期刊文献+
共找到19,260篇文章
< 1 2 250 >
每页显示 20 50 100
Inhibition of the NF-κB Signaling Pathway Improves Cigarette Mainstream Smoke-Induced Lung Injury and Gut Microbiota Disturbance
1
作者 Hong Huang Shengjie Li +6 位作者 Lifang Zeng Yan Zhang Ying Chen Yanbing Ma Jing Wei Changwei Zou Tingtao Chen 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第6期676-681,共6页
Currently,cigarette smoke(CS)remains a major contributor to disease morbidity and mortality.CS can be divided into cigarette mainstream smoke(CMS)and side-stream smoke,depending on where it is produced by burning toba... Currently,cigarette smoke(CS)remains a major contributor to disease morbidity and mortality.CS can be divided into cigarette mainstream smoke(CMS)and side-stream smoke,depending on where it is produced by burning tobacco^([1]).CMS is inhaled by smokers from the filter end during cigarette combustion and is strongly associated with the development of several diseases^([2-4]). 展开更多
关键词 smoke CMS CIGARETTE
下载PDF
Small-scale fire tests in the underwater tunnel section model with new sidewall smoke extraction
2
作者 Shunyu Yue Ruifeng Miao +2 位作者 Huihang Cheng Maohua Zhong Xiujun Yang 《Deep Underground Science and Engineering》 2024年第2期247-254,共8页
The Shenzhen–Zhongshan Bridge is a 24‐km‐long bridge and tunnel system,including a 6.8-km-long super cross section subsea tunnel.To solve the smoke exhaust problem of a super large cross-section subsea tunnel,the t... The Shenzhen–Zhongshan Bridge is a 24‐km‐long bridge and tunnel system,including a 6.8-km-long super cross section subsea tunnel.To solve the smoke exhaust problem of a super large cross-section subsea tunnel,the tunnel has a new smoke exhaust system that combines a horizontal smoke exhaust cross section at the top and sidewall smoke exhaust holes.In order to evaluate the potential fire hazards of this type of tunnel,a 1:30 tunnel model was established and 140 smallscale experiments on underwater tunnel fires were conducted.By changing the fire power,fire location,and fan operation mode,different scenarios of submarine immersed tunnel fire were simulated and the related key parameters such as fire smoke diffusion behavior and smoke temperature distribution were studied.On this basis,the optimal smoke control strategy was proposed for different fire scenarios.The research results indicate that the new smoke exhaust system can fully utilize the smoke flow characteristics,significantly improve smoke exhaust efficiency,and increase available evacuation time,thus further enhancing the fire safety of super large cross-section subsea tunnels. 展开更多
关键词 sidewall smoke extraction system small‐scale fire tests smoke control
下载PDF
An Improved YOLOv5s-Based Smoke Detection System for Outdoor Parking Lots
3
作者 Ruobing Zuo Xiaohan Huang +1 位作者 Xuguo Jiao Zhenyong Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第8期3333-3349,共17页
In the rapidly evolving urban landscape,outdoor parking lots have become an indispensable part of the city’s transportation system.The growth of parking lots has raised the likelihood of spontaneous vehicle combus-ti... In the rapidly evolving urban landscape,outdoor parking lots have become an indispensable part of the city’s transportation system.The growth of parking lots has raised the likelihood of spontaneous vehicle combus-tion,a significant safety hazard,making smoke detection an essential preventative step.However,the complex environment of outdoor parking lots presents additional challenges for smoke detection,which necessitates the development of more advanced and reliable smoke detection technologies.This paper addresses this concern and presents a novel smoke detection technique designed for the demanding environment of outdoor parking lots.First,we develop a novel dataset to fill the gap,as there is a lack of publicly available data.This dataset encompasses a wide range of smoke and fire scenarios,enhanced with data augmentation to ensure robustness against diverse outdoor conditions.Second,we utilize an optimized YOLOv5s model,integrated with the Squeeze-and-Excitation Network(SENet)attention mechanism,to significantly improve detection accuracy while maintaining real-time processing capabilities.Third,this paper implements an outdoor smoke detection system that is capable of accurately localizing and alerting in real time,enhancing the effectiveness and reliability of emergency response.Experiments show that the system has a high accuracy in terms of detecting smoke incidents in outdoor scenarios. 展开更多
关键词 YOLOv5s smoke detection deep learning SENet
下载PDF
U-Net Inspired Deep Neural Network-Based Smoke Plume Detection in Satellite Images
4
作者 Ananthakrishnan Balasundaram Ayesha Shaik +1 位作者 Japmann Kaur Banga Aman Kumar Singh 《Computers, Materials & Continua》 SCIE EI 2024年第4期779-799,共21页
