盐沼枯落物碳氮和有色溶解有机物淋溶过程研究

盐沼枯落物的短期淋溶过程对东滩沿岸的水质有重要影响.采用东滩3种典型盐沼植物的茎和叶的枯落物为材料进行为期48h的室内浸泡模拟实验.利用有机碳探测分析仪测定不同时间的可溶性有机碳(DOC)和总可溶性氮(TDN)浓度然后转换为累积释放量,通过紫外可见光光谱参数表征有色溶解有机物(CDOM)浓度,结合三维荧光光谱(EEMs)和平行因子(PARAFAC)分析推断CDOM的荧光组分的变化特征.结果 表明在淋溶释放的最初48 h,DOC、TDN、CDOM、两个类腐殖质荧光组分和两个类蛋白荧光组分的释放过程呈对数曲线状,最初8h增长迅速,8～48 h则增幅减缓或出现小幅下降趋势.不同种类的植物以及同种植物的不同部位的初始基质对枯落物的DOC和TDN释放量有显著影响.TDN最大累积释放量与初始基质有机碳和氮含量呈显著的正相关.枯物体中的氮比有机碳更容易淋失.各个荧光组分的贡献率变化不大,但不同植物种类之间存在显著差异,由此可以推断枯落物的初期淋溶以物理性过程为主.我们的研究结果表明,盐沼枯落物的淋溶对潮滩水水质有着显著的影响.     

Application of plant carbon source for denitrification by constructed wetland and bioreactor: review of recent development

Water quality standard for nitrate becomes more and more strict, and the plant carbon source is widely used for denitrification by constructed wetland (CW) and bioreactor. However, the nitrate removal efficiency by different types of plant carbon source are not evaluated comprehensively. Denitrification performance of different plant carbon sources, and the influence of dosing method and pretreatment are thoroughly reviewed in this paper, which aims to investigate the accurate utilization of plant carbon source for nitrogen (as nitrate) removal. It is concluded that plant carbon source addition for all types of CWs and bioreactors can improve the nitrate removal efficiency to some extent, and the dosing method of plant carbon source for denitrification should be further studied and optimized in the future. The popular carbon sources for CW and bioreactor denitrification enhancement are woodchip, chopped macrophytes, crop plants, macrophytes litters, etc. The recommended optimum C:N ratios for CW and bioreactor are 4.0:5.0 and 1.8:3.0, respectively. The physical and biological pretreatments are selected to supply organic carbon for long-term denitrification.     

Effect of alkali catalyst on biodiesel production in South Korea from mixtures of fresh soybean oil and waste cooking oil

Biodiesel from waste cooking oil (WCO) and soybean oil (SO) mixture was produced by changing the alkali catalyst (NaOH) content and the WCO to SO ratio in the feedstock. All the prepared biodiesel samples satisfied the standard requirement in terms of free glycerol, density, and acid value. The minimum catalyst content and the highest WCO composition to get biodiesel from the WCO/SO mixture feedstock without ruining the biodiesel properties were 1.0 and 60 wt %, respectively. This conclusion implies that the waste cooking oil mixture, which contains 40 wt % fresh soybean oil, could be treated like the fresh soybean oil to produce biodiesel, and that this behavior would be helpful to reduce the biodiesel production cost when waste cooking oil used as feedstock. The unsaturated methyl esters such as linoleic, and oleic acid were dominant (almost 80 % w/w) in the fresh soybean oil. However the saturated methyl ester was increased due to the double bond breaking during the frying process. These results may deteriorate the biodiesel quality by changing the methyl ester composition.     

Spatial Organization Mechanism of Aircraft Manufacturing

Unquestionably, aircraft industry plays an important part in both economy and security of a nation. However, few of articles have dealt with the spatial development of this industry sector. The purpose of this article is to analyze the dynamics of agglomeration and diffusion of aircraft industry.In a historical view, with some spatial analysis methods, this research discusses the characteristics and patterns of aircraft industry's spatial organization and evolution, globally, nationally and regionally respectively. We find out there is a 'Matthew effect' in aircraft industry of the world, and the spatial evolution of the industry is consistent with the nation's industrialization process. Then, it concludes that the main agglomeration forces consist of capital, talents, technology and cluster's advantages, and the main diffusion forces include comparative advantages, cost and risk sharing, emerging markets, development policy for backward regions and military requirements. All the factors can be divided into market forces making the spatial development of aircraft industry normal and non-market forces making that irregular. In particular, lessons from the USA and France are expected to be conducive to the rise of China's aircraft industry in the future.     

