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Soil nutrient loss due to tuber crop harvesting and its environmental impact in the North China Plain

Journal of Integrative Agriculture 2016年第7期15卷 1612-1624页

作者： yu han-qing LI Yong ZHOU Na Adrian Chappell LI Xiao-yu Jean Poesen Agricultural Clean Watershed Research Group Institute of Environment and Sustainable Development in AgricultureChinese Academy of Agricultural Sciences(CAA S)Beijing 100081P.R.China CSIRO Land&Water National Research Flagship Canberra ACT 2601Australia Division of Geography KU LeuvenHeverlee 3001Belgium

Soil loss due to crop harvesting （SLCH） is a soil erosion process that signiifcantly contributes to soil degradation in crop-lands. However, little is known about soil nutrient losses caused by SLCH and its environmental impacts. In the North China Plain area, we measured the losses of soil organic carbon （SOC） and nitrogen as wel as phosphorus due to SLCH and assessed their relationship with soil particle size composition, agronomic practices and soil moisture content. Our results show that the losses by harvesting potato of SOC, total nitrogen （TN）, available nitrogen （AN）, available phosphorus （AP） and total phosphorus （TP） were 1.7, 1.8, 1.8, 15.9 and 14.1 times compared by harvesting sweet potato, respectively. The variation of SOC, N and P loss by SLCH are mainly explained by the variation of plant density （PD）（17–50%）, net mass of an individual tuber （Mcrop/p）（16–74%）, soil clay content （34–70%） and water content （19–46%）. Taking into account the current sewage treatment system and the ratio of the nutrients adhering to the tubers during transportation from the ifeld （NTRP/SP）, the loss of TN and TP by harvesting of potato and sweet potato in the North China Plain area amounts to 3% N and 20% P loads in the water bodies of this region. The fate of the exported N and P in the sewage treatment system ultimately controls the contribution of N and P to the polution of lakes and rivers. Our results suggest that a large amount of SLCH-induced soil nutrient export during transportation from the ifeld is a potential polutant source for agricultural water for vast planting areas of tuber crops in China, and should not be overlooked.

关键词： soil nutrient losses potato sweet potato crop harvesting water polution

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Experimental system of coupled map lattices

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Frontiers of physics 2015年第3期10卷 101-104页

作者： yu-han Ma Lan-qing Huang Chu-Min Sun Xiao-Wen Li Department of Physics Beijing Normal University Beijing 100875 China

We design an optical feedback loop system consisting of a liquid-crystal spatial light modulator （SLM）, a lens, polarizers, a CCD camera, and a computer. The system images every SLM pixel onto one camera pixel. The light intensity on the camera pixel shows a nonlinear relationship with the phase shift applied by the SLM. Every pixel behaves as a nonlinear map, and we can control the interaction of pixels. Therefore, this feedback loop system can be regarded as a spatially extended system. This experimental coupled map has variable dimensions, which can be up to 512 by 512. The system can be used to study high-dimensional problems that computer simulations cannot handle.

关键词： coupled map lattices photoelectric feedback loop

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Integrated Use of Alternative Methods for Evaluating the Skin Sensitization Potencies of Five Frequently Used Preservatives in Cosmetics

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China Detergent & Cosmetics 2023年第2期8卷 38-47页

作者： Wang Rui Wang Huan han yu-qing Zhao Jinfeng Yan Shiyu Pan Yao Department of Cosmetics College of Chemistry and Materials EngineeringBeijing Technology and Business UniversityChina Beijing Key Laboratory of Plant Research and Development China Institute of Cosmetic Regulatory Science Beijing Technology and Business UniversityChina

In vitro skin sensitization testing methods based on the adverse outcome pathway(AOP)were used to evaluate the skin sensitization potencies of 5 commonly used *** to the“2 out of 3”principle of the integrated approaches to testing and assessment(IATA)the direct peptide reactivity assay(DPRA)and the human cell line activation test(h-CLAT)were used to detect the preservatives commonly used in cosmetics,including *** paraben,propyl paraben,imidazolidinyl urea and DMDM *** DPRA and the h-CLA were carried out according to the OEC442C and 442E guidelines,*** results show *** and methyl paraben are both negative in DPRA and h-CLAT while imidazolidinyl urea and DMDM hydantoin are both positive in these two *** paraben has negative result in DPRA but positive result in ***,imidazolidiny urea and DMDM hydantoin are sensitizers,while phenoxyethanol and methylparaben are *** animal and human data into consideration,it is predicted that propyl paraben should be a *** combination of DPRA and h-CLAT can make up for the limitations of using a single method,and it is suitable for the preliminary screening of cosmetic raw materials according to skin sensitization.

