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1.
 采用生物膜填料塔净化SO2废气,研究结果表明:其最佳操作条件为入口气体质量浓度500~1 000mg/m3、气体流量100 L/h、循环液流量15 L/h,pH 1.0;当气体流量从100 L/h增加到300 L/h时,SO2净化效率由86.4%下降到73.2%;最佳操作条件下SO2净化效率可达98%以上.  相似文献   

2.
制备了铁酸钴-氧化铝(CoFe2O4-Al2O3)复合材料,并采用扫描电子显微镜(SEM)、X射线衍射(XRD)、比表面积和孔径分析仪对多孔CoFe2O4-Al2O3复合材料的物相和形貌进行了分析. 利用制备的CoFe2O4-Al2O3复合材料活化过硫酸氢钾(PMS)来降解废水溶液中的日落黄(SY),通过研究CoFe2O4-Al2O3材料制备过程中Co2+,Fe3+和Al3+的物质的量之比、煅烧温度和时长对材料催化性能的影响,发现Co2+,Fe3+和Al3+的最佳物质的量之比为1:2:12,最佳煅烧温度为400 ℃和最佳煅烧时长为3 h. 对采用在最优条件下制得的CoFe2O4-Al2O3复合材料作为催化剂,PMS氧化降解含日落黄废水进行研究,考察了pH值、温度、不同体系、PMS用量、CoFe2O4-Al2O3材料用量和一些阴离子对日落黄降解的影响. 结果表明:在pH=7,温度为55 ℃条件下,用0.1 g催化剂和0.125 g PMS能使100 mL质量浓度为0.6 g·L-1的日落黄溶液在30 min内降解率达到99.5%. 同时,碳酸氢根负离子(HCO3-)和硝酸根负离子(NO3-)的加入抑制了日落黄的降解,而Cl-则能促进日落黄的降解. 此外,在进行4次循环使用后,CoFe2O4-Al2O3仍表现出很好的催化性能,日落黄去除效果仍能达到90%以上.  相似文献   

3.
NiCo2O4是一种很前景的甲苯氧化催化剂。本文以Ce为杂原子,利用水热法制备Ce/NiCo2O4催化剂,以提高NiCo2O4尖晶石表面活性氧生成速率。采用氢气程序升温还原(H2-TPR)、X射线光电子能谱(XPS)、X射线衍射(XRD)、比表面积测定(BET)、以及透射电子显微镜(TEM)等表征催化剂。通过改变铈掺杂量,得到最佳掺杂比例。甲苯降解实验表明,在甲苯浓度为2538ppm,空速为10000h-1,催化剂体积为0.5mL 时,一次水热法制备得到的15%Ce/NiCo2O4催化剂降解性能最优(T99=267℃),在267℃下进行催化反应72h后催化剂性能无显著变化。机理研究发现,掺杂铈可提升催化剂中高价金属含量,同时催化剂良好的氧化还原性能可加快表面活性氧生成速率,从而催化性能得以提升。  相似文献   

4.
北京气象塔秋季大气O3,NOx及CO浓度变化的观测实验   总被引:9,自引:0,他引:9  
利用北京325m气象塔作为高空平台,于1998年秋季进行了大气污染物臭氧(O3)及其前体物氮氧化物(NOx)、一氧化碳(CO)和气象要素的同步观测.分析边界层内O3,NOx,CO浓度(用体积分数表示)的变化规律,发现边界层内存在明显的O3体积分数的垂直差异,低层(47m)O3体积分数存在典型的日变化,夜间高层(280m)O3的化学消耗较弱,可维持较高的体积分数,并受水平平流等气象因子的影响.局地光化学生成是白天大气边界层O3的主要来源.冷锋天气过程可造成O3及其前体物体积分数的显著变化.  相似文献   

5.
针对太湖原水中氨基酸氯化消毒后可能引发的嗅味问题,采用太湖某水厂滤后水为研究对象,考察了O3/H2O2深度处理工艺对水中致嗅氨基酸的去除效果及影响因素。结果表明滤后水中致嗅氨基酸占总游离氨基酸的81.6%,采用O3/H2O2工艺降解致嗅氨基酸的最佳投量为1.5 mg·L-1 O3和0.06 mM H2O2,去除率91.28%,致嗅氨基酸浓度降至484.62 ng·L-1,加氯消毒后几乎没有致嗅风险。水温10~30℃范围内,O3/H2O2对致嗅氨基酸的去除率随温度升高而增大;pH=6~8范围内,去除率随pH的升高而增大。另外,该组合工艺较单独O3/H2O2对溴酸盐的生成也有明显抑制作用。  相似文献   

