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17721. 题目: A stepwise processing strategy for treating highly acidic wastewater and comprehensive utilization of the products derived from different treating steps
文章编号: N21042605
期刊: Chemosphere
作者: Yanjuan Zhang, Sisi Li, Songlin Fan, Yixiao Wu, Huayu Hu, Zhenfei Feng, Zuqiang Huang, Jing Liang, Yuben Qin
更新时间: 2021-04-26
摘要: A stepwise processing strategy, including initial neutralization, chemical mineralization, and complete neutralization treating steps, was developed to effectively treat and utilize the highly acidic wastewater derived from titanium dioxide production. Approximately 94.6% of SO42–, 100% of Fe, and most of other metals were recovered to produce white gypsum, schwertmannite, and Fe0/Fe3O4@biochar (Fe0/Fe3O4@BC) composite in the corresponding treating steps. The resulting effluent with neutral pH and a small amount of metal ions could be discharged to general sewage treatment plant for further processing. Schwertmannite was applied as a heterogeneous Fenton-like catalyst to stimulate H2O2 to produce active radicals for effective degradation and mineralization of methyl orange (MO) in solution. The MO removal of 100% and total organic carbon removal of 91.1% were achieved in schwertmannite/H2O2 reaction system, and schwertmannite exhibited good stability and reusability. Fe0/Fe3O4@BC composite was applied to remove Cr(VI), with the adsorption capacity of 67.74 mg g‒1. The removal of Cr(VI) using Fe0/Fe3O4@BC composite was a chemisorption process, including the adsorption of Cr(VI), reduction of Cr(VI) to Cr(III), and co-precipitation of Cr(III)/Fe(III) oxides/hydroxides. This stepwise treating strategy is a promising technology for effective treatment of highly acidic industrial wastewater and comprehensive utilization of the related products.

17722. 题目: Enhanced norfloxacin degradation by iron and nitrogen co-doped biochar: Revealing the radical and nonradical co-dominant mechanism of persulfate activation
文章编号: N21042604
期刊: Chemical Engineering Journal
作者: Mufan Xi, Kangping Cui, Minshu Cui, Yan Ding, Zhi Guo, Yihan Chen, Chenxuan Li, Xiaoyang Li
更新时间: 2021-04-26
摘要: The long-term abuse of antibiotics such as norfloxacin (NOR) poses a significant threat to aquatic environments. The development of efficient and economical treatments is still a pain point in the industry. Herein, we reported a directly robust carbonization-pyrolysis method to synthesize iron and nitrogen co-doped biochar material (Fe@N co-doped biochar) that was first applied to NOR removal through persulfate (PS) activation. The catalytic performance and operating factors were systematically investigated. It was found that 10 mg/L NOR achieved 95% degradation within 20 min under optimal reaction conditions. The removal rate of NOR could still achieve 80% and almost 50% of NOR was completely mineralized after five cycles. Through combined electron-paramagnetic-resonance analysis, quenching experiments, and X-ray-photoelectron-spectroscopy tests, •OH, •SO4-, and 1O2 were confirmed as reactive oxygen species in catalytic reaction. Iron activated PS to produce •OH and •SO4- through electron transfer and nitrogen-containing functional groups (graphitic N, C-OH/C=N) accepted electrons from PS to generate 1O2. The radical pathway involving hydroxyl radicals and the nonradical pathways involving singlet oxygen together accounted for the rapid degradation of NOR. The degradation pathways were comprehensively established, including defluorination, decarboxylation, piperazine ring breakage and nalidixic ring transformation. This study shed light on a new mechanism of radical and nonradical co-dominated PS activation and proposed a simple and inexpensive antibiotic wastewater treatment system.

