Determinants of waste characterization in Lebanon and material recovery potential

Journal of Material Cycles and Waste Management - Waste represents a largely untapped source of raw material in many countries, as resource recovery rates remain generally low despite most of the...     

Correction: Insight into the Adsorption Properties of Chitosan/Zeolite‑A Hybrid Structure for Effective Decontamination of Toxic Cd (II) and As (V) Ions from the Aqueous Environments

Journal of Polymers and the Environment -     

Evolutionary processes and sources of high-nitrate haze episodes over Beijing, Spring

Rare and consecutive high-nitrate haze pollution episodes were observed in Beijing in spring2012. We present detailed characterization of the sources and evolutionary mechanisms of this haze pollution, and focus on an episode that occurred between 15 and 26 April. Submicron aerosol species were found to be substantially elevated during haze episodes, and nitrates showed the largest increase and occupation(average: 32.2%) in non-refractory submicron particles(NR-PM_1), which did not occur in other seasons as previously reported. The haze episode(HE) was divided into three sub-episodes, HEa, HEb, and HEc. During HEa and HEc, a shallow boundary layer, stagnant meteorological conditions, and high humidity favored the formation of high-nitrate concentrations, which were mainly produced by three different processes —daytime photochemical production, gas-particle partitioning, and nighttime heterogeneous reactions — and the decline in visibility was mainly induced by NR-PM_1.However, unlike HEa and HEc, during HEb, the contribution of high nitrates was partly from the transport of haze from the southeast of Beijing — the transport pathway was observed at ~800–1000 m by aerosol Lidar —and the decline in visibility during HEb was primarily caused by PM_(2.5). Our results provide useful information for air quality improvement strategies in Beijing during Spring.     

土壤中多环芳烃微生物降解能力模拟

为了揭示微生物菌种(组合)对土壤中PAHs(多环芳烃)降解率的影响以及不同类型PAHs抗微生物降解能力的差异,分析了北京市6个不同环境功能区土壤中微生物种类及其分布特征,从中筛选出部分微生物菌种对典型PAHs和原油进行降解模拟试验,对比分析微生物对不同PAHs降解能力的差异.结果表明:① 不同菌种组合对PAHs的降解能力存在明显差异,与假单胞菌属、无色杆菌、短稳杆菌混合菌相比,假单胞菌属、无色杆菌、短稳杆菌和微杆菌混合菌对PAHs的降解率高0.6%~4.5%;② 在相同降解条件下,不同PAHs的降解率存在明显差异,在单体培养基中,LMW PAHs(低环数PAHs)的降解率在25.3%以上,而HMW PAHs(高环数PAHs)的降解率都小于20.1%;③ 在单体培养基与混合培养基中PAHs的降解能力也存在一定差别,单体培养基中PAHs的降解率较混合培养基中高4.2%~26.6%;④ 无论在单体培养基中,还是混合培养基中这些化合物的降解率均存在随着降解时间的增加而增大的现象;⑤ 在原油培养基中不同PAHs的降解率更为复杂,并且出现了中低分子量PAHs降解率随降解时间增加反而降低的假象,这可能是由于随着时间增加,微生物对PAHs的降解能力加强,原油中含烷基的PAHs基团降解或HMW PAHs被微生物降解产生LMW PAHs中间产物造成.研究显示,假单胞菌属、无色杆菌、短稳杆菌和微杆菌对HMW PAHs和LMW PAHs均有明显的降解效果,但不同PAHs的降解率存在明显的差异,即使是同一单体化合物,在单体培养基、混合培养基和原油培养基三种不同的降解条件下,其降解率也具有不同程度的差别.      

粮食真菌毒素的生殖、发育与遗传毒性:现状与展望

粮食及其制品会受到多种真菌毒素的污染。粮食真菌毒素现已被证实具有多种毒性作用,如细胞毒性、发育毒性、生殖毒性、免疫毒性和遗传毒性等,严重危害人和动物健康,甚至还会对间接或未接触毒素的子代产生不良影响,但目前有关继代毒理学数据极为缺乏。本文主要阐述了粮食中常见真菌毒素对亲本世代及其子代生殖系统/能力和生长发育的影响,简述了不同毒素诱导生殖发育毒性的作用机理并提出展望,旨在全面了解粮食真菌毒素的生殖发育及遗传毒性作用,为进一步开展粮食真菌毒素的健康风险评估,合理制定相关限量标准与法规,指导公共卫生健康并开展主动防治与干预提供重要理论依据。     

How can sports entrepreneurs achieve their corporate sustainable development goals under the COVID-19 epidemic?

