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1.
道路绿化种植抗污染植物模式研究   总被引:9,自引:0,他引:9  
在广州市广花公路黄石路段建立了 3个道路绿化抗污染模式进行研究 ,生长 2年后测定各模式对NOx、CO和TSP等大气污染物质的净化效果。结果表明 ,若植物种类相同、配置方式基本相似 ,则种植密度与净化效果密切相关 ,密度适宜能适当通风的林带的净化效果最好  相似文献   

2.
Enhanced adsorption of arsenate on titanium dioxide using Ca and Mg ions   总被引:1,自引:0,他引:1  
In this study, we report the effects of pH and divalent cations on the adsorption of arsenate (As(V)) by titanium dioxide (TiO2) nanoparticles. The extent of As(V) adsorption on TiO2 decreased with increasing pH due to the decrease of positively charged binding sites on the TiO2 surface. The Langmuir maximum uptake capacity at pH 4 is about three times higher than that at pH 7. Here we show that the relatively low As(V) uptake at circumneutral pH could be substantially enhanced by the addition of common divalent cations such as magnesium and calcium. At a concentration of approximately 7 mM, magnesium and calcium increased the extent of As(V) adsorption from 2.1 to 6.5 and 7.7 mg As(V)/g TiO2, respectively.  相似文献   

3.
以实际建筑物为例,介绍了用层次分析法建立绿色建筑评价模型的过程,并分别用层次分析法和人工神经网络法对实际建筑物进行了评价。评价结果显示,人工神经网络法与层次分析法相对误差不到0.5%,表明人工神经网络法作为一种客观科学的评价方法,应用于绿色建筑的评价,能有效降低主观因素带来的影响,会使结果更具有客观性。  相似文献   

4.
Oocyte maturation, embryo development and expression of apoptotic-specific genes were evaluated in blastocysts of mice treated with titanium dioxide nanoparticles. Female mice received 0, 50 or 100?mg/kg/day titanium dioxide intraperitoneally for five consecutive days. After the last injection, pregnant mare serum gonadotropin and, 48?h later, human chorionic gonadotropin were administered intraperitoneally for induction of ovulation. After 14?h, mice were sacrificed and oocytes were collected. The number of mature oocytes was evaluated and then fertilization was carried out in vitro and the numbers of fertilized and cleaved oocytes and of blastocysts and the expression of Bax, caspase 3, and Bcl-xL genes in blastocysts were evaluated. The number of mature, fertilized and cleaved oocytes and of blastocyst embryos in the experimental groups were not different from control. The expression of Bax and caspase 3 genes was significantly elevated in the experimental groups compared to control, while expression of the Bcl-xL gene was significantly lower in the high dose group. Uptake of titanium dioxide nanoparticles at daily doses of 50?mg/kg and more may affect embryo development by alteration of pro-apoptotic and anti-apoptotic gene expression.  相似文献   

5.
绿色植物对环境有着重要的保护作用.概括而言,绿色植物可以吸收CO2、二氧化硫、氟化氢及其它一些有害气体,同时绿色植物还吸收空气中的灰尘、杀灭细菌以及净化水源.本文详细探讨了绿色植物的环保作用,旨在提高人们对于绿色植物认识和保护意识.  相似文献   

6.
我国绿色饭店建设的现状与对策   总被引:3,自引:0,他引:3  
创建绿色饭店已成为新世纪饭店业发展必然趋势.在我国,饭店的创绿活动已如火如荼的展开.本文从绿色饭店的概念入手,分析建设绿色饭店的意义,总结了我国绿色饭店建设的现状,提出了饭店实施绿色计划所面临的任务和对策.  相似文献   