17723. 题目: Enhancing anaerobic digestion of kitchen wastes via combining ethanol-type fermentation with magnetite: Potential for stimulating secretion of extracellular polymeric substances
文章编号: N21042603
期刊: Waste Management
作者: Qing Yu, Yafei Yang, Mingwei Wang, Yahui Zhu, Cheng Sun, Yaobin Zhang, Zhiqiang Zhao
更新时间: 2021-04-26
摘要: Magnetite, a common mineral that is abundant in the soils and sediments, has been widely documented to enhance the anaerobic digestion of organic wastes, whereas the mechanisms of magnetite promoting interspecies electron transfer are still unclear. In this study, under the conditions (ethanol-type fermentation) employed, magnetite stimulated the secretion of extracellular polymeric substances (EPS). Analysis of three-dimensional excitation emission matrix revealed that these EPS secreted in the presence of magnetite were primarily comprised of the redox-active organic functional groups. Electrochemical analysis showed that the EPS secreted with magnetite had the higher electron-accepting and electron-donating capacity than the EPS without magnetite. Syntrophomonas species capable of extracellularly transferring electron were enriched with supplementing magnetite. Together with the increased abundance of Methanospirillum and Methanobacterium species that could proceed direct interspecies electron transfer (DIET), the anaerobic digestion was likely improved due to the establishment of DIET with supplementing magnetite. As a result, anaerobic digestion of kitchen wastes was evidently enhanced. With decreasing the solid retention time to 30 d, the methane production rate only slightly declined to 18 ± 0.8 mL/g-VSS/d in the magnetite-supplemented digester, while almost no methane was detected in the digester without magnetite.

17724. 题目: Metagenomic insights into nitrogen and phosphorus cycling at the soil aggregate scale driven by organic material amendments
文章编号: N21042602
期刊: Science of The Total Environment
作者: Xingjie Wu, Jingjing Peng, Pengfei Liu, Qicheng Bei, Christopher Rensing, Yong Li, Huimin Yuan, Werner Liesack, Fusuo Zhang, Zhenling Cui
更新时间: 2021-04-26
摘要: The soil microbiome, existing as interconnected communities closely associated with soil aggregates, is the key driver in nutrient cycling. However, the underlying genomic information encoding the machinery of the soil microbiome involved in nutrient cycling at the soil aggregate scale is barely known. Here comparative metagenomics and genome binning were applied to investigate microbial functional profiles at the soil aggregate scale under different organic material amendments in a long-term field experiment. Soil samples were sieved into large macroaggregates (>2 mm), macroaggregates (0.25-2 mm) and microaggregates (<0.25 mm). Microbial taxonomic and functional alpha diversity were significantly correlated to soil NO3- and SOC. The highest abundance of nasB, nirK, and amoA genes, which are responsible for denitrification and ammonia oxidizers driving nitrification, was observed in microaggregates. Both manure and peat treatments significantly decreased the abundance of napA and nrfA that encode enzymes involved in dissimilatory nitrate reduction to ammonium (DNRA). As a biomarker for soil inorganic P solubilization, the relative abundance of gcd was significantly increased in macroaggregates and large macroaggregates. Three nearly complete genomes of Nitrososphaeraceae (AOA) and seven bacterial genomes were shown to harbor a series of genes involved in nitrification and P solubilization, respectively. Our study provides comprehensive insights into the microbial genetic potential for DNRA and P-solubilizing activity across different soil aggregate fractions and fertilization regimes.

17725. 题目: Diverse feedstock’s biochars as supplementary K fertilizer improves maize productivity, soil organic C and KUE under semiarid climate
文章编号: N21042601
期刊: Soil and Tillage Research
作者: Muhammad Ilyas, Muhammad Arif, Kashif Akhtar, Muhammad Riaz, Haiyan Wang
更新时间: 2021-04-26
摘要: The contemporary exhaustive agriculture has led to drastic reductions in soil potassium (K) status because of constant soil K mining by crops without sufficient recharge through external K inputs. Therefore, substituting and/or supplementing K through alternative sources has great prospects in developing countries like Pakistan, where imported K fertilizers are comparatively expensive. This two-year field study reports the effects of alternative sources of K as farmyard manure (FYM), sugarcane bagasse and woodchip, and their biochars (B) i.e. FYM-B, bagasse-B and woodchip-B on soil fertility, K availability, K use efficiency (KUE), soil organic carbon (SOC) and maize productivity in calcareous soil of the semiarid northern region of Pakistan. Alternative sources of K and their biochars were applied along mineral K fertilizer as muriate of potash (KCl) at 60 kg ha−1 rate in a randomized complete block design. Results showed that FYM–B significantly increased plant height, grains per cob and 1000-grain weight. The FYM–B increased grain yield by 6.5, 37.2, and 87.0% when compared with woodchip–B, chemical fertilizer and control treatments, respectively. Similarly, FYM–B and woodchip–B significantly increased SOC and soil available K contents as compared with the rest of the treatments. Grain K contents and KUE were generally higher in biochar than their feedstock treatments during both years. However, FYM–B resulted in significantly higher KUE compared to the other K sources and their biochars during both years. The biological and grain yields showed significant positive correlations with soil K and SOC contents. Our study concluded that FYM and FYM-B can be applied as alternative and/or supplementary K sources along woodchip-B and bagasse-B to improve maize productivity, KUE and SOC contents in nutrient poor soil. However, economic feasibility of such practices is required to be priorly investigated on long-term basis.

