969 resultados para Phenol hydroxylation


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A settlement inhibition assay using barnacle cyprid larvae, Balanus amphitrite, was developed with Cd2+ and phenol as standard reference toxicants. Mean percentage settlement of cyprid larvae showed a progressive reduction with increasing concentrations of Cd2+ and phenol. A significant reduction in settlement was found when cyprids were exposed to 0.1 mgL(-1) Cd2+ or 10 mgL(-1) phenol. The assay was used to assess the sublethal toxicity of three oil dispersants (Vecom B-1425 GL, Norchem OSD-570 and Corexit 9905) commonly used in Hong Kong waters. Results of this investigation show that the barnacle settlement inhibition assay can be incorporated into the battery of tests currently available for ecotoxicological assessment of marine contaminants. (C) 1997 Elsevier Science Ltd.

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The effects of sublethal concentrations of phenol and cadmium on the phototactic responses of the stage II nauplii of the barnacle Balanus amphitrite were investigated. Increased toxicant concentrations caused a reduction in phototactic responses. Balanus amphitrite nauplii exposed to nominal phenol concentrations of 100 ppm and higher for 1-12 h failed to exhibit phototactic responses, while longer exposure times of 24 and 48 h reduced the lowest observable effect concentration (LOECs) to 80 and 60 ppm, respectively. For cadmium, the LOECs, based on nominal concentrations, for B. amphitrite following 1, 6, 12, 24, and 48 h exposures were 20, 4.5, 4.0, 1, and 0.75 ppm, respectively. The LOECs can be significantly reduced by increasing the duration of exposure to the toxicants. A good relationship exists between the phototactic response and toxicant concentration as well as exposure time. Results of this study indicate that the toxicant-induced reduction in phototactic responses of barnacle larvae can be used in a sensitive, rapid screening test for ecotoxicological assessments. (C) 1997 by John Wiley & Sons, Inc.

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大气CO2浓度升高可以通过植物间接影响土壤生态系统。土壤生态系统的结构和功能改变将影响有机质矿化和营养物质循环,进而可能对CO2浓度升高产生正反馈或负反馈。微生物是土壤生态系统的主体,在对CO2浓度升高的反馈中起着至关重要的作用。本研究以开顶箱系统为平台,采用微生物分子生态学技术和现代酶学技术,通过对长期接受500 ppm CO2的红松幼树、长白赤松幼树和蒙古栎幼树非根际土壤连续两个生长季的测定,系统研究了高浓度CO2对温带森林土壤微生物群落的生物量和微生物活性的影响,检测了土壤微生物群落的结构和功能以及土壤化学性质变化,主要结论如下: (1)高浓度CO2处理提高了土壤有机碳含量。与对照组相比较,红松幼树土壤有机碳含量提高9.4%;长白赤松幼树土壤提高0.6%;蒙古栎幼树土壤提高1.3%。 (2)高浓度CO2处理使土壤磷酸酶(phosphatase)、几丁质酶(1,4-β-acetylglucosaminidase, 1,4-β-NAG)和多酚氧化酶(phenol oxidase)活性发生了显著变化,高浓度CO2使红松土壤 1,4-β-NAG活性提高7-25%,长白松土壤1,4-β-NAG平均活性降低14%,蒙古栎土壤1,4-β-NAG平均活性提高31%。 同时研究还发现,过氧化物酶(peroxidase)和多酚氧化酶(phenol oxidase)活性与微生物量碳和微生物量氮呈显著的正相关。相关分析还显示,土壤湿度与1,4-α-葡萄糖苷酶(1,4-α-glucosidase)活性、 微生物生物量碳和微生物生物量氮呈显著的正相关。 高浓度CO2在不同程度上改变了土壤转化酶活性和脱氢酶活性。