary function before transplantation, but this was not associated with late changes in PFTs. Patients with chronic graft-versus-host disease (GVHD) showed a significant decline of lung function after 3 years when compared with patients without chronic GVHD. Abnormal pretransplantation lung function was associated with pulmonary chronic GVHD according to National Institutes of Health criteria (score 0, n = 58;score 1, n = 14;score 2, n = 6;score 3, n = 3). Five patients with late-onset noninfectious pulmonary complications showed a decline of lung function at 1 year after transplantation. Only chronic GVHD was significantly related to late-onset noninfectious pulmonary complications. In conclusion, abnormal lung function before transplantation may be associated with a decline in pulmonary function within 1 year after transplantation, but late-onset noninfectious pulmonary complications could not be predicted from pretransplantation lung function. 展开更多
关键词 long-term SURVIVOR PULMONARY Function tests LATE-ONSET Noninfectious PULMONARY COMPLICATIONS MYELOABLATIVE ALLOGENEIC Stem Cell Transplantation
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Translating COVID Tests Terms From Chinese Into English in the Light of Functional Equivalence Theory
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作者 ZHANG Zhengqing JIA Xiaoqing 《Psychology Research》 2022年第9期712-715,共4页
Communication of the various testing methods of COVID-19 is vital for English speakers within China and with the outside world.This research is set to find out the appropriate translation of the Chinese phrases referr... Communication of the various testing methods of COVID-19 is vital for English speakers within China and with the outside world.This research is set to find out the appropriate translation of the Chinese phrases referring to COVID-19 tests in English,in light of functional equivalence theory,which is expected to help correct mistakes and facilitate understanding between people speaking the two languages. 展开更多
关键词 term translation COVID-19 tests functional equivalence theory
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Reflection on the Final-term Intensive Reading Test in a Secondary Vocational School
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作者 沈平 《科技信息》 2009年第3期266-266,307,共2页
This article begins with a brief description of a final-term intensive reading test for students in a secondary vocational school in Shaoxing;then it argues about the test's validity and reliability.Most significa... This article begins with a brief description of a final-term intensive reading test for students in a secondary vocational school in Shaoxing;then it argues about the test's validity and reliability.Most significantly,it discusses the backwash effect of the textbook-based test in students' learning process.Finally,a conclusion is drawn that a final achievement test like this is valid,reliable and applicable to vocational students.Consequently,the textbook-based test is recommended for secondary vocational students(SVS)in their EFL learning. 展开更多