6.
采用杂化密度泛函理论(DFT)的B3LYP方法,在6-311++G (d, p)基组水平上对Li3O 0, +超碱团簇的几何结构和稳定性进行理论计算,并研究了Li3O+团簇的储氢性能。结果表明,Li3O+团簇结构相比中性Li3O团簇结构的动力学稳定性要高。氢分子在Li3O+团簇表面能以介于物理吸附与化学吸附之间的形式吸附,每个Li原子最多可以有效吸附三个H2,储氢质量分数可达33.01 wt%。H2分子在Li3O+团簇表面的平均吸附能范围为1.959~3.591 kCal/mol,该吸附能满足在近室温条件下可逆吸放氢反应的热力学要求。  相似文献   

7.
采用亚铁(Fe2+)分别联合次氯酸钠(NaClO)、过硫酸钠(Na?S?O8)和过氧化氢(H2O2) 3种氧化剂处理某原油浸染土壤的热脱附废水,考察了pH值、Fe2+投加量、氧化剂投加量和反应时间对处理效能的影响。Fe2+/H2O2和Fe2+/ Na?S?O8均能有效去除热脱附废水中的典型污染物——石油烃物质,去除率分别达到100.0%和97.8%,但Fe2+/H2O2体系对化学耗氧量(COD)的去除效果明显优于Fe2+/Na?S?O8。Fe2+/H2O2可将有机物彻底氧化分解,而Fe2+/NaClO和Fe2+/Na?S?O8仅是将有机物氧化分解为中间物质。多元变量分析结果表明,pH值和氧化剂投加量是影响去除效果的主要因素,Fe2+/H2O2处理热脱附废水的吨水处理成本较高,但是综合效果最好;Fe2+/Na?S?O8处理成本次之,但无法彻底降解COD;Fe2+/NaClO成本最低,但对有机物去除效果最差。综合去除效果和经济因素考量, Fe2+/H2O2体系更适用于处理热脱附废水。  相似文献   

8.
以初始镍质量浓度为50 mg/L的柠檬酸镍废水为研究对象,第一段采用芬顿法进行破络,第二段采用“O3/Fe2+”臭氧组合工艺进一步处理。探讨了芬顿段H2O2投加量和臭氧组合工艺中pH、臭氧投加量、Fe2+投加量、干扰离子对于镍离子去除效果的影响。实验结果表明,芬顿段最佳条件:H2O2投加量为0.15 mL/L,初始pH为5.0,Fe2+投加量为111.11 mg/L,反应时间为12 min;臭氧组合工艺段最佳条件:维持O3质量浓度为30 mg/L,反应时间为18 min,在两段工艺的最佳条件下,柠檬酸镍废水中约99.8%的柠檬酸镍得以去除,出水镍浓度达到国家排放标准。  相似文献   

9.
液相催化氧化净化烟气中SO2和NOx的实验研究   总被引:3,自引:0,他引:3  
 采用Fe2+,Mn2+,Zn2+,Al3+4种金属离子进行了催化氧化SO2和NO废气的实验.对循环吸收液的酸度、催化剂浓度最佳配比及操作条件的改变等对SO2和NO催化氧化效率的影响及其变化规律进行了研究.结果表明,当Fe2+,Mn2+,Zn2+,Al3+质量分数分别为0.5%,0.2%,0.5%,1.0%,气体流量为0.1 m3/h;循环液流量为6~8 L/h时,SO2和NO催化氧化效率分别为95%和50%以上.  相似文献   

10.
利用低温下的水化学生长法合成了镍钴氧化物(NiCo2O4)纳米针,因其自组装而表现出立方晶相,再用二氧化钛/炭黑(TiO2/CB)对NiCo2O4表面进行了改性,合成了TiO2/CB-NiCo2O4复合纳米材料.用X射线光电子能谱仪(XPS)、扫描电子显微镜(SEM)、能量色散X射线光谱仪(EDX)图谱对材料的形貌进行了表征,运用循环伏安法(CV)、时间-电流(i-t)曲线法考察了TiO2/CB-NiCo2O4修饰玻碳电极的电化学行为.实验发现:TiO2/CB-NiCo2O4修饰电极对葡萄糖的氧化有良好的电催化性能,其线性范围为0.001~1.780 mmol·L-1,检测限为0.53 μmol·L-1(信噪比S/N=3).将该法用于实际样品中葡萄糖的测定,结果令人满意.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

16.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

17.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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