高浓度CO2显著提高了红松和长白赤松土壤硝化酶活性;而显著降低反硝化酶活性。 (3)研究发现三种树土壤的真菌和细菌群落存在着季节性演替,并且高浓度CO2熏蒸处理使真菌群落结构发生了显著的变化,表现为一些种群优势度下降,另一些升高。虽然,细菌群落没有如真菌群落变化的明显,但研究中也发现高浓度CO2的确使个别细菌种群的优势度发生了显著改变。 亲缘关系与Calocybe carnea,Magmatodrilus obscurus密切的真菌是红松土壤优势种群,与Humicola fuscoatra关系相近的是长白松土壤的优势种群,并且此三种真菌的季节性变化不显著。研究发现高浓度CO2使红松土壤中亲缘关系与Pachyella clypeata,Cochlonema euryblastum,Lepiota cristata,Eimeriidae sp., Trichoderma sp.相近的种群的丰富度显著提高,使蒙古栎土壤中亲缘关系与Serendipita vermifera,Calocybe carnea种群丰富度显著下降,使蒙古栎土壤中与Candida sp.,Magmatodrilus obscurus和Pachyella clypeata亲缘关系密切种群的丰富度显著提高。 (4)三种幼树叶的原位分解培养429天结果显示,红松和长白松凋落物的β-葡萄糖苷酶(1,4-β-glucosidase)和木糖苷酶(1,4-β-xylosidase)活性随着分解而逐渐增加,而这两种酶在蒙古栎凋落物分解过程中保持相对恒定;高浓度CO2显著影响叶凋落物分解磷酸酶(phosphatase),纤维二糖酶(cellobiohydrolase), 几丁质酶(1,4-β-NAG),多酚氧化酶(phenol oxidase)和过氧化物酶(peroxidase)的活性。研究发现,凋落物的生物化学性质变化能引起分解的微生物群落发生变化,进而引起分泌的胞外酶活性变化,科学印证了大气CO2浓度升高“通过影响凋落物质量进而影响分解叶凋落物的微生物群落的结构和功能”的猜测。 不同凋落物之间酶活性差异显著,真菌和细菌群落结构也显著不同。序列与Hyphodiscus hymeniophilus亲缘关系密切的真菌和亲缘关系与Verrucomicrobia bacterium密切的细菌是长白松凋落分解的最优势种群,序列与Lophium mytilinum亲缘关系密切的真菌是红松凋落分解的最优势种群。 另外,研究还发现,高浓度CO2使参与分解红松凋落物Beta proteobacterium OS-15A亲缘关系相近的细菌种群和与Azospirillum amazonense亲缘关系相近的种群丰富度显著降低;使与Luteibactor rhizovicina亲缘关系相近的种群和与Luteibactor rhizovicina亲缘关系相近的种群显著提高。高浓度CO2使定殖于长白松凋落物上Hyphodiscus hymeniophilus亲缘关系相近的种群和与Bionectria pityrodes亲缘关系相近的种群显著提高,而使与Neofabraea malicorticis亲缘关系相近的种群和与Hyphodiscus hymeniophilus亲缘关系相近的种群显著下降。

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具有1,1,4α-三甲基氢化芴骨架结构的天然三环二萜化合物自然界中不常见。在该类化合物中,Standishinal 具有良好的芳香化酶抑制活性和细胞毒活性。迄今未发现有Standishinal 的全合成报道,因此,我们对Standishinal 的全合成进行了探索,在该过程中得到以下实验结果: 1. 发现MSA/P2O5、MSA 在无溶剂条件下,25 °C 时烷氧基苯即可实现向苯酚的转化,但在CH3NO2 中,温度升高至80 °C 并未发生反应。 2. 烷氧基苯或对溴苯酚与α-环香叶酸在不同温度下以MSA/P2O5、MSA、PPA为催化剂以CH3NO2 为溶剂或以BF3·Et2O为催化剂时均不发生Friedel-Crafts酰化反应。 3. 对溴苯酚与香叶酸在p-TsOH 催化作用下发生了香叶酸向α-环香叶酸环化、α-环香叶酸环与对溴苯酚的酯化,得到了唯一产物α-环香叶酸对溴苯酯,产率68%。 Standishinal is one of tricyclic-diterpenes possessing the uncommon 1, 1,4a-trimethylhydrofluorene skeleton. Standishinal possesses cytotoxic and aromataseinhibitory activities. Till now, no synthesis of standishinal has been reported. Inattempt to synthesize standishinal, the following phenomenon were observed: 1. Alkyloxybenzenes could be transformed into corresponding phenol at 25 °C inthe presence of MSA/P2O5 or MSA under solvent free condition. ButAlkyloxybenzenes are stable in presence of MSA/P2O5 or MSA in CH3NO2 even at 80 °C. 2. Friedel-Crafts acylation of alkyloxybenzenes and p-bromophenol withα-cyclogeranic acid could not be realized under catalysis of MSA/P2O5, MSA or PPAin CH3NO2, or under catalysis of BF3·Et2O without CH3NO2. 3. The reaction of 4-bromaophenol and geranic acid in the presecnce of p-TsOHafforded 4-bromophenol α-cyclogeranoate in which cyclization of geranic acid toα-cyclogeranic acid was followed by esterification of α-cyclogeranic acid with p-bromophenol.

