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501.
An integrated process of metal chelate absorption coupled with two stage bio-reduction using immobilized cultures has been proposed to continuously removal of NOx, and the effects of SO2, NO and O2 concentration, gas/liquid flow rate on NOx removal efficiency were investigated. Although nitrogen-containing components, such as Fe(II)EDTA-NO, NO2? and NO3? in the scrubbing solution, inhibited the bio-reduction of Fe(III)EDTA obviously, it was feasible to abate the inhibition effect by using the two stage bio-reduction system, and thus to improve NOx removal efficiency. The removal efficiency decreased slowly with the increase of SO2, O2, NO concentration and gas flow rate, and increased with the increase of liquid flow rate. Continuously operating for 18 days, a high removal efficiency around 95% was reached by using the two-stage bio-reduction system with immobilized microorganisms, while the value decreased to 85% after 5 days of operation by using the suspended microorganisms, at a constant gas flow rate of 60 L/h containing 424–450 mg/m3 NO, 2428–2532 mg/m3 SO2 and 3% O2. 相似文献
502.
503.
构建了高技术产业创新资源绩效评价的投入产出指标体系,利用《美国科学工程分类指标年鉴》及经济合作与发展组织(OECD) 1995-2011年高技术产业活动相关数据,运用超效率DEA模型和区域差异测度锡尔指数对全球28个国家或地区的高技术产业创新资源绩效及各区域创新资源绩效差异进行分析.结果显示:①全球28个国家或地区的高技术产业创新资源绩效水平呈现两级分化趋势.其中,新加坡、瑞士、瑞典、美国4个国家的得分较高,排名靠前,其他国家或地区绩效水平较低.②欧洲、美洲、亚洲-大洋洲之间的高技术产业创新资源绩效水平差异呈现缩小趋势,欧洲区域内部高技术产业创新资源绩效水平差异呈现逐年扩大趋势. 相似文献
504.
A new assemblage of basal dichobunoid artiodactyls from the middle-Eocene Shanghuang fissure fillings includes the diacodexeid
Jiangsudon shanghuangensis gen. and sp. nov., a new species of the lantianine dichobunoid Elaschitotherium, Elaschitotherium crepaturus sp. nov., and an indeterminate suoid which is presently the earliest record of this clade. Diacodexeids are also represented
by two forms provisionally referred to cf. Diacodexis sp. and to an indeterminate Diacodexeidae, respectively. The occurrence of diacodexeids in Shanghuang contrasts with the
early and earliest middle-Eocene chronological range of the family in Europe and North America and suggests that the stratigraphic
range of the family in Asia extends up to the middle Eocene. This may reflect particular habitats in coastal China that may
have been relatively stable during the early and middle Eocene, thus preserving forest-dwelling artiodactyls that became extinct
in the other Holarctic regions. Compared to other supposedly coeval North American, European, and Asian faunas, the Shanghuang
mammalian assemblage is most similar to early Uintan faunas of North America but is also remarkable in recording forms close
to taxa that are characteristic of the Wasatchian and Bridgerian North American Land Mammal Ages. The Irdinmanhan age of the
Shanghuang fauna is supported by the mammalian assemblage recovered from the fissure D, but an Arshantan age cannot be completely
ruled out at this point. Although the Shanghuang assemblage is biased towards preservation of small components of the mammalian
fauna, the Shanghuang fauna provide an important and unique window into the Eocene diversity and early evolution of cetartiodactyls
in eastern Asia. 相似文献
505.
Preparation of activated carbon from chicken waste is a promising way to produce a useful adsorbent for Hg removal. A three-stage activation process (drying at 200℃, pyrolysis in N2 atmosphere, followed by CO2 activation) was used for the production of activated samples. The effects of carbonization temperature (409-4500℃), activation temperature (700-900℃), and activation time (1-2.5 h) on the physicochemical properties (weight-loss and BET surface) of the prepared carbon wereinvestigated. Adsorptive removal of mercury from real flue gas onto activated carbon has been studied. The activated carbon from chicken waste has the same mercury capacity as commercial activated carbon (Darco LH) (Hg^v: 38.7% vs. 53.5%, Hg^0: 50.5% vs. 68.8%), although its surface area is around 10 times smaller, 89.5 m^2/g vs. 862 m^2/g. The low cost activated carbon can be produced from chicken waste, and the procedure is suitable. 相似文献
506.
To study the characteristics of stabilization in semi-aerobic landfill, large-scale simulated landfill was constructed based on the semiaerobic
landfill theory. Consequently, the concentrations of chemical oxygen demand (COD), ammonia nitrogen, and nitrite nitrogen,
and the pH value in leachate, as well as the component contents of landfill gas composition (methane, carbon dioxide, and oxygen) in
landfill were regularly monitored for 52 weeks. The results showed that COD and ammonia concentrations declined rapidly and did not
show the accumulating rule like anaerobic landfill, and remained at about 300 and 100 mg/L, respectively, after 48 weeks. Meanwhile,
the descending rate reached 98.9% and 96.9%, respectively. Nitrate concentration increased rapidly after 24 weeks and fluctuated
between 220–280 mg/L after 43 weeks. The pH values were below 7 during the first 8 weeks and after that leachates appeared to be
alkaline. Carbon dioxide was the main composition in landfill gas and its concentration remained at a high level through the whole
stabilization process. The average contents of carbon dioxide, oxygen, and methane varied between 19 vol.%–28 vol.%, 2 vol.%–8
vol.%, and 5 vol.%–13 vol.%, respectively. A relative equilibrium was reached after 48 weeks. The highest temperature in the landfill
chamber could amount to 75.8 degrees centigrade. 相似文献
507.
508.
本文对安徽测震台网的系统构成、子台分布、地震设备情况、传输信道、台网的技术系统功能进行了介绍。安徽测震台网部的建成,使得地震监控能力得到更大的提升,在安徽省地震应急中必将发挥积极的作用。 相似文献
509.
于2011年5~7月和10月在长江干流宜宾江段进行了鱼类资源调查。共采集到鱼类62种(亚种),隶属于4目10科40属,其中19种为长江上游特有鱼类。圆口铜鱼(Coreius guichenoti)、瓦氏黄颡鱼(Pelteobagrus vachelli)、鲫(Carassius auratus)、长薄鳅(Leptobotia elongate)、中华沙鳅(Botia superciliaris)、南方鲇(Silurus meridionalis)、铜鱼(Coreius heterodon)、鲢(Hypophthalmichthys molitrix)、鲇(Silurus asotus)等为宜宾江段优势种。对主要经济种的体长体重数据进行了分析,结果表明渔获规格较历史数据下降明显,单船日捕捞量亦有减少,长江宜宾段的渔业资源呈现衰退的趋势。作为向家坝蓄水前最后一次对宜宾江段的鱼类群落结构进行分析,研究结果可以为分析向家坝水库蓄水对长江上游鱼类的影响提供数据参考 相似文献
510.
This paper analyzes the three main fundamental issues in the design of China’s ETS pilots,including allowance allocation,price mechanism and state-owned key enterprises,and proposed suggested solutions.For the issue of allowance allocation,we suggest that the gradual hybrid mode could be applied at the beginning,which starts with mainly free allocation and then increases auction ratio gradually.And grandfathering is a suitable method of free allocation.For the issue of price mechanism,we suggest a price floating zone with open market operation to reduce the uncertainty of prices.For the issue of state-owned key enterprises,we suggest a good coordination with SASAC,defining the state-owned property right and supervision right when state-owned key enterprises are involved into the carbon market,and the local government can set rules of allocation and transaction to limit their potential market power. 相似文献