长三角空气质量区域预报准确性评估方法研究

根据长三角空气质量区域预报工作的实际需要,对分区文字预报和落区图预报两种方式分别制定了不同的空气质量指数级别预报准确性评估方法。分区文字预报根据设定的预报准确性判定方法计算预报评分,落区图预报按区域内预报准确城市占比进行准确率统计。分区文字预报结果显示,2017年长三角区域的预报准确天数占比为62.2%,预报评分为70.2,区域预报评估效果良好。落区图预报评估结果显示,预报级别偏差具有地域性差异,安徽北部、江苏北部和江西中北部预报等级偏高,长三角中南部沿海城市预报等级偏低。该套评估方法可为区域空气质量预报偏差成因分析提供依据,为区域预报工作的改进提供定量参考。     

射阳湖浮游动物群落结构特征及其与环境因子相关性研究

2016—2017年对射阳湖开展浮游动物群落结构和水质指标逐月监测。结果表明,射阳湖共鉴定出浮游动物61种,其中原生动物、轮虫、枝角类和桡足类分别为25种、24种、7种和5种。浮游动物种类数呈现春夏季多于秋冬季的变化趋势。浮游动物优势种数量较多、分布广,群落结构相对复杂且稳定。运用Shannon-Wiener指数、均匀度指数和B/T指数对射阳湖水质作评价,结果表明,该湖处于轻度—中度污染状态,生物学指标评价法与常规水质评价结果一致。浮游动物群落结构与水质指标相关性分析表明,水温、透明度、Chl-a和DO是影响射阳湖浮游动物群落结构的主要水质指标。     

川中遂宁地区红层地下水水化学特征及主要离子来源分析

四川红层区居民用水主要为就近开采的地下水,水质参差不齐,研究红层地下水水文地球化学特征,对于宜井区选择,红层水源地用水安全具有重要意义。利用在遂宁船山区采集的70组浅层地下水水样,采用数理统计分析、离子比例关系等方法,分析了红层浅层地下水水化学特征及主要离子来源,研究得出:区内地下水中阴离子以HCO_3~-(164.00～571.91 mg·L~(-1))为主,其次是SO_4~(2-)(13.96～1 000.00 mg·L~(-1)),阳离子以Ca~(2+)(45.70～313.00 mg·L~(-1))为主,其中孔隙水的水化学类型主要为HCO_3,SO_4-Ca,SO_4-Mg型,裂隙水以HCO_3-Ca,Mg型与HCO_3-Ca型为主;地下水中离子成分主要由岩石风化产生,来源于地层中的方解石、白云石、石膏、芒硝等矿物的风化溶解,蒸发浓缩、地下水酸碱环境及人类活动对地下水成分造成了一定的影响;浅层地下水质量以Ⅲ～Ⅳ类为主,污染物主要为TDS、Fe~(3+)等原生污染,也存在NO_3~-、NO_2~-等人类活动污染;红层宜井区主要为平坝、丘坡坡脚及沟谷一带,为避免污染指标超标,井深不宜超过25m,远离养殖场、农厕等地下水易受人类活动污染的环境,防止鱼塘、农田等地表水进入井中。     

不同喷雾方式下低阻文丘里振弦栅除尘配置优化实验研究

为了对比径向外喷和轴向喷雾下的低阻文丘里振弦栅耦合除尘效果，以除尘效率和系统阻力为参照，选定喉管气速、振弦栅数、纤维丝间隙和喉管液气比进行单因素实验。结果表明2种喷雾方式的除尘效率和系统阻力的变化趋势相同。利用SPSS软件进行4因素3水平正交实验设计，在特定参数条件下，2种喷雾方式的因素影响排序相同，除尘效率为纤维栅数＞纤维丝间隙＞喉管气速＞喷雾量；系统阻力为喉管气速＞纤维栅数＞纤维丝间隙＞喷雾量；径向外喷最佳配置为喉管气速24 m/s、喷雾量2.3 L/min、2块间隙为0.8 mm纤维栅板；轴向喷雾为喉管气速28 m/s、喷雾量2.4 L/min、2块间隙为0.8 mm纤维栅板；在最优配置下的除尘性能为径向外喷＞轴向喷雾。     

国内外总量管理制度发展历程对南京市的启示

本文介绍了国内外总量管理制度的发展历程,特别是"十三五"以来我国总量管理工作新的规定,并由此产生的针对南京市主要污染物总量管理工作的几点启示。     

臭氧氧化—湿式钙法吸收工艺对烟气的同时脱硫脱硝

采用臭氧氧化—湿式钙法吸收工艺对模拟烟气进行同时脱硫脱硝处理。O₃于150 ℃下具有较高的热稳定性,可将NO氧化为高价态氮氧化物,且NO氧化率随n（O₃）∶n（NO）的增大而逐渐提高。烟气中SO₂和H₂O的存在对NO氧化率的影响不大。O₃对SO₂的氧化率较低,约为5%。3%（w）石灰石浆液对SO₂的吸收率接近100%,NO_x吸收率随n（O₃）∶n（NO）的增大而逐渐提高,当n（O₃）∶n（NO）为1.6时NO_x吸收率可达约65%。SO₂能促进吸收液对NO_x的脱除。石灰石浆液中加入0.2%（w）的（NH₄）₂SO₃或Na₂SO₃后NO_x吸收率可达约85%或82%,且吸收率随添加剂加入量的增加而提高,添加（NH₄）₂SO₃的NO_x吸收率略高于添加Na₂SO₃。     

