25 research outputs found

    Photoreduction of Se(Ⅵ) by Marine Algae-Transitional Metals-Light System

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    以海洋绿藻(Tetraselmislevis,Chlorellaautotrophica,Dunaliellasalina,Nannochloropsissp.,Tetraselmissubcordi-formis)、硅藻(Phaeodactylumtricornutum)、红藻(Porphyridiumpurpureum)和过渡金属(铁、锰、铜)构建海藻-光二元体系、过渡金属-光二元体系、海藻-过渡金属-光三元体系,对比分析不同海藻、不同过渡金属、海藻与过渡金属耦合引发光化学过程,对Se(Ⅵ)还原转化的贡献率.二元和三元体系均可光还原转化Se(Ⅵ)为Se(Ⅳ).铁、铜、锰通过自身的光氧化还原过程诱发Se(Ⅵ)/Se(Ⅳ)的氧化还原;海藻的光化学活性首次被证实,表面壁可吸附富集海水中还原性的有机物、Se(Ⅵ)/Se(Ⅳ)和过渡金属,改变其氧化还原电位,提供光反应场所;Se(Ⅵ)的光还原转化率依海藻和过渡金属的种类、浓度不同而异;海藻浓度的提高、海藻与过渡金属的耦合作用有利于光还原转化率的提高.通过三元体系的光还原转化,Se(Ⅵ)/Se(Ⅳ)比值为1·17~2·85,接近海洋真光层Se(Ⅵ)/Se(Ⅳ)实际浓度比,即海藻和过渡金属引发的光化学过程对硒的价态分布起决定性作用.Seven marine phytoplankton, including five green algae (Tetraselmis levis, Chlorella autotrophica, Dunaliella salina, Nannochloropsis sp. and Tetraselmis subcordiformis), one diatom (Phaeodactylum tricornutum), one red alga (Porphyridium purpureum), and three usual transitional metals (Fe(Ⅲ), Cu(Ⅱ), Mn(Ⅱ)) were used to make up marine phytoplankton-light or transitional metals-light or marine phytoplankton-transitional metals-light system. In such system, Se(Ⅵ) could be transformed into Se(Ⅳ) by photoreduction. The species transformation of selenium could be photo-induced by redox reaction of transitional metals. The photochemical activity of marine phytoplankton was confirmed for the first time, because marine phytoplankton could adsorb and concentrated of selenium, transitional metals and organic substances (including the exudation of algae, as reducing agent) which redox potentials were changed. The ratios of Se(Ⅵ) to Se(Ⅳ) were dominated by the species, the concentration of marine phytoplankton and transitional metals, and it could be enhanced through increasing the concentration of marine algae or the combined effect from marine algae and transitional metals. After photoreduction by ternary system, the ratio of Se(Ⅵ) to Se(Ⅳ) ranges from 1.17 to 2.85, which is close to the actual value in euphotic layer of seawater. The photochemical process that is induced by marine algae and transitional metals dominative the leading effects on the distribution of oxidation states of selenium.国家自然科学基金资助项目(40131160735);; 福建省科技三项费用项目(K02093);; 福建省青年科技人才创新项目(2003J035);; 福建省教育厅A类项目(JA00233

    Neural Basis and Effects of Empathy on Prosocial Behaviors

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    亲社会行为是指那些使他人获益的行为, 这类行为具有重要的进化意义和现实意义。作为影响亲社会行为的重要因素, 共情在认知神经科学领域得到了广泛研究。脑岛等脑区的激活与消极情绪体验有关, 是情绪共情的神经基础, 利于产生亲社会行为动机; 颞顶联合区等脑区参与对他人意图的理解, 是认知共情的神经基础, 利于个体选择有效方式帮助别人。女性在共情时激活额下回等与情绪有关的脑区, 而男性在共情时激活颞顶联合区等与认知有关的脑区, 这为男女个体在亲社会行为表现上的差异提供了新证据。未来研究应完善与亲社会行为有关的脑区功能的解释, 综合多种影响因素, 结合病理学研究考察共情对亲社会行为的影响及神经基础