关键词 考试 职业学校 英语 教学方法
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ADPRT-MEDIATED DECREASE OF CELLULAR NAD CONTENT AND THE DETECTION OF CHEMICALLY INDUCED DNA DAMAGE DEVELOPMENT OF A NEW SHORT-TERM SCREENING TEST FOR MUTAGENS
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作者 余应年 戴一凡 +1 位作者 方明 陈星若 《Chinese Medical Sciences Journal》 CAS CSCD 1990年第1期19-24,共6页
It was found that the DNA-damaging agents N-methyl-N’-nitro-N-nitrosoguanidine(MNNG),methyl-methanesulphonate(MMS)and 4-nitroquinoline-N-oxide(4NQO)could stimulate ADP-ribosyl transferase(ADPRT)activity and r... It was found that the DNA-damaging agents N-methyl-N’-nitro-N-nitrosoguanidine(MNNG),methyl-methanesulphonate(MMS)and 4-nitroquinoline-N-oxide(4NQO)could stimulate ADP-ribosyl transferase(ADPRT)activity and reduce the cellular NAD content in a dose-dependent way.The reduction of NAD after DNA damage could be partially or completelyprevented by ADPRT inhibitors,3-aminobenzamide or nicotinamide,which showed noinfluence on reduction of NAD induced by metabolic blocking agents.Therefore,a simpleand specific method to detect DNA-damaging mutagens by measuring ADPRT-mediateddecrease of cellular NAD content was explored.Using β-naphthofiavone,a mixed functionoxygenase inducer,together with induced or uninduced human amnion FL cells,it was foundthat aflatoxin B<sub>1</sub>,benzo(a)pyrene,2-acetylaminofluorene,9,10-dimethylanthracene andethylcarbamate could induce the ADPRT-mediated decrease of cellular NAD content,while4-acetylaminofluorene,anthracene,isopropyl-N-(3-chlorophenyl)-carbamate,β-propiolactone,γ-butyrolactone,cyclophosphamide and safrol could not.The results indicate that this isa cheap and specific method to detect DNA damage caused by chemical carcinogens/mutagenswith a spccificity approaching that of the unscheduled DNA synthesis assay. 展开更多
关键词 ADP-ribosyl TRANSFERASE NAD CONTENT SHORT-term test MUTAGEN
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The Mid-Term Model Forecast Test of North China Rainstorm from July 19th to 20th, 2016
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作者 Xiakun Zhang Qiqi Liu Manyu Zhang 《Journal of Geoscience and Environment Protection》 2017年第8期166-180,共15页
Heavy rain is a kind of severe weather, often causing floods and serious soil erosion, leading to engineering losses, embankment rupture and crop flooding and other significant economic losses. Especially for some low... Heavy rain is a kind of severe weather, often causing floods and serious soil erosion, leading to engineering losses, embankment rupture and crop flooding and other significant economic losses. Especially for some low-lying terrain areas, rainwater