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1.
香根草和风车草人工湿地对猪场废水氮磷处理效果的研究   总被引:63,自引:5,他引:58  
分别以香根草 (Vetiveriazizanioides )和风车草 (Cyperusalternifolius)为植被 ,按 1.0m× 0 .5m×0 .8m建立人工湿地 ,通过四季测试研究其对猪场废水N、P的净化功能及其随季节、进水浓度及水力停留时间变化的规律 .结果表明 ,两湿地对NH3 N和S PO3 -4 去除率受污水停留时间和污水浓度影响较大 .香根草或风车草人工湿地在春季对NH3 N和S PO3 -4 有明显的去除效果 ;在秋季 ,则对去除废水TN均有效果 ,在去除TP上 ,香根草湿地效果明显 ,风车草湿地效果差 .秋春季人工湿地随水力停留时间 (t)延长 ,TP或S PO3 -4 (Y)的去除遵从指数方程Yt=Y0 ·e-kt规律 .冬季和夏季 ,进水浓度对湿地去除P影响较大 ;在相同停留时间内 ,冬夏季人工湿地随进水浓度变化 ,进出水S PO3 -4 遵从直线方程 y =a +bx规律  相似文献   

2.
 本文报道了凤眼莲对无锡电影胶片厂含银废水的净化生产性应用试验结果:(1)污水停留时间为49h时,氧化沟出水中的银净化率为98.0%到100%(未检出);(2)COD的去除率为54.58%;(3)混浊度的去除率为68.9%;(4)NH4+–N和PO43–的去除率分别为45.55%和34.3%。该法已被该厂采纳应用,并取代了原来的活性炭吸附和O3氧化三级处理,年节约运转费用12.5万元。  相似文献   

3.
目的和方法 :以SD大鼠递增负荷力竭性跑台运动为运动性疲劳模型 ,分别测定运动后即刻骨路肌线粒体 :①呼吸链复合体Ⅱ Ⅲ电子传递与质子泵出比值 (H /2e) ;②以琥珀酸 (S)为底物的呼吸控制 :态 3呼吸速率(R3 )、态 4呼及速率 (R4 )、呼吸控制比 (RCR)和磷 /氧比 (P/O) ;②H ATPase合成活力 ,探讨疲劳性运动中线粒体氧化磷酸化功能改变的机理。结果 :力竭性运动后以S为底物的线粒体R4升高 2 1.10 % (P <0 .0 5 ) ;呼吸链复合体Ⅱ Ⅲ的总、净H 2e分别降低 8.5 3和 19.5 1% (均P <0 .0 5 )。底物的RCR和P/O呈显著降低 (均P <0 .0 5 ) ,而底物的R3则有所增加 (P >0 .0 5 ) ,H ATPase合成活力降低 16.68% (P <0 .0 5 )。结论 :线粒体质子漏增加 ,呼吸链电子传递与质子泵出偶联程度下降 ,氧化磷酸化脱偶联导致无效氧耗增多 ,可能是运动性疲劳状态下线粒体氧利用率下降的重要机制。  相似文献   

4.
凤眼莲对含银废水中银的富集量及其应用研究   总被引:5,自引:0,他引:5  
1987—1989年进行了关于凤眼莲(Eichhornia crassipes)等水生植物对含银废水中银的富集量及其应用问题的研究。在国外,Wolverton测定了化学废水中凤眼莲根部对银的富集量为113ppm(占干物重),而本项研究在含银废水浓度为80—160ppb中生长的凤眼莲根部对银的富集量达12251ppm(占干物重),其富集系数F_x为102194,灰分含银量为4.125%,灰分富集系数F_x′为343750。并成功地从净化含银废水的凤眼莲植物残体(约6kg灰分)中提炼和回收白银105g。这不仅具有重要的科学意义,而且也为其它含贵稀金属的废水净化及回收有用金属提供了有益的经验。  相似文献   