Industrial activities, through the human-induced release of Green House Gas (GHG) emissions, have beenidentified as the primary cause of global warming. Accurate and quantitative monitoring of these emissions isessent... Industrial activities, through the human-induced release of Green House Gas (GHG) emissions, have beenidentified as the primary cause of global warming. Accurate and quantitative monitoring of these emissions isessential for a comprehensive understanding of their impact on the Earth’s climate and for effectively enforcingemission regulations at a large scale. This work examines the feasibility of detecting and quantifying industrialsmoke plumes using freely accessible geo-satellite imagery. The existing systemhas so many lagging factors such aslimitations in accuracy, robustness, and efficiency and these factors hinder the effectiveness in supporting timelyresponse to industrial fires. In this work, the utilization of grayscale images is done instead of traditional colorimages for smoke plume detection. The dataset was trained through a ResNet-50 model for classification and aU-Net model for segmentation. The dataset consists of images gathered by European Space Agency’s Sentinel-2 satellite constellation from a selection of industrial sites. The acquired images predominantly capture scenesof industrial locations, some of which exhibit active smoke plume emissions. The performance of the abovementionedtechniques and models is represented by their accuracy and IOU (Intersection-over-Union) metric.The images are first trained on the basic RGB images where their respective classification using the ResNet-50model results in an accuracy of 94.4% and segmentation using the U-Net Model with an IOU metric of 0.5 andaccuracy of 94% which leads to the detection of exact patches where the smoke plume has occurred. This work hastrained the classification model on grayscale images achieving a good increase in accuracy of 96.4%. 展开更多
关键词 smoke plume ResNet-50 U-Net geo satellite images early warning global monitoring
下载PDF
Unveiling the dynamic role of innate and adaptive immune cells in COPD pathogenesis induced by cigarette smoke
5
作者 Dur E Maknoon Razia Syed Sib Tul Hassan Shah Tabish Faheem 《Life Research》 2024年第4期29-41,共13页
Chronic obstructive pulmonary disease(COPD)is a multifaceted syndrome characterized by a dysregulated inflammatory cascade within the respiratory system,primarily triggered by exposure to harmful particles and gases,n... Chronic obstructive pulmonary disease(COPD)is a multifaceted syndrome characterized by a dysregulated inflammatory cascade within the respiratory system,primarily triggered by exposure to harmful particles and gases,notably from cigarette smoke.This inflammatory response is orchestrated by innate immune cells like macrophages and epithelial cells,which recognize danger signals released from damaged cells.Prolonged inflammation prompts an adaptive immune reaction mediated by dendritic cells,culminating in the formation of lymphoid follicles and involving a complex interplay of T and B cells,as well as cytotoxic activity.Additionally,both viral and bacterial infections exacerbate COPD by further igniting inflammatory pathways,perpetuating the chronic inflammatory state.This comprehensive review encapsulates the intricate interplay between innate and adaptive immunity in COPD,with a particular focus on the role of cigarette smoke in its pathogenesis and potential therapeutic targets. 展开更多
关键词 chronic obstructive pulmonary disease innate immunity adaptive immunity cigarette smoke inflammation oxidative stress protease-antiprotease imbalance
下载PDF
Pursuing a smoke-free generation
6
作者 Lawrence O Gostin 《四川生理科学杂志》 2024年第5期1094-1094,共1页
The United Kingdom may soon become a world leader in forging a smoke-free generation.Last month,the country passed a bill that bans the sale of cigarettes to anyone born in 2009 or later.The prime minister claims the ... The United Kingdom may soon become a world leader in forging a smoke-free generation.Last month,the country passed a bill that bans the sale of cigarettes to anyone born in 2009 or later.The prime minister claims the policy will"phase out smoking in young people almost completely as early as 2040."A final vote by Parliament is expected next month.Tobacco claims 8 million lives every year,and could claim a billion lives over this century-mostly in low-and middle-income countries.For every person that dies,at least 30 more suffer from smokingrelated chronic disease.The benefits of a tobacco-free society would be transformational. 展开更多
关键词 smoke INCOME CLAIMS
下载PDF
Study on the Anti-infrared Performance of Liquid Smoke Composition
7
作者 ZHOU Zun-ning YAN Fei +2 位作者 CUI Yu-ling LIU Wei-qiang MEI Qing-he 《含能材料》 EI CAS CSCD 2007年第3期294-294,296,共2页
In the technical field of reconnaissance, target location, target tracking and arms technology, IR sensors are increasingly used for making the entire battlefield transparent up to far into the opponents′ area.
