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Xu Xiangyu Wei Jianping Wang Mengyuan Jiang Wan Wen Zhihui Liu Yong 《Environmental science and pollution research international》2022,29(55):83304-83320
Environmental Science and Pollution Research - The migration law of dust in the roadway is the basis of dust control, but most of the relevant studies are based on the horizontal roadway, ignoring... 相似文献
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快速城镇化会加剧地表水体氮磷营养盐的富集,引起水体富营养化问题. 研究城镇分布对河流与湖库氮磷污染特征的影响,分析其污染热点与来源具有重要意义. 于2020年7月—2021年7月调查了新安江水系及千岛湖水体氮磷污染的时空变化特征,分析了水质与土地利用类型的关系,揭示了千岛湖水体氮磷污染的来源. 结果表明:①时间上,新安江水系氮磷浓度季节性变化差异明显. TN浓度表现为冬季枯水期〔(1.96±1.24) mg/L〕>主汛期〔(1.63±0.71) mg/L〕>春汛期〔(1.42±0.49) mg/L〕,TP浓度表现为主汛期〔(0.101±0.049) mg/L〕>冬季枯水期〔(0.067±0.068) mg/L〕>春汛期〔(0.06±0.033) mg/L〕,汛期氮、磷浓度分别是非汛期的1.6和2.4倍. ②空间上,城镇污染对水体营养盐浓度影响显著. 水体流经人口集中、城镇化程度高的屯溪区后,TN、TP、NH4+-N浓度平均增幅分别为86.1%、77.7%和164.4%,干流水体受纳歙县城镇三大支流来水后,TN、TP浓度平均增幅分别为47.6%、70.3%. ③ Spearman相关分析结果表明,5 km缓冲区耕地和建筑用地面积占比与氮磷营养盐各形态浓度之间均存在显著正相关关系,其中建筑用地面积占比对NH4+-N浓度影响较大(R=0.323,P<0.001),耕地面积占比对NO3?-N影响相对较大(R=0.265,P<0.05). 研究显示,城镇面源污染是新安江水系氮磷污染的主要来源,降雨径流是水体磷富集的主要驱动力,枯水期城镇污染对水体氮浓度的影响较大,在千岛湖营养盐控制中应尤为关注上游城镇污染管控. 相似文献
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Bin Liang Deyong Kong Mengyuan Qi Hui Yun Zhiling Li Ke Shi E Chen Alisa S. Vangnai Aijie Wang 《Frontiers of Environmental Science & Engineering》2019,13(6):84
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Yufeng Liao Mengmeng Tang Mengyuan Li Peng Shi Aimin Li Yangyang Zhang Yang Pan 《Frontiers of Environmental Science & Engineering》2023,17(10):125
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方便面6种真菌毒素的监测分析 总被引:1,自引:0,他引:1
为监测并了解方便面中6种真菌毒素的污染状况,样品经乙腈甲酸水溶液提取,采用高液相色谱-串联质谱多反应监测负离子模式进行检测,内标法定量,依据食品安全国家标准-食品中真菌毒素限量进行判断.6种真菌毒素在0.2—400μg·L~(-1)范围内有较好的线性关系(r0.99),回收率为87.6%—101.3%,相对标准偏差为1.1%—3.7%.玉米赤霉烯酮、赭曲霉毒素及脱氧雪腐镰刀菌烯醇检出率分别为27.3%、51.5%及90.9%,超标率分别为3.0%、12.1%及3.0%,其余3种毒素均未检出. 相似文献
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Feng Zhao Xu Zhan Hai Xu Guangwei Zhu Wei Zou Mengyuan Zhu Lijuan Kang Yulong Guo Xingchen Zhao Zicong Wang Wei Tang 《环境科学学报(英文版)》2022,34(1):229-239
Eutrophication and harmful cyanobacterial blooms threaten water resources all over the world. There is a great controversy about controlling only phosphorus or controlling both nitrogen and phosphorus in the management of lake eutrophication. The primary argument against the dual nutrients control of eutrophication is that nitrogen fixation can compensate the nitrogen deficits. Thus, it is of great necessary to study the factors that can significantly affect the nitrogen fixation. Due to the dif... 相似文献
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Mengyuan Zhu Guangwei Zhu Linlin Zhao Xin Yao Yunlin Zhang Guang Gao Boqiang Qin 《Environmental science and pollution research international》2013,20(3):1803-1811
