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Ultraviolet humic-like component contributes to riverine dissolved organic matter biodegradation

Journal of Environmental Sciences 2023年第2期124卷 165-175页

作者： Maofei Ni siyue li College of Eco-Environmental Engineering Guizhou Minzu UniversityGuiyang 550025China Research Center for Environmental Ecology and Engineering School of Environmental Ecology and Biological EngineeringWuhan Institute of TechnologyWuhan 430205China The karst environmental geological hazard prevention laboratory of Guizhou Minzu University Guiyang 550025China Key Laboratory of Reservoir Aquatic Environment Research Center for EcohydrologyChongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China

Biological degradation of dissolved organic matter(DOM)regulates its structure and fate in river ecosystems.Previous views suggested that labile components were dominantly consumed by microbial metabolism.Here we provide new observations that a part of recalcitrant compounds largely contribute to riverine DOM biodegradation.The excitationemission matrix fluorescent spectroscopy combined with peak picking and parallel factor analysis are used to explore component variability during DOM incubation.Humic-like and tryptophan-like DOM are the primary components of riverine DOM,with proportion contributions of 39%–82% and 16%–61% for % of the maximumfluorescence intensity,respectively.After 56 days of aerobic incubation in the dark,large amounts of tyrosine-like DOM generation are observed.Elevated temperature enhances the decomposition of ultraviolet humiclike substance and further stimulates labile DOM bio-mineralization into carbon dioxide.Meanwhile,averaged proportions of amino acid compositions(peak B and T)markedly increase(plike compositions(peak A,M and C)decrease after DOM incubation,suggesting incomplete degradation of refractory DOM from high-molecular to low-molecular weight compounds.The findings support the new notion of the continuous DOM biodegradation in a mode as“steps by steps”,contributing to a new understanding of carbon cycling for the UN Sustainable Development Goal.

关键词： Dissolved organic matter(DOM) Sequential biodegradation Recalcitrant compounds Component and fate Fluorescence analysis

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Anthropogenic land use substantially increases riverine CO_(2) emissions

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Journal of Environmental Sciences 2022年第8期34卷 158-170页

作者： Shijie Gu siyue li Isaac R.Santos School of River and Ocean Engineering Chongqing Jiaotong UniversityChongqing 400074China Key Laboratory of Reservoir Aquatic Environment Chongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China Chongqing School University of Chinese Academy of SciencesChongqing 400714China Research Center for Environmental Ecology and Engineering Institute of Changjiang Water Environment and Ecological SecuritySchool of Environmental Ecology and Biological EngineeringKey Laboratory for Green Chemical Process of Ministry of EducationKey Laboratory of Novel Reactor and Green Chemical Technology of Hubei ProvinceEngineering Research Center of Phosphorus Resources Development and Utilization of Ministry of EducationWuhan Institute of TechnologyWuhan 430205China Department of Marine Sciences University of GothenburgGothenburg 41296Sweden National Marine Science Centre Southern Cross UniversityCoffs HarbourNSW 2450Australia

Carbon dioxide(CO_(2)) emissions from inland waters to the atmosphere are a pivotal component of the global carbon budget. Anthropogenic land use can influence riverine CO_(2) emissions, but empirical data exploring cause-effect relationships remain limited. Here, we investigated CO_(2) partial pressures(pCO_(2)) and degassing in a monsoonal river(Yue River)within the Han River draining to the Yangtze in China. Almost 90% of river samples were supersaturated in CO_(2) with a mean ± standard deviation of 1474 ± 1614 μatm, leading to emissions of 557-971 mmol/m^(2)/day from river water to the atmosphere. Annual CO_(2) emissions were 1.6-2.8 times greater than the longitudinal exports of riverine dissolved inorganic and organic carbon. pCO_(2) was positively correlated to anthropogenic land use(urban and farmland), and negatively correlated to forest cover. p CO_(2) also had significant and positive relationships with total dissolved nitrogen and total dissolved phosphorus. Stepwise multiple regression models were developed to predict p CO_(2) . Farmland and urban land released nutrients and organic matter to the river system, driving riverine p CO_(2) enrichment due to enhanced respiration in these heterotrophic rivers. Overall, we show the crucial role of land use driving riverine pCO_(2) , which should be considered in future large-scale estimates of CO_(2) emissions from streams. Land use change can thus modify the carbon balance of urban-river systems by enhancing river emissions, and reforestation helps carbon neutral in rivers.

