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111.
为减少弱势人群居家安全伤害事故,采用分析法对某街道社区的医疗伤害监测系统数据进行分析,结合对儿童的问卷调查。结果显示,这个街道老年人、残疾人发生伤害事故比例最高的是跌倒,分析发生伤害的原因,除其身体因素外,缺乏居家安全防护设施及相适应的辅助工具是主要原因;儿童伤害主要是由于缺乏安全知识和好奇心导致。通过有针对性的对老人、儿童、残疾人的安全知识宣传和居家安全设施的改善可以降低伤害事故率。 相似文献
112.
为了研究老化作用对生物炭性质及其对重金属Cd吸附的影响,将浮萍生物炭(LM)分别进行了高温老化(high temperature aging)、冻融循环老化(freeze-thaw cyclesaging)和自然老化(spontaneous aging),通过SEM-EDS、FTIR和吸附实验探究可能存在的变化机理。结果显示:冻融循环老化和高温老化会使生物炭表面O/C分别增加56.98%和90.14%,自然老化比较缓慢,对生物炭O/C影响不大。高温老化使生物炭表面羟基转化为羧基,为羧基化过程;冻融循环老化会使生物炭表面羟基增加,其他官能团基本不变;自然老化条件下,生物炭表面官能团无明显变化。老化作用增强了生物炭对Cd(Ⅱ)的吸附,冻融循环、高温、自然老化作用使LM最大平衡吸附量分别增加了32.67%,83.17%,15.97%。研究表明生物炭的老化会使生物炭本身性质发生变化,但这一变化有利于生物炭对Cd(Ⅱ)的吸附,生物炭在环境中具有较好的稳定性。 相似文献
113.
A multilevel perspective of interpersonal trust: Individual,dyadic, and cross‐level predictors of performance
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While it is generally known that interpersonal trust facilitates individual functioning, few studies have examined the role of specific features of the interpersonal trust network — individual, dyadic, third‐party, and network‐level features — on individual performance. We adopt a multilevel perspective of interpersonal trust to examine how individuals' performance is not only predicted by their individual‐level centrality in the interpersonal trust network but also moderated, at the network level, by the overall centralized nature of that network. Further, we examine whether mutual trust relationships at the dyadic level, as well as shared trust ties to common third parties, can predict individuals' performance. We test our hypotheses with 206 members in 15 professional networking groups and find that interpersonal trust operates at multiple levels to predict members' performance in terms of generating income from business referrals. These findings provide theoretical and practical implications on how interpersonal trust relationships operate and can be managed for performance gains. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
114.
Micheli Dassi Naiéli S. Souto Ana C. M. Braga Mayara L. Freitas Clarissa Vasconcelos Mauro S. Oliveira 《Journal of environmental science and health. Part. B》2013,48(12):840-845
AbstractFu monisin B1 (FB1) is a mycotoxin commonly found in maize and maize-based products. Ingestion of FB1-contaminated causes a myriad of dose- and species-dependent toxic effects to human and animal health. In the present study we evaluated the effects of FB1 (8?mg/kg, i.p. for 4?days) on body weight and oxidative stress parameters in the liver, kidney and lung of C57BL/6 male mice. No changes in the organ-to-body weight ratio, organ-to-adrenal gland weight ratio or organ-to-brain weight ratio were found. On the other hand, FB1 exposure increased NPSH levels in liver and lungs whereas decreased FRAP content in liver and kidneys. Levels of TBARS, ascorbic acid and NOx content were not altered by FB1. In summary, four days of FB1 exposure are sufficient to disrupt antioxidant defenses in liver, kidneys and lungs of C57BL/6 male mice without concomitant changes in organs weight. 相似文献
115.
Local Biodiversity Action Plans are the preferred policy mechanism for setting and delivering local biodiversity targets in the UK. This paper reviews the kind of knowledge conservation scientists envisage being used to identify and set local targets, and explores the means of incorporating local knowledge into this process. We use a case study of a Wildlife Enhancement Scheme (WES) on the Pevensey Levels, East Sussex, to reveal the understandings that local farmers and residents have of the nature conservation goals and practices associated with the scheme. Drawing on the findings of in-depth discussion groups, we show how farmers challenge both the monopoly of knowledge conservationists profess about nature, and the enlistment of farmers on the scheme as «technicians», motivated solely by financial rewards, rather than as knowledgeable experts who also have emotional attachments and ethical values for nature. Local people use their knowledge of both local farmers, and the industry in general, to challenge the assumption that farmers can be trusted with delivering nature conservation goals. In the absence of a commitment by central government to agree widely-held environmental standards, and a more democratic process of making judgements about what local nature is worth conserving, local residents challenge existing processes designed to conserve nature that are driven by the knowledge and practices of official experts alone. The findings of the study suggest that a widening of the knowledge base on which the goals and practices of nature conservation are founded, and a more deliberative process of making decisions about what nature is important locally, will secure and strengthen public support for local biodiversity action plans.1998 Academic Press 相似文献
116.