5.
重组巴氏毕赤酵母恒化培养动力学及代谢迁移特性研究   总被引:5,自引:0,他引:5  
通过对甲醇营养型毕赤酵母基因工程菌以碳源甘油为限制性基质进行恒化培养动力学试验 ,结果认为 :(1 )细胞光密度与其干、湿重呈线性关系 ,当细胞光密度 (OD60 0 )为 1 0 0时细胞湿重 (WCW)为 1 2 8 3g L ,细胞干重 (WDW)则为 2 2 9g L ;(2 )基因工程菌P .pastoris的生长与限制性基质甘油残留浓度的关系符合Monod关系式 ,通过 1 μ对 1 S进行线性回归得 μmax=0 .366h- 1,Ks=0 .1 82 3g L ,经参数推导甘油最大菌体得率系数YG =0 .54g g ,菌体维持生长消耗底物系数m =0 .0 0 69g (g·h) ;氧最大菌体系数YX O2 =30 .96g moL ,菌体维持生长时消耗氧系数mO2 =0 .0 0 0 8mol (g·h) ,最适理论稀释速率Dm =0 .341h- 1;(3)从氨水的消耗速率和呼吸商 (RQ)的变化认为随着比生长速率 (μ)的增大 ,甘油代谢流从糖原异生和磷酸戊糖途径线性地向糖酵解和三羧酸循环途径进行代谢迁移 ,即糖酵解和三羧酸循环途径的代谢流量在线性地增大  相似文献   

6.
使用封闭式箱法,对大豆和玉米两种植物在苗期的N2O释放速率日变化及其同光强、气温的相关性进行了研究,同时对遮光、外加碳源和还原力对N2O释放速率的影响进行了分析.结果表明,两种植物苗期N2O释放速率在日间有两个释放高峰,分别出现在10:30和14:30.遮光处理实验结果证明,遮光后植物的N2O释放速率明显增加;相关性分析表明,苗期大豆在光强低于11345Lx时,N2O释放速率与光强呈正相关关系(R^2=0.7332),光强高于11345Lx时,呈负相关关系(R^2=0.7755),而苗期玉米在光强低于20000Lx时,N2O释放速率与光强呈正相关关系(R^2=0.8711),光强高于11345Lx时,呈负相关关系(R^2=0.8972).加入一定量的碳源(葡萄糖),可使遮光植物N2O的释放速率明显下降,由于同化力(NADH)的介入,在一定程度上影响了N2O的排放通量,同样使得N2O的释放量下降.  相似文献   

7.
目的 探索减毒甲型肝炎病毒( HAV) ( H2减毒株)在Hep G2 .2 .15细胞中对乙型肝炎病毒( HBV)表达HBs Ag和HBe Ag的影响。方法 在Hep G2 .2 .15细胞中,加入含3×10 - 2 ( 3×10 4 .5CCID50 / ml) ,3×10 - 3( 3×10 3.5CCID50 / ml)浓度的减毒HAV。按不同疫苗浓度,每4 d换液1次,留取第12和第16天的培养上清液;同时设立对照组。用微粒子酶免分析法检测培养上清液中的HBs Ag和HBe Ag含量。计算减毒HAV在不同浓度,以及不同作用时间长度的条件下,对Hep G2 .2 .15细胞表达HBs Ag和HBe Ag的影响。结果 3×10 - 2 Ampoule/ ml的减毒HAV作用Hep G2 .2 .5细胞12 d后,培养上清液的HBe Ag浓度为( 4 7.2 3±6 .18) S/ CO,低于对照组的( 10 1.15±15 .77) S/ CO,2组比较差异有非常显著性( P<0 .0 1) ;16 d后,上清液HBe Ag含量为( 4 0 .2 7±13.30 ) S/ CO,也显著低于对照组的( 6 5 .85±3.4 6 ) S/ CO( P<0 .0 5 ) ;HBs Ag含量为( 2 .6 8±0 .31) S/ N,低于对照组的( 5 .10±1.2 7)S/ N,差异有显著性( P<0 .0 5 )。而3×10 - 3Ampoule/ ml的减毒HAV作用Hep G2 .2 .15细胞12 d后,培养上清液的HBs Ag浓度与对照组比较有显著性下降( P<0 .0 5 )。结论 一定浓度的减毒HAV可能有直接抑制HBV表达HBs Ag,HBe Ag的作用  相似文献   

8.
凤眼莲净化燕山石油化工废水的研究Ⅰ.动态模拟试验   总被引:15,自引:2,他引:13  
两级串联凤眼莲塘净化燕山石化废水的动态模拟试验表睨:在温暖季节,凤眼莲塘对该废水有很强的净化能力,其净化效率明显高于普通氧化塘。总停留时间为8天的两级串联的凤眼莲塘可使出水达到规定要求。塘Ⅰ塘Ⅱ的去除率常数分别为0.376和0.151,表面净化率分别为9.51和2.38gCOD/m^2d,凤眼莲(湿重)增长量分别为226和210g/m^2d。当日平均气温在10—24℃的范围内,COD去除率(R)在日平均气温(T)的影响下以对数函数下降R87.70 JnT-200.15。根据试验,提出了动态凤眼莲塘净化燕山石化废水的定量计算方法和有关参数。  相似文献   