17726. 题目: Cotransport of uranyl carbonate loaded on amorphous colloidal silica and strip-shaped humic acid in saturated porous media: Behavior and mechanism
文章编号: N21042507
期刊: Environmental Pollution
作者: Wei Hou, Zhiwu Lei, Eming Hu, Hongqiang Wang, Qingliang Wang, Rui Zhang, Hui Li
更新时间: 2021-04-25
摘要: Uranyl carbonate (UC(VI)) is a stable form of uranyl (U(VI)) that widely coexists with amorphous colloidal silica (ACSi) and humic acid (HA) in carbonate-rich U-contaminated areas. In this context, the cotransport behavior and mechanism of UC(VI) with ACSi (100 mg·L−1) and HA colloids in saturated porous media were systematically investigated. It was found that the ACSi and strip-shaped HA have a strong adsorption capacity for UC(VI), and their adsorption distribution coefficient (Kd) is 4–5 orders of magnitude higher than that of quartz sand (QS). In the ternary system, UC(VI) was mainly existing in the colloid-associated form at low UC(VI) concentration (4.2 × 10–6 M). Compared with the individual transport of UC(VI), the presence of ACSi and strip-shaped HA in the binary system promotes the transport of low-concentration UC(VI) (4.2 × 10−6 M) but shows a hindering effect when UC(VI) = 2.1 × 10−5 M. When ionic strength (IS) increased from 0 to 100 mM, the individual transport of UC(VI) and ACSi was weakened owing to the masking effect and the compression of the electrical double layer, respectively; this weakening effect is more pronounced in the binary (UC(VI)–ACSi) system. Notably, the transport of UC(VI) and ACSi in the ternary system is independent of the changes in IS due to the surface charge homogeneity strengthening the electrostatic repulsion between HA and QS. The Derjaguin–Landau–Verwey–Overbeek theory and retention profiles reveal the co-deposition mechanism of ACSi and UC(VI) in the column under different hydrochemical conditions. The nonequilibrium two-site model and the mathematical colloidal model successfully described the breakthrough data of UC(VI) and ACSi, respectively. These results are helpful for evaluating the pollution caused by UC(VI) migration in an environment rich in HA and formulating corresponding effective control strategies.

17727. 题目: Influence of organic matter formed during oxidative processes in the catalytic reduction of nitrate
文章编号: N21042506
期刊: Journal of Environmental Chemical Engineering
作者: A. Sofia G.G. Santos, João Restivo, Carla A. Orge, M. Fernando R. Pereira, O. Salomé G.P. Soares
更新时间: 2021-04-25
摘要: The application of the catalytic reduction process to remove nitrate formed during the ozonation process of organic compounds in water was assessed to study the possibility of integrating both technologies to perform a simultaneous removal of organic and inorganic species present in water. Single ozonation of two model organic compounds (4-nitrobenzaldehyde and ampicillin) was performed in order to decompose the parent organic molecule. After the treatment with ozone, the obtained solution was forwarded to a catalytic reduction process, to convert nitrate (NO3-) formed during the previous process. Organic matter present in a solution after the treatment with ozone proved to negatively affect the efficiency of nitrate reduction due to possible adsorption on the catalyst active sites, inhibiting the conversion process. However, for solutions with a low concentration of organic matter (around 2mgL-1) it was possible to achieve NO3- conversion, although not complete during the reaction time used, and with high selectivity for ammonia formation. Several experiments were carried out to understand the effect of the organic matter on the catalyst performance, allowing to conclude that its adsorption on the catalyst surface would be the main cause of its deactivation. This issue was overcome by the application of bimetallic catalysts with high metal content (5% Pd-2.5% Cu) in different supports in the presence of organic matter, and an improvement in NO3- conversion was achieved, meaning that the presence of organic matter in solution does not completely deactivate the catalyst.

