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91.
92.
NP型复合纳滤膜对豆腐废水处理的应用   总被引:2,自引:0,他引:2  
张伟  万慧民 《环境化学》1998,17(4):399-403
本文对NP型复合纳滤膜的分离性能进行了初步实验并在此基础上采用纳滤膜平板过滤装置对豆腐加工过程中产生的废水进行处理,以降低废水中的COD含量,实验结果表明,NP型复合纳滤膜对0.2%MgSO4溶液的截留率(R)高于90%,相应秀量约为20Lm^-2.h^-1(0.4MPa),豆腐废水COD的去除率大于90%  相似文献   
93.
为了解氮磷在不同类型水稻土发生层中的迁移特性,从浙江省宁波市和湖州市采集了27个水稻土主要发生层的原状土柱,通过饱和稳定流土柱运移试验,测定了氮和磷在不同发生层中的运移穿透曲线,用平均穿透点评估了NO-3-N、NH 4-N和PO3-4-P在各发生层中的穿透性.结果表明,氮和磷在各发生层中的穿透能力依次为:NO-3-N>NH 4-N>PO3-4-P;NO-3-N在各发生层中的穿透能力依次为:漂洗层(E层)>渗育层(P层)>表土层(A层)>腐泥层(M层)>潴育层(W层)>潜育层(G层)>犁底层(Ap层),NO-3-N的穿透能力主要与土壤饱和导水率有关,随饱和导水率增加而增强;NH 4-N穿透能力依次为:E层>P层>A层>W层>M层>Ap层>G层,NH 4-N穿透能力主要与饱和导水率和粘粒有关,迁移受粘粒明显阻滞;PO3-4-P穿透能力依次为:E层>W层>P层>M层>A层、Ap层>G层,PO3-4-P穿透能力主要受氧化铁等氧化物和粘粒的阻滞.  相似文献   
94.
Due to the increasingly serious environmental pollution and destruction,especially humans’ unreasonable activities,the ecological and economic system(EES) issues of Northwest region in China have attracted more and more attention of the researchers.Aiming at evaluating its ecological and economic system health,a multi-objective evaluation framework called PressureState-Response(PSR) was established to describe the ecological and economic health situations.Meanwhile,an integrative set pair model combining set pair analysis(SPA) and fuzzy analytic hierarchy process(FAHP) was proposed to assess the ecological and economic system.Then the EES status of five northwest provinces(Shanxi,Gansu,Qinghai,Ningxia and Xinjiang) of Northwest region in China was evaluated during 1985 to 2009.The EES development trends of five provinces are obtained.In general,the health values of five provinces showed a rising trend.The health values of five provinces grew rapidly during 1985 to 2000.After 2000,the health values of five provinces still followed the present growth trend,but the growth is relatively smooth.The results show that the method proposed is effective for assessing the health of ecological and economic system.  相似文献   
95.
China achieved major progress in low-carbon development during the period of the 11th Five Year Plan (2006-2010). The increasing trend of energy intensity and carbon intensity of the economy as seen prior to 2005 was reversed to a sharp decreasing trend, leading to a 19% decrease in energy intensity and 21% decrease in carbon intensity in five years. The enhanced energy efficiency, mostly due to efficiency improvement in power and manufacturing sector, is the major driver of the decrease in carbon intensity of the economy. The development of renewable energy, despite its impressive growth rate, played a minor role because of its small share in the energy mix of the country. Energy con-sumption and energy-related carbon emissions per unit of area in building continued to grow at a lesser rate, which, combined with the fast growth of total building volume, led to fast growth in total energy consumption and carbon emissions in the sector. Similar trend is observed in the transportation sector whose total energy use and carbon emissions continued to grow fast despite slight improvement in energy efficiency. Agricultural energy use experienced a slight change and forestry made a major contribution to carbon sinks. Policy and institutional innovations helped build a solid system of rules for low-carbon development. Improving cost effectiveness of the system remains a major challenge for the next five year plan period.  相似文献   
96.
采用自行研制的生物转鼓反应器(RDB)处理难溶于水的NO废气,为提高NO的传质系数和去除效率,实验考察了营养液中添加FeⅡ(EDTA)络合剂协同RDB以提高NO去除效率的过程。结果表明,当空床停留时间(EBRT)为0.96 min时,在营养液中添加FeⅡ(EDTA)至100 mg/L后,NO的去除效率从70.78%升至79.26%。未添加FeⅡ(EDTA)时NO去除率随营养液的增加下降,添加FeⅡ(EDTA)至100 mg/L后,去除率随营养液量的增加先上升后下降,且下降速率比上升速率大。随着营养液中FeⅡ(EDTA)浓度从0增加至500 mg/L,实验最佳温度从32.5℃升至47.5℃,但添加FeⅡ(ED-TA)至100 mg/L对实验的最适pH值没有太大影响。  相似文献   
97.
Li  Liubo  Li  Yanhui  Yang  Kai  Luan  Xinyu  Li  Meixiu  Cui  Mingfei  Sun  Yong  Wang  Huimin  Sun  Qinye  Tang  Kaili  Xu  Wenshuo  Zheng  Heng 《Journal of Polymers and the Environment》2021,29(6):1752-1762
Journal of Polymers and the Environment - In this study, novel composite aerogels of peach gum/activated carbon (PGAC) and peach gum/graphene oxide (PGGO) were synthesized by freeze-drying method...  相似文献   
98.
Sun  Hui  Zhang  Hengyuan  Mao  Huimin  Yu  Bin  Han  Jian  Bhat  Gajanan 《Environmental Chemistry Letters》2019,17(2):1091-1096
Environmental Chemistry Letters - Dyeing wastewaters present high hazards for the environment and human health. Advanced dye removal may be achieved by magnetic metal–organic frameworks...  相似文献   
99.
Zhen  Kai  Zhu  Qing  Zhai  Sheng  Gao  Yue  Cao  Huimin  Tang  Xuejiao  Wang  Cuiping  Li  Jiao  Tian  Lili  Sun  Hongwen 《Environmental science and pollution research international》2022,29(55):83234-83246
Environmental Science and Pollution Research - Once the sludge was directly used in the farmland, it will have a negative impact on human health through the food chain because sludge contains...  相似文献   
100.
We investigated the spatial distribution of Pb in soil and dust samples collected from 54 sites in Shenyang city, Liaoning province, Northeast China. Soil background Pb concentration was 22 mg kg−1 and control values from non-industrial areas were 33 mg kg−1 for soil and 38 mg kg−1 for dust. Soil Pb concentrations varied widely, ranging from 26 to 2911 mg kg−1, with a mean concentration of 200 mg kg−1, 9 times the background value and 6 times the control value. There was great variation in soil Pb, with a coefficient of variation (CV) of 1.06 and a standard deviation (SD) of 212 mg kg−1. Dust Pb concentrations fluctuated from 20 to 2810 mg kg−1, with a mean value of 220 mg kg−1, almost 6 times the control value. No significant differences in distribution were observed between soil Pb and dust Pb. The highest Pb concentration was observed in Tiexi district in an industrial area. Soil Pb concentration decreased with depth and with distance from the pollution source. Lead concentrations initially changed little but then decreased with distance from the roadside, and were generally higher on the east side of roads than on the west. Lead contents in different categories of urban area differed substantially with dust and soil Pb concentrations decreasing in the sequence: industrial >business >mixed (residential, culture and education)> reference areas.  相似文献   
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