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Study on smoke propagation in tunnel construction of a hydropower station: A full-scale fire experiment

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Journal of Safety Science and Resilience 2023年第2期4卷 188-202页

作者： Chang Liu Huihang Cheng wenjun nie Senlin Jiang Junfeng Chen Peng Lin Maohua Zhong Institute of Public Safety Research Departnent of Engineering PhysicsTsinghua UniverstyBeijing 100084China China Electric Power Research Institute Beijing 100192China Sinohydro Bureau 6 Co. LTDShenyang 110179China Department of Hydraulic Engineering Tsinghua UniversityBeijing 100084China

In this study,full-scale fire experiments were conducted in a hydropower station to investigate smoke propagation during tunnel construction.The flame height,smoke temperature and stratification,smoke descent and spread velocity were analyzed via measurements and on-site observations.The initial combustion stage was largely affected by ignition source during tunnel construction for diesel pool fire,and the average flame height in the fully developed stage could reach 1.4-2.1 m in experimental fire scenarios.The gradient of the smoke temperature evolution near the fire was the opposite for the upstream and downstream regions.The longitudinal temperature distribution was concentrated in a small range at the heights of the smoke layer,and gradually decreased by air entrainment as the height decreased,while further increasing in the lower half of the tunnel height in the near-fire region under heat radiation from the fire source.Moreover,distinct and stable smoke stratification formed during the fully developed combustion stage,and the smoke layer interface was at approximately half the tunnel height.Smoke descent was aggravated in the decay stage of combustion,and the fire risk remained high after the fully developed period.The smoke front spread velocity was empirically determined for the full-scale tunnel fire scenarios.Conclusions from full-scale experiments can support smoke control design and on-site fire emergency response plans for hydropower stations.

关键词： Full-scale experiment Fire Smoke propagation Construction tunnel Hydropowerstation

各向异性层状千枚岩渗透率及有效孔隙率试验研究

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岩土工程学报 2024年第2期46卷 445-451页

作者：王伟陈超维刘世藩曹亚军段雪雷聂文俊河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210024 河海大学岩土工程科学研究所江苏南京210024 中国水利水电第六工程局有限公司辽宁沈阳110013

采用岩石全自动三轴伺服仪和气体渗透装置,对一种致密的各向异性层状千枚岩开展了气体渗透率及有效孔隙率试验,研究常规三轴压缩和围压循环加卸载2种应力路径下,气体渗透率、有效孔隙率随层理倾角及偏应力的演化规律。结果表明:围压相同... 详细信息

采用岩石全自动三轴伺服仪和气体渗透装置,对一种致密的各向异性层状千枚岩开展了气体渗透率及有效孔隙率试验,研究常规三轴压缩和围压循环加卸载2种应力路径下,气体渗透率、有效孔隙率随层理倾角及偏应力的演化规律。结果表明:围压相同时,岩样的初始气体渗透率k0随着层理倾角β的增大呈“W”型变化,在β=45°时取最大值;在围压循环加卸载过程中,气体渗透率先随围压的加载而减小,后随围压的卸载而增大,卸载时的气体渗透率小于加载时的渗透率;层状千枚岩有效孔隙率和气体渗透率呈指数关系;平行于层理方向的气体渗透率远大于垂直于层理方向的气体渗透率;岩样有效孔隙率和气体渗透率随偏应力变化经历初始压密阶段、线弹性阶段和塑性变形阶段,随着偏应力的增大,岩样有效孔隙率和气体渗透率先减小,接着保持稳定,最后快速增大,并在岩样应力-应变曲线斜率接近于0时达到最大值。

