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871.
改革开放以来,我国城市园林绿化事业虽然取得了长足进展,但仍面临着人多地少、资金严重缺乏的窘境,本文分析了产业这些问题的症结,提出了相应的对策与建议。 相似文献
872.
陈杰 《湖南环境生物职业技术学院学报》2003,9(3):233-237
当今全球环保思潮的冲击和绿色消费的方兴未艾,企业如果沿袭传统的营销方式,必将被淘汰.企业要想生存发展,并在竞争中立于不败之地,必须适应新的形势,改弦易辙,实施绿色营销,以满足人们的无污染、无公害、延年益寿的需求.本文讨论了绿色营销的现状及其对企业发展的影响,并提出了实施绿色营销的战略对策. 相似文献
873.
在调研了上海化学工业生产工艺的基础上,结合将来上海化学的原料和产品,着重提出了一些清洁生产工艺的建议和规划。在异氰酸酯、甲基丙烯酸甲酯、叔丁胺、苯胺、亚氨基二乙酸、碳四、苯二酚等项目方面提出了相应的建议。 相似文献
874.
Two inhibitors, triethanolamine (TEA) and monoethanolamine (MEA), were tested for their ability to prevent the de novo formation
of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) on sinter plant fly ash. The amounts of both PCDDs and PCDFs, formed
by thermal treatment of the fly ash, decreased when inhibitors were added. Up to 90% reduction of the PCDD/Fs formation was
reached when 2 wt % monoethanolamine was mixed with fly ash. The temperatures tested, 325 and 400 °C, did not affect the inhibition
activity. However, a longer reaction time, 4 h instead of 2 h, gave higher percentages of PCDD/Fs reduction. The laboratory
results show that ethanolamines reduce the dioxins formation on sinter plant fly ash under various conditions of temperature
and reaction time. Moreover, factory tests performed in parallel at a sinter plant are in good agreement with the laboratory
experiments, thus confirming that the use of ethanolamine inhibitors is an appropriate technique for the prevention of dioxins
emissions from sintering processes.
Electronic Publication 相似文献
875.
When petroleum hydrocarbons contaminate soil, the carbon:nitrogen (C:N) ratio of the soil is altered. The added carbon stimulates microbial numbers but causes an imbalance in the C:N ratio which may result in immobilization of soil nitrogen by the microbial biomass, leaving none available for plant growth. As members of Leguminosae fix atmospheric nitrogen to produce their own nitrogen for growth, they may prove more successful at growing on petroleum hydrocarbon contaminated sites. During a wider study on phytoremediation of diesel fuel contaminated soil, particular attention was given to the performance of legumes versus other plant species. During harvesting of pot experiments containing leguminous plants, a recurring difference in the number and formation of root nodules present on control and contaminated Common vetch (Vicia sativa L.) plants was observed. The total number of nodules per plant was significantly reduced in contaminated plants compared to control plants but nodules on contaminated plants were more developed than corresponding nodules on control plants. Plant performance of Common vetch and Westerwold's ryegrass (Lolium multiflorum L.) was compared to illustrate any difference between the ability of legumes and grasses to grow on diesel fuel contaminated soil. Common vetch was less affected by diesel fuel and performed better in low levels of diesel fuel contaminated soil than Westerwolds ryegrass. The total amount of diesel fuel remaining after 4 months in Common vetch planted soil was slightly less than in Westerwolds ryegrass planted soil. 相似文献
876.
大气CO2与植物氮素营养的关系 总被引:6,自引:0,他引:6
大气CO2浓度升高对植物吸收氮素,以及对植物和土壤中的氮浓度、C/N比和氮循环都存在着影响。大气CO2浓度与植物氮素营养之间存在着交互作用。大气CO2浓度升高对植物氮素营养影响的结果与氮浓度、氮形态等因素有关。 相似文献
877.
