海拉尔盆地地下水铀的分布特征及富集规律

通过采集海拉尔盆地地表水样品12件,地下水样品67件,运用Durov图、等值线图和铀形态计算理论,结合数理统计方法,分析研究区域地下水铀的分布特征和赋存形态,结果表明:海拉尔盆地赫尔洪德凹陷地区主要为HCO₃-Ca·Na型,蹉岗隆起、乌尔逊凹陷和贝尔凹陷地区主要为Cl-Na型和HCO₃-Na型,巴彦山隆起地区主要为HCO₃-Na型,红旗牧场和新宝力格凹陷主要为Cl-Na型.研究区域铀的分布范围为17~425μg/L,平均值为80μg/L,标准偏差为70μg/L,引发了区域地源性地下水铀污染问题.地下水中以UO₂(CO₃)₃^4-和UO₂(CO₃)₂^2-的主要形式存在,与Eh表现的氧化还原环境具有一致性,其中呼伦贝尔湖东南部属于地下水铀成矿有利区域.潜在铀成矿范围属于重碳酸铀酰占优势的HCO₃型含铀地下水,铀酰碳酸盐复合物应占主导地位,铀的溶解与HCO₃^-的增加有关,地下水中的铀存在参与碳酸盐岩和硫酸盐岩的混合溶滤作用的可能性,UO₂(CO₃)₃^4-、UO₂(CO₃)₂^2-、U₄O₉和沥青铀矿等处于饱和状态,总Fe和(Ca²⁺+Mg²⁺)浓度较低,各种水化学指标对铀富集具有指示意义,因此可将其视为潜在铀源的参考依据.     

Acid Orange 7 degradation using methane as the sole carbon source and electron donor

• AO7 degradation was coupled with anaerobic methane oxidation. • Higher concentration of AO7 inhibited the degradation. • The maximum removal rate of AO7 reached 280 mg/(L·d) in HfMBR. • ANME-2d dominated the microbial community in both batch reactor and HfMBR. • ANME-2d alone or synergistic with the partner bacteria played a significant role. Azo dyes are widely applied in the textile industry but are not entirely consumed during the dyeing process and can thus be discharged to the environment in wastewater. However, azo dyes can be degraded using various electron donors, and in this paper, Acid Orange 7 (AO7) degradation performance is investigated using methane (CH₄) as the sole electron donor. Methane has multiple sources and is readily available and inexpensive. Experiments using ¹³C-labeled isotopes showed that AO7 degradation was coupled with anaerobic oxidation of methane (AOM) and, subsequently, affected by the initial concentrations of AO7. Higher concentrations of AO7 could inhibit the activity of microorganisms, which was confirmed by the long-term performance of AO7 degradation, with maximum removal rates of 8.94 mg/(L·d) in a batch reactor and 280 mg/(L·d) in a hollow fiber membrane bioreactor (HfMBR). High-throughput sequencing using 16S rRNA genes showed that Candidatus Methanoperedens, affiliated to ANME-2d, dominated the microbial community in the batch reactor and HfMBR. Additionally, the relative abundance of Proteobacteria bacteria (Phenylobacterium, Pseudomonas, and Geothermobacter) improved after AO7 degradation. This outcome suggested that ANME-2d alone, or acting synergistically with partner bacteria, played a key role in the process of AO7 degradation coupled with AOM.     

Photoelectrochemical technology for solar fuel generation,from single photoelectrodes to unassisted cells: a review

Environmental Chemistry Letters - Photoelectrochemical solar fuel generation requires a highly integrated technology for converting solar energy into chemical fuels. Dihydrogen (H2) and...     

Heterogeneous impacts of environmental regulation on foreign direct investment: do environmental regulation affect FDI decisions?

Environmental Science and Pollution Research - The industry selection effect occurring from the impact of environmental regulation on foreign direct investment (FDI) in China is heterogeneous....     

Influence of different inoculation densities of black soldier fly larvae (Hermetia illucens) on heavy metal immobilization in swine manure

The disposal of organic waste by the biocomposting of black soldier fly larvae (BSFL) has drawn broad attention. However, the discrepancies in heavy metal immobilization between BSFL biocomposting with different inoculation densities and aerobic composting need to be further researched. In this study, BSFL with inoculation densities of 0.08%, 0.24% and 0.40% was added to swine manure to investigate its influence on heavy metal bioaccumulation and bioavailability. The physicochemical properties, BSFL growth performance and amino acid contents were measured. The results showed that the germination index, total prepupal yield and bioavailable fraction removal rate (%) of Cr and Pb at an inoculation density of 0.40% of BSFL were the highest among all of the BSFL biocomposting groups. Although the bioaccumulation factor and heavy metal (Cd, Cr, Cu and Zn) concentrations of the BSFL body from swine manure with inoculation densities of 0.24% and 0.40% of BSFL were similar, the BSFL inoculation density of 0.40% had the best absorption effect on these heavy metals in terms of total prepupal yield. Therefore, this study provides a basis for exploring the optimal inoculation density of BSFL biocomposting to reduce the harmful effects of heavy metals in swine manure.

     

Fractional diffusion model for emission and adsorption prediction of TXIB from wallpaper

Environmental Science and Pollution Research - Mercury injection test shows that wallpaper is a porous building material with a complex fractal mass transfer channel. Therefore, fractional...     

高温蒸汽灭菌处理技术处置医疗废物工艺设计

高温蒸汽灭菌处理技术是近几年开发的新型医疗废物处置技术,并在全国部分地区得到了应用和推广。以西北某市医疗废物处置工程中高温蒸汽灭菌处理技术的应用为例,通过对其工程原理、系统组成、工艺流程等的分析论证共同探讨其工程原理和性能特点,为今后在工程实际中的运用提供参考。     

贵阳和万山地区部分蔬菜中的重金属含量及其健康风险

以贵州省贵阳市和万山地区为例,对购自当地自由市场的部分蔬菜中的重金属Cd、Hg、Pb、Mn、As的含量进行了测定,并以国际放射防护委员会(ICRP,International Commissionon Radiological Protection)给出的限定值为标准,对某些重金属含量超标的蔬菜进行了健康风险评价.结果表明:除个别蔬菜的As和Mn外,万山地区蔬菜中的重金属含量均明显高于贵阳地区;两地蔬菜中的As、Pb含量均低于国家限定值(GB4810-1994、GB14935-1994),而部分蔬菜中的Cd、Hg含量均明显超出国家限定值(GB15201-1994、GB2762-1994).风险评价结果表明贵阳和万山两地的蔬菜可能存在重金属Cd、Hg、Pb的中、轻度污染;存在Cd污染的蔬菜对人体的年致癌风险为3.40×10-7·a-1,非致癌物Hg和Pb对人体的总健康风险分别为3.63×10-7·a-1、1.69×10-6·a-1,均低于ICRP标准.     

节能型焦化污水生物脱氮新工艺的生产性试验研究

采用节能型生物脱氮新工艺对黑龙江某焦化厂的污水处理站进行生产性试验研究,结果表明:处理后出水达到GB8978-1996《污水综合排放标准》一级,并可回用于熄焦。该工艺适合推广应用于焦化污水、垃圾渗滤液、养殖、化肥等高含氮有机污水的处理。     

标准化作业确保人机两安全

通过研究作业过程 ,编制其标准化作业程序 ,使人、机、料、环 4个环节和谐统一 ,作业程序化、规范化。达到预防事故的目地 ,确保安全生产