    亲社会行为产生机制的理论演进

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    亲社会行为是指人们在社会交往中表现出来的谦让、帮助、合作、分享,甚至为了他人利益而做出自我牺牲的一切有助于社会和谐的行为及趋向。亲社会行为的产生机制一直是社会心理学的研究热点,研究者们不断提出各种理论、模型解释亲社会行为。本文通过对亲社会行为理论的梳理,将其按照发展顺序概括为进化理论阶段(亲缘选择理论、群体选择理论、互惠理论)、认知理论阶段(损失-奖赏的激励模型、社会信息加工模型、捐赠的二阶模型)、生物基础理论阶段(生物情感理论、脑机制模型)。最后对这些理论进行总结和评论,并提出未来亲社会行为理论可以进一步关注的问题

    The Contrast Effect of the Recipient’s Outcomes on Prosocial

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    亲社会表现是指人们在社会交往中表现出来的谦让、帮助、合作、分享等行为,其影响机制受到广泛关注。本文通过两个研究(分别以大学生和二、四、六年级小学生为研究对象)探讨了受助者结果类型(受助者获得积极结果vs.受助者避免消极结果)对亲社会表现的影响。结果显示:(1)受助者避免消极结果条件比受助者获得积极结果条件诱发成人更高的亲社会意愿和行为;(2)六年级儿童帮助他人避免消极结果的亲社会意愿更强、情绪更积极;(3)相对于帮助他人避免消极结果,二年级儿童更倾向于帮助他人获得积极结果。这些结果说明受助者结果类型影响个体的亲社会表现(包括亲社会行为、亲社会意愿、亲社会情绪),并且这种影响因成人和儿童有所不同:成人和年长儿童表现出亲社会损失规避现象,年幼儿童则表现出相反效应

    Theoretical Development of the Underlying Mechanism of Prosocial Behavior

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    亲社会行为是指人们在社会交往中表现出来的谦让、帮助、合作、分享,甚至为了他人利益而做出自我牺牲的一切有助于社会和谐的行为及趋向。亲社会行为的产生机制一直是社会心理学的研究热点,研究者们不断提出各种理论、模型解释亲社会行为。本文通过对亲社会行为理论的梳理,将其按照发展顺序概括为进化理论阶段(亲缘选择理论、群体选择理论、互惠理论)、认知理论阶段(损失-奖赏的激励模型、社会信息加工模型、捐赠的二阶模型)、生物基础理论阶段(生物情感理论、脑机制模型)。最后对这些理论进行总结和评论,并提出未来亲社会行为理论可以进一步关注的问题

    Adsorption Performance on Sn(Ⅱ),Sn(Ⅳ) and Dibutyltin in Water with Nanometer TiO_2

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    采用流动注射-氢化物发生-原子吸收光谱法研究纳米TiO2对Sn(Ⅱ)、Sn(Ⅳ)和二丁基锡(DBT)的吸附作用,探讨在不同pH值、吸附时间、试样浓度和试样体积下,不同用量的纳米TiO2的吸附效果以及试样的洗脱条件和效率。结果表明,Sn(Ⅱ)和Sn(Ⅳ)的浓度≤6.0μg/mL、体积≤500 mL、pH=3.0;DBT的浓度≤0.2μg/mL、体积≤50 mLp、H=4.0,30 mg纳米TiO2对Sn(Ⅱ)、Sn(Ⅳ)和DBT的吸附率≥90.0%。在25℃条件下,纳米TiO2对Sn(Ⅱ)、Sn(Ⅳ)和DBT的饱和吸附容量分别为23.6μg/mg、13.7μg/mg和0.628μg/mg,适用于无机锡和二丁基锡污染的吸附去除及对水中无机及丁基锡的定量富集。用4 mol/L HCl对吸附的Sn(Ⅱ)、Sn(Ⅳ)和DBT进行洗脱,洗脱率达到98%以上,可做为样品分析的前处理方法。 【英文摘要】 The adsorption behaviors about different species of tin(Sn(Ⅱ),Sn(Ⅳ),and dibutyltin) in water on nanosize TiO2 were studied.After adsorption or elution,the concentration of Sn(Ⅱ),Sn(Ⅳ) or dibutyltin(DBT) in filtrate or eluent was determined by flow injection-hydride generation-atomic adsorption spectrometry(FI-HG-AAS).The influenceable factors,including pH value,concentration of adsorbate,absorption time,sample concentration,sample volume and amount of adsorbent were studied.The adsorptive ratio of Sn(Ⅱ),Sn(..

