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991.
此文分析了传统方法建立标准件库的缺陷与存在的问题,提出了用作者开发的专用信息描述语言描述几何构形信息的思路。并介绍了基于信息描述语言建立标准件库和资源库的途径。  相似文献   
992.
结合河北省桃园农药厂开发的百草枯新工艺(低温钠法),对百草枯生产过程中的环境风险进行评价。首先介绍了百草枯生产的工艺流程,然后系统分析了金属钠、吡啶、氯甲烷以及百草枯等危险物的性质及其危害性,并在上述分析的基础上,采用相应的评价模型对钠化釜及合成釜中吡啶可能造成的爆炸与扩散进行了评价。最后,就百草枯生产的环境风险提出了相应的对策和防范措施。  相似文献   
993.
For over 16 years, Conservation Biology has been the voice of our global community of conservation biologists. Now, the Society of Conservation Biology and the Editorial Office of Conservation Biology need to hear YOUR voice!
To make the journal as relevant as possible, we invite you to participate in an anonymous online survey for our Conservation Biology readers, authors and reviewers. This survey is the first of its kind for Conservation Biology — your feedback is extremely valuable!
To participate, simply go to www.conservationbiology.org/journalsurvey
We hope to hear from you soon!
Society for Conservation BiologyThe Editorial Office of Conservation Biology  相似文献   
994.
论述了机械设备壳体化学清洗的除油、除锈、中和、钝化所用的配方、工艺方法及使用注意事项;机械表面除漆的工艺和配方;机械零部件的化学清洗和电化学清洗的配方、工艺条件和使用方法。  相似文献   
995.
水土资源是人类生存与发展的重要物质,是进行农业生产的基本条件。文章针对我国山地、丘陵面积较大、地质条件复杂、人为破坏加速、水土流失严重的实际,分析了因人类自身的破坏造成土壤侵蚀的一系列问题,论述了因水土流失危胁生存环境、造成土地质退、降低土壤肥力、淤积湖库和湖泊、制约粮食生产、影响城市安全、干扰能源基地建设等严重危害国民经济发展和人民生活的提高的问题。  相似文献   
996.
个体防护装备国家标准作为国家标准的一个重要组成部分.其制修订工作除了要符合国家的各项规定外,还有其特殊性。现就其具体的工作流程,进行详细的介绍,供个体防护装备科研单位和企业参考。  相似文献   
997.
建立并扼要讨论了,碳钢在任意等温温度下的时间一成分状态图及其应用,将这种由平衡或不平衡组织构成的状态图定义为;碳钢的等温动态相图  相似文献   
998.
介绍了高级氧化技术的发展及其特点,并综述了化学氧化、光催化氧化、水热氧化以及高压脉冲放电等离子体、超声等高级氧化技术及其在水处理中的应用。随着对高级氧化技术不断深入的研究,其在水处理领域的应用将更加成熟并且越来越广泛。  相似文献   
999.
我国火电厂烟气脱硫行业2004年发展报告   总被引:1,自引:0,他引:1  
本文介绍了2004年我国火电厂烟气脱硫行业的发展情况及存在的主要问题,并对行业发展做了预测。  相似文献   
1000.
Abstracts     
Cancer mortality of art glass workers in Tuscany, Italy. R. Pirastu, D. Bartoli, G. Battista, M. DeSantis, T. Iaia, D. Orsi, M. Tarchi, M. Valiani. Scand J Work Environ Health, 24(5): 386-391.Objectives: This study considers the cause-specific mortality from cancer among art glass workers employed in 17 industrial facilities in Tuscany, Italy.Methods: A cohort of 3390 workers, 3180 men and 210 women, employed at least 1 year, was taken from December 1993. The cause-specific expected mortality from cancer was computed for men relative to Tuscany rates, specified for gender, 5-year age groups, and calendar year. Separate analyses were carried out for the job title of maker and former and for batch mixers.Results: For 3180 men, the observed mortality was above the expected for larynx [standardized mortality ratio (SMR) 166, 90% confidence interval (90% CI) 90 —282], lung (SMR 123, 90% CI 100—151), stomach (SMR 105, 90% CI 76 —142), and brain (SMR 150, 90% CI 71—282) cancer. Increases for these causes were also found for the makers and formers. Mortality from larynx and lung cancer increased with latency, and significantly increased SMR values were observed for ≥21 years since first exposure. The increasing pattern was also present after adjustment for smoking.Conclusions: The results showed consistently increased mortality from larynx and lung cancer in the overall cohort and among makers and formers. Stomach and brain cancer was also increased in the overall cohort and among the makers and formers.Occupational skin and respiratory diseases among hairdressers. T. Leino, L. Tammilehto, M. Hytönen, E. Sala, H. Paakkulainen, L. Kanerva. Scand J Work Environ Health, Vol. 24, No. 5, 398-406.Objectives: The occurrrence and causes of hairdressers' occupational skin and respiratory diseases were studied.Methods: Of a random sample of 500 female hairdressers aged 15-54 years, 355 were available for study. Of the 189 reporting work-related skin and respiratory symptoms in a computer-aided telephone interview on exposure and health, 130 underwent a physical examination, lung funtion tests, prick and patch testing, and nasal and lung provocation tests. An occupational disease was diagnosed when the causality between exposure and disease was probable and the clinical tests supported the diagnosis.Results: The telephone interview revealed a life-time prevalence of 16.9% for hand dermatoses, 16.9% for allergic rhinitis, and 4.5% for asthma among the hairdressers. In the clinical investigations, the prevalence was 2.8% for occupational dermatoses, 1.7% for occupational rhinitis, and 0.8% for occupational asthma. Ammonium perfulfate caused 90% of the respiratory diseases and 27% of the hand dermatoses. Paraphenylenediamine, natural rubber latex, and skin irritation were also causes of hand dermatitis. Allergy to human dandruff (8.6%) and Pityrosporum ovale (12.2%) was common. Previously diagnosed atopic diseases increased the risk for occupational skin or respiratory disease 3-fold (odds ratio 2.9, 95% confidence interval 1.1—7.9). Of the cases, 37.5% (6 of 16 persons) had to change occupations during a 3-year follow-up.Conclusions: Work-related skin and respiratory symptoms are common among