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401.
Carbonaceous particles in the atmosphere and precipitation of the
Nam Co region, central Tibet 总被引:4,自引:1,他引:3
A continuous air and precipitation sampling for carbonaceous particles was conducted in a field observatory beside Nam Co, Central Tibetan Plateau during July of 2006 through January of 2007. Organic carbon (OC) was the dominant composition of the carbonaceous particles both in the atmosphere (1660 ng/m3) and precipitation (476 ng/g) in this area, while the average elemental carbon (BC) concentrations in the atmosphere and precipitation were only 82 ng/m3 and 8 ng/g, respectively. Very high OC/BC ratio suggested local secondary organic carbon could be a dominant contribution to OC over the Nam Co region, while BC could be mainly originated from Southern Asia, as indicated by trajectory analysis and aerosol optical depth. Comparison between the BC concentrations measured in Lhasa, those at “Nepal Climate Observatory at Pyramid (NCO-P)” site on the southern slope of the Himalayas, and Nam Co suggested BC in the Nam Co region reflected a background with weak anthropogenic disturbances and the emissions from Lhasa might have little impact on the atmospheric environment here, while the pollutants from the Indo-Gangetic Basin of Southern Asia could be transported to the Nam Co region by both the summer monsoon and the westerly. 相似文献
402.
Youzhi Li Canming Zhang Yonghong Xie Fen Liu 《Mitigation and Adaptation Strategies for Global Change》2009,14(6):537-545
Deyeuxia angustifolia is a dominant species in the Sanjiang Plain, the largest freshwater marsh wetland in China. However, this species has declined
because of great environment changes. In the effects of sea-level rise and greenhouse gas, magnitude and frequency of flood
and rate of deposit in wetland increased greatly. Thus, in this paper, effects of soil environment (soil type, burial depth,
water depth and oxygen concentration) on seed germination of D. angustifolia were investigated. Both soil type and burial depth affected seedling emergence. Seedlings emerged through 1-, 2-, 4-mm sand,
and at 1-and 2-mm mud. Regardless of soil, seedling emergence time increased and emergence percentage decreased with increasing
burial depth. For example, seedlings started to emerge on the 4th day and the final emergence percentage was 30% when covered
with1-mm mud, whereas the initial emergence time was on the 6th day and the final emergence percentage was only 8% when covered
with 2-mm mud. At the same burial depth, emergence percentage was higher in sand than in mud. Increasing water depth inhibited
seed germination. Germination percentage in 2-cm water level (20%) was 1.2 times higher than that in 12-cm water level (9%).
Oxygen concentration also affected germination. In the 21% oxygen concentration, germination was started on the 2nd day and
the germination percentage was 36%, while seed started to germinate on the 4th day and the germination percentage was only
3% at the 7% oxygen concentration. These data indicate that seed germination of D. angustifolia was highly sensitive to soil type, burial depth, water depth, oxygen concentration, and these responses may be an explicit
indication of maladjustment to environment changes, and an important reason accounting for the decline of this species in
the Sanjiang Plain. 相似文献
403.
Min-Gu Lee Dongwoo Kang Hoyong Jo Jinwon Park 《Journal of Material Cycles and Waste Management》2016,18(3):407-412
In this study, we propose a process making calcium carbonate and calcium sulfate and recovering absorbent using ammonia absorbent, carbon dioxide, and industrial waste. The main objective of this study is to confirm the possibility of carbon capture and utilization based on waste materials. We assumed desulfurization gypsum and construction waste (ready mixed concrete washing water, waste concrete, etc.) are CaSO4, Ca(OH)2, respectively. And concentration of simulated carbon dioxide gas was 15 vol% similar to flue gas. Calcium carbonate was produced by combination reaction between ionic CO2 in absorbent and metal ion in the solid waste. Experiments were conducted at normal temperature and pressure. Furthermore, the generated products were characterized by X-ray diffraction, and scanning electron microscope. 相似文献
404.
Dongjin Lee Jisu Bae Jungu Kang Kiheon Kim 《Journal of Material Cycles and Waste Management》2016,18(3):445-454
This study was to find out potential of methane yield on food waste and food waste leachate as biomass in Korea. The seven biogasification facilities were selected for comparison of theoretical methane yield and actual methane yield. The theoretical methane yield was calculated based on organic constituents (carbohydrate, protein, fat) and based on element analysis. The actual methane yield was investigated based on volatile solids and CODcr. Theoretical methane yields by organic constituents were 0.52 Sm3CH4/kg VS and 0.35 Sm3CH4/kg CODcr and these by element analysis were 0.53 Sm3CH4/kg VS and 0.36 Sm3CH4/kg CODcr. Actual methane yields were 0.36 Sm3CH4/kg VSin and 0.26 Sm3CH4/kg CODcrin. Considering the average removal efficiency of organic materials of seven FWL biogasification facilities, actual methane yields were 0.48 Sm3CH4/kg VSrem and 0.33 Sm3CH4/kg CODcrrem. Methane yield by organic constituents is very similar to that by element analysis and actual methane yields of volatile solids and CODcr were similar to theoretical value. The actual methane yield in this study showed approximated boundary values with previous other references which conducted in lab-scale or biochemical methane potential (BMP) tests. In conclusion, Korean food waste and food waste leachate have sufficient potential of methane yield in the ongoing biogasification facilities. 相似文献
405.