9.
淀银法在细胞学、组织学和神经解剖学的制片技术方面应用得非常广泛,而且方法也极多,但关于这一类方法的理论还缺乏系统的研究,即使是个别的研究在文献上也记载得不多。 1928年Lawrence S.Kubie等曾对硝酸二氨银[Ag(NH_3)_2NO_3]、氢氧化二氨银[Ag(NH_3)_2OH]和碳酸二氨银[Ag(NH_3)_2CO_3]溶液的制备方法和制备时所起的各  相似文献   

10.
硫酸盐还原菌净化含铬电镀废水的中试研究   总被引:17,自引:0,他引:17  
张介驰  庹莉 《生物技术》1997,7(1):32-34
本文研究了硫酸盐还原菌在还原剂的参与下净化含铬电镀废水中间试验的工艺条件,通过净化措施,使废水中Cr(6 )含量由30~40mg/L,下降为0.1mg/L以下,达到了废水排放标准。去除率为99.67~99.97%。分批净化电镀废水103t,试验证明废水净化工艺具有良好的稳定性。而且消除了二次污染。  相似文献   

11.
水生高等植物对废水中银的净化与富集特性研究   总被引:26,自引:0,他引:26  
戴全裕  戴文宁  高翔  卢红 《生态学报》1990,10(4):343-348
  相似文献   

12.
为解决中华鳖(Trionyx sinensis)养殖所造成的水环境污染问题,研究利用海藻酸钠、沸石对复合光合菌剂和枯草芽孢杆菌菌剂分别进行固定化,并研究了不同固定化微生物菌剂与蕹菜对中华鳖养殖污水的净化效果。结果表明:净化处理15d后,利用固定化微生物菌剂与蕹菜共同处理组对中华鳖养殖污水的净化处理效果最好,养殖污水的CODMn、NH 4+-N、NO3-N、NO 2-N、PO34的去除率分别为88.7%、87.3%、90.8%、98.3%、74.9%。蕹菜处理组对于NO3-N、NO 2-N、NH 4+-N的去除率显著高于固定化复合光合菌剂处理组和固定化枯草芽孢杆菌处理组。固定化复合光合菌剂处理组对于NO3-N、NO 2-N、NH 4+-N的去除率显著高于固定化枯草芽孢杆菌菌剂处理组,但固定化枯草芽孢杆菌处理组对于污水的CODMn的去除率最高,可达90.6%。  相似文献   

13.
浮床植物系统对富营养化水体中氮、磷净化特征的初步研究   总被引:75,自引:0,他引:75  
以浮床空心菜(Ipomoea aquatica)、水芹(Oenanthe javanica)和无植物系统为对象,研究了其在富营养化水体中对N、P的去除及其N2O的排放情况.结果表明,浮床植物系统对水体中N、P具有良好的净化效果,植物组织所累积的N、P量分别占各自系统去除量的40.32%~63.87%,说明植物的同化吸收作用是N、P去除的主要途径.换水周期内浮床植物系统中硝化反应进行充分,而反硝化反应相对缓慢,导致系统具有较高的NH4+-N去除率,而产生NO3--N累积.植物的存在降低了系统中N2O的排放通量.生长较好的空心菜系统在换水前后平均N2O排放量最低,为17.14μgN·m-2h-1,空白高达8.08μgN·m-2h-1,水芹为37.38μg N·m-2·h-1.  相似文献   

14.
Highly fluorinated tris(pyrazolyl)borate ligand [HB(3,5-(CF3)2Pz)3]- has been used in the isolation of air- and light-stable silver complex, [HB(3,5-(CF3)2Pz)3]Ag(OSMe2). It is a monomeric tetrahedral silver complex with an O-bonded dimethylsulfoxide ligand. The silver adduct [HB(3,5-(CF3)2Pz)3]Ag(OSMe2) and the related [HB(3,5-(CF3)2Pz)3] Ag(THF) (where OSMe2 = dimethyl sulfoxide; THF = tetrahydrofuran) show good antibacterial activity, and their antimicrobial efficacy against Staphylococcus aureus is greater than those of AgNO3 and silver sulfadiazine.  相似文献   