Climate change vulnerability is disproportionately distributed between different population segments in society. This study qualitatively explores how key stakeholders in municipalities (i.e. planning and operational staff in municipalities and the vulnerable themselves) construct social vulnerability in relation to climate change with a specific focus on thermal stress (i.e. heat waves) and which adaptive responses they identify at different levels. The empirical material consists of five focus groups with actors in a large Swedish municipality where the “Vulnerability Factor Card Game” was used as stimulus material to create 10 fictional individuals. The results show that there is a substantial amount of local knowledge about vulnerability drivers and inter-relations between social factors and vulnerability. Local decision-makers also defined a wide range of possible adaptation measures at different municipal levels. Our study clearly indicates that contextualised knowledge, which could complement the quantitative approaches in research, is abundant among municipal planners, staff employed at municipal operations such as health care, and among the vulnerable themselves. This knowledge remains untapped by research to a great extent and only seems to have an insignificant influence on policy-making. In particular, how impacts vary between different social and demographic groups and how adaptation strategies that target the most vulnerable could be defined are of great interest. The present study clearly indicates that social hierarchy may produce increased inequality in the specific context of climate change, vulnerability and adaptive responses at different levels. 相似文献
117.
A novel material, aminopropyl-functionalized manganese-loaded SBA-15 (NH2-Mn-SBA-15), was synthesized by bonding 3-aminopropyl trimethoxysilane (APTMS) onto manganese-loaded SBA-15 (Mn-SBA-15) and used as a Cu2 + adsorbent in aqueous solution. Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction spectra (XRD), N2 adsorption/desorption isotherms, high resolution field emission scanning electron microscopy (FESEM) and X-ray photoelectron spectroscopy (XPS) were used to characterize the NH2-Mn-SBA-15. The ordered mesoporous structure of SBA-15 was remained after modification. The manganese oxides were mainly loaded on the internal surface of the pore channels while the aminopropyl groups were mainly anchored on the external surface of SBA-15. The adsorption of Cu2 + on NH2-Mn-SBA-15 was fitted well by the Langmuir equation and the maximum adsorption capacity of NH2-Mn-SBA-15 for Cu2 + was over two times higher than that of Mn-SBA-15 under the same conditions. The Elovich equation gave a good fit for the adsorption process of Cu2 + by NH2-Mn-SBA-15 and Mn-SBA-15. Both the loaded manganese oxides and the anchored aminopropyl groups were found to contribute to the uptake of Cu2 +. The NH2-Mn-SBA-15 showed high selectivity for copper ions. Consecutive adsorption–desorption experiments showed that the NH2-Mn-SBA-15 could be regenerated by acid treatment without altering its properties. 相似文献
118.
119.
碳纳米管负载纳米四氧化三铁多相类芬顿降解亚甲基蓝 总被引:5,自引:3,他引:2
在课题组前期研究的基础上,以碳纳米管(MWCNTs)为载体制备了Fe3O4/MWCNTs复合物并作为催化剂,以染料亚甲基蓝(MB)为降解对象,研究了该催化剂催化H2O2对亚甲基蓝溶液的降解特性及其影响因素,并考察了催化剂的重复使用效果,探讨了催化反应的机理.结果表明,在pH值3~8的范围内,催化反应体系都能有效降解MB,最佳pH值为3.5.随着催化剂投量的增加,MB的降解率明显提高,500 mg·L-1催化剂投量条件下,MB的降解率最高.随着H2O2初始浓度的增加,MB的降解率增加,10 mmol·L-1时MB的降解率最高.溶液中共存的阴离子会降低MB的降解率.在最佳条件,即温度25℃、H2O2浓度10 mmol·L-1、催化剂浓度500 mg·L-1的条件下,0.20 mmol·L-1MB在30 min内的降解率达到99.1%.催化剂重复使用后仍然具有较好的催化活性,说明Fe3O4在MWCNTs表面负载比较牢固,催化剂具有反复使用的能力.催化反应机理是催化剂催化H2O2产生羟基自由基,高活性的羟基自由基氧化MB. 相似文献
120.
Ordered mesoporous carbon supported iron catalysts(Fe/OMC) were prepared by the incipient wetness impregnation method and investigated in Fenton-like degradation of 4-chlorophenol(4CP) in this work. XRD and TEM characterization showed that the iron oxides were well dispersed on the OMC support and grew bigger with the increasing calcination temperature. The catalyst prepared with a lower calcination temperature showed higher decomposition efficiency towards 4CP and H2O2, but more metals were leached. The effect of different operational parameters such as initial pH, H2O2 dosage, and reaction temperature on the catalytic activity was evaluated. The results showed that 96.1% of 4CP and 47.4% of TOC was removed after 270 min at 30°C, initial pH of 3 and 6.6 mmol/L H2O2. 88% of 4CP removal efficiency was retained after three successive runs, indicating Fe/OMC a stable catalyst for Fenton reaction. 4CP was degraded predominately by the attack of hydroxyl radical formed on the catalyst surface and in the bulk solution due to iron leaching. Based on the degradation intermediates detected by high performance liquid chromatography, possible oxidation pathways were proposed during the 4CP degradation. 相似文献