cannot quickly vent caused by farm water and soil moisture being too saturated, so it will cause more geological disasters. This article combines live and forecast data, aiming at the results of the mid-rainstorm forecast in North China during the period of 7.19-2016, and compares with the actual situation of rainstorm. We carry out the mid-term forecast of the rainstorm. The atmosphere is a kind of medium with various fluctuation phenomena, and its physical properties and changes are studied by the analysis of volatility which is an important research method. It is important to improve the accuracy of such severe weather forecasting rainstorms and to take precautionary measures in a timely manner to minimize the losses caused by rainstorms. 展开更多
关键词 Heavy Rain North China Medium-term Model FORECAST test
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基于Overlay Test评价应力吸收层抗反射裂缝性能 被引量:18
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作者 颜可珍 王绍全 +2 位作者 田珊 陈景豪 孙皓 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2020年第1期108-115,共8页
为了更好地评价应力吸收层的抗反射裂缝性能,提出采用Overlay Test(OT)试验测定SBS、WTR和WTR/APAO改性沥青应力吸收层在常规条件、浸水和长期老化后的抗反射裂缝性能.研究发现,试验周期数、荷载损失率和总断裂能能够很好地表征应力吸... 为了更好地评价应力吸收层的抗反射裂缝性能,提出采用Overlay Test(OT)试验测定SBS、WTR和WTR/APAO改性沥青应力吸收层在常规条件、浸水和长期老化后的抗反射裂缝性能.研究发现,试验周期数、荷载损失率和总断裂能能够很好地表征应力吸收层的抗反射裂缝性能;第一周期最大荷载和临界断裂能是评价初期开裂的指标.试验发现3种应力吸收层在常规条件下均有良好的抗反射裂缝性能,但是水损坏对WTR/APAO的抗裂性能影响较大,长期老化后WTR和WTR/APAO的抗反射裂缝性能大大降低.3种应力吸收层的OT试验最大荷载-周期数曲线符合幂函数变化规律. 展开更多
关键词 应力吸收层 反射裂缝 Overlay test 水损坏 长期老化 沥青混合料
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基于LDRA TESTBED的汇编语言软件测试方法研究 被引量:2
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作者 尤艺 《航天控制》 CSCD 北大核心 2004年第5期77-81,共5页
在航天型号软件的开发过程中 ,充分的测试是软件质量和可靠性的必要保证。本文以软件代码分析工具─LDBATESTBED为背景 ,详细阐述了汇编程序的单元测试方法 。
关键词 单元测试 静态测试分析 动态测试分析 软件质量度量
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An improved four-dimensional variation source term inversion model with observation error regularization
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作者 Chao-shuai Han Xue-zheng Zhu +3 位作者 Jin Gu Guo-hui Yan Xiao-hui Gao Qin-wen Zuo 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期349-360,共12页
Aiming at the Four-Dimensional Variation source term inversion algorithm proposed earlier,the observation error regularization factor is introduced to improve the prediction accuracy of the diffusion model,and an impr... Aiming at the Four-Dimensional Variation source term inversion algorithm proposed earlier,the observation error regularization factor is introduced to improve the prediction accuracy of the diffusion model,and an improved Four-Dimensional Variation source term inversion algorithm with observation error regularization(OER-4DVAR STI model)is formed.Firstly,by constructing the inversion process and basic model of OER-4DVAR STI model,its basic principle and logical structure are studied.Secondly,the