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481.
Nowadays, more people tend to spend their recreational time in large national parks, and trace metal(loid)s in soils have attracted long-term attention due to their possible harm to human health. To investigate the pollution levels, potential sources and health risks of trace metal(loid)s in road soils, a total of eight trace metal(loid)s (including As, Cd, Cr, Cu, Ni, Pb, Zn and Hg) from 47 soil samples along roads were studied in the Huangshan National Park in Southeast China. The results showed that the concentrations of As, Cd, Pb, Zn and Hg appeared different degrees of pollution compared with their corresponding background values. According to the pollution indices, Hg and Cd were recognized as significant pollutants presenting moderate to high ecological risk. Combining principal component analysis and positive matrix factorization model, the results showed that traffic, industrial, agricultural and natural sources were the potential origins of trace metal(loid)s in this area, with contribution rates of 39.93%, 25.92%, 10.53% and 23.62%, respectively. Non-carcinogenic risks were all negligible, while the carcinogenic risk of As was higher than the limit (1 10−6). Moreover, children were more susceptible to trace metal(loid)s by ingestion which appeared to be a more important exposure pathway than dermal contact and inhalation. The contribution rates of different sources to non-carcinogenic risks and carcinogenic risks were similar among children and adults, while traffic and industrial sources have a significant impact on health risks. This study will give more insights to control the environmental risks of trace metal(loid)s in national parks. 相似文献
482.
Zhiguo Cao Qiaoying Chen Xiaoying Wang Yajie Zhang Shihua Wang Mengmeng Wang Leicheng Zhao Guangxuan Yan Xin Zhang Ziyang Zhang Tianfang Yang Mohai Shen Jianhui Sun 《Environmental geochemistry and health》2018,40(6):2441-2452
Concentrations of eight trace metals (TMs) in road dust (RD) (particles?<?25 μm) from urban areas of Xinxiang, China, were determined by inductively coupled plasma mass spectrometry. The geometric mean concentrations of Zn, Mn, Pb, As, Cu, Cr, Ni and Cd were 489, 350, 114, 101, 60.0, 39.7, 31.6, and 5.1 mg kg?1, respectively. When compared with TM levels in background soil, the samples generally display elevated TM concentrations, except for Cr and Mn, and for Cd the enrichment value was 69.6. Spatial variations indicated TMs in RD from park path would have similar sources with main roads, collector streets and bypasses. Average daily exposure doses of the studied TMs were about three orders of magnitude higher for hand-to-mouth ingestion than dermal contact, and the exposure doses for children were 9.33 times higher than that for adults. The decreasing trend of calculated hazard indexes (HI) for the eight elements was As?>?Pb?>?Cr?>?Mn?>?Cd?>?Zn?>?Ni?>?Cu for both children and adults. 相似文献
483.
Effects of intercropping with floricultural accumulator plants on cadmium accumulation in grapevine 总被引:2,自引:0,他引:2
Chen Hongqiang Lin Lijin Liao Ming’an Wang Jin Tang Yi Sun Guochao Liang Dong Xia Hui Deng Qunxian Wang Xun Lv Xiulan Ren Wei 《Environmental science and pollution research international》2019,26(24):24474-24481
Environmental Science and Pollution Research - Grapevine (Vitis vinifera L.) intercropping with floricultural cadmium (Cd) accumulator plants (Helianthus annuus L., Cosmos sulphureus Cav., Cosmos... 相似文献
484.
Wang Hong-Yan Chen Peng Zhu Yong-Guan Cen Kuang Sun Guo-Xin 《Environmental science and pollution research international》2019,26(9):8575-8584
Environmental Science and Pollution Research - A novel biochar was prepared by loading birnessite to improve its capability to simultaneously adsorb As(III), As(V), and Cd(II) in water and soil.... 相似文献
485.
Electrocatalytic oxidation of ciprofloxacin by Co-Ce-Zr/γ-Al2O3 three-dimensional particle electrode
Liu Yaxin Ma Yongwen Wan Jinquan Wang Yan Sun Jian Xue Yangyang 《Environmental science and pollution research international》2021,28(32):43815-43830
Environmental Science and Pollution Research - In this work, Co-Ce-Zr/γ-Al2O33 particle electrodes were prepared for the efficient degradation of ciprofloxacin (CIP). Co-Ce-Zr/γ-Al2O3... 相似文献
486.
487.
Multisource data collected at three time phases were used in investigating when servant leadership elicits gratitude and then promotes prosocial behaviors. We tested a moderated mediation model, contending that relational attributions moderate the relationship between servant leadership and gratitude, and then gratitude sequentially predicts interpersonal citizenship behaviors and upward voice. As hypothesized, when employees do not highly rely on relational attributions for servant leadership, they feel more gratitude and subsequently engage in more interpersonal citizenship behaviors and upward voice than the employees who rely on relational attributions to explain their interactions with the leader. The sequential indirect effect from servant leadership to upward voice via gratitude and then interpersonal citizenship behaviors was significant when relational attributions are low rather than high. 相似文献
488.
The distribution, feeding and oxygen consumption of Calanus sinicus were studied in August 2001 on a transect across Yellow Sea Cold Bottom Waters (YSCBW) and two additional transects nearby. The distribution of C. sinicus adults and copepodites stage CV appeared to be well correlated with water temperature. They tended to concentrate in the YSCBW (>10,000 ind. m–2) to avoid high surface temperature. Gut pigment contents varied from 0.44 to 2.53 ng chlorophyll a equivalents (chl a equiv.) ind.–1 for adults, and from 0.24 to 2.24 ng chl a equiv. ind.–1 for CV copepodites. We found no relationship between gut pigment contents and the ambient chl a concentrations. Although the gut evacuation rate constants are consistent with those measured for other copepods, their low gut pigment contents meant an estimated daily herbivorous ingestion of <3% of body carbon in the YSCBW and <10% outside the YSCBW. However, based on estimates of clearance rates, C. sinicus feeds actively whether in the YSCBW or not, so the low ingestion rates probably reflect shortage of food. Oxygen consumption rates of C. sinicus ranged from 0.21 to 0.84 l O2 ind.–1 h–1, with high rates often associated with high temperature. From the oxygen consumption rates, daily loss of body carbon was estimated to be 4.0–13.7%, which exceeds our estimates of their carbon ingestion rates. C. sinicus was probably not in diapause, either within or outside the YSCBW, but this cold-water layer provides C. sinicus with a refuge to live through the hot, low-food summer.Communicated by T. Ikeda, Hakodate 相似文献
489.
用乙基纤维素作膜材将三辛胺(简称TOA)微胶囊化,用于萃取酸性水溶液中的Cr2O7^2-离子。通过搅拌法萃取实验表明,TOA被微胶囊化后对铬离子仍具有较高的萃取速度,实验测定渗透系数为6.78×10^-6m/min,并能有效地防止乳化现象。将微胶囊制备成填充柱对Cr2O7^2-进行萃取实验。对外相水的流速、微胶囊粒径、柱的重复使用次数与萃取容量的关系进行了研究。当粒径为100-200μm,流速为3 相似文献
490.
有机磺酸类化合物的络合萃取研究 总被引:15,自引:0,他引:15
本文以三烷基胺为络合剂,正辛醇,煤油,氯仿,四氯化碳等为稀释剂,测定了络合萃取剂对于对甲基苯磺酸,磺基水杨酸稀溶液的相平衡分配系数,讨论了稀释剂,体系PH值和7301络合剂含量对萃取相平衡分配系数D值的影响,确定了形成的萃合物的组成。 相似文献