    Combined effect of nitrate and phosphate with organic mercury on the growth of Thalassiosira weissflogii

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    探讨在高营养盐(氮、磷、硅分别为浮游植物生长的营养盐阈值≥40、50、9倍)条件下,氮浓度及氮磷摩尔比值[n(N)/n(P)]变化、汞(甲基汞和乙基汞)对微氏海链藻(Thalassiosi-ra weissflogii)生长的影响。结果表明,高营养盐区海链藻的生长遵循营养盐限制的唯一因子论;氮浓度和氮磷比提高促进生长,当n(N)/n(P)=64则呈抑制效应;生长初期,甲基汞和乙基汞均产生毒性抑制作用,生长中后期,适量甲基汞(浓度≤1.0μg/L)、乙基汞(浓度≤0.5μg/L)却呈兴奋效应,促进生长;汞形态不同,剂量-效应关系不同。氮和有机汞是海链藻生长的刺激因子。适度有机汞污染与氮富营养化对微氏海链藻的生长产生协同效应。 【英文摘要】 Thalassiosira weissflogii was cultured in seawater with high levels of nitrate,phosphate,and silicate.The concentrations exceeded the threshold growth limit of marine phytoplankton in 40,50,and 9 times respectively.The influences of different concentrations of nitrate,the ratio of nitrate to phosphate((N/P),) and organic mercury on the growth of T.weissflogii were investigated.The growth was not limited by N/P in the contaminated seawater.The cell densities of T.weissflogii were determined microscopically w...国家自然科学基金资助项目(40131160735);; 福建省科技三项资助项目(K02093);; 福建省青年科技人才创新项目(2003J035

    Adsorption Performance of Arsenic(Ⅲ) in Water on Hyperaccumulating Plant-Pteris vittata

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    采用流动注射-氢化物发生-电热石英管原子吸收光谱法研究了超富集植物蜈蚣草对水中As(Ⅲ)的吸附行为。探讨了蜈蚣草的前处理方法、溶液pH值、吸附时间、吸附剂用量、As(Ⅲ)浓度和溶液体积等因素对蜈蚣草吸附As(Ⅲ)的吸附率的影响。结果表明,以50 mg经2 mol.L-1HCl洗脱处理后的蜈蚣草粉末为吸附剂,在pH为2.0、As(Ⅲ)浓度为20 ng.mL-1、溶液体积50 mL、吸附时间15 min条件下,蜈蚣草对As(Ⅲ)的吸附率可达86.1%,水中残余As(Ⅲ)仅为2.8 ng.mL-1。本法成本低廉、操作简便,可望直接用于地下水中As(Ⅲ)的去除。The adsorption performance on As(Ⅲ) in water with Pteris vittata(hyperaccumulating plant) was studied.The concentration of As(Ⅲ) in water was determined by flow injection-hydride generation-atomic adsorption spectrometry(FI-HG-AAS).The influence factors,including the pre-treatment of Pteris vittata,pH value,concentration of adsorbate,sample volume,adsorption time and amount of adsorbent were studied.The adsorption ratio of 20 ng/mL As(Ⅲ) with Pteris vittata(L) which was pre-treated by 2 mol/L HCl was 86.1% and the residual concentration of As(Ⅲ) was reduced to 2.8 ng/mL under the optimum conditions.The method was economical,manipulated simple and convenient,which could be used to remove As(Ⅲ) of groundwater directly,and met the standards of drinking water made by EU,EPA and WHO.国家自然科学基金(No.40506020

    东楮岛海草组织碳氮含量特征及环境影响因素

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    海草组织碳氮含量可快速响应外界环境影响,已经广泛用于海草生态系统健康评估的指示因子。2011—2012年对东楮岛大叶藻海草床进行4次采样调查,研究了不同季节海草组织碳氮含量特征,分析了环境因素对大叶藻组织碳氮含量的影响。结果表明:海草组织碳、氮含量有明显季节性变化。海草叶碳含量最大值出现在5月,为36.4%,最小值出现在12月,为30.8%;而海草叶氮含量最大值和最小值分别出现在2和5月,为2.73%和2.02%。环境因素的相关性分析表明,海水温度对海草叶碳含量和根氮含量具有显著影响,海水及沉积物间隙水中的氮营养盐对海草茎、叶中的碳含量和根、叶中的氮含量有显著影响。调查表明东楮岛海域海草组织氮..
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