observation error regularization factor estimation method based on Bayesian optimization is proposed,and the error factor is separated and optimized by two parameters:error statistical time and deviation degree.Finally,the scientific,feasible and advanced nature of the OER-4DVAR STI model are verified by numerical simulation and tracer test data.The experimental results show that OER-4DVAR STI model can better reverse calculate the hazard source term information under the conditions of high atmospheric stability and flat underlying surface.Compared with the previous inversion algorithm,the source intensity estimation accuracy of OER-4DVAR STI model is improved by about 46.97%,and the source location estimation accuracy is improved by about 26.72%. 展开更多
关键词 Source term inversion Four dimensional variation Observation error regularization factor Bayesian optimization SF6 tracer test
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Are “Straight to Test” Pathways Always Best for Patients? A Prospective Observational Study of Two-Week-Wait Colorectal Referrals
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作者 Frances Mosley Jon R. Ausobsky John P. Griffith 《Surgical Science》 2013年第10期443-447,共5页
Aim: Many centres have adopted a straight to test approach to deliver a fast-track service for suspected lower GI cancer. We undertook a prospective comparison between patients having a straight to test (STT) flexible... Aim: Many centres have adopted a straight to test approach to deliver a fast-track service for suspected lower GI cancer. We undertook a prospective comparison between patients having a straight to test (STT) flexible sigmoidoscopy and those attending an outpatient appointment (OPA). The study aimed to determine whether STT reduced diagnostic time without additional investigations. Methods: An observational study of 200 consecutive fast-track colorectal referrals was undertaken. Data collected included: patient demographics, whether STT or OPA, investigations undertaken (including dates) and final diagnosis. Outcomes were compared by adjusted linear regression and logistic regression, for numerical and binary outcomes respectively. Potential confounding factors included were: age, gender and whether NICE referral criteria were achieved. Results: 186 out of 200 referrals attended their appointment, 62% (116/186) went STT and 38% (70/186) had an OPA. No significant difference was seen in the number of days to final investigation, adjusted coefficient -3.71, 95% C.I. -8.92 to 1.50. The STT group had 0.4 more tests per patient, adjusted 95% C.I. 0.07 to 0.73, than the OPA group. Significantly more patients in the STT group had a flexible sigmoidoscopy in addition to whole colonic imaging (all modalities), compared to the OPA group, adjusted OR of 93.47 (95% C.I. 29.26 to 298.54). Conclusion: This study highlights the potential disadvantages of STT flexible sigmoidoscopy for patients referred under the two-week-rule with suspected lower GI cancer. Despite the previously published work highlighting the potential cost and time benefits, it may come at the sacrifice of exposing patients to additional investigations. 展开更多
