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The great catastrophe: causes of the Permo-Triassic marine mass extinction

National Science Review 2024年第1期11卷 37-50页

作者： Paul B.Wignall David P.G.Bond school of earth & environment University of Leeds school of environmental Sciences University of Hull

The marine losses during the Permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). Planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling the Permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the Permian was likely Siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

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Continuous biohydrogen production from diluted molasses in an anaerobic contact reactor

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Frontiers of environmental Science & Engineering 2011年第1期5卷 140-148页

作者： Sheng CHANG Jianzheng LI Feng LIU State Key Laboratory of Urban water resource and environment School of Municipal and Environmental EngineeringHarbin Institute of TechnologyHarbin 150090China

An anaerobic contact reactor (ACR) systemcomprising a continuous flow stirred tank reactor (CSTR)with settler to decouple the hydraulic retention time(HRT) from solids retention time (SRT) was developedfor fermentative hydrogen production from dilutedmolasses by mixed microbial cultures. The ACR wasoperated at various volumetric loading rates (VLRs) of20-44 kgCOD·m^(-3)·d^(-1) with constant HRT of 6 h undermesophilic conditions of 35°C. The SRTwas maintained atabout 46-50 h in the system. At the initial VLR of20 kgCOD·m^(-3)·d^(-1), the hydrogen production rate droppedfrom 22.6 to 1.58 L·d^(-1) as the hydrogen was consumed bythe hydrogentrophic methanogen. After increasing theVLR to 28 kgCOD·m^(-3)·d^(-1) and discharging the sludge for6 consecutive times, the hydrogentrophic methanogenswere eliminated, and the hydrogen content reached 36.4%.As the VLR was increased to 44 kgCOD·m^(-3)·d^(-1), thehydrogen production rate and hydrogen yield increased to42.1 L·d^(-1) and 1.40 mol H2·molglucose-consumed^(-1),respectively. The results showed that a stable ethanoltypefermentation that favored hydrogen production inthe reactor was thus established with the sludgeloading rate (SLR) of 2.0-2.5 kgCOD·kgMLVSS-1·d^(-1).It was found that the ethanol increased more than otherliquid fermentation products, and the ethanol/acetic acid(mol/mol) ratio increased from 1.27 to 2.45 when the VLRincreased from 28 to 44 kgCOD·m^(-3)·d^(-1), whereas thehydrogen composition decreased from 40.4% to 36.4%.The results suggested that the anaerobic contact reactorwas a promising bioprocess for fermentative hydrogenproduction.

关键词： fermentative hydrogen production anaerobic contact reactor(ACR) sludge loading rate(SLR) butyric acid-type fermentation ethanol-type fermentation

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Effect of different gas releasing methods on anaerobic fermentative hydrogen production in batch cultures

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Frontiers of environmental Science & Engineering 2012年第6期6卷 901-906页

作者： Sheng CHANG Jianzheng LI Feng LIU Ze YU State Key Laboratory of Urban water resource and environment School of Municipal and Environmental EngineeringHarbin Institute of TechnologyHarbin 150090China

Decreasing hydrogen partial pressure can not only increase the activity of the hydrogen enzyme but also decrease the products inhibition, so it is an appropriate method to enhance the fermentative hydrogen production from anaerobic mixed culture. The effect ofbiogas release method on anaerobic fermentative hydrogen production in batch culture system was compared, i.e., Owen method with intermediately release, continuous releasing method, and continuous releasing ＋ CO2 absorbing. The experi- mental results showed that, at 35℃, initial pH 7.0 and glucose concentration of 10 g.L-1, the hydrogen produc- tion was only 28 mL when releasing gas by Owen method, while it increased two times when releasing the biogas continuously. The cumulative hydrogen production could reach 155 mL when carbon dioxide in the gas stream was continuously absorbed by 1 mol.L-1 NaOH. The results showed that acetate was dominated, accounting for 43% in the dissolved fermentation products in Owen method, whereas the butyrate predominated and reached 47%-53% of the total liquid end products when releasing gas continuously. It is concluded that the homoacetogenesis could be suppressed when absorbing CO2 in the gas phase in fermentative hydrogen production system.