15.
Lin KS  Ding YS 《Chirality》2004,16(7):475-481
Reboxetine, 2-[alpha-(2-ethoxyphenoxy)benzyl]morpholine, is a highly selective norepinephrine transporter (NET) blocker that has been used for the treatment of depression. Its methyl analogue, 2-[alpha-(2-methoxyphenoxy)benzyl]morpholine (MRB), has been radiolabeled with C-11 for studies of the NET system with positron emission tomography (PET). The normethyl precursor, 2-[alpha-(2-hydroxyphenoxy)benzyl]morpholine (desethylreboxetine), was synthesized in 6% overall yield via a multi-step regio- and stereo-specific synthesis, starting from a mono-O-protected catechol. The resulting racemic mixture of desethylreboxetine was resolved by chiral HPLC to provide the (2S,3S) and (2R,3R) enantiomers in >98% enantiomeric excess. These enantiomers were then used as precursors for radiosynthesis to prepare enantiomerically pure individual 11C-labeled MRB enantiomers for comparative PET studies in baboons. Selective C-11 methylation at the phenolic oxygen with [11C]CH3I was achieved in the presence of excess base. After HPLC purification, racemic ((2S,3S)/(2R,3R)) or enantiomerically pure ((2S,3S) or (2R,3R)) [11C]MRB was obtained in 61-74% decay-corrected radiochemical yields from [11C]CH3I in a synthesis time of 40 min with a radiochemical purity of >96% and a specific activity of 1.7-2.3 Ci/micromol (63-85 GBq/micromol) corrected from the end of bombardment (EOB).  相似文献   

16.
Ion beams have been widely usedinthe semiconduc-tor industryand appliedfor surface modificationof materi-als since the1970s,while nobody had discussed howthese ion beams could be used in genetic modification inbiological science,evenfewpeople paid attentionto bio-logical effects induced byion beamandtheir possible usein genetics.In1986,Yu et al.have discovered the ge-netic effects in rice mediated by low energy ions[1—5].Since thenion beamradiation has been widely usedtoim-prove crops and the performance of...  相似文献   

17.
A Hoffmann  P Dimroth 《FEBS letters》1987,220(1):121-125
The steric course of the decarboxylation of (S)-methylmalonyl-CoA to propionyl-CoA, catalyzed by the biotin-dependent sodium pump methylmalonyl-CoA decarboxylase of Veillonella alcalescens was determined. The decarboxylation of (S)-methylmalonyl-CoA in 3H2O yielded (R)-[2-3H]propionyl-CoA; and the decarboxylation of (S)-[2-3H]methylmalonyl-CoA in H2O produced (S)-[2-3H]propionyl-CoA. The results demonstrate retention of configuration during the decarboxylation reaction. The substrate stereochemistry of methylmalonyl-CoA decarboxylase is thus the same as that of all other biotin-containing enzymes investigated.  相似文献   