关键词 COLORECTAL Neoplasms (MeSH) Endoscopy Gastrointestinal (MeSH) COLORECTAL Surgery (MeSH) 2-Week-Wait Fast-Track STRAIGHT to test (No MESH term)
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Short-Term Precipitation Forecasting Rolling Update Correction Technology Based on Optimal Fusion Correction
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作者 Meijin Huang Qing Lin +4 位作者 Ning Pan Nengzhu Fan Tao Jiang Qianshan He Lingguang Huang 《Journal of Geoscience and Environment Protection》 2019年第3期145-159,共15页
In order to improve the availability of regional model precipitation forecast, this project intends to use the measured heavy rainfall data of dense automatic stations to carry out historical precipitation in the high... In order to improve the availability of regional model precipitation forecast, this project intends to use the measured heavy rainfall data of dense automatic stations to carry out historical precipitation in the high resolution: the Severe Weather Automatic Nowcast System (SWAN) quantitative precipitation forecast and the High-Resolution Rapid Refresh (HRRR) regional numerical model precipitation forecast in short-term nowcasting aging. Based on the error analysis, the grid fusion technology is used to establish the measured rainfall, HRRR regional model precipitation forecast, and optical flow radar quantitative precipitation forecast (QPF) three-source fusion correction scheme, comprehensively integrate the revised forecasting effect, adjust the fusion correction parameters, establish an optimal correction plan, generate a frozen rolling update revised product based on measured dense data and short-term forecast, and put it into business operation, and perform real-time effect rolling test evaluation on the forecast product. 展开更多
关键词 OPTIMAL FUSION CORRECTION Radar QPF Numerical Model SHORT-term Precipitation Forecasting ROLLING test
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某核燃料循环火灾事故研究装置及初步研究成果介绍
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作者 孙洪超 连一仁 +5 位作者 李国强 陈磊 孟东原 孙树堂 庄大杰 张建岗 《辐射防护》 CAS CSCD 北大核心 2024年第4期430-436,共7页
火灾事故作为核燃料循环设施典型事故,是国际核燃料循环安全领域研究的焦点。中国辐射防护研究院目前建有小、中、大三个尺度的核燃料循环火灾事故放射性源项研究装置。小尺度装置为200 L圆柱体燃烧舱室,主要用于可燃物基础参数测试;中... 火灾事故作为核燃料循环设施典型事故,是国际核燃料循环安全领域研究的焦点。中国辐射防护研究院目前建有小、中、大三个尺度的核燃料循环火灾事故放射性源项研究装置。小尺度装置为200 L圆柱体燃烧舱室,主要用于可燃物基础参数测试;中尺度装置和大尺度装置分别为20 m^(3)、120 m^(3)长方体燃烧舱室,主要用于开展可燃物燃烧速率、温度分布、放射性气体与气溶胶释放份额、核素释放份额和过滤效率等科学研究。重点对三套装置各自的特征和研究能力进行总结,结合国际研究热点提出了进一步研究计划。 展开更多
关键词 核燃料循环 火灾事故 实验装置 放射性源项
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俄罗斯液体潜射弹道导弹长期贮存材料工艺技术
