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101.
102.
Marija Sarić-Krsmanović Jelena Gajić Umiljendić Ljiljana Radivojević Ljiljana Šantrić Ivana Potočnik Rada Đurović-Pejčev 《Journal of environmental science and health. Part. B》2019,54(4):247-251
The evaluation of the inhibition effect exerted by the essential oils of basil (Ocimum basilicum), sage (Salvia officinalis), thyme (Thymus vulgaris), lemon balm (Melissa officinalis) and goldenrod (Solidago virgaurea) on seeds germination and early seedling growth of velvetleaf (Abutilon theophrasti Medik.) weed was examined in a laboratory bioassay. The essential oils were obtained by hydrodistillation and characterized chemically by gas chromatography coupled with both mass spectrometry and flame ionization detector. The working solutions of essential oil emulsified with Tween 20 and dissolved in distilled water were prepared at three concentration levels (0.01%, 0.1% and 1%, vol/vol). The results obtained showed that increase of essential oil concentration leads to decrease of seed germination, shoot and radical length of velvetleaf. The obtained data revealed a highly significant effect (P?<?0.05) between control and 1% and 0.1% oil concentrations in all treatments. The essential oils of basil, thyme and lemon balm exhibited more powerful bio-herbicidal effect compared to sage and goldenrod essential oils on the germination and early seedling growth of velvetleaf weed. 相似文献
103.
利用拉曼光谱对采样后的滤筒进行分析,发现废气中的硫酸铵-硫酸氢铵气溶胶是造成成都市部分企业烟气排放连续监测系统(CEMS)颗粒物比对监测结果不合格的主要原因。通过比较分析得出:在对含硫酸铵-硫酸氢铵气溶胶废气进行颗粒物浓度比对监测时,参比方法(重量法)测定的颗粒物浓度是一定标干采样体积下废气中固体微粒和硫酸铵-硫酸氢铵液体微粒结晶后产生的晶体的总质量,基于光散射法的CEMS颗粒物浓度测试系统测定的颗粒物浓度只是一定标干采样体积下废气中固体微粒的质量,由此导致参比方法测出的颗粒物浓度远大于CEMS测出的浓度,造成比对误差远超出允许值范围。 相似文献
104.
转炉渣诱导磷酸钙结晶法去除和回收废水中磷的研究 总被引:1,自引:0,他引:1
以转炉渣为晶种材料,利用批次结晶沉淀实验,研究不同的反应条件对诱导磷酸钙结晶法去除和回收废水中磷的影响。结果表明,最优反应条件为:pH=9.5,Ca/P摩尔比2∶1,转炉渣用量1.7 g/L,反应时间3 h,在此条件下,碳酸根对反应的影响甚小,对养猪场废水和污泥浓缩池上清液的处理,最高去除率分别达到95.36%和96.54%;转炉渣循环利用10次,回收磷的效果仍然很好。运用扫描电子显微镜(SEM)、X射线能谱仪(EDS)和X射线衍射仪(XRD)等测试手段对在最优工艺条件下重复使用10次的转炉渣进行了表征,证明回收的磷主要以羟基磷灰石(HAP)形态存在。 相似文献
105.
Vestergaard Peter 《Journal of Coastal Conservation》2001,7(2):117-128
The initial recovery of vegetation after a wildfire in a coastal dune area in NW Jutland, Denmark, was studied over a 5-yr
period by means of permanent plots representing various dune communities along a topographical gradient.
The impact of the fire varied with the position of the plots. Fens and south-facing dunes were little affected while dune
heath plots were severely affected including loss of the O-horizon. Post-fire conditions included presence of remaining soil
organic matter, a soil seed bank and surviving below-ground plant parts. The soil surface remained stable during the study
period.
The initial five years of recovery comprised of an initial three-year recruitment phase during which cover and number of species
increased and the quantitative species composition changed markedly, followed by two years of a declining rate of change.
38 species of vascular plants were recorded, 35 are regular components in dune, dune heath and heath fen and were recruited
from the seed bank, from locally dispersed seeds and/or by sprouting from surviving vegetative parts. The remaining three
species were ‘aliens’, dispersed from sources outside the area. Crustose lichens had an important role in the initial recovery
by stabilizing the surface and probably inhibiting seed germination, whereas mosses mostly had a subordinate role.
The seral position of the plots, as well as the expected time needed for full recovery of pre-fire vegetation, vary with topography
and initial soil conditions. Five years after the fire the fen and the south-facing dune probably need less than a decade
for full recovery. The remaining plots are judged to be relatively early seral; their full recovery into mature dry or moist
dune heath vegetation and O-horizon is expected to need several centuries. 相似文献
106.
