环境经济综合核算的环境资源价值问题的研究

随着人类社会经济的发展,环境污染日益严重以及环境资源的日趋短缺问题的出现,环境资源也逐渐显示出其稀缺性。在环境经济综合核算体系中,环境资源价值估算是环境核算的核心问题。环境资源价值问题的研究对资源管理、生态建设和环境保护具有重要的理论和现实意义。通过查阅国内外文献,探讨环境资源价值的研究现状、理论及其评估方法。在总结现有的环境资源价值评估方法的基础上,提出了应用能值分析方法来客观核算环境资源价值,从而能够更接近环境资源的真实价值。     

Flocculation behaviors of a novel papermaking sludge-based flocculant in practical printing and dyeing wastewater treatment

•PSBF performed better than PAC and PAM in CODCr removals. •PSBF was more insensitive to changing pH than PAC and PAM. •PAC could remove humic acid-like pollutants and dye particles. •PSBF was efficient in removing tryptophan-like pollutants from PPDW. •A secondary coagulation-flocculation process (PAC→PSBF) is proposed here. In our previous studies, several papermaking sludge-based flocculants (PSBFs) were synthesized from wood pulp papermaking sludge. The structure-activity relationships of the PSBFs have been investigated in simulated dye wastewater treatment, but their efficiencies in practical printing and dyeing wastewater (PPDW) treatment are unknown. Herein, an PSBF was prepared, and its performance is discussed in comparison to polyaluminium chloride (PAC) and polyacrylamide (PAM) in PPDW treatment. The PSBF was used in three ways: as an independent flocculant, as a PAC aid, or used to treat the effluent of the PAC system. The results indicated that adding PSBF alone produced similar color and chemical oxygen demand (COD_Cr) removals as the PAC system alone, but PSBF performed better than PAC when the pH of PPDW was higher than 7.0. Adding PSBF as a PAC aid improved the color, COD_Cr and turbidity removals, but the elimination efficiencies were slightly lower than those of the PAC+ PAM system. However, when PSBF was used as a flocculant to treat the effluent of the PAC system (PAC→PSBF), the effluent qualities were enhanced. Compared with the PAC system, the color and COD_Cr removals of PAC→PSBF system increased by 16.21% and 13.26%, respectively. The excitation and emission matrix fluorescence results indicated that PSBF removed tryptophan-like pollutants more efficiently than PAC. Considering the pH requirements of the subsequent bioreactor treatment in practice, the PAC→PSBF system were also investigated at the PPDW pH level of 7.0. Its maximum removal efficiencies of color, COD_Cr and turbidity were 90.17%, 32.60% and 82.50%, respectively.     

3D类器官模型的研究进展及其在化学品毒理学评价中的应用展望

化学品毒理学评价主要采用2D细胞培养体系和动物实验模型,但2种模型均存在一定的局限性.2D细胞培养常用特定细胞系,与体内多细胞组织及其生理功能差异较大.动物实验耗时、昂贵,并受伦理学限制,且存在种属差异问题.3D类器官模型可模拟组织器官的复杂结构和功能,产生细胞间和细胞-基质相互作用,与体内生理反应更为相似,因此能更准确地反映毒性效应和机理.类器官模型在化学品毒理学评价领域具有良好的应用前景,将显著提升毒理学基础研究能力以及对化学品风险评价和管理的支撑作用,但相关研究尚处于起步阶段.本文从类器官的生理学特性、构建方法及组织类型等方面,重点讨论了类器官模型在化学品毒理学研究中的适用性,并提出了存在的挑战和对策.     

烧结机细颗粒物PM_(2.5)排放特性

利用基于荷电低压颗粒物撞击器(ELPI)的颗粒物排放稀释采样系统,对不同烧结机组的机头、机尾、配料和整粒后的烟粉尘进行了PM2.5的现场测试。结果表明了各测试点位排放的PM2.5粒径分布和质量浓度分布特点。烧结机机头脱硫后虽然降低PM2.5的质量浓度,却增大了其粒数浓度,因此应对脱硫工艺进行优化。PM2.5单体颗粒形态有:球形颗粒、超细颗粒、不规则颗粒和烟尘集合体。PM2.5中SO2-4、有机碳(OC)、无机碳(EC)和铁(Fe)的含量较高,分别为2.65%~10.76%,6.15%~12.6%,3.05%~10.05%和4.14%~26.78%。     

C60-DOM interactions and effects on C60 apparent solubility: a molecular mechanics and density functional theory study

Dissolved organic matter (DOM) plays a critical role in the transport of carbon nano-particles (e.g. C(60)) in the aquatic environment. However, the mechanism for C(60)-DOM interactions and its environmental implications needs further investigations. In this study, the interaction of C(60) with relevant reference compounds of DOM (DOM(R)) is computationally simulated by molecular mechanics and density functional theory (DFT). All the C(60)-DOM(R) complexes are firstly optimized by classical annealing, and then DFT using the Dmol(3) code. The adsorption energies of C(60) on DOM(R) were computed. The computed electrostatic potential indicates that DOM(R) are electron acceptors in the C(60)-DOM(R) complexes, and the thermodynamic calculations indicate that electrostatic interaction is the dominant driving force for the C(60)-gallic acid complexation process in water. The presence of DOM(R) increases the apparent water solubility of C(60). It is also observed that the C(60) apparent water solubility decrease with the increase of the energy gaps of frontier molecular orbitals (E(LUMO)-E(HOMO)) for each C(60)-DOM(R) complex. These findings indicate that computational simulation is an important tool for predicting the behavior and fate of carbon nano-particles in the aquatic environment.     