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近年来,随着对作物重茬障碍原因的深入研究,植物的化感作用越来越受到国内外众多学者的重视。花椒(Zanthoxy piperitum.)为芸香科植物,是一种收益早、用途广、价值高的经济树种,是川西干旱河谷地区的重要经济作物,其连作障碍也倍受关注,系统研究花椒化感作用将有助于理解和最终解决花椒连作障碍问题。本文首先通过萃取、层析等方法分离花椒主效化感成分;通过外加不同浓度的花椒叶水浸液研究了对土壤氮素养分循环的影响;研究了花椒叶水浸液对苜蓿生理生化、光合作用、氮素养分吸收的影响,并对外施氮肥对这种化感影响的缓解作用做了研究;研究了花椒化感潜力对全球变化——UV-B增强辐射的响应。主要研究结果如下: 1.用不同极性的有机溶剂对花椒叶水浸液浓缩浸膏萃取、柱层析,结合生物活性检测,分离得到主效化感作用组分的一种化感物质——对甲氧基苯酚。采用该物质纯品进行生物活性检测,证明其具有化感作用。 2.花椒叶水浸液处理土壤30天后,土壤硝态氮、铵态氮、无机氮(硝态氮+铵态氮)与对照相比,随着花椒叶水浸液浓度的增加呈现降低的趋势,其中土壤铵态氮含量显著降低,而硝态氮含量的变化则不显著,无机氮含量也显著降低。土壤脲酶和蛋白酶的活性与无机氮含量的变化趋势相同。随着花椒叶水浸液浓度的增加,氨化细菌数量显著降低,固氮菌的数量变化不显著,硝化细菌和反硝化细菌数量有减少的趋势。60天后,硝态氮含量、铵态氮含量、无机氮随水浸液浓度增加的变化趋势与30天时相似;随着花椒叶水浸液浓度的增加,氨化细菌、固氮菌的数量显著减少,硝化细菌数量、反硝化细菌数量仍呈减少趋势;土壤脲酶、蛋白酶活性与第30天的变化趋势相同。第60天与第30天的结果相比,相同水浸液浓度处理的硝态氮、铵态氮、无机氮均有下降的趋势,但除了25g.L-1水浸液处理的外,其它相同浓度的处理间差异均不显著;除了12.5 g.L的处理外土壤脲酶活性均呈增强的趋势;蛋白酶活性都有不同程度的增加;花椒叶水浸液处理的土壤硝化细菌和反硝化细菌数量呈增加趋势。 3.随着花椒叶水浸液浓度的增加,显著抑制了苜蓿根长、地上地下生物量、叶绿素含量、叶片中可溶性蛋白的含量,净光合速率。苜蓿体内四种抗氧化酶(POD、SOD、CAT、APX) 活性随着水浸液浓度的增加而降低,而丙二醛含量则增加。苜蓿氮初级同化相关酶硝酸还原酶(NR)、谷氨酰合成酶(GS)、谷氨酸脱氢酶(GDH)的活性随着水浸液浓度的增加受到不同程度的影响。总的来说,苜蓿硝酸还原酶、谷氨酰合成酶的活性受到抑制,而谷氨酸脱氢酶活性的变化则比较复杂,根呈先降低后增加的趋势,叶片则无显著变化。外施两种不同浓度的硝酸铵氮肥后,对12.5、25 g.L-1花椒叶水浸液处理的苜蓿化感作用有显著的缓解作用,表现在株高、生物量、光合作用等方面,大多达到与对照(0 g.L-1)未施氮肥无显著差异的水平,而对50 g.L-1水浸液处理的苜蓿幼苗,虽有一定的缓解作用,但这种作用均未达到与对照(0 g.L-1)未施氮肥时无显著差异的水平。 4. UV-B增强辐射处理花椒后,花椒的化感潜力显著增强。花椒叶片内UV-B吸收物质的含量和总酚含量均显著增加。 In recent years, with profound research on the reasons of continuous cropping obstacles, allelopathy received increasing attention to many scholars at home and abroad. Zanthoxy bungeanum as a Rutaceae plant is a high economic value species which gains early and uses widely. Zanthoxylum is an important economic crop in the arid valley of western Sichuan region, and its not even has received much concern for the continuous cropping obstacles. The systematic study of allelopathy of Zanthoxylum will contribute to the understanding and final settlement of this issue. The major allelopathic composition was separated through the extraction, chromatography combined with other methods. The impact on soil nutrient cycling was also studied through the addition of different concentrations of water extracts of Zanthoxylum. Furthermore, the effects of water extracts of Zanthoxylum leaves on alfalfa leaf physiological and biochemical indexes, photosynthesis, soil enzymes and nutrient uptake of nitrogen and the mitigation of allelopathy through using external fertilizer were studied to put forward scientific resolvent for Zanthoxylum continuous cropping obstacles .The response of allelopathic potential of Zanthoxylum to global change - UV-B enhanced radiation was studied . The main findings are as follows: 1. Through extraction with different polar organic solvents on concentrated water extract of Zanthoxylum leaf and then using column chromatography combined with detection of biological activity, one of the main allelopathic components- methoxy-phenol was isolated. The biological activity testing of the pure material of methoxy-phenol proved that it does have allelopathic potential. 