17728. 题目: Immobilization of lead and cadmium in agricultural soil by bioelectrochemical reduction of sulfate in underground water
文章编号: N21042505
期刊: Chemical Engineering Journal
作者: Fan Yang, Weiwei Zhai, Zhongjian Li, Ying Huang, Maria Manzoor, Bin Yang, Yang Hou, Lecheng Lei, Xianjin Tang
更新时间: 2021-04-25
摘要: In situ immobilization of lead (Pb) and cadmium (Cd) in agricultural soil with sulfide (S2-) is an effective remediation strategy. Considering irrigating farmland with underground water, Sulfate (SO42-) in underground water is an ideal S2- source for Pb and Cd immobilization. Herein, a bioelectrochemical remediation system was developed to immobilize Pb and Cd by coupling a bioelectrochemical sulfate-reducing reactor (SRR) with a soil immobilization reactor (SIR). In the SRR, SO42- in underground water was efficiently reduced to S2- by autotrophic sulfate-reducing bacteria (SRB) using hydrogen as an electron donor via electrochemical water splitting reactions. Inputting 20 mA electricity, 30 mg/L S2- was produced and 77.4% of bioavailable Pb was converted to organic matter bound (F4) and residual bound (F5). While, 49.0% of bioavailable Cd was converted to carbonates bound (F2) and iron and manganese bound (F3). The bioelectrochemical remediation system was also efficient for three other soils with different properties. In addition, the most dominant SRB in the SRR was identified with 16S rRNA sequencing. Furthermore, phytotoxicity of the treated soil was proved to be decreased than the original soil and SO42- in the treated soil could be continually reduced to S2- for immobilizing Pb and Cd. Our study provides a promising technology to remediate heavy metal polluted soil.

17729. 题目: Spatial variation and distribution of soil organic carbon in an urban ecosystem from high-density sampling
文章编号: N21042504
期刊: CATENA
作者: Pingping Zhang, Yunqiang Wang, Hui Sun, Lijun Qi, Hao Liu, Zhe Wang
更新时间: 2021-04-25
摘要: With acceleration of urban expansion, urban soils are increasingly becoming critical in the global carbon cycle. However, spatial variations and distributions of soil organic carbon (SOC) across urban centers are rarely investigated. Here, 1018 soil samples were collected from the upper 20 cm soil layer in Xi'an — a typical historical city under rapid urbanization in China. The aims were to: i) determine current levels and variations in SOC; ii) identify main driving factors of SOC density (SOCD); and iii) compare different interpolation methods in predicting spatial distributions of SOCD in Xi'an City study area. Results showed that the range of SOC concentration (SOCC) was 1.57–38.58 g kg−1 (mean of 13.59 g kg−1) and the range of SOCD was 0.47–9.48 kg m−2 (mean of 3.59 kg m−2). Analysis of coefficient of variation showed that there were moderate variations in SOCC (54.0%) and SOCD (49.4%) in the study area. Combined correlation analysis, principal component analysis and minimum dataset compilation showed that sand content, distance to civic center, land use type and vegetation type were closely correlated with spatial variations in SOCD. Geostatistical analysis showed that isotropic exponential model with a range of 1776 m was the best fit for SOCD semi-variogram. Spatial distribution of SOCD was further predicted using four approaches — ordinary kriging (OK), inverse distance weighting (IDW), multiple linear regression (MLG) and regression kriging (RK). The spatial prediction accuracy was ranked in order of RK > MLR > OK > IDW. However, there was relatively low interpolation accuracy for the four approaches. This was attributed to the high spatial variations in urban milieu, impacted by intense anthropogenic activities. The findings in this study added to current knowledge on global carbon cycle as influenced by urban soils, which is a critical guide to land management in urban areas.

