机械行业工人肌肉骨骼损伤的调查

选择机械行业８７９名工人作为观察组,另选年龄、性别、工龄相近的９４６名行政管理人员作为对照组,通过询问调查及体验,观察组人员肌肉骨骼损伤的检出率显著高于对照组（Ｐ０．０１）,且随着工龄延长而升高。体验的各种指标阳性率显著高于对照组（Ｐ０．０１）。患有肌肉骨骼损伤的观察组工人中有９０．３％的人认为长期固定的作业姿势是造成肌肉骨骼损伤的原因。提示：长时间固定的作业姿势是肌肉骨骼损伤的一个危险因素。     

非稳态噪声对作业工人听力的影响

1引言 长期接触高噪声可以引起听力损伤,且研究证实稳态噪声累积暴露量与听力损伤患病率之间存在剂量-反应关系[1].轧钢作业岗位噪声声压级变化较大,检测发现其含有脉冲噪声成分.本研究通过对轧钢作业现场噪声的测试和作业工人听力的检测,观察轧钢作业噪声对作业工人听力的影响,并按等能量原理,用累积噪声暴露量(Cumulative noise exposure,CNE)[2]进行分层分析,以评价轧钢作业非稳态噪声暴露与听力损伤的关系.     

矿用人员定位安全管理系统构建

乌兰木伦KJJ133矿用人员安全管理系统包括:KGE型矿用人员定位射频卡、KJF82型矿用人员定位分站、KGE41型矿用射频定位器。该系统可以建立一个完整、灵活和实时的井下人员管理系统,包括井下作业工人的计划安排、工人进出巷道的权限管理、巷道人员分布、作业工人个人资料、车辆管理等进行管理,来实现井下管理信息化,同时提高矿井开采生产管理和作业安全的水平。     

纺织厂挡车工三班工效调查

为了解轮转作业对工人健康和工效的影响，文章作者随机抽取６２名轮班作业纺织女工进行了调查。各班次间自身比较结果表明：夜班次品率增加，５ｍｉｎ打结速度降低；夜班后工人疲劳症状增多。提示轮班作业对工人健康和工效均有一定影响。     

煤矿采煤生产中的防尘管理与技术措施

煤炭企业在生产作业过程中,会产生大量的煤尘,在此环境下,作业工人长期接触煤尘,会引起尘肺、煤肺等职业病。笔者就煤矿采煤生产中的防尘管理与技术措施提出了自己的见解。     

电子行业肌肉骨骼损伤的调查

对２１４１名电子行业坐位作业工人及２４８６名对照组人员的颈、肩、腕和下背肌肉骨骼损伤情况进行了流行病学调查，同时对工人的工作环境及工作场所人机界面进行了调查。结果表明：观察组人员颈、肩、下背、手及腕部肌肉骨骼损伤的患病率明显高于对照组（Ｐ＜０．０１）。且患病率均随工龄延长而升高，观察组高于对照组（Ｐ＜０．０１）。体征检查结果，观察组的颈部活动受限，颈部压痛、颈突轴位挤压试验、肩部活动受限、肩部压痛、Ｔｈｏｍａｓ征及Ｔｉｎｅｌ’ｓ征等项指标阳性率均高于对照组（Ｐ＜０．０１）。患病人群病因构成显示，与工作有关的占病因第１位。因此认为不良的作业坐姿、工龄及重复用力是肌肉骨骼疾患的重要危险因素。     

吸氧:长春“一汽”劳保新享受

<正>据《安全生产报》报道,吉林长春第一汽车集团公司热处理厂六车间,建立了一座职工吸氧间。“一汽”热处理厂一线工人,在生产中大量接触一氧化碳和多种有毒有害气体,严重影响职工健康。1993年,公司职工医院职业病科对这个厂202名热处理工种工人和110名电镀及其他工种工人进行体检,发现热处理工中有54人心电有改变,6人肺部不正常,大部分电镀工有鼻前庭糜烂现象。为此公司安全处决定出     