关键词 复合材料 抗红外性能 烟雾剂 液体 烟幕
下载PDF
Impact of Smoke-Free Legislation on Acute Myocardial Infarction and Subtypes of Stroke Incidence in Shenzhen,China,2012-2016:An Interrupted Time Series Analysis 被引量:2
8
作者 SHI Yu Lin XIONG Jing Fan +3 位作者 LIU Li Qun ZHAO Zhi Guang WAN Xia PENG Ji 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第6期527-536,共10页
Objective This study assesses the impact of smoke-free legislation on the incidence rate for acute myocardial infarction(AMI)and stroke in Shenzhen.Methods Data on ischemic(n=72,945)and hemorrhagic(n=18,659)stroke and... Objective This study assesses the impact of smoke-free legislation on the incidence rate for acute myocardial infarction(AMI)and stroke in Shenzhen.Methods Data on ischemic(n=72,945)and hemorrhagic(n=18,659)stroke and AMI(n=17,431)incidence covering about 12 million people in Shenzhen from 2012 to 2016 were used.Immediate and gradual changes in incidence rates were analyzed using segmented Poisson regression.Results Following the smoke-free legislation,a 9%(95%CI:3%-15%)immediate reduction was observed in AMI incidence,especially in men(8%,95%CI:1%-14%)and in those aged 65 years and older(17%,95%CI:9%-25%).The gradual annual benefits were observed only in hemorrhagic and ischemic stroke incidence,with a 7%(95%CI:2%-11%)and 6%(95%CI:4%-8%)decrease per year,respectively.This health effect extended gradually to the 50-64 age group.In addition,neither the immediate nor gradual decrease in stroke and AMI incidence rates did not show statistical significance among the 35-49 age group(P>0.05).Conclusion Smoke-free legislation was enforced well in Shenzhen,which would generate good experiences for other cities to enact and enforce smoke-free laws.This study also provided more evidence of the health benefits of smoke-free laws on stroke and AMI. 展开更多
关键词 smoke-free legislation Second-hand smoke TOBACCO Myocardial infarction STROKE Prevention
下载PDF
The Association between Exposure to Second-Hand Smoke and Disease in the Chinese Population: A Systematic Review and Meta-Analysis 被引量:2
9
作者 WANG Yu Tong HU Kui Ru +7 位作者 ZHAO Jian AI Fei Ling SHI Yu Lin WANG Xue Wei YANG Wen Yi WANG Jing Xin AILiMei WAN Xia 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第1期24-37,共14页