17730. 题目: Eutrophication alters bacterial co‐occurrence networks and increases the importance of chromophoric dissolved organic matter composition
文章编号: N21042503
期刊: Limnology and Oceanography
作者: Lei Zhou, Yongqiang Zhou, Xiangming Tang, Yunlin Zhang, Guangwei Zhu, Anna J Székely, Erik Jeppesen
更新时间: 2021-04-25
摘要: Eutrophication affects bacterial communities by fueling them with nutrients and carbon sources. While the influence of physicochemical conditions on bacterial communities is well studied, little is known about how dissolved organic matter (DOM) quality affects bacterial interspecific interactions and community composition with increasing eutrophication. Here, we examined the relative importance of physicochemical conditions and chromophoric DOM (CDOM) composition for bacterial community variation across trophic gradients using 109 samples data collected in 33 lakes of the Yangtze‐Huaihe River basin. We found a notable increase of bacterial abundance, elevated modularity of co‐occurrence networks, and decreased habitat niche breadths from mesotrophic sites to hyper‐eutrophic sites, suggesting changes in co‐occurrence patterns with eutrophication. Variation partitioning revealed that the proportion purely explained by CDOM composition was higher at the moderate‐ and hyper‐eutrophic sites than at the mesotrophic sites. Moreover, the module structures of the networks correlated significantly with CDOM composition at the eutrophic sites but not at the mesotrophic sites. The significant negative correlation between community‐level habitat niche breadths and the intensities of the protein‐like components at the moderate‐ and hyper‐eutrophic sites indicates a strong association between biolabile protein‐like compounds and habitat specialists in nutrient and substrate enriched lake systems. Our results suggest that consideration of DOM composition can strengthen the identification of links between environmental factors and bacterial community composition and interspecific interactions, especially under resource‐rich conditions.

17731. 题目: Synthesis of PAC-LaFeO3-Cu nanocomposites via sol-gel method for the photo catalytic degradation of humic acids under visible light irradiation
文章编号: N21042502
期刊: Journal of Environmental Chemical Engineering
作者: Fahim Amini, Seperhr Padervand, Kamyar Yaghmaeian, Mirzaman Zamanzadeh, Somayeh Yousefi, Samaneh Abolli, Hamed Soleimani, Mahmood Alimohammadi
更新时间: 2021-04-25
摘要: Humic acids are natural organic substances that are produced as a result of biological and geochemical reactions in environment and are known as one of the main precursors of disinfectant by-products (DBPs). New types of PAC/LaFeO3/Cu nanocomposites are synthesized by sol gel method for photocatalytic degradation of humic acid under visible light irradiation. The physicochemical functions of PAC/LaFeO3/Cu nanocomposites were characterized using BET, TEM, UV-vis DRS, XRD, and PL spectroscopy. Results emphasize that, free hydroxyl radical (•OH) attack to HAs molecules, decompose and oxidize the molecules to CO2, H2O, and other small components. Central composite design (CCD) was applied to optimize HAs removal based on response surface methodology (RSM) with four experimental parameters such as pH (X1, 3-11), catalyst dosage (X2, 100-1300 mgL-1), contact time (X3, 15-55min), and HAs concentration (X4, 2-10 mgL-1). Removal efficiency of 95.5% for HAs has been obtained under optimal conditions with 36.20min (exposure time), 5.33 mgL-1 HAs concentration, 715.74 mgL-1 PAC/LaFeO3/Cu dosage, and 4.20pH. The HAs degradation efficiency was significantly affected by the initial dye concentration and the pH values. The significance of the polynomial model (Radjasted2=0.997,R2=0.985) was validated by analysis of variance (ANOVA). This work seeks to illustrate new knowledge for usage of nanocomposites photocatalyst as an inexpensive, environmentally friendly, economical, and effectual material for drinking water supplies treatment processes. However, the PAC/LaFeO3/Cu nanocomposites showed excellent removal performances for HAs.

17732. 题目: Fouling of TiO2 induced by natural organic matters during photocatalytic water treatment: mechanisms and regeneration strategy
文章编号: N21042501
期刊: Applied Catalysis B: Environmental
作者: Xuejia Yang, Hongwei Sun, Guiying Li, Taicheng An, Wonyong Choi
更新时间: 2021-04-25
摘要: Photocatalysis has been intensively investigated for the removal of pollutants but little attention was paid to the deactivation of photocatalysts during the long-term operation. Herein we used TiO2 as the model photocatalyst to investigate its durability in the presence of humic acid (HA), a ubiquitous constituent of real water. No sign of TiO2 deactivation was observed without HA, whereas significant deactivation occurred with HA. Interestingly, the adsorption of intact HA had only a minor contribution to the deactivation, and the major contributing factor was the adsorption of in-situ oxidized HA, which formed surface complexes with TiO2, blocked the active sites, and decreased the efficiency of photogenerated charge transfer. The regeneration of the deactivated TiO2 was also systematically investigated. The present study provides basic information that is required to understand and hinder the complex fouling phenomenon that can be serious in photocatalytic treatment of water containing natural organic matters.