18.
The lipid A disaccharide of the Escherichia coli envelope is synthesized from the two fatty acylated glucosamine derivatives UDP-N2,O3-bis[(R)-3-hydroxytetradecanoyl]-alpha-D- glucosamine (UDP-2,3-diacyl-GlcN) and N2,O3-bis[(R)-3-hydroxytetradecanoyl]-alpha-D-glucosamine 1-phosphate (2,3-diacyl-GlcN-1-P) [Ray, B. L., Painter, G., & Raetz, C. R. H. (1984) J. Biol. Chem. 259, 4852-4859]. We have previously shown that UDP-2,3-diacyl-GlcN is generated in extracts of E. coli by fatty acylation of UDP-GlcNAc, giving UDP-3-O-[(R)-3-hydroxymyristoyl]-GlcNAc as the first intermediate, which is rapidly converted to UDP-2,3-diacyl-GlcN [Anderson, M. S., Bulawa, C. E., & Raetz, C. R. H. (1985) J. Biol. Chem. 260, 15536-15541; Anderson, M. S., & Raetz, C. R. H. (1987) J. Biol. Chem. 262, 5159-5169]. We now demonstrate a novel enzyme in the cytoplasmic fraction of E. coli, capable of deacetylating UDP-3-O-[(R)-3-hydroxymyristoyl]-GlcNAc to form UDP-3-O-[(R)-3-hydroxymyristoyl]glucosamine. The covalent structure of the previously undescribed UDP-3-O-[(R)-3-hydroxymyristoyl] glucosamine intermediate was established by 1H NMR spectroscopy and fast atom bombardment mass spectrometry. This material can be made to accumulate in E. coli extracts upon incubation of UDP-3-O-[(R)-3- hydroxymyristoyl]-GlcNAc in the absence of the fatty acyl donor [(R)-3-hydroxymyristoyl]-acyl carrier protein. However, addition of the isolated deacetylation product [UDP-3-O-[(R)-3-hydroxymyristoyl] glucosamine] back to membrane-free extracts of E. coli in the presence of [(R)-3-hydroxymyristoyl]-acyl carrier protein results in rapid conversion of this compound into the more hydrophobic products UDP-2,3-diacyl-GlcN, 2,3-diacyl-GlcN-1-P, and O-[2-amino-2-deoxy-N2,O3- bis[(R)-3-hydroxytetradecanoyl]-beta-D-glucopyranosyl]-(1----6)-2-amino- 2-deoxy-N2,O3-bis[(R)-3-hydroxytetradecanoyl]-alpha-D- glucopyranose 1-phosphate (tetra-acyldisaccharide-1-P), demonstrating its competency as a precursor. In vitro incubations using [acetyl-3H]UDP-3-O-[(R)-3-hydroxymyristoyl]-GlcNAc confirmed release of the acetyl moiety in this system as acetate, not as some other acetyl derivative. The deacetylation reaction was inhibited by 1 mM N-ethylmaleimide, while the subsequent N-acylation reaction was not. Our observations provide strong evidence that UDP-3-O-[(R)-3-hydroxymyristoyl]glucosamine is a true intermediate in the biosynthesis of UDP-2,3-diacyl-GlcN and lipid A.  相似文献   

19.
牛心朴子须根的化学成分研究   总被引:6,自引:2,他引:4  
从采自宁夏的萝摩科鹅绒藤属植物牛心朴子 (CynanchumkomaroviiAl.Iljinski.)须根的乙醇提取物中分离鉴定了十个非C2 1 甾体类化合物 :β D 呋喃果糖基 (2→ 1) α D [6 O 芥子酰基 ] 吡喃葡萄糖甙 (1) ,β D (3 O 芥子酰基 ) 呋喃果糖基 (2→ 1) α D [6 O 芥子酰基 ] 吡喃葡萄糖甙 (2 ) ,[6 O β D 吡喃葡萄糖基 (1→ 6 ) β D 吡喃葡萄糖基 1,2 双氧 (4 羟基 3,5 二甲氧基肉桂酰 ) (3) ,7 脱甲氧基娃儿藤碱 (4) ,9 羟基 芳樟醇 3 O β D 吡喃木糖基 (1→ 6 ) β D 吡喃葡萄糖甙 (5 ) ,(2E ,6R) 2 ,6 二甲基 2 ,7 辛二烯 1,6 二醇 (6 ) ,[(+) 丁香素 ](7) ,4′ O demethylepiyangambin(8) ,4′ 羟基 2′ 甲氧基苯乙酮 (9) ,(2S ,3S ,4R ,12E) N [2′ (R) 羟基二十二碳烷基 ] 1,3,4 三羟基 2 酰胺 二十碳烷基 12 烯 (10 )。除化合物 4和 9外 ,其余化合物均为首次从该植物中分离得到。  相似文献   

20.
The use of affinity chromatography on wheat germ agglutinin columns to partially purify detergent extracts of muscarinic acetylcholine receptor from porcine atria is described. The procedure results in a 20-fold purification of the protein. The partially purified protein binds [3H]L-QNB (the L isomer of quinuclidinyl benzilate) with an observed association rate constant 2- to 3-fold lower than that found for the detergent extract; however, incubation with column fractions eluted prior to the receptor gives an association rate constant similar to that for detergent extracts. The component responsible for this effect is nondialyzable and protease sensitive, indicating that it may be a protein or high-molecular-weight peptide. Affinity labeling experiments with [3H]propylbenzilylcholine mustard [N. J. M. Birdsall, A. S. V. Burgen, and E. C. Hulme (1979) Brit. J. Pharmacol. 66, 337-342] show radioactivity incorporated mainly in a broad peak of apparent molecular weight 75,000 +/- 5000.  相似文献   

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