2. Thirty days after treating soil with water extract of Zanthoxylum leaf, as compared with the control, the contents of soil nitrate, ammonium, nitrate plus ammonium nitrogen showed a trend of decrease with the increase of the concentration of water extract whereas the content of ammonium nitrogen showed a significant reduction, and the content of nitrate did not change significantly, the content of nitrate plus ammonium nitrogen also showed a significant (P <0.05) redction. The activity of soil urease and protease showed the same trend as the content of nitrate nitrogen plus ammonium nitrogen. With the increase in the concentration of water extract, the number of ammonification bacteria significantly reduced but nitrogen-fixing bacteria did not change significantly and there was a decreasing trend in the number of nitrifying bacteria and denitrifying bacteria. Sixty days after the treatment, with the increase in solution concentration of water extract of Zanthoxylum leaf, the content of nitrate、 ammonium nitrogen, nitrate plus ammonium nitrogen showed a similar change trend to 30 days’; the number of ammonification bacteria, nitrogen-fixing bacteria significantly reduced ; the number of nitrifying bacteria, denitrifying bacteria was still an downward trend; the activity of soil urease and protease showed the same trend as the 30th days’. Compared to the results of the 30th days’, the content of nitrate, ammonium, nitrate plus ammonium nitrogen showed a decrease trend between the treatment of same concentration, but there was no significant difference except the treatment of 25g.L-1 between the same concentration; the activity of soil urease showed enhanced trend except the treatment of 12.5 g.L-1; the activity of protease increased to varying degrees; the number of ammonification bacteria、 nitrifying bacteria and denitrifying bacteria were growing while nitrogen-fixing bacteria reduced.. 3. With the increase of the concentration of water extract of Zanthoxylum leaf, the water extract significantly inhibited the root length, aboveground biomass, content of chlorophyll and soluble protein in leaf and net photosynthetic rate. The activity of four antioxidant enzymes (POD, SOD, CAT, APX) reduced with the increase in concentration of the water extract but the content of MDA increased. The activity of enzymes related to primary nitrogen assimilation such nitrate reductase (NR), glutamyl synthetase (GS), glutamate dehydrogenase (GDH) were subject to different degrees with an increase in the concentration of water extracts. In general, the activity of nitrate reductase, glutamyl synthetase were inhibited, while change in the activity of glutamate dehydrogenase was more complex. The activity of glutamate dehydrogenase in leaf was first reduced and then increase,but did not change significantly in root. After using two external different concentrations of nitrogen fertilizer, there was a significant mitigation in inhibiton in plant height, biomass, photosynthesis, etc. in the treatment of 12.5,25 gL-1 of water extract of Zanthoxylum leaf, and most of these indexes showed no significant difference with the control (0 g.L-1, no external fertilizer was added) .Although there showed a certain degree of ease in the treatment of 50 g.L-1 , there was still a significant difference compared with the control (0 gL-1) in which no external fertilizer was used. 4.The allelopathic potential of Zanthoxylum positively responded to enhanced UV-B significantly. The content of UV-B absorbing compounds and the total phenol also significant increased.