Objective To analyze the association between exposure to second-hand smoke(SHS) and 23 diseases,categorized into four classifications, among the Chinese population.Methods We searched the literature up to June 30, 202... Objective To analyze the association between exposure to second-hand smoke(SHS) and 23 diseases,categorized into four classifications, among the Chinese population.Methods We searched the literature up to June 30, 2021, and eligible studies were identified according to the PECOS format: Participants and Competitors(Chinese population), Exposure(SHS),Outcomes(Disease or Death), and Study design(Case-control or Cohort).Results In total, 53 studies were selected. The odds ratio(OR) for all types of cancer was 1.79(1.56–2.05), and for individual cancers was 1.92(1.42–2.59) for lung cancer, 1.57(1.40–1.76) for breast cancer, 1.52(1.12–2.05) for bladder cancer, and 1.37(1.08–1.73) for liver cancer. The OR for circulatory system diseases was 1.92(1.29–2.85), with a value of 2.29(1.26–4.159) for stroke. The OR of respiratory system diseases was 1.76(1.13–2.74), with a value of 1.82(1.07–3.11) for childhood asthma. The original ORs were also shown for other diseases. Subgroup analyses were performed for lung and breast cancer. The ORs varied according to time period and were significant during exposure in the household;For lung cancer, the OR was significant in women.Conclusion The effect of SHS exposure in China was similar to that in Western countries, but its definition and characterization require further clarification. Studies on the association between SHS exposure and certain diseases with high incidence rates are insufficient. 展开更多
关键词 Second-hand smoke Chinese population CANCER Diseases of the respiratory system Diseases of the circulatory system Systematic review META-ANALYSIS
下载PDF
Line-of-sight rates extraction of roll-pitch seeker under anti-infrared decoy state
10
作者 LI Yue HE Lei XIA Qunli 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第1期178-196,共19页
In this paper,the method of extracting guidance information such as the line-of-sight(LOS)rates under the anti-infrared decoy state for the roll-pitch seeker is researched.Coordinate systems which are used to describe... In this paper,the method of extracting guidance information such as the line-of-sight(LOS)rates under the anti-infrared decoy state for the roll-pitch seeker is researched.Coordinate systems which are used to describe the angles transform are defined.The LOS angles reconstruction model of the roll-pitch seeker in inertial space