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作者 王骁骞 赵峥嵘 吴小宁 《宇航材料工艺》 CAS CSCD 北大核心 2024年第4期131-136,共6页
对液体潜射弹道导弹长期加注贮存技术的发展进程、最新进展及研究现状进行概述。重点介绍俄罗斯液体潜射弹道导弹的结构设计、材料选取和制造工艺以及出厂加注封装和密封性检测方法,最后指出实现长期加注贮存的技术路径。
关键词 长期贮存 相容性 密封性 结构 材料 焊接工艺 封装 检测
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传统过夜受精与短时受精在继发不孕患者体外受精中的应用效果比较
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作者 吴成亮 苏占营 +2 位作者 江旺航 辜敏 巢时斌 《当代医学》 2024年第5期123-127,共5页
目的探讨传统过夜受精与短时受精在继发不孕患者体外受精中的应用效果。方法回顾性分析2019年1月至2021年10月于九江市妇幼保健院生殖中心因不孕不育进行体外受精-胚胎移植(IVF-ET)助孕的462个周期继发患者的临床资料,根据不同IVF方案... 目的探讨传统过夜受精与短时受精在继发不孕患者体外受精中的应用效果。方法回顾性分析2019年1月至2021年10月于九江市妇幼保健院生殖中心因不孕不育进行体外受精-胚胎移植(IVF-ET)助孕的462个周期继发患者的临床资料,根据不同IVF方案分为短时受精组[239个周期,胞浆内单精子显微注射(ICSI)周期除外]与传统过夜受精组(223个周期,ICSI周期除外)。两组移植周期均为49个周期。比较两组受精情况、两原核(2PN)率、卵裂率、优胚率、囊胚形成率、优质囊胚率、胚胎利用率及临床妊娠率等情况。结果两组MⅡ卵率、0PN率、1PN率、≥3PN率比较差异无统计学意义;传统过夜受精组2PN率高于短时受精组,差异有统计学意义(P<0.05)。两组卵裂率、优胚率、囊胚形成率、优质囊胚率、胚胎利用率、临床妊娠率比较差异无统计学意义;传统过夜受精组受精率高于短时受精组,差异有统计学意义(P<0.05)。结论传统过夜受精可作为继发不孕患者首选受精方式之一,可以提高卵子利用率及受精率,且不影响胚胎发育质量。 展开更多
关键词 继发性不孕 传统过夜受精 短时受精 试管婴儿
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基于K均值聚类算法和LSTM神经网络的管道腐蚀阶段预测方法
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作者 王新颖 刘岚 +2 位作者 陈海群 胡磊磊 谢逢豪 《腐蚀与防护》 CAS CSCD 北大核心 2024年第8期84-89,共6页
针对声发射检测获得的管道腐蚀信号,提出了一种基于K均值(K-means)聚类算法和长短期记忆(LSTM)神经网络的管道腐蚀阶段预测方法。首先,利用K-means聚类算法将腐蚀信号分类,再构建LSTM神经网络模型,并采取了无监督学习的方式,以声发射波... 针对声发射检测获得的管道腐蚀信号,提出了一种基于K均值(K-means)聚类算法和长短期记忆(LSTM)神经网络的管道腐蚀阶段预测方法。首先,利用K-means聚类算法将腐蚀信号分类,再构建LSTM神经网络模型,并采取了无监督学习的方式,以声发射波形为出发点,对模型进行参数优化,最后进行管道腐蚀阶段预测,并根据评价指标对模型进行评价。研究表明:对LSTM神经网络模型适当增加隐藏层,可以使得模型更加稳定,鲁棒性更好;与现有故障诊断模型相比,LSTM神经网络模型的精度更高。 展开更多
关键词 声发射无损检测 腐蚀阶段预测 K-MEANS聚类算法 长短期记忆(LSTM)神经网络 鲁棒性
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基于普洱茶中重金属成分检测标准物质长期稳定性的研究
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作者 杨春凤 李志娟 +2 位作者 段凤敏 孙力元 高林春 《计量与测试技术》 2024年第3期39-41,44,共4页
本文对所研发的普洱茶中重金属成分检测标准物质的长期稳定性进行了研究,阐述了该标准物质长期稳定性的研究理论及方法。该研究引用经典稳定性评估方案,采用电感耦合等离子体质谱方法,应用标准曲线分析规则(内标法),对普洱茶中Cr、Cu、C... 本文对所研发的普洱茶中重金属成分检测标准物质的长期稳定性进行了研究,阐述了该标准物质长期稳定性的研究理论及方法。该研究引用经典稳定性评估方案,采用电感耦合等离子体质谱方法,应用标准曲线分析规则(内标法),对普洱茶中Cr、Cu、Cd等重金属元素成分检测标准物质的长期稳定性进行了考察。结果表明:该实验可用于检验普洱茶中重金属成分检测标准物质的性能与品质。 展开更多
关键词 普洱茶 重金属 标准物质 长期稳定性 检验
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基于深度学习的隧道火灾火源位置和热释放速率反演
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作者 蒋立 何廷全 +1 位作者 郭鑫 阳东 《消防科学与技术》 CAS 北大核心 2024年第9期1292-1297,1315,共7页
火源位置和热释放速率(HRR)是指导隧道火灾消防应急救援的重要信息。但在实际中,得到的关于火场的信息十分有限,很难直接得到火源关键信息。提出了一种基于深度学习的隧道火灾火源位置和HRR的反演方法。首先,基于试验数据验证的数值模... 火源位置和热释放速率(HRR)是指导隧道火灾消防应急救援的重要信息。但在实际中,得到的关于火场的信息十分有限,很难直接得到火源关键信息。提出了一种基于深度学习的隧道火灾火源位置和HRR的反演方法。首先,基于试验数据验证的数值模拟建立不同边界条件下的隧道火灾数据集。基于卷积神经网络(CNN)和长短期记忆网络(LSTM)建立有限的固定式传感器温度数据和火源位置及HRR之间的映射关系,评估了该模型对于火源位置和HRR的反演效果。评估了时间输入步长和传感器间距对该模型反演性能的影响。结果表明,该模型对HRR和火源位置都有较好的反演性能,当时间输入步长为20 s,传感器间距为30 m时,模型反演HRR和火源位置的R2值分别为0.97和0.99。 展开更多
关键词 隧道火灾 数值模拟 火灾试验 长短期记忆网络 热释放速率 深度学习
