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71.
农产品安全问题直接关系到消费者的健康和生命.上海市作为一个开放型的国际化大都市,借鉴国内外经验,结合上海经济发展的实际情况,建设一个与国际接轨的输入型农产品安全监管体系已成为当务之急.本文通过分析上海市输入型农产品安全监管的现状、特点及存在的问题,明确了构建上海市输入型农产品安全监管体系的指导思想和建设目标,提出了当前上海市输入型农产品安全监管的对策与建议.  相似文献   
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73.
采用填料塔对铁盐溶液吸收 H2 S的过程进行了初步研究 ,考察了气液比、填料层高度、吸收温度、Fe3+浓度、进气 H2 S浓度和 H+浓度等因素对 H2 S去除率的影响。结果表明 ,气液比、填料层高度和吸收温度对吸收效率的影响比较显著。通过正交试验选出最佳工艺条件 ,在此工艺条件下 H2 S的去除率接近 10 0 %。  相似文献   
74.
为了避免在修井过程中产生的落地油、油砂、油水混合液和洗井液等对环境造成污染,辽河石油勘探局经过多年的研究与实践已研究出一整套完备的绿色环保修井技术,包括抽油杆刮油、油管泄油、密闭连续冲砂、软捞砂、快速防喷、汽化水回收等修井技术,在施工全过程中采取了预防污染的措施,将生产技术、生产过程、经营管理及产品质量与物流、能量、信息管理等有机结合起来,并优化运行方式,从而实现了最小的环境影响、最少的资源消耗、最佳的管理模式以及最优化的经济水平。并取得多项专利成果。  相似文献   
75.
端面顶板是高档普采工作面顶板管理的重点,分析了п型钢梁支护法的不足,提出了一种新的支护方法,通过应用取得了良好效果。  相似文献   
76.
Lau MC  Chan KM  Leung KM  Luan TG  Yang MS  Qiu JW 《Chemosphere》2007,69(1):135-144
Experiments were performed to determine the acute and chronic toxicities of tributyltin (TBT) (nominal concentrations) to polychaete Hydroides elegans. Firstly, static tests were performed to examine the lethal effect of TBT on five life stages of H. elegans. The 48-h LC(50) (95% CI) for the eggs, 2-cells, trochophores, juveniles and adults was 0.18 (0.15-0.20), 0.97 (0.77-1.23), 2.36 (2.11-2.65), 2.86 (2.63-3.12) and 4.36 (4.04-4.71) microg TBT l(-1), respectively. Secondly, a 17-d static renewal chronic test was conducted to study sensitivity of the early development (egg to juvenile) to TBT. The survivorship, percent settlement and time to reach settlement were significantly reduced at 0.01 microg TBT l(-1). Effects of TBT on the juvenile growth and maturation were also studied through a 44-d chronic test. Lower survivorship and reduced tube growth were observed only at >or= 1 microg TBT l(-1), however, only H. elegans exposed to or= 0.1 microg TBT l(-1). Our results indicate that the early development of H. elegans is highly sensitive to TBT and this polychaete can be routinely employed as a test organism for both acute and chronic ecotoxicity bioassays in tropical and subtropical regions such as southern China.  相似文献   
77.
废弃印刷线路板资源化处理的研究进展   总被引:9,自引:2,他引:7  
介绍了当前废弃印刷线路板资源化处理的主要方法,包括湿法、火法、机械法、生物法、超临界流体法和等离子体熔炼法等。综述了各种处理方法的侧重点及利弊;提出热解法与机械法联用可较好地解决在破碎过程中所遇到的问题,具有较大优势,可作为未来大量废弃印刷线路板资源化处理工艺研究的重点。  相似文献   
78.
OBJECTIVES: The majority of motor vehicle occupants who were killed or hospitalized in crashes in Kentucky in 2000-2001 occupied vehicles that were severely damaged in the crash. Even so, overall only a small percentage of all severely damaged vehicle occupants were killed or hospitalized. The purpose was to identify occupant, vehicle, crash, and roadway/environmental factors that were associated with increased risk of severe injury in crashes where the occupant's vehicle was severely damaged. METHODS: This study probabilistically linked Kentucky's statewide motor vehicle crash and inpatient hospital discharge data files for 2000 and 2001, and selected cases representing occupants of vehicles that were reported by police as having either "severe" or "very severe" damage. For occupants who were identified through data linkage as having been hospitalized, the Injury Severity Score (ISS) was calculated using ICDMAP-90 software, and the scores were stratified into the following categories: critical (>24), severe (15-24), moderate (9-14), and mild (<9). We then created an outcome variable, injury severity level, with five levels: killed; hospitalized with at least moderate injuries (ISS = critical, severe, or moderate); hospitalized with mild injuries (ISS = mild); injured according to the police report but not hospitalized; and no apparent injury according to the police report. We performed a stepwise, ordinal logistic regression of injury severity, using independent variables identified from the existing crash literature. RESULTS: Occupant risk factors for higher levels of injury severity selected by the regression were age (risk increased with age, other factors being equal), female gender, restraint non-use, ejection from the vehicle, and driver impairment (by alcohol and/or drugs). Crash risk factors included head-on collision, collision with a fixed object, vehicle rollover, and vehicle fire. Roadway/environmental factors were federal- or state-maintained roadway and posted speed limit 89 kph (55 mph) or greater. CONCLUSIONS: Many of the identified risk factors are explicitly or implicitly mentioned in the strategic plans of key organizations involved in highway safety and injury prevention in Kentucky. Our analysis provides additional evidence of their importance, and confirms that their mitigation will reduce injury severity in crashes involving severe vehicle damage. Additionally, older occupants and female occupants showed increased risks of serious injury, but to our knowledge these factors are not currently addressed in any state plans. An opportunity exists to clarify the nature of these risks through further studies, which might lead to the identification of countermeasures specific to these populations.  相似文献   
79.
The aim of this study is to investigate conversion of nitrogen and COD in enriched paddy soil by nitrification coupled with anammox process in a dual chamber bioelectrochemical system. The paddy soil was enriched for denitrification coupled with anammox by microbial consortia and was acclimatized in the cathodic chamber of microbial fuel cells(MFCs). The bioelectrochemical systems were treated with different ammonium concentrations in the cathodic chamber: the MFC with low concentration ammonium...  相似文献   
80.
分析了回采工作面回柱放顶作业中防护措施的不足,介绍了DTH推护器的结构和现场应用效果.  相似文献   
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