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201.
针对蓝藻资源化问题,概述国内外利用蓝藻制备有机肥、提取高纯度藻蓝蛋白、制备活性炭和藻粉这4种利用方式的特点、现状及应用进展。提出,应从高温好氧堆肥技术、藻蓝蛋白提取技术和藻水分离技术这3个方面,解决其关键技术问题并进行进一步研究开发。  相似文献   
202.
采用原子吸收光谱法(AAS法)、电感耦合等离子发射光谱法(ICP-OES法)和X-荧光光谱法(XRF法)分别测定污染土壤中的铅,并对检出限、精密度、准确度等指标进行了比对。结果表明,3种方法均能满足质量控制的要求,测定结果之间无显著性差异; 3种方法中ICP-OES法和XRF法可同时测定多元素,但XRF法更快速简便。  相似文献   
203.
Bo Söderström 《Ambio》2018,47(4):385-386
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204.
Aerobic treatment of swine manure was coupled with anaerobic digestion and microalgal cultivation. A 14-day aerobic treatment reduced the total solid content of swine manure by >15%. Ammonia and carbon dioxide were stripped by the air supplied, and this off-gas was further used to aerate the culture of Chlorella vulgaris. The microalgal growth rates in Bristol medium and the wastewater with the off-gas increased from 0.08 to 0.22 g/L/d and from 0.15 to 0.24 g/L/d, respectively. Meanwhile, the aerobically treated swine manure showed a higher methane yield during anaerobic digestion. The experimental results were used to establish a demonstration unit consisting of a 100 L composter, a 200 L anaerobic digester, a 60 L tubular photobioreactor, and a 300 L micro-open raceway pond.  相似文献   
205.
The aim of the study was to investigate the transfer of toxic metals from honeybee workers (Apis mellifera L.) to bee honey in relation to the ecological state of the environment. The materials of the study consisted of samples of honeybee bodies and varietal honeys taken from the same apiary located in three areas: R1—urbanized (16), R2—ecologically clean (16) and R3—industrialized (15) of south-eastern Poland. The contents of 14 elements in all tested samples, including toxic metals (Cd, Pb, Hg, Al, Ni, Tl) as well as bioelements (K, Mg, Ca, Mn, Fe, Zn, Cu, Se), were analysed by the ICP-OES method with prior microwave mineralization. The concentrations of the majority of the studied elements, excluding aluminum and lead, were significantly higher in bee bodies than in honey samples (P?<?0.05). The pollution of bee bodies by toxic metals was dependent on the environmental cleanliness, and the most pollution was observed in the industrialized area. The bee body was the most effective barrier for Cd and Tl transfer to the honey, while the level of Ni was similar in both tested materials. The Al concentration was significantly higher in honey than bee bodies (14.81?±?24.69 and 6.51?±?5.83 mg kg?1, respectively), which suggests the possibility of secondary contamination of honey. The greatest sensitivity to heavy metal pollution was observed in honeydew honey compared to nectar honeys (P?<?0.05). It was proved for the first time that bees work as biofilters for toxic metals and prevent honey contamination.  相似文献   
206.
