环空带压气井液位测试方法改进研究及应用

为了实时有效监测环空带压气井的液面位置,评价环空带压气井的风险,在传统回波定位技术基础上,提出了1种基于自相关分析的气井液位声波测试方法;建立了环空液位声波测试实验系统,开展了不同起爆压力下环空液位测试实验;对检测到声波信号进行平滑降噪和自相关分析,计算液面位置,并与真实液位进行对比分析;将该方法在现场含噪声的环空带压气井液位测试中进行了应用。结果表明:该方法能够对环空液位声波测试信号中的液面反射波进行有效提取;相比较现有在测试信号平滑降噪基础上提取的液面位置,降低了计算误差;同时,该方法能够在井下噪声环境中实现微弱液面反射声波的有效提取,其处理后的信号峰值指标更为突出,提高了测试系统对液位的识别能力,便于自动识别。     

热重实验条件下不同氧气浓度对煤自燃反应能级的实验研究

为研究不同氧气浓度对煤自燃反应能级的影响,基于热重实验分别得到6个不同氧气浓度下的煤自燃特征温度点,通过计算不同阶段内煤自燃的反应动力学参数分析氧气浓度与煤自燃反应能级关系。实验结果表明:n≠1时,氧气浓度对煤自燃反应能级(n)的影响在不同温度段内的影响不同;氧气浓度与T1,T2,T3特征温度点的关系曲线变化趋势不明显,T4~T8温度点与氧浓度的关系呈现先增大后减小的趋势。     

滹沱河超采区地下水回补的水化学效应研究

由于长期超采地下水,导致滹沱河冲洪积平原地下水位持续下降,水质恶化,为缓解滹沱河超采区水资源矛盾,2018年开始实施了河道回补工程,回补水源为黄壁庄水库水和“南水北调”水.为了研究回补后地下水化学效应变化,应用水文地球化学、水文学和统计学等理论方法,开展了现场动态监测、地下水化学检测工作.结果表明:①实施滹沱河补水后地下水位上升显著,滹沱河沿线地下水位平均回升5.83 m;2019年较2015年滹沱河超采区地下水位平均回升5.93 m,地下水漏斗形状发生改变,地下水向漏斗中心汇集已不明显.②滹沱河多年受上游高硫酸盐水源补给的影响,滹沱河沿岸分布HCO₃·SO₄-Ca·Mg型地下水,并在HCO₃·SO₄-Ca·Mg型水两侧形成了条带状的HCO₃·SO₄·Cl-Ca·Mg型水.与2015年相比,2019年HCO₃-Ca·Mg型水的面积减少了20.6%,HCO₃·SO₄·Cl-Ca·Mg型水和HCO₃·SO₄-Ca·Mg型水的面积增加了13.6%.③河道补给有效缓解了地下水环境恶化,区域地下水中硫酸盐平均含量基本持平,氯化物浓度、TDS（溶解性总固体）浓度、总硬度呈下降趋势;受上游黄壁庄水库补水影响,滹沱河沿岸附近地下水中硫酸盐的浓度升高,高浓度的硫酸盐主要分布在滹沱河、石津灌渠及黄壁庄水库副坝附近,随着补水的不断推进,水位持续回升,在水动力作用下,其有向下游扩散的趋势.研究显示,科学合理地选择补水水源与回补方式是减缓该地区地下水硫酸盐污染及保持地下水可持续利用的有效方式.      

Impacts of n-alkane concentration on soil bacterial community structure and alkane monooxygenase genes abundance during bioremediation processes

Petroleum hydrocarbons, mainly consisting of n-alkanes and polycyclic aromatic hydrocarbons (PAHs), are considered as priority pollutants and biohazards in the environment, eventually affecting the ecosystem and human health. Though many previous studies have investigated the change of bacterial community and alkane degraders during the degradation of petroleum hydrocarbons, there is still lack of understanding on the impacts of soil alkane contamination level. In the present study, microcosms with different n-alkane contamination (1%, 3% and 5%) were set up and our results indicated a complete alkane degradation after 30 and 50 days in 1%- and 3%-alkane treatments, respectively. In all the treatments, alkanes with medium-chain length (C₁₁-C₁₄) were preferentially degraded by soil microbes, followed by C₂₇-alkane in 3% and 5% treatments. Alkane contamination level slightly altered soil bacterial community, and the main change was the presence and abundance of dominant alkane degraders. Thermogemmatisporaceae, Gemmataceae and Thermodesulfovibrionaceae were highly related to the degradation of C₁₄- and C₂₇-alkanes in 5% treatment, but linked to alkanes with medium-chain (C₁₁-C₁₈) in 1% treatment and C₂₁-alkane in 3% treatment, respectively. Additionally, we compared the abundance of three alkane-monooxygenase genes, e.g., alk_A, alk_P and alk_R. The abundance of alk_R gene was highest in soils, and alk_P gene was more correlated with alkane degradation efficiency, especially in 5% treatment. Our results suggested that alkane contamination level showed non-negligible effects on soil bacterial communities to some extents, and particularly shaped alkane degraders and degrading genes significantly. This study provides a better understanding on the response of alkane degraders and bacterial communities to soil alkane concentrations, which affects their biodegradation process.

