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1.
微生物固定法降解含聚废水的最佳条件   总被引:2,自引:0,他引:2  
利用从含聚废水中分离纯化得到的单一菌株R4-1,R4-2,R4-3,R4-5,H4-3,以海藻酸钠-PVA为包埋剂,采用包埋固定法对5种菌的混合菌进行固定化实验.通过单因素实验和正交实验,系统考察了湿菌体与包埋剂的体积比、氯化钙质量分数、硼酸质量分数和交联时间等因素对聚丙烯酰胺降解率的影响.实验得到微生物固定法降解含聚废水的最佳制备条件:4%海藻酸钠,4%的PVA,湿菌体与包埋剂体积比1∶1,2%氯化钙,3%硼酸,分段交联时间为氯化钙4h后硼酸20h.湿菌体与包埋剂的体积比对聚丙烯酰胺降解率的影响十分显著.追加实验最佳制备条件,得到微生物固定化颗粒对含聚废水的降解率可达到83.1%.  相似文献   

2.
从河流底泥、河水水体中分离得到一株黄杆菌Flavobacteriumsp.(Oil56).用聚乙烯醇(polyvinylalcohol,PVA)和海藻酸钠(sodiumalginates,Na·Alg)为包埋载体,以五硼酸铵和氯酸铁溶液为交联剂,固定黄杆菌Flavobacteriumsp.Oil56得到固定化球形颗粒.对比研究了固定化颗粒与游离菌对地表水的降解效果,结果表明在COD初始质量浓度为77~205mg/L时,用固定化Flavobacteriumsp.Oil56修复48h的COD去除率为48.2%~50.6%,比游离菌的降解效率提高了42.7%~45.8%.利用扫描电镜(SEM)研究了固定化球形颗粒在降解过程中的微环境变化.  相似文献   

3.
从印染厂采集的活性污泥中筛选得到1株快速降解甲醛的菌株并命名为 W1,通过形态与生理生化特征的鉴定,初步鉴定 W1菌株为假单胞菌属(Pseudomonas).以海藻酸钠为包埋载体固定 W1菌株进行降解甲醛的初步研究,采用不同海藻酸钠浓度、菌悬液添加量配制成不同的包埋载体,利用 L9(33)正交试验对 W1菌株降解甲醛条件进行优化,分析其甲醛降解率的变化.实验结果表明:培养基为(NH4)2 SO42.4 g/L, MgSO4?7H2 O 0.2 g/L,微量元素母液0.1 mL,pH 值9.0,30℃恒温培养,在此条件下甲醛48h内的降解率达80.3%.通过对甲醛降解菌 W1固定化的研究,为生物法去除甲醛的应用奠定基础.  相似文献   

4.
为了提高固定化啤酒酵母絮凝岩溶水硬度和矿化度的能力,采用固定化剂海藻酸钠包埋啤酒酵母,并制备了粒径1~2mm的固定化啤酒酵母絮凝剂小球。以啤酒酵母固定化菌的物理性质及对岩溶水硬度和矿化度絮凝率为指标,考察了固定化因素海藻酸钠质量分数、菌体海藻酸钠质量比、交联时间及氯化钙质量分数对固定化小球的物理性质及絮凝岩溶水的影响。结果显示,制作固定化菌的最优固定化条件分别为:海藻酸钠质量分数2.0%-3.0%、菌体海藻酸钠质量比6%-8%、交联时间6~10h和氯化钙质量分数2.0%-4.0%,此时的啤酒酵母固定化菌物理性质最优。由正交实验确定影响因素主次顺序及最优水平组合后,结果发现:较其他因素而言,海藻酸钠质量分数与菌体包埋比对絮凝率影响较大;当选取质量分数为2.0%的海藻酸钠、10%的菌体质量比、4.0%的氯化钙和10h的交联时间条件下制作的固定化小球,在投加量4g·L-1,絮凝时间60min时,对岩溶水的矿化度和硬度絮凝率分别达到76.97%和59.77%,处理后的岩溶水矿化度从3 109mg·L-1降到1 258mg·L-1,矿化度达到了《地下水质量标准》(GB/T14848-93)的Ⅳ类用水标准,硬度从2 856mg·L-1降到了658mg·L-1,硬度接近《地下水质量标准》(GB/T14848-93)的Ⅳ类用水标准。  相似文献   

5.
选用海藻酸钠(CA)和聚乙烯醇(PVA)混合物作为包埋载体,对经富集培养的以反硝化聚磷菌为主的活性污泥固定化制备方法进行了研究.利用正交实验考察了包埋菌体量、海藻酸钠质量分数、沸石添加量和交联时间对固定化菌除磷效果的影响,着重研究了包埋菌体量和沸石添加量这2个显著性影响因素对固定化小球性能的影响.研究表明,制备固定化反硝化聚磷菌的最佳包埋条件是:PVA质量分数为8%,CA质量分数为3%,包埋菌质量体积浓度为25g/L,沸石质量体积浓度为20 g/L,固定化小球交联时间为18 h.  相似文献   

