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71.
温州城市降雨径流中BOD5和COD污染特征及其初始冲刷效应 总被引:2,自引:1,他引:1
为研究温州降雨径流污染情况,监测了温州2个采样区4场较为典型的降雨过程,测定了不同下垫面径流中BOD5和COD的浓度,并且计算出污染物的EMC值、M(V)曲线和BOD5/COD值等.结果表明,温州城市降雨径流中BOD5和COD的含量分别介于ND~69.21 mg.L-1和ND~636 mg.L-1之间,不同城市下垫面径流中BOD5和COD的含量均随着降雨历时的延长而呈下降趋势,处理初期径流水样对减少耗氧性有机污染具有重要意义.从COD和BOD5的EMC值来判断,部分城市下垫面降雨径流中污染物浓度超出地表五类水标准,甚至高于污水排放二级标准,此类降雨径流若直接入河将对下级受纳水体造成耗氧性有机污染的压力.根据M(V)累积曲线判断,COD初期冲刷效应在城市降雨径流中是较为普遍的,城市降雨径流中的BOD5表现出与COD类似的初始冲刷情况,该结果亦表明径流初期耗氧性有机污染严重.城市降雨径流中COD和BOD5的浓度受下垫面类型和降雨条件的影响,而BOD5/COD指标的变化特征则指出生物降解是削减有机污染负荷的有效途径之一,但不同下垫面径流有机污染的治理工作应采用不同的最佳管理方案(BMPs). 相似文献
72.
应急管理第一响应者制度综述 总被引:1,自引:0,他引:1
第一响应者最早产生于医疗紧急救护中,属于志愿服务,并在欧美国家得到发展和广泛运用。美国在交通事故管理和突发事件应对中发展了第一响应者的概念,一是服务内容从医疗救护扩大至其他突发事件应急管理,二是第一响应者不仅限于志愿服务,也包括专业机构首先到达现场的人。我国历史上曾有赤脚医生、辅助警察等现实意义的第一响应者制度,但我国目前的第一响应者主要集中在突发事件信息员,特别缺乏应急处置的第一响应者。中德政府合作的搜索救援"第一响应者"培训对第一响应者进行了新的定义,增加了现场组织管理能力培训。我国应该大力培训应急救援"第一响应者"教官,并逐步制定有关志愿服务法律。 相似文献
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Julene S. Carvalho 《黑龙江环境通报》2004,24(13):1060-1067
The detailed study of the fetal cardiac anatomy in the first trimester of pregnancy by means of ultrasound, transvaginally or transabdominally, is feasible and remains a safe procedure provided thermal and mechanical indices are taken into account. Optimal time for successful imaging of the four chambers and great arteries in early gestation appears to be between 13 to 14 weeks. In experienced hands, first-trimester fetal echocardiography is accurate in detecting major structural cardiac abnormalities and yields a high negative predictive value. Thus, in a clinical setting, it can be offered to families considered to be ‘at risk’ of cardiac defects (e.g. those with previous family history or when fetal nuchal translucency is increased) and can be a powerful tool to reassure families regarding normality of major cardiac structures and connections. However, the early detection of an important structural abnormality (chromosomally normal or not) may be associated with a high termination rate if this is an acceptable option. The high prevalence of associated chromosomal and extracardiac abnormalities for many of the high-risk families, who may benefit from this approach, cannot be ignored. Therefore, fetal heart scanning in the first trimester should be performed in conjunction with detailed first-trimester obstetric scanning. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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Min Chen Dr Yung Hang Lam Chen Lung Lin Kwok Wah Chan Pui Wah Hui Mary Hoi Yin Tang Chin Peng Lee Pek Lan Khong 《黑龙江环境通报》2002,22(12):1067-1070
Enteric duplication cyst is a congenital abnormality that is believed to arise from abnormal recanalization of the bowel during embryogenesis. Previous reports suggest that the condition may be suspected prenatally by sonographic demonstration of an intra-abdominal cystic mass in the second and third trimesters. We present the sonographic features of a fetus with ileal duplication cyst at 12 weeks of gestation, which show that the condition may present in the first trimester of pregnancy. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
78.
Initially described in 1972, Bartsocas–Papas syndrome (BPS) is an autosomal recessively inherited disorder combining multiple pterygia, ankyloblepharon, cleft lip and palate, filiform bands between the jaws, syndactyly, and other anomalies. Although described as lethal, review of the literature reveals three individuals who survived into childhood with this condition. We describe a fourth surviving patient and what we believe to be the first prenatal diagnosis of BPS in the first trimester. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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B. Masturzo J. A. Hyett K. D. Kalache G. Rumsby E. Jauniaux C. H. Rodeck 《黑龙江环境通报》2001,21(4):314-316
We present two cases of pregnant women with a previous history of congenital adrenal hyperplasia. In both cases the only abnormal feature in the initial pregnancy had been increased nuchal translucency at 10–14 weeks of gestation. The fetal karyotype was normal and a diagnosis of congenital adrenal hyperplasia was made after delivery. In their current pregnancies, both fetuses also had increased nuchal translucency and normal fetal karyotype. Diagnosis of 21-hydroxylase deficiency was made prenatally by DNA analysis. These findings in four affected fetuses suggest that congenital adrenal hyperplasia should be added to the list of genetic anomalies associated with an increase in nuchal translucency. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献