关键词： River carbon Inland waters Greenhouse gases Climate change Water quality Headwater streams

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Influence of anisotropic stress path and stress history on stiffness of calcareous sands from Western Australia and the Philippines

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第1期14卷 197-209页

作者： Huan He siyue li Kostas Senetakis Matthew Richard Coop Songyu liu Institute of Geotechnical Engineering Southeast UniversityNanjing210096China Department of Architecture and Civil Engineering City University of Hong KongKowloonHong KongChina Department of Architecture and Civil Engineering Yeung Kin Man Academic BuildingBlue Zone 6/FCity University of Hong KongKowloonHong KongChina Department of Civil Environmental and Geomatic EngineeringUniversity College LondonLondonUK

Investigation of dynamic properties of carbonate/calcareous soils is important in earthquake and offshore engineering as these soils are commonly encountered in large-scale projects related with energy geomechanics and land reclamation.In this study,the stiffness and stiffness anisotropy of two types of calcareous sands(CS)from the Western Australia and the Philippines were examined using bender elements configured in different directions in stress path setups.Stiffness measurements were taken on specimens subjected to constant p’compression/extension and biaxial stress paths and additional tests were performed on three types of silica sands with different geological origins and particle shapes,which were used as benchmark materials in the study.Compared with the three brands of silica sands,the stiffness of the CS was found to be more significantly influenced by anisotropic loading;an important observation of the experimental results was that stress anisotropy had different weighted influences on the stiffness in different directions,thus influencing stiffness anisotropy.Comparisons were made between the specimens subjected to complex loading paths,and respected model parameters as suggested from published expressions in the literature.These comparisons further highlighted that calcareous soils have different responses in terms of stiffness,stiffness anisotropy and loading history,compared with that of silica-based sands.

关键词： Calcareous soils Dynamic properties Shear stiffness Stress anisotropy Stress history

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A New Perspective for Parkinson's Disease:Circadian Rhythm

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Neuroscience Bulletin 2017年第1期33卷 62-72页

作者： siyue li Yali Wang Fen Wang li-Fang Hu Chun-Feng liu Department of Neurology and Suzhou Clinical Research Center of Neurological Disease The Second Affiliated Hospital of Soochow University Institutes of Neuroscience Soochow University

Circadian rhythm is manifested by the behavioral and physiological changes from day to night, which is controlled by the pacemaker and its regulator. The former is located at the suprachiasmatic nuclei （SCN） in the anterior hypothalamus, while the latter is composed of clock genes present in all tissues. Circadian desynchronization influences normal patterns of day-night rhythms such as sleep and alertness cycles, rest and activity cycles. Parkinson＇s disease （PD） exhibits diurnal fluctuations. Circadian dysfunction has been observed in PD patients and animal models, which may result in negative conse- quences to the homeostasis and even exacerbate the disease progression. Therefore, circadian therapies, including light stimulation, physical activity, dietary and social schedules, may be helpful for PD patients. However, the cellular and molecular mechanisms that underlie the circadian dysfunction in PD remain elusive. Further research on circadian patterns is needed. This article summarizes the existing research on the circadian rhythms in PD, focusing on the clinical symptom variations, molecular changes, as well as the available treatment options.

关键词： Parkinson＇s disease Circadian rhythm Sleep Dopamine

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基于GF-2影像的武汉市九峰山国家森林公园地上碳储量估算

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地质通报 2024年第4期43卷 611-619页

作者：韩云亭李思悦罗协武汉工程大学环境生态与生物工程学院湖北武汉430205

探究国产高分辨率数据在森林碳储量估算研究中的潜力,为构建森林碳储量估算模型提供新思路。选取武汉市九峰山国家森林公园为研究对象,以GF-2遥感影像为数据源,结合地面实测信息,对研究区森林地上碳储量进行估算,共提取6个植被指数、4... 详细信息

探究国产高分辨率数据在森林碳储量估算研究中的潜力,为构建森林碳储量估算模型提供新思路。选取武汉市九峰山国家森林公园为研究对象,以GF-2遥感影像为数据源,结合地面实测信息,对研究区森林地上碳储量进行估算,共提取6个植被指数、4个波段值、8种纹理特征,筛选出9个与实测碳储量相关的遥感变量,运用线性与非线性方程对单个高相关变量和多个相关变量进行建模,选出最优模型,为进一步提高预测精度,将模型代入4种纹理窗口(3×3、5×5、7×7、9×9)。结果表明:通过遥感图像提取的植被指数之间,具有较强的共线性,单变量建立的模型精度低于多变量模型;利用均方根误差RMSE与决定系数R^(2)对4个窗口下模型的预测精度进行评价,模型在5×5窗口下预测效果最好(R^(2)=0.73,RMSE=0.5),3×3窗口下预测效果最差(R^(2)=0.64,RMSE=0.8),将所有估测模型进行比较,在纹理窗口下模型精度提高了0.11。利用5×5窗口下构建的多变量模型对研究区碳储量进行估算,九峰山国家森林公园碳储总量为1.06×10^(4) t,总体平均碳密度为84.59 t/hm^(2),具有一定的固碳作用。选用国产高分辨率影像GF-2数据对武汉市九峰山森林公园进行反演研究,能很好地运用在森林植被碳储量定量与生长状况领域。研究结果对“双碳”目标下森林生态系统碳汇监测与管理具有重要科学意义。