关键词：层状岩石各向异性气体渗透率有效孔隙率常规三轴压缩围压循环加卸载

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不同生态修复草种对土壤水分蒸散的影响

北方园艺 2024年第3期 71-78页

作者：孙铁军聂明鹤滕文军侯新村北京市农林科学院草业花卉与景观生态研究所北京100097

以紫花苜蓿、结缕草、青绿苔草和无芒雀麦为试材,通过人工草地建植对退化植被进行生态修复,实时监测植被NDVI指数、根系体积、土壤含水量及水分蒸散动态变化,研究不同草种植被覆盖效果及其对土壤蒸散特征的影响,揭示植被土壤水分吸收的... 详细信息

以紫花苜蓿、结缕草、青绿苔草和无芒雀麦为试材,通过人工草地建植对退化植被进行生态修复,实时监测植被NDVI指数、根系体积、土壤含水量及水分蒸散动态变化,研究不同草种植被覆盖效果及其对土壤蒸散特征的影响,揭示植被土壤水分吸收的主要作用机理,以期为我国北方地区适宜生态修复草种选择提供参考依据。结果表明:4种生态修复草种均可快速增加植被生物量,减少非生长季土壤水分蒸散,但生长季植被生物量增加,土壤水分吸收增强,土壤蒸散明显增加,且不同草地月蒸散量峰值排序为青绿苔草(112.65 mm)>结缕草(107.42 mm)>紫花苜蓿(98.19 mm)>无芒雀麦(86.69 mm)。另外,植被根系分布及其体积变化是土壤水分吸收的关键,根系体积越大,分布越集中,土壤水分吸收能力越强,其中,青绿苔草与结缕草土壤水分吸收的主要区域在0~20 cm土层,紫花苜蓿与无芒雀麦在20~40 cm土层。综上所述,由于生长季植被增加土壤水分蒸散,建议北方干旱缺水地区生态修复过程中尽量选择水土保持能力强但水分消耗相对较少的植物种类,就供试植物优先选择无芒雀麦,其次是紫花苜蓿。

关键词：生态修复草种土壤蒸散生物量根系水分吸收

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重组分处置回收对四氯乙烯产品质量的影响

中国氯碱 2024年第5期 12-16页

作者：王文俊聂勇徐涛泸州鑫福化工股份有限公司四川泸州

介绍了四氯乙烯生产中精馏釜液重组分的回收和六氯乙烷的提纯工艺,阐述了残液回收对产品质量的影响及采取的措施。

关键词：重组分四氯乙烯回收产品质量

基于网络药理学和分子对接探讨八珍汤治疗乳腺癌的作用机制

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现代医药卫生 2024年第6期40卷 923-929页

作者：党文军聂宏刘爽孔祥颖姜雨微黑龙江中医药大学黑龙江佳木斯154007 佳木斯大学黑龙江佳木斯154007

目的基于网络药理学和分子对接探讨八珍汤防治乳腺癌的分子机制。方法利用数据平台筛选八珍汤活性成分,利用数据库筛选乳腺癌相关靶点。以软件构建“药物-化合物-靶点”网络,并用分子对接验证有效成分与靶点亲和力。结果筛选出八珍汤有... 详细信息

目的基于网络药理学和分子对接探讨八珍汤防治乳腺癌的分子机制。方法利用数据平台筛选八珍汤活性成分,利用数据库筛选乳腺癌相关靶点。以软件构建“药物-化合物-靶点”网络,并用分子对接验证有效成分与靶点亲和力。结果筛选出八珍汤有效成分2336个,潜在靶点211个。分子对接结果显示活性成分槲皮素、柚皮素、山柰酚与关键靶点ATK1、CASP3具有良好亲和力。结论初步明确八珍汤治疗乳腺癌的作用机制是通过山柰酚、槲皮素、柚皮素等活性成分作用于AKT1、CASP3等关键靶点。

关键词：八珍汤乳腺癌网络药理学机制预测分子对接

Genotoxicity of drinking water treated with different disinfectants and effects of disinfection conditions detected by umu-test

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Journal of Environmental Sciences 2017年第6期29卷 36-44页

作者： Xuebiao nie wenjun Liu Liping Zhang Qing Liu Division of Drinking Water Safety School of EnvironmentTsinghua UniversityBeijing 100084China