关键词： batch fermentation hydrogen production,biogas releasing hydrogen pressure homoacetogenesis

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Decoratable hybrid-film-patch stabilized Pickering emulsions and their catalytic applications

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Nano Research 2015年第8期8卷 2603-2610页

作者： Shenghua Ma Yinan Wang Kunpeng Jiang Xiaojun Han State Key Laboratory of Urban water resource and environment School of Chemical Engineering and Technology Harbin Institute ofTechnology Harbin 150001 China

We demonstrated a method to fabricate functional hybrid film patches that were used to form Pickering emulsions （PEs）. The hybrid patches were made of carbon nanotubes, Fe3O4 nanoparticles, octadecyltrimethoxysilane, and poly（diallyldimethylammonium chloride）. The aqueous phase of the hybridpatch stabilized PEs can be easily separated by applying a magnetic field. The hybrid-film-patch stabilized PEs are extremely stable and lasted for eight months at room temperature. Furthermore, they are easily ruptured by adding ethanol, and regenerated by vortexing the patches in aqueous/oil mixtures, enabling the inner hydrophilic side of the patches to be easily modified with metal nanoparticles. As an example, palladium nanoparticles were embedded into the surface of the hybrid patches using an in situ reduction method. The Pd functionalized patch formed PEs showed an excellent catalytic performance for the hydrogenation of acetone with a yield of 99.5%. The same batch of Pd functionalized patches was recycled 13 times without loss of the catalytic activity. The hybrid-patch formed PEs have a great potential in the catalytic field.

关键词： Pickering emulsion hybrid film patches catalysis carbon nanotubes Fe3O4 nanoparticles

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Effects of temperature and surfactants on naphthalene and phenanthrene sorption by soil

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Journal of environmental Sciences 2009年第5期21卷 667-674页

作者： ZHANG Jinghuan ZENG Jianhui HE Mengchang State Key Laboratory of water environment Simulation School of Environment Beijing Normal University Beijing 100875 China Faculty of Natural resource & Information Technology China University of Petroleum Beijing 102200 China

Adsorption experiments were carried out to investigate the sorption behaviors of naphthalene and phenanthrene in six different soils and to determine the effects of temperature, linear alkylbenzene sulfonate （LAS） and cetylrimethyl ammonium bromide （CTAB） on sorption. The results show that for a given sorbent phenanthrene exhibited greater nonlinear and stronger sorption than naphthalene. There was a strong negative correlation for the Koc values with organic carbon content （foc）. The increase of temperature was not favorable to sorption. Sorption decreased along with the increasing aqueous LAS concentration from 0 to 1000 mg/L. At low CTAB concentration （〈 100 mg/L）, the adsorption increased as CTAB hemimicelles formed on the soil surface. At high concentration, CTAB decreased the adsorption by occupying active hydrophobic adsorption sites and solubilization of naphthalene and phenanthrene.

关键词： naphthalene phenanthrene sorption soil temperature linear alkylbenzene sulfonate cetylrimethyl ammonium bromide

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Publishing a sound paper of environmental science and ecological technology:Some experiences and tips for young researchers

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environmental Science and Ecotechnology 2023年第1期13卷 1-4页

作者： Shih-Hsin Ho Nan-Qi Ren school of environment Harbin Institute of TechnologyChina State Key Laboratory of Urban water resource and environment School of EnvironmentHarbin Institute of TechnologyChina

Two factors are of great significance for enhancing young researchers'international engagement:continuously improving their academic level and publishing advanced progress in scientific *** journals in the field of environmental science and ecological technology(ESET)are committed to improving research independency of young researchers,so as to promote excellent scientific research *** this editorial,we integrate major challenges that young researchers must cope with in preparing their submissions.

关键词： preparing young sound

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Characteristics of biomarker in source rocks of Linxi Formation in Taohaiyingzi region, Zhalute basin

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Chinese Journal Of Geochemistry 2015年第3期34卷 338-345页

作者： Li Liu You-jun Tang Xing-chao Jiang Key Laboratory of Exploration Technologies for Oil and Gas resources Ministry of Education School of Earth Environment and Water Resources Yangtze University

Based on gas chromatography and gas chromatography mass spectrometry techniques, the authors researched biomarker characteristics of the Linxi Formation source rocks in the area of Taohaiyingzi, and analyzed the information and petroleum geological significance that were indicated by source of organic matter, sedimentary environment, maturity and so on. Gas chromatography peak of saturated hydrocarbons from Linxi Formation source rocks showed ‘‘the former peak'' of the single peak distribution and the C23-dominant main peak. This indicates that the main source of organic matter was mixed organic matter; Pr/Ph ratios ranged from 0.3 to 0.6, indicating a strongly reducing sedimentary *** fossil assemblages in Linxi Formation source rocks were abundant in tricyclic terpane with long side chains, had high level of gammacerane, and showed dominant distribution of C27 steranes. Gammacerane ratios range from 0.15 to 0.29, with an average of 0.19, implying that Linxi Formation hydrocarbon source rocks were formed in the environment of micro-saltwater water to half-saltwater water. The hopanes/steranes ratios are mainly between 0.6 and 1.0, with an average of 0.84, implying that bacteria and algae had almost the samecontribution to organic matter. C27 steranes abundance is high and the ratio of C27steranes/C29 steranes is 1.13,showing that algae is the main source of hydrocarbon precursors.

