基于RF-LSTM的鸡舍恶臭气体预测研究

以鸡舍氨气为研究对象,对鸡舍氨气预测模型进行了研究.首先,利用随机森林算法（RF）对影响鸡舍氨气浓度的环境变量进行重要性排序,选取温度、湿度、光照、气象温度、降雨量作为模型的输入变量;在此基础上,构建了基于长短时记忆神经网络（LSTM）的鸡舍氨气浓度预测模型,并将提出的预测模型应用于江苏省宜兴市某养鸡场的氨气浓度预测中,并与LSTM模型、RF-Elman模型和RF-BP模型进行了对比实验,结果表明,基于RF-LSTM模型的预测效果最好,其平均绝对误差（MAE）、平均绝对百分误差（MAPE）和均方根误差（RMSE）分别为0.9183、4.9637%和1.4262;同时,为了验证该模型的性能,本文还实现了不同时间尺度的鸡舍氨气浓度预测,提前2h、3h、4h、5h氨气预测的平均绝对误差（MAE）分别为1.6218、2.1991、2.8553和3.0677.本文提出的预测模型提高了鸡舍氨气浓度的预测精度,可为减少鸡舍恶臭气体排放提供科学依据.     

稻壳与聚氯乙烯共热解的特性及动力学

在热重分析仪中进行了稻壳和聚氯乙烯（PVC）的共热解实验,结果显示:在共热解时稻壳开始剧烈热解的温度相比单独热解时大幅度降低,由350℃降至300℃,表明掺入PVC降低了稻壳的热解温度。在升温速率为20℃/min,稻壳和PVC比例为2∶1（质量比）时,混合热解协同效应最明显。3种动力学分析方法均证明共热解现象的存在。利用Coats-Redfern法进行动力学分析,发现共热解活化能普遍较单独热解时低,表明PVC与稻壳共热解有明显的相互作用。利用Ozawa法进行分析,发现转化率为20%~60%阶段下共热解平均活化能值为37.60 kJ/mol,低于稻壳单独热解的平均活化能41.45 kJ/mol。Friedman法分析结果显示对应转化率下共热解活化能均低于稻壳单独热解活化能。稻壳和PVC共热解倾向于反应动力学控制。     

污泥生物炭去除水中重金属的研究进展

重金属带来的环境风险日益严峻,利用污泥生物炭去除水中重金属污染方面的研究得到了广泛关注。结合当前国内外研究现状,归纳了不同条件下制备的污泥生物炭对水中重金属,如Cd、Pb、Cr、As等的吸附机理,污泥生物炭对大多数重金属的吸附满足物理吸附和化学吸附的多重作用,可通过增加生物炭表面有效基团及有效吸附位点提升吸附性能。同时,总结了影响吸附效率的各种因素,探究了污泥生物炭的再生问题,并对今后污泥生物炭去除水中重金属的研究方向做出了展望。     

建筑垃圾堆放点样本集构建与优化研究

为更好地解决手工制作的建筑垃圾堆放点样本集效率低、数据量少,难以支撑基于深度学习的遥感图像目标检测算法训练需求的问题,采用基于像素的遥感分类方法构建建筑垃圾堆放点样本集,在此基础上结合直方图均衡化,CS-LBP算子约束以及迁移学习的方法对Wasserstein生成对抗模型（WGAN）进行优化,实现了样本集扩充。研究结果表明:相对于纯手工制作的样本集,基于像素的遥感分类方法可以显著提升样本集制作的效率;同时,经过WGAN优化后,生成样本模拟了原始数据的颜色与纹理特征分布规律,增加了原始数据的多样性,满足了扩充样本集的需求。     

中国工业园区绿色发展政策对比分析及对策研究

为了提升我国工业园区绿色发展水平,对目前我国工业园区发展历程、现状特征进行了分析,对工业园区绿色发展政策进行了梳理和对比,并结合工业园区绿色发展中存在的问题提出了对策建议.研究表明:①我国工业园区经历了快速发展、调整发展和科学发展等阶段,在经济发展、资源与能源优化利用、污染减排等方面成效显著.②我国工业园区绿色发展的相关政策主要体现在国家生态工业示范园区创建、园区循环化改造、国家低碳工业园区试点、绿色园区建设和UNIDO绿色工业园区创建等工作中,这些政策在推动主体、实施路径、侧重方向上各不相同又各有特色,对推动工业园区节能减排绩效明显.③目前,我国工业园区绿色发展存在的问题主要表现在重视程度有待提升、风险防范意识有待加强、创新能力有待提高等方面.为此,提出了我国工业园区绿色发展对策建议:积极践行绿色发展理念,推进园区绿色化、生态化、低碳化建设,实现经济环境双赢;注意环境风险防控,确保环境安全;创新管理机制,强化监督管理.      