The genotoxieity of drinking water treated with 6 disinfection methods and the effects of disinfection conditions were investigated using the urea-test The pretreatment procedure of samples for the urea-test was optimized for drinking water analysis. The results of the urea-test were in good correlation with those of the Ames-test The genotoxicity and production of haloacetic acids （HAAs） were the highest for chlorinated samples. UV ＋ chloramination is the safest disinfection method from the aspects of genotoxicity, HAA production and inactivation effects. For chloramination, the effects of the mass ratio of C12 to N of chloramine on genotoxicity were also studied. The changes of genotoxicity were different from those of HAA production, which implied that HAA production cannot represent the genotoxic potential of water. The genotoxicity per chlorine decay of chlorination and chloramination had similar trends, indicating that the reaction of organic matters and chlorine made a great contribution to the genotoxicity. The results of this study are of engineering significance for optimizing the operation of waterworks.

关键词： CenotoxicityDrinking waterChlorineUVDisinfectionumu-test

不同植物空间类型康养步道五感体验因子质量综合研究

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中国城市林业 2024年第1期22卷 94-102页

作者：孙芸浩聂庆娟艾洪彦孙玉竹王茜段文军北京市园林绿化科学研究院北京100102 河北农业大学河北保定071000 北京京林一诚园林景观工程有限公司北京250000 北京市西城区公园管理中心北京100044 北京市园林古建设计研究院有限公司北京100000

随着我国经济社会的快速发展,身体亚健康、人口老龄化等问题日益严重,人们崇尚绿色、向往自然,追求健康的愿望日益迫切。文章通过对比分析北京西山国家森林公园春秋两季4种植物空间类型下康养步道内五感体验因子质量优劣,探究其对人体... 详细信息

随着我国经济社会的快速发展,身体亚健康、人口老龄化等问题日益严重,人们崇尚绿色、向往自然,追求健康的愿望日益迫切。文章通过对比分析北京西山国家森林公园春秋两季4种植物空间类型下康养步道内五感体验因子质量优劣,探究其对人体健康的有效性,得出最适于康养的植物空间类型,以提高植物空间的设计质量和使用效果,促进森林康养高质量发展。结果表明:在触觉因子方面,受温湿度影响,两季舒适度日变化趋势存在差异,而植物空间类型上均为垂直空间最好,开敞空间最差。在嗅觉因子方面,两季空气负离子浓度日变化均为先降后升的趋势,而在两季各植物空间类型五感体验优劣排序中,嗅觉和视觉因子均为覆盖空间>半开敞空间>垂直空间>开敞空间。在听觉因子方面,两季声环境适宜性均为覆盖空间最好,开敞空间最差。在味觉因子方面,植物群落结构丰富且联觉感知最好的覆盖空间最优。综上,在森林康养步道中,五感体验最舒适的空间类型是覆盖空间,其次为半开敞空间,第三是垂直空间,最后为开敞空间。

关键词：西山国家森林公园植物空间类型康养步道五感体验

Fanconi anemia gene-associated germline predisposition in aplastic anemia and hematologic malignancies

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Frontiers of Medicine 2022年第3期16卷 459-466页

作者： Daijing nie Jing Zhang Fang Wang Xvxin Li Lili Liu Wei Zhang Panxiang Cao Xue Chen Yang Zhang Jiaqi Chen Xiaoli Ma Xiaosu Zhou Qisheng Wu Ming Liu Mingyue Liu wenjun Tian Hongxing Liu Division of Laboratory Medicine Hebei Yanda Lu Daopei HospitalLangfang 065201China Beijing Lu Daopei Institute of Hematology Beijing 100176China Division of Pathology&Laboratory Medicine Beijing Lu Daopei HospitalBeijing 100176China Department of Clinical Laboratory Medicine Shandong Provincial Hospital Affiliated to Shandong UniversityJinan 250021China

