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951.
952.
pH对氢自养型反硝化菌反硝化性能的影响 总被引:4,自引:0,他引:4
采用模拟硝酸盐污染地下水(简称模拟水)驯化培养氢自养型反硝化菌,建立了定量分析氢自养型反硝化菌生物量的方法,研究了pH对氢自养型反硝化菌反硝化性能的影响。结果表明,每单位OD600相当于水样中氢自养型反硝化菌的生物量为491.75mg/L。当初始pH在6.7以下或9.2以上时,氢自养型反硝化菌生物活性会受到抑制,而初始pH为7.2、7.7、8.2和8.7时,反硝化进行12h后模拟水中的总氮去除率分别为99.7%、99.6%、96.6%和83.5%。经过12h的反硝化模拟水的pH增加0.1~0.9,硬度降低10.01~48.05mg/L;初始pH为6.7~8.7的模拟水在反硝化进行12h后生物量增加5.68~6.03mg/L,初始pH为7.7的模拟水反硝化速率最高,达0.041mg/h。 相似文献
953.
以涂有CeO2-ZrO2固溶体的堇青石蜂窝状陶瓷为载体,用浸渍法制备堇青石蜂窝陶瓷型整体La0.8Sr0.2MnO3催化剂,测试了该催化剂催化燃烧各类VOCs的特性。研究表明,VOCs催化燃烧的难易程度为:含氯烃〉烷烃〉酸〉芳烃〉酮〉酯〉醇〉醛。La0.8Sr0.2MnO3催化剂对含氧有机化合物具有较好的催化活性,完全燃烧温度均在280℃之内。通过关联VOCs的理化性质,发现VOCs在La0.8Sr0.2MnO3催化剂上的反应活性与VOCs分子中最弱C—H键键能和VOCs分子极性密切联系。 相似文献
954.
Junyu Zheng Zhuoyun Zheng Yufan Yu Liuju Zhong 《Atmospheric environment (Oxford, England : 1994)》2010,44(16):1960-1969
Using the Global Biosphere Emissions and Interactions System model (GloBEIS), 3 × 3 km gridded and hourly biogenic volatile organic compound (BVOC) emissions in the Pearl River Delta (PRD) were estimated for the year 2006. The study used newly available land cover database, observed meteorological data, and recent measurements of emission rates for tree species in China. The results show that the total BVOC emission in the PRD region in 2006 was 296 kt (2.2 × 1011 gC), of which isoprene contributes about 25% (73 kt, 6.4 × 1010 gC), monoterpenes about 34% (102 kt, 8.9 × 1010 gC), and other VOCs (OVOC) about 41% (121 kt, 6.8 × 1010 gC). BVOC emissions in the PRD region exhibit a marked seasonal pattern with the peak emission in July and the lowest emission in January, and are mainly distributed over the outlying areas of the PRD region, where the economy and land use are less developed. The uncertainties in BVOC emission estimates were quantified using Monte Carlo simulation; the results indicate high uncertainties in isoprene emission estimates, with a relative error of ?82 to +177%, ranging from 12.4 to 186.4 kt; ?41 to +58% uncertainty for monoterpenes emissions, ranging from 67.7 to 181.9 kt; and ?26 to +30% uncertainty in OVOC emissions, ranging from 88.8 to 156.2 kt on the 95% confidence intervals. The key uncertainty sources include emission factors and the model empirical coefficients α, CT1, CL, and Eopt for estimating isoprene emission, and emission factors and foliar density for estimating monoterpenes and OVOC emissions. This implies that determining these empirical coefficient values properly and conducting more field measurements of emission rates of tree species are key approaches for reducing uncertainties in BVOC emission estimates. Improving future BVOC emission inventory work in the PRD region requires giving priority to research on shrub land, coniferous forests, and irrigated cropland and pasture. 相似文献
955.
于2013年3月~2014年4月采集常州市郊区、工业区、居民区和背景点的春季、秋季大气PM_(2.5)样品,用离子色谱法分析其中水溶性离子成分,对其组成、分布特征及来源等进行研究。结果表明:SO_4~(2–)、NO_3~–和NH_4~+是常州市PM_(2.5)中的主要水溶性离子,3种离子在PM_(2.5)中占比为18%~33%。不同功能区之间水溶性离子的占比和差异较小,常州背景点可能受到周边城市污染输送的影响。在PM_(2.5)中,NH_4~+与SO_4~(2–)和NO_3~–主要以(NH_4)_2SO_4和NH_NO_3存在;硫转化率(SOR)和氮转化率(NOR)是衡量二次无机粒子转化的有效手段,常州市各功能区的SOR均大于NOR;春季SOR0.25,NOR0.1,满足发生强烈光化学氧化反应的条件。 相似文献
956.
Jafon Ng Mum Zhong Mohd Talib Latif Noorlin Mohamad Nurul Bahiyah Abd Wahid Doreena Dominick Hafizan Juahir 《Environmental Forensics》2014,15(1):8-16
A study on source apportionment of indoor dust and particulate matter (PM10) composition was conducted in a university building by using chemometrics. The objective of this study was to investigate the potential sources of selected heavy metals and ionic species in PM10 and indoor dust. PM10 samples were collected using a low-volume sampler (LVS) and indoor dust was collected using a soft brush. Inductively coupled plasma spectrometry (ICP-MS) was used to determine the concentration of heavy metals, while the concentration of cations and anions was determined by atomic absorption spectrometer (AAS) and ion chromatography (IC), respectively. The concentration of PM10 recorded in the building throughout the sampling period ranged from 20 ± 10 μgm?3 to 80 ± 33 μgm?3. The composition of heavy metals in PM10 and indoor dust were dominated by zinc (Zn), followed by lead (Pb), copper (Cu), and cadmium (Cd). Principle component analysis (PCA) and multiple linear regression (MLR) showed that the main sources of pollutants in PM10 came from indoor renovations (73.83%), vehicle emissions (16.38%), earth crust sources (9.68%), and other outdoor sources (0.11%). For indoor dust, the pollutant source was mainly earth crust. This study suggests that chemometrics can be used for forensic investigation to determine the possible sources of indoor contaminants within a public building. 相似文献
957.
制糖工业生态化重构--以贵糖集团为例 总被引:8,自引:0,他引:8
本文针对我国制糖工业存在的结构性污染、区域性污染等问题 ,按照生态工业理念 ,对广西贵港市制糖工业进行了生态化重构。介绍了贵港国家生态工业 (制糖 )示范园区的建设框架 ,并进行了物流、能流、水流和技术群分析 相似文献
958.
Yu Yao Zhuang Zhong Luo Li-yun Wang Ya-qi Li Hua-fen 《Environmental science and pollution research international》2019,26(24):24532-24541
Environmental Science and Pollution Research - Se can regulate Cd accumulation and translocation in plants; however, such effects can be controversial because of the differences in plant species... 相似文献
959.
Xu Xiangbo Ma Zhong Chen Yuqiao Gu Xiaoming Liu Qingyang Wang Yutao Sun Mingxing Chang Dunhu 《Journal of Material Cycles and Waste Management》2018,20(2):1050-1062
Journal of Material Cycles and Waste Management - The development of biogas programs in rural China has led to great economic, social, ecological and environmental benefits. The focus of this study... 相似文献
960.
Zhong Shen Wang Hongli Wen Hongmei Li Jian 《Environmental science and pollution research international》2021,28(30):40555-40567
Environmental Science and Pollution Research - As a kind of renewable resources, the effective utilization of marine resources has a significant influence on the sustainable development of economy.... 相似文献