is established.A Kalman filter model for extracting LOS rates of the roll-pitch seeker is proposed.In this model,the target performs constant acceleration(CA)model maneuvers.The error model of LOS rates extraction under infrared decoy state is established.Several existing methods of extracting LOS rates under anti-infrared decoy state are listed in this paper.Different from the existing methods,a novel method that uses extrapolated values of target accelerations as filter measurements is proposed to solve the guidance information extraction problem under the anti-infrared decoy state.Numerical simulations are conducted to verify the effectiveness of the proposed method under different target maneuvering models such as the CA model,the CA extended model and the singer model.The simulation results show that the proposed method of extracting guidance information such as LOS rates for the rollpitch seeker under the anti-infrared decoy state is effective. 展开更多
关键词 line-of-sight(LOS)rate extraction roll-pitch seeker anti-infrared decoy Kalman filter target maneuver
下载PDF
基于WRF-SMOKE-CMAQ模型的济南市清洁取暖改造环境效益评估 被引量:1
11
作者 张怀成 白浩强 +5 位作者 许宏宇 孙晓艳 夏志勇 陈妍君 王兆军 张桂芹 《环境污染与防治》 CAS CSCD 北大核心 2023年第8期1169-1175,共7页
为评估济南市清洁取暖改造后的环境效益,以2018年为基准年,采用WRF-SMOKE-CMAQ模型模拟计算了2019—2021年济南市冬季清洁取暖改造后各项污染物改善率,并分析了不同污染时段和不同气象条件下污染物的改善率。结果表明:济南市清洁取暖改... 为评估济南市清洁取暖改造后的环境效益,以2018年为基准年,采用WRF-SMOKE-CMAQ模型模拟计算了2019—2021年济南市冬季清洁取暖改造后各项污染物改善率,并分析了不同污染时段和不同气象条件下污染物的改善率。结果表明:济南市清洁取暖改造后各污染物浓度均有不同程度的改善,其中CO、SO_(2)和细颗粒物(PM_(2.5))基准年改善率(模拟的污染物浓度相对于基准年同时段的改善率)较大,主要与散煤燃烧CO、SO_(2)和PM_(2.5)的排放因子较大有关,2020年年均改善率(模拟的污染物浓度相对于去年同时段的改善率)最大,主要与污染物的减排量最多有关;各污染物改善呈现出明显的区域差异,清洁取暖改造户数较多的区县污染物年均改善率较高;各污染物在空气严重污染时段基准年改善率均最大,重度污染时段次之,并且在不利气象条件时基准年改善率也最大,说明清洁取暖改造对冬季不利气象条件造成的高污染物浓度起到明显的削峰作用,可为济南市空气质量持续改善提供有力保障。 展开更多
关键词 WRF-smoke-CMAQ模型 清洁取暖 环境效益评估 改善率
下载PDF
Carbon Monoxide and Respiratory Disorders in Professional Female Fish Smokers at 2 Artisanal Sites in Benin
12
作者 Mênonli Adjobimey Ibrahim Mama Cissé +6 位作者 Fintani Kaki Mariano Steven Sagbohan Perside Fabien Gounongbe Rose Mikponhoue Ayélo Paul Vikkey Hinson 《Occupational Diseases and Environmental Medicine》 2023年第4期175-186,共12页