17733. 题目: Algae Biofilm Reduces Microbe-Derived Dissolved Organic Nitrogen Discharges: Performance and Mechanisms
文章编号: N21042414
期刊: Environmental Science & Technology
作者: Yuan Lin, Liye Wang, Ke Xu, Hui Huang, Hongqiang Ren
更新时间: 2021-04-24
摘要: Microbe-derived dissolved organic nitrogen (mDON) can readily induce harmful phytoplankton blooms, and thus, restricting its discharges is necessary. Recently, algae biofilm (AB) has attracted increasing interest for its advantages in nutrient recovery. However, its features in mDON control remain unexplored. Herein, AB’s mDON formation and utilization performance, molecular characteristics, and metabolic traits have been investigated, with activated sludge (AS) as the benchmark for comparisons. Comparatively, AB reduced mDON formation by 83% when fed with DON-free wastewater. When fed with AS’s effluent, it consumed at least 72% of the exogenous mDON and notably reduced the amount of protein/amino sugar-like compounds. Irrespective of the influent, AB ultimately produced more various unsaturated hydrocarbon and lignin analogues. Redundancy and network analysis highlighted the algal–bacterial synergistic effects exemplified by cross-feeding in reducing mDON concentrations and shaping mDON pools. Moreover, metagenomics-based metabolic reconstruction revealed that cyanobacteria Limnothrix and Kamptonema spp. facilitated mDON uptake, ammonification, and recycling, which supplied the extensive nitrogen assimilatory demand for amino acids, vitamins, and cofactors biosynthesis, and therefore promoted mDON scavenging. Our findings demonstrate that regardless of the secondary or tertiary process, cyanobacteria-dominated AB is promising to minimize bioavailable mDON discharges, which has implications for future eutrophication control.

17734. 题目: The combined use of arbuscular mycorrhizal fungi, biochar and nitrogen fertilizer is most beneficial to cultivate Cichorium intybus L. in Cd-contaminated soil
文章编号: N21042413
期刊: Ecotoxicology and Environmental Safety
作者: Zhuojun Zhao, Lu Chen, Yan Xiao
更新时间: 2021-04-24
摘要: We assessed Cichorium intybus L. (chicory) growth, nutrients and Cd uptake in the presence of arbuscular mycorrhizal fungi (AMF), biochar (BC) and nitrogen (N) fertilizer applications in experimental pot studies. Mycorrhizal colonization was improved by BC addition but not N addition. However, in the presence of AMF, BC and N had positive effects on shoot biomass and plants grown in the presence of all 3 components yielded the highest levels of shoot biomass compared to pair-wise combinations or individual components singly added. AMF inoculation also increased root biomass and this effect was apparent in the combinations that included AMF without BC. Fungal inoculation also led to increased contents of phosphorus (P), magnesium (Mg) and copper (Cu) in both chicory shoots and roots and potassium (K) and manganese (Mn) in roots. Moreover, in the presence of BC, AMF inoculation evidently enhanced the shoot Ca content. In contrast, the presence of AMF inhibited plant Cd absorption and BC addition further inhibited root Cd concentration following the AMF inoculation. Applying N fertilizer alone increased Cd transfering from soil to plants. However, when combined with use of AMF and BC, Cd toxicity to plants was reduced. This study demonstrated that AMF inoculation combined with BC and N fertilizer could improve chicory growth, nutrient absorption and reduction of Cd uptake in Cd-contaminated soil.