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Pesticide residues in products of plant origin in the European Union

The results of a co-ordinated monitoring programme for pesticide residues in the European Union and Norway carried out in 1996 and 1997 are presented. The aim of this programme is to work towards a system, which makes it possible to estimate actual dietary pesticide intake for the population of the European Union. Based on a statistically dérived sampling plan and within the limited number of pesticides/commodities analysed, the most critical pesticides (benomyl group and dithiocarbamates) and commodities (mandarine and lettuce) were identified. In case of detected non-compliances, repeated sampling and, if necessary, enforcement actions are to be taken by national authorities. The programme will be continued in the next years.     

Mapping Land-Cover and Mangrove Structures with Remote Sensing Techniques: A Contribution to a Synoptic GIS in Support of Coastal Management in North Brazil

This article deals with the development and application of a cartographic database for a synoptic Geographic Information System (GIS). Its purpose is the storage and evaluation of the heterogeneous datasets of the interdisciplinary scientific research program MADAM (Mangrove Dynamics and Management), which aims to develop recommendations for a tailored integrated coastal management scheme for the mangrove ecosystem at Bragança (North Brazil). The article describes the integration of remote sensing data, aerial photographs, as well as point data provided by fieldwork from different scientific fields. Using various innovative processing techniques and different scale-resolution levels, an assessment of temporal–spatial changes of the mangrove peninsula and the adjacent rural socioeconomic impact area, the type of mangrove structure, as well as a land-use cover analyses was undertaken. The definition of the spatial level of detail was found to be a major issue in the development of the GIS, as well as during the processing and analysis procedures. A division between strong and weak patterns in the mangrove ecosystem could be made, which implies different management measures and sets of specific interdisciplinary studies and monitoring at hierarchical scales.     

再论在《授予博士、硕士学位和培养研究生的学科、专业目录》中设立“安全科学与工程”一级学科

从社会必要性、现实可行性、学科的实践基础、学科的科学基础、学科的结构体系等方面,对在《授予博士、硕士学位和培养研究生的学科、专业目录》中设立“安全科学与工程”一级学科进行了论述,提出了“安全科学与工程”下设二级学科、专业的框架;阐述了“安全科学与工程”和其他与安全学科相关学科的关系、生源关系、与现有安全学科相关的二级学科的关系、与现有安全学科相关的二级学科的学位授予关系以及与其他学科的学缘关系。论证结论表明目前设立“安全科学与工程”一级学科,条件已经成熟。建议国务院学位委员会尽快将“安全科学与工程”单列为一级学科,并在其下设“安全科学”、“安全工程”2个二级学科、专业。     

人群疏散中"非适应性"行为的研究

本文从人与人的相互作用和社会学、心理学的角度,对人群疏散中“非适应性”行为的理论、计算机模型、模拟原理等进行了较为深入的研究,并以具体实例说明了Building Exodus软件在人群疏散模拟分析中的具体应用,为完善该研究方向的计算机模型和促进软件的开发提供理论和方法的指导.文章得出的结论是：“非适应”人群行为的研究需要从心理学和社会学的角度建立人群中个人行为与社会行为的理论框架.“非适应”人群行为的研究方法必须与紧急情况相结合,而紧急情况是一个由多个人员组成的复杂系统,大量人群环境的模拟需要涉及到人与人之间,人与环境之间的相互作用.     

海平面上升的灾害效应及其研究现状

海平面上升是全球变暖和沿海地区人类活动加剧的必然结果,海平面上升加剧了沿海灾害,威胁着沿海地区社会经济的持续发展.文章分析了海平面上升引起的风暴潮加剧、海岸侵蚀、潮滩湿地减少、涵闸废弃、洪涝灾害加剧、海堤破坏、海水入侵等灾害效应及研究现状,提出当前海平面上升灾害效应研究中存在的问题及今后的研究重点.     

中国城市自然灾害区划编制

依据灾害系统理论和中国自然灾害数据库,构建了综合城市化水平(C1)指标和综合自然灾害强度(QC)指标;运用数字地图技术,在模型与图谱互馈过程中,实现了中国城市承灾体与致灾因子的综合定量评价,编制了中国城市自然灾害区划图.将中国区划为3个一级区,即沿海城市灾害区、东部城市灾害区和西部城市灾害区,以及15个二级区和22个三级区,为城市灾害风险管理和中国自然灾害救助区划提供了科学依据.