关键词： GF-2 地上碳储量遥感反演森林碳汇湖北

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Effects of length and application rate of rice straw mulch on surface runoff and soil loss under laboratory simulated rainfall

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International Journal of Sediment Research 2021年第4期36卷 468-478页

作者： Misagh Parhizkar Mahmood Shabanpour Manuel Esteban Lucas-Borja Demetrio Antonio Zema siyue li Nobuaki Tanaka Artemio Cerdà Soil Science Department Faculty of Agricultural Sciences University of Guilan Department AGRARIA Mediterranean University of Reggio Calabria Research Center for Ecohydrology Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences Escuela Técnica Superior Ingenieros Agrónomos y Montes Universidad de Castilla-La Mancha.Campus Universitario Ecohydrology Research Institute The University of Tokyo Forests Graduate School of Agricultural and Life Sciences The University of Tokyo Soil Erosion and Degradation Research Group Department of Geography University of Valencia

Forest land affected by deforestation yields high soil and water losses.Suitable management practices need to be found that can reduce these losses and achieve ecological and hydrological sustainability of the deforested areas.Mulch has been found to be effective in reducing soil losses;straw mulch is easy to apply,contributes soil organic matter,and is efficient since the day of application.However,the complex effects of rice straw mulch with different application rates and lengths on surface runoff and soil loss have not been clarified in depth.The current paper evaluates the efficiency of rice straw mulch in reducing the hydrological response of a silty clay loam soil under high intensity and low frequency rainfall events(tap water with total depth of 49 mm and intensity of 98 mm/h) simulated in the laboratory.Surface runoff and soil loss at three lengths of the straw(10,30,and 200 mm) and three application rates(1,2,and 3 Mg/ha) were measured in 50 cm(width) × 100 cm(length) × 10 cm(depth) plots with disturbed soil samples(aggregate soil size linear functions of mulch application rate and length,and can be used for a suitable hydrological management of soil.It is concluded that,thanks to rice straw mulch used as an organic soil conditioner,soil erosion and surface runoff are significantly(at p ling of the hydrological effects of mulching from the p

关键词： Straw mulch Soil erosion Mulch application rate Mulch length Rainfall simulator

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沉积物异化铁还原耦合植酸去磷酸化

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环境科学与技术 2024年第2期47卷 53-59页

作者：乐静全江伟欣潘伟杰钱毅光李思悦武汉工程大学环境生态与生物工程学院湖北武汉430205 深圳市环境水务集团有限公司广东深圳518035

研究沉积物中微生物驱动的异化铁还原与有机磷降解转化的耦合作用,对深入阐明水体富营养化发生机制、控制环境磷污染和应对潜在的全球性磷危机具有重要的现实意义。该研究以沉积物异化铁还原与有机磷降解转化耦合的环境效应为切入点,探... 详细信息

研究沉积物中微生物驱动的异化铁还原与有机磷降解转化的耦合作用,对深入阐明水体富营养化发生机制、控制环境磷污染和应对潜在的全球性磷危机具有重要的现实意义。该研究以沉积物异化铁还原与有机磷降解转化耦合的环境效应为切入点,探究了异化铁还原促进植酸有机磷去磷酸化的可行性。首先通过对武汉东湖自然沉积物中有机磷与亚铁含量的监测,以及两者之间的相关性分析,发现在以有机质降解为驱动力的早期成岩过程中,三价铁逐渐被还原为亚铁,同时伴随着有机磷含量的降低,揭示沉积物中铁的异化还原可能促进有机磷的降解转化;接着利用富集的沉积物内源微生物群落在实验室构建“异化铁还原微生物群落+水铁矿+植酸”微宇宙模拟系统,开展了铁还原微生物群落驱动异化铁还原对植酸有机磷降解转化作用的研究,进一步证实铁的异化还原能促进植酸有机磷的去磷酸化并生成PO_(4)^(3-),很可能是诱导水体富营养化的潜在新机制。

关键词：异化铁还原植酸去磷酸化沉积物内源有机磷

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ICP-MS法测定帕立骨化醇中11种元素杂质的含量

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中国医药工业杂志 2024年第4期55卷 571-577页

