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Scientific research training is an essential part of undergraduate learning, which plays an important role in improving students' knowledge utilization and scientific literacy. Taking the participation process of "Energy conservation and emission reduction competition" as an example, this paper briefly introduces the undergraduate scientific research training of students majoring in polymer materials and engineering from their own perspective, and the way to combine the discipline and school characteristics to reflect the thinking of engineering students in scientific research and practical application. 相似文献
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节能服务企业效率对于推动节能服务产业发展和确保国家“双碳”目标实现具有重要意义。运用三阶段SBM模型,对2020年60家中国节能服务上市企业的综合效率进行实证研究,并分析效率的影响因素。研究结果表明,经济发展水平对综合效率具有双重影响,合适的产业结构和较高的投入资本回报率有利于综合效率提升,而政府补贴与企业存续时间制约了综合效率改进;剔除环境因素与随机误差影响后,多数企业综合效率下降,整体效率偏低;提高规模效率是提升综合效率的关键,且绝大部分企业处于规模收益递增状态。研究最后提出创新补贴方式、建立企业认证制度、开展综合能源服务和推动企业间兼并重组等可行建议,以提升节能服务企业的综合效率。 相似文献
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Establishing a reliable method to predict the global mean temperature (Te) is of great importance because CO2 reduction activities require political and global cooperation and significant financial resources. The current climate models all seem to predict that the earth's temperature will continue to increase, mainly based on the assumption that CO2 emissions cannot be lowered significantly in the foreseeable future. Given the earth's multifactor climate system, attributing atmospheric CO2 as the only cause for the observed temperature anomaly is most likely an oversimplification; the presence of water (H2O) in the atmosphere should at least be considered. As such, Te is determined by atmospheric water content controlled by solar activity, along with anthropogenic CO2 activities. It is possible that the anthropogenic CO2 activities can be reduced in the future. Based on temperature measurements and thermodynamic data, a new model for predicting Te has been developed. Using this model, past, current, and future CO2 and H2O data can be analyzed and the associated Te calculated. This new, esoteric approach is more accurate than various other models, but has not been reported in the open literature. According to this model, by 2050, Te may increase to 15.5 ℃ under "business-as-usual" emissions. By applying a reasonable green technology activity scenario, Te may be reduced to approximately 14.2 ℃. To achieve CO2 reductions, the scenario described herein predicts a CO2 reduction potential of 513 gigatons in 30 years. This proposed scenario includes various CO2 reduction activities, carbon capturing technology, mineralization, and bio-char production; the most important CO2 reductions by 2050 are expected to be achieved mainly in the electricity, agriculture, and transportation sectors. Other more aggressive and plausible drawdown scenarios have been analyzed as well, yielding CO2 reduction potentials of 1051 and 1747 gigatons, respectively, in 30 years, but they may reduce global food production. It is emphasized that the causes and predictions of the global warming trend should be regarded as open scientific questions because several details concerning the physical processes associated with global warming remain uncertain. For example, the role of solar activities coupled with Milankovitch cycles are not yet fully understood. In addition, other factors, such as ocean CO2 uptake and volcanic activity, may not be negligible. 相似文献
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《数学的实践与认识》2015,(11)
金融危机的爆发宣告过去那种褐色、高碳增长、缺乏监管、放任自由的发展模式的结束.发展绿色新兴产业、实现绿色复苏、向绿色经济与低碳经济转型成为越来越多国家解决多重挑战的共识和争取双赢的选择.一场抢占发展制高点,围绕绿色发展的竞争已在全球展开.通过对江西省产业结构演变及产业内部结构进行分析,总结出江西省绿色转型所面临的问题,如重化工业占主导地位,产业技术落后,资源环境效率低和缺乏必要的政策措施等.利用环境学习曲线对江西省工业节能减排潜力进行分析,并对江西省单位产品能耗与全国平均水平和国际水平进行比较,发现江西省技术水平和发达地区还有很大差距,工业节能减排潜力巨大.在此基础上,最后提出了促进江西省产业绿色转型的政策建议. 相似文献
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本文提出一种新颖的甲醇化学链燃烧动力循环系统.该系统利用空气压缩的间冷热提供甲醇和Fe2O3反应热,将间冷的低温热转换为高品位化学能;同时得到预冷的空气吸收燃烧产物Fe2O3的显热,降低了还原反应的温度.与常规化学链循环相比,该循环利用间冷的热量代替高温Fe2O3的显热提供还原反应的反应热,系统内能量品位匹配更加合理.根据图像(火用)分析方法,阐明了甲醇化学链燃烧过程(火用)损失减少和间冷热品位提升的机理.本文对新循环进行了分析,并以常规化学链循环为参照,研究了其性能.新循环的效率较高,同时可以实现CO2无能耗的分离. 相似文献