自吸过滤式呼吸器对人体主观舒适度的影响

测定了在中等（100W）和高等（155W）劳动强度下，8名受试者佩戴5种自吸过滤式呼吸器（呼吸阻力及死腔不同）从事踏车运动时的主观舒适度。结果表明：随着呼吸负荷增大，受试者的主观不适度显著增强；在中等运动负荷条件下，高温环境中人员对呼吸负荷主观不适度的反应更加明显；在高运动负荷条件下，常温环境人员对呼吸负荷主观不适度的反应更加明显。     

武安—6型防尘口罩

目前,厂矿企业广泛使用简易防尘口罩。一般简易防尘口罩的吸气和呼气均通过滤料,由于滤料受容尘及呼气水分的影响,使呼吸阻力逐渐上升。清洗后的口罩阻尘率显著下降,耐用性能也较差。为了解决简易口罩在使用中呼吸阻力上升和清洗后质量下降     

循环载荷下煤样不同方向渗透特性试验研究

针对循环采动过程中煤层不同方向渗透特征的演化规律问题，以平顶山十二矿己15煤层煤样为研究对象，利用自行研制的应力-渗流-解吸煤体变形试验装置，开展了循环围压加载下煤样不同方向渗透试验。研究结果表明:在相同的轴压、围压和平均孔隙压力下，试样平行层理面方向的渗透率大于垂直层理，平行层理面内的渗透率相差不大。在围压恒定的情况下，通过试样的流量随着渗透压差的增大而增大，且二者之间的关系可以用二次函数描述；围压增加，导致裂隙闭合，渗透率减小，当循环围压大于煤屈服强度和抗压强度时，裂隙扩展，渗透率增加；循环围压加载可以改变煤样原有不同方向渗透率大小顺序，渗透率与原初始渗透率比值随循环加载次数的增加而增大。     

泄爆面特征参数对天然气爆炸超压峰值的影响规律

为揭示泄爆面特征参数对大尺度受限空间内天然气爆炸超压峰值结构的影响机制，基于典型房间特征，借助计算流体动力学技术研究不同泄爆面开启压力、开启时间以及泄压比等参数条件下室内天然气泄爆超压峰值结构的分布规律。研究结果表明:峰值Pb随开启压力和开启时间增加均呈线性增长趋势，而泄压比对Pb影响较小；峰值Pmfa与室内最大火焰面积有关，随开启压力、开启时间的增加和泄压比的减小，气体出流速度增大，进而产生更强的湍流，导致室内火焰面积和气体燃烧率增加，最终Pmfa增大；峰值Pext随泄压比增加呈快速降低趋势，同时开启压力和开启时间对Pext影响具有协同效应，共同促进Pext快速增加。     

不同劳动强度下人体呼吸参数变化实验研究

人体呼吸参数对呼吸防护装备内部微环境的稳定性至关重要，为获得不同劳动强度下人体呼吸参数及变化规律，以相对心率指数表征劳动强度等级并设计构建呼吸参数采集系统。通过开展多人次不同劳动强度呼吸实验，记录实时瞬时心率、呼吸压力、呼吸频率数据并采集呼出气样本，进行气相色谱分析。研究结果表明:相对心率指数能够消除劳动强度表征中的个体差异及劳动形式差异，对劳动强度具有良好表征作用；呼吸压力及频率随劳动强度增加呈现增强和变大的趋势；心率及呼吸压力信号的样本熵显示，心率稳定性随劳动强度的增加而降低，呼吸模式稳定性则增强；呼出气中O2含量随劳动强度增加而降低，CO2与H2O含量呈现增长趋势，绝对变化量及变化比例随劳动强度不同呈现明显差异。     

不同冲击速度下硬煤的力学特性试验研究

为了研究硬煤破坏过程中的动态力学特性，采用Φ50 mm变截面分离式霍普金森压杆（SHPB）试验系统，对45#钢制薄壁套筒施加环向约束的硬煤试件进行不同加载速率的冲击压缩试验，得到被动围压下轴向应力-应变曲线、径向应力-应变曲线及最大被动围压和冲击速度的关系。研究结果表明:峰值应力、峰值应变随着冲击速度的增大而增大，最大被动围压值与冲击速度呈幂次增长的关系；被动围压下的硬煤试件变形受到限制，试件延性、抗压能力显著提高；随着冲击速度的增大，薄壁套筒对试件的约束也逐渐增大，达到峰值后，冲击速度对被动围压的影响减小，筒壁厚度影响着被动围压效果。     

自吸过滤式全面罩呼吸阻力检测方式探讨

简要介绍了自吸过滤式呼吸防护用品的种类和全面罩的基本结构.重点描述了日本社团法人产业安全技术协会和我国国家标准中规定的自吸过滤式全面罩呼吸阻力的检测原理、检测程序和检测方式,用两种检测方式分别对DR165LAN型全面罩和X- Plore 5500全面罩的呼吸阻力进行测试,对测试结果进行比较,通过分析与讨论,建议检测自吸过滤式全面罩呼吸阻力时,应采用将全面罩的外面罩和内面罩拆开分别测试的方式,阻力值加和,进而得出贴近自吸过滤式全面罩在实际使用时呼气和吸气阻力的值.     