作者：李一芒姚莉蓓李思阅于新颖韩飞沈阳药科大学药学院辽宁沈阳110016

建立了电感耦合等离子体质谱(ICP-MS)法测定帕立骨化醇(1)中铅(Pb)、镉(Cd)、汞(Hg)、砷(As)、钴(Co)、钒(V)、镍(Ni)、锂(li)、锑(Sb)、铜(Cu)、铬(Cr)11种元素杂质的含量。采用微波消解法对样品进行前处理,以铋(Bi)、锗(Ge)和钪(Sc)... 详细信息

建立了电感耦合等离子体质谱(ICP-MS)法测定帕立骨化醇(1)中铅(Pb)、镉(Cd)、汞(Hg)、砷(As)、钴(Co)、钒(V)、镍(Ni)、锂(li)、锑(Sb)、铜(Cu)、铬(Cr)11种元素杂质的含量。采用微波消解法对样品进行前处理,以铋(Bi)、锗(Ge)和钪(Sc)为内标,采用动能甄别(KED)碰撞模式,玻璃同心雾化器进样,射频正向功率为1300 W,雾化气流速为0.8 L/min,等离子体气流速为15.0 L/min,辅助气流速为1.2 L/min。结果显示,11种待测元素在25%~200%浓度范围内线性关系良好;定量限在0.007~2.023 ng/mL;平均加样回收率(n=9)在86.0%~104.9%;重复性试验RSD(n=6)均≤2.3%。建立的方法准确且灵敏度高,可用于1中11种元素杂质的痕量控制。

关键词：帕立骨化醇电感耦合等离子体质谱微波消解元素杂质

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基于水热耦合的寒区隧道仰坡稳定性研究

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河南科技 2024年第10期51卷 50-54页

作者：李思悦刘志强兰州交通大学甘肃兰州730070

【目的】研究我国西北部寒冷地区的隧道仰坡稳定性及其季节温度效应的变化规律。【方法】建立寒区隧道仰坡的水热全耦合数学模型,以冻融环境变化为模拟分析基础,对其水热环境和稳定性进行数值模拟计算。【结果】结果表明,寒区隧道仰坡... 详细信息

【目的】研究我国西北部寒冷地区的隧道仰坡稳定性及其季节温度效应的变化规律。【方法】建立寒区隧道仰坡的水热全耦合数学模型,以冻融环境变化为模拟分析基础,对其水热环境和稳定性进行数值模拟计算。【结果】结果表明,寒区隧道仰坡稳定性与土体冻融状态相关;临空面土体受环境温度影响较为明显,而内侧土温变化不显著。【结论】当温度降低,土体冻结层厚度增加时,仰坡稳定性表现较好;气温回暖季节冻融层融化,仰坡破坏滑移面几乎与坡面平行并向上延伸,极易发生滑塌灾害。

关键词：寒区隧道仰坡冻-融状态水-热耦合数值模拟边坡稳定性

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Synthesis of spherical nano-ZSM-5 zeolite with intergranular mesoporous for alkylation of ethylbenzene with ethanol to produce m-diethylbenzene

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Chinese Journal of Chemical Engineering 2024年第3期67卷 298-309页

作者： siyue Wang Jinhong li Qingxin Xu Shengjie Song Yu'ni Jiang lidong Chen Xin Shi Weiguo Cheng Faculty of Chemistry and Chemical Engineering Liaoning Normal UniversityDalian 110629China Beijing Key Laboratory of Ionic liquids Clean Process Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China

Catalytic synthesis of m-diethylbenzene(m-DEB)through alkylation of ethylbenzene(EB)may be a promising alternative route in comparison with traditional rectification of mixed DEB,for which the top priority is to develop efficient and stable heterogeneous catalysts.Here,the spherical nano-ZSM-5 zeolite with abundant intergranular mesoporous is synthesized by the seed-mediated growth method for alkylation of EB with ethanol to produce m-DEB.The results show that the spherical nano-ZSM-5 zeolite exhibits better stability and higher alkylation activity at a lower temperature than those of commercial micropore ZSM-5.And then,the spherical nano-ZSM-5 is further modified by La_(2)O_(3) through acid treatment followed by immersion method.The acid treatment causes nano-ZSM-5 to exhibit the increased pore size but decreased the acid sites,and subsequent La_(2)O_(3) loading reintroduces the weak acid sites.As a result,the HNO_(3)-La_(2)O_(3)-modified catalyst exhibits a slight increase in EB conversion and DEB yield in comparison with unmodified one,and meanwhile,it still maintains high m-DEB selectivity.The catalyst after acid treatment achieves higher catalytic stability besides maintaining the high alkylation activity of EB with ethanol.The present study on the spherical nano-HZSM-5 zeolite and its modification catalyst with excellent alkylation ability provides new insights into the production of mDEB.

关键词： Zeolite Modification Alkylation reaction m-diethylbenzene Catalyst Fixed-bed

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