关键词： Skin sensitization preservative alternative method DPRA h-CLAT AOP

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Degradation of nitrobenzene in wastewater by γ-ray irradiation

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Journal of Environmental Sciences 2004年第3期16卷 364-366页

作者： ZhanG Shu juan 1, FENG Shao hong 1, yu han qing 1,* , LI Qian rong 2 (1 Department of Chemistry, University of Science & Technology of China, Hefei 230026, China. 2 Research Center for Physics & Chemistry, University of Science & Technology of China, Hefei 230026, China) Department of Chemistry University of Science & Technology of China Hefei 230026 China.

The degradation of nitrobenzene(NB) by γ ray irradiation was studied. The influences of dose rate and initial NB concentration were investigated in details. At a dose rate of 55 Gy/min, the degradation kinetics was pseudo first order at NB concentrations from 0 2 mmol/L to 4 0 mmol/L. At an initial NB concentration of 0 8 mmol/L, the degradation of NB at various dose rates also followed pseudo first order kinetics. Dissolved oxygen was found to have a positive effect on NB degradation. The degradation products were identified as nitrophenol, nitrosobenzene, and hydroquinone, and so on. Based on the product analysis, possible degradation pathways of nitrobenzene were proposed.

关键词： degradation irradiation nitrobenzene(NB) kinetics

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Cu^2＋胁迫对黑麦草(Lolium perenne L.)去除富营养化水体中氮、磷效果的影响

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环境科学 2008年第6期29卷 1626-1631页

作者：江凤娟孙庆业李淼俞汉青安徽大学生命科学学院安徽省生态工程与生物技术重点实验室合肥230039 中国科学技术大学化学与材料科学学院环境工程实验室合肥230026

为探讨不同浓度Cu2+胁迫对黑麦草去除富营养化水体中N、P营养盐效果的影响,采用小试培养的方法,研究了Cu2+存在条件下黑麦草对水体中N、P去除的动力学过程及黑麦草植株对不同浓度Cu2+胁迫的生态响应.结果表明,0.1~2.0 mg/LCu2+胁迫均降... 详细信息

为探讨不同浓度Cu2+胁迫对黑麦草去除富营养化水体中N、P营养盐效果的影响,采用小试培养的方法,研究了Cu2+存在条件下黑麦草对水体中N、P去除的动力学过程及黑麦草植株对不同浓度Cu2+胁迫的生态响应.结果表明,0.1~2.0 mg/LCu2+胁迫均降低了黑麦草对水中N、P营养盐的去除速率,其去除过程符合二阶动力学模型.黑麦草对水体中Cu2+亦有良好的去除作用,根部是积累重金属Cu的主要部位,其对Cu2+的吸收速率符合米氏动力学方程.较低浓度Cu2+(≤0.2 mg/L)胁迫对黑麦草去除N、P的效果影响不大,并且能促进黑麦草生物量的增加,而较高浓度Cu2+(≥0.5 mg/L)胁迫虽有促进根系数量增加的趋势,但明显抑制了黑麦草根伸长和叶片生长等作用,因而严重影响了黑麦草对水体中N、P的去除.

关键词：重金属Cu 黑麦草富营养化氮磷

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用厌氧产氢反应器出水培养好氧颗粒污泥的研究

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中国给水排水 2007年第1期23卷 30-33页

作者：郑煜铭俞汉青中国科学技术大学化学与材料科学学院安徽合肥230026

以厌氧产氢反应器出水为底物,在序批式反应器中研究了好氧颗粒污泥的培养过程。结果表明,以厌氧产氢反应器出水为底物,在60 d内能够培养出粒径大、沉降性能优异且对污染物去除能力强的好氧颗粒污泥。在活性污泥的颗粒化过程中,伴随着污... 详细信息

以厌氧产氢反应器出水为底物,在序批式反应器中研究了好氧颗粒污泥的培养过程。结果表明,以厌氧产氢反应器出水为底物,在60 d内能够培养出粒径大、沉降性能优异且对污染物去除能力强的好氧颗粒污泥。在活性污泥的颗粒化过程中,伴随着污泥体积指数的减小,污泥的粒径和沉速增大,反应器内的污泥浓度增加,从而提高了反应器的处理效能。

关键词：好氧颗粒污泥培养厌氧产氢反应器出水序批式反应器

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Ideal Bi‑Based Hybrid Anode Material for Ultrafast Charging of Sodium‑Ion Batteries at Extremely Low Temperatures

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Nano-Micro Letters 2025年第3期17卷 152-167页

作者： Jie Bai Jian Hui Jia yu Wang Chun Cheng Yang qing Jiang Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchun 130022People’s Republic of China

Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or ***,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely ***,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock *** a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1)at 2 A g^(−1))at−60℃,outperforming all reported SIB anode *** with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1)at−40°*** on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.