呼吸防护用品与灾后呼吸道疾病的预防

在抗震救灾中，呼吸防护用品与灾后呼吸道疾病的预防紧密相关。当抗震救灾工作进入第二个阶段时，正值夏季灾区天气更加湿热，大量人群不得不集中生活，相互之间接触频繁，废墟无法及时清除，极有利于蚊蝇滋生；目前处于麻疹和风疹高发期，在灾区这样的特殊环境条件下，灾后防疫无疑是面临的艰巨任务。卫生部门派出的国家和有关省（市、区）卫生防疫队都抵达灾区，     

降低防毒面具吸气阻力研究

呼吸阻力是防毒面具的一个重要性能指标，直接关系到面具使用的舒适性。在保证整体防护水平的同时，研究降低呼吸阻力，尤其是吸气阻力，是减轻从业人员佩带防毒面具生理负担的一个关键措施。     

十种放松方式

快节奏的工作生活给人们的精神带来了不少的压力。下面１０种放松法可以帮助你减轻精神压力，使自己身心放松。 打盹。学会在一切场合，如家中、办公室、走廊、甚至汽车里打吨，只需１０分钟就会使你精神振奋。 想象。通过想象一个你所喜爱的地方，把思绪集中在所想象东西的“看、闻、听”上，并逐渐入境，由此达到精神放松。 按摩。紧闭双眼，用自己的手指尖用力地按摩前额和后脖颈处，有规则地向同一方向旋转。 呼吸。进行浅呼吸，慢慢吸气、屏气，然后呼气，每阶段持续８拍。 腹部呼吸。平躺在地板上，身体自然放松，紧闭双眼。呼气，腹…     

Heart rate variability and motion sickness during forklift simulator driving

The goal of the study was to determine the effect of a 1-h hour long forklift truck virtual simulator driving on the mechanism of autonomic heart rate (HR) regulation in operators. The participants were divided into 2 subgroups: subjects with no definite inclination to motion sickness (group A) and subjects with a definite inclination to motion sickness (group B). Holter monitoring of electrocardiogram (ECG) signal was carried out in all subjects during the virtual simulator driving. For 12 consecutive epochs of ECG signal, HR variability analysis was conducted in time and frequency domains. In subjects with a definite inclination to motion sickness after ~30 min of the driving, changes in parameter values were found indicating an increase in sympathetic and parasympathetic activity with parasympathetic dominance.     

Research on simultaneous impact of hand-arm and whole-body vibration

This article presents the results of laboratory tests on the combined effect of whole-body vibration (WBV) and hand-arm vibration (HAV). The reactions of subjects exposed to various combinations of vibration were recorded. The vibrotactile perception threshold (VPT) test identified changes caused by exposure to vibration. Ten male subjects met the criteria of the study. There were 4 series of tests: a reference test and tests after exposure to HAV, WBV, and after simultaneous exposure to HAV and WBV. An analysis of the results (6000 ascending and descending VPTs) showed that the changes in VPTs were greatest after simultaneous exposure to both kinds of vibration. The increase in VPT, for all stimulus frequencies, was then higher than after exposure to HAV or WBV only.     

Control chart for monitoring occupational asthma

INTRODUCTION: Work-related asthma has become the most prevalent occupational respiratory disease in the developed world. Occupational asthma is thought to affect 5%-10% of people worldwide. The first step in the diagnosis of occupational asthma is to establish work-relatedness. Although considerable research has been conducted in the area of occupational asthma, no simple, effective, and statistically sound method has been developed that can be used as an initial step to effectively identify the workers at risk for occupational asthma. The purpose of this research was to investigate whether Shewhart control chart method can be used as an effective method to detect occupational asthma. METHOD: Forty-five workers who completed the study and provided usable peak expiratory flow (a lung function marker) recordings while at work and away from work were included in this study. Control charts were developed using Shewhart's Method. The lower control limit of at work control chart (LCL(W)) was compared to each subject's Personal Best (PB) value. RESULTS: Reviewing the results of this comparison showed LCL(W)<60% PB to have a sensitivity of 85.71%, specificity of 87.50%, and an error rate of 13.33%. When the subjects suspected for false positive and false negative diagnoses were identified, the test produced a sensitivity of 95.24%, a specificity of 95.83% and an error rate of 4.44%. CONCLUSIONS: Our results were as good as, and in some cases better than, published clinical guidelines. IMPACT ON INDUSTRY: Our research showed that the control chart method is an effective, simple, and inexpensive tool for early intervention in workers suspected for occupational asthma.     

