| 1 | 基于遗传算法的全光谱LED植物光源阵列优化研究显示文摘为解决全光谱LED发光具有一定的光束发散角,易造成植物在培育过程中光量子通量密度分布不均匀的问题,提出基于遗传算法对随机分布全光谱LED植物光源阵列进行优化设计,仿真对比三角光源阵列与传统矩形光源阵列的光量子通量密度PPFD均匀度。首先通过理论推导全光谱LED光照度与PPFD之间的换算关系式,计算换算系数,用目标平面上光照度的均匀性间接表征PPFD的均匀性,并以光照度函数的标准差构建评价函数,作为遗传算法的适应度函数。根据算法寻优结果,绘制LED阵列三维模型导入Tracepro中仿真模拟验证。结果表明:三角与矩形阵列的PPFD均匀度均超过了85%,且三角光源阵列的PPFD均匀度与光照分布特性均优于矩形光源阵列,验证了算法的可行性,同时提高了全光谱LED光源阵列的设计效率。 | 林孝腾 Mulowayi Mutombo Arcel 梅方炜 郑书河 | 2020 | 中国农机化学报2020，41，8： | 2 |
| 8 | Assessment of Trace Metal Levels of Groundwater in Lubumbashi,Kampemba and Kamalondo Communes of Lubumbashi City,Democratic Republic of Congo显示文摘Trace metal levels of groundwater in Lubumbashi,Kampemba and Kamalondo communes of Lubumbashi city were assessed from October 2016 to February 2017.Two hundred forty water samples collected from twenty-two spade-sunk wells and twelve drilled wells in these three communes of Lubumbashi city were analyzed for their metal contents using ICP-SF-MS(Inductively Coupled Plasma-Sector Field Mass Spectrometry).Twenty trace elements including strontium,molybdenum,cadmium,cesium,barium,tungsten,thallium,lead,bismuth,uranium,aluminum,vanadium,chromium,manganese,iron,cobalt,nickel,copper,zinc and arsenic were recorded at varying concentrations in all the water samples and were compared with the WHO(World Health Organization),US EPA(Environmental Protection Agency)and EU(European Union)drinking water MCLs(Maximum Concentration Limits)for cadmium,barium,thallium,lead,uranium,aluminum,chromium,manganese,iron,nickel,copper,zinc and arsenic.Mean cadmium,lead,aluminum,manganese,iron,nickel,zinc and arsenic levels respectively exceeded the WHO,US EPA and EU drinking water MCLs in 6.66%,3.38%,26.67%,5.02%,30.03%,3.38%,1.64% and 5.02% of the samples with the highest mean levels of 116.89μg/L for cadmium,38.162μg/L for lead,2,712.5μg/L for aluminum,1,242.68μg/L for manganese,17,325.98μg/L for iron,64.647μg/L for nickel,9,900.72μg/L for zinc and 65.458μg/L for arsenic.Mean water pH values ranged from 4.7 to 11.1 with 19.17% of the groundwater samples having mean pH values outside the WHO drinking water pH optimum range values of 6.5-8.5,including 5.02% of the water samples which were acidic(mean pH values ranging from 4.7 to 6.4)and 14.15% which were alkaline(mean pH values ranging from 8.6 to 11.1).With such physicochemical and trace metal contamination status of groundwater in the three communes of Lubumbashi city,there is a high risk to the health of people who use that water to meet their drinking water needs. | Bamba Bukengu Muhaya Sonia Catherine Mulongo Clarisse Zoza Kunyonga Alexis Woot Mpomanga Emery Mutombo Kalonda | 2021 | Journal of Environmental Science and Engineering(A)2021，10，1： | 0 |
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