7.
李明玉  曾凡银  房献宝  王君  宋琳 《生态环境》2010,19(10):2474-2478
用热氧化法制备了TiO2/Ti薄膜电极,并用XRD和AFM对TiO2/Ti薄膜电极的晶形和表面形貌进行了表征。结果表明:热氧化法制备的TiO2主要为锐钛型纳米颗粒,直径在40 nm左右。设计了一种新型双槽光电化学反应器,用于废水的处理。以热氧化法制备的TiO2/Ti薄膜电极为阳极进行光电催化反应,同时以石墨电极为阴极用于产生双氧水,并与紫外光组成UV/H2O2体系。考察了双槽反应器中活性艳红X-3B在不同条件下的降解效果。降解结果表明:在新型反应器的阴阳两极槽中,活性艳红不仅在TiO2/Ti阳极槽中被降解,而且在石墨阴极槽中也得到降解;活性艳红在酸性条件下的降解效果最好;相对于单纯的电化学氧化和光催化,光电化学协同作用对X-3B的降解效果最好。  相似文献   

8.
The kinetics of the photocatalytic degradation of 10 different dichlorophenols and dichloroanilines have been investigated experimentally and theoretically. With the intention of finding certain molecular indices in order to determine the degradation rates of aromatic pollutants, geometry optimizations of the compounds have been performed with the semiempirical PM3 method. The molecular orbital calculations have been carried out by an SCF method using the RHF formalism. The correlations between the apparent first-order rate constants and the calculated molecular properties of the compounds have been examined. Four different structure–activity relationships have been developed expressing the logarithms of the rate constants in terms of the Hammett constants, electron densities of the substituents, the coefficients and the energies of the highest occupied molecular orbitals HOMO, and 1-octanol/water partition coefficients log?K OW.  相似文献   

9.
城市绿地系统景观生态规划探讨   总被引:3,自引:0,他引:3  
从景观生态的角度对城市绿地系统进行规划探讨,能够为绿地系统规划布局提供科学的理论指导。在介绍了对绿地系统规划有重要指导意义的景观生态理论的基础上,以常州市新北区为例,进行实证研究,概括了其绿地现状并指出了其存在一系列问题,进而利用景观生态的基本原理,对本区域的绿地系统进行规划研究。将整个研究地区分成“区域层面、分区层面以及具体规划设计层面”3个尺度层面,并且在每个层面利用景观生态中相关原理分别进行研究,最终形成层次分明、在功能上相互补充、有机联系的绿地系统结构。  相似文献   

10.
《毒物与环境化学》2012,94(3-6):228-243
Abstract

Oxidative removal of toluene using copper and cobalt bimetallic catalysts with varying molar ratios supported on sepiolite was investigated. The catalysts prepared by a deposition precipitation method and were characterized using X-ray diffraction, nitrogen adsorption-desorption, field emission scanning electron microscopy, H2-temperature-programmed reduction, transmission electron microscope, and inductive coupled plasma atomic emission spectroscopy. The species supported on sepiolite are Co3O4, CuO, and CuCo2O4. The activities of the tested catalysts increased in the order 0Co-4Cu/Sep <1Co-3Cu/Sep <4Co-0Cu/Sep <1Co-1Cu/Sep <3Co-1Cu/Sep. The latter exhibiting 90% toluene oxidative degradation at 288?°C within 15?h, having high selectivity towards CO2, and being stable at 300?°C up to 15?h. In conclusion, this study showed that sepiolite has excellent properties as a support.  相似文献   

11.
The aim of the plesent investigation was to study the effect of SiO2 addition on the thermal deactivation of V2O5/WO3/TiO2 catalysts used for NOx pollution abatement. The results suggest that the degradation of the catalytic properties is strongly correlated to the structural ageing which is, in turn, mainly related to the anatase–rutile phase transformation and to the WO3 phase segregation. The addition of SiO2 strongly influences the temperature at which these phenomena occur. In fact, it was found that the introduction of this oxide stabilizes the material, retarding the collapse of surface area, and increases the temperature of the anatase to rutile phase transition.  相似文献   

12.
绿色消费是解决当前中国环境污染的重要战略组成部分,本文研究了对上海市开展的关于绿色消费1200余份调查问卷。研究结果显示:1)人们环境意识和绿色消费意愿普遍提高,98%的受访者愿意为保护环境做出自身行为的改变。2)绿色消费认知参差不齐。对绿色产品的认知渠道不多,绿色产品的标签知晓率低于30%。3)绿色消费意愿强烈但支付能力还有限,82%的消费者愿意购买绿色产品,但支付不能超过同类普通商品10%的额外费用。研究结果还表明:绿色消费与性别、年龄、职业以及学历等具有相关关系。  相似文献   