Polybrominated diphenyl ethers in soils of the modern Yellow River Delta, China: occurrence, distribution and inventory

The Yellow River is the second largest river in China. In this study, the levels of polybrominated diphenyl ethers (PBDEs) in the modern Yellow River Delta (mYRD) were firstly reported. Twenty PBDE congeners in soil/sediment samples from mYRD were measured. The total PBDE concentrations ranged from non-detectable to 18 257 ng kg⁻¹ with a mean value of 836 ng kg⁻¹. BDE-209 was the dominant congener, accounting for ∼86.1-99.5% of the total PBDEs. The congener profiles of PBDEs with higher abundances of BDE-153 and BDE-183 were similar to those in sediment of the Bohai Sea, indicating that they shared similar sources. The concentrations and congener patterns varied among different regions. Higher levels of PBDEs were found in the middle area (MA), and more complicated congener compositions were also observed in the MA, whereas lower levels of PBDEs were found in the modern course (MC) and the old course (OC). Much more PBDEs were detected in the top layer (TL) soil where more congeners were also held compared to lower soil layers, implying that more PBDEs were emitted into this area in recent years/decades. Organic matter controlled the PBDE distribution in the soil. Soil in this area might be a source of BDE209 for the Bohai Sea.     

防治油气集输过程中烃类污染的主要途径

烃类是油气田主要的大气污染物,主要来源于油气集输过程中的烃类损耗。降低烃类损耗,回收挥发气体,是减少大气污染的重要途径。孤东油田应用大罐抽气、原油稳定、轻烃回收等工艺对烃类进行回收治理,文章介绍了使用的工艺系统,分析了治理技术的经济效益,得出结论：采用大罐抽气、原油稳定和轻烃回收技术防治油气田烃类污染是可行的,技术成熟,工艺较简单,投资少,见效快,效益明显。在油气田全面推广应用,可以大大降低油气田的烃类污染负荷     

采用实验和密度泛函理论计算揭示吸光性环境介质对多环芳烃光降解的影响机制

多环芳烃(PAHs)在环境中的光降解动力学受环境介质吸光组分的影响.为揭示介质吸光组分对PAHs光降解影响的内在机制,以吸光很弱的甲醇和吸光较强的丙酮和二甲基亚砜(DMSO)为模拟环境介质,考察不同吸光性溶剂介质对3种PAHs(菲、芘和苯并[a]芘)光解的影响;并采用密度泛函理论(DFT)计算,分析了溶剂分子光敏化能量/电子转移反应对PAHs光解的影响机制.结果表明,激发态的丙酮分子抑制了菲和芘的光解,而加快了苯并[a]芘的光解;激发态的DMSO分子抑制了菲的光解,促进了芘和苯并[a]芘的光解.过滤掉DMSO所吸收的部分光谱频段后,PAHs在DMSO中的光解速率与甲醇中的接近.DFT计算表明,激发态的丙酮或DMSO主要作为电子受体与PAHs发生光敏化电子转移反应,是影响PAHs光解的内在原因.     

南昌市PM2.5中游离氨基酸的浓度、来源与分布特征

于2021年3—4月在南昌市森林地区和城市地区采集大气PM_2.5样品,测定其游离氨基酸(Free Amino Acids,FAAs)浓度.结果表明,南昌市森林地区大气气溶胶中总FAAs浓度为0.093～0.885 nmol·m^-3,平均浓度为(0.451±0.197)nmol·m^-3;城市地区大气气溶胶中总FAAs浓度为0.393～1.316 nmol·m^-3,平均浓度为(0.586±0.227)nmol·m^-3;森林地区FAAs浓度明显低于城市地区.对氨基酸组成占比分析发现,森林与城市地区氨基酸组成相似,最丰富的氨基酸均为Pro,Gly次之,Ala、Val、Leu、Ile为主要氨基酸.城市地区疏水性氨基酸(46.25%)高于森林地区(41.57%),这说明疏水性FAAs可能更适合在城市空气中聚集.通过相关性分析发现,温度对城市地区多个FAA浓度均有显著影响(p<0.05).随着温度的升高,FAAs浓度也升高.O₃对城市FAAs有显著影响(r=0.6...