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181.
李辉  庞博  朱法华  孙雪丽  徐静馨  王圣 《环境科学》2022,43(11):5294-5304
选取2020年世界能源消费量累积占比达80%的前23个国家作为研究对象,通过从一次能源清洁化率、化石能源清洁利用率和电能占终端能源消费率角度对其能源消费结构进行对比研究,从单位GDP能耗、人均能耗和单位国土面积能耗角度,结合产业结构和分部门能源消费构成,对其能源消费强度进行深入分析,探讨各国在社会经济运行与生产生活中的能源消费模式,提出能源消费自然碳汇承载负荷比概念,指出我国在碳达峰与碳中和目标下能源消费模式转型面临的优势与挑战.结果表明,我国一次能源清洁化率、发电用能占比、化石能源清洁化利用率和电能占终端能耗比分别达到15.90%、53.48%、37.51%和26.54%,均在世界主要能源消费国家中处于前列,已经架构起良好的能源集约化和清洁化利用结构基础;非工农业能源消费占比尤其是仅为14.09%的交通能源占比在主要能源消费国中最低,已经形成了具有相对优势的绿色低碳能源消费模式;基于产业结构优化潜在的总体能源生产率还有较大提升空间;但相对较短的碳达峰与碳中和目标期对清洁能源发展速度与规模提出了巨大挑战,碳排放约束下的国际形势对我国通过优化调整产业结构实现降碳目标也增加了难度.  相似文献   
182.
城市生态休闲绿地不同于城市绿地,主要包括其中的城市公园绿地和其他绿地。结合市民平时主要在居住地附近散步、节假日喜欢到郊区游憩的休闲活动特点,把生态休闲绿地分为日常短时休闲绿地和节假日长时休闲绿地。在城市生态休闲绿地建设中,应重点建设日常短时休闲绿地,配套开发节假日长时休闲绿地,完善城市公共绿地的休闲设施,增强城市公共绿地的大众性,提高专有绿地的开放性。  相似文献   
183.
This paper addresses claims that the value-added wood industries contribute towards an economically and environmentally sustainable forest economy in British Columbia, Canada. The small firms that comprise the value-added industries have grown in number, are relatively labour intensive, draw upon diverse, small volume timber supplies, and serve a wide variety of niche markets. Conceptually, the study is informed by an integration of the flexible specialisation model with green entrepreneurship. Empirically, the study adopts an extended case study approach and is based on in-depth semi-structured interviews with respondents of 41 small firms that represent various value-added wood processing activities in Metro Vancouver and with industry associations. The study found that these firms are modestly flexibly specialised and locally embedded but inter-firm networking is weak. As green entrepreneurs, they reveal variation in environmental awareness and performance but are adopters rather than leaders.  相似文献   
184.
Decision-making in spatial planning is often based only on administrative regulations and procedures. This approach does not guarantee an efficient allocation of scarce financial resources. Consequently, the present paper discusses the practical relevance of an approach to incorporate results of economic valuation into strategic spatial planning for the example of green infrastructure. For this, a contingent valuation was conducted at a reference site in Esslingen, Germany. Here, participants of the survey stated their willingness to pay for different green infrastructure investment categories. Build on the survey results, the possible future foci of regional green infrastructure planning are derived and impacts on regional green infrastructure policy for the case of the Neckar region are investigated.  相似文献   
185.
Few studies exist on how chloride from chloride‐based deicers is transported in infiltration‐based stormwater control measures. In 2009, the U.S. Environmental Protection Agency (USEPA) constructed a 0.4 ha parking lot in Edison, New Jersey, that was surfaced with permeable interlocking concrete pavers (PICP), pervious concrete (PC), and porous asphalt (PA). Each surface type has four equally sized, lined sections that direct all infiltrate to separate 5.7 m3 collection tanks. The USEPA acute criterion for aquatic life (860 mg/l) was exceeded in events immediately following a snow event. Concentrations of the infiltrate exceeded the detection limit (5 mg/l) year round but did not exceed the USEPA chronic toxicity (230 mg/l) after April. The chloride concentration decreased with cumulative rainfall since previous snow event, and a power regression described this relationship. In the power regression, the coefficient (b) described the initial concentration following a snow event, and the exponent (m) described the rate in which chloride was flushed through the system with infiltrating water. PC had the largest coefficient (5,664) and largest absolute exponent (?0.92), followed closely by PICP (= 4,943 and = ?0.87), and distantly by PA (= 2,907 and = ?0.67). The differences in release rate were proportional to the measured surface infiltration rates of 4,000; 2,400; and 200 cm/h for PC, PICP, and PA, respectively. These results will assist those who manage or regulate stormwater where receiving waters are chloride impaired.  相似文献   
186.
