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41.
中国耕地资源利用的碳排放时空特征及脱钩效应研究   总被引:8,自引:0,他引:8  
研究目的:揭示中国耕地资源利用的碳排放时空分异规律及其与农业经济增长之间的脱钩关系,以期为中国耕地资源低碳化利用政策的制定和推行提供参考。研究方法:IPCC碳排系数法,TAPIO脱钩分析法。研究结果:(1)中国耕地资源利用的碳排放整体上呈现增长趋势,但2010年后增速趋于下降并于2016年开始转入负增长,省际差异不断扩大的同时区域间差异趋于缩小;(2)中国耕地资源利用的碳排放强度总体上处于下降态势,省际和区域间碳排放强度的差异总体上趋于缩小;(3)中国耕地资源利用的不同碳排放源的碳排放量及增速呈现不同的时序波动特征,同时存在明显的地域差异性,其中,化肥是最主要碳排放源;(4)中国2000—2012年耕地资源利用的碳排放与农业经济增长之间呈现以"弱脱钩"为主,但2013—2017年不同省域的脱钩类型及脱钩程度趋于差异化。研究结论:中国耕地资源利用碳排放的时空分异性显著,且与农业经济增长之间不同阶段和不同省域呈现不同脱钩类型,需突出减排重点、实施差异化策略及注重绿色发展等多途径推进耕地资源低碳化利用,提高政策的精准性。  相似文献   
42.
Although enterprises in the informal food sector require energy to transform, cook and process food, energy-use patterns in this sector are not well understood by policymakers and the local-level authorities who regulate their trading activities. This paper reviews relevant literature and presents empirical data collected in Rwanda, Senegal and South Africa on the use of traditional and modern energy sources by informal food sector operators. Our sample includes male- and female-operated enterprises in the urban centres of three African countries where the informal food sector is important, not only for providing the convenience of affordable and readily prepared meals, but also as a source of income for women and men in developing countries. Multiple fuel-use and energy-stacking strategies are common among informal food enterprises and policy needs to acknowledge this if it is to intervene in ways that will benefit both enterprises and regulators.  相似文献   
43.
为了研究网架结构的损伤检测方法,根据应变能密度理论,提出采用单元模态应变能密度差值作为网架结构损伤识别指标的方法,以损伤单元模态应变能密度差值的大小初步确定单元的损伤程度。分析了5种具有代表性的损伤工况,并在数值计算结果中引入了白噪声。结果显示,在一阶模态下,针对单损伤、多损伤和轻微损伤、严重损伤等不同损伤工况,损伤杆件的模态应变能密度差值均为高值。因此,该方法可以有效识别出网架结构的损伤位置,根据损伤单元的模态应变能密度差值大小初步确定单元的损伤程度,且在一定的噪声水平下具有较强的鲁棒性,对网架结构损伤识别具有参考价值。  相似文献   
44.
Majority of the increase in global energy consumption is from China; hence, studying energy issues, especially in China’s manufacturing industry (CMI), is worthwhile and of much interest in the academic field. Based on the translog cost function, we develop a research framework to study the rebound effect of CMI. Considering the effect of asymmetric energy price, we augment the energy-cost function with asymmetric influence constraint of energy price. Again, we add time series data of CMI’s capital, labor, energy, and mid-input to the model to calculate the direct rebound effect of CMI. We find that the rebound effect of CMI is 44.2%, and CMI still has large energy-conservation potentials. Based on the results of this study, some policy recommendations are provided.  相似文献   
45.
This article uses China’s input–output (I-O) tables in 2002, 2007, and 2012 to estimate the real energy consumption of each sector after the I-O adjustment. The relationship between the sectors is further analyzed using the utility analysis method based on ecological network analysis. The empirical results show that although the traditional energy-intensive industries are the major energy-consuming sectors from a direct energy consumption perspective, large energy consumption by energy-intensive industries is transferred to downstream industries through intermediate products after the I-O adjustment. Specifically, the building industry and service sector are the sectors with the highest real energy consumption. With the upgrading and optimization of the industrial structure, the proportion of energy-intensive sectors in China is declining. However, the development of the service sector and infrastructure construction still requires large intermediate inputs. Thus, industrial restructuring cannot significantly reduce China’s total energy consumption.  相似文献   
46.