关键词： Bi nanoparticles High temperature shock High-rate activation Ultrafast charging Low-temperature sodium-ion batteries

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新媒体是否传播了较多的负能量——基于社会公平感知视角

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当代财经 2019年第10期 15-24页

作者：韩雨晴谢强中南财经政法大学经济学院湖北武汉430073 复旦大学经济学院上海200433

利用2015年中国综合社会调查数据,建立随机系数离散选择模型,比较了新媒体和传统媒体的使用频率对社会公平感影响的差异。研究发现:(1)新媒体传播了更多的负能量——新媒体使用频率的提高会降低社会公平感,而传统媒体使用频率的提高会... 详细信息

利用2015年中国综合社会调查数据,建立随机系数离散选择模型,比较了新媒体和传统媒体的使用频率对社会公平感影响的差异。研究发现:(1)新媒体传播了更多的负能量——新媒体使用频率的提高会降低社会公平感,而传统媒体使用频率的提高会提升社会公平感。(2)新媒体使用频率对社会公平感的影响与收入水平有关一收入越高,新媒体使用频率对社会公平感的负向影响越小。(3)新媒体使用频率对社会公平感的影响主要作用于健康人群和城市居民。

关键词：新媒体传统媒体社会公平感

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N掺杂TiO_2光催化剂的制备及其可见光活性研究

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无机化学学报 2005年第11期21卷 1747-1751页

作者：唐玉朝黄显怀俞汉青胡春安徽建筑工业学院环境工程系合肥230022 中国科学技术大学化学与材料科学学院合肥230026 中国科学院生态环境研究中心北京100085

A visible-light-active photocatalyst was prepared by calcination of the hydrolysis product of tetrabutyl titanate with ammonia as precipitant. The photocatalyst was characterized by X-ray diffraction (XRD), UV-Vis diffuse reflection spectra (DRS), thermal gravimetric-differential thermal analysis (TG-DTA), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM). The color of the photocatalyst was yellow and could absorb light wavelength under 550 nm as measured by DRS. The catalyst calcined at higher temperature will give lower absorbance for visible light. Structures of the sample were characterized mainly to be anatase by XRD except for the sample calcined at 700 ℃ which gave mixtures of anatase and rutile. TG-DTA results showed that temperature for anatase formation was 415 ℃. XPS results showed that doped-nitrogen was presented in the sample, they are important to show visible-light absorbency. The photocatalytic activities were evaluated using methyl orange and phenol as model pollutants, the results showed that over 90% of phenol could be degraded under visible light using N/TiO2 as the catalyst after 4 hours reaction. Almost the same activity was found for the TiO2 photocatalyst calcined at different temperature under sunlight but activities were different when the treatment was under UV light.

关键词：光催化 TiO2 N掺杂可见光活性

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基于文献计量分析的土壤侵蚀与土壤有机碳动态研究进展与展望

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土壤通报 2023年第6期54卷 1470-1483页

作者：王洪雨于寒青中国农业科学院农业环境与可持续发展研究所北京100081

【目的】土壤侵蚀引起的土壤有机碳动态变化对可持续土地利用与管理以及陆地碳收支具有重要意义,为了解该领域的前沿及发展方向,采用文献计量学方法探究近30年来土壤侵蚀与土壤有机碳动态研究进展及热点。【方法】本文基于Web of Scienc... 详细信息

【目的】土壤侵蚀引起的土壤有机碳动态变化对可持续土地利用与管理以及陆地碳收支具有重要意义,为了解该领域的前沿及发展方向,采用文献计量学方法探究近30年来土壤侵蚀与土壤有机碳动态研究进展及热点。【方法】本文基于Web of Science核心数据库和中国知网(CNKI)中文核心期刊数据库,采用CiteSpace软件和文献计量学方法,分析了国内外近30年土壤侵蚀与土壤有机碳动态研究的发展历程、研究热点和趋势。【结果】研究表明欧美国家在该领域的研究发展较早,尤其是美国无论是国际影响力还是国际合作紧密性均处于领先地位,我国虽起步较晚但处于稳步快速发展态势;国际上该领域的研究在1995~2004年间主要围绕耕作方式和农艺措施对土壤侵蚀与土壤有机碳动态的影响,进而发展为侵蚀条件下土壤微生物及其群落对土壤有机碳的影响;近十年逐渐向基于稳定性同位素技术的土壤侵蚀与土壤有机碳动态定量研究转变,同时土壤侵蚀导致的碳氮流失所造成的面源污染及侵蚀碳在全球碳循环中的作用也是近年来的研究热点。国内于1995~2004年在本领域的研究主要集中土壤侵蚀所造成的有机碳和养分流失的研究,而后逐渐发展为结合“3S”技术和土壤侵蚀模型,研究人类活动、土地利用及气候变化等因素对土壤侵蚀与土壤有机碳动态的影响。近五年结合核素示踪、光谱等技术,在国家政策引导下该领域逐步发展为从生态综合治理向生态文明建设为核心的问题导向研究。【结论】通过分析对比国内外土壤侵蚀与土壤有机碳动态研究的热点和前沿,提出我国在该领域今后研究的展望。

关键词：土壤侵蚀土壤有机碳动态 CiteSpace 文献计量学

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