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1.
城市街区是城市肌理、空间形态、功能管理与城市健康环境建设的基本单元,应对以PM10、PM2.5为主要污染物的大气颗粒物污染,具有较高的实操性。基于城市街区影响大气颗粒物浓度与分布的要素、作用路径,以及国外城市应对大气污染的空间规划策略的经验总结,从控源、引流、集汇三方面提出基于大气颗粒物污染改善的街区空间环境优化设计方法与规划指引内容。旨在为我国普遍的城市街区提出空间形态优化策略,塑造生态健康的城市基本单元。  相似文献   
2.
The distributional effects of a major air regulation in the United State in 2015 were analyzed using Berliant and Strauss Index Numbers, a set of theoretical and empirical equity metrics, and reduced‐form models that estimate the mortality effects of air pollutant emissions and their source contributions. By viewing the effects of pollution on human mortality as an implicit tax, we found progressivity in 54% to 56% of vertical comparisons and inequity in 92% to 94% of horizontal comparisons. The introduction of the proposed policy made 58% of vertical comparisons more progressive and was equitable to 70% of horizontal comparisons.  相似文献   
3.
[目的]为了探究湖州地区太阳辐射情况,利用2009年1月至2017年12月湖州国家基本气象站的辐射观测资料、地面常规观测资料以及大气成分观测资料。[方法]文章分析了湖州地区太阳辐射的变化特征,并检验了太阳辐射与部分气象要素极值的相关性。[结果]太阳辐射日变化基本呈抛物线型。6月因湖州地区进入梅雨季节,阴雨寡照,并不是一年中辐射最大的月份,一年中辐射的最大值出现在7月,之后逐渐下降。按季节统计,夏季辐射最大,春季次之,秋季比冬季略高。除了2015年以外,近几年辐射总量平稳中稍有下降,考虑到可能存在的辐射年际变化,并不能就此认为该地区的辐射处于下降趋势中。辐射强度与总云量、低云量、最小相对湿度为负相关,与日最高温度、日最高地温呈正相关。晴天时,太阳辐射强度与颗粒物浓度PM10、PM2. 5、PM1三者相关性基本一致,均为春、秋和冬季呈负相关,夏季呈正相关,两者的关系应该按季节具体分析。[结论]影响湖州地区辐射的因子有很多,部分气象因子相关性较好,颗粒物浓度不能简单看成全年太阳辐射的影响因子。  相似文献   
4.
颗粒物空气污染是世界各国在快速城镇化过程中共同面临的严峻挑战。借助CNKI和Web of science,通过文献查阅整理城市空间在颗粒物污染方面的研究,系统性地总结该研究领域的整体特征与调节颗粒物污染的城市空间规划设计策略。结果显示:1)该研究属于一个新兴而前沿的学术领域,近年来呈持续上升趋势,相关文献主要来自中国、美国、英国与德国;2)绿色空间通过城市尺度的风道网络、绿地系统规划,街区尺度的公园绿地、湖泊湿地、道路绿带、城市森林对颗粒物污染产生消减作用;3)灰色空间通过城市尺度的城市形态优化、土地利用布局、街区尺度的街谷空间改造降低颗粒物污染;4)遥感反演与数值模拟技术(WRF、CFD)为规划设计策略提供技术支撑。最后对已有研究成果进行总结,并提出研究展望。  相似文献   
5.
于哲 《价值工程》2014,(27):228-229
本文通过对于Beta射线技术的分析得到一种可以用于环境空气颗粒物PM2.5连续监测过程的技术,并对该技术在不同条件下进行测试,通过所得到的数据得出该技术的适用性和技术局限性。  相似文献   
6.
在模拟发动机排气条件下对等离子体与催化剂协同脱除柴油机NOx进行了测试。考察了单独等离子体、单独催化、等离子体与催化协同作用下的转化效果,分别测试了NO体积分数、还原HC体积分数、输入能量密度、催化载体类型、温度以及CO,H2,CO2等因素对NOx转化效率的影响。  相似文献   
7.
The objective of this case study was to assess economic benefits of past environmental policies of particulate matter (PM) in Tokyo by comparing observed pre‐control PM levels in 1975 and post‐control levels in 1998. The point estimates of the numbers of additional cases of avoided premature mortality and morbidity due to PM pollution control were (1) 3900 long‐term deaths in adults aged 30 years and older (population 5?098?000), (2) 4700 cases of chronic bronchitis in adults aged 30 years and older, (3) 7800 cases of in‐patient cardiovascular disease in adults aged 65 and older (population 1?281?942), (4) 3100 cases of in‐patient pneumonia in adults aged 65 and older, (5) 2500 cases of in‐patient chronic obstructive pulmonary disease in adults aged 65 and older, (6) 390?000 asthma attacks in asthmatics (population 450?000), and (7) 4500 cases of acute bronchitis in children aged 8–12 (population 300?300) during a one‐year period. The point estimate of medical costs in adults and children plus the cost of lost wages was a purchasing power parity‐adjusted $38 billion USD. Overall these results appear more likely to be underestimates than overestimates due to several unquantified benefits. The calculations of avoided health and productivity impacts suggest that pollution control policies successfully prevented a large expense to the society in extra medical care and lost work time.  相似文献   
8.
The objectives of this study were to assess avoided economic costs (or anticipated ‘benefits’) of not implementing new environmental policies for particulate matter (PM) in Japan and compare these future benefits to estimates of future health risks developed in a separate analysis. The estimates for the benefits of avoided PM pollution control in the year 2010 were (1) $27 billion USD for stationary source controls, (2) $2.1 billion to $3.3 billion USD for diesel motor vehicle controls, (3) $41 million USD for governmental employee salaries, (4) $470 million USD for governmental financial assistance, (5) $510 million USD for special diesel vehicle control measures in Tokyo, and (6) $31 billion USD for total costs.

Using human health and productivity risks, calculated in a separate study to be $56 billion USD, the best net ratio of benefits to costs was 1.8 to 1. Inexpensive control options include road watering or paving for unpaved dirt roads and road vacuuming for paved roads. Intermediate options include differential road pricing, retrofitting diesel particulate filters, and reformulating diesel fuel. High cost options include adding particulate controls, such as wet scrubbers, baghouses, and electrostatic precipitators on uncontrolled stationary sources.  相似文献   
9.
赵晓靖 《价值工程》2014,(25):320-321
近年来研究表明,颗粒物已成为环境空气污染最突出的问题之一。由于颗粒物的污染,华北地区主城区环境空气质量超标的日数也为数不少。此外,由于颗粒物能够散射太阳光,对大气能见度和气候造成一定的影响,给交通和生活也带来极大的不便。那么由此,研究颗粒物的组成并更好地控制它们是很有必要的。  相似文献   
10.
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