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土壤是人类赖以生存的自然环境和农业生产的重要资源,目前土壤受到干旱和盐胁迫的危害越来越严重。杨树具有适应性强、生长快和丰产等特性,本论文以青杨组杨树为模式植物,研究杨树对土壤干旱和盐胁迫的生态生理及蛋白质组学反应,研究成果可为我国干旱半干旱地区营造人工林、防止沙漠化提供理论依据,也为恢复与重建盐污染地区退化生态系统提供科学指导。主要研究结果如下: 1 青杨不同种对逐步干旱胁迫的响应差异 将来自喜马拉雅山东缘高海拔的康定杨和低海拔的青杨枝条扦插在温室中,用来检测它们对逐步干旱胁迫的响应。研究结果表明来自不同海拔的杨树对逐步干旱胁迫的适应性反应是不一样的。株高、叶片发育、叶片相对含水量、丙二醛、过氧化氢等指标的显著性变化在青杨中比在康定杨中来得早些,而且随着干旱胁迫程度的增加,这些参数的变化越来越明显,尤其是当青杨受到严重干旱胁迫的时候;而可溶性蛋白、可溶性糖、游离脯氨酸、抗氧化酶活力变化在康定杨中来得早一些。与青杨相比,在干旱胁迫下,康定杨仍能保持较好的植株生长和叶片发育;康定杨也能在逐步干旱条件下积累更多的可溶性蛋白、可溶性糖、游离脯氨酸及抗氧化酶活力,但是在丙二醛和过氧化氢含量方面增加的更少些。而且,我们的研究结果表明高海拔的康定杨有更强的耐干旱能力,杨树对干旱胁迫的适应能力与干旱发生的速度、强度、持续时间及两种杨树的海拔有关。 2 干旱胁迫下青杨不同种的蛋白质组学分析 来自青杨和康定杨雌株的枝条扦插在温室中,用来研究它们对干旱胁迫的蛋白质组学反应。采用TCA-丙酮/酚提取法提取总蛋白,并进行双向电泳分析。在每个处理的重复图像中都能检测到1,000 个以上的蛋白点。在青杨中有58 个蛋白在干旱处理后发生显著变化,其中22 个蛋白通过肽指纹图谱成功鉴定。康定杨中有69 个蛋白的表达量发生了显著变化,其中有25 个蛋白通过肽指纹图谱成功鉴定。这些被鉴定的蛋白主要参与了光合作用、氧化还原平衡、信号传导、能量代谢、蛋白质合成等过程。尽管被鉴定的蛋白只占叶片总蛋白的很少一部分,但这些被鉴定的干旱响应蛋白可能对维持植株内部平衡方面有重要作用。 3 青杨的盐胁迫响应 青杨植株分别用 0、50 和100 mM NaCl 溶液进行处理。叶片相对含水量、叶绿素a、b 含量、CO2 同化速率和气孔导度的降低表明叶绿体受到了盐胁迫的影响。过氧化氢、丙二醛含量及电导率的升高表明细胞受到了伤害。可溶性糖、游离脯氨酸含量及抗氧化酶含量的上升增加了植株耐盐胁迫的能力。在每个处理的重复图像中都能检测到1,000 个以上的蛋白点。其中有38 个盐响应蛋白被成功鉴定,有16 个蛋白(点4、10、11、14、15、21、24、26、27、28、33、34、35、36、37 和38)出现在盐胁迫的植株中;3 个蛋白(点10、11 和35)只出现在重度盐胁迫处理中;而1 个蛋白(点1)只出现在对照处理中。2 个蛋白(点1 和2)表达量下降,其余蛋白点表达量都增加。被鉴定的蛋白一部分参与了生理生化反应,而另一部分则在信号传导、蛋白质合成等方面有重要作用。盐胁迫下的生理生化变化及蛋白质组学的联合研究有利于青杨对盐胁迫的适应性分析。 Soil is the indispensable environment for human survival and important resource for agriculture development. Nowadays soil is threatened by drought stress and salt stress. Poplars (Populus spp.) possess some characters such as strong acclimilation, fast growth and great production of biomass. In this study, different species of Populus section Tacamahaca spach were used as model plants to investigate the ecophysiological and proteomic responses to drought stress and salt stress. Our results can provide theoretical evidence for the afforestation and prevention of desertification in the arid and semi-arid areas, and also can supply scientific direction for the reconstruction and rehalibitation of ecosystems contaminated by salinity. The results are as follows: 1 Adaptive responses to progressive drought stress in two contrasting poplar species originating from different altitudes Cuttings of Populus kangdingensis C. Wang et Tung and Populus cathayana Rehd., originating from high and low altitudes in the eastern Himalaya, respectively, were examined during one growing season in a greenhouse to determine the effects of progressive drought stress. The results manifested that the adaptive responses to progressive drought stress were different in these two species from different altitudes. Significant changes in height increment, leaf development, relative water content (RWC), malondialdehyde (MDA) and hydrogen peroxide (H2O2) appeared earlier in P. cathayana than in P. kangdingensis, whereas changes in soluble protein, soluble sugar, free proline and antioxidant enzymes appeared earlier in P. kangdingensis. In addition, changes in these parameters became more and more significant when the drought stress progressed, especially under severe drought stress in P. cathayana. Compared with P. cathayana, P. kangdingensis was able to maintain a superior height increase and leaf development under drought stress. Also, P. kangdingensis possessed greater increments in soluble protein, soluble sugar, free proline and antioxidant enzymes, but lower increments in MDA and H2O2 than did P. cathayana when the cuttings were exposed to progressive drought stress. Our results suggest that P. kangdingensis originating from the high altitude has a better drought tolerance than does P. cathayana originating from the low altitude. Furthermore, this study manifested that acclimation to drought stress are related the rapidity, severity, duration of the drought event and the altitude of two contrasting species. 