Environmental Science and Pollution Research - The present study aimed to explore the opportunities for the sustainable development of professional sports enterprises and events from the...     

Dynamic pollution emission prediction method of a combined heat and power system based on the hybrid CNN-LSTM model and attention mechanism

Environmental Science and Pollution Research - Combined thermal power (CHP) production mode plays a more important role in energy production, but the impact of its pollutant emission on the natural...     

福建省水田土壤有机碳积累对未来温度升高的响应

明确未来温度升高下我国农田土壤的碳“源-汇”效应是合理制定碳中和管理政策的基础.以我国典型亚热带地区——整个福建省84个县(市、区)水田土壤为研究对象,基于目前该区域最详细的1∶5万大比例尺土壤数据库和生物地球化学过程模型(DNDC),模拟了2017～2053年不同温度升高情景下全省水田土壤的有机碳动态变化.结果表明,在常规温度(对照)以及温度上升2、4和6℃这4种情景分析下,福建省水田土壤的固碳总量分别为11.56、9.44、7.08和4.91 Tg,年均固碳速率(以C计)分别为173、141、106和74 kg·(hm²·a)^-1,说明随着未来温度升高固碳速率在下降,但总体而言在6℃升温下全省水田土壤仍是“碳汇”.从不同土壤类型来看,潜育水稻土受气温升高的影响最大,不同处理下固碳速率降幅介于20%～69%之间,而盐渍水稻土受气温升高的影响最小,不同处理下固碳速率降幅介于14%～43%之间.从不同行政区来看,受气温升高影响最大的是位于武夷山脉附近的三明市,不同处理下固碳速率降幅介于27%～83%之间,而受气温升高影响最小的是沿海的泉州市和莆...     

可见光激发下模拟海水中四环素光降解的机制和路径

为了探明海水体系中多相光催化降解污染物的机制和路径,研究了在可见光激发下不同介孔TiO₂光催化降解纯水和模拟海水中四环素(TC)的过程,明确了不同盐离子对光催化降解过程的影响.结合自由基捕获实验,电子自旋共振(ESR)光谱和中间产物分析研究了光降解污染物的主要活性物种和模拟海水中TC降解途径.结果表明,模拟海水中TC光催化过程会受到显著抑制,手性介孔TiO₂催化剂对TC光降解反应速率相比其在纯水体系降低了70%左右,而非手性TiO₂光催化剂在海水体系中几乎不能降解TC.模拟海水中阴离子对光降解过程影响较小,但Mg²⁺和Ca²⁺存在会显著抑制光催化过程.无论在纯水还是模拟海水中,可见光激发后催化剂产生的活性物种都是空穴为主,因此模拟海水中降解路径与纯水体系中相同.盐离子不会抑制活性物种的产生,但Mg²⁺和Ca²⁺会富集在TC分子中电负性强的原子周边,阻碍空穴等对TC分子中电负性强原子的攻击,从而抑制了光催化降解效率.     

基于ENSO发展过程的中国夏季降水时空变化特征

利用1961—2019年中国地面降水月值格点数据,结合趋势分析、合成分析及T检验等气候诊断方法,对中国夏季降水时空变化特征进行分析,进而探讨不同类型ENSO事件对应夏季降水规律。结果表明：20世纪60—90年代末,长江、淮河夏季降水波动增加,海河降水持续下降,符合“南涝北旱”空间特征;21世纪后,除淮河夏季降水下降之外,其他流域降水均呈增加趋势;对于不同ENSO发展类型而言,以厄尔尼诺为主导的事件,副高脊线西伸增强,中国夏季多雨区集中在江淮地区,由南向北呈现“中间涝,南北旱”的空间格局;以拉尼娜为主导的事件中,副高脊线东移、控制面积缩小,中国夏季降水在胡焕庸线两侧、华南降水明显偏少;对于两种转换型事件而言,当前冬发生厄尔尼诺、夏季转为拉尼娜时,副高西伸且面积扩大,中国夏季降水偏多;反之,副高东移且面积缩小,中国夏季降水整体偏少。