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711.
The circular economy (CE) concept was introduced in China to address environmental degradation and resource scarcity associated with rapid economic development. Chosen as a demonstration city, Dalian has implemented the CE strategy as a means of conserving water, materials, energy and land. This paper outlines some of the regional CE initiatives that have been successful to date in Dalian, including those focusing on conserving energy and water resources and others focusing on reduced industrial emissions. The paper details the approach used in implementing the CE concept in Dalian, tracing the foci and goals of the program, and the sectoral approach used to implement a CE. Although Dalian municipality has achieved many successes in implementing a CE, our paper identifies several challenges that, until recently, have held back complete implementation. These include: the lack of incentives for older industries to 'green' their operations, the lack of financial support to expand the CE concept, and a broad-based need for heightened public awareness and participation in CE initiatives. Our paper then identifies several responses by Dalian municipality to overcome these challenges, including pricing and tax reforms that serve as conservation incentives, the provision of financial support for CE promotion through budget reorganization, and the organization of CE training programs. Our paper concludes that, although CE initiatives have been successful in Dalian, more is possible and more is needed before Dalian can be designated a true 'eco-city'. The approach used by Dalian can provide guidance for other Chinese cities, although it is recognized that each city must tailor its own approach for differing contexts and conditions. 相似文献
712.
Preparation and Properties of Thermoplastic Starch/Montmorillonite Nanocomposite Using N-(2-Hydroxyethyl)formamide as a New Additive 总被引:1,自引:0,他引:1
Hongguang Dai Peter R. Chang Fengying Geng Jiugao Yu Xiaofei Ma 《Journal of Polymers and the Environment》2009,17(4):225-232
N-(2-Hydroxyethyl)formamide (HF) was synthesized efficiently and used as a new additive to prepare thermoplastic starch/montmorillonite
nanocomposite (TPS/MMT). Here, HF acted as both plasticizer for TPS and swelling agent for MMT. The hydrogen bond interaction
among HF, starch and MMT was proven by Fourier-transform infrared (FT-IR) spectroscopy. By scanning electron microscope (SEM),
starch granules were completely disrupted. Atomic force microscopy demonstrated that partially exfoliated TPS/MMT nanocomposite
was formed. The crystallinity of corn starch, MMT, HF-plasticized TPS (HTPS) and TPS/MMT nanocomposite was characterized by
X-ray diffraction (XRD). Thermal stability of HTPS and TPS/MMT was determined by thermogravimetric analysis (TGA). The water
resistance of TPS/MMT nanocomposite increased compared with that of pure HTPS. Tensile strengths of TPS/MMT nanocomposites
were higher than those of HTPS, but just the reverse for elongations at break. 相似文献
713.
714.
甘肃省地震活动分布广、额度高、强度大、震源浅、震害重。全省4/5以上的面积、13个市州政府所在城市和93%的县城位于地震烈度Ⅶ度以上的高烈度区, 相似文献
715.
Hong Geng Hae-Jin Jung YooMyung Park HeeJin Hwang HyeKyeong Kim Yoo Jung Kim Young Sunwoo Chul-Un Ro 《Atmospheric environment (Oxford, England : 1994)》2009,43(21):3364-3373
Determination of the chemical compositions of atmospheric single particles in the Yellow Sea region is critical for evaluating the environmental impact caused by air pollutants emitted from mainland China and the Korean peninsula. After ambient aerosol particles were collected by the Dekati PM10 cascade impactor on July 17–23, 2007 at Tokchok Island (approximately 50 km west of the Korean coast nearby Seoul), Korea, overall 2000 particles (on stage 2 and 3 with cut-off diameters of 2.5–10 μm and 1.0–2.5 μm, respectively) in 10 samples were determined by using low-Z particle electron probe X-ray microanalysis. X-ray spectral and secondary electron image (SEI) data showed that soil-derived and sea-salt particles which had reacted or were mixed with SO2 and NOx (or their acidic products) outnumbered the primary and “genuine” ones (59.2% vs. 19.2% in the stage 2 fraction and 41.3% vs. 9.9% in the stage 3 fraction). Moreover, particles containing nitrate in the secondary soil-derived species greatly outnumbered those containing sulfate. Organic particles, mainly consisting of marine biogenic species, were more abundant in the stage 2 fraction than in the stage 3 fraction (11.6% vs. 5.1%). Their relative abundance was greater than the sum of carbon-rich, K-containing, Fe-containing, and fly ash particles, which exhibited low frequencies in all the samples. In addition, many droplets rich in C, N, O, and S were observed. They tended to be small, exhibiting a dark round shape on SEI, and generally included 8–20 at.% C, 0–12 at.% N, 60–80 at.% O, and 4–10 at.% S (sometimes with <3 at.% Mg and Na). They were attributed to be a mixture of carbonaceous matter, H2SO4, and NH4HSO4/(NH4)2SO4, mostly from the reaction of atmospheric SO2 with NH3 under high relative humidity. The analysis of the relationship between the aerosol particle compositions and 72-h backward air-mass trajectories suggests that ambient aerosols at Tokchok Island are strongly affected not only by seawater from the Yellow Sea but also by anthropogenic pollutants emitted from China and the Seoul–Incheon metropolis, resulting in the dominance of complex secondary aerosol particles. 相似文献
716.
湖北省湿地冬季水鸟多样性研究 总被引:11,自引:1,他引:11
报道了2004年1~4月湖北冬季水鸟调查结果,记录水鸟 66 种,种群数量 59 613 只,分属8目15科,其中列入国家重点保护的一级鸟类 4 种,115 只,国家二级 7 种,2 968 只。分析了冬季水鸟群落结构、分布和种群变动,并用生物多样性指数、物种丰富度与生物量3个不同的测度指标对其中12个湖泊的水鸟群落进行了评价,认为沉湖、梁子湖、龙感湖和网湖是较为成熟稳定的群落;并从沉湖东方白鹳(Ciconia boyciana)、龙感湖白头鹤(Grus monacha)、洪湖鸭科水鸟近40年的种群动态探讨了湿地水鸟现状,认为种群衰退趋势明显、湿地干扰和威胁严重。对此提出了加强湿地保护区的建设,理顺管理体制,合理规划与发展湿地产业和保护湿地资源对策。 相似文献
717.
我国水污染治理行业2007年发展综述 总被引:1,自引:0,他引:1
本文介绍了2007年我国水污染治理行业的发展概况,分析了行业发展中存在的主要问题,并提出了解决对策与建议,对行业发展前景进行了展望。 相似文献
718.
719.
洪绂曾 《中国人口.资源与环境》1992,(1)
我国是一个农业大国,具备生态农业建设的优势和特点,多年来在建设生态农业工程中,取得了经验,但还存在问题。必须提高生态农业规划目标,制定详尽的措施才能完成农业的持续稳定发展。 相似文献
720.
张德齐 《防灾减灾工程学报》1992,(4)
本文对DPJ和ULF型地震电磁辐射观测仪观测场量的主要特征进行简单的理论分析,并综合国内各地观测资料,初步探讨了电磁辐射方法在短临预报应用中有关时、空、强的前兆判据问题:1.电磁辐射异常信号的弱-强-弱-平静-发震的变化过程中,多点位异常时间趋于集中之后的信号减弱甚至平静,可能是数十小时内发震的一种标志。2.目前所观测到的地震电磁辐射信号主要来自震源(或震中)方向。3.利用lgT-M关系曲线能在一定程度上定量估算未来地震的强度。 相似文献