Whether Fanconi anemia(FA)heterozygotes are predisposed to bone marrow failure and hematologic neoplasm is a crucial but unsettled issue in cancer prevention and family consulting.We retrospectively analyzed rare possibly significant variations(PSVs)in the five most obligated FA genes,BRCA2,FANCA,FANCC,FANCD2,and FANCG,in 788 patients with aplastic anemia(AA)and hematologic malignancy.Sixty-eight variants were identified in 66 patients(8.38%).FANCA was the most frequently mutated gene(n=29),followed by BRCA2(n=20).Compared with that of the ExAC East Asian dataset,the overall frequency of rare PSVs was higher in our cohort(P=0.016).BRCA2 PSVs showed higher frequency in acute lymphocytic leukemia(P=0.038),and FANCA PSVs were significantly enriched in AA and AML subgroups(P=0.020;P=0.008).FA-PSV-positive MDS/AML patients had a higher tumor mutation burden,higher rate of cytogenetic abnormalities,less epigenetic regulation,and fewer spliceosome gene mutations than those of FA-PSV-negative MDS/AML patients(P=0.024,P=0.029,P=0.024,and P=0.013).The overall PSV enrichment in our cohort suggests that heterozygous mutations of FA genes contribute to hematopoietic failure and leukemogenesis.

关键词： Fanconi anemia aplastic anemia hematologic malignancy germline predisposition

Efficacy and safety of early anticoagulation after endovascular treatment in patients with atrial fibrillation

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Stroke & Vascular Neurology 2023年第5期8卷 405-412,I0017-I0023页

作者： Yaning Xu Chengchun Liu Wei Li Ximing nie Shuhan Huang Xiaoshu Li Ya Wu Wang-Sheng Jin Jiaojin Jiang Jun Dong Yi Yang Zhiqiang Sun wenjun Han Yanjiang Wang Liping Liu Meng Zhang Department of Neurology Army Medical Center of PLAArmy Medical UniversityChongqingChina Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases BeijingChina

Background The timing for initiating anticoagulant therapy in acute ischaemic stroke(AIS)patients with atrial fibrillation who recanalised after endovascular treatment(EVT)is unclear.The objective of this study was to evaluate the effect of early anticoagulation after successful recanalisation in AIS patients with atrial fibrillation.Methods Patients with anterior circulation large vessel occlusion and atrial fibrillation who were successfully recanalised by EVT within 24 hours after stroke in the Registration Study for Critical Care of Acute Ischemic Stroke after Recanalization registry were analysed.Early anticoagulation was defined as the initiation of unfractionated heparin(UFH)or low-molecular-weight heparin(LMWH)within 72 hours after EVT.Ultra-early anticoagulation was defined if it was initiated within 24 hours.The primary efficacy outcome was the score on the modified Rankin Scale(mRS)at day 90,and the primary safety outcome was symptomatic intracranial haemorrhage within 90 days.Results Overall,257 patients were enrolled,of whom 141(54.9%)initiated anticoagulation within 72 hours after EVT,including 111 within 24 hours.A significant shift towards better mRS scores at day 90 was associated with early anticoagulation(adjusted common OR 2.08(95%CI 1.27 to 3.41)).Symptomatic intracranial haemorrhage was comparable between patients treated with early and routine anticoagulation(adjusted OR 0.20(95%CI 0.02 to 2.18)).Comparison of different early anticoagulation regimens showed that ultra-early anticoagulation was more significantly associated with favourable functional outcomes(adjusted common OR 2.03(95%CI 1.20 to 3.44))and reduced the incidence of asymptomatic intracranial haemorrhage(OR 0.37(95%CI 0.14 to 0.94)).Conclusions In AIS patients with atrial fibrillation,early anticoagulation with UFH or LMWH after successful recanalisation is associated with favourable functional outcomes without increasing the risk of symptomatic intracranial haemorrhages.

关键词： patients fibrillation routine