The formulation and scale-up of batch processes is one of the major challenges in the development of pharmaceutical dosage forms and at the same time a significant resource demanding process which is generally overlooked in environmental sustainability assessments. First, this paper proposes general trends in the experience curve of cumulative resource consumption of pharmaceutical tablet manufacturing of PREZISTA® 800 mg through wet granulation (WG) at four consecutive scales in both R&D and manufacturing environments (resp. WG1 = 1 kg/h, WG5 = 5 kg/h, WG30 = 30 kg/h and WG240 = 240 kg/h). Second, the authors aim at evaluating the environmental impact from a life cycle perspective of a daily consumption of PREZISTA® 2× 400 mg tablets versus the bioequivalent PREZISTA® 800 mg tablet which was launched to enhance patient compliance. Environmental sustainability assessment was conducted at three different system boundaries, which enables identification, localization and eventually reduction of burdens, in this case natural resource extraction. Exergy Analysis (EA) was used at process level (α) and plant level (β) while a cradle-to-gate Exergetic Life Cycle Assessment (ELCA) was conducted at the overall industrial level (γ) by means of the CEENE method (Cumulative Exergy Extraction from the Natural Environment). Life cycle stages taken into account are Active Pharmaceutical Ingredient (API) production, Drug Product (DP) production and Packaging. At process level (α), the total resource extraction for the manufacturing of one daily dose of PREZISTA® (800 mg tablet) amounted up to 0.44 MJex at the smallest scale (WG1) while this amount proved to be reduced by 58%, 79% and 83% at WG5, WG30 and WG240 respectively. Expanding the boundaries to the overall industrial level (γ) reveals that the main resource demand is at the production of the Active Pharmaceutical Ingredient (API), excipients, packaging materials and cleaning media used in DP production. At the largest scale (WG240) the use of cleaning media during DP production contributes considerably less to the total resource extraction. Overall, the effect of scale-up and learning on resource consumption during DP production showed to possess a power-law experience curve y = 2.40 * x−0.57 when shifting from WG1 (smallest lab scale) to WG240 (industrial manufacturing). Tablet dosage (2× 400 mg versus 1× 800 mg) did not significantly affect the absolute environmental burden. However, the relative contribution of resource categories did change due to the different production technology. It could be concluded that in meeting social and economic demands by launching the PREZISTA® 800 mg tablet, no trade-off in environmental burden occurred. On the long term, future research should strive to take into account R&D processes and all services related to pipeline activities taking place prior to market launch and eventually to allocate impacts to the final product.  相似文献   
187.
论绿色经济网络   总被引:1,自引:0,他引:1  
绿色经济的发展过程是对传统经济的扬弃过程,在这一过程形成了各种形式的绿色经济系统,这些系统组成了一个绿色经济网络。绿色经济网络本身也在不断演进,范围逐步扩大,绿色内涵逐步深化。本文论述了绿色经济网络的形成与演进过程,并构建了绿色经济系统演进的推进模型。  相似文献   
188.
绿色GDP理论基础与核算思路探讨   总被引:13,自引:0,他引:13  
在可持续发展理论的冲击下,绿色GDP核算受到了学术界的广泛关注。本文讨论了绿色GDP植算的概念、意义及相关理论基础,并且进一步提出,绿色GDP核算在方法上存在直接测算与间接测算两种思路。理论上进两种思路各有利弊,但从实践上看,这两种核算方法都迁存在不少的难点。  相似文献   
189.
废弃电路板湿法破碎能耗试验研究   总被引:1,自引:1,他引:0  
采用Design-Expert 7.1软件对废弃电路板湿法冲击式破碎机能耗试验进行了方案设计和结果分析;拟合出了能耗与试验影响因素之间的定量关系模型,给出了能耗的残差分布以及不同操作变量之间的等高线和三维响应关系;利用Design-Expert 7.1对电路板破碎能耗试验的条件进行了优化,获得了最佳的操作指标。  相似文献   
190.
蔡博峰  曹东  刘兰翠  张战胜 《环境工程》2012,30(1):124-127,131
基于全国涉及石灰生产的企业全口径统计数据,分析中国2007年石灰生产的基本特征,探讨了石灰产量统计的不确定性和来源。2007年,中国石灰生产的企业共6 154家,涉及9 327座石灰窑。总产能为2.27亿t,共生产石灰1.06亿t,企业平均产量为4 000 t/a,企业生产每吨石灰平均能耗水平为163 kg标准煤。中国约有两千八百多万吨的石灰生产很难通过正规渠道统计上来,也意味着这些产量很可能是基于非常简易和高能耗的石灰土窑生产的。  相似文献   
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