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51.
52.
对一起典型的电梯安全质量方面的司法技术鉴定案例进行了分析,找出了现场鉴定电梯不符合安全技术规范的具体项目,详细分析了电梯制造、安装、检验、重大维修、维护保养过程中的违反安全技术规范的具体内容,并分析了相关环节责任主体的责任。  相似文献   
53.
采用走航巡测模式对2020年长江重庆—武汉段水质状况开展调查分析,并对192个巡测点位38项自动监测参数进行统计、评价、分析。结果表明:长江重庆—武汉段水质良好,全部达到或优于Ⅲ类水标准,各参数测定值水平整体不高;部分点位水质参数存在明显测定峰值,在一定程度上反映〖JP2〗周边水域受到潜在污染影响;城市江段、产业园区、港口码头、航运频繁水域污染物测定值相对增高,仍须将聚集性区域作为污染防控重点,〖JP〗加大减排力度,降低长江水污染潜在风险。  相似文献   
54.
We studied pregnancy-related changes in serum concentrations of five polychlorinated biphenyls (PCBs, CB 118, CB 138, CB 153, CB 156, CB 180), three hydroxylated PCB metabolites (4-OH-CB107, 4-OH-CB146, 4-OH-CB187), and pentachlorophenol (PCP). Median serum lipid content increased 2-fold between early (weeks 9-13) and late pregnancy (weeks 35-36) (N = 10), whereas median PCB levels in serum lipids decreased 20-46%, suggesting a dilution of PCB concentrations in serum lipids. Nevertheless, strong positive intra-individual correlations (Spearman’s r = 0.61-0.99) were seen for PCBs during the whole study period. Thus, if samples have been collected within the same relative narrow time window during pregnancy, PCB results from one single sampling occasion can be used in assessment of relative differences in body burdens during the whole pregnancy period. Concentrations of OH-PCBs in blood serum tended to decline as pregnancy progressed, although among some women the concentrations increased at the end of pregnancy. Positive intra-individual correlations (r = 0.66-0.99) between OH-PCB concentrations were observed during the first and second trimester, whereas correlations with third trimester concentrations were more diverging (r = −0.70-0.85). No decline in PCP concentrations was observed during pregnancy and no significant correlations were found between concentrations at different sampling periods. Our results suggest that for both OH-PCBs and PCP, sampling has to be more specifically timed depending on the time period during pregnancy that is of interest. The differences in patterns of intra- and inter-individual variability of the studied compounds may be due to a combination of factors, including lipid solubility, persistence of the compounds, distribution in blood, metabolic formation, and pregnancy-related changes in body composition and physiological processes.  相似文献   
55.
以现代环境伦理观为指导分析修改水污染防治立法目的,然后以水权体系构建水环境管理权体系来完善水污染防治管理体制,最后从法律责任方式角度提出了完善水污染防治法律责任制度的建议,以期促进水污染防治法的完善,保障和改善我们赖以生存的水环境。  相似文献   
56.
于秋冬两季,利用法国生产的自动监测仪对重庆市城区7条交通主干道的近地面空气质量进行了监测。结果表明:在监测期间,各个监测点PM1o是首要污染物,并且秋季比冬季污染严重,7条道路的日平均浓度为0.419mg/m^3,最大浓度为0.687mg/m^3,最大超标率为3.58倍;而NO2和SO2在冬季比秋季污染严重,NO2最高浓度是0.126mg/m^3,平均浓度是0.089mg/m^3,S02最高浓度是0.333mg/m^3,平均浓度是0.216mg/m^3,表明交通干道空气污染严重。  相似文献   
57.
 Rapid social and economic development in China has caused the amount of hazardous wastes being generated to increase drastically. The necessary regulations and systems regarding the management of hazardous wastes are currently still not in place. Based on an analysis of the characteristics of hazardous waste pollution and pollution trends in China, this paper reports on China's current status regarding hazardous waste management, and introduces the main difficulties to be faced. The principles and objectives, and the action plan for hazardous waste pollution control in China are also explained in detail. These principles and objectives have been stipulated in the Technological Policies on Hazardous Waste Pollution Control, which is issued by China State EPA, State ETC, and the Science and Technology Ministry. Received: April 30, 2002 / Accepted: October 17, 2002  相似文献   
58.
59.
Eighty-eight cases of abdominal wall defect with and without other lesions were ascertained by reviewing all labour room records in the West of Scotland, all surgical admissions to the Royal Hospital for Sick Children, Yorkhill, and all post mortems at Royal Hospital for Sick Children between 1978 and 1981. The affected cases comprised 39 terminations of pregnancy (17 of anterior abdominal wall defect without neural tube defect). 20 spontaneous stillbirths and 29 livebirths. All 10 cases of body stalk anomaly, 37.5 per cent of 16 gastroschisis cases and 53 per cent of 62 exomphalos cases had additional severe abnormalities. Abnormal karyotypes were present in seven out of 19 exomphalos cases but all karyotypes from 10 gastroschisis and 6 body stalk anomaly cases were normal. No correlation was found between the maternal serum AFP levels, the amniotic AFP levels and acetylcholinesterase results and the size of the lesion. It is proposed that anterior abdominal wall defects detected prenatally should have chromosome analysis and careful ultrasound to exclude associated severe anomalies before coming to a decision about termination. This policy was implemented in six pregnancies complicated by fetal gastroschisis without severe associated anomalies which were identified in the second trimester and continued to term. Immediate surgical repair was achieved in each case, although two of the infants succumbed from later complications of gastroschisis closure and one from respiratory distress syndrome. The remaining three infants made a satisfactory recovery.  相似文献   
60.
An experiment was designed to examine in a long-lived seabird, the thin-billed prion (Pachyptila belcheri), how adults adjust their food provisioning strategy when their foraging abilities are reduced and when the chick's needs are increased. To reduce the foraging abilities of adults we impaired their flying ability by removing some flight feathers (handicapped), and to increase the food needs of the chick one parent was retained (single). Birds made either short foraging trips lasting 1–3 days, or long trips lasting 5–9 days. Control birds alternated long and short trips whereas single birds or handicapped birds made several successive short trips and thereafter a long trip. In each treatment, food loads tended to be heavier after long trips than after short trips, and single birds tended to bring heavier loads than control or handicapped birds. Birds in the three treatments lost similar amounts of mass after short trips and gained similar amounts of mass after long trips. However, the mass of handicapped birds declined through the experiment, while that of control and single birds remained stable. Although the proportion of chicks that died during the experiment was similar among the three treatments, the chicks fledged by a single bird were lighter than those in control nests. The results of the experiment suggest that thin-billed prions adjust their breeding effort differently to decreased flying ability or increased food demand by the chick. Single birds increase foraging effort without allowing their condition to deteriorate. Conversely, handicapped birds are unable to maintain their body condition while sustaining the chick at the same rate as control birds. It is suggested that in this long-lived seabird, adults probably adjust their breeding effort so that they do not incur the risk of an increased mortality, this risk being monitored by the body condition.  相似文献   
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