17735. 题目: Hypophosphite Tailored Graphitized Hierarchical Porous Biochar toward Highly Efficient Solar Thermal Energy Harvesting and Stable Storage/Release
文章编号: N21042412
期刊: Chemical Engineering Journal
作者: Pan-Pan Zhao, Cong Deng, Ze-Yong Zhao, Peng Lu, Shuang He, Yu-Zhong Wang
更新时间: 2021-04-24
摘要: Utilization of renewable solar energy is a promising pathway to relieve the severe energy shortage in current fossil fuel society, for which phase change materials (PCMs) based on sustainable porous biomass carbon materials represent an attractive and enormously potential option. However, structural tailor of hierarchical pores independent of biomass natural structure is still difficult for these carbon materials, thus seriously limiting their efficiency in solar thermal energy harvesting and stable storage/release. In this work, hierarchical porous carbons (HPCs) derived from chestnuts were fabricated by using aluminum hypophosphite (AP) as a multifunctional (dehydrating, blowing, and crosslinking) activator. Different measurements confirmed that unique interpenetrating HPC network structures with continuous channels were tailored via the triple effects of AP. The resulting HPC displays high pore volume and high thermal conductivity. The HPC-stabilized composite PCM with 85 wt% octadecane (Octadecane85@HPC) possesses the high transition enthalpy of 216.2 J g-1 and shows high reliability in thermal cycle test. Compared with currently reported similar bio-based PCMs, the Octadecane85@HPC shows higher energy storage capacity. Interestingly, the solar thermal energy conversion efficiency of the Octadecane85@HPC reaches 96.1%, presenting excellent solar energy harvesting capacity. This work provides a promising strategy to tailor biomass HPC for highly efficient solar thermal energy harvesting and storage/release.

17736. 题目: Response of organic phosphorus in lake water to environmental factors: A simulative study
文章编号: N21042411
期刊: Science of The Total Environment
作者: Xiuling Bai, Yunkai Zhou, Wenna Ye, Hongyan Zhao, Jiehua Wang, Wenchao Li
更新时间: 2021-04-24
摘要: Transformation of organic phosphorus (P) is directly related to a range of environmental factors, therefore exploring their relationships is vital to understanding the biogeochemical cycling of P and its significance in eutrophication of lake waters. In this study, a series of experiments were conducted to simulate the organic P transformation in the water under the influence of dissolved oxygen (DO), temperature and phytoplankton growth. Results showed that the transformation rate of total organic P increased with temperature, ranging from 0.02 to 0.25 mg L−1 day−1 at 5 °C, and from 0.04 to 0.72 mg L−1 day−1at 30 °C. The transformation rate of total organic P was significantly higher under anaerobic conditions than that under aerobic conditions at 20 °C and 30 °C, indicating that DO is a more important factor for the transformation of total organic P at the high temperature. However, different compounds of organic P responded differently to environmental factors. The change of orthophosphate monoester (Mono-P) content was consistent with that of total organic P when the temperature and DO were the same, but the transformation rates of phosphonate and DNA in the water were less affected by changes of temperature and DO. Additionally, the transformation rate of Mono-P was increased by the growth of phytoplankton when it was used as a P source. Although the relationships between alkaline phosphatase (ALP) activity and organic P are complex, ALP may be the main factor affecting the transformation of organic P at lower temperatures.

17737. 题目: Protein-derived structures determines the redox capacity of humic acids formed during hyperthermophilic composting
文章编号: N21042410
期刊: Waste Management
作者: Xiaoming Liu, Yueqiang Wang, Weiwu Wang, Wenfeng Huang, Zhen Yu, Shungui Zhou
更新时间: 2021-04-24
摘要: Humic acid (HA) in compost has received widespread attention for its high redox activity, which can mediate the degradation of organic pollution and the passivation of heavy metals in the environment. Hyperthermophilic composting (HTC) can accelerate HA formation. However, few studies have examined whether and how the structures of different organics affect the formation of the HA and HA redox structure at the molecular level in HTC. Detailed molecular information and the redox capacity (electron transfer capacity, ETC) of HA in HTC and thermophilic composting (TC) were characterized using pyrolysis gas chromatography/mass spectrometry and the electrochemical method, respectively. HTC promoted the formation of redox structure, leading to the improvement of the ETC of HA. Aromatics and N-containing compounds were mainly derived from protein components, and the rate at which they were transferred into HA was accelerated in HTC, while the relative abundance of lipids decreased. Partial least squares regression and correlation analysis demonstrated that protein-derived compounds were the key factor determining the HA redox capacity. Finally, partial least squares path modeling suggested that the influence mechanism of protein-derived structures on HA redox capacity might differ in HTC and TC. HTC may promote the relative abundance of N-containing components into the C-skeleton and accelerate the accumulation of the aromatic products, thereby improve the HA redox capacity. These findings provided new insight into how the redox capacity of the HA in compost could be improved and how compost products could be prepared for use in environmental remediation.

