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141.
Fire has been considered as an improving factor in soil quality, but only if it is controlled. Severe wild fire occurred in the summer 2007 on the Vidlic Mountain (Serbia) overspreading a huge area of meadows and forests.Main soil characteristics and content of heavy metals (Cu, Pb, Cd, Zn) in different fractions obtained after sequential extraction of soil from post-fire areas and from fire non disturbed areas were studied. In four plant species of Lamiaceae family (Ajuga genevensis L., Lamium galeobdolon (L.) L., Teucrium chamaedrys L., Acinos alpinus (L.) Moench.), that grow in typical habitats of the mountain, distribution of heavy metals in aerial parts and roots was investigated too.For all samples from post-fire area cation exchange capacity and soil organic matter content are increased while rH is decreased. Fire caused slightly increased bioavailability of the observed metals but more significant rise happened in metal amounts bound to oxides and organics. The plants showed variable behavior. T. chamaedrys collected on the post-fire area contained elevated concentrations of all analyzed metals. A. alpinus showed higher phytoaccumulation for Zn and Cd, while the other two plant species for Pb and Cd in the post-fire areas.  相似文献   
142.
成都未来气候变化趋势的R/S分析   总被引:8,自引:0,他引:8  
运用R/S分析法,对1951~2002年成都的平均值气温、极端气温值及降水累积值进行了计算分析。研究表明,成都未来气候变化趋势与过去50年来的变化趋势有着很好的自相似性。今后成都将继续变暖。依平均气候倾向率,未来10年,年平均气温将升高0.25°C,年平均最低气温将升高0.14 °C,年平均最高气温将升高0.04 °C,年极端最低气温将升高0.54 °C,年极端最高气温将升高0.13 °C。其中,年平均气温、年平均最低气温和年平均最高气温升高趋势的持续性强度很强。成都未来降水量将继续减少。未来10年的年降水量将减少45.2 mm,并且这种减少趋势具有很强的持续性强度。  相似文献   
143.
INTRODUCTION: Most studies that evaluate the relationship between economic conditions and traffic fatalities focus on the time-series relationship between the two factors. This analysis considers the cross-sectional perspective by estimating the cross-county correlation between per capita income and fatalities per vehicle mile traveled (VMT) in Ohio. METHOD: The empirical model employed in this analysis allows for interaction effects between per capita income and highway usage, in the determination of fatality rates. RESULTS: The resultant least squares estimates indicate that a significant interaction effect exists between per capita income and the percentage of highway VMT, indicating a nonlinear correlation between per capita income and fatality rates. This correlation rises as the proportion of VMT on highways rises, such that there is an inverse relationship with fatality rates when the highway share of county VMT is low and a direct relationship with fatality rates when the highway share of county VMT is high. Additionally, population density, the presence of interstate highways in rural counties, the prior prevalence of severe alcohol abuse, and the proportion of teen drivers all proved to be significant correlates with county fatality rates. CONCLUSIONS: These observations suggest factors that state and federal policy makers should consider when allocating resources that impact (whether directly or indirectly) traffic fatalities.  相似文献   
144.
邢书才  李风华 《化工环保》2018,38(5):615-620
以铬菁R为显色剂、氯代十六烷基吡啶和曲力通X-100为双组分增敏剂,建立了测定水中Al3+的铬菁R显色分光光度法,并对实验条件进行了优化。实验结果表明:双组分增敏剂的引入,在提高测定灵敏度的同时也增强了测定选择性;在Al3+质量浓度为0.030~0.32 mg/L的范围内,校准曲线的线性关系良好,方法检出限为0.10 mg/L;精密度测定(n=6)的相对标准偏差小于3%,实际样品测定的加标回收率为97.8%~101%。本方法降低了试剂空白值,具有灵敏度高、精密度好、测定范围宽的特点,技术指标优于所有现行国家标准测定水中Al3+的分光光度法。  相似文献   
145.
The impacts of production disruption in Remanufacturing/Manufacturing (R/M) integrated supply chain on the sales and the methods of production disruption management were studied. A system dynamics model for the R/M integrated supply chain with production disruption was improved by system dynamics methodology. The numerical examples were shown to illustrate the simulation results. The impacts of different recovery times of production disruption on the sales were presented. In order to mitigate the disruption risks and ensure the sales at the needed sales ratio, the methods for setting multi-echelon inventory levels before the occurring of the production disruption and the methods for making back-up plans after the production disruption occurs were given.  相似文献   
146.