2 Proteomic responses to drought stress in two contrasting poplar species originating from different altitudes The cuttings from a female clone of P. kangdingensis and P. cathayana were used to determine proteomic response to drought stress, respectively. Total proteins of the leaves were extracted by a combination of TCA-acetone and phenol, and separated by two-dimensional gel electrophoresis. More than 1,000 protein spots were reproducibly detected on each gel. 58 differentially expressed spots were detected under drought stress in P. cathayana and 22 drought-responsive proteins were identified by peptide mass fingerprint. 69 differentially expressed spots were detected under drought stress in P. kangdingensiss and 25 drought-responsive proteins were identified by peptide mass fingerprint. The identified proteins are involved in several processes, i.e., signal transduction, protein processing, redox homeostasis, CO2 fixation and energy metabolism. Although the proteins identified in this investigation represent only a very small part of the poplar leaf proteins, some of the novel drought-responsive proteins identified here may be involved in the establishment of homeostasis in response to drought stress in the woody plants. 3 Responses to salt stress in P. cathayana Cuttings from a female clone of P. cathayana were treated by Hoagland’s solution: 0, 50, 100 mM NaCl, respectively. Salinity significantly decreased the relative water content of leaves, the contents of chlorophyll a and chlorophyll b, CO2 assimilation rate (A) and stomatal conductance (gs) in both salt stress treatments,which suggested the chloroplast was affected by salt stress. The observed increases of H2O2 and malondialdehyde contents and electrolyte leakage suggested that salinity caused cellular damage, whereas the increases in compatible solutes and in the activities of antioxidant enzymes enhanced the salt tolerance. More than 1,000 protein spots were reproducibly detected on each gel, and 38 salt-responsive proteins were successfully identified by peptide mass fingerprint (PMF). 16 spots (spot 4, 10, 11, 14, 15, 21, 24, 26, 27, 28, 33, 34, 35, 36, 37 and 38) absent in the control sample were induced by the salt treatment, and three spots (spot 10,11 and 35) were present only in the severely salt-stressed treatment. The %vol of the differentially expressed proteins generally increased with progressing salt stress, except for the decreased %vol of two proteins (spot 1 and 2) under salt stress and the presence of spot 1 only in the control sample. Some of the novel salt-responsive proteins identified here may be involved in physiological, biochemical response to salt stress in P. cathayana, the other identified proteins play a role in numerous cellular functions, including signal transduction and protein processing. An integrated physiological, biochemical and proteomic approach was used here to systematically investigate salt acclimation in poplar.