Introduction: The use of biomass for cooking is a very common practice in Africa and Benin, and is associated with exposure to organic pollutants. The aim of this study was to assess carbon monoxide exposure and respi... Introduction: The use of biomass for cooking is a very common practice in Africa and Benin, and is associated with exposure to organic pollutants. The aim of this study was to assess carbon monoxide exposure and respiratory disorders in women at artisanal fish-smoking sites. Methods: This was a cross-sectional study of women fish smokers at two artisanal fish-smoking sites in Benin. Recruitment was exhaustive. An interview using a respiratory questionnaire inspired by the Union questionnaire, spirometry and carbon monoxide (CO) measurement were carried out. Descriptive analysis and comparison of means using Student’s t-test with a threshold of p = 0.05 were performed. Results: The median age of the 81 people surveyed was 40, with an interquartile range (IQT) of [25 to 75]. The median duration of daily exposure to smoke was 6 h IQT [4, 7]. Of those surveyed, 64 (79.01%) were illiterate and 39 (48.24%) had been working for 20 years. CO levels at the start of activity varied from 89 to 145 ppm in one case and from 40 to 89 ppm in the other. Respiratory symptoms were present in 19 (23.46%);18 (22.22%) had mild airway impairment on spirometry. There was a statistically significant decrease between the mean values of peak expiratory flow (PEF), mean expiratory volume in seconds (FEV1) and forced vital capacity (FVC) before and after exposure to smoke. Conclusion: CO levels are high on fish smoking sites and respiratory problems are common. Improved working conditions are important for these women. 展开更多
关键词 Respiratory Symptoms SPIROMETRY Carbon Monoxide Fish Smoking Women
下载PDF
Design and Optimization of New Smoke Exhaust Pipe for Mining Trucks
13
作者 Qian WANG Cheng XIN +1 位作者 Jialei ZHOU Liang HAN 《Mechanical Engineering Science》 2023年第1期1-3,I0005,I0006,共5页
In order to improve the maintenance efficiency,extend the use time,ensure that the exhaust emission meets the standard,forthe 830E truck heating bucket exhaust pipe design defects,the current single smoke exhaust syst... In order to improve the maintenance efficiency,extend the use time,ensure that the exhaust emission meets the standard,forthe 830E truck heating bucket exhaust pipe design defects,the current single smoke exhaust system is transformed into atime period,convertible smoke exhaust system.After the transformation,it can not only realize the side row to prevent direct corrosion of the box bucket in summer,but also realize the heating of the box bucket at low temperature in winter to prevent snow and ice and frozen blocks from sticking to the box bucket and the materials transported.After the transformation can save a lot of manpower,material resources,financial resources,improve the service life. 展开更多