hairdressers. Often a specific cause (e.g., ammonium persulfate) can be found if occupational diseases are suspected and diagnosed. Hairdressers with atopic diseases are at risk of developing occupational skin and respiratory diseases.Job demands, muscle activity and musculoskeletal symptoms in relation to work with the computer mouse. C. Jensen, V. Borg, L. Finsen, K. Hansen, B. Juul-Kristensen, H. Christensen. Scand J Work Environ Health, Vol. 24, No. 5, 418-424.Objectives: This study assessed work postures, movements, psychosocial job demands, and shoulder and wrist extensor muscle activity and registered the prevalence of musculoskeletal symptoms of computer-aided design (CAD) operators.Methods: A questionnaire survey was used to study the use of the computer mouse, psychosocial work factors, and musculoskeletal symptoms among 149 CAD operators. A workplace study was performed using observations electrogoniometers on the wrists, and electromyography to measure exposures and physiological responses during CAD work among a subgroup of the CAD operators.Results: Musculoskeletal symptoms were far more prevalent for the arm or hand operating the mouse than for the other arm or hand, and women were more affected than men. The symptoms may be related to such risk factors as repetitive movements, static postures (e.g., ulnar-deviated and extended wrist on the mouse side), and static muscular activation patterns. The risk factors were present due to continuous mouse use and possible also due to high demands for mental attentiveness, precision, and information processing.Conclusions: Exposure during work with a computer mouse may present a risk for devloping musculoskeletal symptoms. Improvements should focus on introducing more variation.Driver behavior at rail-highway crossings. J. Abraham, T. Datta, & S. Datta. Transportation Research Record, 1648. Paper No. 98-0632.A study of driver behavior at 37 rail-highway crossings in Michigan revealed the possible associations between past crash histories and violations. Data collection included recording license plate numbers for violating vehicles, driver gender, approximate age of the driver, and the vehicle make and model. Driver violations were categorized into five different levels of severity ranging from routine to critical. The 37 study sites were subdivided into four groups based on crossing geometry and traffic control. The number of sites in the groups ranged from 5 to 18. Seven years of crash data on the study sites were considered for significance testing. Observed violation data for the same groups were calculated, and tests for statistical significance were performed on them. The results of this study indicated promise for the use of the violation data in determining the relative hazardousness of rail-highway crossings in combination with crash histories. The violation data may also be used to develop countermeasures that would help alleviate violations and eventually traffic crash problems at rail-highway crossing sites. Targeted enforcement as well should assist in driver behavioral modifications. Additionally, the timely arrival of trains after the warning devices are triggered is an essential element that motorists assess when considering taking risks.Airbags: an exploratory survey of public knowledge and attitudes. T. Nelson, D. Sussman, J. Graham. Accident Analysis and Prevention, 31(4), 371-379.The present study examines public knowledge and opinion in the United States on issues related to airbag safety. Data were obtained through a national random digit-dial telephone survey of 1005 people living in the contiguous 48 United States. A majority of respondents (1) know that airbags can harm drivers seated too close to the steering wheel; (2) know that rear-facing infant seats should not be placed in the front seat of a car with passenger-side airbags; and (3) know that airbags are saving more lives of women drivers than are being lost. However, most respondents did not know the (1) airbags are killing more children than they are saving; (2) airbags can injure properly belted drivers; and (3) the majority of the lives saved by airbags have been among people who were not wearing safety belts. Knowledge of airbag risks to children and properly belted drivers was significantly associated with a less favorable attitude toward airbags, and with opposition toward the law mandating airbags on all new cars. Drivers of vehicles equipped with airbags held more favorable attitudes toward airbag technology. Further analysis suggest that as the public begins to understand the risks associated with airbags, the current high level of public support for the technology and the mandatory regulation may decline.The relationship of traffic accidents with personality traits. B. Alparslan, C. Dereboy, S. Savk, H. Kaynak, I. Dereboy, E. Cullu, I. Ozkan, S. Ayaz. J. Traffic Me 27(1-2), 25-30.Objective: This study aims to compare traffic accident involved