苯气体检测报警器示值误差测得值的不确定度评定

苯气体检测报警器主要用于检测作业场所等环境中的苯气体,对人的安全有重要影响。本文对苯气体检测报警器示值误差测得值的不确定度评定与表示,以便检测人员可以正确的使用测得值。     

接触低浓度一氧化碳工人行为功能改变

文章选择接触一氧化碳（ＣＯ）工人６１人为观察组（另选５６人作为对照组）进行了ＷＨＯ推荐的神经行为核心测试组合（ＷＨＯ－ＮＣＴＢ）研究。结果表明：接触组在情感状态、简单反应时、数字跨度、手工敏捷度、数字译码和视觉保留等项目的标准得分显著低于对照组（Ｐ＜０．０５），并且在简单反应时和手工敏捷度两项指标上存在剂量－反应关系。提示长期反复接触ＣＯ可对中枢视觉系统功能状态产生不良改变。     

煤矿工人冒险行为外显影响因素分析

研究发现：影响煤矿工人冒险行为的外显因素主要有三大类，即个体特点表现、组织管理状况及生产环境条件等；不同背景煤矿工人对其冒险行为外显影响因素的评价基本上是一致的。但是，文化水平高的工人对事故隐患更敏感、更警惕；长期的井下作业会使工人表现出较多的消极性性格特点；年长的工人普遍认为工作条件差；全民合同工与固定工及临时工相比，更不满意于现有的工作；事故组工人与非事故组工人相比，更加感到工作状况不理想、单调、乏味，并且在工作中易冲动、理解力不好等；婚姻状况不同对各因素的认知基本上没有影响；领导和工人对组织绩效的期望及事故隐患的认知不一致     

碳前驱体热解机理的量子化学理论研究几何结构、反应焓变、化学键和热反应活性

运用Gaussian98程序包中半经验的量子化学(AM1)方法,对间二甲苯系列化合物(苯环上引入不同取代基-OH、-SH、-CN时的化合物)的热裂解机理进行了研究,对设定的8种有自由基形成的热裂解过程中的反应物、产物的全优化几何构型和反应的热力学量的计算结果表明无论苯环上联接的是吸电子基团还是供电子基团,这些化合物的热裂解键,都是首先从苯环上甲基碳氢键开始,也就是说甲基碳氢键是这类化合物最易断裂的键,也是热裂解的最初反应过程,该结论与实验结果一致;间二甲苯上若联有供电子取代基(-OH,-SH),反应物的热反应活性将增大,若联有吸电子取代基(-CN),反应物的热反应活性将减小。间二甲苯系列化合物的热反应活性的顺序为d1＞d2＞a＞d3。     

An analysis of synergistic and antagonistic behavior during BTEX removal in batch system using response surface methodology

The removal of benzene, toluene, ethylbenzene and xylene (BTEX) as quaternary mixtures were studied in batch systems using a well-defined mixed microbial culture. The synergistic and antagonistic effects of total BTEX removal (BTEXT-RE) due to the presence of mixed substrate was evaluated through experiments designed by response surface methodology (RSM). The low and high concentrations of individual BTEX were 15 and 75 mg l(-1), respectively. The results showed that, increasing the concentration of xylene increased the cumulative BTEX removal (BTEXT-RE), however the reverse occurred when benzene concentrations were increased from low to high levels. A mixed response of increasing and decreasing trend in the BTEXT-RE value was observed when either of toluene or ethylbenzene concentration was increased. When the concentrations of individual BTEX compounds were 30 mg l(-1), the BTEXT-RE was about 58%. Complete BTEXT-RE was achieved at optimal BTEX concentrations of 48.1, 45.6, 49.3 and 56.6 mg l(-1). The RSM approach was found efficient in explaining the main, squared and interaction effects among individual BTEX concentrations on the BTEXT-RE in a more statistically meaningful way.     