植物次生代谢:功能、调控及其基因工程 总被引:18,自引:0,他引:18
植物次生代谢物具有多种重要的生物学功能 ,在工农业生产和人们日常生活中具有广阔的应用前景 .随着可持续农业的发展 ,植物次生代谢物的化学生态学功能及其对农产品品质的影响倍受关注 .植物次生代谢调控的生物化学、分子生物学和基因工程已成了当今国际生物界十分活跃的前沿研究领域 .本文仅就植物次生代谢物功能、代谢调控及基因工程研究进行简要的概述 .1 植物次生代谢物的功能1.1 植物次生代谢物的化学生态学功能植物次生代谢物按其合成方式可分为组成型和诱导型两种类型 ,它们在植物与植物、植物与微生物及植物与昆虫之间的关系中行… 相似文献
878.
Galina Belogolova Olga Gordeeva Marina Sokolova Mikhail Pastukhov Olga Vaishlya Vera Poletaeva 《Chemistry and Ecology》2020,36(3):220-235
ABSTRACTThe study was aimed at the migration and transformation of lead compounds in the rhizosphere, its accumulation in plants under the influence of the rhizosphere bacteria. For experiment, soil samples of the technogenous ecosystem contaminated differently by lead have been selected for plant growing. The samples were subdivided into control soil and the soil, inoculated by Azotobacter and Bacillus rhizobacteria. Lead concentrations have been analysed in easily exchangeable, carbonate, organic and Fe hydroxide-associated fractions as well in chelate forms and fulvic and humic acids. In soils, inoculated by rhizobacteria, there is an increased mobilisation of lead due to its decrease in humic acids and increase in fulvic acids. On technogenic soil, rhizobacteria initiate the immobilisation of Fe-hydroxide-bound, chelate-bound lead in the rhizosphere as well as lead occurring in roots. As a results, there is a decreased lead uptake by upper parts of plants. There is also a correlation between increasing soil alkalinity and increasing Pb accumulation in the roots of plants. The results of the experiment helped to understand more about the mechanisms of Pb compound behaviour under the influence of rhizobacteria that can be used for developing biotechnologies related to soil bioremediation and crop production. 相似文献
879.
遮荫处理对4种草本植物生理生化特性的影响 总被引:3,自引:0,他引:3
研究了遮荫处理对少花龙葵、三叶鬼针草、胜红蓟和莶叶片的生理生化特性的影响,结果表明:遮荫处理提高了4种草本植物叶绿素a b含量,叶绿素a/b存在物种差异;4种草本植物叶片最大净光合速率(Pn-max)、光饱和点(LSP)和光补偿点(LCP)均明显下降;少花龙葵叶片MDA和POD含量降低,三叶鬼针草、胜红蓟和莶升高;遮荫处理使少花龙葵、三叶鬼针草和胜红蓟叶片可溶性糖含量增加,可溶性蛋白含量均呈不同程度下降。少花龙葵耐阴性较强,适度遮荫利于少花龙葵生长发育;三叶鬼针草、胜红蓟和莶受到弱光胁迫。 相似文献
880.
克隆植物的碳素生理整合及其生态学效应 总被引:1,自引:0,他引:1
碳素整合是克隆植物生理整合过程中非常重要的一部分,是克隆植物生存、生长、繁殖的物质基础.克隆植物碳素整合的基本机制具有一定的共同性或相似性,但克隆植物的种类不同、所处生境以及发育阶段不同或所受到的干扰、胁迫的程度不同,其碳素整合的范围、强度、方向、过程等也有所差异.本文对克隆植物碳素生理整合的基本特征、生态效应以及主要的影响因素进行了详细分析,并对迄今有关克隆植物碳素整合的最新研究进展进行了系统总结.同时,对碳素整合的主要研究方法进行了评价与展望,认为在今后研究中,应加强对克隆植物碳素整合的遗传学基础的研究,同时对于碳素整合的生理学、解剖学和生态学机制的研究也亟待深入. 相似文献