Performance of different macrophytes in the decontamination of and electricity generation from swine wastewater via an integrated constructed wetland-microbial fuel cell process

Plants constitute a major element of constructed wetlands(CWs).In this study,a coupled system comprising an integrated vertical flow CW(IVCW) and a microbial fuel cell(MFC) for swine wastewater tre atment was developed to research the effects of macrophytes commonly employed in CWs,Canna indica,Acorus calamus,and Ipomoea aquatica,on decontamination and electricity production in the system.Because of the different root types and amounts of oxygen released by the roots,the rates of chemical oxygen demand(COD) and ammonium nitrogen(NH_4~+-N) removal from the swine wastewater differed as well.In the unplanted,Canna indica,Acorus calamus,and Ipomoea aquatica systems,the COD removal rates were 80.20%,88.07%,84.70%,and 82.20%,respectively,and the NH_4~+-N removal rates were 49.96%,75.02%,70.25%,and 68.47%,respectively.The decontamination capability of the Canna indica system was better than those of the other systems.The average output voltages were 520±42,715±20,660±27,and 752±26 mV for the unplanted,Canna indica,Acorus calamus,and Ipomoea aquatica systems,respectively,and the maximum power densities were 0.2230,0.4136,0.3614,and0.4964 W/m~3,respectively.Ipomoea aquatica had the largest effect on bioelectricity generation promotion.In addition,electrochemically active bacteria,Geobacter and Desulfuromonas,were detected in the anodic biofilm by high-throughput sequencing analysis,and Comamonas(Proteobacteria),which is widely found in MFCs,was also detected in the anodic biofilm.These results confirmed the important role of plants in IVCW-MFCs.     

Effects of SO2 and H2O on low-temperature NO conversion over F-V2O5-WO3/TiO2 catalysts

F-V_2 O_5-WO3/Ti02 catalysts were prepared by the impregnation method.As the content of F ions increased from 0.00 to 0.35 wt.%,the NO conversion of F-V_2 O_5-WO_3/TiO_2 catalysts initially increased and then decreased.The 0.2 F-V_2 O_5-WO_3/TiO_2 catalyst(0.2 wt.% F ion)exhibited the best denitration(De-NOx) performance,with more than 95% NO conversion in the temperature range 160-360℃,and 99.0% N2 selectivity between 110 and 280℃.The addition of an appropriate amount of F ions eroded the surface morphology of the catalyst and reduced its grain size,thus enhancing the NO conversion at low temperature as well as the sulfur and water resistance of the V_2 O_5-WO3/Ti02 catalyst.After selective catalytic reduction(SCR) reaction in a gas flow containing SO_2 and H_2 O,the number of NH3 adsorption sites,active component content,specific surface area and pore volume decreased to different degrees.Ammonium sulfate species deposited on the catalyst surface,which blocked part of the active sites and reduced the NO conversion performance of the catalyst.On-line thermal regeneration could not completely recover the catalyst activity,although it prolonged the cumulative life of the catalyst.In addition,a mechanism for the effects of S02 and H_2 O on catalyst NO conversion was proposed.     

Fast and efficient aqueous arsenic removal by functionalized MIL-100(Fe)/rGO/δ-MnO2 ternary composites: Adsorption performance and mechanism

Because of its significant toxicological effects on the environment and human health,arsenic(As) is a major global issue.In this study,an Fe-based metal-organic framework(MOF)(Materials of Institut Lavoisier:MIL-100(Fe)) which was impregnated with reduced graphene oxide(rGO) by using a simple hydrothermal method and coated with birnessitetype manganese oxide(δ-MnO_2) using the one-pot reaction process(MIL-100(Fe)/rGO/δ-MnO_2 nanocomposites) was synthesized and applied successfully in As removal.The removal efficiency was rapid,the equilibrium was achieved in 40 min and 120 min for As(Ⅲ) and As(Ⅴ),respectively,at a level of 5 mg/L.The maximum adsorption capacities of As(Ⅲ) and As(Ⅴ) at pH 2 were 192.67 mg/g and 162.07 mg/g,respectively.The adsorbent revealed high stability in pH range 2-9 and saturated adsorbent can be fully regenerated at least five runs.The adsorption process can be described by the pseudo-second-order kinetic model and Langmuir monolayer adsorption.The adsorption mechanisms consisted of electrostatic interaction,oxidation and inner sphere surface complexation.     

Algal toxicity induced by effluents from textile-dyeing wastewater treatment plants

This research aimed to evaluate the alga Scenedesmus obliquus toxicity induced by textiledyeing effluents(TDE).The toxicity indicator of TDE in alga at the physiological(algal growyth),biochemical(chlorophyll-a(Chl-a) synthesis and superoxide dismutase(SOD) activity) and structural(cell membrane integrity) level were investigated.Then we further study the relationship among toxicity indicators at physiological and biochemical level,and supplemented by research on algal biomacromolecules.According to the analysis of various endpoints of the alga,the general sensitivity sequence of toxicity endpoints of Scenedesmus obliquus was:SOD activity Chl-a synthesis algal growth.The stimulation rate of SOD activity increased from day 3(57.25%～83.02%) to day 6(57.25%～103.81%),and then decreased on day 15(-4.23%～-32.96%),which indicated that the antioxidant balance system of the algal cells was destroyed.The rate of Chl-a synthesis inhibition increased gradually,reaching19.70%～79.39% on day 15,while the rate of growth inhibition increased from day 3(-12.90%～10.16%) to day 15(-21.27%～72.46%).Moreover,the algal growth inhibition rate was positively correlated with the inhibition rate of SOD activity or Chl-a synthesis,with the correlation coefficients were 0.6713 and 0.5217,respectively.Algal cells would be stimulating to produce excessive reactive oxygen species,which would cause peroxidation in the cells,thereby destroying chloroplasts,inhibiting chlorophyll synthesis and reducing photosynthesis.With increasing exposure time,irreversible damage to algae can lead to death.This study is expected to enhance our understanding of the ecological risks through algal tests caused by TDE.