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991.
Cheng Qian Marchetti Barbara Chen Mingfang Li Jun-Tao Wu Jiayi Liu Xiangyu Zhou Xiao-Dong 《Journal of Material Cycles and Waste Management》2023,25(3):1534-1548
Journal of Material Cycles and Waste Management - Recycling Co resource from spent lithium-ion batteries (LIBs) is significant for Co deficiency and environmental protection. A novel approach for... 相似文献
992.
剩余活性污泥和厨余垃圾续批式混合中温消化试验研究 总被引:1,自引:0,他引:1
将加碱水解和未水解剩余活性污泥与厨余垃圾混合后进行序批式中温厌氧消化,对生化产甲烷势(BMP)进行了测定.剩余活性污泥的水解通过添加NaOH进行,合理的NaOH投量为40 mmol/L,在25 ℃和35 ℃下经过6 h的水解后SCOD水解率分别提高27.4%和31.1%.厨余垃圾、25℃和35℃下水解污泥的最终甲烷产量分别为607、284、312 mL/g(VS),两种水解污泥比未水解污泥分别高出43%、57.6%,水解污泥和厨余垃圾混合消化的可降解能力要优于未水解污泥和厨余垃圾的混合进料. 相似文献
993.
Monitoring the effectiveness of management activities within reserves is always a complicated task. When the focus of management
activities is mammals, it is difficult to monitor their populations in a way that is rapid, effective, and inexpensive. We
report on a mammal survey of a reserve in southwest China using remote-trip cameras. We surveyed 329 locations over 2 field
seasons in 2002 and 2003. Sixteen species of mammals were detected with these cameras, with four species documented for the
first time. After accounting for variation due to slope, aspect, elevation, and habitat type, the distribution of six species
was positively associated with the location of conservation stations and/or patrolling routes. Species of medium-sized mammals
are excellent candidates for monitoring programs based on these cameras, due to their relative abundance, sufficient size
to be detected by the camera units, and sensitivity to human activity. The distribution of mammals relative to management
efforts is a relatively rapid means to assess reserve effectiveness. The repeat use of the cameras as part of a monitoring
plan should provide a quantifiable measure of reserve effectiveness. 相似文献
994.
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996.
黄山是我国著名的风景名胜区及世界重要的人类自然和文化遗产,具有观赏游览、科学研究及文化艺术活动等功能。为了实现旅游经济与生态环境的协调和可持续发展,提出了在黄山风景区内划分特殊自然及人文景观保护小区的观点,并划出第四纪冰川遗迹、花岗岩石林地貌、泥炭藓沼泽、松林及温泉等景观生态保护小区。主要探讨黄山风景区第四纪冰川遗迹景观生态保护小区的分布、特征及保护措施。 相似文献
997.
Yu YX Huang NB Zhang XY Li JL Yu ZQ Han SY Lu M Van de Wiele T Wu MH Sheng GY Fu JM 《Chemosphere》2011,83(2):152-160
The concentrations of PBDEs in 299 vegetable and animal-based food samples of 31 species, collected in Shanghai, China, and the bioaccessibility of PBDEs in part of the samples were determined. The PBDE concentrations ranged from 0 to 1245.4 pg g−1 with animal-based food containing more PBDEs than vegetables. The bioaccessibility of PBDEs, determined by a method simulating human gastrointestinal digestion process, were from 2.6% to 39.9% in vegetables, and from 5.2% to 105.3% in animal-based food. For animal-based food, good correlations were observed between the bioaccessibility of PBDEs and the fat content, thus the fat content in animal-based food was able to be used to estimate the bioaccessibility of PBDEs. The total daily intake of PBDEs via ingestion of vegetables and animal-based food for an average Shanghai resident was estimated as 13 235.7 and 13 668.0 pg d−1, respectively, but the amounts available for human absorption were reduced to 2674.4 and 4316.6 pg d−1 after the PBDE bioaccessibility was considered. Finally, the contributions of different food groups to the total daily intake of PBDEs were evaluated. The results revealed that, when not considering the bioaccessibility of PBDEs, vegetables were the leading contributor (49.2%), followed by fish (34.0%). However, the sequence was reversed after the PBDE bioaccessibility was taken into account. The results indicated that human exposure to PBDEs via food ingestion might have been significantly overestimated and the exposure assessment could be misleading if the bioaccessibility of PBDEs was not considered. 相似文献
998.
随着军队现代化的高速发展,严峻的资源短缺问题日益凸显,严重制约了装备的持续发展。为缓解制约装备可持续发展的资源"瓶颈",必须改变传统的粗放式发展模式,将可持续发展理念贯穿到装备全寿命周期,走资源节约型、环境友好型装备发展道路。结合我军装备建设实际情况,以实现装备可持续发展为前提,从装备科研领域、采购管理、使用管理、维修保障及退役报废5个领域入手,确定当前我军装备发展需要的新目标、新要求,借鉴国内外先进的管理理念和技术,找出适合我军特色的装备可持续发展途径,为下一步装备建设提供参考。 相似文献
999.
Recycling of printed circuit board (PCB) is an important subject and to which increasing attention is paid, both in treatment of waste as well as recovery of valuable material terms. Precede physical and mechanical method, a good liberation is the premise to further separation. In this study, two-step crushing process is employed, and standard sieve is applied to screen crushed material to different size fractions, moreover, the liberation situation and particles shape in different size are observed. Then metal of the PCB is separated by physical methods, including pneumatic separation, electrostatic separation and magnetic separation, and major metal contents are characterized by inductively coupled plasma emission spectrometry (ICP-AES). Results show that the metal and nonmetal particles of PCB are dissociated completely under the crush size 0.6mm; metal is mainly enriched in the four size fractions between 0.15 and 1.25 mm; relatively, pneumatic separation is suitable for 0.6-0.9 mm size fraction, while the electrostatic separation is suitable for three size fractions that are 0.15-0.3mm, 0.3-0.6mm and 0.9-1.25 mm. The whole process that involves crushing, electrostatic and magnetic separation has formed a closed cycle that can return material and provide salable product. 相似文献
1000.
华北平原冬小麦-夏玉米种植模式碳足迹研究 总被引:17,自引:0,他引:17
农业碳足迹理论可以系统评价农业生产过程中人为因素引起的碳排放,是构建低碳农业的理论基础,对实现低碳农业其有重要的指导意义.为探明农业生产中的碳足迹,本文基于河北吴桥县农户生产调查数据,利用农业碳足迹理论及研究方法,评价了华北平原冬小麦-夏玉米两熟种植模式的碳足迹.结果表明:冬小麦-夏玉米种植模式碳足迹的大小为1 737.37±337.02 kgCe/hm2·a,生产1 kg粮食的碳成本是0.12±0.03 kgCe,其中冬小麦的碳足迹是1 101.31±251.91 kgCe/hm2·a,小麦的碳成本是0.16±0.04kgCe/kg,夏玉米的碳足迹是636.06±163.90 kgCe/hm2·a,玉米的碳成本是0.08±0.02 kgCe/kg.冬小麦-夏玉米种植模式碳足迹的组成中,化肥占总量的61.76%,电能占25.03%,柴油占7.44%,种子占4.75%,农药占1.02%.同时,发现N肥的施用量和电能消耗量均与碳足迹有正相关性,种植规模与碳成本有负相关性.因此,构建节肥、节水及规模化的低碳种植模式是实现华北平原农业节能减排的重要途径. 相似文献