Simulating Retention in Gas–Liquid Chromatography: Benzene, Toluene, and Xylene Solutes

Accurate predictions of retention times, retention indices, and partition constants are a long sought-after goal for theoretical studies in chromatography. Although advances in computational chemistry have improved our understanding of molecular interactions, little attention has been focused on chromatography, let alone calculations of retention properties. Configurational-bias Monte Carlo simulations in the isobaric–isothermal Gibbs ensemble were used to investigate the partitioning of benzene, toluene, and the three xylene isomers between a squalane liquid phase and a helium vapor phase. The united-atom representation of the TraPPE (transferable potentials for phase equilibria) force field was used for all solutes and squalane. The Gibbs free energies of transfer and Kovats retention indices of the solutes were calculated directly from the partition constants (which were averaged over several independent simulations). While the calculated Kovats indices of benzene and toluene at T=403 K are significantly higher than their experimental counterparts, much better agreement is found for the xylene isomers at T=365 K.     

Performance of BTX degraders under substrate versatility conditions

A microbial consortium acclimatized with benzene, toluene or xylene (BTX) was employed to study the degradation pattern of these compounds individually under aerobic conditions. Batch and continuous experiments were conducted to evaluate the adaptability of the enriched cultures under substrate versatility conditions. The bio-kinetic parameters obtained under substrate versatility conditions were compared with those of a single substrate condition. Similar degradation patterns were observed for all the substrates with inhibition occurring at higher concentration (approximately 150 mg/L for benzene and xylene, and approximately 200 mg/L for toluene). Toluene degradation was highest, followed by benzene and xylene in the aqueous phase. Adaptation to a more toxic compound like benzene and xylene improved the utilization of toluene. On the other hand, microbes grown on a less toxic compound (toluene) grew at a lower rate in the presence of more toxic compounds. Suitable kinetic parameters such as micro(max) (maximum specific growth rate per hour), Ks (half saturation constant, mg/L), and KI (threshold substrate inhibition constant, mg/L) were determined using Haldane and Levenspiel substrate inhibition models. The Haldane equation seems to be an adequate expression for the system. The degradation behavior of pollutants in the gas phase was also evaluated using a toluene acclimatized biotrickling filter operated in continuous mode. The biotrickling filter acclimatized with toluene could degrade benzene and xylene with a lower elimination capacity. But, the system could recover its original efficiency quite fast even after a prolonged shock loading. The degradation was better for toluene, followed by benzene and xylene.     

Effect of hydrometallurgical process parameters on the Mn2O3 nano catalysts derived from spent batteries used in the plasma catalytic oxidation of BTX

Manganese oxide catalysts have been synthesized from the used batteries via hydrometallurgical method and effect of hydrometallurgical parameters such as the effect of acid type (H₂SO₄, HNO₃, HCl), acid concentration (0.5, 1, 1.5, 2 %v/v) and powder to acid ratio (1/50, 1/60, 1/70, 1/80) were in detail investigated. The physico-chemical properties of as-prepared catalysts were characterized by FT-IR, XRD, FESEM, EDX, BET, TEM, and TPR-H₂ analysis. The activity of as-prepared catalysts were investigated towards the oxidation of benzene, toluene, and xylene (BTX) in a plasma-catalytic process. The results show that benzene and toluene conversion were almost constant in the range of 97–98% in case of various acid types, acid concentrations and solid to liquid ratios. However, the xylene conversion were varied in case of different hydrometallurgical factors. The highest xylene conversion was obtained in the presence of MnS0.5–60, which was prepared using H₂SO₄ with concentration of 0.5%v/v and solid to liquid ratio of 1/60. The effect of the input voltage and BTX flow rate on the BTX conversion was also investigated using MnS0.5–60 catalyst in detail.     

Simultaneous quantitative determination of benzene, toluene, and xylenes in water using mid-infrared evanescent field spectroscopy

Attenuated total reflection mid-infrared spectroscopy is applied for simultaneous detection and quantification of the environmentally relevant analytes benzene, toluene, and the three xylene isomers. The analytes are enriched into a thin polymer membrane coated onto the surface of an internal reflection waveguide, which is exposed to the aqueous sample. Direct detection of analytes permeating into the polymer coating is performed by utilizing evanescent field spectroscopy in the fingerprint range (>10 microm) of the mid-infrared (MIR) spectrum (3-20 microm) without additional sample preparation. All investigated compounds are characterized by well-separated absorption features in the evaluated wavelength regime. Hence, data evaluation was performed by integration of the respective absorption peaks. Limits of detection lower than 20 ppb (v/v) for all xylene isomers, 45 ppb (v/v) for benzene, and 80 ppb (v/v) for toluene have been achieved. The straightforward experimental setup and the achieved detection limits for these environmentally relevant volatile organic compounds in the low-ppb concentration range reveal a substantial potential of MIR evanescent field sensing devices for on-line in situ environmental analysis.     