13.
36种典型除草剂对绿藻的毒性研究   总被引:1,自引:0,他引:1  
近年来,农药对生态系统的初级生产者——藻类的毒性及其生态毒理学研究引起了国内外学者的广泛关注。除草剂在生产中广泛应用,对藻类的毒性作用最强,其毒性效应远高于杀虫剂和杀菌剂。论文选择市场上具有典型代表性的36种除草剂原药,分析解读除草剂在国内的登记情况,以及在作物、旱田和水田的使用情况;明晰对藻类生长抑制急性毒性效应。结果表明:1)除草剂的作用方式和化学类别对绿藻毒性影响显著;对于抑制植物细胞分裂和作用于植物叶绿体的除草剂对绿藻毒性均较高,以人工合成植物生长素为代表的除草剂对绿藻毒性均较低;2)相同作用方式,不同化学类别的除草剂,对单一绿藻的毒性差异明显。在水稻上获得登记的除草剂对藻类毒性整体低于在旱田获得登记的除草剂对藻类的毒性。开展多种农药对水生生态毒性的研究,为农药的合理安全使用、农药在淡水环境中的生态效应评价以及保护淡水生态系统提供科学依据。  相似文献   

14.
城市绿色空间及对城市热岛效应的影响   总被引:43,自引:0,他引:43  
采用遥感技术结合实地测定的研究方法,利用1987年至2001年遥感卫星影像数据,建立了北京市不同年份的城市绿色空间专题图和热岛分布图,分析了13年中北京城市绿色空间及热岛效应的演变特点,评价了城市发展及城市绿化对热岛效应的影响。结果表明:受城市化的影响,14年中北京城市绿色空间变化明显,城市热岛效应也随之发生明显变化;随着城市建设范围的扩大,原有自然植被不断减少,热岛影响范围随之扩大;随着市区内的绿化建设,绿色空间总量增加,热岛效应有缓解的趋势。  相似文献   

15.
Abstract: Developmental instability, measured as fluctuating asymmetry (FA), is often used as a tool to measure stress and the overall quality of organisms. Under FA, it is assumed that control of symmetry during development is costly and that under stress the trajectory of development is disturbed, resulting in asymmetric morphologies. Amphibian emergent infectious diseases (EIDs), such as Ranavirus and chytrid fungus, have been involved in several mortality events, which makes them stressors and allows for the study of FA. We analyzed nine populations of green frogs (Rana clamitans) for the presence or absence of Ranavirus and chytrid fungus. Individuals were measured to determine levels of FA in seven traits under the hypothesis that FA is more likely to be observed in individuals infected by the pathogens. Significantly higher levels of FA were found in individuals with Ranavirus compared with uninfected individuals among all populations and all traits. We did not observe FA in individuals infected with chytrid fungus for any of the traits measured. Additionally, we observed a significant association between Ranavirus infection and levels of FA in both males and females, which may indicate this viral disease is likely to affect both sexes during development. Altogether, our results indicate that some EIDs may have far‐reaching and nonlethal effects on individual development and populations harboring such diseases and that FA can be used as a conservation tool to identify populations subject to such a stress.  相似文献   

