崇明岛风景旅游区空气负离子监测评价方案研究

崇明岛作为上海市的未来生态岛屿,至今尚未开展过系统的空气负离子研究。依据该县相关规划,结合区域植被、地貌、人为影响等因素,在东滩国家级自然保护区、东平国家森林公园、前卫村、明珠湖和西沙湿地5个监测区域共选定了18个空气质量监测点进行研究。按崇明风景旅游区的具体情况,对国内外7种空气负离子监测评价方法进行了比较,最终确定选用安培空气质量评价系数、森林空气离子评价系数、空气负离子系数评价法、轻重离子比评价法来对该岛的空气质量进行评价。最后还对相关负离子监测仪器进行了分析及建议。     

坡度对跨座式单轨隧道临界风速的影响

为研究不同坡度隧道在大功率火源情况下的烟气运动,采用1∶20的缩尺隧道模型,通过试验对不同坡度情况下(-6%,-3%,0%,3%,6%)的大火源功率火灾(20,50 MW)时的隧道纵向通风临界风速进行研究。结果表明:0%坡度时,20 MW和50 MW的临界风速相差不大;有坡度时,逆坡送风的临界风速大于顺坡送风的临界风速。根据试验结果拟合得出大火源功率(20,50 MW)条件下坡度为-6%至6%时的临界风速与坡度的关系,并对前人提出的坡度与临界风速的关系式进行修正。     

熵权法在铀矿井下空气环境安全评价中的应用研究

为科学合理地评价铀矿井下空气环境质量,通过对广东某铀矿及辽宁某铀矿井下空气环境的调查,分析了铀矿井下空气环境的特点及其危害,确定氡、氡子体、铀矿尘、CO、NO2及矿井气候6个指标为影响铀矿井下空气环境质量的主要因素,依此建立铀矿井下空气环境安全评价指标体系.采用模糊综合评价法建立了铀矿井下空气环境安全评价模型,并采用熵权法客观赋权的方式确定各评价指标权重,避免了评价过程中人为主观因素的影响,从而得到比较客观的评价结果.以南方某铀矿井为例,运用建立的评价模型对其井下采场、巷道掘进、天井掘进3个工作面空气环境质量进行安全评价.结果 表明,采场工作面空气环境质量为良好,巷道掘进工作面和天井掘进工作面空气环境质量为中等.其评价结论可为企业优化井下工作场所空气环境质量提供参考.     

Methane emission via sediment and water interface in the Bohai Sea, China

Sediment is recognized as the largest reservoir and source of methane (CH₄) in the ocean, especially in the shallow coastal areas. To date, few data of CH₄ concentration in sediment have been reported in the China shelf seas. In this study, we measured CH₄ concentration in sediment and overlying seawater columns, and conducted an incubation experiment in the Bohai Sea in May 2017. CH₄ concentration was found to be ranged from 3.075 to 1.795 μmol/L in sediment, which was 2 to 3 orders of magnitude higher than that in overlying seawater columns. The surface sediment was an important source of CH₄, while bottom seawater acted as its sink. Furthermore, the net emission rate via sediment water interface (SWI) was calculated as 2.45 μmol/(m²∙day) based on the incubation experiment at station 73, and the earthquake may enhance CH₄ release from sediment to seawater column in the eastern Bohai Sea.     

矿产资源资产化管理理论和方法的分析与展望

本文全面地介绍了矿产资源资产化管理及资产评估的国内外研究现状，系统地总结了在矿产资源价值、矿产资源资产评估、矿产资源资产化管理、资源耗竭—补偿、资源核算等方面的研究成果，并对这一课题的研究提出了建议     

亚甲蓝褪色反应测定水中痕量锰

本文提出和建立了一个新的催化动力学测定痕量锰的方法。它是基于在醋酸-醋酸钠介质中,锰对高碘酸钾氧化亚甲蓝褪色反应所具有的催化效应。在最佳条件下,用固定时间法,可测5—80ng/27ml范围内的锰。应用于水样测定,获得满意结果     

下吸式气化炉处理城市生活垃圾

下吸式气化炉具有原料适应性好，燃气中焦油含量少的特点。使用下吸式气化炉对广州城市生活垃圾进行了空气气化实验，并对燃气成分、焦油含量和灰渣重金属含量进行了分析。分析结果表明：燃气气体热值可达4600kJ／m^3，燃气焦油含量为2．0g／m^3。另外，对灰渣中的金属成分也进行了分析。试验结果表明：下吸式气化炉是处理复杂城市生活垃圾的一种有效手段。     

松花江表层沉积物中16种多环芳烃空间分布特征及生态风险评价

为揭示松花江干支流表层沉积物中16种PAHs（多环芳烃）的空间分布特征及其生态风险状况,采用气相色谱-质谱联用仪分析了2017年9月松花江干支流26个表层沉积物16种PAHs质量分数特征,并采用比值法对其污染来源进行解析,运用沉积物质量基准法和质量标准法评价其生态风险状况.结果表明:①松花江干支流表层沉积物中w（∑₁₆PAHs）为169.76~3 769.19 ng/g,以3~6环高环为主,并且支流w（∑₁₆PAHs）（范围为169.76~3 769.19 ng/g,平均值为1 598.41 ng/g）高于干流（范围为459.92~2 092.58 ng/g,平均值为1 173.67 ng/g）,呈从上游到下游逐渐降低的趋势.②松花江干支流表层沉积物中w（∑₁₆PAHs）主要来源于生物质燃烧和石油燃烧.③松花江干支流表层沉积物中w（∑₁₆PAHs）总体处于低生态风险水平,个别支流点位（3个）会发产生经常性生态风险.研究显示,松花江流域干支流表层沉积物中w（∑₁₆PAHs）呈从上游到下游逐渐降低的趋势,并且支流高于干流,但总体处于低生态风险水平.      

Evaluation of sulfur trioxide detection with online isopropanol absorption method

Measurement of the SO_3 concentration in flue gas is important to estimate the acid dew point and to control corrosion of downstream equipment. SO_3 measurement is a difficult question since SO_3 is a highly reactive gas, and its concentration is generally two orders of magnitude lower than the SO_2 concentration. The SO_3 concentration can be measured online by the isopropanol absorption method; however, the reliability of the test results is relatively low. This work aims to find the error sources and to evaluate the extent of influence of each factor on the measurement results. The test results from a SO_3 analyzer showed that the measuring errors are mainly caused by the gas–liquid flow ratio, SO_2 oxidation, and the side reactions of SO_3. The error in the gas sampling rate is generally less than 13%. The isopropanol solution flow rate decreases 3% to 30% due to the volatilization of isopropanol, and accordingly, this will increase the apparent SO_3 concentration. The amount of SO_2 oxidation is linearly related to the SO_2 concentration. The side reactions of SO_3 reduce the selectivity of SO_4~(2-) to nearly 73%. As sampling temperature increases from180 to 300°C, the selectivity of SO_4~(2-) decreases from 73% to 50%. The presence of H2 O in the sample gas helps to reduce the measurement error by inhibiting the volatilization of the isopropanol and weakening side reactions. A formula was established to modify the displayed value, and the measurement error was reduced from 25%–54% to less than 15%.