17738. 题目: Correspondence between DOM molecules and microbial community in a subtropical coastal estuary on a spatiotemporal scale
文章编号: N21042409
期刊: Environment International
作者: Qi Chen, Feng Chen, Michael Gonsior, Yunyun Li, Yu Wang, Chen He, Ruanhong Cai, Jinxin Xu, Yimeng Wang, Dapeng Xu, Jia Sun, Ting Zhang, Quan Shi, Nianzhi Jiao, Qiang Zheng
更新时间: 2021-04-24
摘要: Dissolved organic matter (DOM) changes in quantity and quality over time and space, especially in highly dynamic coastal estuaries. Bacterioplankton usually display seasonal and spatial variations in abundance and composition in the coastal regions, and influence the DOM pool via assimilation, transformation and release of organic molecules. The change in DOM can also affect the composition of bacterial community. However, little is known on the correspondence between DOM molecules and bacterial composition, particularly through a systematic field survey. In this study, the spatiotemporal signatures of microbial communities and DOM composition in the subtropical coastal estuary of Xiamen are investigated over one and half years. The co-occurrence analysis between bacteria and DOM suggested microorganisms likely transformed the DOM from a relatively high (>400 Da) to a low (<400 Da) molecular weight, corresponding to an apparent increase in overall aromaticity. This might be the reason why microbial transformation renders “dark” organic matter visible in mass spectrometry due to more efficient ionization of microbial metabolites, as well as photodegradation processes. K- and r-strategists exhibited different correlations with two-size categories of DOM molecules owing to their different lifestyles and responses to environmental nutrient conditions. A comparison of the environmental variables and DOM composition with the microbial communities showed that the environmental/DOM variations played a more important role in shaping the microbial communities than vice versa. This study sheds light on the interactions between microbial populations and DOM molecules at the spatiotemporal scale, improving our understanding of microbial roles in marine biogeochemical cycles.

17739. 题目: Extracellular polymeric substances from Shewanella oneidensis MR-1 biofilms mediate the transformation of Ferrihydrite
文章编号: N21042408
期刊: Science of The Total Environment
作者: Wei Yan, Wen Guo, Liying Wang, Chuanyong Jing
更新时间: 2021-04-24
摘要: Extracellular polymeric substances (EPS) of dissimilatory iron-reducing bacteria (DIRB) such as Shewanella oneidensis MR-1 play a crucial role in the biotransformation of iron-containing minerals, but the mechanism has not been fully deciphered. Herein, abiotic and biotic transformation of ferrihydrite (Fh) were compared to clarify the contributions of MR-1, EPS-free MR-1 (MR-1-EPS), loosely bound EPS (LB-EPS), and tightly bound EPS (TB-EPS). The results of abiotic Fh transformation indicated that EPS did not block the Fh surfaces and thus has an insignificant effect on the adsorbed Fe(II)-Fh interaction. The complexation of the Fe(III) intermediate (Fe(III)active) with EPS, especially LB-EPS, however, inhibited the nucleation of secondary Fe minerals and changed the crystallization pathway. For biotic Fh transformation, on the other hand, EPS had dual effects that accelerated Fh bioreduction due to the enhanced extracellular electron transfer (EET) and constrained the following Fh mineralization by cutting of the chain reactions leading to mineral crystallization. Our finding also suggested that the effects of EPS on Fh biotransformation largely depend on the chemical properties of EPS, especially the polar functional groups such as carboxyl and phosphate, because of their important abilities for the cell attachment and Fe(II)/Fe(III) binding.

17740. 题目: Biochar in water and wastewater treatment - A sustainability assessment
文章编号: N21042407
期刊: Chemical Engineering Journal
作者: Mohammadreza Kamali, Lise Appels, Eilhann E. Kwon, Tejraj M. Aminabhavi, Raf Dewil
更新时间: 2021-04-24
摘要: Innovation of sustainable materials that are efficient, economic, environmentally friendly, and socially acceptable for real-scale environmental applications is currently a trend in the scientific community. Recently, biochar as one of the main pyrogenic products from thermo-chemical process of ligno-cellulosic biomass has been widely studied to deal with water pollutants and wastewaters. Thus, there is an urgent need for the assessment of developed technologies to promote commercialization of the most sustainable technologies in order to identify the existing technical gaps. This review aims to identify current trends in the literature in order to evaluate the technology against sustainability considerations, emphasizing on the recently published reviews as well as the highly cited papers. The existing gaps and recommendations for future studies are discussed.