PurposeThe COVID-19 pandemic has suddenly brought about a number of disruptions to when and where work is undertaken for hospitality employees. The rapid spread of COVID-19 forced many hospitality managers to use digital technologies to perform work from home, termed digital work connectivity. Yet little is known about how hospitality employees cope with it. The purpose of this study is to investigate an important yet underspecified issue as to how digital work connectivity can be detrimental for employees’ work behavior.Design/methodology/approachWe test our hypotheses using multi-wave and multi-source data collected from 467 middle managerial-level hospitality employees in China.FindingsThe findings show that digital work connectivity can lead to self-control depletion, which in turn is associated with disengagement from work. Further, the findings show that relational energy is an important resource that can buffer the detrimental effects of digital work connectivity on hospitality employees.Practical implicationsThe association of digital work connectivity with employee withdrawal behavior highlights the urgent need for hospitality enterprises to have clear guidelines that regulate technology use at home for work purposes.Social implicationsOur research shows that the absence of clear guidelines in relation to the use of digital technology for work at home risks producing unintended consequences for both hospitality employees and their enterprises.Originality/valueOur research draws from recent advances in resource allocation theories of self-control and adopts a more nuanced approach to uncover a counterintuitive reality that while people use digital technology to remain connected with work, doing so can actually contribute to their withdrawal behavior.  相似文献   
47.
在现代社会的发展中,燃煤锅炉是工业发展中常用的供暖设备、供热设备,尤其在北方地区得到了十分广泛的应用。但是,在使用燃煤锅炉过程中,一定区域内会产生很多燃煤灰尘、SO2气体,现已成为很多地区的大气污染源之一。为了有效控制燃煤锅炉污染物排放量,相关部门需要实行烟气除尘、脱硫方式,做好燃煤锅炉节能改造工作,减少大气污染物的排放量。论文重点分析了燃煤锅炉改造问题及节能环保改造措施。  相似文献   
48.
李燕 《价值工程》2014,(24):272-273
科研档案管理工作是高校事业发展的重要组成部分之一,为了改善科研档案管理中存在的归档不及时、不完整、重档轻管、只存不用等问题,可以考虑采用分级管理模式、进行信息化建设、培训档案管理人员等方法来提升高校科研档案的质量和利用率。  相似文献   
49.
Having long depended on fossil fuels for energy generation, South Africa is now investing in renewable energy. Like its mining operations, its renewable energy plants will have local implications. Renewable energy companies are therefore required by government to engage with communities to contribute to socio-economic development. We present seven lessons we believe the renewable energy sector can learn from the mining industry. We argue that the new industry must: manage social disruption, understand community complexities, create responsive institutions and the capacity to support industry practice, employ trained community practitioners, be clear about the aims of local development, encourage economic diversification in remote areas and, importantly, in view of problems caused by downscaling in the mining industry, plan for the possible closure of projects. Renewable energy projects could then serve and shape local development.  相似文献   
50.
基于长株潭城市群的调查数据,测算在燃料消耗量为5.0L/100km情景下家庭乘用车的直接能源回弹效应,并采用二分类Logistic法分析影响家庭乘用车直接能源回弹效应的因素.结果表明:长株潭城市群家庭乘用车平均直接能源回弹效应为20%;不同居民家庭乘用车的直接能源回弹效应差别较大,存在超级节能、零回弹、部分回弹和回火效应;户主受教育水平、收入水平、购买新车意愿、车辆行驶里程、出行偏好等因素对家庭乘用车超级节能和零回弹效应影响显著.  相似文献   
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