Abstract

Information regarding the enantioselective endocrine disruption of chiral herbicides is scarce. This study assessed the disrupting effects of eight typical chiral herbicides on corticosteroids (including glucocorticoids and mineralocorticoids). Enantioselectivity of eight chiral herbicides were evaluated for their agonistic/antagonistic effects on glucocorticoid receptor (GR) and mineralocorticoid receptor (MR) with CHOK1 cell line using reporter gene assay. Their influence on the production of corticosteroids were further investigated in H295R cell line using enzyme-linked immunosorbent assay (ELISA). None of the racemates or enantiomers of eight chiral herbicides exhibited GR or MR agonistic activity at non-cytotoxic concentrations. However, rac-propisochlor and S-imazamox antagonized cortisol-induced transactivation of GR by 21.79% and 38.73% at the concentration of 1.0?×?10?7 M and 1.0?×?10?6 M, respectively, and R-napropamide remarkably attenuated aldosterone-induced MR transactivation by 68.78% at 1.0?×?10?6 M. The secretion of cortisol was significantly restrained after treated with 1.0?×?10?6 M rac-propisochlor and rac-/R-napropamide at the concentration of 1.0?×?10?6 M by 26.49%, 30.10% and 35.27%, respectively, while this glucocorticoid was remarkably induced by 1.0?×?10?5 M rac-diclofop-methyl and its two enantiomers at the concentration of 1.0?×?10?5 M by 75.60%, 100.1% and 68.78%, respectively. Exposure to rac-propisochlor (1.0?×?10?6 M), S-diclofop-methyl (1.0?×?10?5 M) or rac-/S-/R- acetochlor (1.0?×?10?6 M) and rac-/S-/R-lactofen (1.0?×?10?6 M) inhibited the secretion of aldosterone by approximately 40%. Our findings suggested that chiral herbicides disrupted corticosteroid homeostasis in an enantioselective way. Therefore, more comprehensive screening is required to better understand the ecological and health risks of chiral pesticides.  相似文献   
147.
山东省区域经济差异趋势研究   总被引:1,自引:0,他引:1  
改革开放以来,山东经济总量稳步扩大,人民生活水平显著提高,2004年以后该省GDP占全国第二,人均国民生产总值名列前茅。一个地区的区域经济发展平衡状况在很大程度上影响着总体经济的发展。从区域经济差异内涵出发,根据基尼系数和R/S分析法对山东省17个区域的经济差异进行了定量评价和趋势预测,提出了区域经济协调对策。  相似文献   
148.
通过构建大中型工业企业研发能力与效率的评价指标体系,运用因子定权法,对河南省18个地市的大中型工业企业研发能力与效率区域差异进行了测度和分析。研究发现,河南省大中型工业企业研发能力与效率整体协调性差,部分地区研发能力的获取是以牺牲研发效率为代价的;自主创新支撑能力、资本投入、环境约束是影响河南省大中型工业企业研发能力与效率的关键因素,而人力资本投入权重相对较小,说明河南省大中型工业企业的研发软实力有待提高。  相似文献   
149.
《海域使用管理法》对中国海洋法制建设具有重要意义。该法施行以来,我国海域使用管理配套法规体系日趋完善,海洋功能区划、海域有偿使用等制度日臻成熟。《海域使用管理法》实施已逾15年,我国经济社会生活发生了巨大变化,中国特色社会主义法律体系不断完善,该法暴露出来的问题日益增多,亟待修订:首先,立法理念应由"重发展,轻保护"向"海域资源和海洋环境保护优先"变革。其次,应完善海域使用权制度,突出海域使用权的物权性,强化该法的私权色彩,将海域使用权的成立时间修改为"完成登记之日"。在围填海管理方面,应理顺围填海建设项目的审批程序,提高行政效率;建立填海造地指标管理制度。最后,在法律责任方面,应明确"恢复原状"的适用条件;修改罚款的计算方法,对于具有持续性的严重海域违法行为可以引入"按日处罚"制度;增加刑事责任条款;赋予海洋行政执法机构必要的行政强制手段。  相似文献   
150.
Correlation relationships of 10 topological indices and molar refraction for 47 structurally-complicated organotins which included 16 ionic compounds RmSnX4-m and 31 covalent ones R4Sn that is 41 aliphatic compounds(15 unsaturated and 26 saturated)and 6 aromatic ones were studied.Suitability of these ten topological parameters for describing the structure of elemental organic compounds was then evaluated according to the correlation results.Two lately improved molecular connectivity indices(MCIs)-radius-corrected MCI 1Xr and bond-length-corrected MCI 1Xb were applied and proved to be most suitable for the structure expression in QSA(P)R studies of organotins or other elemental organic compounds.  相似文献   
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