406.
自从国家实施西部大开发战略以来,西部地区就不断探索工业化的发展道路,在工业化的有力带动下,西部的经济发展很快。但西部地区工业化现存发展模式严重依赖能源、资源,由于对生态资源毫无节制地开发和利用,环境污染和生态破坏严重。本文通过采用典型相关分析的方法对西部工业化与生态文明建设发展模式的相关性进行分析,探寻保障我国西部能源供应、实现经济可持续发展的重要战略,试图探索实现我国西部节能规划目标的节能服务产业。用博弈论的方法分析节能服务企业的机会主义行为对节能服务产业发展的不利影响,探寻节能服务模式在我国西部发展受阻的原因,并提出了促进节能服务产业发展的对策建议。实现西部工业化和生态文明协调发展,促进西部地区经济的和谐发展。 相似文献
407.
A novel technology of two-step fast microwave-assisted pyrolysis(f MAP) of corn stover for bio-oil production was investigated in the presence of microwave absorbent(Si C) and HZSM-5catalyst. Effects of f MAP temperature and catalyst-to-biomass ratio on bio-oil yield and chemical components were examined. The results showed that this technology, employing microwave, microwave absorbent and HZSM-5 catalyst, was effective and promising for biomass fast pyrolysis. The f MAP temperature of 500°C was considered the optimum condition for maximum yield and best quality of bio-oil. Besides, the bio-oil yield decreased linearly and the chemical components in bio-oil were improved sequentially with the increase of catalyst-to-biomass ratio from 1:100 to 1:20. The elemental compositions of bio-char were also determined. Additionally, compared to one-step f MAP process, two-step f MAP could promote the bio-oil quality with a smaller catalyst-to-biomass ratio. 相似文献
408.
409.
Yanke Yu Jinxiu Wang Jinsheng Chen Xinjiang He Yujing Wang Kai Song Zongli Xie 《环境科学学报(英文版)》2016,28(9):100-108
The regeneration of commercial SCR(Selective Catalyst Reduction) catalysts deactivated by Pb and other elements was studied.The deactivated catalyst samples were prepared by chemical impregnation with mixed solution containing K_2SO_4,Na_2SO_4,CaSO_4,Pb(NO_3)_2and NH_4H_2PO_4.A novel method combining Ethylenediaminetetraacetic acid disodium salt(EDTA-2Na) and H_2SO_4solution(viz.catalysts treated by dilute EDTA-2Na and H_2SO_4 solution in sequence) was used to recover the activity of deactivated samples,and the effect was compared with single H_2SO_4,oxalic acid,acetic acid,EDTA or HNO_3 solutions.The surface structure,acidity and reducibility of samples were characterized by N_2adsorption–desorption,inductively coupled plasma optical emission spectrometer(ICP-OES),scanning electron microscopy(SEM),X-ray diffraction(XRD),X-ray fluorescence(XRF),H-2-temperature programmed section(H_2-TPR),NH3-temperature programmed desorption(NH3-TPD) and in situ DRIFTS.Impurities caused a decrease of specific surface area and surface reducibility,as well as Br?nsted acid sites,and therefore led to severe deactivation of the SCR catalyst.The use of an acid solution alone possibly eliminated the impurities on the deactivated catalyst to some extent,and also increased the specific surface area and Br?nsted acid sites and promoted the surface reducibility,thus recovered the activity partially.The combination of EDTA-2Na and H_2SO_4 could remove most of the impurities and improve the activity significantly.The removal of Pb should be an important factor for regeneration.Due to a high removal rate for Pb and other impurities,the combination of EDTA-2Na and H_2SO_4 solutions provided the best efficiency. 相似文献
410.
Estimating emissions from crop residue open burning in China based on statistics and MODIS fire products 总被引:1,自引:0,他引:1
With the objective of reducing the large uncertainties in the estimations of emissions from crop residue open burning, an improved method for establishing emission inventories of crop residue open burning at a high spatial resolution of 0.25°× 0.25° and a temporal resolution of1 month was established based on the moderate resolution imaging spectroradiometer(MODIS) Thermal Anomalies/Fire Daily Level3 Global Product(MOD/MYD14A1). Agriculture mechanization ratios and regional crop-specific grain-to-straw ratios were introduced to improve the accuracy of related activity data. Locally observed emission factors were used to calculate the primary pollutant emissions. MODIS satellite data were modified by combining them with county-level agricultural statistical data, which reduced the influence of missing fire counts caused by their small size and cloud cover. The annual emissions of CO_2, CO, CH_4,nonmethane volatile organic compounds(NMVOCs), N_2O, NO_x, NH_3, SO_2, fine particles(PM2.5),organic carbon(OC), and black carbon(BC) were 150.40, 6.70, 0.51, 0.88, 0.01, 0.13, 0.07, 0.43,1.09, 0.34, and 0.06 Tg, respectively, in 2012. Crop residue open burning emissions displayed typical seasonal and spatial variation. The highest emission regions were the Yellow-Huai River and Yangtse-Huai River areas, and the monthly emissions were highest in June(37%).Uncertainties in the emission estimates, measured as 95% confidence intervals, range from a low of within ±126% for N_2O to a high of within ± 169% for NH_3. 相似文献