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环境突发污染事故给人民生活、经济发展和生态环境造成重大影响,研究污染物泄漏造成河流突发污染事故的应急处理方法十分必要。本论文选取苯酚、苯胺和亚甲基蓝等典型污染物为实验对象,采用吸附容量大、密度与水接近的活性炭纤维(ACF)为吸附剂。在自制的河流模型中,研究了ACF以苯酚、苯胺和亚甲基蓝为典型污染物的吸附过程,考察了吸附剂投加量、污染物浓度、吸附剂比表面积、吸附剂投加方式、水流速度与水质等对吸附速率与吸附效果的影响。实验结果表明,ACF能以较快的速率吸附苯酚、苯胺和亚甲基蓝,吸附率都在95%以上; ACF投加量是影响吸附速率最重要的因素,当一次性投加ACF质量之比为 1:2:4时,吸附速率常数之比近似为1:2:4;污染物浓度对吸附速率的影响显著,浓度较低时吸附速率较高。苯酚初始浓度为7mg·L-1时,经过86分钟的吸附,处理后的浓度可以达到地表水Ⅴ类水中挥发酚的限值要求(0.1mg·L-1);在吸附11分钟左右追加适量的ACF,能够明显提高吸附速率;河水流速和河流中的天然有机物、浊度、河水硬度对ACF吸附都不产生显著影响,这说明ACF作为河流突发污染事故应急处理的吸附剂,有广泛的适应性。在实际河水中,ACF对苯酚的吸附过程与在模拟河水中相似,吸附效果显著。实验结果还表明,ACF对苯酚的吸附是放热反应,符合Freundlich模型和Langmuir模型。事故应急处理后,应该及时将吸附了污染物的ACF打捞上来,有利于进行后续处理。 Emergency environmental pollution accidents pose significant impacts on our living, economic development and ecological environment. The study on the approach of emergency control for the contingency caused by leakage of pollutants in rivers is very necessary. In the experiment, phenol, aniline and methylene blue were selected as representative pollutant and activated carbon fiber (ACF) was selected as adsorbent, which has strong adsorption capacity and similar density to water. In the self-made river model, the effects of ACF dosage, pollutant concentration, ACF surface area, ACF adding ways, water flow rate and water quality on adsorption courses were investigated. The experimental results showed that ACF could adsorb pollutant quickly and effectively. The ACF dosage was the most important factor that affected adsorption rate .When the ACF dosage rate was 1:2:4, the constants of adsorption rate was approximately 1:2:4. The effect of pollutant concentrations on the adsorption rate was notable. Faster adsorption rates were achieved at low pollutant concentrations. Phenol concentration reached the limits of volatile phenol in Category Ⅴ surface water (0.1 mg·L-1) after 86 minutes of adsorption with initial phenol concentration of 7 mg·L-1. After 11 minutes of adsorption, certain amount of ACF was added and the adsorption rate was improved significantly. River flow rate and water quality have little effect on the adsorption rate. The adsorption results obtained in actual river water were comparable with that in simulating river water. The results also showed that, ACF on the absorption of phenol is exothermic reaction, witch matched with the Freundlich model and the Langmuir model. After emergency treatment, the ACF absorbed pollutants should be promptly salvaged for follow-up treatment.