关键词：生物标志物烃源岩特征比值范围盆地石油地质意义气相色谱沉积环境

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Design of an Index System for Deep Groundwater Management Efficiency Evaluation: A Case Study in Tianjin City, China

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Chinese Geographical Science 2016年第3期26卷 325-338页

作者： NAN Tian SHAO Jingli CAO Xiaoyuan ZHANG Qiulan CUI Yali school of water resources and environment China University of Geosciences (Beijing) Department of earth Ocean & Atmospheric Science Florida State University

An effective evaluation system can provide specific and practical suggestions to the deep groundwater management. But such kind of evaluation system has not been proposed in China. In this study, an evaluation index system is specifically developed to evaluate deep groundwater management efficiency. It is composed of three first-level indicators(law enforcement capability, management ability, and management effectiveness) and eleven second-level indicators. The second-level indicators include seven mandatory indicators and four optional indicators. Piecewise linear function is used to normalize the quantitative indicators, and expert scoring method and questionnaire survey method are used to normalize the qualitative indicators. Then a comprehensive indicator weighting evaluation method is used to evaluate the first-level indicators and the target topic. A case study is carried out to evaluate deep groundwater management efficiency in Tianjin City. According to the evaluation score in each period, the management efficiency of every district in Tianjin City gradually improved. The overall evaluation score in the early deep groundwater extraction period is 0.12. After a series of deep groundwater protection efforts, this score reached to 0.61 in 2007, and met the regulation criteria. The evaluation results also showed that the further groundwater management efforts in Tianjin City should be focused on building a dynamic database to collect comprehensive deep well-log data; and on a reasonable design and distribution of the groundwater monitoring network. It demonstrated that the index system is suitable to locate the deficiencies of current groundwater management systems and to guide further improvements. It can then be used to protect deep groundwater.

关键词： deep groundwater management evaluation index system law enforcement capability management ability management effectiveness

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Enhancement of sludge gravitational thickening with weak ultrasound

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Frontiers of environmental Science & Engineering 2012年第5期6卷 753-760页

作者： Panyue ZHANG Tian WAN Guangming ZHANG school of environment Science and Engineering Hunan UniversityChangsha 410082China State Key Laboratory of Urban water resource and environment Harbin Institute of TechnologyHarbin 150090China

Gravitational thickening is the prevailing method to reduce sludge volume but the process is slow and usually requires addition of polyelectrolyte（s）. This paper investigated the potential benefits of sonication on enhancing the sludge gravitational thickening with very low energy dose, so called ＂weak ultrasound＂. Results showed that weak sonication significantly changed the sludge settlability and the main mechanism was release of the loosely bounded extracellular polymeric substances. The changes in sludge behaviors by sonication were strongly influenced by power density and sonication duration. Lower sound frequency was slightly better than higher frequency. Weak sonication （〈 680 ***1 DS） improved the sludge gravitational thickening while high ultrasonic energy deteriorated the process. Considering both the sludge thickening efficiency and energy con- sumption the optimum conditions were 0.15 W. mL-l, 7 s, and 25 kHz. Under such conditions, the energy dose was only 155 ***-1 DS, much lower than literature reports, and the sludge settling time was shortened from 24 h to 12 h. Weak sonication could substitute expensive poly- electrolyte coagulant for sludge thickening. Combination of weak sonication and polyelectrolyte could further reduce the settling time to 6 h. The final water content of the thickened sludge was not changed after sonication or polyelectrolyte addition.

关键词： activated sludge sonication settlability dryweight extracellular polymeric substances polyelectrolyte

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Extraction of Metals from Boiler Slag by Sintering

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Journal of Wuhan University of Technology(Materials Science) 2009年第5期24卷 736-741页

作者：李进平侯浩波 school of resource and environment Science Wuhan University school of environment and Urban Construction Wuhan University of Science and Engineering

A new method of recycling aluminum and iron in boiler slag derived from plants that use coal as fuel was presented. The new method can integrate efficient extraction and reuse of the leached pellets together. An elemental analysis of aqueous solutions leached by sulfuric acid was conducted by the EDTA-Na2-ZnCl2 titration method, and the components and microstructures of the samples were examined by means of XRF, XRD and SEM. An aluminum extraction efficiency of 86.50% was achieved when the sintered pellets were leached using 4 mol·L-1 H2SO4 with solid/liquid ratio（m/V） of 1∶5 at 80 ℃ for 24 h. An iron extraction efficiency of 94.60% was achieved under the same condition for the maximum extraction efficiency of Al. The extraction efficiency of Al and Fe increased with temperature, leaching time and acidity. The concentration of alumina and iron hydroxide in the final product was determined to be 99.12% and 92.20% respectively. This product of alumina would be used directly for the production of metallic aluminum.

关键词： boiler slag Al extraction efficiency Fe extraction efficiency leaching alumina

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