20种护耳器噪声防护效果的探讨

探讨了国内外２０种护耳器对石油钻井噪声的防护效果。首先在隔声室内模拟石油钻井工人接触的噪声环境，声级达１０３ｄＢ（Ａ）。采用护耳器主观测量方法对每种护耳器进行噪声防护效果测量，并筛选出噪声防护效果明显的几种护耳器。     

护耳器使用现状评述

研究表明：护耳器现场使用实际声衰减值低于实验室值,其原因是护耳器的实验室测量条件较为严格。工人在现场实际使用护耳器时,未能同实验室中的受试者一样佩戴护耳器,因而获得的护耳器声衰减比实验室所测得的值低。另一方面,在８小时强噪声环境中工作期间,未自始至终佩戴护耳器,则也达不到预期的保护听力的效果。笔者还综合分析和评述了护耳器现场使用时实际声衰减值降低的原因,并提出了一些有益的建议     

家用电器防触电不可忽视的两个技术措施——接地(或接零)和便用漏电保护器

本文从技术角度阐述了安全使用家用电器防触电的类型,提出了家用电器防止触电避免安全事故发生的具体技术措施。     

浅析防雷中存在的问题

通过分析防雷中存在的认识误区,提出防雷是一个综合性、系统性工程,防雷的防护原则是全方位防护、综合治理、层层设防.只有根据防雷的实际要求,将接闪、传导、分流、接地、屏蔽、等电位连接等技术措施合理实施,才能构成一个系统、有效的防雷系统.     

Signal Recognition and Hearing Protectors With Normal and Impaired Hearing

Recognition of acoustic signals when perception is subject to interference from noise has already been extensively studied. In this study the influence of hearing protectors (HP) (plugs, muffs) and hearing loss on signal recognition is examined. Different spectrums and levels of the noise are also included. The test results are shown as the masked threshold for the signals heard and identified. In the case of normally hearing subjects a frequency-independent HP (plug) improves hearing performance, while frequency-dependent HP (muffs) tends to worsen it, especially with low-frequency noise. Hearing losses even worsen hearing performance when plugs are worn. Design suggestions are made to optimise signal recognition. Minimum signal-to-noise ratio and the use of HP are discussed.     

石油钻井工人护耳器防护效果的评价

从实验室筛选出的７种护耳器，经９９名钻井工人现场使用作了主观评价。通过现场工人噪声防护效果的评价，推选出４种护耳器作为石油勘探工人首先使用的个人防护用品。     

化工企业防雷保护设计探讨

介绍了雷击的形式及特点、雷击电磁脉冲（LEMP）的防护设计以及储罐、工艺装置防雷设计。     

Effect of wearing hearing protectors on the audibility of railway warning signals – an experimental study

The effect of wearing hearing protectors on the audibility of warning signals has been evaluated for three specific railway-related jobs: track workers, train drivers and platform agents. Masked thresholds were measured in the laboratory, on railway agents with normal hearing, using warning signals and background noises typical of each job. Out of the 36 situations tested in total, statistical analyses showed that wearing earplugs improves the perception in 11 situations, deteriorates the perception in 10 situations and has no significant effect in 15 situations (as compared to no hearing protector). The deteriorations essentially concern signals which have no (or not enough) energy in the low-frequency range (ff相似文献   

砷污染防治与含砷木材防腐剂的开发应用

综述了有色工金属工业的砷污染以及砷资源的综合利用。砷品订用于木材防腐和防治白蚁。大力发展木材防腐剂对消除砷害和保护生态环境都具有重大意义以及巨大的社会和经济效益。     

石化系统电子设备的雷电过电压保护

结合国际、国内有关防雷标准,介绍了石化系统电子设备的雷电过电压保护的必要性和雷电过电压保护系统.石化系统电子设备防雷是一系统工程,必须将直击雷防护、等电位连接和系统地安装电涌保护器有机地结合起来,对于电涌保护器,不但要选择好适当的型号,还要注意其安装的位置和彼此配合的层次.