Algal bloom could drastically influence the nutrient cycling in lakes. To understand how the internal nutrient release responds to algal bloom decay, water and sediment columns were sampled at 22 sites from four distinct regions of China’s eutrophic Lake Taihu and incubated in the laboratory to examine the influence of massive algal bloom decay on nutrient release from sediment. The column experiment involved three treatments: (1) water and sediment (WS); (2) water and algal bloom (WA); and (3) water, sediment, and algal bloom (WSA). Concentrations of dissolved oxygen (DO), total nitrogen (TN), total phosphorus (TP), ammonium (NH 4 + -N), and orthophosphate (PO 4 3? -P) were recorded during incubation. The decay of algal material caused a more rapid decrease in DO than in the algae-free controls and led to significant increases in NH 4 + -N and PO 4 3? -P in the water. The presence of algae during the incubation had a regionally variable effect on sediment nutrient profiles. In the absence of decaying algae (treatment WS), sediment nutrient concentrations decreased during the incubation. In the presence of blooms (WSA), sediments from the river mouth released P to the overlying water, while sediments from other regions absorbed surplus P from the water. This experiment showed that large-scale algal decay will dramatically affect nutrient cycling at the sediment–water interface and would potentially transfer the function of sediment as “container” or “supplier” in Taihu, although oxygen exchange with atmosphere in lake water was stronger than in columns. The magnitude of the effect depends on the physical–chemical character of the sediments. 相似文献
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为有效评估装配式建筑吊装施工中的安全风险状态,识别关键风险因素,运用系统理论过程分析方法(STPA)构建吊装施工过程中的控制反馈结构,识别导致危险的不安全控制行为,确定不安全控制行为的致因因素;基于风险因素间的关联关系构建贝叶斯网络(BN)模型,推理计算装配式建筑吊装施工安全风险状态概率,并结合反向诊断推理分析影响安全事故的风险因素;通过敏感性分析,识别装配式建筑吊装施工安全中的关键风险因素。结果表明:装配式建筑吊装施工安全风险处于低风险状态;起重机械超负荷运行、现场安全管理不到位和吊索吊具存在缺陷等因素是影响装配式建筑吊装施工安全风险的关键风险因素。 相似文献
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湿地是陆地生态系统重要的脱氮热点,其对削减流域面源氮负荷具有重要意义. 为探究水库流域沟渠、池塘等湿地的脱氮速率及其影响因素,分别于2021年春季(3月)与夏季(6月)采集了天目湖沙河水库流域内典型土地利用类型下沟塘湿地的原状泥-水柱,利用同位素示踪技术进行室内流动培养,测定了不同沟塘湿地的反硝化速率和厌氧氨氧化速率. 结果表明:①各沟塘湿地沉积物均具有较高的脱氮速率,春季脱氮速率范围为10.59~107.65 μmol/(m2·h),平均值为70.73 μmol/(m2·h),夏季脱氮速率范围为32.07~150.10 μmol/(m2·h),平均值为112.36 μmol/(m2·h),春季果园排水沟渠的脱氮速率最高,夏季茶园退水池塘的脱氮速率最高. ②春季和夏季不同沟塘湿地厌氧氨氧化作用对脱氮的贡献率(简称“厌氧氨氧化贡献率”)平均值分别为45.45%、36.26%,其中生活污水排放池塘和茶园退水池塘的厌氧氨氧化贡献率在夏季分别下降26.82%、14.98%,春季和夏季果园排水沟渠和入湖口河流湿地的厌氧氨氧化贡献率变化不大,平均值分别为21.17%、48.99%. ③统计分析表明,水体溶解性无机氮(DIN)浓度和沉积物有机碳含量与沉积物脱氮速率均呈显著相关,且高温与低溶解氧浓度条件下也有利于脱氮作用的进行. 研究显示,水库流域沟塘湿地具有较好的脱氮能力,通过有效调控管理能够大大增加流域氮的截留能力,对水库水质保障具有重要作用. 相似文献