drivers with non-involved drivers in terms of various personality traits and socioeconomic variables.Methods: Ninety-eight drivers consecutively involved in motor accidents within the first four months of 1997 comprised the study group, whereas 88 non-involved drivers served as the control group. The self-report inventory of SCID-II (Structural Clinical Interview for DSM-III-R) was administered to each subject. In addition, we collected data representing the subjects' sociodemographic characteristics, driving experience, and driver license types.Results: No significant difference was found between the two groups in terms of age, socioeconomic level, marital status, and driving experience. In contrast, there were more males and heavy vehicle drivers in the accident group as compared with the control group. In addition, the accident group received significantly higher scores in half of the SCID-II personality scales, namely, schizotypal, histrionic, borderline, antisocial, dependent and passive-aggressive.Conclusions: Our findings suggest that the accident involved drivers as a group display asocial behaviors, difficulty in impulse control, alertness and aggressive behaviors.Snowboarder's wrist: Its severity compared with Alpine skiing. K. Sasaki, M. Takagi, Y. Kiyoshige, T. Ogino. The Journal of Trauma: Injury, Infection, and Critical Care. 46(6), 1059-1061.Background: Although the upper extremity, especially the wrist, has been reported to be the most commonly injured site in snowboarding, the severity of these injuries is still unknown. The purpose of this study is to compare the severity of wrist injuries in snowboarding with those in alpine skiing for insight into the treatment of snowboarder's wrist.Materials and methods: The cases of 11,598 patient injured while snowboarding and skiing who presented to the Zao clinic during the past 7 seasons were reviewed and compared. Demographics were studied, focusing on fractures around the wrist joint. Roentgenographically precise assessment of the distal radial fracture was performed according to AO classification.Results: Snowboarders were more likely to injure the wrist than were skiers (18.7% vs. 2.5%, p < 0.01). In the wrist injuries, distal radial fractures occurred at a rate of 0.28 per 1000 snowboarders and 0.008 per 1000 skiers. Comminuted and articular fractures classified as AO type A3, B and C, which required surgical treatment, were 49.4% of distal radial fractures in snowboarders and 23.8% in skiers.Conclusion: Wrist injury sustained while snowboarding is characterized as a severe and complex injury. Thus, we call attention to its severity in the treatment of snowboarder's wrist.Children's fractures: a population based study. R.A. Lyons, A.M. Delahunty, D. Kraus, M. Heaven, M. McCabe, H. Allen, P. Nash. Injury Prevention, 5(2), 129-132.Objective: To measure the incidence of childhood fractures in a defined population.Setting: Accident and emergency (A & E) departments covering the Swansea and North Port Talbot areas of South Wales in 1996.Methods: Linkage of data from A & E departments with population data to produce fracture incidence rates by anatomical site and cause in children aged 0-14 years.Results: During 1996, 2463 new fractures occurred in 2399 residents yielding a fracture rate of 35.1/1000 children. Fractures were more common in boys than girls and increased with age in both groups. Sports and leisure activities accounted for 36% of fractures, assaults for 3.5%, and road traffic accidents 1.4%. Fractures of the radius/ulna were most frequent (36%).Conclusions: The fracture rate in South Wales children is twice the rate reported in previous studies. Further research is required to elucidate the reasons behind this high rate. Many fractures could be prevented by the use of safer surfaces in school playgrounds, and wrist protection in in-line skaters and possibly in soccer players.Elevator Accidents. P. Magnus. Elevator World, 47(6), 112-115.The compilation and analysis of accident data involving elevators is of great importance in efforts to eliminate or at least reduce such accidents. The data can clearly show what priorities should be set. This article analyzes the accident data for Israel during a 23-year period (1975-1998), and the results show that the dominant cause for these accidents was the “absence of a car door.” This led to a regulatory demand to install car doors retroactively. The second dominant cause was “falling into the elevator shaft,” stressing the importance of inspection and maintenance of the door locks. Furthermore, the data point to the need to train elevator technicians on a periodic basis to emphasize the importance of correct and safe work methods, for their own good and for the benefit of the passengers. The intervention of untrained and unauthorized personnel is dangerous and must be forbidden. This should be enforced vigorously.  相似文献   
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