In-situ measurements of atmospheric chlorofluorocarbons (CFCs) can be used to the assess their global and regional emissions and to check for compliance with phase-out schedules under Montreal protocol and its amendments. The atmospheric mixing ratios of CFC-11 (CCl3F), CFC-12 (CCl2F2) and CFC-113 (CCl2F–CClF2) have been measured by an automated in-situ GC-ECDs system at the regional Chinese Global Atmosphere Watch (GAW) station Shangdianzi (SDZ), from November 2006 to October 2009. The time series for these three principal CFCs showed large episodic events and background conditions occurred for approximately 30% (CFC-11), 52% (CFC-12) and 56% (CFC-113) of the measurements. The mean background mixing ratios for CFC-11, CFC-12 and CFC-113 were 244.8 ppt (parts per trillion, 10?12, molar) 539.6 ppt and 76.8 ppt, respectively, for 2006–2009. The enhanced CFC mixing ratios compared to AGAGE sites such as Trinidad Head (THD), US and Mace Head (MHD), Ireland suggest regional influences even during background conditions at SDZ, which is much closer to highly-populated areas. Between 2006 and 2009 background CFCs exhibited downward trends at rates of ?2.0 ppt yr?1 for CFC-11, ?2.5 ppt yr?1 for CFC-12 and ?0.7 ppt yr?1 for CFC-113. De-trended 3-year average background seasonal cycles displayed small fluctuations with peak-to-trough amplitudes of 1.0 ± 0.02 ppt (0.4%) for background CFC-11, 1.3 ± 2.1 ppt (0.3%) for CFC-12 and 0.2 ± 0.4 ppt (0.3%) for CFC-113. On the other hand, during pollution periods these CFCs showed much larger seasonal cycles of 11.2 ± 10.7 ppt (5%) for CFC-11, 7.5 ± 6.5 ppt (2%) for CFC-12 and 1.0 ± 1.2 ppt (1.2%) for CFC-113, with apparent winter minima and early summer maxima. This enhancement was attributed to prevailing wind directions from urban regions in summer and to enhanced anthropogenic sources during the warm season. In general, horizontal winds from northeast showed negative contribution to atmospheric CFCs loading, whereas South Western advection (urban sector: Beijing) had positive contributions.  相似文献   
207.
废纸苯酚液化物合成热固型酚醛树脂   总被引:2,自引:0,他引:2  
为了提高废纸的附加值,利用废纸苯酚液化物与甲醛在碱性环境中反应,进行热固型酚醛树脂合成实验。通过正交实验确定最优化的树脂化合成工艺为:n(甲醛)∶n(废纸液化物)=2.1,n(氢氧化钠)∶n(废纸液化物)=0.5,合成温度74℃,合成时间3.0h。在此工艺条件下制备的酚醛树脂压制的胶合板达到GB/T9846—2004《人造板及饰面人造板理化性能试验方法》中Ⅰ类胶合板的强度要求。  相似文献   
208.
壳聚糖三元接枝共聚物的合成及其阻垢性能   总被引:1,自引:1,他引:0  
以壳聚糖(CTS)、衣康酸(IA)和马来酸酐(MA)为原料,以醋酸为溶剂、(NH_4)_2S_2O_8为引发剂,合成了CTS-IA-MA三元接枝共聚物。聚合反应的最佳条件为:反应温度90℃,n(CTS):n(IA):n(MA)=1:1.5:1.0,引发剂质量分数0.35%,反应时间5 h。通过傅立叶变换红外光谱(FTIR)表征,所得产物为CTS-IA-MA接枝共聚物。三元接枝共聚物质量浓度为50 mg/L、水样pH为中性或弱酸性时三元接枝共聚物对CaCO_3的阻垢效果较好。  相似文献   
209.
MBR工艺处理粮油加工废水的研究   总被引:2,自引:0,他引:2  
金波  李宝新  位红卫 《四川环境》2010,29(3):24-27,31
采用MBR(Membrane Bioreactor)工艺对粮油加工废水进行处理发现,污染物的去除是活性污泥和膜截留共同作用的结果,试验中微生物的去除作用占污染物总去除率的62.9%~88.1%,起主要作用。当系统的污泥负荷和容积负荷分别在0.4~0.54 kgCOD/kgMLSS.d之间和3.8~5.0 kgCOD/m3.d之间变化时,系统对COD的去除率在92.5%以上。本试验所用膜的临界膜通量为8~10 L/(m2.h),系统污泥浓度从1~2g/L增加到10~12g/L时,临界膜通量从10~12L/(m2.h)下降到了3~4 L/(m2.h),随着膜面流速从1.0m/s上升到1.8m/s,膜的临界通量也相应的从4~6 L/(m2.h)上升到了16~18 L/(m2.h),呈正相关。  相似文献   
210.
利用JX-400过程分散控制系统(DCS),开发出300MW石灰石-石膏法脱硫控制系统,并对控制系统DCS的硬件配置、主要模拟量控制、顺序控制、辅助系统及烟气监测系统等作了简单介绍。  相似文献   
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