Marijuana-, alcohol-, and drug-impaired driving among emerging adults: Changes from high school to one-year post-high school

IntroductionDriving while impaired (DWI) increases the risk of a motor vehicle crash by impairing performance. Few studies have examined the prevalence and predictors of marijuana, alcohol, and drug-specific DWI among emerging adults.MethodsThe data from wave 3 (W3, high school seniors, 2012, N = 2407) and wave 4 (W4, one year after high school, N = 2178) of the NEXT Generation Health Study with a nationally representative cohort. W4 DWI (≥ 1 day of past 30 days) was specified for alcohol-specific, marijuana-specific, alcohol/marijuana-combined, illicit drug-related DWI. Multinomial logistic regression models estimated the association of W4 DWI with W3 covariates (perceived peer/parent influence, drinking/binge drinking, marijuana/illicit drug use), and W4 environmental status variables (work/school/residence) adjusting for W3 overall DWI, demographic, and complex survey variables.ResultsOverall DWI prevalence from W3 to W4 changed slightly (14% to 15%). W4 DWI consisted of 4.34% drinking-specific, 5.02% marijuana-specific, 2.41% drinking/marijuana combined, and 3.37% illicit drug-related DWI. W3 DWI was significantly associated with W4 alcohol-related and alcohol/marijuana-combined DWI, but not other DWI. W3 marijuana use, binge drinking, and illicit drug use were positively associated with W4 marijuana-specific, alcohol/marijuana-combined, and illicit drug-related DWI, respectively. W3 friend drunkenness and marijuana use were positively associated with W4 alcohol-specific and marijuana-related DWI, respectively. W3 peer marijuana use was negatively associated with W4 alcohol-specific DWI.ConclusionsDriving under the influence of alcohol, marijuana, and illicit drugs is a persistent, threatening public health concern among emerging U.S. adults. High school seniors' binge drinking as well as regular alcohol drinking and marijuana/illicit drug use were independently associated with respective DWI one year after high school. Peer drunkenness and marijuana use in high school may be related to subsequent DWI of emerging adults.Practical applicationsThe results support the use of injunctive peer norms about getting drunk and smoking marijuana in guiding the development of prevention programs to reduce youth DWI.     

基于模拟飞行任务下的眼动指标分析

分析眼动指标在定量测量飞机驾驶员的注意力分配规律和工作负荷变化中的作用。让4个被试者在飞行模拟器上完成了3个不同阶段的模拟飞行任务,同时用眼动仪器记录了注视、扫视、瞳孔尺寸方面的眼动指标,划分为座舱外景和内部仪表两个兴趣区域对数据进行了对比和认知分析。被试者在外景有更多的注视点、更多和更长的注视时间,在仪表上的平均瞳孔尺寸比外部视景要大,平均扫视幅度随任务难度增大而减小。眼动指标可以客观地反映驾驶员的注意力分配规律和工作负荷变化;视觉飞行规则下,飞行员主要从外景获取视觉信息,他的大部分注意力都集中在外景。     

Clogging of Filtering Material Systems Used for Disposable Respirators

The article shows the problem of clogging in connection with the parameters of filtering materials used in respiratory protective equipment. The results of investigations of airflow resistance changes during the depositing of dust inside the filtering material are presented. The configuration of layers differing in mass per unit area and the number of layers, were taken into consideration. For each configuration, the clogging abilities and the changes of airflow resistance as a reason of loading with dust were assessed. The analysis of tested materials confirms the hypothesis that there is an important coincidence between the properties of the material used in filtering equipment and the clogging coefficient. The results show that the filter should have a layered structure and that the outer layer should be made of a nonwoven of relatively high surface density.     

Prevalence of work-family conflict: Are work and family boundaries asymmetrically permeable?

This study tested Pleck's (1977) hypothesis concerning gender differences in the relative permeability of work and family boundaries. Data were obtained from a randomly drawn community sample of 631 employed adults (278 men; 353 women). Respondents reported that work interfered with family life (W→F conflict) more frequently than family life interfered with work (F→W conflict). These results suggest that work and family boundaries are indeed asymmetrically permeable with family boundaries being more permeable than work boundaries. However, there was no evidence of gender differences in the pattern of asymmetry, indicating that the dynamics of work and family boundaries may operate similarly among men and women. Implications for future research are discussed.     

不同外热功率下18650锂离子电池热失控特性*

为探究不同外热功率（220,170,120,70 W）下锂离子电池的热失控特性,采用动压变温实验舱作为燃爆实验舱,并利用量热仪和ISO-9705烟气分析仪监测特征参数,对荷电状态（SOC）为100%的18650型锂离子电池进行高温热失控实验。结果表明:在不同的外热功率条件下,锂离子电池进入热失控的过程呈现出相似的趋势,但是各阶段的特性却存在差异。池体表面中心温度、HRR,THR和耗氧量均随外热功率的降低而降低。高外热功率下燃爆响应时间点明显提前,池体温度更高,220 W外热功率下,燃爆响时间点为176 s,池体温度为720.6 ℃,比70 W时提前366 s,高210.03 ℃,可见高外热功率时,电池热危害性更高。热解烟气CO的峰值体积百分比浓度随着外热功率的降低而升高,而CxHy的峰值质量百分比浓度降低,,CO2的峰值体积百分比浓度降低。在70 W外热功率时,CO峰值体积百分比浓度高达0.322%,220 W时CO峰值体积百分比浓度仅为0.165%,说明低外热功率时,电池毒危害性更高。