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151.
152.
Zhenhao Ling Liqing Wu Yonghong Wang Min Shao Xuemei Wang Weiwen Huang 《环境科学学报(英文版)》2022,34(4):259-285
Secondary organic aerosol(SOA) is a very important component of fine particulate matter(PM2.5) in the atmosphere. However, the simulations of SOA, which could help to elucidate the detailed mechanism of SOA formation and quantify the roles of various precursors, remains unsatisfactory, as SOA levels are frequently underestimated. It has been found that the performance of SOA formation models can be significantly improved by incorporating the emission and evolution of semivolatile and ... 相似文献
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154.
This study investigated that water washing effects on the metals emission reduction in melting of municipal solid waste incinerator (MSWI) fly ash. Experimental conditions were conducted at liquid-to-solid (L/S) ratio 10, 20, and 100 for water-washing process and its subsequent melting treatment at 1450 °C for 2 h. The simple water-washing process as a pre-treatment for MSWI fly ash can remove most of the chlorides, leachable salts, and amphoteric heavy metals from the MSWI fly ash, resulting in the washed ash having lowered chlorine content. MSWI fly ashes washed by L/S ratio 10 and above that were melted at 1450 °C produced slag containing relatively high vitrificaton ratio of Cu and Pb. Besides, the vitrification ratios of Na, K, Ca, and Mg in washed MSWI fly ash were also higher than that of MSWI fly ash. The results indicated that washed MSWI fly ash can reduce the emission of metallic chlorides during its subsequent melting treatment. 相似文献
155.
选择北京市四家锅炉厂的电焊工56名,即从事手把焊、氩弧焊、CO2气体保护焊、电弧气爆等特种工种作业人员。通过调查,提出单项四级评分标准,再依模糊数学模型,进行综合评价。按B=A·R,求得B中最大元为0.707。最后总评为甲级。此结果与权数分配有关。此方法,可为劳动卫生管理(防护措施评级)提供依据。 相似文献
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157.
根据毕节地区16个主要造林树种的生态生物学特性,结合本区气候和土壤生态条件,运用 Fuzzy 二级评价模型,对各土类水土保持树种的适宜程度进行了综合评价。 相似文献
158.
Characteristics of bricks made from waste steel slag 总被引:4,自引:0,他引:4
The characteristics of bricks made from steel slag were investigated in this research. Slag addition was shown to reduce the required firing temperature. When the firing temperature was greater than 1050 degrees C and the slag addition less than 10%, the bricks met ROC national standard CNS 3319 third-class brick for builders. The percentage of slag increased as the quartz and kaolin decreased in the sintered samples while the magnesium aluminum silicate and calcium silicate increased. There were no new crystal phases observed in these samples. 相似文献
159.
Chiang Hung-Lung Huang Yao-Sheng 《Atmospheric environment (Oxford, England : 1994)》2009,43(26):4014-4022
Particulate matter, including coarse particles (PM2.5–10, aerodynamic diameter of particle between 2.5 and 10 μm) and fine particles (PM2.5, aerodynamic diameter of particle lower than 2.5 μm) and their compositions, including elemental carbon, organic carbon, and 11 water-soluble ionic species, and elements, were measured in a tunnel study. A comparison of the six-hour average of light-duty vehicle (LDV) flow of the two sampling periods showed that the peak hours over the weekend were higher than those on weekdays. However, the flow of heavy-duty vehicles (HDVs) on the weekdays was significant higher than that during the weekend in this study. EC and OC content were 49% for PM2.5–10 and 47% for PM2.5 in the tunnel center. EC content was higher than OC content in PM2.5–10, but EC was about 2.3 times OC for PM2.5. Sulfate, nitrate, ammonium were the main species for PM2.5–10 and PM2.5. The element contents of Na, Al, Ca, Fe and K were over 0.8 μg m?3 in PM2.5–10 and PM2.5. In addition, the concentrations of S, Ba, Pb, and Zn were higher than 0.1 μg m?3 for PM2.5–10 and PM2.5. The emission factors of PM2.5–10 and PM2.5 were 18 ± 6.5 and 39 ± 11 mg km?1-vehicle, respectively. The emission factors of EC/OC were 3.6/2.7 mg km?1-vehicle for PM2.5–10 and 15/4.7 mg km?1-vehicle for PM2.5 Furthermore, the emission factors of water-soluble ions were 0.028(Mg2+)–0.81(SO42?) and 0.027(NO2?)–0.97(SO42?) mg km?1-vehicle for PM2.5–10 and PM2.5, respectively. Elemental emission factors were 0.003(V)–1.6(Fe) and 0.001(Cd)–1.05(Na) mg km?1-vehicle for PM2.5–10 and PM2.5, respectively. 相似文献
160.
Lijuan Sun Cuixia Guo Ling Yao Tiejuan Zhang Jingjing Wang Li Wang Yan Liu Keyang Wang Longxia Wang Qingqing Wu 《黑龙江环境通报》2019,39(12):1086-1095