16.
城市绿地是改善热环境的重要方式之一,当前研究主要集中于以景观指数衡量的绿地空间形态与热环境之间的关系,较少关注以城市公园为主的绿地内部空间结构对热环境的影响及其规划设计实施的可操作性。基于另一种视角——形态学空间格局分析的7个指标量化绿地空间格局,以武汉主城区的其中25个绿地为研究对象,通过2018年9月15日Landsat 8遥感数据反演地表温度,从绿地的点面、边界、廊道三方面分析绿地空间格局对绿地内部平均温度(T)、降温幅度(ΔT)的影响。结果表明:25个绿地可分为内外降温显著型、内部降温显著型、降温效果一般型、降温能力较弱型4类绿地,它们具有显著差异的空间格局主要集中在核心、孤岛与分支。绿地空间格局对自身温度的影响上,T与核心、孔隙指标显著负相关,与孤岛、分支指标显著正相关,可通过提高绿地核心斑块的集中性、核心斑块内部边界营造、减少破碎化小斑块数量、避免仅一端连接核心斑块的廊道等措施,提高绿地自身的降温效果。环线、桥接以非线性方式影响T,可将二者的比例分别控制在5%、17%以内。绿地空间格局对周围温度的影响上,ΔT与核心指标显著正相关,与孤岛、边缘指标显著负相关。ΔT随边缘、分支指标的增加先快速下降后逐渐趋于平稳,需尽可能避免绿地核心斑块被割裂与出现分支。环线仍以非线性方式影响ΔT,适宜控制其比例在6%。  相似文献   

17.
为了及时掌握衡阳市蔬菜产业发展动态,有效的指导衡阳市蔬菜生产,笔者对2006年衡阳市蔬菜品种及产业发展情况进行了调查,主要是摸清蔬菜品种,找出存在的主要问题,提出了下一步蔬菜品种及产业发展措施,把衡阳市蔬菜生产推向一个新的发展水平.表10,参7.  相似文献   

18.
对合肥环城公园不同地段绿地土壤及地被植物麦冬叶片的氮磷含量进行了调查分析。结果表明土壤全氮含量平均为1.36 g/kg、全磷为1451.89 mg/kg、有效磷为84.57 mg/kg;麦冬叶的氮磷含量平均值分别为17.25 g/kg和2.83 g/kg,氮磷比为6.33。叶片氮磷比与土壤全磷、有效磷含量呈显著负相关,而与土壤氮含量没有显著相关性。基于叶片氮磷计量关系,调查区植物生长明显受到氮限制。  相似文献   

19.
Over 1 million species around the world are at risk of extinction, and conservation organizations have to decide where to invest their limited resources. Cost-effectiveness can be increased by leveraging funding opportunities and increasing collaborative partnerships to achieve shared conservation goals. We devised a structured decision-making framework to prioritize species’ conservation programs based on a cost–benefit analysis that takes collaborative opportunities into account in an examination of national and global conservation return on investment. Conservation benefit is determined by modifying the novel International Union for the Conservation of Nature Green Status for Species to provide an efficient, high-level measure that is comparable among species, even with limited information and time constraints. We applied this prioritization approach to the Wilder Institute/Calgary Zoo, Canada, a nonprofit organization seeking to increase the number of species it assists with conservation translocations. We sought to identify and prioritize additional species’ programs for which conservation translocation expertise and actions could make the most impact. Estimating the likelihood of cost-sharing potential enabled total program cost to be distinguished from costs specific to the organization. Comparing a benefit-to-cost ratio on different geographic scales allowed decision makers to weigh alternative options for investing in new species’ programs in a transparent and effective manner. Our innovative analysis aligns with general conservation planning frameworks and can be adapted for any organization.  相似文献   

20.
微囊藻毒素与孔雀石绿对唐鱼游泳行为的影响   总被引:2,自引:0,他引:2  
鱼类行为能准确地反映环境变化,并且随着污染物浓度的变化而发生改变.采用人工饲养的方法,以对环境毒素敏感的唐鱼(Tanichthys albonubes)作为指示生物,检测了其行为对水体中微囊藻毒素和孔雀石绿的反应.结果表明,唐鱼对0.2μg·L-1的微囊藻毒素即有明显的行为反应,摆尾频率和游泳速度均在30min后显著下降;0.5μg·L-1微囊藻毒素处理下,摆尾频率和游泳速度均在15min后显著下降.0.5mg·L-1孔雀石绿处理下,游泳速度在30min后显著下降,而摆尾频率则无显著性变化.初步推断,以对毒素敏感的唐鱼行为作为标记,用以监测水环境安全是可行的.  相似文献   

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