快速城镇化地区生态系统服务的时空动态及权衡与协同分析——以苏锡常地区为例

苏锡常是我国经济飞速发展地区之一,也是重要的粮食生产基地.在快速城镇化背景下,该地区生态环境受到人类活动的强烈冲击,国土空间配置亟待优化.本研究基于多源数据,对苏锡常地区2000～2018年碳储存、食物供给、维持生物多样性3种生态系统服务的时空格局及演变特征进行刻画,并运用双变量空间自相关方法识别了生态系统服务之间的相互关系.结果 表明:(1)整体来看,2000～2018年,苏锡常地区的碳储存服务略有上升,食物供给服务和维持生物多样性服务波动下降;(2)苏锡常地区生态系统服务空间分布严重失衡,表现为中部建成区低,四周自然用地高的分布特点,城镇扩张区各类型生态系统服务退化较为严重;(3)在权衡与协同分析中,碳储存-食物供给服务、碳储存-维持生物多样性服务呈现协同关系,食物供给-维持生物多样性服务呈现权衡关系;(4)各项生态系统服务的权衡与协同关系存在空间差异,低值协同区集中分布在城市中心,高值协同区主要分布在西侧与南侧林地范围,低-高值与高-低值权衡区在空间上呈环绕相间分布.苏锡常地区在未来的发展中需要注意低值协同区和权衡区,有针对性地制定生态保护修复措施,合理调控社会经济发展,实现生态系统服务的协同增效.     

国产铝合金表面涂层体系在多因素综合加速试验条件下的老化规律研究

研究了一种国产新型铝合金表面防护体系在多因素协同加速试验条件下的表面性能变化规律。涂层在0.01 Hz处的阻抗模值由初始的1.88×10~9 Ω下降为2.04×10~7 Ω。经历5个周期的户内多因素综合加速试验的过程中,2A97铝合金表面涂层体系的防护效果呈持续下降趋势,但5周期后尚未完全失效。     

Soil surface Hg emission flux in coalfield in Wuda,Inner Mongolia,China

Hg emission flux from various land covers, such as forests, wetlands, and urban areas, have been investigated. China has the largest area of coalfield in the world, but data of Hg flux of coalfields, especially, those with coal fires, are seriously limited. In this study, Hg fluxes of a coalfield were measured using the dynamic flux chamber (DFC) method, coupled with a Lumex multifunctional Hg analyzer RA-915+ (Lumex Ltd., Russia). The results show that the Hg flux in Wuda coalfield ranged from 4 to 318 ng m^?2 h^?1, and the average value for different areas varied, e.g., coal-fire area 99 and 177 ng m^?2 h^?1; no coal-fire area 19 and 32 ng m^?2 h^?1; and backfilling area 53 ng m^?2 h^?1. Hg continued to be emitted from an underground coal seam, even if there were no phenomena, such as vents, cracks, and smog, of coal fire on the soil surface. This phenomenon occurred in all area types, i.e., coal-fire area, no coal-fire area, and backfilling area, which is universal in Wuda coalfield. Considering that many coalfields in northern China are similar to Wuda coalfield, they may be large sources of atmospheric Hg. The correlations of Hg emission flux with influence factors, such as sunlight intensity, soil surface temperature, and atmospheric Hg content, were also investigated for Wuda coalfield.

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Road traffic injuries among riders of electric bike/electric moped in southern China

Objective: Electric bike/moped-related road traffic injuries have become a burgeoning public health problem in China. The objective of this study was to identify the prevalence and potential risk factors of electric bike/moped-related road traffic injuries among electric bike/moped riders in southern China.

Methods: A cross-sectional study was used to interview 3,151 electric bike/moped riders in southern China. Electric bike/moped-related road traffic injuries that occurred from July 2014 to June 2015 were investigated. Data were collected by face-to-face interviews and analyzed between July 2015 and June 2017.

Results: The prevalence of electric bike/moped-related road traffic injuries among the investigated riders was 15.99%. Electric bike/moped-related road traffic injuries were significantly associated with category of electric bike (adjusted odds ratio [AOR] = 1.36, 95% confidence interval [CI], 1.01–1.82), self-reported confusion (AOR = 1.77, 95% CI, 1.13–2.78), history of crashes (AOR = 6.14, 95% CI, 4.68–8.07), running red lights (AOR = 3.57, 95% CI, 2.42–5.25), carrying children while riding (AOR = 1.96, 95% CI, 1.37–2.85), carrying adults while riding (AOR = 1.68, 95% CI, 1.23–2.28), riding in the motor lane (AOR = 2.42, 95% CI, 1.05–3.93), and riding in the wrong traffic direction (AOR = 1.63, 95% CI, 1.13–2.35). In over 77.58% of electric bike/moped-related road traffic crashes, riders were determined by the police to be responsible for the crash. Major crash-causing factors included violating traffic signals or signs, careless riding, speeding, and riding in the wrong lane.

Conclusion: Traffic safety related to electric bikes/moped is becoming more problematic with growing popularity compared with other 2-wheeled vehicles. Programs need to be developed to prevent electric bike/moped-related road traffic injuries in this emerging country.