6.
以海藻酸钠为包埋载体,活性炭为添加材料,对沼泽红假单胞菌Rhodopseudomonas palustris PSB-1D进行固定化,通过正交试验确定固定化微生物小球的最佳制备条件:活性炭添加量为1%,海藻酸钠质量分数为3%,包埋菌体与包埋材料的质量比为1/20。在最佳条件下,微生物小球培养7 d后对2-氯苯酚(2-CP)的降解率为72.6%。对比研究微生物小球和游离细菌的降酚效果。将微生物小球引入序批式好氧生物反应器(SBR)工艺中,分别研究小球投加量、曝气时间、曝气量对生物反应器降解2-氯苯酚效果的影响。试验结果表明:微生物小球对2-CP的降解率较游离细菌有明显提高。在黑暗好氧条件下,有效容积为5 L的固定化生物反应器对2-CP模拟废水降解处理的最佳稳定工艺条件为:微生物小球投加量为20 g,曝气时间10 h,曝气量为100 L/h。在此条件下,经过连续30个周期的测定,微生物小球对2-CP的平均去除率始终保持在65%左右。  相似文献   

7.
从某焦化厂处理废水的活性污泥中筛选到一株苯酚高效降解菌(Wust-C),该菌属革兰氏阴性菌.对Wust-C降解苯酚的特性进行试验研究.结果表明,在初始苯酚浓度为1 000 mg/L的试样中,培养24 h后,Wust-C对苯酚的降解率可达98%;初始苯酚浓度为300 mg/L试样中的苯酚可在8h内完全降解.采用海藻酸钠对菌体进行固定化后,Wust-C的降酚效率进一步得到提高.培养24 h后,固定化Wust-C对初始苯酚浓度为1 200 mg/L试样中的苯酚降解率达到100%,初始苯酚浓度为300 mg/L试样中的苯酚可在4h内完全降解.Wust-C的加入对混合菌群降解苯酚起到了促进作用.  相似文献   

8.
海藻酸钠-壳聚糖固定化漆酶的研究   总被引:5,自引:0,他引:5  
采用海藻酸钠包埋法和海藻酸钠-壳聚糖包埋-交联法固定化漆酶,探讨了固定化条件、固定化漆酶及游离酶的酶学性质,结果表明:包埋法和包埋-交联法固定化漆酶的最佳条件分别为海藻酸钠浓度3%、CaCl2浓度1.5%和海藻酸钠浓度2%、CaCl2浓度2%、壳聚糖浓度1.5%、戊二醛浓度1%.两种固定化漆酶的最适pH和最适温度相同,分别为5.0和30℃,游离酶pH为4.6,温度20℃.包埋法固定化漆酶、包埋一交联法固定化漆酶和游离酶的米氏常数分别为3.3,2.8,1.22mmol/L.  相似文献   

9.
以海藻酸钠和聚乙烯醇为混合载体,采取包埋法固定化苍白杆菌PW,降解培养基中的芘。在实验中分析了固定化载体浓度对固定化小球机械强度和传质系数的影响;绘制出固定化PW菌和游离菌降解芘的动力学曲线,比较了二者的差异;分析了pH值和温度对PW菌降解芘的影响。研究结果表明:随着海藻酸钠浓度的提高,固定化小球的传质性能变好,机械强度提高;随着聚乙烯醇的浓度的提高,固定化小球的传质性能变差,机械强度提高;在同样的条件下,固定化PW菌降解芘的效果要优于游离菌;固定化PW菌降解芘的最适pH为6.5~7.5,最适温度为30℃左右。  相似文献   

10.
以黑曲霉β-葡萄糖苷酶作为研究对像,采用交联-包埋的试验方法,以酶活力回收率作为评价的指标,选取海藻酸钠、壳聚糖、海藻酸钠-壳聚糖为载体,对β-葡萄糖苷酶固定化效果进行比较,结果显示海藻酸钠-壳聚糖固定化效果最好.再进行固定化条件单因素响应曲面试验,得到的最优条件为,海藻酸钠-壳聚糖的混合载体中海藻酸钠溶液的质量分数为1.91%、壳聚糖-醋酸溶液的质量分数为1.94%,温度为40.20℃,交联时间为0.98 h.此时酶活力为112 400 IU/m L,酶活力回收率为66.18%.经过三次回收试验,酶活力回收率分别为65.61%、64.48%、64.16%.  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.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
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   

17.
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   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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   

20.
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   

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