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长期浸泡环境下复合磷酸镁水泥耐硫酸盐侵蚀性能研究
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作者 贾亮 陈岑 《甘肃科学学报》 2024年第5期146-152,共7页
为提高磷酸镁水泥(MPC)的耐水性和耐硫酸盐侵蚀性能以及降低施工成本,在MPC中掺入一定量的铁铝酸盐水泥(FAC)制备出新型MPC-FAC复合水泥。通过测试经历标准养护28 d,又分别在清水和5%Na_(2)SO_(4)溶液中浸泡不同龄期后的MPC-FAC砂浆试... 为提高磷酸镁水泥(MPC)的耐水性和耐硫酸盐侵蚀性能以及降低施工成本,在MPC中掺入一定量的铁铝酸盐水泥(FAC)制备出新型MPC-FAC复合水泥。通过测试经历标准养护28 d,又分别在清水和5%Na_(2)SO_(4)溶液中浸泡不同龄期后的MPC-FAC砂浆试件的质量损失情况、抗压强度和抗折强度,与相同环境下的MPC砂浆试件进行比较,借助SEM-EDS分析长期浸泡的MPC和MPC-FAC砂浆的微观形貌和化学元素组成。研究结果表明,FAC质量分数为38%时MPC-FAC砂浆的质量损失率最小,抗压强度和抗折强度最高,耐水性和耐硫酸盐侵蚀性能最强;加入适量FAC使得MPC-FAC砂浆的密实性得到提高,显著提升了MPC-FAC砂浆的耐水性和耐硫酸盐侵蚀性。 展开更多
关键词 磷酸镁水泥 铁铝酸盐水泥 砂浆 长期浸泡试验 耐硫酸盐侵蚀性能
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一种滑动检测算法下的滑坡位移时序分解方法 被引量:1
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作者 冯谕 曾怀恩 涂鹏飞 《长江科学院院报》 CSCD 北大核心 2024年第3期126-133,147,共9页
针对“阶跃式”滑坡位移时序分解模型力学解释性不强的缺陷,根据西原蠕变本构模型与自适应改进遗传算法模型,提出滑动R_(nl)阶跃点检测方法与改进加权移动平均修正阶跃项位移方法,并将该方法应用于白水河滑坡位移时序分解。将滑动R_(nl... 针对“阶跃式”滑坡位移时序分解模型力学解释性不强的缺陷,根据西原蠕变本构模型与自适应改进遗传算法模型,提出滑动R_(nl)阶跃点检测方法与改进加权移动平均修正阶跃项位移方法,并将该方法应用于白水河滑坡位移时序分解。将滑动R_(nl)阶跃点检测结果与MK检验结果、滑动t检验结果以及Bayes检测结果作对比。结果表明,滑动R_(nl)阶跃点检测结果更加准确与适用;同时将新型滑坡位移时序分解结果与二次移动平均时序分解结果、三次指数平滑时序分解结果以及VMD时序分解结果作对比。结果表明,新型滑坡位移时序分解方法解决了滑坡趋势项位移无规律、无力学解释性的问题,且在时序分解加法模式中单独引入滑坡位移预测中最重要的阶跃项位移,分析预测更具有针对性。因此,新型时序分解模型有一定的工程价值与时序预测借鉴价值。 展开更多
关键词 滑坡位移 时序分解 阶跃项位移 蠕变模型 遗传算法 滑动检测
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医院制剂白色洗剂稳定性的初步研究
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作者 杨晓峰 李惠英 秦利芬 《儿科药学杂志》 CAS 2024年第7期5-8,共4页
目的:考察医院制剂白色洗剂于不同贮存条件下进行加速实验和长期实验,制剂稳定性随贮存时间延长的变化情况,为该制剂的贮存方式、使用时间和生产工艺提供依据,通过实验进一步预测其贮存有效期。方法:根据《中国药典》2020年版第四部900... 目的:考察医院制剂白色洗剂于不同贮存条件下进行加速实验和长期实验,制剂稳定性随贮存时间延长的变化情况,为该制剂的贮存方式、使用时间和生产工艺提供依据,通过实验进一步预测其贮存有效期。方法:根据《中国药典》2020年版第四部9001原料药物与制剂稳定性试验指导原则,对3批白色洗剂进行加速实验和长期实验研究,按照制剂质量标准对该制剂的性状、成分鉴别、苯酚含量、氧化锌含量及微生物限度进行检查,利用Minitab 21软件进行数据分析,考察白色洗剂的稳定性。结果:(1)加速实验结果表明,在温度(42±2)℃、相对湿度75%±5%条件下贮存6个月,白色洗剂的理化性质和主要成分含量符合质量标准,微生物限度符合规定;(2)长期实验结果表明,在温度(25±2)℃,相对湿度60%±10%条件下贮存36个月,白色洗剂的理化性质、微生物限度符合规定,氧化锌含量符合质量标准,苯酚含量从第18个月开始检测时低于限度值。结论:通过Minitab 21软件对加速实验、长期实验结果进行数据分析,白色洗剂常温(10~30℃)贮存,有效期可定为9个月。 展开更多
关键词 长期试验 加速试验 稳定性 有效期
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导弹长期复杂环境适应性加速试验设计方法
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作者 王增凯 刘艳 +3 位作者 陈江攀 刘艺 孙立敏 孙一凡 《装备环境工程》 CAS 2024年第7期28-35,共8页
目的针对工程界缺乏长期气候与力学环境耦合效应的验证与评价方法,提出导弹长期复杂环境适应性加速试验剖面设计方法,支持长期、复杂环境耐受能力评价。方法根据寿命剖面和环境剖面,辨识产品敏感环境应力,开展环境应力数据收集,在构建... 目的针对工程界缺乏长期气候与力学环境耦合效应的验证与评价方法,提出导弹长期复杂环境适应性加速试验剖面设计方法,支持长期、复杂环境耐受能力评价。方法根据寿命剖面和环境剖面,辨识产品敏感环境应力,开展环境应力数据收集,在构建常规应力试验剖面的基础上,针对气候类、力学类环境应力分别提出加速因子建模方法,最终转化生成多应力综合加速试验剖面。结果以导弹舵系统为对象,运用本文方法进行了长期复杂环境适应性加速试验剖面设计,应用表明,本方法可在较短时间内有效暴露长期复杂环境下的薄弱环节,且与实际失效模式一致。结论该方法充分考虑了导弹寿命期内经受的复杂环境因素,能够模拟高温、湿热、盐雾、温度循环等气候类环境应力和力学环境应力共同作用下的长期缓变耦合效应,支持导弹长期复杂环境适应性的快速评价,可在工程应用中推广。 展开更多
关键词 导弹 长期复杂环境适应性 加速试验 气候环境 力学环境 环境效应
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