冬季减排对广东省空气污染的影响分析

使用WRF-SMOKE-CAMx模型模拟了2017年1月广东省各市的主要大气污染物,模型对SO 2,O 3,PM 10和PM 2.5的模拟效果较好,但对NO 2存在低估,目前的排放源清单可能普遍低估了NO x的排放量。与基准年2015年相比,预测2020年广东省人为源的SO 2,NO 2,CO,PM 10,PM 2.5,VOCs,NH 3排放分别下降40%,32%,37%,23%,25%,31%,18%。在气象场与2017年1月一致的假设下,2020年同期广东省各市平均NO,NO 2,SO 2,PM 10,PM 2.5月均值下降率分别为31%,19%,17%,14%,14%。O 3平均浓度出现反弹,涨幅均值为11%,主要是由NO滴定效应减弱导致,显示了广东省臭氧污染防治的难度。不同地区气态污染物浓度变化率存在较大差异,2020年冬季珠三角地区的臭氧浓度上升显著,粤东与粤北的上升幅度相对较低;各市气溶胶的变化率相对较接近。     

调蓄池在区域水系生态治理中的应用

在串湖流域黑臭水体污染治理过程中,调蓄池起到了合流污水截流及初期雨水面源污染控制的作用。本工程根据汇水分区的划分,共设置11座调蓄池,总调蓄容积为130500m^3。调蓄池的设置可最大限度地消减排入河道的污染物,同时对于控制初期雨水带来的面源污染至关重要。     

石油石化应急管理工作的问卷调查与讨论

为分析石油石化企业应急管理工作中存在的矛盾问题,选取有代表性的24家企业作为调查对象,通过随机抽样方法选定620名员工的样本容量,设置企业应急管理中涉及的应急培训、应急处置卡、应急准备、应急资源等4方面15项代表性问题作为问卷调查内容;根据调查问卷结果及分析,提出企业在应急培训、处置、准备方面的薄弱环节以及不同企业和领导层间在应急管理中的差异性;根据分析结果,提出相关措施建议,为后续应急管理工作的改进完善提供决策支持。     

臭氧洗消化学战剂模拟剂DPCP试验研究

用臭氧对神经性化学战剂的模拟剂氯磷酸二苯酯（DPCP）进行洗消,试验考察了初始酸度、O₂流量、放电功率、放电室压力、反应温度、初始浓度和O₃流量等因素对DPCP降解率的影响。碱性条件下DPCP降解率高于酸性条件下的降解率;反应温度、O₃流量、放电功率的增加,DPCP降解率上升;初始浓度增加,DPCP降解率下降;氧气流量和放电室压力增加,DPCP降解率先上升,后下降。在最佳反应条件下,50 mg/L的DPCP处理16 min降解率达到98%,矿化率40.1%。     

古尔班通古特沙漠边缘生态环境建设策略

沙漠古已有之,近期由于开发的需要,人为造成的沙漠扩张明显超过历史时期,沙漠化与人类干扰的加剧有直接关系。在荒漠区的开发及其生态环境建设过程中,应深入了解荒漠区的环境现状,充分利用该区的自然环境条件,改造沙漠,实施保护、利用与建设相结合的方针,以荒漠植被自然侵移规律为依据,依靠自然降水,以最大限度人工发展可供饲用的灌林,实现荒漠生态环境建设的目的     

深圳大气污染特征模拟及环境容量估算

本文根据深圳市8 个监测站点2013 年的逐日PM₁₀ 和PM_2.5 浓度监测数据、气象数据,统计风向、风速、稳定度联合频率等,利用污染物在大气中输送扩散模式,由实测的浓度值反推出污染物的产生量或排放量的方法,重点分析龙华新区PM₁₀ 和PM_2.5 的污染特征,并依据环境目标值,估算该区域剩余环境容量。研究结果表明,龙华新区全年盛行东风、南风,其风频分别为16.7%、13.2%,风速约为1.6m/s,PM₁₀、PM_2.5 浓度均呈现出季节性变化,秋、冬季浓度值较高,尤其在10 月到次年1 月份,其排放强度主要受本地污染源的影响。除此以外,其西、北部的污染源对其污染物浓度有一定的影响。新区PM₁₀ 和PM_2.5 的剩余环境容量均呈现负值,尤其以PM_2.5 最为突出,须大力加强减排控制,以达到环境目标值