关键词 smoke exhaust pipe mining truck extended use
下载PDF
APP/ZB协效阻燃发泡木塑复合材料性能研究 被引量:1
14
作者 李奇 刘杰 +2 位作者 赵雅婷 赵雪松 雷志涛 《化工新型材料》 CAS CSCD 北大核心 2024年第1期264-269,共6页
为了拓宽发泡木塑复合材料(FWPC)的功能性,以沙柳木粉、高密度聚乙烯(PE-HD)为主要原料,纳米炭黑(Nano-CB)为导电填料,聚磷酸铵(APP)和硼酸锌(ZB)作为阻燃剂和抑烟成分进行复配,采用发泡工艺和模压法制备阻燃抗静电型发泡木塑复合材料... 为了拓宽发泡木塑复合材料(FWPC)的功能性,以沙柳木粉、高密度聚乙烯(PE-HD)为主要原料,纳米炭黑(Nano-CB)为导电填料,聚磷酸铵(APP)和硼酸锌(ZB)作为阻燃剂和抑烟成分进行复配,采用发泡工艺和模压法制备阻燃抗静电型发泡木塑复合材料。研究APP/ZB协效阻燃剂质量比对FWPC力学性能、阻燃抑烟性能及热稳定性能的影响。结果表明:当APP/ZB总加入量为20%,质量比为4∶1时,FWPC的各项性能相对较优,静曲强度、弹性模量、拉伸强度和冲击强度分别为30.11MPa、2636MPa、14.65MPa和3.72kJ/m^(2),氧指数达27.3%,属难燃级别;与单独加APP时相比,力学性能降低,烟释放速总量降低11.93%,CO产率峰值和平均CO产率分别降低80.6%和49.3%,总失重率从63.53%降至61.42%,热稳定性能提高;FWPC燃烧后炭层表面凹凸不平,复合材料的阻燃和抑烟性能得到提升。 展开更多
关键词 发泡木塑 力学性能 阻燃 抑烟 热稳定性能
下载PDF
用于加热卷烟的石蜡改性二醋酸纤维素降温滤嘴的制备与表征 被引量:1
15
作者 卢昕博 董晨晓 +5 位作者 徐建 肖卫强 徐生立 王骏 蒋健 郭杨龙 《华东理工大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期377-382,共6页
以二醋酸纤维素滤棒为载体,以食品级石蜡为相变吸热材料,采用浸渍法制备了石蜡/醋纤降温滤棒,研究了石蜡熔点和负载量对加热卷烟主流烟气温度的影响,并采用热重/差热分析仪(TG/DTA)、傅里叶变换红外光谱仪(FT-IR)、差示扫描量热仪(DSC)... 以二醋酸纤维素滤棒为载体,以食品级石蜡为相变吸热材料,采用浸渍法制备了石蜡/醋纤降温滤棒,研究了石蜡熔点和负载量对加热卷烟主流烟气温度的影响,并采用热重/差热分析仪(TG/DTA)、傅里叶变换红外光谱仪(FT-IR)、差示扫描量热仪(DSC)和场发射扫描电子显微镜(SEM)等技术对石蜡/醋纤滤棒进行了表征。石蜡/醋纤滤棒是通过醋纤滤棒的吸附作用完成复合,在抽吸过程中具有良好的热稳定性,当52~#石蜡乳化液质量分数为60%时,即石蜡负载量为35 mg时,由石蜡/醋纤滤棒组成的三段式降温滤嘴对主流烟气具有显著的降温效果,可将主流烟气温度从68℃降低到42℃。 展开更多
关键词 加热卷烟 石蜡 醋纤滤棒 降温滤嘴 主流烟气温度
下载PDF
主观规范与吸烟者戒烟行动计划:戒烟意向和关系导向特征的作用
16
作者 陈海德 张宇晗 +2 位作者 赵博强 姚静静 李伟健 《心理科学》 CSSCI CSCD 北大核心 2024年第4期973-980,共8页
考察吸烟主观规范和戒烟主观规范对戒烟行动计划的预测作用及戒烟意向的中介作用和关系导向特征的调节作用。对694名经常吸烟者进行问卷调查,结果表明:(1)吸烟者两种规范显著预测戒烟行动计划;(2)戒烟意向在两种规范与行动计划间起中介... 考察吸烟主观规范和戒烟主观规范对戒烟行动计划的预测作用及戒烟意向的中介作用和关系导向特征的调节作用。对694名经常吸烟者进行问卷调查,结果表明:(1)吸烟者两种规范显著预测戒烟行动计划;(2)戒烟意向在两种规范与行动计划间起中介作用;(3)关系导向特征正向调节吸烟主观规范和戒烟意向的关系。结果说明,吸烟者两种规范对戒烟意向及戒烟行动计划的预测作用具有共存性及拮抗性,且关系导向特征增强吸烟主观规范的预测作用。 展开更多
关键词 吸烟者 戒烟行动计划 吸烟主观规范 戒烟主观规范 戒烟意向 关系导向特征
下载PDF
排烟口朝向与挡烟垂壁对地铁站台排烟效果的影响
17
作者 钟委 吴英昊 +3 位作者 田英 梁天水 王珍珍 高子鹤 《中国安全生产科学技术》 CAS CSCD 北大核心 2024年第1期107-113,共7页
