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61.
Carcinogenic and mutagenic polycyclic aromatic hydrocarbons (PAHs) generated in coal combustion have caused great environmental health concern. Seventeen PAHs (16 high priority PAHs recommended by USEPA plus Benzo[e]pyrene) present in five raw bituminous coals and released during bituminous coal combustion were studied. The effects of combustion temperature, gas atmosphere, and chlorine content of raw coal on PAHs formation were investigated. Two additives (copper and cupric oxide) were added when the coal was burned. The results indicated that significant quantities of PAHs were produced from incomplete combustion of coal pyrolysis products at high temperature, and that temperature is an important causative factor of PAHs formation. PAHs concentrations decrease with the increase of chlorine content in oxygen or in nitrogen atmosphere. Copper and cupric oxide additives can promote PAHs formation (especially the multi-ring PAHs) during coal combustion. 相似文献
62.
This paper addresses a neglected topic in the knowledge management literature: how the size of a network of actors affects the nature of intra-network social relations and knowledge processes. It makes a theoretical contribution to developing understanding in this area drawing on a range of literatures including practice-based perspectives on knowledge, the literature on the embeddedness of social relations, and relevant knowledge management literature. The central focus of this paper is on the relationship between network size, network density, and how these variables affect intra-network knowledge processes. It suggests that as network size increases network density is likely to decrease (as it becomes problematic for the actors in such networks to retain strong ties with a significant proportion of the network's members), which it will be suggested has significant ramifications for intra-network knowledge processes. This paper concludes by reflecting on the implications of the ideas developed for network-based forms of organizing, and innovation processes. 相似文献
63.
Surapon?TangvarasittichaiEmail author Patcharin?Pingmuanglaew Orathai?Tangvarasittichai 《Indian journal of clinical biochemistry : IJCB》2016,31(4):446-451
Hypertension is the most common cardiovascular risk factor. Lipoprotein(a) [Lp(a)], inflammation, oxidative stress and chronic kidney disease (CKD) exacerbate the response to tissue injury and acts as markers of the vascular disease, especially in glomerulosclerosis. We compared the clinical characteristics of 138 non-diabetes hypertensive women (ndHT) patients with 417 non-diabetes normotensive subjects and tested the association of hypertension with Lp(a), inflammation, CKD and oxidative stress by using multiple logistic regression. BP, BMI, waist circumference, creatinine, Lp(a), inflammation and malondialdehyde levels were significantly higher and CKD state in the ndHT patients (p < 0.05). Multiple logistic regression showed hypertension associated with increased Lp(a), inflammation, ORs and 95 % CIs were 2.52 (1.33, 4.80), 2.75 (1.44, 5.27) after adjusting for their covariates. Elevated serum Lp(a) and inflammation levels concomitants with increased oxidative stress and CKD were the major risk factors associated with hypertension and implications for the increased risk of HT and vascular disease. 相似文献
64.
Evrikleia?Tsagala Maria?KordakiEmail author 《Education and Information Technologies》2007,12(4):281-295
This paper aims to determine the factors affecting the decisions of both male and female secondary school pupils whether or
not to pursue undergraduate studies in Computing. It is based on research conducted in Greece, on a sample of 248 pupils,
135 of whom were female. All were aged 17 and about to decide on their future undergraduate studies. Questionnaires were used,
addressing issues in the following four main categories: a) the reasons pupils chose/rejected Computing, b) how family and
friends, the media and the school environment contribute to their decision, c) how pupils perceived their future after studying
Computing and d) how pupils perceived the profile of a computer professional in terms of gender.
相似文献
Maria KordakiEmail: |
65.
We document some basic facts about how liquids behave in the low gravity of outer space and how this poses challenges to space
scientists and engineers who need to design and test systems that handle fluids in outer space while working in the 1-g environment
on Earth.
N Ananthkrishnan is Director, Coral Digital Technologies (P) Ltd, a Bangalore-based company working in the area of multidisciplinary
simulation and system integration of aerospace, naval and surface vehicles, and in the design and development of autonomous
unmanned/micro air vehicles. 相似文献
66.
日本的国家级教育政策研究机构包括国家级政府主导的公务机关性质的教育政策研究机构、独立行政法人性质的教育政策研究机构和大学或大学附属性质的教育政策研究机构。为了更有助于国家层面教育政策的整体规划和深度推进,日本文部科学省对原有的国家级教育政策研究机构进行了改革重组,强化了其服务于政府宏观教育决策的职能。以代表日本国家级教育政策研究机构的国立教育政策研究所为例,改革后其职能为:准确恰当并且迅速地应对教育行政上的诸多课题;回应教育基层实践的要求,进行全面综合地调查研究;向教育相关者提供教育研究情报信息;开展教育领域的国际性的共同研究;推进与地方政府的教育研究所或研究中心等的共同研究。日本国家级教育政策研究机构的改革与发展,为我国教育政策研究的科学化发展提供了参考和启示。 相似文献
67.
为了满足多元化的公共教育需求,解决公共教育产品短缺和公共教育服务不到位等问题,有必要从治理的视角重新思考政府在公共教育产品与服务中的角色和作用,运用治理的理念和精神变革公共教育服务体制,实现公共教育服务供给主体的多元化、公共教育治理权力的多中心化和公共教育服务结构的多样化。 相似文献
68.
儿童时期是一个人一生奠基的关键时期。30年来,我不懈地追求儿童发展的规律,初步构建了以儿童为主体的、自成体系的情境教育理论框架。情感,让我迈出情境教育的第一步。在此基础上,我提出了情感活动与认知活动结合起来的教育主张,构建了情感与认知结合获得教学高效能的课程范式。在回顾整理情境教学的探索历程中,我概括出情境教学促进儿童发展的五要素,构建了情境教育的基础模式和基础原理,并对情境课程进行了网络构建。回顾情境教育理论构架的历程,我的爱与儿童的情的交融,构成了情境教育理论构架的内核。情是教育的魂,是情境教育的命脉。 相似文献
69.
教师教育由职前为重向职后为重转移成为一种新趋势。在实践转向的新潮流中逐步形成了教师教育新中心。教师本位的确立是教师教育实践化转向的内在要求,以课为本的研修是教师专业发展的立基点,遵循教育实践的内在逻辑是教师教育改革生命力的保证,找回教育情景是教师教育实践化的具体体现。 相似文献
70.
This paper discusses the way in which intellectual capital (IC) can be managed to assist organization to overcome dynamic challenges. An intellectual capital management capability (ICMC) model is developed which permits the management of an organization to realize the potential of IC by measuring the maturity level of its IC. The model is consistent with dynamic capability theory, which suggests leveraging internal and external resources in response to environment changes to sustain competitive advantage. By utilizing in-depth interviews with 25 chief executive officers from firms possessing high IC, this study seeks to inform the readers of the preliminary work and the way in which the maturity level of ICMC can be measured through the development and deployment of dynamic capabilities. The verification and enhancement of the proposed model has also clarified our understanding on the evolutionary path of management capabilities of IC. 相似文献