Organic solvents permeation through protective nitrile gloves

Effective diffusion coefficients for the permeation of several organic solvents through nitrile gloves were experimentally investigated using the American Society for Testing and Materials (ASTM) F-739 test cell method. Fick's effective diffusion coefficients for benzene, toluene, ethyl benzene, xylene, and styrene were estimated to be 0.61+/-0.02, 0.50+/-0.06, 0.27+/-0.02, 0.31+/-0.03, and 0.21+/-0.03 (x10(-6)cm(2)/s), respectively. These results were comparable to results found by others using different permeation models. Using a transient mass diffusion equation and appropriate initial and boundary conditions, the effective diffusion coefficients were found to adequately simulate the concentration profiles of the organic solvents in the collection chamber during the permeation test. The effective diffusion coefficients were found to be inversely correlated to the molecular weight of the compounds. The results of this study can be used to estimate the exposure to workers using nitrile gloves.     

无水AlCl_3作用下EPDM的交联与接枝性能

以无水AlCl3为催化剂,在溶液体系考察了温度、催化剂用量、溶剂品种等因素对乙丙三元橡胶(EPDM)交联与接枝性能的影响。结果显示,无水AlCl3可以引发EPDM间产生交联反应;温度较低时,EPDM交联反应困难,但乙丙三元橡胶与聚苯乙烯(PS)间产生了接枝反应;在苯与二甲苯溶剂中不易形成活性正碳离子;催化剂用量增大,凝胶含量与交联密度增大;PS进入EPDM凝胶网络,使PS相热稳定性提高,玻璃化温度提高。     

Volatile organic compound constituents from an integrated iron and steel facility

This study measured the volatile organic compound (VOC) constituents of four processes in an integrated iron and steel industry; cokemaking, sintering, hot forming, and cold forming. Toluene, 1,2,4-trimethylbenzene, isopentane, m,p-xylene, 1-butene, ethylbenzene, and benzene were the predominant VOC species in these processes. However, some of the chlorinated compounds were high (hundreds ppbv), i.e., trichloroethylene in all four processes, carbon tetrachloride in the hot forming process, chlorobenzene in the cold forming process, and bromomethane in the sintering process. In the sintering process, the emission factors of toluene, benzene, xylene, isopentane, 1,2,4-trimethylbenzene, and ethylbenzene were over 9 g/tonne-product. In the vicinity of the manufacturing plant, toluene, isopentane, 1,2,4-trimethylbenzene, xylene and ethylbenzene were high. Toluene, 1,2,4-trimethylbenzene, xylene, 1-butene and isopentane were the major ozone formation species. Aromatic compounds were the predominant VOC groups, constituting 45-70% of the VOC concentration and contributing >70% to the high ozone formation potential in the stack exhaust and workplace air. The sequence of VOC concentration and ozone formation potential was as follows: cold forming>sintering>hot forming>cokemaking. For the workplace air, cokemaking was the highest producer, which was attributed to the fugitive emissions of the coke oven and working process release.     

气相色谱法测定空气中苯系物的热解吸和溶剂解吸比对研究

针对测定工作场所空气中苯系物的标准方法热解吸和溶剂解吸．气相色谱法在实际应用中存在的问题，分别考察和比对了这两种方法，特别对影响热解吸效率的因素进行了详细研究，发现改善热解吸方式能提高活性炭管的合格率和热解吸效率；不同温度下需要的解吸时间不同，延长热解吸时间有利于提高样品解吸率；并对标准方法GBZ／T160．42-2004提出了相应的改进措施。