为提高地铁站台的排烟效果,采用数值模拟方法,对地铁站不同排烟口朝向的机械排烟系统排烟效果进行分析,并进一步对比挡烟垂壁高度对排烟效果影响。研究结果表明:排烟口朝向不是影响烟气控制效果的主要因素,顶面排烟的排烟效果最佳,其总... 为提高地铁站台的排烟效果,采用数值模拟方法,对地铁站不同排烟口朝向的机械排烟系统排烟效果进行分析,并进一步对比挡烟垂壁高度对排烟效果影响。研究结果表明:排烟口朝向不是影响烟气控制效果的主要因素,顶面排烟的排烟效果最佳,其总排热量是底面排烟的1.32倍,总排烟量是底面排烟的1.19倍;并通过分析3种排烟系统吸入烟气的方式和温度解释排烟效果产生差异的原因;增设挡烟垂壁可起到良好的控烟效果,当挡烟垂壁下沿高度分别降低至3.5,3.0,2.5 m时,顶面排烟,侧面排烟和底面排烟能够将烟气控制在起火防烟分区;挡烟垂壁与机械排烟系统具有协同作用,设置挡烟垂壁可以有效改善排烟效果,因此建议采用排烟管道顶面开口的排烟方式,并可通过设置一定高度的挡烟垂壁提高现有排烟系统的排烟效果。研究结果可为地铁站台排烟系统设计提供参考与借鉴。 展开更多
关键词 地铁站台 排烟口朝向 机械排烟 挡烟垂壁
下载PDF
扁平大空间船舶火灾烟气控制试验研究
18
作者 李森 王少鹏 +3 位作者 林锦 陆守香 李倩 陈国庆 《中国安全科学学报》 CAS CSCD 北大核心 2024年第5期162-167,共6页
为有效控制扁平大空间船舶火灾烟气蔓延,研究大尺度火灾过程中的油池质量损失速率、舱室温度分布、隔热效率和烟气控制效果。利用尺寸为30 m×24 m×2.3 m的模拟舱,在0.35、0.55和0.70 m等3种不同挡烟垂壁高度和机械通风条件下... 为有效控制扁平大空间船舶火灾烟气蔓延,研究大尺度火灾过程中的油池质量损失速率、舱室温度分布、隔热效率和烟气控制效果。利用尺寸为30 m×24 m×2.3 m的模拟舱,在0.35、0.55和0.70 m等3种不同挡烟垂壁高度和机械通风条件下开展试验。结果表明:挡烟垂壁高度增加,油池质量损失速率峰值减小;挡烟垂壁高度对舱室上层烟气温度的影响比对下层气体温度的影响更明显,1.4 m以上空间温度峰值明显下降,而1.4 m以下空间温度峰值无明显变化。顶棚平均温度和隔热效率随挡烟垂壁高度增加而下降。随挡烟垂壁高度增加,火源区与非火源区同时控烟模式隔热效率从28.2%提升至50.8%,火源区单独控烟模式隔热效率从29.4%提升至54.7%。 展开更多
关键词 扁平大空间 船舶火灾 烟气控制 挡烟垂壁 机械通风 控烟模式 隔热效率
下载PDF
隧道火灾相向射流排烟系统烟气质量流率比例系数 被引量:1
19
作者 王永东 任雨桐 +3 位作者 赖宜 胡志豪 史林猛 薛威 《安全与环境学报》 CAS CSCD 北大核心 2024年第3期907-913,共7页
为探究隧道相向射流排烟系统中火灾发生时烟气的流动特性,通过FDS数值模拟研究隧道内不同上、下游风速工况下的上、下游烟气质量流率变化。基于等效风速、理论分析和数值模拟结果得到上、下游风速与烟气质量流率比例系数的关系式。结果... 为探究隧道相向射流排烟系统中火灾发生时烟气的流动特性,通过FDS数值模拟研究隧道内不同上、下游风速工况下的上、下游烟气质量流率变化。基于等效风速、理论分析和数值模拟结果得到上、下游风速与烟气质量流率比例系数的关系式。结果表明:当等效风速小于临界风速时,上、下游烟气质量流率比值和烟气质量流率比例系数随等效风速增加而减小,并且等效风速与上、下游烟气质量流率比值存在线性关系;当等效风速大于临界风速时,上、下游烟气质量流率比值和烟气质量流率比例系数为0。 展开更多
关键词 安全工程 隧道火灾 相向射流排烟系统 数值模拟 烟气质量流率 比例系数 等效风速
下载PDF
2022年浙江省台州市青少年烟草流行状况及影响因素分析
20
作者 乔冬菊 王良友 +3 位作者 谢文军 柴文杰 郏超男 陈潇潇 《中国健康教育》 北大核心 2024年第9期808-815,共8页
目的 分析台州市青少年吸烟现状及影响因素,为制定青少年控烟预防策略提供科学依据。方法采用多阶段分层整群随机抽样方法,抽取台州市3个监测点,初中、普通高中和非普通高中共2927名青少年,采用自填方式填写浙江省青少年健康危险因素监... 目的 分析台州市青少年吸烟现状及影响因素,为制定青少年控烟预防策略提供科学依据。方法采用多阶段分层整群随机抽样方法,抽取台州市3个监测点,初中、普通高中和非普通高中共2927名青少年,采用自填方式填写浙江省青少年健康危险因素监测问卷。采用多因素Logistic回归分析青少年现在吸烟和二手烟暴露烟的影响因素。结果 台州市青少年吸烟率为6.12%,尝试吸烟率为25.61%,二手烟暴露率为56.17%。多因素Logistic回归结果显示,初中(OR=0.360,95%CI:0.234~0.553)、普通高中(OR=0.361,95%CI:0.223~0.585)、男性(OR=2.162,95%CI:1.478~3.162)、一起生活的人有男性吸烟(OR=6.223,95%CI:2.468~15.694)、一起生活的人有女性吸烟(OR=9.953,95%CI:1.517~65.305)、一起生活的人有男性也有女性吸烟(OR=28.875,95%CI:11.433~72.924)为青少年吸烟情况的影响因素;初中(OR=0.784,95%CI:0.623~0.985)、普通高中(OR=0.677,95%CI:0.532~0.863)、一起生活的人有男性吸烟(OR=4.626,95%CI:3.804~5.625)一起生活的人有女性吸烟(OR=3.890,95%CI:1.462~10.354)、一起生活的人有男性也有女性吸烟(OR=7.881,95%CI:5.966~10.410)为青少年吸二手烟的影响因素。结论 台州市在无烟环境创建工作上取得一定成效,但是青少年吸烟率比较高,特别是农村地区非普通高中,仍需要社会、学校和家庭共同参与控烟工作,减少青少年吸烟行为。 展开更多
关键词 吸烟 青少年 影响因素
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部