2006年秋冬两季图们市大气气溶胶中多环芳烃分布规律 总被引:1,自引:0,他引:1
大气气溶胶是目前大多数城市的首要污染物,其中的多环芳烃是对人体健康危害最大的环境污染物之一。通过图们市2006年9月、12月4个采样点的大气气溶胶样品分析,研究了大气气溶胶中多环芳烃的分布规律。采用超声波萃取法提取样品中的多环芳烃,然后对其进行旋蒸浓缩,氮气吹至1ml,用高效液相色谱进行定性和定量分析。实验结果表明,美国EPA优先控制的16种多环芳烃普遍存在于图们市区的大气气溶胶中。图们市不同时空大气气溶胶中多环芳烃的分布具有一定的规律性。 相似文献
107.
R. A. Chapman C. R. Harris J. H. Tolman D. Dubois C. Cole 《Journal of environmental science and health. Part. B》2013,48(2):233-245
Abstract Potatoes were grown from cut seed in Plainfield sand treated in‐furrow with disulfoton (Di‐Syston 15G, 3.36 kg Al/ha) in 1983 and from whole seed in similarly treated loam in 1991. Soils were contained in 2 m2 field plots. Soil, seed potato and foliage were analyzed for the insecticide and its sulfoxide and sulfone metabolites during the 8–12 wk following planting. Disulfoton disappeared at different rates from the two soils (ksand=0.024 day‐1, kloam=0.056 day‐1) with partial conversion to the sulfoxide and sulfone in both. Larger quantities of the three insecticidal components were absorbed by the seed potato in the cut‐seed/sand combination. The relative amounts of these components in the seed potato also differed between treatments with disulfoton being the largest component of the cut‐seed/sand and smallest in the whole‐seed/loam. Disulfoton sulfoxide and sulfone were the major insecticidal components of the foliage and concentrations in the initial foliage (each ca. 10 ppm) were similar for both treatments. Sulfoxide concentrations in the foliage decreased more rapidly than the sulfone and the decrease in concentration of each of the components was similar for the two treatments. 相似文献
108.
采用城市生活污水配水同时启动两组ASBR,R1接种好氧硝化污泥,R2按2∶1混合接种短程硝化和厌氧氨氧化污泥,研究2个ANAMMOX反应器启动的可行性及其差异。实验结果表明,R1和R2均可成功启动ANAMMOX,R1需130 d,R2仅需73 d;稳定期R1和R2反应器NH4+-N、NO2--N和TN去除率分别达95.30%、91.30%、76.28%和96.2%、98.3%、90.1%,且周期内NH4+-N、NO2--N和NO3--N降解规律相似;R1和R2反应器发生的主要反应为厌氧氨氧化,但同时存在反硝化作用;2组反应器稳定运行后污泥颜色、形态及微生物组成相似,经SEM观察多为球状菌。 相似文献
109.
葡萄酒副产品深度利用的研究进展 总被引:1,自引:0,他引:1
介绍了葡萄皮渣、葡萄籽、酒脚的深度利用途径:葡萄皮渣可用于酿酒、酿醋、提取色素和多酚、吸附重金属;葡萄籽可以提取葡萄籽油、葡萄籽蛋白和抗氧化物质;酒脚可以提取酒石酸盐。开展葡萄酒副产品的深度利用,不仅可以获得良好的经济效益,而且可有效减轻环保压力,获得巨大的社会效益。 相似文献
110.
Based on preliminary findings of ongoing 'action research' in the war zone in central Sierra Leone, this paper shows how more equitable seed distribution could contribute to fostering a culture of human rights as well as to agricultural rehabilitation. Assessment of seeds-and-toosl programmes in 19 villages found that aid agency targeting and distribution modalities channelled inputs through village committees which denied assistance to intended beneficiary groups. Such distribution inequalities constitute violations of fundamental human rights, exacerbate grievance and division and maintain the threat of social disorder. The benefits and disadvantages of an alternative, more inclusive, rights-based approach to seed distribution are discussed, and preliminary results from the pilot phase of CARE's Rights-based Approach to Food Security Project are presented. Under this project, village-level peace and rights days are held to allow villagers to debate the vulnerabilities that facilitated the war and to elaborate on local notions of human rights. In symbolising new beginnings, seed can be seen as a useful medium through which to debate a more inclusive--and ultimately less vulnerable--society. 相似文献